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Sample records for beetle dendroctonus valens

  1. Antennal Transcriptome Analysis of Odorant Reception Genes in the Red Turpentine Beetle (RTB), Dendroctonus valens

    PubMed Central

    Dong, Shuang-Lin; Zhang, Long-Wa

    2015-01-01

    Background The red turpentine beetle (RTB), Dendroctonus valens LeConte (Coleoptera: Curculionidae, Scolytinae), is a destructive invasive pest of conifers which has become the second most important forest pest nationwide in China. Dendroctonus valens is known to use host odors and aggregation pheromones, as well as non-host volatiles, in host location and mass-attack modulation, and thus antennal olfaction is of the utmost importance for the beetles’ survival and fitness. However, information on the genes underlying olfaction has been lacking in D. valens. Here, we report the antennal transcriptome of D. valens from next-generation sequencing, with the goal of identifying the olfaction gene repertoire that is involved in D. valens odor-processing. Results We obtained 51 million reads that were assembled into 61,889 genes, including 39,831 contigs and 22,058 unigenes. In total, we identified 68 novel putative odorant reception genes, including 21 transcripts encoding for putative odorant binding proteins (OBP), six chemosensory proteins (CSP), four sensory neuron membrane proteins (SNMP), 22 odorant receptors (OR), four gustatory receptors (GR), three ionotropic receptors (IR), and eight ionotropic glutamate receptors. We also identified 155 odorant/xenobiotic degradation enzymes from the antennal transcriptome, putatively identified to be involved in olfaction processes including cytochrome P450s, glutathione-S-transferases, and aldehyde dehydrogenase. Predicted protein sequences were compared with counterparts in Tribolium castaneum, Megacyllene caryae, Ips typographus, Dendroctonus ponderosae, and Agrilus planipennis. Conclusion The antennal transcriptome described here represents the first study of the repertoire of odor processing genes in D. valens. The genes reported here provide a significant addition to the pool of identified olfactory genes in Coleoptera, which might represent novel targets for insect management. The results from our study also will

  2. Gut-Associated Bacteria of Dendroctonus valens and their Involvement in Verbenone Production.

    PubMed

    Xu, Letian; Lou, Qiaozhe; Cheng, Chihang; Lu, Min; Sun, Jianghua

    2015-11-01

    Bark beetles are the most important mortality agent in coniferous forests, and pheromones play important roles in their management. Dendroctonus valens LeConte was introduced from North America to China and has killed millions of healthy pines there. Trapping with semiochemicals and pheromones was deployed in D. valens management in the last decade, but little is known about the ability of gut bacteria to produce the pheromone. In this study, we analyzed the volatiles in D. valens guts and frass after antibiotic treatment versus control. Then, we isolated and identified the bacteria in D. valens guts and frass, examined verbenone (a multifunctional pheromone of D. valens) production by 16 gut bacterial isolates from the precursor cis-verbenol at three concentrations, and further compared the cytotoxicities between the cis-verbenol and verbenone to the bacterial isolates. cis-Verbenol was not detected in the frass in the control group, but it was in the antibiotic treatment. The amount of verbenone was significantly suppressed in D. valens guts after antibiotic treatment versus control. Thirteen out of 16 gut bacterial isolates were capable of cis-verbenol to verbenone conversion, and cis-verbenol had stronger cytotoxicities than verbenone to all tested gut bacterial isolates. The bacterial species capable of verbenone production largely exists in D. valens guts and frass, suggesting that gut-associated bacteria may help the bark beetle produce the pheromone verbenone in guts and frass. The bacteria may benefit from the conversion due to the reduced cytotoxicity from the precursor to the beetle pheromone.

  3. Areas of potential suitability and survival of Dendroctonus valens in China under extreme climate warming scenario.

    PubMed

    He, S Y; Ge, X Z; Wang, T; Wen, J B; Zong, S X

    2015-08-01

    The areas in China with climates suitable for the potential distribution of the pest species red turpentine beetle (RTB) Dendroctonus valens LeConte (Coleoptera: Scolytidae) were predicted by CLIMEX based on historical climate data and future climate data with warming estimated. The model used a historical climate data set (1971-2000) and a simulated climate data set (2010-2039) provided by the Tyndall Centre for Climate Change (TYN SC 2.0). Based on the historical climate data, a wide area was available in China with a suitable climate for the beetle in which every province might contain suitable habitats for this pest, particularly all of the southern provinces. The northern limit of the distribution of the beetle was predicted to reach Yakeshi and Elunchun in Inner Mongolia, and the western boundary would reach to Keerkezi in Xinjiang Province. Based on a global-warming scenario, the area with a potential climate suited to RTB in the next 30 years (2010-2039) may extend further to the northeast. The northern limit of the distribution could reach most parts of south Heilongjiang Province, whereas the western limit would remain unchanged. Combined with the tendency for RTB to spread, the variation in suitable habitats within the scenario of extreme climate warming and the multiple geographical elements of China led us to assume that, within the next 30 years, RTB would spread towards the northeast, northwest, and central regions of China and could be a potentially serious problem for the forests of China.

  4. Yeast diversity associated with invasive Dendroctonus valens killing Pinus tabuliformis in China using culturing and molecular methods.

    PubMed

    Lou, Qiao-Zhe; Lu, Min; Sun, Jiang-Hua

    2014-08-01

    Bark beetle-associated yeasts are much less studied than filamentous fungi, yet they are also considered to play important roles in beetle nutrition, detoxification, and chemical communication. The red turpentine beetle, Dendroctonus valens, an invasive bark beetle introduced from North America, became one of the most destructive pests in China, having killed more than 10 million Pinus tabuliformis as well as other pine species. No investigation of yeasts associated with this bark beetle in its invaded ranges has been conducted so far. The aim of this study was to assess the diversity of yeast communities in different microhabitats and during different developmental stages of Den. valens in China using culturing and denaturing gradient gel electrophoresis (DGGE) approaches and to compare the yeast flora between China and the USA. The yeast identity was confirmed by sequencing the D1/D2 domain of LSU ribosomal DNA (rDNA). In total, 21 species (13 ascomycetes and eight basidiomycetes) were detected by culturing method, and 12 species (11 ascomycetes and one basidiomycetes) were detected by molecular methods from China. The most frequent five species in China were Candida piceae (Ogataea clade), Cyberlindnera americana, Candida oregonensis (Metschnikowia clade), Candida nitratophila (Ogataea clade) and an undescribed Saccharomycopsis sp., detected by both methods. Seven species were exclusively detected by DGGE. Ca. oregonensis (Metschnikowia clade) was the most frequently detected species by DGGE method. Eight species (all were ascomycetes) from the USA were isolated; seven of those were also found in China. We found significant differences in yeast total abundance as well as community composition between different developmental stages and significant differences between the surface and the gut. The frass yeast community was more similar to that of Den. valens surface or larvae than to the community of the gut or adults. Possible functions of the yeast associates are

  5. Diversity and expression of P450 genes from Dendroctonus valens LeConte (Curculionidae: Scolytinae) in response to different kairomones.

    PubMed

    López, María Fernanda; Cano-Ramírez, Claudia; Cesar-Ayala, Ana K; Ruiz, Enrico A; Zúñiga, Gerardo

    2013-05-01

    Bark beetles (Curculionidae: Scolytinae) are major cause of woody plants death in the world. They colonize the stem and other parts of trees recognizing host-produced specific compounds (kairomones) and insect pheromones. Bark beetle's antennae and alimentary canal participate in the host selection identifying chemical compounds produced by trees and insects, and also in the metabolism and detoxification of these compounds. The red turpentine beetle (RTB), Dendroctonus valens LeConte, is an unaggressive species that colonize > 40 pine species (Pinaceae) in North and Central America. Several studies suggest that bark beetle cytochrome P450 enzymes are involved in monoterpene oxidation. In this study we identified by means of PCR, cloning, sequencing, and bioinformatic analysis, eleven full-length genes: five CYP4, four CYP6, and two CYP9 in the antennae and gut region of RTB, after stimulation with vapors of monoterpenes: (±)-α-pinene, (R)-(+)-α-pinene, (S)-(-)-β-pinene, (S)-(-)-α-pinene and (+)-3-carene; pine trees volatiles used by RTB as kairomones. The recovered cDNA of these genes vary from 1.5 kb to 1.8 kb and the open frame encodes from 496 to 562 amino acid proteins. The bioinformatic analysis suggests that the majority of P450 proteins encoded by these genes are membrane anchored in the endoplasmic reticulum. RT-qPCR assays showed differential expression of all CYP genes between male and female. The gene expression was dependent of monoterpenes and exposure time, with some of them sex, antennae and gut region specific. Significant differences among monoterpenes, gut region, antennae and exposure time were found. Our results suggest that some of these genes may be involved in the detoxification process of these compounds during tree colonization. PMID:23454142

  6. Bacterial and fungal symbionts of parasitic Dendroctonus bark beetles.

    PubMed

    Dohet, Loïc; Grégoire, Jean-Claude; Berasategui, Aileen; Kaltenpoth, Martin; Biedermann, Peter H W

    2016-09-01

    Bark beetles (Curculionidae: Scolytinae) are one of the most species-rich herbivorous insect groups with many shifts in ecology and host-plant use, which may be mediated by their bacterial and fungal symbionts. While symbionts are well studied in economically important, tree-killing species, little is known about parasitic species whose broods develop in living trees. Here, using culture-dependent and independent methods, we provide a comprehensive overview of the associated bacteria, yeasts and filamentous fungi of the parasitic Dendroctonus micans, D. punctatus and D. valens, and compare them to those of other tree-inhabiting insects. Despite inhabiting different geographical regions and/or host trees, the three species showed similar microbial communities. Enterobacteria were the most prevalent bacteria, in particular Rahnella, Pantoea and Ewingella, in addition to Streptomyces Likewise, the yeasts Candida/Cyberlindnera were the most prominent fungi. All these microorganisms are widespread among tree-inhabiting insects with various ecologies, but their high prevalence overall might indicate a beneficial role such as detoxification of tree defenses, diet supplementation or protection against pathogens. As such, our results enable comparisons of symbiont communities of parasitic bark beetles with those of other beetles, and will contribute to our understanding of how microbial symbioses facilitate dietary shifts in insects. PMID:27387908

  7. Maintenance of midgut epithelial cells from Dendroctonus valens (Coleoptera: Scolytidae) in vitro.

    PubMed

    Sánchez, L; Andrade, J L; Cisneros, R; Zúñiga, G

    2004-01-01

    This article describes the culture of epithelial cells from anterior and posterior midgut regions of adult Dendroctonus valens. Culture conditions were established, and cell adherence was improved by means of a new technique that allowed the cells to grow between two glass coverslips. Cytoplasmic projections occur as anterior midgut cells grow to confluence; these projections were not observed in cells of the posterior midgut. The optimal culture medium for the maintenance of these epithelial cells was Roswell Park Memorial Institute 1640 medium at 25 degrees C. Cells in Grace's medium died in 24 h. Cultures did not require CO(2) atmosphere, but culture development was favored by the microaerophilic environment and the dark conditions in which the cells were grown, between the coverslips.

  8. Modeling cold tolerance in the mountain pine beetle, Dendroctonus ponderosae.

    PubMed

    Régnière, Jacques; Bentz, Barbara

    2007-06-01

    Cold-induced mortality is a key factor driving mountain pine beetle, Dendroctonus ponderosae, population dynamics. In this species, the supercooling point (SCP) is representative of mortality induced by acute cold exposure. Mountain pine beetle SCP and associated cold-induced mortality fluctuate throughout a generation, with the highest SCPs prior to and following winter. Using observed SCPs of field-collected D. ponderosae larvae throughout the developmental season and associated phloem temperatures, we developed a mechanistic model that describes the SCP distribution of a population as a function of daily changes in the temperature-dependent processes leading to gain and loss of cold tolerance. It is based on the changing proportion of individuals in three states: (1) a non cold-hardened, feeding state, (2) an intermediate state in which insects have ceased feeding, voided their gut content and eliminated as many ice-nucleating agents as possible from the body, and (3) a fully cold-hardened state where insects have accumulated a maximum concentration of cryoprotectants (e.g. glycerol). Shifts in the proportion of individuals in each state occur in response to the driving variables influencing the opposite rates of gain and loss of cold hardening. The level of cold-induced mortality predicted by the model and its relation to extreme winter temperature is in good agreement with a range of field and laboratory observations. Our model predicts that cold tolerance of D. ponderosae varies within a season, among seasons, and among geographic locations depending on local climate. This variability is an emergent property of the model, and has important implications for understanding the insect's response to seasonal fluctuations in temperature, as well as population response to climate change. Because cold-induced mortality is but one of several major influences of climate on D. ponderosae population dynamics, we suggest that this model be integrated with others

  9. Dispersal of the spruce beetle, `dendroctonus rufipennis`, and the engraver beetle, `ips perturbatus`, in Alaska. Forest Service research paper

    SciTech Connect

    Werner, R.A.; Holsten, E.H.

    1997-09-01

    Mark-release-recapture experiments were performed with spruce beetles (Dendroctonus rufipennis (Kirby)) and Ips engraver beetles (Ips perturbatus (Eichhoff)) to determine distance and direction of dispersal. The recapture rate of beetles marked with fluorescent powder was extremely low. Most I. perturbatus beetles dispersed up to 30 m from their overwintering sites compared to most D. rufipennis, which dispersed from 90 to 300 m. Ips perturbatus beetles were caught up to 90 m and D. rufipennis up to 600 m from the point of release.

  10. Surveying the endomicrobiome and ectomicrobiome of bark beetles: The case of Dendroctonus simplex.

    PubMed

    Durand, Audrey-Anne; Bergeron, Amélie; Constant, Philippe; Buffet, Jean-Philippe; Déziel, Eric; Guertin, Claude

    2015-11-26

    Many bark beetles belonging to the Dendroctonus genus carry bacterial and fungal microbiota, forming a symbiotic complex that helps the insect to colonize the subcortical environment of the host tree. However, the biodiversity of those bacteria at the surface of the cuticle or inside the body parts of bark beetles is not well established. The aim of this study was to characterize the bacterial microbiome associated with the eastern larch beetle, Dendroctonus simplex, using bacterial 16S rRNA gene pyrosequencing. The ecto- and endomicrobiome and the subcortical galleries were investigated. Several bacterial genera were identified, among which Pseudomonas, Serratia and Yersinia are associated with the surface of the beetle cuticle, and genera belonging to Enterobacteriaceae and Gammaproteobacteria with the interior of the insect body. The index of dissimilarity indicates that the bacterial microbiome associated with each environment constitutes exclusive groups. These results suggest the presence of distinct bacterial microbiota on the surface of the cuticle and the interior of D. simplex body. Additionally, the bacterial diversity identified in the galleries is substantially different from the ectomicrobiome, which could indicate a selection by the insect. This study reports for the first time the identification of the eastern larch beetle microbiome.

  11. Surveying the endomicrobiome and ectomicrobiome of bark beetles: The case of Dendroctonus simplex

    PubMed Central

    Durand, Audrey-Anne; Bergeron, Amélie; Constant, Philippe; Buffet, Jean-Philippe; Déziel, Eric; Guertin, Claude

    2015-01-01

    Many bark beetles belonging to the Dendroctonus genus carry bacterial and fungal microbiota, forming a symbiotic complex that helps the insect to colonize the subcortical environment of the host tree. However, the biodiversity of those bacteria at the surface of the cuticle or inside the body parts of bark beetles is not well established. The aim of this study was to characterize the bacterial microbiome associated with the eastern larch beetle, Dendroctonus simplex, using bacterial 16S rRNA gene pyrosequencing. The ecto- and endomicrobiome and the subcortical galleries were investigated. Several bacterial genera were identified, among which Pseudomonas, Serratia and Yersinia are associated with the surface of the beetle cuticle, and genera belonging to Enterobacteriaceae and Gammaproteobacteria with the interior of the insect body. The index of dissimilarity indicates that the bacterial microbiome associated with each environment constitutes exclusive groups. These results suggest the presence of distinct bacterial microbiota on the surface of the cuticle and the interior of D. simplex body. Additionally, the bacterial diversity identified in the galleries is substantially different from the ectomicrobiome, which could indicate a selection by the insect. This study reports for the first time the identification of the eastern larch beetle microbiome. PMID:26608752

  12. The response of mountain pine beetle (Dendroctonus ponderosae) to lodgepole pine trees baited with verbenone and exo-brevicomin.

    PubMed

    Shore, T L; Safranyak, L; Lindgren, B S

    1992-04-01

    exo-brevicomin, a multifunctional pheromone of the mountain pine beetle,Dendroctonus ponderosae, was tested at release rates of 0.5 and 2.5 mg/day alone and in combination with the antiaggregation pheromone verbenone against unbaited controls. Significantly more lodgepole pinePinus contorta var.latifolia trees were attacked, and at higher densities, with both release rates ofexo-brevicomin than with all other treatments. Verbenone significantly reduced the response of mountain pine beetles toexo-brevicomin. Verbenone alone did not reduce the number of trees attacked by mountain pine beetle or the attack density when compared to the unbaited controls.

  13. exo-Brevicomin biosynthesis in the fat body of the mountain pine beetle, Dendroctonus ponderosae.

    PubMed

    Song, Minmin; Gorzalski, Andrew; Nguyen, Trang T; Liu, Xibei; Jeffrey, Christopher; Blomquist, Gary J; Tittiger, Claus

    2014-02-01

    exo-Brevicomin (exo-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octane) is an important semiochemical for a number of beetle species, including the highly destructive mountain pine beetle, Dendroctonus ponderosae. It also has been found in other insects and even in the African elephant. Despite its significance, little is known about its biosynthesis. In order to fill this gap and to identify new molecular targets for potential pest management methods, we performed gas chromatography-mass spectrometry analyses of cell cultures and in vitro assays of various D. ponderosae tissues with exo-brevicomin intermediates, analogs, and inhibitors. We confirmed that exo-brevicomin was synthesized by "unfed" males after emerging from the brood tree. Furthermore, in contrast to the paradigm established for biosynthesis of monoterpenoid pheromone components in bark beetles, exo-brevicomin was produced in the fat body, and not in the anterior midgut. The first committed step involves decarboxylation or decarbonylation of ω-3-decenoic acid, which is derived from a longer-chain precursor via β-oxidation, to (Z)-6-nonen-2-ol. This secondary alcohol is converted to the known precursor, (Z)-6-nonen-2-one, and further epoxidized by a cytochrome P450 to 6,7-epoxynonan-2-one. The keto-epoxide is stable at physiological pH, suggesting that its final cyclization to form exo-brevicomin is enzyme-catalyzed. exo-Brevicomin production is unusual in that tissue not derived from ectoderm apparently is involved. PMID:24532213

  14. exo-Brevicomin biosynthesis in the fat body of the mountain pine beetle, Dendroctonus ponderosae.

    PubMed

    Song, Minmin; Gorzalski, Andrew; Nguyen, Trang T; Liu, Xibei; Jeffrey, Christopher; Blomquist, Gary J; Tittiger, Claus

    2014-02-01

    exo-Brevicomin (exo-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octane) is an important semiochemical for a number of beetle species, including the highly destructive mountain pine beetle, Dendroctonus ponderosae. It also has been found in other insects and even in the African elephant. Despite its significance, little is known about its biosynthesis. In order to fill this gap and to identify new molecular targets for potential pest management methods, we performed gas chromatography-mass spectrometry analyses of cell cultures and in vitro assays of various D. ponderosae tissues with exo-brevicomin intermediates, analogs, and inhibitors. We confirmed that exo-brevicomin was synthesized by "unfed" males after emerging from the brood tree. Furthermore, in contrast to the paradigm established for biosynthesis of monoterpenoid pheromone components in bark beetles, exo-brevicomin was produced in the fat body, and not in the anterior midgut. The first committed step involves decarboxylation or decarbonylation of ω-3-decenoic acid, which is derived from a longer-chain precursor via β-oxidation, to (Z)-6-nonen-2-ol. This secondary alcohol is converted to the known precursor, (Z)-6-nonen-2-one, and further epoxidized by a cytochrome P450 to 6,7-epoxynonan-2-one. The keto-epoxide is stable at physiological pH, suggesting that its final cyclization to form exo-brevicomin is enzyme-catalyzed. exo-Brevicomin production is unusual in that tissue not derived from ectoderm apparently is involved.

  15. Metabolism and cold tolerance of overwintering adult mountain pine beetles (Dendroctonus ponderosae): evidence of facultative diapause?

    PubMed

    Lester, Jack D; Irwin, Jason T

    2012-06-01

    We sought evidence for a distinct diapause in adult overwintering mountain pine beetles (Dendroctonus ponderosae Hopkins) by measuring metabolic rate and supercooling ability of field collected beetles throughout the year. Metabolic rates measured at 0, 5, and 10°C declined significantly from October through November, then rose slowly, reaching levels as high as those recorded in October by late May. From December to February metabolic rates were not correlated with minimum weekly phloem temperatures (R(2)=0.0%, P=0.592), but were correlated with phloem temperatures as winter advanced to spring (R(2)=44.8%, P=0.010), a pattern consistent with progression through the maintenance and termination phases of diapause. Supercooling points were also significantly lower in winter compared to fall and spring (F((8,143))=32.6, P<0.001) and were closely correlated with metabolic rates (R(2)>79% for all three temperatures). Dry mass declined linearly with winter progression (F((8,150))=8.34, P<0.001), explained by catabolism of metabolic reserves, with a concomitant accumulation of metabolic water (F((8,147))=35.24, P<0.001). The strong mid-winter metabolic suppression correlated with improved supercooling ability, coupled with their lack of response to variation in environmental temperature, are evidence of possible diapause in adult overwintering mountain pine beetles.

  16. Monoterpene metabolism in female mountain pine beetles,Dendroctonus ponderosae Hopkins, attacking ponderosa pine.

    PubMed

    Pierce, H D; Conn, J E; Oehlschlager, A C; Borden, J H

    1987-06-01

    Abdominal volatiles of female mountain pine beetles,Dendroctonus ponderosae Hopkins, fed in ponderosa pine,Pinus ponderosa Dougl. ex Laws, and in lodgepole pine,P. contorta var.latifolia Engelmann, were analyzed by gas chromatography and coupled gas chromatography-mass spectrometry and were found to comprise host oleoresin components and beetle-produced alliylic alcohols, aldehydes, and ketones derived from host monoterpenes. Neitherexo- andendo-brevicomin nor frontalin were detected. Three metabolic pathways are proposed to account for the distribution of beetle-produced monoterpene alcohols. The first pathway involves hydroxylation of monoterpene substrates on allylic methyl groups which areE to a methylene or vinyl group. This oxidation pathway is indiscriminate with respect to substrate and probably functions to detoxify monoterpenes. A second pathway, which hydroxylates theendo-cyclic methyleneE to a vinyl methyl group of bicyclic monoterpenes to give almost exclusively thetrans alcohol, is hypothesized to be involved in pheromone production. A third detoxification pathway involves anti-Markovnikov addition of water to theexo-cyclic double bond of β-phellandrene to give predominantlytrans-2-p-menthen-7-ol.

  17. Draft genome of the mountain pine beetle, Dendroctonus ponderosae Hopkins, a major forest pest

    PubMed Central

    2013-01-01

    Background The mountain pine beetle, Dendroctonus ponderosae Hopkins, is the most serious insect pest of western North American pine forests. A recent outbreak destroyed more than 15 million hectares of pine forests, with major environmental effects on forest health, and economic effects on the forest industry. The outbreak has in part been driven by climate change, and will contribute to increased carbon emissions through decaying forests. Results We developed a genome sequence resource for the mountain pine beetle to better understand the unique aspects of this insect's biology. A draft de novo genome sequence was assembled from paired-end, short-read sequences from an individual field-collected male pupa, and scaffolded using mate-paired, short-read genomic sequences from pooled field-collected pupae, paired-end short-insert whole-transcriptome shotgun sequencing reads of mRNA from adult beetle tissues, and paired-end Sanger EST sequences from various life stages. We describe the cytochrome P450, glutathione S-transferase, and plant cell wall-degrading enzyme gene families important to the survival of the mountain pine beetle in its harsh and nutrient-poor host environment, and examine genome-wide single-nucleotide polymorphism variation. A horizontally transferred bacterial sucrose-6-phosphate hydrolase was evident in the genome, and its tissue-specific transcription suggests a functional role for this beetle. Conclusions Despite Coleoptera being the largest insect order with over 400,000 described species, including many agricultural and forest pest species, this is only the second genome sequence reported in Coleoptera, and will provide an important resource for the Curculionoidea and other insects. PMID:23537049

  18. Leptographium longiclavatum sp. nov., a new species associated with the mountain pine beetle, Dendroctonus ponderosae.

    PubMed

    Lee, Sangwon; Kim, Jae-Jin; Breuil, Colette

    2005-10-01

    The mountain pine beetle, Dendroctonus ponderosae, and its fungal associates are devastating the lodgepole pine forests in British Columbia, Canada. During our fungal survey, an unknown Leptographium species has been consistently isolated from both D. ponderosae and infested lodgepole pine (Pinus contorta var. latifolia). This Leptographium species has similar morphology with the Leptographium anamorph of Ophiostoma clavigerum whose association with the D. ponderosae is well known. However, thorough morphological comparisons showed that this fungus is distinct from all the other Leptographium species described in the literature, and especially from O. clavigerum. Comparison of DNA sequences of multiple loci and the profiles by the PCR-RFLP marker also confirmed that this Leptographium species represents an undescribed taxon. Based on its distinct morphological, physiological characteristics and phylogenetic position, we describe it as L. longiclavatum sp. nov.

  19. Southern pine beetle, Dendroctonus frontalis, antennal and behavioral responses to nonhost leaf and bark volatiles.

    PubMed

    Shepherd, William P; Sullivan, Brian T

    2013-04-01

    A growing body of evidence suggests that bark beetles detect and avoid release points of volatile compounds associated with nonhost species, and thus such nonhost volatiles may have potential utility in the management of bark beetles. We used a coupled gas chromatograph-electroantennographic detector (GC-EAD) to assay the olfactory sensitivity of the southern pine beetle, Dendroctonus frontalis Zimmermann, to volatiles from leaves and bark of eight species of nonhost angiosperm trees that are common in the range of D. frontalis. Tree species sampled were red maple (Acer rubrum L.), mockernut hickory [Carya alba (L.) Nutt. ex Ell.], sweetgum (Liquidambar styraciflua L.), black tupelo (Nyssa sylvatica Marsh.), black cherry (Prunus serotina Ehrh.), southern red oak (Quercus falcata Michx.), blackjack oak [Quercus marilandica (L.) Muenchh.], and water oak (Quercus nigra L.). Beetle antennae responded to a total of 28 identifiable compounds in these samples. The relative olfactory responsiveness to 14 of these, as well as to nonanoic acid and four additional volatiles reported to be associated with nonhost angiosperms, was assessed in GC-EAD analyses of synthetic dilutions spanning six orders of magnitude. The largest response voltage amplitudes were obtained with trans-conophthorin, nonanoic acid, terpinen-4-ol, phenylethyl alcohol, and eucalyptol, whereas the lowest response thresholds were to nonanoic acid, nonanal, linalool, (E)-2-hexen-1-ol, and phenylethyl alcohol. Funnel traps baited with various combinations of eleven antennally-active angiosperm volatiles along with a standard attractant captured significantly fewer male and female D. frontalis than traps baited with the standard attractant alone. Our data suggest that a diversity of semiochemicals may be involved in host species discrimination by D. frontalis, and several may have utility in their management. PMID:23460417

  20. exo-Brevicomin biosynthetic pathway enzymes from the Mountain Pine Beetle, Dendroctonus ponderosae.

    PubMed

    Song, Minmin; Delaplain, Patrick; Nguyen, Trang T; Liu, Xibei; Wickenberg, Leah; Jeffrey, Christopher; Blomquist, Gary J; Tittiger, Claus

    2014-10-01

    exoBrevicomin (exo-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octane) is an important semiochemical for a number of beetle species, including the highly destructive Mountain Pine Beetle (Dendroctonus ponderosae). It is also found in other insects and the African elephant. Despite its significance, very little is known about its biosynthesis. A recent microarray analysis implicated a small cluster of three D. ponderosae genes in exo-brevicomin biosynthesis, two of which had identifiable open reading frames (Aw et al., 2010; BMC Genomics 11:215). Here we report further expression profiling of two genes in that cluster and functional analysis of their recombinantly-produced enzymes. One encodes a short-chain dehydrogenase that used NAD(P)(+) as a co-factor to catalyze the oxidation of (Z)-6-nonen-2-ol to (Z)-6-nonen-2-one. We therefore named the enzyme (Z)-6-nonen-2-ol dehydrogenase (ZnoDH). The other encodes the cytochrome P450, CYP6CR1, which epoxidized (Z)-6-nonen-2-one to 6,7-epoxynonan-2-one with very high specificity and substrate selectivity. Both the substrates and products of the two enzymes are intermediates in the exo-brevicomin biosynthetic pathway. Thus, ZnoDH and CYP6CR1 are enzymes that apparently catalyze the antepenultimate and penultimate steps in the exo-brevicomin biosynthetic pathway, respectively. PMID:25138711

  1. exo-Brevicomin biosynthetic pathway enzymes from the Mountain Pine Beetle, Dendroctonus ponderosae.

    PubMed

    Song, Minmin; Delaplain, Patrick; Nguyen, Trang T; Liu, Xibei; Wickenberg, Leah; Jeffrey, Christopher; Blomquist, Gary J; Tittiger, Claus

    2014-10-01

    exoBrevicomin (exo-7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octane) is an important semiochemical for a number of beetle species, including the highly destructive Mountain Pine Beetle (Dendroctonus ponderosae). It is also found in other insects and the African elephant. Despite its significance, very little is known about its biosynthesis. A recent microarray analysis implicated a small cluster of three D. ponderosae genes in exo-brevicomin biosynthesis, two of which had identifiable open reading frames (Aw et al., 2010; BMC Genomics 11:215). Here we report further expression profiling of two genes in that cluster and functional analysis of their recombinantly-produced enzymes. One encodes a short-chain dehydrogenase that used NAD(P)(+) as a co-factor to catalyze the oxidation of (Z)-6-nonen-2-ol to (Z)-6-nonen-2-one. We therefore named the enzyme (Z)-6-nonen-2-ol dehydrogenase (ZnoDH). The other encodes the cytochrome P450, CYP6CR1, which epoxidized (Z)-6-nonen-2-one to 6,7-epoxynonan-2-one with very high specificity and substrate selectivity. Both the substrates and products of the two enzymes are intermediates in the exo-brevicomin biosynthetic pathway. Thus, ZnoDH and CYP6CR1 are enzymes that apparently catalyze the antepenultimate and penultimate steps in the exo-brevicomin biosynthetic pathway, respectively.

  2. Direction of interaction between mountain pine beetle (Dendroctonus ponderosae) and resource-sharing wood-boring beetles depends on plant parasite infection.

    PubMed

    Klutsch, Jennifer G; Najar, Ahmed; Cale, Jonathan A; Erbilgin, Nadir

    2016-09-01

    Plant pathogens can have cascading consequences on insect herbivores, though whether they alter competition among resource-sharing insect herbivores is unknown. We experimentally tested whether the infection of a plant pathogen, the parasitic plant dwarf mistletoe (Arceuthobium americanum), on jack pine (Pinus banksiana) altered the competitive interactions among two groups of beetles sharing the same resources: wood-boring beetles (Coleoptera: Cerambycidae) and the invasive mountain pine beetle (Dendroctonus ponderosae) (Coleoptera: Curculionidae). We were particularly interested in identifying potential mechanisms governing the direction of interactions (from competition to facilitation) between the two beetle groups. At the lowest and highest disease severity, wood-boring beetles increased their consumption rate relative to feeding levels at moderate severity. The performance (brood production and feeding) of mountain pine beetle was negatively associated with wood-boring beetle feeding and disease severity when they were reared separately. However, when both wood-boring beetles and high severity of plant pathogen infection occurred together, mountain pine beetle escaped from competition and improved its performance (increased brood production and feeding). Species-specific responses to changes in tree defense compounds and quality of resources (available phloem) were likely mechanisms driving this change of interactions between the two beetle groups. This is the first study demonstrating that a parasitic plant can be an important force in mediating competition among resource-sharing subcortical insect herbivores. PMID:26820567

  3. Direction of interaction between mountain pine beetle (Dendroctonus ponderosae) and resource-sharing wood-boring beetles depends on plant parasite infection.

    PubMed

    Klutsch, Jennifer G; Najar, Ahmed; Cale, Jonathan A; Erbilgin, Nadir

    2016-09-01

    Plant pathogens can have cascading consequences on insect herbivores, though whether they alter competition among resource-sharing insect herbivores is unknown. We experimentally tested whether the infection of a plant pathogen, the parasitic plant dwarf mistletoe (Arceuthobium americanum), on jack pine (Pinus banksiana) altered the competitive interactions among two groups of beetles sharing the same resources: wood-boring beetles (Coleoptera: Cerambycidae) and the invasive mountain pine beetle (Dendroctonus ponderosae) (Coleoptera: Curculionidae). We were particularly interested in identifying potential mechanisms governing the direction of interactions (from competition to facilitation) between the two beetle groups. At the lowest and highest disease severity, wood-boring beetles increased their consumption rate relative to feeding levels at moderate severity. The performance (brood production and feeding) of mountain pine beetle was negatively associated with wood-boring beetle feeding and disease severity when they were reared separately. However, when both wood-boring beetles and high severity of plant pathogen infection occurred together, mountain pine beetle escaped from competition and improved its performance (increased brood production and feeding). Species-specific responses to changes in tree defense compounds and quality of resources (available phloem) were likely mechanisms driving this change of interactions between the two beetle groups. This is the first study demonstrating that a parasitic plant can be an important force in mediating competition among resource-sharing subcortical insect herbivores.

  4. How the mountain pine beetle (Dendroctonus ponderosae) breached the Canadian Rocky Mountains.

    PubMed

    Janes, Jasmine K; Li, Yisu; Keeling, Christopher I; Yuen, Macaire M S; Boone, Celia K; Cooke, Janice E K; Bohlmann, Joerg; Huber, Dezene P W; Murray, Brent W; Coltman, David W; Sperling, Felix A H

    2014-07-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins), a major pine forest pest native to western North America, has extended its range north and eastward during an ongoing outbreak. Determining how the MPB has expanded its range to breach putative barriers, whether physical (nonforested prairie and high elevation of the Rocky Mountains) or climatic (extreme continental climate where temperatures can be below -40 °C), may contribute to our general understanding of range changes as well as management of the current epidemic. Here, we use a panel of 1,536 single nucleotide polymorphisms (SNPs) to assess population genetic structure, connectivity, and signals of selection within this MPB range expansion. Biallelic SNPs in MPB from southwestern Canada revealed higher genetic differentiation and lower genetic connectivity than in the northern part of its range. A total of 208 unique SNPs were identified using different outlier detection tests, of which 32 returned annotations for products with putative functions in cholesterol synthesis, actin filament contraction, and membrane transport. We suggest that MPB has been able to spread beyond its previous range by adjusting its cellular and metabolic functions, with genome scale differentiation enabling populations to better withstand cooler climates and facilitate longer dispersal distances. Our study is the first to assess landscape-wide selective adaptation in an insect. We have shown that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this forest pest species. PMID:24803641

  5. How the Mountain Pine Beetle (Dendroctonus ponderosae) Breached the Canadian Rocky Mountains

    PubMed Central

    Janes, Jasmine K.; Li, Yisu; Keeling, Christopher I.; Yuen, Macaire M.S.; Boone, Celia K.; Cooke, Janice E.K.; Bohlmann, Joerg; Huber, Dezene P.W.; Murray, Brent W.; Coltman, David W.; Sperling, Felix A.H.

    2014-01-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins), a major pine forest pest native to western North America, has extended its range north and eastward during an ongoing outbreak. Determining how the MPB has expanded its range to breach putative barriers, whether physical (nonforested prairie and high elevation of the Rocky Mountains) or climatic (extreme continental climate where temperatures can be below −40 °C), may contribute to our general understanding of range changes as well as management of the current epidemic. Here, we use a panel of 1,536 single nucleotide polymorphisms (SNPs) to assess population genetic structure, connectivity, and signals of selection within this MPB range expansion. Biallelic SNPs in MPB from southwestern Canada revealed higher genetic differentiation and lower genetic connectivity than in the northern part of its range. A total of 208 unique SNPs were identified using different outlier detection tests, of which 32 returned annotations for products with putative functions in cholesterol synthesis, actin filament contraction, and membrane transport. We suggest that MPB has been able to spread beyond its previous range by adjusting its cellular and metabolic functions, with genome scale differentiation enabling populations to better withstand cooler climates and facilitate longer dispersal distances. Our study is the first to assess landscape-wide selective adaptation in an insect. We have shown that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this forest pest species. PMID:24803641

  6. Differential impacts of the southern pine beetle, Dendroctonus frontalis, on Pinus palustris and Pinus taeda

    USGS Publications Warehouse

    Friedenberg, N.A.; Whited, B.M.; Slone, D.H.; Martinson, S.J.; Ayres, M.P.

    2007-01-01

    Patterns of host use by herbivore pests can have serious consequences for natural and managed ecosystems but are often poorly understood. Here, we provide the first quantification of large differential impacts of the southern pine beetle, Dendroctonus frontalis Zimmermann, on loblolly pine, Pinus taeda L., and longleaf pine, Pinus palustris P. Mill., and evaluate putative mechanisms for the disparity. Spatially extensive survey data from recent epidemics indicate that, per square kilometre, stands of loblolly versus longleaf pine in four forests (380-1273 km2) sustained 3-18 times more local infestations and 3-116 times more tree mortality. Differences were not attributable to size or age structure of pine stands. Using pheromone-baited traps, we found no differences in the abundance of dispersing D. frontalis or its predator Thanasimus dubius Fabricius between loblolly and longleaf stands. Trapping triggered numerous attacks on trees, but the pine species did not differ in the probability of attack initiation or in the surface area of bark attacked by growing aggregations. We found no evidence for postaggregation mechanisms of discrimination or differential success on the two hosts, suggesting that early colonizers discriminate between host species before a pheromone plume is present. ?? 2007 NRC.

  7. Landscape-scale genetic variation in a forest outbreak species, the mountain pine beetle (Dendroctonus ponderosae).

    PubMed

    Mock, K E; Bentz, B J; O'neill, E M; Chong, J P; Orwin, J; Pfrender, M E

    2007-02-01

    The mountain pine beetle Dendroctonus ponderosae is a native species currently experiencing large-scale outbreaks in western North American pine forests. We sought to describe the pattern of genetic variation across the range of this species, to determine whether there were detectable genetic differences between D. ponderosae occupying different host trees in common localities, and to determine whether there was molecular evidence for a past demographic expansion. Using a combination of amplified fragment length polymorphism (AFLP) and mitochondrial sequencing analyses, we found evidence of genetic structuring among populations that followed a broad isolation-by-distance pattern. Our results suggest that the geographical pattern of gene flow follows the core distribution of the principal D. ponderosae host species, around rather than across the Great Basin and Mojave Deserts. Patterns of haplotype diversity and divergence were consistent with a range-wide population expansion. This signal was particularly pronounced in the northern part of the species' range, where outbreak activity is currently increasing. Using AFLP markers, we were unable to detect significant differences among groups of insects sampled from different host trees in common locations. Incidentally, we found that a large proportion of the polymorphic AFLP markers were gender-specific, occurring only in males. While we did not include these markers in our analyses, this finding warrants further investigation.

  8. How the mountain pine beetle (Dendroctonus ponderosae) breached the Canadian Rocky Mountains.

    PubMed

    Janes, Jasmine K; Li, Yisu; Keeling, Christopher I; Yuen, Macaire M S; Boone, Celia K; Cooke, Janice E K; Bohlmann, Joerg; Huber, Dezene P W; Murray, Brent W; Coltman, David W; Sperling, Felix A H

    2014-07-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae Hopkins), a major pine forest pest native to western North America, has extended its range north and eastward during an ongoing outbreak. Determining how the MPB has expanded its range to breach putative barriers, whether physical (nonforested prairie and high elevation of the Rocky Mountains) or climatic (extreme continental climate where temperatures can be below -40 °C), may contribute to our general understanding of range changes as well as management of the current epidemic. Here, we use a panel of 1,536 single nucleotide polymorphisms (SNPs) to assess population genetic structure, connectivity, and signals of selection within this MPB range expansion. Biallelic SNPs in MPB from southwestern Canada revealed higher genetic differentiation and lower genetic connectivity than in the northern part of its range. A total of 208 unique SNPs were identified using different outlier detection tests, of which 32 returned annotations for products with putative functions in cholesterol synthesis, actin filament contraction, and membrane transport. We suggest that MPB has been able to spread beyond its previous range by adjusting its cellular and metabolic functions, with genome scale differentiation enabling populations to better withstand cooler climates and facilitate longer dispersal distances. Our study is the first to assess landscape-wide selective adaptation in an insect. We have shown that interrogation of genomic resources can identify shifts in genetic diversity and putative adaptive signals in this forest pest species.

  9. Isolation and characterization of 16 microsatellite loci in the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Davis, C S; Mock, K E; Bentz, B J; Bromilow, S M; Bartell, N V; Murray, B W; Roe, A D; Cooke, J E K

    2009-05-01

    We isolated 16 polymorphic microsatellite loci in the mountain pine beetle (Dendroctonus ponderosae Hopkins) and developed conditions for amplifying these markers in four multiplex reactions. Three to 14 alleles were detected per locus across two sampled populations. Observed and expected heterozygosities ranged from 0.000 to 0.902 and from 0.100 to 0.830, respectively. Three loci deviated from Hardy-Weinberg equilibrium in one sampled population. One of these loci may be sex linked. These markers will be useful in the study of population structure in this important pest species.

  10. Identification and synthesis of new bicyclic acetals from the mountain pine beetle, Dendroctonus ponderosae Hopkins (Col.: Scol.).

    PubMed

    Francke, W; Schröder, F; Philipp, P; Meyer, H; Sinnwell, V; Gries, G

    1996-03-01

    Head-space volatiles obtained from male mountain pine beetles, Dendroctonus ponderosae, were analyzed by coupled GC-MS and chiral gas chromatography. 5-Ethyl-7-methyl-6,8-dioxabicyclo[3.2.1]octane (6) was found as a new naturally occurring isomer of brevicomin (1). In addition, several stereoisomers of 7-ethyl-5-methyl-6,8-dioxabicyclo[3.2.1]octan-2-ol (11) and 1-(5-methyl-6,8-dioxabicyclo[3.2.1]octyl)ethanol (12) could be identified. Relative and absolute configurations of the compounds were determined by unambiguous syntheses, which are described.

  11. Green leaf volatiles as antiaggregants for the mountain pine beetle,Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae).

    PubMed

    Wilson, I M; Borden, J H; Gries, R; Gries, G

    1996-10-01

    We tested the hypothesis that green leaf volatiles act as antiaggregants for the mountain pine beetle (MPB),Dendroctonus ponderosac Hopkins. In coupled gas chromatographic-electroantennographic detection (GC-EAD) analysis MPB antennae responded to 30 ng doses of all six-carbon green leaf alcohols tested [1-hexanol, (E)-2-hexen-1-ol, (Z)-2-hexen-1-ol, (E)-3-hexen-1-ol, and (Z)-3-hexen-1-ol], but not to the aldehydes, hexanal or (E)-2-hexenal, or to alcohol or aldehyde homologues with more or fewer than six carbon atoms. In field trapping experiments a blend of green leaf alcohols [1-hexanol, (Z)-2-hexen-1-ol, (E)-3-hexen-1-ol and (Z)-3-hexen-1-ol] effectively disrupted the response to attractive semiochemicals; a blend of the aldehydes hexanal and (E)-2-hexenal was inactive. The two best disruptants. (E)-2-hexen-1-ol and (Z)-3-hexen-1-ol, reduced catches of both sexes to levels not significantly different from catches in unbaited control traps. They also reduced the attack on trees baited with attractive MBP pheromones to a level not significantly different from that on unbaited control trees. Neither of the clerid predators captured,Enoclerus sphegeus (F.) norThanasimus undatulus (Say), was repelled by green leaf volatiles. Our results suggest that green leaf alcohols are promising disruptants which may be used to supplement the antiaggregation pheromone, verbenone, in protecting single high-value trees as well as carefully selected stands with low-level populations of MPBs.

  12. Genetic relationships among Leptographium terebrantis and the mycangial fungi of three western Dendroctonus bark beetles.

    PubMed

    Six, Diana L; Harrington, Thomas C; Steimel, Joseph; McNew, Douglas; Paine, T D

    2003-01-01

    Morphology, mitochondrial DNA (mtDNA) restriction fragment polymorphisms (RFLPs) and nuclear DNA (nDNA) fingerprinting were used to clarify relationships among the morphologically similar Ophiostoma and Leptographium species associated with mycangia of three Dendroctonus bark beetles (Ophiostoma clavigerum associated with both D. ponderosae and D. jeffreyi, and L. pyrinum associated with D. adjunctus), as well as a closely related nonmycangial bark beetle associate (L. terebrantis). Most isolates of O. clavigerum form long (40-70 μm), septate conidia, while all isolates of L. terebrantis and L. pyrinum form conidia less than 17.0 μm in length. The conidia of L. pyrinum are pyriform, with truncate bases, while the conidia of the other species form only slightly truncate bases. Conidial masses of L. terebrantis are creamy yellow, while the conidial masses of the other species are white. Nuclear DNA fingerprints resulting from probing PstI restrictions with the oligonucleotide probe (CAC)(5) and HaeIII and MspI restrictions of mtDNA, exhibited three major clusters. In the dendrogram developed from mtDNA RFLPs, the L. pyrinum isolates formed one cluster, while the majority of O. clavigerum isolates, including all D. jeffreyi isolates, formed another. A third cluster was composed of all L. terebrantis isolates, as well as several O. clavigerum isolates from D. ponderosae. The inclusion of some O. clavigerum isolates in the L. terebrantis cluster suggests that horizontal transfer of mtDNA has occurred among these fungi. The nDNA dendrogram also exhibited three clusters, and most isolates of L. pyrinum, L. terebrantis and O. clavigerum grouped separately; however, one isolate of O. clavigerum grouped with the L. terebrantis isolates, while one isolate of L. terebrantis grouped with O. clavigerum. No genetic markers were found that distinguished between O. clavigerum associated with D. ponderosae and O. clavigerum associated with D. jeffreyi. Ophiostoma clavigerum might

  13. Frontalin pheromone biosynthesis in the mountain pine beetle, Dendroctonus ponderosae, and the role of isoprenyl diphosphate synthases.

    PubMed

    Keeling, Christopher I; Chiu, Christine C; Aw, Tidiane; Li, Maria; Henderson, Hannah; Tittiger, Claus; Weng, Hong-Biao; Blomquist, Gary J; Bohlmann, Joerg

    2013-11-19

    The mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most destructive pest of western North American pine forests. Adult males produce frontalin, an eight-carbon antiaggregation pheromone, via the mevalonate pathway, as part of several pheromones that initiate and modulate the mass attack of host trees. Frontalin acts as a pheromone, attractant, or kairomone in most Dendroctonus species, other insects, and even elephants. 6-Methylhept-6-en-2-one, a frontalin precursor, is hypothesized to originate from 10-carbon geranyl diphosphate (GPP), 15-carbon farnesyl diphosphate (FPP), or 20-carbon geranylgeranyl diphosphate (GGPP) via a dioxygenase- or cytochrome P450-mediated carbon-carbon bond cleavage. To investigate the role of isoprenyl diphosphate synthases in pheromone biosynthesis, we characterized a bifunctional GPP/FPP synthase and a GGPP synthase in the mountain pine beetle. The ratio of GPP to FPP produced by the GPP/FPP synthase was highly dependent on the ratio of the substrates isopentenyl diphosphate and dimethylallyl diphosphate used in the assay. Transcript levels in various tissues and life stages suggested that GGPP rather than GPP or FPP is used as a precursor to frontalin. Reduction of transcript levels by RNA interference of the isoprenyl diphosphate synthases identified GGPP synthase as having the largest effect on frontalin production, suggesting that frontalin is derived from a 20-carbon isoprenoid precursor rather than from the 10- or 15-carbon precursors.

  14. In vitro interactions between yeasts and bacteria and the fungal symbionts of the mountain pine beetle (Dendroctonus ponderosae).

    PubMed

    Adams, Aaron S; Six, Diana L; Adams, Sandye M; Holben, William E

    2008-10-01

    Multi-trophic interactions between prokaryotes, unicellular eukaryotes, and ecologically intertwined metazoans are presumably common in nature, yet rarely described. The mountain pine beetle, Dendroctonus ponderosae, is associated with two filamentous fungi, Grosmannia clavigera and Ophiostoma montium. Other microbes, including yeasts and bacteria, are also present in the phloem, but it is not known whether they interact with the symbiotic fungi or the host beetle. To test whether such interactions occur, we performed a suite of in vitro assays. Overall, relative yield of O. montium grown with microbes isolated from larval galleries was significantly greater than when the fungus was grown alone. Conversely, the yield of G. clavigera grown with these same microbes was less than or equal to when it was grown alone, suggesting that O. montium, and at least some microbes in larval galleries, have a mutualistic or commensal relationship, while G. clavigera and those same microbes have an antagonistic relationship. A bacterium isolated from phloem not colonized by beetles was found to inhibit growth of both G. clavigera and O. montium and appears to be an antagonist to both fungi. Our results suggest that bacteria and yeasts likely influence the distribution of mycangial fungi in the host tree, which, in turn, may affect the fitness of D. ponderosae.

  15. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae) outbreak in pine forests.

    PubMed

    Pec, Gregory J; Karst, Justine; Sywenky, Alexandra N; Cigan, Paul W; Erbilgin, Nadir; Simard, Suzanne W; Cahill, James F

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown. PMID:25859663

  16. Rapid Increases in Forest Understory Diversity and Productivity following a Mountain Pine Beetle (Dendroctonus ponderosae) Outbreak in Pine Forests

    PubMed Central

    Pec, Gregory J.; Karst, Justine; Sywenky, Alexandra N.; Cigan, Paul W.; Erbilgin, Nadir; Simard, Suzanne W.; Cahill, James F.

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown. PMID:25859663

  17. Cytochrome P450 complement (CYPome) of Candida oregonensis, a gut-associated yeast of bark beetle, Dendroctonus rhizophagus.

    PubMed

    Hernández-Martínez, Fabiola; Briones-Roblero, Carlos Iván; Nelson, David R; Rivera-Orduña, Flor Nohemí; Zúñiga, Gerardo

    2016-09-01

    Bark beetles (Curculionidae: Scolytinae) and associated microorganisms must overcome a complex tree's defence system, which includes toxic monoterpenes, to successfully complete their life cycle. A number of studies have suggested these microorganisms could have ecological roles related with the nutrition, detoxification, and semiochemical production. In particular, in filamentous fungi symbionts, cytochrome P450 (CYP) have been involved with terpenoid detoxification and biotransformation processes. Candida oregonensis has been isolated from the gut, ovaries, and frass of different bark beetle species, and it is a dominant species in the Dendroctonus rhizophagus gut. In this study, we identify, characterise, and infer the phylogenetic relationships of C. oregonensis CYP genes. The results indicate that the cytochrome P450 complement (CYPome) is composed of nine genes (CYP51F1, CYP61A1, CYP56D1, CYP52A59, CYP52A60, CYP52A61, CYP52A62, CYP5217A8, and CYP5217B1), which might participate in primary metabolic reactions such as sterol biosynthesis, biodegradation of xenobiotic, and resistance to environmental stress. The prediction of the cellular location suggests that these CYPs to be anchored to the plasma membrane, membranes of the endoplasmic reticulum, mitochondria, and peroxisomes. These findings lay the foundation for future studies about the functional role of P450s, not only for yeasts, but also for the insects with which they interact. PMID:27567714

  18. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae) outbreak in pine forests.

    PubMed

    Pec, Gregory J; Karst, Justine; Sywenky, Alexandra N; Cigan, Paul W; Erbilgin, Nadir; Simard, Suzanne W; Cahill, James F

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  19. Electrophysiological and behavioral responses of the bark beetle Dendroctonus rhizophagus to volatiles from host pines and conspecifics.

    PubMed

    Cano-Ramírez, Claudia; Armendáriz-Toledano, Francisco; Macías-Sámano, Jorge E; Sullivan, Brian T; Zúñiga, Gerardo

    2012-05-01

    The bark beetle Dendroctonus rhizophagus is endemic to northwestern Mexico where it kills immature pines < 3 m tall. We report the first investigation of the chemical ecology of this pest of forest regeneration. We used GC-EAD to assess olfactory sensitivity of this species to volatile compounds from: resin of a major host, Pinus arizonica; mid/hindguts of single, gallery-initiating females; and mate-paired males within galleries of attacked host trees in the field. Antennae of both sexes responded to monoterpenes α-pinene, β-pinene and 3-carene as well as to the beetle-derived oxygenated monoterpenes fenchyl alcohol, myrtenal, cis-verbenol, trans-verbenol, verbenone, and myrtenol. These monoterpenes were quantified from pre-emerged D. rhizophagus adults forced to attack host tissue in the laboratory, and from individuals dissected from naturally-attacked hosts at different stages of colonization. In both bioassays, myrtenol and trans-verbenol were the most abundant volatiles, and trans-verbenol was the only one produced in significantly greater quantities by females than males in a naturally-colonized host. Two field experiments were performed to evaluate behavioral responses of D. rhizophagus to antennally-active monoterpenes. Results show that 3-carene was significantly attractive either alone or in a ternary (1:1:1) combination with α-pinene and β-pinene, whereas neither α-pinene nor β-pinene alone were attractive. None of the beetle-associated oxygenated monoterpenes enhanced the attractiveness of the ternary mixture of monoterpenes, while verbenone either alone or combined with the other five oxygenated terpenes reduced D. rhizophagus attraction to the ternary mixture. The results suggest that attraction of D. rhizophagus to the host tree P. arizonica is mediated especially by 3-carene. There was no conclusive evidence for an aggregation or sex attractant pheromone.

  20. Cryptic postzygotic isolation in an eruptive species of bark beetle (Dendroctonus ponderosae).

    PubMed

    Bracewell, Ryan R; Pfrender, Michael E; Mock, Karen E; Bentz, Barbara J

    2011-04-01

    Studies of postzygotic isolation often involve well-differentiated taxa that show a consistent level of incompatibility, thereby limiting our understanding of the initial stages and development of reproductive barriers. Dendroctonus ponderosae provides an informative system because recent evidence suggests that distant populations produce hybrids with reproductive incompatibilities. Dendroctonus ponderosae shows an isolation-by-distance gene flow pattern allowing us to characterize the evolution of postzygotic isolation (e.g., hybrid inviability, hybrid sterility) by crossing populations along a continuum of geographic/genetic divergence. We found little evidence of hybrid inviability among these crosses. However, crosses between geographically distant populations produced sterile males (consistent with Haldane's rule). This effect was not consistent with the fixation of mutations in an isolation-by-distance pattern, but instead is spatially localized. These reproductive barriers are uncorrelated with a reduction in gene flow suggesting their recent development. Crosses between geographically proximal populations bounding the transition from compatibility to hybrid male sterility showed evidence of unidirectional reduction in hybrid male fecundity. Our study describes significant postzygotic isolation occurring across a narrow and molecularly cryptic geographic zone between the states of Oregon and Idaho. This study provides a view of the early stages of postzygotic isolation in a geographically widespread species.

  1. Influence of oleoresin constituents fromPinus ponderosa andPinus jeffreyi on growth of mycangial fungi fromDendroctonus ponderosae andDendroctonus jeffreyi.

    PubMed

    Paine, T D; Hanlon, C C

    1994-10-01

    Dendroctonus jeffreyi andD. ponderosae are morphologically similar sympatric species of pine bark beetles over portions of their geographic ranges; however,D. jeffreyi is monophagous onP. jeffreyi whileD. ponderosae is highly polyphagous. Both species carry a species of mycangial fungi that are also very similar in appearance. Growth of the two mycangial fungi and of the fungusLeptographium terebrantis (associated with the polyphagous and non-tree-killingDendroctonus valens) in the presence of oleoresin constituents of host and nonhost conifers was tested by placing individual chemicals on agar growth medium and by growing the cultures in saturated atmospheres of the chemicals. The fungus associated withD. jeffreyi showed greater tolerance for chemical constituents placed on the growth medium than the other two fungi, and growth after three days was enhanced by heptane, the dominant constituent ofP. jeffreyi oleoresin. Growth of all three species of fungi was reduced by the resin constituents when the chemicals were presented as saturated atmospheres. The results suggest that the influence of the tree on growth of the symbiotic fungi of the bark beetles during the initial attack process may be different than after colonization by the beetles is complete. The difference in the responses of the apparently related species of mycangial fungi may provide some new insight into the evolutionary history of these beetle/mycangial fungus/host tree systems.

  2. Host selection behavior of bark beetles (Coleoptera: Scolytidae) attackingPinus ponderosa, with special emphasis on the western pine beetle,Dendroctonus brevicomis.

    PubMed

    Moeck, H A; Wood, D L; Lindahl, K Q

    1981-01-01

    Detection of weakened hosts from a distance by bark beetles through olfaction was investigated in field experiments. No significant numbers of Scolytidae were attracted to anaerobically treated pine bolts, stem disks, or sugar and ponderosa pine bark including phloem. Treatment of living trees with cacodylic acid induced attacks byDendroctonus brevicomis, D. ponderosae, Ips latidens, Gnathotrichus retusus, andPityophthorus scalptor, beginning two weeks after treatment. There was no significant difference between landing rates ofD. brevicomis andD. ponderosae on screened treated trees and screened controls. There was a significant increase in landing rates ofG. retusus andI. latidens, because both species had penetrated the screen and produced pheromones. Tree frilling alone did not increase the landing rate of bark beetles. Freezing of the lower trunk with dry ice did not increase significantly the landing rate ofD. brevicomis, D. ponderosae, G. retusus, orI. latidens on screened trees, whereas unscreened frozen trees were attacked by all four species. There was no significantly higher landing rate byD. brevicomis, D. ponderosae, I. paraconfusus, I. latidens, G. retusus, orHylurgops subcostulatus on screened trees evidencing symptoms of severe infection by the root pathogenVerticicladiella wagenerii, than on symptornless trees. These experiments show thatD. brevicomis, D. ponderosae, I. paraconfusus, I. latidens, andG. retusus land, apparently indiscriminately, on healthy and stressed hosts. Thus, in these species host discrimination must occur after landing and prior to sustained feeding.

  3. Community structure of gut fungi during different developmental stages of the Chinese white pine beetle (Dendroctonus armandi).

    PubMed

    Hu, Xia; Li, Ming; Chen, Hui

    2015-02-12

    The Chinese white pine beetle is arguably the most destructive forest insect in the Qinling Mountains in Northern China. Little is known about the structure of the fungal communities associated with Dendroctonus armandi, even though this wood-boring insect plays important roles in ecosystem and biological invasion processes that result in huge economic losses in pine forests. The aim of this study was to investigate the fungal community structure present in the galleries and guts of D. armandi at different developmental stages using PCR-denaturing gradient gel electrophoresis (DGGE). Analysis of PCR-amplified 18S rRNA gene fragments of fungi from the guts of D. armandi revealed fungal communities of low complexity that differed according to the developmental stage. Yeast of the genus Candida and the filamentous fungi Ophiostoma predominated in D. armandi and its galleries. In particular, Candida accounted for 56% of the fungal community in the pupal stage. Characterizing the evolution and content of the intestinal microbial community structure in D. armandi may facilitate the development of new pest control strategies.

  4. Community structure of gut fungi during different developmental stages of the Chinese white pine beetle (Dendroctonus armandi)

    PubMed Central

    Hu, Xia; Li, Ming; Chen, Hui

    2015-01-01

    The Chinese white pine beetle is arguably the most destructive forest insect in the Qinling Mountains in Northern China. Little is known about the structure of the fungal communities associated with Dendroctonus armandi, even though this wood-boring insect plays important roles in ecosystem and biological invasion processes that result in huge economic losses in pine forests. The aim of this study was to investigate the fungal community structure present in the galleries and guts of D. armandi at different developmental stages using PCR-denaturing gradient gel electrophoresis (DGGE). Analysis of PCR-amplified 18S rRNA gene fragments of fungi from the guts of D. armandi revealed fungal communities of low complexity that differed according to the developmental stage. Yeast of the genus Candida and the filamentous fungi Ophiostoma predominated in D. armandi and its galleries. In particular, Candida accounted for 56% of the fungal community in the pupal stage. Characterizing the evolution and content of the intestinal microbial community structure in D. armandi may facilitate the development of new pest control strategies. PMID:25672215

  5. Differences in the structure of the gut bacteria communities in development stages of the Chinese white pine beetle (Dendroctonus armandi).

    PubMed

    Hu, Xia; Wang, Chunyan; Chen, Hui; Ma, Junning

    2013-01-01

    The Chinese white pine beetle Dendroctonus armandi Tsai and Li, is arguably the most destructive forest insect in the Qinling Mountains in Northern China. Little is known about the structure of the bacterial communities associated with D. armandi even though this wood-boring insect plays important roles in ecosystem and biological invasion processes that result in huge economic losses in pine forests. The aim of this study was to investigate the composition of the bacterial communities present in the guts of D. armandi at different developmental stages using a culture-independent method involving PCR-denaturing gradient gel electrophoresis (DGGE). Analysis of PCR-amplified 16S rRNA gene fragments of bacteria from the guts of larvae, pupae, and male and female adults revealed bacterial communities of low complexity that differed according to the developmental stage. Citrobacter spp. and Pantoea spp. predominated in larvae and adults, whereas Methylobacterium was the dominant genus at the pupal stage. The main difference between the guts of male and female adults was the greater dominance of Citrobacter in females. Previous studies suggest that the bacterial community associated with D. armandi guts may influence insect development. The data obtained in this study regarding the phylogenetic relationships and the community structure of intestinal bacteria at different developmental stages of the D. armandi life cycle contribute to our understanding of D. armandi and could aid the development of new pest control strategies.

  6. Historical demography and phylogeography of a specialist bark beetle, Dendroctonus pseudotsugae Hopkins (Curculionidae: Scolytinae).

    PubMed

    Ruiz, Enrico A; Rinehart, John E; Hayes, Jane L; Zuñiga, Gerardo

    2010-10-01

    Contemporary distribution of North American species has been shaped by past glaciation events during the Quaternary period. However, their effects were not as severe in the southern Rocky Mountains and Northern Mexico as elsewhere in North America. In this context, we test hypotheses about the historical demography of Dendroctonus pseudotsugae, based on 136 haplotypes of mitochondrial cytochrome oxidase I. The phylogenetic analysis yielded four haplogroups corresponding to northwestern United States and southwestern Canada (NUS), southwestern United States (Arizona, SUS), northwestern Mexico (Sierra Madre Occidental, SMOC), and northeastern Mexico (Sierra Madre Oriental, SMOR). Predictions of demographic expansion were examined through neutrality tests against population growth and mismatch distribution. Results showed that the NUS and SMOC haplogroups have experienced demographic expansion events, whereas the SUS and SMOR haplogroups have not. Divergence times between pairs of haplogroups were estimated from early to middle Pleistocene. The longer divergence time between NUS and all other haplogroups could be the result of refugia within the Pacific Northwest and northern Rocky Mountains and long-term isolation from southernmost populations in Mexico. The results obtained in this study are in agreement with the evolutionary history of the host Douglas-fir, as the warmer climates of interglacial periods pushed conifers northward of Colorado, New Mexico, and Arizona, whereas environmental changes reduced the population size of Douglas-fir and forced fragmentation of distribution range southward into northern Mexico. PMID:22546468

  7. Transcriptome and full-length cDNA resources for the mountain pine beetle, Dendroctonus ponderosae Hopkins, a major insect pest of pine forests.

    PubMed

    Keeling, Christopher I; Henderson, Hannah; Li, Maria; Yuen, Mack; Clark, Erin L; Fraser, Jordie D; Huber, Dezene P W; Liao, Nancy Y; Docking, T Roderick; Birol, Inanc; Chan, Simon K; Taylor, Greg A; Palmquist, Diana; Jones, Steven J M; Bohlmann, Joerg

    2012-08-01

    Bark beetles (Coleoptera: Curculionidae: Scolytinae) are major insect pests of many woody plants around the world. The mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, is a significant historical pest of western North American pine forests. It is currently devastating pine forests in western North America--particularly in British Columbia, Canada--and is beginning to expand its host range eastward into the Canadian boreal forest, which extends to the Atlantic coast of North America. Limited genomic resources are available for this and other bark beetle pests, restricting the use of genomics-based information to help monitor, predict, and manage the spread of these insects. To overcome these limitations, we generated comprehensive transcriptome resources from fourteen full-length enriched cDNA libraries through paired-end Sanger sequencing of 100,000 cDNA clones, and single-end Roche 454 pyrosequencing of three of these cDNA libraries. Hybrid de novo assembly of the 3.4 million sequences resulted in 20,571 isotigs in 14,410 isogroups and 246,848 singletons. In addition, over 2300 non-redundant full-length cDNA clones putatively containing complete open reading frames, including 47 cytochrome P450s, were sequenced fully to high quality. This first large-scale genomics resource for bark beetles provides the relevant sequence information for gene discovery; functional and population genomics; comparative analyses; and for future efforts to annotate the MPB genome. These resources permit the study of this beetle at the molecular level and will inform research in other Dendroctonus spp. and more generally in the Curculionidae and other Coleoptera.

  8. Electroantennograms by mountain pine beetles,Dendroctonus ponderosae Hopkins, exposed to selected chiral semiochemicals.

    PubMed

    Whitehead, A T; Del Scott, T; Schmitz, R F; Mori, K

    1989-07-01

    Electroantennograms (EAGs) were recorded fromD. ponderosae to the enantiomers of the terpenoid bark-beetle pheromonestrans-verbenol,cis-verbenol, verbenone, and the bicyclic ketals frontalin,exo-brevicomin, andendo-brevicomin. Male and female responses to enantiomers of the terpenoids differed significantly only at the two highest concentrations. No sex differences were seen in response to the bicyclic ketals. Significantly different responses to the enantiomers of all the chemicals, except frontalin, were noted over at least part of the dosage-response ranges tested. The negative antipode for all of the terpenoids elicited higher responses, while for the bicyclic ketals, the positive antipode effected the largest responses except for the two highest concentrations ofexo-brevicomin.

  9. Electroantennogram responses by mountain pine beetles,Dendroctonus ponderosae Hopkins, exposed to selected semiochemicals.

    PubMed

    Whitehead, A T

    1986-07-01

    Electroantennograms (EAGs) were obtained forD. ponderosae to the bark beetle pheromonestrans-verbenol,cis-verbenol,exo-brevicomin,endo-brevicomin, frontalin, verbenone; to the kairomones, α-pinene, β-pinene, camphene, Δ-3-carene, limonene, myrcene; to a blend (1∶1∶1) oftrans-verbenol,exo-brevicomin, and myrcene; and to diacetone-alcohol. Male and female responses, in general, did not differ significantly over the whole EAG dose-response curves but differed at a few concentrations on many of the curves. There were more differences noted for pheromones than kairomones. The blend yielded among the largest EAGs in both sexes and appeared to show synergism. Responses of females were lower than those for males in most instances. Significant differences in responses by the two sexes were much fewer for the kairomones than the pheromones. EAG recovery rates tested at only one concentration showed significant differences between males and females for three pheromones,trans-verbenol,cis-verbenol, and verbenone, and two kairomones, camphene and Δ-3-carene. Thresholds were quite low for most of the odorants exceptcis-verbenol, camphene, verbenone, and diacetone-alcohol in females, andcis-verbenol, verbenone, α-pinene, and diacetone-alcohol in males. The results, using at least one EAG parameter, support behavioral and field studies involvingexo-brevicomin,trans-verbenol, frontalin, and the blend.

  10. Responses of bark beetle-associated bacteria to host monoterpenes and their relationship to insect life histories.

    PubMed

    Adams, Aaron S; Boone, Celia K; Bohlmann, Jörg; Raffa, Kenneth F

    2011-08-01

    Bark beetles that colonize living conifers and their microbial associates encounter constitutive and induced chemical defenses of their host. Monoterpene hydrocarbons comprise a major component of these allelochemicals, and many are antibiotic to insects, fungi, and bacteria. Some bark beetle species exhaust these defenses by killing their host through mass attacks mediated by aggregation pheromones. Others lack adult aggregation pheromones and do not engage in pheromone-mediated mass attacks, but rather have the ability to complete development within live hosts. In the former species, the larvae develop in tissue largely depleted of host terpenes, whereas in the latter exposure to these compounds persists throughout development. A substantial literature exists on how monoterpenes affect bark beetles and their associated fungi, but little is known of how they affect bacteria, which in turn can influence beetle performance in various manners. We tested several bacteria from two bark beetle species for their ability to grow in the presence of a diversity of host monoterpenes. Bacteria were isolated from the mountain pine beetle, Dendroctonus ponderosae Hopkins, which typically kills trees during colonization, and the red turpentine beetle, Dendroctonus valens LeConte, which often lives in their host without causing mortality. Bacteria from D. ponderosae were gram-positive Actinobacteria and Bacilli; one yeast also was tested. Bacteria from D. valens were Actinobacteria, Bacilli, and γ-Proteobacteria. Bacteria from D. valens were more tolerant of monoterpenes than were those from D. ponderosae. Bacteria from D. ponderosae did not grow in the presence of α-pinene and 3-carene, and grew in, but were inhibited by, β-pinene and β-phellandrene. Limonene and myrcene had little inhibitory effect on bacteria from either beetle species. Tolerance to these antibiotic compounds appears to have resulted from adaptation to living in a terpene-rich environment.

  11. Large shift in symbiont assemblage in the invasive red turpentine beetle.

    PubMed

    Taerum, Stephen J; Duong, Tuan A; de Beer, Z Wilhelm; Gillette, Nancy; Sun, Jiang-Hua; Owen, Donald R; Wingfield, Michael J

    2013-01-01

    Changes in symbiont assemblages can affect the success and impact of invasive species, and may provide knowledge regarding the invasion histories of their vectors. Bark beetle symbioses are ideal systems to study changes in symbiont assemblages resulting from invasions. The red turpentine beetle (Dendroctonus valens) is a bark beetle species that recently invaded China from its native range in North America. It is associated with ophiostomatalean fungi in both locations, although the fungi have previously been well-surveyed only in China. We surveyed the ophiostomatalean fungi associated with D. valens in eastern and western North America, and identified the fungal species using multi-gene phylogenies. From the 307 collected isolates (147 in eastern North America and 160 in western North America), we identified 20 species: 11 in eastern North America and 13 in western North America. Four species were shared between eastern North America and western North America, one species (Ophiostoma floccosum) was shared between western North America and China, and three species (Grosmannia koreana, Leptographium procerum, and Ophiostoma abietinum) were shared between eastern North America and China. Ophiostoma floccosum and O. abietinum have worldwide distributions, and were rarely isolated from D. valens. However, G. koreana and L. procerum are primarily limited to Asia and North America respectively. Leptographium procerum, which is thought to be native to North America, represented >45% of the symbionts of D. valens in eastern North America and China, suggesting D. valens may have been introduced to China from eastern North America. These results are surprising, as previous population genetics studies on D. valens based on the cytochrome oxidase I gene have suggested that the insect was introduced into China from western North America.

  12. The legacy of attack: implications of high phloem resin monoterpene levels in lodgepole pines following mass attack by mountain pine beetle, Dendroctonus ponderosae Hopkins.

    PubMed

    Clark, E L; Huber, D P W; Carroll, A L

    2012-04-01

    The mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most serious pest of pines (Pinus) in western North America. Host pines protect themselves from attack by producing a complex mixture of terpenes in their resin. We sampled lodgepole pine (Pinus contorta variety latifolia) phloem resin at four widely separated locations in the interior of British Columbia, Canada, both just before (beginning of July) and substantially after (end of August) the mountain pine beetle dispersal period. The sampled trees then were observed the next spring for evidence of survival, and the levels of seven resin monoterpenes were compared between July and August samples. Trees that did not survive consistently had significantly higher phloem resin monoterpene levels at the end of August compared with levels in July. Trees that did survive mainly did not exhibit a significant difference between the two sample dates. The accumulation of copious defense-related secondary metabolites in the resin of mountain pine beetle-killed lodgepole pine has important implications for describing the environmental niche that the beetle offspring survive in as well as that of parasitoids, predators, and other associates. PMID:22507014

  13. The legacy of attack: implications of high phloem resin monoterpene levels in lodgepole pines following mass attack by mountain pine beetle, Dendroctonus ponderosae Hopkins.

    PubMed

    Clark, E L; Huber, D P W; Carroll, A L

    2012-04-01

    The mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most serious pest of pines (Pinus) in western North America. Host pines protect themselves from attack by producing a complex mixture of terpenes in their resin. We sampled lodgepole pine (Pinus contorta variety latifolia) phloem resin at four widely separated locations in the interior of British Columbia, Canada, both just before (beginning of July) and substantially after (end of August) the mountain pine beetle dispersal period. The sampled trees then were observed the next spring for evidence of survival, and the levels of seven resin monoterpenes were compared between July and August samples. Trees that did not survive consistently had significantly higher phloem resin monoterpene levels at the end of August compared with levels in July. Trees that did survive mainly did not exhibit a significant difference between the two sample dates. The accumulation of copious defense-related secondary metabolites in the resin of mountain pine beetle-killed lodgepole pine has important implications for describing the environmental niche that the beetle offspring survive in as well as that of parasitoids, predators, and other associates.

  14. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae).

    PubMed

    Clark, Erin L; Pitt, Caitlin; Carroll, Allan L; Lindgren, B Staffan; Huber, Dezene P W

    2014-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle's historic range (central BC) to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB) in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC) and one population of jack pine (AB) were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels - a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle - were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the insect to persist in

  15. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae).

    PubMed

    Clark, Erin L; Pitt, Caitlin; Carroll, Allan L; Lindgren, B Staffan; Huber, Dezene P W

    2014-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle's historic range (central BC) to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB) in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC) and one population of jack pine (AB) were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels - a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle - were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the insect to persist in

  16. Cytochrome P450s from the Chinese white pine beetle, Dendroctonus armandi (Curculionidae: Scolytinae): Expression profiles of different stages and responses to host allelochemicals.

    PubMed

    Dai, Lulu; Ma, Mingyuan; Wang, Chunyan; Shi, Qi; Zhang, Ranran; Chen, Hui

    2015-10-01

    Bark beetles oxidize the defensive allelochemicals from their host trees to both detoxify and convert these materials into components of their pheromone system. The ability of this insect to adapt to its chemical environment might be explained by the action of major detoxification enzymes such as cytochrome P450s (or CYPs). Sixty-four sequences coding for P450s were identified, and most of the transcripts were found to be expressed in the larvae, pupae and adults of Dendroctonus armandi. To gain information on how these genes help D. armandi overcome the host defense, differential transcript levels of the CYP genes were observed between sexes and within the sexes. Significant differences were observed among developmental stages, in feeding on the phloem of Pinus armandi and in exposure to stimuli ((±)-α-pinene, (S)-(-)-α-pinene, (S)-(-)-β-pinene, (+)-3-carene, (±)-limonene and turpentine oil) for 8 h. We investigated the effect of sex and generations on the survivorship of individual D. armandi that were exposed to host volatiles at concentrations comparable to constitutive and induced levels of defense using fumigant exposure to understand the ability of the beetles to tolerate host defensive chemicals. The differential transcript accumulation patterns of CYP genes of these bark beetle provided insight into the ecological interactions of D. armandi with its host pine. PMID:26319543

  17. First in line or first in time? Effects of settlement order and arrival date on reproduction in a group-living beetle Dendroctonus ponderosae.

    PubMed

    Latty, Tanya M; Reid, Mary L

    2009-05-01

    1. In group-living organisms, individuals that initiate aggregations, termed pioneers, may suffer higher mortality costs than individuals that join established aggregations. Here we examine the hypothesis that aggregation initiators achieve higher reproductive success in the early phases of colonization, potentially through lower competition and increased access to the resource (finder's advantage), and that this benefit is sufficient to outweigh the costs of pioneering. 2. We also examine the role of arrival date (irrespective of order within the aggregation) on reproductive success, because individuals in seasonal environments may gain an advantage by arriving early. We test these hypotheses using mountain pine beetles, Dendroctonus ponderosae (Coleoptera: Curculionidae, Scolytinae), an obligately aggregating insect wherein pioneers suffer high mortality due to tree defences. We measured reproductive success at the start of winter when most components of final offspring number were likely to be determined. 3. Surviving pioneers that successfully recruited conspecifics had smaller broods than individuals that joined aggregations, refuting our hypothesis. The later that a beetle settled within an aggregation, the higher its reproductive success. However, beetles that settled early in the season produced more offspring than those that settled later in the season, and this effect was generally stronger than settlement order within an aggregation. Our study highlights the importance of examining the effects of both settlement order and arrival date on the costs and benefits of pioneering aggregations.

  18. Comparison of lodgepole and jack pine resin chemistry: implications for range expansion by the mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae)

    PubMed Central

    Pitt, Caitlin; Carroll, Allan L.; Lindgren, B. Staffan; Huber, Dezene P.W.

    2014-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a significant pest of lodgepole pine in British Columbia (BC), where it has recently reached an unprecedented outbreak level. Although it is native to western North America, the beetle can now be viewed as a native invasive because for the first time in recorded history it has begun to reproduce in native jack pine stands within the North American boreal forest. The ability of jack pine trees to defend themselves against mass attack and their suitability for brood success will play a major role in the success of this insect in a putatively new geographic range and host. Lodgepole and jack pine were sampled along a transect extending from the beetle’s historic range (central BC) to the newly invaded area east of the Rocky Mountains in north-central Alberta (AB) in Canada for constitutive phloem resin terpene levels. In addition, two populations of lodgepole pine (BC) and one population of jack pine (AB) were sampled for levels of induced phloem terpenes. Phloem resin terpenes were identified and quantified using gas chromatography. Significant differences were found in constitutive levels of terpenes between the two species of pine. Constitutive α-pinene levels – a precursor in the biosynthesis of components of the aggregation and antiaggregation pheromones of mountain pine beetle – were significantly higher in jack pine. However, lower constitutive levels of compounds known to be toxic to bark beetles, e.g., 3-carene, in jack pine suggests that this species could be poorly defended. Differences in wounding-induced responses for phloem accumulation of five major terpenes were found between the two populations of lodgepole pine and between lodgepole and jack pine. The mountain pine beetle will face a different constitutive and induced phloem resin terpene environment when locating and colonizing jack pine in its new geographic range, and this may play a significant role in the ability of the insect to

  19. Isolation of some pathogenic bacteria from the great spruce bark beetle, Dendroctonus micans and its specific predator, Rhizophagus grandis.

    PubMed

    Yaman, M; Ertürk, O; Aslan, I

    2010-01-01

    Some bacteria were isolated from Dendroctonus micans and its specific predator, Rhizophagus grandis. Six bacteria from D. micans were identified as Bacillus pumilus, Enterobacter intermedius, Citrobacter freundii, Cellulomonas flavigena, Microbacterium liquefaciens and Enterobacter amnigenus, three bacteria from R. grandis as Klebsiella pneumoniae, Pantoea agglomerans and Serratia grimesii, on the basis of fatty acid methyl ester analysis and carbon utilization profile by using Microbial Identification and Biolog Microplate Systems. Their insecticidal effects were tested on larvae and adults of D. micans.

  20. Response of mountain pine beetle,Dendroctonus ponderosae Hopkins, and pine engraver,Ips pint (SAY), to ipsdienol in southwestern British Columbia.

    PubMed

    Hunt, D W; Borden, J H

    1988-01-01

    In bioassays conducted with walking beetles in the laboratory (S)-(+)-, (R)-(-)-, and (±)-ipsdienol were attractive alone, but reduced the attraction of both sexes of the mountain pine beetle,Dendroctonus ponderosae Hopkins, to extracts of female frass. Field trapping studies indicated that attraction ofD. ponderosae to a stimulus composed of myrcene +trans-verbenol +exo-brevicomin was significantly reduced with the addition of (±)- and sometimes (S)-(±)-ipsdienol. Thus, (S)-(+)-ipsdienol produced by males of this species may act as an antiaggregation pheromone. (S)-(+)-Ips-dienol is thought to function as a repellent allomone against the pine engraver,Ips pini (Say), in regions whereI. pini utilizes (R)-(-)-ipsdienol as an aggregation pheromone. However, in southwestern British ColumbiaI. pini was attracted to the (±)-ipsdienol used in field bioassays ofD. ponderosae, a finding consistent with the production of both enantiomers byI. pini in this region. When presented with the ternary semiochemical bait forD. ponderosae, (±)-ipsdienol was not attractive toI. pini. Thus, the activity of (S)-(+)-ipsdienol as a repellent allomone againstI. pini seems to be replaced in southwestern British Columbia by the inhibitory effects of myrcene,trans-verbenol,exo-brevicomin, or some combination thereof.

  1. Photoisomerization of antiaggregation pheromone verbenone: Biological and practical implications with respect to the mountain pine beetle,Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae).

    PubMed

    Kostyk, B C; Borden, J H; Gries, G

    1993-08-01

    Release of the antiaggregation pheromone, verbenone, at 3.8 mg/ day from a concentrated source within a multiple-funnel trap completely inhibited response by the mountain pine beetle (MPB),Dendroctonus ponderosae Hopkins, to attractive semiochemical lures. When aerial applications were simulated and verbenone was released at the same rate from beads lying in a 2×2-m area on the forest floor 15-35 cm below a trap, the response of the MPB was inhibited by only 50%. This reduced inhibition may be explained in part by the photoisomerism of verbenone. When exposed to full sunlight on two occasions, the times required for 50% of verbenone vapors to be converted to chrysanthenone were 75 and 100 min, respectively. Trap and tree-baiting experiments indicated no biological activity of chrysanthenone. Rapid photoisomerization could reduce the concentration of verbenone below biologically active levels and would allow the MPB to colonize trees close to already occupied hosts, contributing to the characteristic clumped distribution of MPB attack. The rate of verbenone photoisomerization may vary according to geographic location, stand elevation and density, and should be considered before verbenone is applied to control the MPB and other bark beetles.

  2. Quantitative metabolome, proteome and transcriptome analysis of midgut and fat body tissues in the mountain pine beetle, Dendroctonus ponderosae Hopkins, and insights into pheromone biosynthesis.

    PubMed

    Keeling, Christopher I; Li, Maria; Sandhu, Harpreet K; Henderson, Hannah; Yuen, Macaire Man Saint; Bohlmann, Jörg

    2016-03-01

    Bark beetles (Coleoptera: Scolytinae) are pests of many forests around the world. The mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, is a significant pest of western North American pine forests. The MPB is able to overcome the defences of pine trees through pheromone-assisted aggregation that results in a mass attack of host trees. These pheromones, both male and female produced, are believed to be biosynthesized in the midgut and/or fat bodies of these insects. We used metabolite analysis, quantitative proteomics (iTRAQ) and transcriptomics (RNA-seq) to identify proteins and transcripts differentially expressed between sexes and between tissues when treated with juvenile hormone III. Juvenile hormone III induced frontalin biosynthesis in males and trans-verbenol biosynthesis in females, as well as affected the expression of many proteins and transcripts in sex- and tissue-specific ways. Based on these analyses, we identified candidate genes involved in the biosynthesis of frontalin, exo-brevicomin, and trans-verbenol pheromones.

  3. CYP345E2, an antenna-specific cytochrome P450 from the mountain pine beetle, Dendroctonus ponderosae Hopkins, catalyses the oxidation of pine host monoterpene volatiles.

    PubMed

    Keeling, Christopher I; Henderson, Hannah; Li, Maria; Dullat, Harpreet K; Ohnishi, Toshiyuki; Bohlmann, Jörg

    2013-12-01

    The mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) is a significant pest of western North American pine forests. This beetle responds to pheromones and host volatiles in order to mass attack and thus overcome the terpenoid chemical defences of its host. The ability of MPB antennae to rapidly process odorants is necessary to avoid odorant receptor saturation and thus the enzymes responsible for odorant clearance are an important aspect of host colonization. An antenna-specific cytochrome P450, DponCYP345E2, is the most highly expressed transcript in adult MPB antenna. In in vitro assays with recombinant enzyme, DponCYP345E2 used several pine host monoterpenes as substrates, including (+)-(3)-carene, (+)-β-pinene, (-)-β-pinene, (+)-limonene, (-)-limonene, (-)-camphene, (+)-α-pinene, (-)-α-pinene, and terpinolene. The substrates were epoxidized or hydroxylated, depending upon the substrate. To complement DponCYP345E2, we also functionally characterized the NADPH-dependent cytochrome P450 reductase and the cytochrome b5 from MPB. DponCYP345E2 is the first cytochrome P450 to be functionally characterized in insect olfaction and in MPB.

  4. Proteomics indicators of the rapidly shifting physiology from whole mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae), adults during early host colonization.

    PubMed

    Pitt, Caitlin; Robert, Jeanne A; Bonnett, Tiffany R; Keeling, Christopher I; Bohlmann, Jörg; Huber, Dezene P W

    2014-01-01

    We developed proteome profiles for host colonizing mountain pine beetle adults, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae). Adult insects were fed in pairs on fresh host lodgepole pine, Pinus contorta Dougl. ex Loud, phloem tissue. The proteomes of fed individuals were monitored using iTRAQ and compared to those of starved beetles, revealing 757 and 739 expressed proteins in females and males, respectively, for which quantitative information was obtained. Overall functional category distributions were similar for males and females, with the majority of proteins falling under carbohydrate metabolism (glycolysis, gluconeogenesis, citric acid cycle), structure (cuticle, muscle, cytoskeleton), and protein and amino acid metabolism. Females had 23 proteins with levels that changed significantly with feeding (p<0.05, FDR<0.20), including chaperones and enzymes required for vitellogenesis. In males, levels of 29 proteins changed significantly with feeding (p<0.05, FDR<0.20), including chaperones as well as motor proteins. Only two proteins, both chaperones, exhibited a significant change in both females and males with feeding. Proteins with differential accumulation patterns in females exhibited higher fold changes with feeding than did those in males. This difference may be due to major and rapid physiological changes occurring in females upon finding a host tree during the physiological shift from dispersal to reproduction. The significant accumulation of chaperone proteins, a cytochrome P450, and a glutathione S-transferase, indicate secondary metabolite-induced stress physiology related to chemical detoxification during early host colonization. The females' activation of vitellogenin only after encountering a host indicates deliberate partitioning of resources and a balancing of the needs of dispersal and reproduction. PMID:25360753

  5. Proteomics indicators of the rapidly shifting physiology from whole mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae), adults during early host colonization.

    PubMed

    Pitt, Caitlin; Robert, Jeanne A; Bonnett, Tiffany R; Keeling, Christopher I; Bohlmann, Jörg; Huber, Dezene P W

    2014-01-01

    We developed proteome profiles for host colonizing mountain pine beetle adults, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae). Adult insects were fed in pairs on fresh host lodgepole pine, Pinus contorta Dougl. ex Loud, phloem tissue. The proteomes of fed individuals were monitored using iTRAQ and compared to those of starved beetles, revealing 757 and 739 expressed proteins in females and males, respectively, for which quantitative information was obtained. Overall functional category distributions were similar for males and females, with the majority of proteins falling under carbohydrate metabolism (glycolysis, gluconeogenesis, citric acid cycle), structure (cuticle, muscle, cytoskeleton), and protein and amino acid metabolism. Females had 23 proteins with levels that changed significantly with feeding (p<0.05, FDR<0.20), including chaperones and enzymes required for vitellogenesis. In males, levels of 29 proteins changed significantly with feeding (p<0.05, FDR<0.20), including chaperones as well as motor proteins. Only two proteins, both chaperones, exhibited a significant change in both females and males with feeding. Proteins with differential accumulation patterns in females exhibited higher fold changes with feeding than did those in males. This difference may be due to major and rapid physiological changes occurring in females upon finding a host tree during the physiological shift from dispersal to reproduction. The significant accumulation of chaperone proteins, a cytochrome P450, and a glutathione S-transferase, indicate secondary metabolite-induced stress physiology related to chemical detoxification during early host colonization. The females' activation of vitellogenin only after encountering a host indicates deliberate partitioning of resources and a balancing of the needs of dispersal and reproduction.

  6. Genetic variation of lodgepole pine, Pinus contorta var. latifolia, chemical and physical defenses that affect mountain pine beetle, Dendroctonus ponderosae, attack and tree mortality.

    PubMed

    Ott, Daniel S; Yanchuk, Alvin D; Huber, Dezene P W; Wallin, Kimberly F

    2011-09-01

    Plant secondary chemistry is determined by both genetic and environmental factors, and while large intraspecific variation in secondary chemistry has been reported frequently, the levels of genetic variation of many secondary metabolites in forest trees in the context of potential resistance against pests have been rarely investigated. We examined the effect of tree genotype and environment/site on the variation in defensive secondary chemistry of lodgepole pine, Pinus contorta var. latifolia, against the fungus, Grosmannia clavigera (formerly known as Ophiostoma clavigerum), associated with the mountain pine beetle, Dendroctonus ponderosae. Terpenoids were analyzed in phloem samples from 887, 20-yr-old trees originating from 45 half-sibling families planted at two sites. Samples were collected both pre- and post-inoculation with G. clavigera. Significant variation in constitutive and induced terpenoid compounds was attributed to differences among families. The response to the challenge inoculation with G. clavigera was strong for some individual compounds, but primarily for monoterpenoids. Environment (site) also had a significant effect on the accumulation of some compounds, whereas for others, no significant environmental effect occurred. However, for a few compounds significant family x environment interactions were found. These results suggest that P. c. latifolia secondary chemistry is under strong genetic control, but the effects depend on the individual compounds and whether or not they are expressed constitutively or following induction. PMID:21845434

  7. Genetic variation of lodgepole pine, Pinus contorta var. latifolia, chemical and physical defenses that affect mountain pine beetle, Dendroctonus ponderosae, attack and tree mortality.

    PubMed

    Ott, Daniel S; Yanchuk, Alvin D; Huber, Dezene P W; Wallin, Kimberly F

    2011-09-01

    Plant secondary chemistry is determined by both genetic and environmental factors, and while large intraspecific variation in secondary chemistry has been reported frequently, the levels of genetic variation of many secondary metabolites in forest trees in the context of potential resistance against pests have been rarely investigated. We examined the effect of tree genotype and environment/site on the variation in defensive secondary chemistry of lodgepole pine, Pinus contorta var. latifolia, against the fungus, Grosmannia clavigera (formerly known as Ophiostoma clavigerum), associated with the mountain pine beetle, Dendroctonus ponderosae. Terpenoids were analyzed in phloem samples from 887, 20-yr-old trees originating from 45 half-sibling families planted at two sites. Samples were collected both pre- and post-inoculation with G. clavigera. Significant variation in constitutive and induced terpenoid compounds was attributed to differences among families. The response to the challenge inoculation with G. clavigera was strong for some individual compounds, but primarily for monoterpenoids. Environment (site) also had a significant effect on the accumulation of some compounds, whereas for others, no significant environmental effect occurred. However, for a few compounds significant family x environment interactions were found. These results suggest that P. c. latifolia secondary chemistry is under strong genetic control, but the effects depend on the individual compounds and whether or not they are expressed constitutively or following induction.

  8. Large woody debris and salmonid habitat in the Anchor River basin, Alaska, following an extensive spruce beetle (Dendroctonus rufipennis) outbreak

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A widespread and intense spruce beetle outbreak has killed most of the mature white spruce trees across many watersheds in south-central Alaska. To investigate the potential habitat impacts in a salmon stream, we characterized the current abundance and species composition of large woody debris (LWD...

  9. Spatial genetic structure of the mountain pine beetle (Dendroctonus ponderosae) outbreak in western Canada: historical patterns and contemporary dispersal.

    PubMed

    Gayathri Samarasekera, G D N; Bartell, Nicholas V; Lindgren, B Staffan; Cooke, Janice E K; Davis, Corey S; James, Patrick M A; Coltman, David W; Mock, Karen E; Murray, Brent W

    2012-06-01

    Environmental change has a wide range of ecological consequences, including species extinction and range expansion. Many studies have shown that insect species respond rapidly to climatic change. A mountain pine beetle epidemic of record size in North America has led to unprecedented mortality of lodgepole pine, and a significant range expansion to the northeast of its historic range. Our goal was to determine the spatial genetic variation found among outbreak population from which genetic structure, and dispersal patterns may be inferred. Beetles from 49 sampling locations throughout the outbreak area in western Canada were analysed at 13 microsatellite loci. We found significant north-south population structure as evidenced by: (i) Bayesian-based analyses, (ii) north-south genetic relationships and diversity gradients; and (iii) a lack of isolation-by-distance in the northernmost cluster. The north-south structure is proposed to have arisen from the processes of postglacial colonization as well as recent climate-driven changes in population dynamics. Our data support the hypothesis of multiple sources of origin for the outbreak and point to the need for population specific information to improve our understanding and management of outbreaks. The recent range expansion across the Rocky Mountains into the jack/lodgepole hybrid and pure jack pine zones of northern Alberta is consistent with a northern British Columbia origin. We detected no loss of genetic variability in these populations, indicating that the evolutionary potential of mountain pine beetle to adapt has not been reduced by founder events. This study illustrates a rapid range-wide response to the removal of climatic constraints, and the potential for range expansion of a regional population.

  10. Perceptions of ecological risk associated with mountain pine beetle (Dendroctonus ponderosae) infestations in Banff and Kootenay National Parks of Canada.

    PubMed

    McFarlane, Bonita L; Watson, David O T; Witson, David O T

    2008-02-01

    Western Canada is experiencing an unprecedented outbreak of the mountain pine beetle (MPB). The MPB has the potential to impact some of Canada's national parks by affecting park ecosystems and the visitor experience. Controls have been initiated in some parks to lessen the impacts and to prevent the beetle from spreading beyond park boundaries. We examine the perception of ecological risk associated with MPB in two of Canada's national parks, the factors affecting perceptions of risk, and the influence of risk judgments on support for controlling MPB outbreaks in national parks. Data were collected using two studies of park visitors: a mail survey in 2003 and an onsite survey in 2005. The MPB was rated as posing a greater risk to the health and productivity of park ecosystems than anthropogenic hazards and other natural disturbance agents. Visitors who were familiar with MPB rated the ecological and visitor experience impacts as negative, unacceptable, and eliciting negative emotion. Knowledge and residency were the most consistent predictors of risk judgments. Of knowledge, risk, and demographic variables, only sex and risk to ecosystem domains influenced support for controlling the MPB in national parks. Implications for managing MPB in national parks, visitor education, and ecological integrity are discussed.

  11. Adaptive and neutral markers both show continent-wide population structure of mountain pine beetle (Dendroctonus ponderosae).

    PubMed

    Batista, Philip D; Janes, Jasmine K; Boone, Celia K; Murray, Brent W; Sperling, Felix A H

    2016-09-01

    Assessments of population genetic structure and demographic history have traditionally been based on neutral markers while explicitly excluding adaptive markers. In this study, we compared the utility of putatively adaptive and neutral single-nucleotide polymorphisms (SNPs) for inferring mountain pine beetle population structure across its geographic range. Both adaptive and neutral SNPs, and their combination, allowed range-wide structure to be distinguished and delimited a population that has recently undergone range expansion across northern British Columbia and Alberta. Using an equal number of both adaptive and neutral SNPs revealed that adaptive SNPs resulted in a stronger correlation between sampled populations and inferred clustering. Our results suggest that adaptive SNPs should not be excluded prior to analysis from neutral SNPs as a combination of both marker sets resulted in better resolution of genetic differentiation between populations than either marker set alone. These results demonstrate the utility of adaptive loci for resolving population genetic structure in a nonmodel organism. PMID:27648243

  12. Adaptive and neutral markers both show continent-wide population structure of mountain pine beetle (Dendroctonus ponderosae).

    PubMed

    Batista, Philip D; Janes, Jasmine K; Boone, Celia K; Murray, Brent W; Sperling, Felix A H

    2016-09-01

    Assessments of population genetic structure and demographic history have traditionally been based on neutral markers while explicitly excluding adaptive markers. In this study, we compared the utility of putatively adaptive and neutral single-nucleotide polymorphisms (SNPs) for inferring mountain pine beetle population structure across its geographic range. Both adaptive and neutral SNPs, and their combination, allowed range-wide structure to be distinguished and delimited a population that has recently undergone range expansion across northern British Columbia and Alberta. Using an equal number of both adaptive and neutral SNPs revealed that adaptive SNPs resulted in a stronger correlation between sampled populations and inferred clustering. Our results suggest that adaptive SNPs should not be excluded prior to analysis from neutral SNPs as a combination of both marker sets resulted in better resolution of genetic differentiation between populations than either marker set alone. These results demonstrate the utility of adaptive loci for resolving population genetic structure in a nonmodel organism.

  13. Changing temperatures influence suitability for modeled mountain pine beetle (Dendroctonus ponderosae) outbreaks in the western United States

    NASA Astrophysics Data System (ADS)

    Hicke, Jeffrey A.; Logan, Jesse A.; Powell, James; Ojima, Dennis S.

    2006-06-01

    Insect outbreaks are significant disturbances in forests of the western United States, with infestation comparable in area to fire. Outbreaks of mountain pine beetle (Dendroctonusponderosae Hopkins) require life cycles of one year with synchronous emergence of adults from host trees at an appropriate time of year (termed "adaptive seasonality") to overwhelm tree defenses. The annual course of temperature plays a major role in governing life stage development and imposing synchrony on mountain pine beetle populations. Here we apply a process-based model of adaptive seasonality across the western United States using gridded daily temperatures from the Vegetation/Ecosystem Modeling and Analysis Project (VEMAP) over the period 1895-2100. Historical locations of modeled adaptive seasonality overlay much of the distribution of lodgepole pine (Pinus contorta Douglas), a favored host, indicating that suitable temperatures for outbreak occurred in areas of host availability. A range of suitable temperatures, both in the mean and over an annual cycle, resulted in adaptive seasonality. Adaptive seasonality typically occurred when mean annual temperatures were 3°-6°C, but also included locations where mean temperatures were as low as 1°C or as high as 11°C, primarily as a result of variability in winter temperatures. For most locations, years of adaptive seasonality were uncommon during 1895-1993. We analyzed historical temperatures and adaptive seasonality in more detail in three northern forest ecoprovinces. In the Northern and Middle Rockies, areas of adaptive seasonality decreased at lower elevations and increased at higher elevations during warmer periods, resulting in a movement upward in elevation of adaptive seasonality. In contrast, the Cascade Mountains exhibited overall declines in adaptive seasonality with higher temperatures regardless of elevation. Projections of future warming (5°C in the western United States) resulted in substantial reductions in the

  14. Target-specific PCR primers can detect and differentiate ophiostomatoid fungi from microbial communities associated with the mountain pine beetle Dendroctonus ponderosae.

    PubMed

    Khadempour, Lily; Massoumi Alamouti, Sepideh; Hamelin, Richard; Bohlmann, Jörg; Breuil, Colette

    2010-10-01

    The aim of this study was to develop DNA probes that could identify the major fungal species associated with mountain pine beetles (MPB). The beetles are closely associated with fungal species that include ophiostomatoid fungi that can be difficult to differentiate morphologically. The most frequently isolated associates are the pine pathogens Grosmannia clavigera and Leptographium longiclavatum, the less pathogenic Ophiostoma montium, and an undescribed Ceratocystiopsis species (Cop. sp.). Because growing, isolating and extracting DNA from fungi vectored by MPB can be time and labour intensive, we designed three rDNA primer sets that specifically amplify short rDNA amplicons from O. montium, Cop. sp. and the pine Leptographium clade. We also designed two primer sets on a gene of unknown function that can differentiate G. clavigera and L. longiclavatum. We tested the primers on 76 fungal isolates that included MPB associates. The primers reliably identified their targets from DNA obtained from pure fungal cultures, pulverized beetles, beetle galleries, and tree phloem inoculated with G. clavigera. The primers will facilitate large-scale work on the ecology of the MPB-fungal-lodgepole pine ecosystem, as well as phytosanitary/quarantine sample screening.

  15. Leptographium wingfieldii introduced into North America and found associated with exotic Tomicus piniperda and native bark beetles.

    PubMed

    Jacobs, Karin; Bergdahl, Dale R; Wingfield, Michael J; Halik, Shari; Seifert, Keith A; Bright, Donald E; Wingfield, Brenda D

    2004-04-01

    Leptographium wingfieldii is a well-known fungal associate of the pine shoot beetle, Tomicus piniperda, in Europe. This fungus is pathogenic to pines and is an important cause of blue-stain in the sapwood of infested trees. Tomicus piniperda was first found in a Christmas tree plantation in Ohio, USA, 1992, but isolation of the fungi associated with these intercepted insects was not attempted. Fungal strains resembling L. wingfieldii were recently isolated from pines attacked by T. piniperda, Dendroctonus valens and Ips pini in the northeastern United States. These strains were morphologically similar to the ex-type and other reference strains of L. wingfieldii. Strains were also compared based on sequences of the partial ITS ribosomal DNA operon, beta-tubulin and elongation factor 1-alpha (EF-1alpha) genes. Based on these DNA sequence comparisons, reference strains of European L. wingfieldii were conspecific with North American strains from pines attacked by T. piniperda, D. valens and I. pini. A single strain from Canada, collected in 1993 near the Ontario border with the USA, shortly after the discovery of T. piniperda in that area and tentatively identified as L. wingfieldii, was also included in this study. Its identification was confirmed, suggesting that L. wingfieldii has been present in this region and probably over the whole range of the insect's distribution for at least a decade. This represents the first record of L. wingfieldii associated with the introduced and damaging pine shoot beetle T. piniperda in North America. It shows that the fungus is well established and can become associated with other native bark beetles that attack stressed and/or dying trees. The occurrence and spread of this highly pathogenic fungus associated with North American bark beetles should be monitored. PMID:15209281

  16. Leptographium wingfieldii introduced into North America and found associated with exotic Tomicus piniperda and native bark beetles.

    PubMed

    Jacobs, Karin; Bergdahl, Dale R; Wingfield, Michael J; Halik, Shari; Seifert, Keith A; Bright, Donald E; Wingfield, Brenda D

    2004-04-01

    Leptographium wingfieldii is a well-known fungal associate of the pine shoot beetle, Tomicus piniperda, in Europe. This fungus is pathogenic to pines and is an important cause of blue-stain in the sapwood of infested trees. Tomicus piniperda was first found in a Christmas tree plantation in Ohio, USA, 1992, but isolation of the fungi associated with these intercepted insects was not attempted. Fungal strains resembling L. wingfieldii were recently isolated from pines attacked by T. piniperda, Dendroctonus valens and Ips pini in the northeastern United States. These strains were morphologically similar to the ex-type and other reference strains of L. wingfieldii. Strains were also compared based on sequences of the partial ITS ribosomal DNA operon, beta-tubulin and elongation factor 1-alpha (EF-1alpha) genes. Based on these DNA sequence comparisons, reference strains of European L. wingfieldii were conspecific with North American strains from pines attacked by T. piniperda, D. valens and I. pini. A single strain from Canada, collected in 1993 near the Ontario border with the USA, shortly after the discovery of T. piniperda in that area and tentatively identified as L. wingfieldii, was also included in this study. Its identification was confirmed, suggesting that L. wingfieldii has been present in this region and probably over the whole range of the insect's distribution for at least a decade. This represents the first record of L. wingfieldii associated with the introduced and damaging pine shoot beetle T. piniperda in North America. It shows that the fungus is well established and can become associated with other native bark beetles that attack stressed and/or dying trees. The occurrence and spread of this highly pathogenic fungus associated with North American bark beetles should be monitored.

  17. Incorporating Carbon Storage into the Optimal Management of Forest Insect Pests: A Case Study of the Southern Pine Beetle ( Dendroctonus Frontalis Zimmerman) in the New Jersey Pinelands

    NASA Astrophysics Data System (ADS)

    Niemiec, Rebecca M.; Lutz, David A.; Howarth, Richard B.

    2014-10-01

    Forest insect pest disturbance is increasing in certain areas of North America as many insect species, such as the southern pine beetle, expand their range due to a warming climate. Because insect pests are beginning to occupy forests that are managed for multiple uses and have not been managed for pests before, it is becoming increasingly important to determine how forests should be managed for pests when non-timber ecosystem services are considered in addition to traditional costs and revenues. One example of a service that is increasingly considered in forest management and that may affect forest pest management is carbon sequestration. This manuscript seeks to understand whether the incorporation of forest carbon sequestration into cost-benefit analysis of different forest pest management strategies affects the financially optimal strategy. We examine this question through a case study of the southern pine beetle (SPB) in a new area of SPB expansion, the New Jersey Pinelands National Reserve (NJPR). We utilize a forest ecology and economics model and include field data from the NJPR as well as outbreak probability statistics from previous years. We find under the majority of scenarios, incorporating forest carbon sequestration shifts the financially optimal SPB management strategy from preventative thinning toward no management or reactionary management in forest stands in New Jersey. These results contradict the current recommended treatment strategy for SPB and signify that the inclusion of multiple ecosystem services into a cost-benefit analysis may drastically alter which pest management strategy is economically optimal.

  18. What is the password? Female bark beetles (Scolytinae) grant males access to their galleries based on courtship song.

    PubMed

    Lindeman, Amanda A; Yack, Jayne E

    2015-06-01

    Acoustic signals are commonly used by insects in the context of mating, and signals can vary depending on the stage of interaction between a male and female. While calling songs have been studied extensively, particularly in the Orthoptera, much less is known about courtship songs. One outstanding question is how potential mates are differentiated by their courtship signal characteristics. We examined acoustic courtship signals in a new system, bark beetles (Scolytinae). In the red turpentine beetle (Dendroctonus valens) males produce chirp trains upon approaching the entrance of a female's gallery. We tested the hypotheses that acoustic signals are honest indicators of male condition and that females choose males based on signal characteristics. Males generated two distinct chirp types (simple and interrupted), and variability in their prevalence correlated with an indicator of male quality, body size, with larger males producing significantly more interrupted chirps. Females showed a significant preference for males who produced interrupted chirps, suggesting that females distinguish between males on the basis of their chirp performances. We suggest that interrupted chirps during courtship advertise a male's size and/or motor skills, and function as the proverbial 'passwords' that allow him entry to a female's gallery. PMID:25783802

  19. Pulpability of beetle-killed spruce. Forest Service research paper

    SciTech Connect

    Scott, G.M.; Bormett, D.W.; Sutherland, N.R.; Abubakr, S.; Lowell, E.

    1996-08-01

    Infestation of the Dendroctonus rufipennis beetle has resulted in large stands of dead and dying timber on the Kenai Peninsula in Alaska. Tests were conducted to evaluate the value of beetle-killed spruce as pulpwood. The results showed that live and dead spruce wood can be pulped effectively. The two least deteriorated classes and the most deteriorated class of logs had similar characteristics when pulped; the remaining class had somewhat poorer pulpability.

  20. Pheromone production by axenically rearedDendroctonus ponderosae andIps paraconfusus (Coleoptera: Scolytidae).

    PubMed

    Conn, J E; Borden, J H; Hunt, D W; Holman, J; Whitney, H S; Spanier, O J; Pierce, H D; Oehlschlager, A C

    1984-02-01

    Mountain pine beetles,Dendroctonus ponderosae Hopkins, and California five-spined ips,Ips paraconfusus Lanier, were reared axenically from surface-sterilized eggs on aseptic pine phloem. After 24 hr in host logs, axenip femaleD. ponderosae and maleI. paraconfusus produced the aggregation pheromones,trans-verbenol (D. ponderosae), and ipsenol and ipsdienol (I. paraconfusus). Emergent, axenically reared maleD. ponderosae contained normal amounts of the pheromoneexo-brevicomin. Axenic femaleD. ponderosae treated with juvenile hormone or exposed to vapors of α-pinene, produced the pheromonetrans-verbenol. By 25-35 days after eclosion, axenic females exposed to α-pinene vapors produced over six times as muchtrans-verbenol as wild females, suggesting that while microorganisms in wild females may producetrans-verbenol, they may also inhibit production of the pheromone or use it as a substrate.

  1. White Spruce Regeneration Following a Major Spruce Beetle Outbreak in Forests on the Kenai Peninsula, Alaska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Between 1987 and 2000, a spruce beetle (Dendroctonus rufipennis) epidemic infested 1.19 million hectares of spruce (Picea spp.) forests in Alaska, killing most of the large diameter trees. We evaluated whether these forests would recover to their pre-outbreak density, and determined the site conditi...

  2. Chemical ecology of bark beetles in regard to search and selection of host trees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bark beetles (Coleoptera: Scolytidae), especially pests in the genera Dendroctonus, Ips, Scolytus, Trypodendron, Tomicus, and Pityogenes of the Northern hemisphere are reviewed regarding aspects of their chemical ecology during host finding and selection. Most of the species covered here feed on con...

  3. Seasonal Phenology and Life-History of Dendroctonus simplex (Coleoptera: Curculionidae) in the Great Lakes Region of North America.

    PubMed

    McKee, Fraser R; Aukema, Brian H

    2016-08-01

    The eastern larch beetle, Dendroctonus simplex LeConte (Coleoptera: Curculionidae), is distributed throughout the North American boreal forest sympatric with its primary host, the eastern larch or tamarack, Larix laricina (Du Roi) K. Koch. Outbreaks of eastern larch beetles are typically small and associated with stressed tamaracks. Since 2000, however, an outbreak has killed >90,000 ha of tamarack in Minnesota and surrounding Great Lakes region. Identifying the causes of this epidemic is challenging due to knowledge gaps regarding the insect's biology. We present field data from 2011 to 2014 on degree days associated with spring emergence, dispersal, host colonization, and re-emergence from colonized hosts by mature adult beetles, as well as degree days associated with larval development, and prewinter emergence by adult progeny at study sites in northern Minnesota. After initial host colonization in early spring we found that a second brood was established in early summer by re-emerging parents. In 2012, a third brood was established. Across study years, first broods developed to adults by late summer, with many beetles relocating to the base of the host tree to overwinter. Second broods often reached adulthood and initiated prewinter emergence. The third brood of 2012 overwintered as adults, pupae, and late-instars, resuming development the following spring. Each spring, emergence of adult beetles from all broods established the previous year was highly synchronous. Knowledge of the biology of eastern larch beetles along the southern margin of their range aids in understanding how population dynamics may change with a changing climate. PMID:27333874

  4. Seasonal Phenology and Life-History of Dendroctonus simplex (Coleoptera: Curculionidae) in the Great Lakes Region of North America.

    PubMed

    McKee, Fraser R; Aukema, Brian H

    2016-08-01

    The eastern larch beetle, Dendroctonus simplex LeConte (Coleoptera: Curculionidae), is distributed throughout the North American boreal forest sympatric with its primary host, the eastern larch or tamarack, Larix laricina (Du Roi) K. Koch. Outbreaks of eastern larch beetles are typically small and associated with stressed tamaracks. Since 2000, however, an outbreak has killed >90,000 ha of tamarack in Minnesota and surrounding Great Lakes region. Identifying the causes of this epidemic is challenging due to knowledge gaps regarding the insect's biology. We present field data from 2011 to 2014 on degree days associated with spring emergence, dispersal, host colonization, and re-emergence from colonized hosts by mature adult beetles, as well as degree days associated with larval development, and prewinter emergence by adult progeny at study sites in northern Minnesota. After initial host colonization in early spring we found that a second brood was established in early summer by re-emerging parents. In 2012, a third brood was established. Across study years, first broods developed to adults by late summer, with many beetles relocating to the base of the host tree to overwinter. Second broods often reached adulthood and initiated prewinter emergence. The third brood of 2012 overwintered as adults, pupae, and late-instars, resuming development the following spring. Each spring, emergence of adult beetles from all broods established the previous year was highly synchronous. Knowledge of the biology of eastern larch beetles along the southern margin of their range aids in understanding how population dynamics may change with a changing climate.

  5. Localized spatial and temporal attack dynamics of the mountain pine beetle in lodgepole pine. Forest Service research paper

    SciTech Connect

    Bentz, B.J.; Powell, J.A.; Logan, J.A.

    1996-12-01

    Colonization of a host tree by the mountain pine beetle (Dendroctonus ponderosae) involves chemical communication that enables a massive aggregation of beetles on a single resource, thereby ensuring host death and subsequent beetle population survival. Beetle populations have evolved a mechanism for termination of colonization on a lodgepole pine tree at optimal beetle densities, with a concomitant switch of attacks to nearby trees. Observations of the daily spatial and temporal attack process of mountain pine beetles (nonepidemic) attacking lodgepole pine suggest that beetles switch attacks to a new host tree before the original focus tree is fully colonized, and that verbenone, an antiaggregating pheromone, may be acting within a tree rather than between trees.

  6. Recent mountain pine beetle outbreaks, wildfire severity, and postfire tree regeneration in the US Northern Rockies.

    PubMed

    Harvey, Brian J; Donato, Daniel C; Turner, Monica G

    2014-10-21

    Widespread tree mortality caused by outbreaks of native bark beetles (Circulionidae: Scolytinae) in recent decades has raised concern among scientists and forest managers about whether beetle outbreaks fuel more ecologically severe forest fires and impair postfire resilience. To investigate this question, we collected extensive field data following multiple fires that burned subalpine forests in 2011 throughout the Northern Rocky Mountains across a spectrum of prefire beetle outbreak severity, primarily from mountain pine beetle (Dendroctonus ponderosae). We found that recent (2001-2010) beetle outbreak severity was unrelated to most field measures of subsequent fire severity, which was instead driven primarily by extreme burning conditions (weather) and topography. In the red stage (0-2 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity with few effects detected only under extreme burning conditions. In the gray stage (3-10 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity under moderate conditions, but several measures related to surface fire severity increased with outbreak severity under extreme conditions. Initial postfire tree regeneration of the primary beetle host tree [lodgepole pine (Pinus contorta var. latifolia)] was not directly affected by prefire outbreak severity but was instead driven by the presence of a canopy seedbank and by fire severity. Recent beetle outbreaks in subalpine forests affected few measures of wildfire severity and did not hinder the ability of lodgepole pine forests to regenerate after fire, suggesting that resilience in subalpine forests is not necessarily impaired by recent mountain pine beetle outbreaks.

  7. Factors influencing flight capacity of the mountain pine beetle (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Evenden, M L; Whitehouse, C M; Sykes, J

    2014-02-01

    The mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae) is the most damaging pest of mature pine (Pinaceae) in western North America. Although mountain pine beetles have an obligate dispersal phase during which adults must locate a new host for brood production, dispersal is a poorly understood aspect of its ecology. This flight mill study was designed to test the effects of beetle size, sex, and age on flight capacity. Energy use during flight was assessed through measurements of weight before and after flight and fat content of flown versus control beetles. The mean flight distance achieved by mountain pine beetles varied between 2.12 and 5.95 km over the 23-h bioassay, but the longest total flight of an individual beetle was >24 km. Beetle preflight weight influenced flight initiation, flight distance, and duration. Bigger beetles are more likely to fly and once in flight fly longer and farther than smaller beetles. There was no direct effect of beetle sex on flight capacity. Flight capacity of beetles declined with age postemergence. Although individual flight capacity was variable, flight velocity was relatively constant between 1.55 and 1.93 km/h. Lipids are used to power flight in mountain pine beetles, as lipid content was lower in beetles flown on the flight mills compared with beetles that did not fly. Flight distance was negatively correlated with beetle postflight lipid content. The baseline flight capacity data revealed in this study have implications for understanding the population dynamics of this eruptive forest pest.

  8. A General Class of Test Statistics for Van Valen's Red Queen Hypothesis.

    PubMed

    Wiltshire, Jelani; Huffer, Fred W; Parker, William C

    2014-09-01

    Van Valen's Red Queen hypothesis states that within a homogeneous taxonomic group the age is statistically independent of the rate of extinction. The case of the Red Queen hypothesis being addressed here is when the homogeneous taxonomic group is a group of similar species. Since Van Valen's work, various statistical approaches have been used to address the relationship between taxon age and the rate of extinction. We propose a general class of test statistics that can be used to test for the effect of age on the rate of extinction. These test statistics allow for a varying background rate of extinction and attempt to remove the effects of other covariates when assessing the effect of age on extinction. No model is assumed for the covariate effects. Instead we control for covariate effects by pairing or grouping together similar species. Simulations are used to compare the power of the statistics. We apply the test statistics to data on Foram extinctions and find that age has a positive effect on the rate of extinction. A derivation of the null distribution of one of the test statistics is provided in the supplementary material.

  9. What is Next in Bark Beetle Phylogeography?

    PubMed Central

    Avtzis, Dimitrios N.; Bertheau, Coralie; Stauffer, Christian

    2012-01-01

    Bark beetle species within the scolytid genera Dendroctonus, Ips, Pityogenes and Tomicus are known to cause extensive ecological and economical damage in spruce and pine forests during epidemic outbreaks all around the world. Dendroctonus ponderosae poses the most recent example having destroyed almost 100,000 km2 of conifer forests in North America. The success and effectiveness of scolytid species lies mostly in strategies developed over the course of time. Among these, a complex system of semiochemicals promotes the communication and aggregation on the spot of infestation facilitating an en masse attack against a host tree’s defenses; or an association with fungi that evolved either in the form of nutrition (ambrosia fungi) or even by reducing the resistance of host trees (blue-stain fungi). Although often specific to a tree genus or species, some bark beetles are polyphagous and have the ability to switch on to new hosts and extend their host range (i.e., between conifer genera such as Pityogenes chalcographus or even from conifer to deciduous trees as Polygraphus grandiclava). A combination of these capabilities in concert with life history or ecological traits explains why bark beetles are considered interesting subjects in evolutionary studies. Several bark beetle species appear in phylogeographic investigations, in an effort to improve our understanding of their ecology, epidemiology and evolution. In this paper investigations that unveil the phylogeographic history of bark beetles are reviewed. A close association between refugial areas and postglacial migration routes that insects and host trees have followed in the last 15,000 BP has been suggested in many studies. Finally, a future perspective of how next generation sequencing will influence the resolution of phylogeographic patterns in the coming years is presented. Utilization of such novel techniques will provide a more detailed insight into the genome of scolytids facilitating at the same time the

  10. What is Next in Bark Beetle Phylogeography?

    PubMed

    Avtzis, Dimitrios N; Bertheau, Coralie; Stauffer, Christian

    2012-05-07

    Bark beetle species within the scolytid genera Dendroctonus, Ips, Pityogenes and Tomicus are known to cause extensive ecological and economical damage in spruce and pine forests during epidemic outbreaks all around the world. Dendroctonus ponderosae poses the most recent example having destroyed almost 100,000 km² of conifer forests in North America. The success and effectiveness of scolytid species lies mostly in strategies developed over the course of time. Among these, a complex system of semiochemicals promotes the communication and aggregation on the spot of infestation facilitating an en masse attack against a host tree's defenses; or an association with fungi that evolved either in the form of nutrition (ambrosia fungi) or even by reducing the resistance of host trees (blue-stain fungi). Although often specific to a tree genus or species, some bark beetles are polyphagous and have the ability to switch on to new hosts and extend their host range (i.e., between conifer genera such as Pityogenes chalcographus or even from conifer to deciduous trees as Polygraphus grandiclava). A combination of these capabilities in concert with life history or ecological traits explains why bark beetles are considered interesting subjects in evolutionary studies. Several bark beetle species appear in phylogeographic investigations, in an effort to improve our understanding of their ecology, epidemiology and evolution. In this paper investigations that unveil the phylogeographic history of bark beetles are reviewed. A close association between refugial areas and postglacial migration routes that insects and host trees have followed in the last 15,000 BP has been suggested in many studies. Finally, a future perspective of how next generation sequencing will influence the resolution of phylogeographic patterns in the coming years is presented. Utilization of such novel techniques will provide a more detailed insight into the genome of scolytids facilitating at the same time the

  11. Temporal variation in mycophagy and prevalence of fungi associated with developmental stages of Dendroctonus ponderosae (Coleoptera: Curculionidae).

    PubMed

    Adams, Aaron S; Six, Diana L

    2007-02-01

    Mycophagy by bark beetles is widespread. However, little is known regarding which developmental stages of bark beetles actually feed on fungi. To study this question, we sampled fungi associated with Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae) throughout development in naturally attacked trees. Isolations of fungi were made from phloem adjacent to brood and from brood exoskeletons and guts. Overall, the incidence of fungi with individual brood increased as brood development progressed. Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer and Wingf. and Ophiostoma montium (Rumbold) von Arx exhibited generally opposing trends in prevalence. G. clavigera was most likely to be found in phloem adjacent to prewintering third- and postwintering fourth-instar larvae. O. montium was most likely to be found in phloem adjacent to eggs, first-instar larvae, pupae, and teneral adults. In contrast to isolations made from phloem, fungi isolated from brood guts and exoskeletons were not observed to shift in prevalence. First- and third-instar larvae were often observed migrating to older portions of their galleries, indicating that they do not spend all of their time feeding at, and extending, the apex of the gallery. Our results suggest that not only are D. ponderosae brood in contact with and feeding on fungi throughout development, but also, that during development, contact of brood with a particular fungus is likely to change. Such temporal shifts in fungal symbionts may be environmentally driven and have important implications in how these fungi interact with their hosts within and across generations.

  12. Using pheromones to protect heat-injured lodgepole pine from mountain pine beetle infestation. Forest Service research note

    SciTech Connect

    Amman, G.D.; Ryan, K.C.

    1994-01-01

    The bark beetle antiaggregative pheromones, verbenone and ipsdienol, were tested in protecting heat-injured lodgepole pine (Pinus contorta Dougl. ex Loud.) from mountain pine beetle (Dendroctonus ponderosae) infestation in the Sawtooth National Recreation Area in central Idaho. Peat moss was placed around 70 percent of the basal circumference of lodgepole pines. When the peat moss was ignited, it simulated the smoldering of natural duff, generating temperatures that killed the cambium. The four treatments tested were uninjured tree, heat-injured tree, heat-injured tree treated with verbenone, and heat-injured tree treated with verbenone plus ipsdienol. Treatments were replicated 20 times. Mountain pine beetles were attracted into treatment blocks by placing mountain pine beetle tree baits on metal posts 3 to 5 meters from treated trees. Fisher's Extract Test showed that treatment and beetle infestation were not independent (P < 0.015). Check treatments contained more unattacked and mass-attacked trees, whereas pheromone treatments contained more unsuccessfully attacked trees.

  13. Mountain pine beetle infestation impacted by water availability

    NASA Astrophysics Data System (ADS)

    Kaiser, K. E.; McGlynn, B.; Emanuel, R.

    2012-04-01

    Vegetation pattern and landscape structure intersect to exert strong control over ecohydrological dynamics at the watershed scale. The hydrologic implications of vegetation disturbance (e.g. fire, disease etc.) depend on the spatial pattern and form of environmental change. Here we investigate this intersection at Tenderfoot Creek Experimental Forest (TCEF), Montana with a focus on the mountain pine beetle (Dendroctonus ponderosae) epidemic currently affecting the Rocky Mountains. We calibrated QuickBird remote sensing imagery with a leaf-level spectral library of local vegetation. We used this spectral library to determine optimal vegetation indices for differentiating stages of beetle infestation within the 37 km2 TCEF watershed. These indices formed the basis of a three-component mixing model to quantify the extent and magnitude of beetle infestation across the TCEF watershed. We compared disturbance patterns to spatially distributed topography and vegetation variables derived from a LiDAR-based digital elevation model (DEM) of TCEF. We determined that certain landscape characteristics (low vegetation density, south facing slopes, steep slopes, locations with small contributing areas, and locations with lower values of the topographic wetness index (TWI)) were significantly more likely to exhibit the effects of beetle infestation. Our efforts to monitor vegetation mortality across space and time provide a context for assessing landscape susceptibility to initial mountain pine beetle infestation via feedbacks between biodiversity and hydrological patterns and further research into understanding how outbreak (i.e. landscape scale infestation) patterns may affect watershed ecohydrology via altered water and biogeochemical cycles.

  14. Fire severity unaffected by spruce beetle outbreak in spruce-fir forests in southwestern Colorado.

    PubMed

    Andrus, Robert A; Veblen, Thomas T; Harvey, Brian J; Hart, Sarah J

    2016-04-01

    Recent large and severe outbreaks of native bark beetles have raised concern among the general public and land managers about potential for amplified fire activity in western North America. To date, the majority of studies examining bark beetle outbreaks and subsequent fire severity in the U.S. Rocky Mountains have focused on outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests, but few studies, particularly field studies, have addressed the effects of the severity of spruce beetle (Dendroctonus rufipennis Kirby) infestation on subsequent fire severity in subalpine Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests. In Colorado, the annual area infested by spruce beetle outbreaks is rapidly rising, while MPB outbreaks are subsiding; therefore understanding this relationship is of growing importance. We collected extensive field data in subalpine forests in the eastern San Juan Mountains, southwestern Colorado, USA, to investigate whether a gray-stage (< 5 yr from outbreak to time of fire) spruce beetle infestation affected fire severity. Contrary to the expectation that bark beetle infestation alters subsequent fire severity, correlation and multivariate generalized linear regression analysis revealed no influence of pre-fire spruce beetle severity on nearly all field or remotely sensed measurements of fire severity. Findings were consistent across moderate and extreme burning conditions. In comparison to severity of the pre-fire beetle outbreak, we found that topography, pre-outbreak basal area, and weather conditions exerted a stronger effect on fire severity. Our finding that beetle infestation did not alter fire severity is consistent with previous retrospective studies examining fire activity following other bark beetle outbreaks and reiterates the overriding influence of climate that creates conditions conducive to large, high-severity fires in the subalpine zone of Colorado

  15. Fire severity unaffected by spruce beetle outbreak in spruce-fir forests in southwestern Colorado.

    PubMed

    Andrus, Robert A; Veblen, Thomas T; Harvey, Brian J; Hart, Sarah J

    2016-04-01

    Recent large and severe outbreaks of native bark beetles have raised concern among the general public and land managers about potential for amplified fire activity in western North America. To date, the majority of studies examining bark beetle outbreaks and subsequent fire severity in the U.S. Rocky Mountains have focused on outbreaks of mountain pine beetle (MPB; Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests, but few studies, particularly field studies, have addressed the effects of the severity of spruce beetle (Dendroctonus rufipennis Kirby) infestation on subsequent fire severity in subalpine Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) forests. In Colorado, the annual area infested by spruce beetle outbreaks is rapidly rising, while MPB outbreaks are subsiding; therefore understanding this relationship is of growing importance. We collected extensive field data in subalpine forests in the eastern San Juan Mountains, southwestern Colorado, USA, to investigate whether a gray-stage (< 5 yr from outbreak to time of fire) spruce beetle infestation affected fire severity. Contrary to the expectation that bark beetle infestation alters subsequent fire severity, correlation and multivariate generalized linear regression analysis revealed no influence of pre-fire spruce beetle severity on nearly all field or remotely sensed measurements of fire severity. Findings were consistent across moderate and extreme burning conditions. In comparison to severity of the pre-fire beetle outbreak, we found that topography, pre-outbreak basal area, and weather conditions exerted a stronger effect on fire severity. Our finding that beetle infestation did not alter fire severity is consistent with previous retrospective studies examining fire activity following other bark beetle outbreaks and reiterates the overriding influence of climate that creates conditions conducive to large, high-severity fires in the subalpine zone of Colorado

  16. The ecology of yeasts in the bark beetle holobiont: a century of research revisited.

    PubMed

    Davis, Thomas Seth

    2015-05-01

    Yeasts are extremely common associates of scolytine bark beetles, yet the basic ecology of yeasts in the bark beetle holobiont remains poorly understood. Yeasts are present in all beetle life stages and consistently isolated from adult, larval, and pupal integuments and mycangial structures, but yeasts are also found in oviposition galleries, pupal chambers, larval and adult digestive tracts, as well as phloem and xylem tissues. Yeasts in the Saccharomycetaceae family are the most prevalent associates, and most individual beetles are associated with only one or several yeast species. Kuraishia capsulata and Ogataea pini are the most commonly encountered yeast species in surveys of Dendroctonus and Ips beetles; most beetles that have been surveyed are vectors for one or both yeasts. Yeasts have significant but often overlooked functional roles in bark beetle ecology. Infochemicals resulting from volatile production by yeast have wide-ranging bioactivity for arthropods: Yeast emissions attract beetles at low concentrations but repel beetles at high concentrations, and yeast emissions can also serve as cues to predators and parasites of bark beetles. In some cases, yeasts can modify tree chemistry over time or metabolize toxic terpenoids, though potential consequences for beetle performance or the growth of nutritional fungi remain to be demonstrated. Also, the presence of yeast species can restrict or promote the establishment and growth of filamentous fungi, including mutualists, entomopathogens, and opportunistic saprophytes. The role of yeasts as nutritional symbionts has received mixed support, though a nutritional hypothesis has not been extensively tested. Continued research on the functional ecology of bark beetle-yeast associations is needed to better understand the emergent properties of these complex symbiont assemblages.

  17. Negative Feedbacks on Bark Beetle Outbreaks: Widespread and Severe Spruce Beetle Infestation Restricts Subsequent Infestation

    PubMed Central

    Hart, Sarah J.; Veblen, Thomas T.; Mietkiewicz, Nathan; Kulakowski, Dominik

    2015-01-01

    Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced a severe landscape-scale spruce beetle infestation in the 1940s. We hypothesized that drought and warm temperatures would promote infestation, whereas small diameter and non-host trees, which may reflect past disturbance by spruce beetles, would inhibit infestation. Across the Southern Rocky Mountains, we found that climate and forest structure interacted to drive the 2000s infestation. Within the Flat Tops study area we found that stands infested in the 1940s were composed of higher proportions of small diameter and non-host trees ca. 60 years later. In this area, the 2000s infestation was constrained by a paucity of large diameter host trees (> 23 cm at diameter breast height), not climate. This suggests that there has not been sufficient time for trees to grow large enough to become susceptible to infestation. Concordantly, we found no overlap between areas affected by the 1940s infestation and the current infestation. These results show a severe spruce beetle infestation, which results in the depletion of susceptible hosts, can create a landscape template reducing the potential for future infestations. PMID:26000906

  18. Negative feedbacks on bark beetle outbreaks: widespread and severe spruce beetle infestation restricts subsequent infestation.

    PubMed

    Hart, Sarah J; Veblen, Thomas T; Mietkiewicz, Nathan; Kulakowski, Dominik

    2015-01-01

    Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced a severe landscape-scale spruce beetle infestation in the 1940s. We hypothesized that drought and warm temperatures would promote infestation, whereas small diameter and non-host trees, which may reflect past disturbance by spruce beetles, would inhibit infestation. Across the Southern Rocky Mountains, we found that climate and forest structure interacted to drive the 2000s infestation. Within the Flat Tops study area we found that stands infested in the 1940s were composed of higher proportions of small diameter and non-host trees ca. 60 years later. In this area, the 2000s infestation was constrained by a paucity of large diameter host trees (> 23 cm at diameter breast height), not climate. This suggests that there has not been sufficient time for trees to grow large enough to become susceptible to infestation. Concordantly, we found no overlap between areas affected by the 1940s infestation and the current infestation. These results show a severe spruce beetle infestation, which results in the depletion of susceptible hosts, can create a landscape template reducing the potential for future infestations.

  19. Negative feedbacks on bark beetle outbreaks: widespread and severe spruce beetle infestation restricts subsequent infestation.

    PubMed

    Hart, Sarah J; Veblen, Thomas T; Mietkiewicz, Nathan; Kulakowski, Dominik

    2015-01-01

    Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced a severe landscape-scale spruce beetle infestation in the 1940s. We hypothesized that drought and warm temperatures would promote infestation, whereas small diameter and non-host trees, which may reflect past disturbance by spruce beetles, would inhibit infestation. Across the Southern Rocky Mountains, we found that climate and forest structure interacted to drive the 2000s infestation. Within the Flat Tops study area we found that stands infested in the 1940s were composed of higher proportions of small diameter and non-host trees ca. 60 years later. In this area, the 2000s infestation was constrained by a paucity of large diameter host trees (> 23 cm at diameter breast height), not climate. This suggests that there has not been sufficient time for trees to grow large enough to become susceptible to infestation. Concordantly, we found no overlap between areas affected by the 1940s infestation and the current infestation. These results show a severe spruce beetle infestation, which results in the depletion of susceptible hosts, can create a landscape template reducing the potential for future infestations. PMID:26000906

  20. Polygamy and an absence of fine-scale structure in Dendroctonus ponderosae (Hopk.) (Coleoptera: Curcilionidae) confirmed using molecular markers.

    PubMed

    Janes, J K; Roe, A D; Rice, A V; Gorrell, J C; Coltman, D W; Langor, D W; Sperling, F A H

    2016-01-01

    An understanding of mating systems and fine-scale spatial genetic structure is required to effectively manage forest pest species such as Dendroctonus ponderosae (mountain pine beetle). Here we used genome-wide single-nucleotide polymorphisms to assess the fine-scale genetic structure and mating system of D. ponderosae collected from a single stand in Alberta, Canada. Fine-scale spatial genetic structure was absent within the stand and the majority of genetic variation was best explained at the individual level. Relatedness estimates support previous reports of pre-emergence mating. Parentage assignment tests indicate that a polygamous mating system better explains the relationships among individuals within a gallery than the previously reported female monogamous/male polygynous system. Furthermore, there is some evidence to suggest that females may exploit the galleries of other females, at least under epidemic conditions. Our results suggest that current management models are likely to be effective across large geographic areas based on the absence of fine-scale genetic structure.

  1. Polygamy and an absence of fine-scale structure in Dendroctonus ponderosae (Hopk.) (Coleoptera: Curcilionidae) confirmed using molecular markers

    PubMed Central

    Janes, J K; Roe, A D; Rice, A V; Gorrell, J C; Coltman, D W; Langor, D W; Sperling, F A H

    2016-01-01

    An understanding of mating systems and fine-scale spatial genetic structure is required to effectively manage forest pest species such as Dendroctonus ponderosae (mountain pine beetle). Here we used genome-wide single-nucleotide polymorphisms to assess the fine-scale genetic structure and mating system of D. ponderosae collected from a single stand in Alberta, Canada. Fine-scale spatial genetic structure was absent within the stand and the majority of genetic variation was best explained at the individual level. Relatedness estimates support previous reports of pre-emergence mating. Parentage assignment tests indicate that a polygamous mating system better explains the relationships among individuals within a gallery than the previously reported female monogamous/male polygynous system. Furthermore, there is some evidence to suggest that females may exploit the galleries of other females, at least under epidemic conditions. Our results suggest that current management models are likely to be effective across large geographic areas based on the absence of fine-scale genetic structure. PMID:26286666

  2. The impact of phloem nutrients on overwintering mountain pine beetles and their fungal symbionts.

    PubMed

    Goodsman, Devin W; Erbilgin, Nadir; Lieffers, Victor J

    2012-06-01

    In the low nutrient environment of conifer bark, subcortical beetles often carry symbiotic fungi that concentrate nutrients in host tissues. Although bark beetles are known to benefit from these symbioses, whether this is because they survive better in nutrient-rich phloem is unknown. After manipulating phloem nutrition by fertilizing lodgepole pine trees (Pinus contorta Douglas var. latifolia), we found bolts from fertilized trees to contain more living individuals, and especially more pupae and teneral adults than bolts from unfertilized trees at our southern site. At our northern site, we found that a larger proportion of mountain pine beetle (Dendroctonus ponderosae Hopkins) larvae built pupal chambers in bolts from fertilized trees than in bolts from unfertilized trees. The symbiotic fungi of the mountain pine beetle also responded to fertilization. Two mutualistic fungi of bark beetles, Grosmannia clavigera (Rob.-Jeffr. & R. W. Davidson) Zipfel, Z. W. de Beer, & M. J. Wingf. and Leptographium longiclavatum Lee, S., J. J. Kim, & C. Breuil, doubled the nitrogen concentrations near the point of infection in the phloem of fertilized trees. These fungi were less capable of concentrating nitrogen in unfertilized trees. Thus, the fungal symbionts of mountain pine beetle enhance phloem nutrition and likely mediate the beneficial effects of fertilization on the survival and development of mountain pine beetle larvae. PMID:22732605

  3. Comparison of naturally and synthetically baited spruce beetle trapping systems in the central Rocky Mountains.

    PubMed

    Hansen, E M; Vandygriff, J C; Cain, R J; Wakarchuk, D

    2006-04-01

    We compared naturally baited trapping systems to synthetically baited funnel traps and fallen trap trees for suppressing preoutbreak spruce beetle, Dendroctonus rufipennis Kirby, populations. Lures for the traps were fresh spruce (Picea spp.) bolts or bark sections, augmented by adding female spruce beetles to create secondary attraction. In 2003, we compared a naturally baited system ("bolt trap") with fallen trap trees and with synthetically baited funnel traps. Trap performance was evaluated by comparing total beetle captures and spillover of attacks into nearby host trees. Overall, the trap systems did not significantly differ in spruce beetle captures, although bolt traps caught 6 to 7 times more beetles than funnel traps during the first 4 wk of testing. Funnel traps with synthetic lures had significantly more spillover than either trap trees or bolt traps. The study was repeated in 2004 with modifications including an enhanced blend synthetic lure. Again, trap captures were generally similar among naturally and synthetically baited traps, but naturally baited traps had significantly less spillover. Although relatively labor-intensive, the bolt trap could be used to suppress preoutbreak beetle populations, especially when spillover is undesirable. Our work provides additional avenues for management of spruce beetles and suggests that currently used synthetic lures can be improved. PMID:16686135

  4. The impact of phloem nutrients on overwintering mountain pine beetles and their fungal symbionts.

    PubMed

    Goodsman, Devin W; Erbilgin, Nadir; Lieffers, Victor J

    2012-06-01

    In the low nutrient environment of conifer bark, subcortical beetles often carry symbiotic fungi that concentrate nutrients in host tissues. Although bark beetles are known to benefit from these symbioses, whether this is because they survive better in nutrient-rich phloem is unknown. After manipulating phloem nutrition by fertilizing lodgepole pine trees (Pinus contorta Douglas var. latifolia), we found bolts from fertilized trees to contain more living individuals, and especially more pupae and teneral adults than bolts from unfertilized trees at our southern site. At our northern site, we found that a larger proportion of mountain pine beetle (Dendroctonus ponderosae Hopkins) larvae built pupal chambers in bolts from fertilized trees than in bolts from unfertilized trees. The symbiotic fungi of the mountain pine beetle also responded to fertilization. Two mutualistic fungi of bark beetles, Grosmannia clavigera (Rob.-Jeffr. & R. W. Davidson) Zipfel, Z. W. de Beer, & M. J. Wingf. and Leptographium longiclavatum Lee, S., J. J. Kim, & C. Breuil, doubled the nitrogen concentrations near the point of infection in the phloem of fertilized trees. These fungi were less capable of concentrating nitrogen in unfertilized trees. Thus, the fungal symbionts of mountain pine beetle enhance phloem nutrition and likely mediate the beneficial effects of fertilization on the survival and development of mountain pine beetle larvae.

  5. Volatile and Within-Needle Terpene Changes to Douglas-fir Trees Associated With Douglas-fir Beetle (Coleoptera: Curculionidae) Attack.

    PubMed

    Giunta, A D; Runyon, J B; Jenkins, M J; Teich, M

    2016-08-01

    Mass attack by tree-killing bark beetles (Curculionidae: Scolytinae) brings about large chemical changes in host trees that can have important ecological consequences. For example, mountain pine beetle (Dendroctonus ponderosae Hopkins) attack increases emission of terpenes by lodgepole pine (Pinus contorta Dougl. ex Loud.), affecting foliage flammability with consequences for wildfires. In this study, we measured chemical changes to Douglas-fir (Pseudotsuga menziesii var. glauca (Mirb.) Franco) foliage in response to attack by Douglas-fir beetles (Dendroctonus pseudotsugae Hopkins) as trees die and crowns transitioned from green/healthy, to green-infested (year of attack), to yellow (year after attack), and red (2 yr after attack). We found large differences in volatile and within-needle terpene concentrations among crown classes and variation across a growing season. In general, emissions and concentrations of total and individual terpenes were greater for yellow and red needles than green needles. Douglas-fir beetle attack increased emissions and concentrations of terpene compounds linked to increased tree flammability in other conifer species and compounds known to attract beetles (e.g., [Formula: see text]-pinene, camphene, and D-limonene). There was little relationship between air temperature or within-needle concentrations of terpenes and emission of terpenes, suggesting that passive emission of terpenes (e.g., from dead foliage) does not fully explain changes in volatile emissions. The potential physiological causes and ecological consequences of these bark beetle-associated chemical changes are discussed. PMID:27231258

  6. Volatile and Within-Needle Terpene Changes to Douglas-fir Trees Associated With Douglas-fir Beetle (Coleoptera: Curculionidae) Attack.

    PubMed

    Giunta, A D; Runyon, J B; Jenkins, M J; Teich, M

    2016-08-01

    Mass attack by tree-killing bark beetles (Curculionidae: Scolytinae) brings about large chemical changes in host trees that can have important ecological consequences. For example, mountain pine beetle (Dendroctonus ponderosae Hopkins) attack increases emission of terpenes by lodgepole pine (Pinus contorta Dougl. ex Loud.), affecting foliage flammability with consequences for wildfires. In this study, we measured chemical changes to Douglas-fir (Pseudotsuga menziesii var. glauca (Mirb.) Franco) foliage in response to attack by Douglas-fir beetles (Dendroctonus pseudotsugae Hopkins) as trees die and crowns transitioned from green/healthy, to green-infested (year of attack), to yellow (year after attack), and red (2 yr after attack). We found large differences in volatile and within-needle terpene concentrations among crown classes and variation across a growing season. In general, emissions and concentrations of total and individual terpenes were greater for yellow and red needles than green needles. Douglas-fir beetle attack increased emissions and concentrations of terpene compounds linked to increased tree flammability in other conifer species and compounds known to attract beetles (e.g., [Formula: see text]-pinene, camphene, and D-limonene). There was little relationship between air temperature or within-needle concentrations of terpenes and emission of terpenes, suggesting that passive emission of terpenes (e.g., from dead foliage) does not fully explain changes in volatile emissions. The potential physiological causes and ecological consequences of these bark beetle-associated chemical changes are discussed.

  7. Mountain pine beetle infestation of lodgepole pine in areas of water diversion.

    PubMed

    Smolinski, Sharon L; Anthamatten, Peter J; Bruederle, Leo P; Barbour, Jon M; Chambers, Frederick B

    2014-06-15

    The Rocky Mountains have experienced extensive infestations from the mountain pine beetle (Dendroctonus ponderosae Hopkins), affecting numerous pine tree species including lodgepole pine (Pinus contorta Dougl. var. latifolia). Water diversions throughout the Rocky Mountains transport large volumes of water out of the basins of origin, resulting in hydrologic modifications to downstream areas. This study examines the hypothesis that lodgepole pine located below water diversions exhibit an increased incidence of mountain pine beetle infestation and mortality. A ground survey verified diversion structures in a portion of Grand County, Colorado, and sampling plots were established around two types of diversion structures, canals and dams. Field studies assessed mountain pine beetle infestation. Lodgepole pines below diversions show 45.1% higher attack and 38.5% higher mortality than lodgepole pines above diversions. These findings suggest that water diversions are associated with increased infestation and mortality of lodgepole pines in the basins of extraction, with implications for forest and water allocation management. PMID:24681362

  8. Mountain pine beetle infestation of lodgepole pine in areas of water diversion.

    PubMed

    Smolinski, Sharon L; Anthamatten, Peter J; Bruederle, Leo P; Barbour, Jon M; Chambers, Frederick B

    2014-06-15

    The Rocky Mountains have experienced extensive infestations from the mountain pine beetle (Dendroctonus ponderosae Hopkins), affecting numerous pine tree species including lodgepole pine (Pinus contorta Dougl. var. latifolia). Water diversions throughout the Rocky Mountains transport large volumes of water out of the basins of origin, resulting in hydrologic modifications to downstream areas. This study examines the hypothesis that lodgepole pine located below water diversions exhibit an increased incidence of mountain pine beetle infestation and mortality. A ground survey verified diversion structures in a portion of Grand County, Colorado, and sampling plots were established around two types of diversion structures, canals and dams. Field studies assessed mountain pine beetle infestation. Lodgepole pines below diversions show 45.1% higher attack and 38.5% higher mortality than lodgepole pines above diversions. These findings suggest that water diversions are associated with increased infestation and mortality of lodgepole pines in the basins of extraction, with implications for forest and water allocation management.

  9. Mountain pine beetle attack associated with low levels of 4-allylanisole in ponderosa pine.

    PubMed

    Emerick, Jay J; Snyder, Aaron I; Bower, Nathan W; Snyder, Marc A

    2008-08-01

    Mountain pine beetle (Dendroctonus ponderosae) is the most important insect pest in southern Rocky Mountain ponderosa pine (Pinus ponderosa) forests. Tree mortality is hastened by the various fungal pathogens that are symbiotic with the beetles. The phenylpropanoid 4-allylanisole is an antifungal and semiochemical for some pine beetle species. We analyzed 4-allylanisole and monoterpene profiles in the xylem oleoresin from a total of 107 trees at six sites from two chemotypes of ponderosa pine found in Colorado and New Mexico using gas chromatography-mass spectroscopy (GC-MS). Although monoterpene profiles were essentially the same in attacked and nonattacked trees, significantly lower levels of 4-allylanisole were found in attacked trees compared with trees that showed no evidence of attack for both chemotypes.

  10. Phloeophagous and predaceous insects responding to synthetic pheromones of bark beetles inhabiting white spruce stands in the Great Lakes region.

    PubMed

    Haberkern, Kirsten E; Raffa, Kenneth F

    2003-07-01

    Tree killing and saprophytic bark beetles exert important ecological and economic roles in North American spruce forests. Chemical signaling among bark beetles, and responses by associate insects such as predators and competitors, have significant effects on the population dynamics and ecology of this community. Synthetic pheromones of primary (tree killing) and secondary (saprophytic) bark beetle species and blank controls were tested using multiple funnel and lower stem flight traps in white spruce forests in Wisconsin, Michigan, and Minnesota. Six phloeophagous and four predaceous species were collected with significant attraction by the bark beetles Dryocoetes affaber, Dryocoetes autographus, and Polygraphus rufipennis, and the predatory checkered beetles (Coleoptera: Cleridae) Thanasimus dubius and Enoclerus nigrifrons. In general, trap catches to synthetic lures resembled the species composition obtained by felling trees and collecting emerging beetles in a companion study, although several species showed differing trends. Some cross attraction occurred among bark beetles and between bark beetles and predatory beetles. For example, P. rufipennis was abundant in traps baited with Dryocoetes spp. pheromones. Thanasimus dubius and E. nigrifrons were collected in significant numbers in traps baited with the pheromone of the spruce beetle (Dendroctonus rufipennis), frontalin plus a-pinene. This is a new observation for E. nigrifrons. Attraction of T. dubius to the pheromones of at least three bark beetle species in the Great Lakes region, as well as to several southern and western species, reflects its role as a habitat specialist and feeding generalist. Several other important predators and competitors commonly obtained in pine forests in this region were not obtained in these spruce stands, either in response to synthetic pheromones of spruce colonizing beetles, or in host material colonized by these beetles. Potential differences in predator prey dynamics

  11. Efficacy of verbenone for protecting ponderosa pine stands from western pine beetle (Coleoptera: Curculionidae: Scolytinae) attack in California.

    PubMed

    Fettig, Christopher J; McKelvey, Stephen R; Borys, Robert R; Dabney, Christopher P; Hamud, Shakeeb M; Nelson, Lori J; Seybold, Steven J

    2009-10-01

    The western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae: Scolytinae), is a major cause of ponderosa pine, Pinus ponderosa Dougl. ex Laws., mortality in much of western North America. Currently, techniques for managing D. brevicomis infestations are limited. Verbenone (4,6,6-trimethylbicyclo [3.1.1] hept-3-en-2-one) is an antiaggregation pheromone of several Dendroctonus spp., including D. brevicomis, and it has been registered as a biopesticide for control of mountain pine beetle, Dendroctonus ponderosae Hopkins, and southern pine beetle, Dendroctonus frontalis Zimmermann. We evaluated the efficacy of a 5-g verbenone pouch [82%-(-); 50 mg/d] applied at 125 Ulha for protecting P. ponderosa stands (2 ha) from D. brevicomis attack over a 3-yr period. No significant differences in levels of D. brevicomis-caused tree mortality or the percentage of unsuccessfully attacked trees were found between verbenone-treated and untreated plots during each year or cumulatively over the 3-yr period. Laboratory analyses of release rates and chemical composition of volatiles emanating from verbenone pouches after field exposure found no deterioration of the active ingredient or physical malfunction of the release device. The mean release rate of pouches from all locations and exposure periods was 44.5 mg/d. In a trapping bioassay, the range of inhibition of the 5-g verbenone pouch was determined to be statistically constant 2 m from the release device. We discuss the implications of these and other results to the development of verbenone as a semiochemical-based tool for management of D. brevicomis infestations in P. ponderosa stands.

  12. Recent mountain pine beetle outbreaks, wildfire severity, and postfire tree regeneration in the US Northern Rockies.

    PubMed

    Harvey, Brian J; Donato, Daniel C; Turner, Monica G

    2014-10-21

    Widespread tree mortality caused by outbreaks of native bark beetles (Circulionidae: Scolytinae) in recent decades has raised concern among scientists and forest managers about whether beetle outbreaks fuel more ecologically severe forest fires and impair postfire resilience. To investigate this question, we collected extensive field data following multiple fires that burned subalpine forests in 2011 throughout the Northern Rocky Mountains across a spectrum of prefire beetle outbreak severity, primarily from mountain pine beetle (Dendroctonus ponderosae). We found that recent (2001-2010) beetle outbreak severity was unrelated to most field measures of subsequent fire severity, which was instead driven primarily by extreme burning conditions (weather) and topography. In the red stage (0-2 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity with few effects detected only under extreme burning conditions. In the gray stage (3-10 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity under moderate conditions, but several measures related to surface fire severity increased with outbreak severity under extreme conditions. Initial postfire tree regeneration of the primary beetle host tree [lodgepole pine (Pinus contorta var. latifolia)] was not directly affected by prefire outbreak severity but was instead driven by the presence of a canopy seedbank and by fire severity. Recent beetle outbreaks in subalpine forests affected few measures of wildfire severity and did not hinder the ability of lodgepole pine forests to regenerate after fire, suggesting that resilience in subalpine forests is not necessarily impaired by recent mountain pine beetle outbreaks. PMID:25267633

  13. Recent mountain pine beetle outbreaks, wildfire severity, and postfire tree regeneration in the US Northern Rockies

    PubMed Central

    Harvey, Brian J.; Donato, Daniel C.; Turner, Monica G.

    2014-01-01

    Widespread tree mortality caused by outbreaks of native bark beetles (Circulionidae: Scolytinae) in recent decades has raised concern among scientists and forest managers about whether beetle outbreaks fuel more ecologically severe forest fires and impair postfire resilience. To investigate this question, we collected extensive field data following multiple fires that burned subalpine forests in 2011 throughout the Northern Rocky Mountains across a spectrum of prefire beetle outbreak severity, primarily from mountain pine beetle (Dendroctonus ponderosae). We found that recent (2001–2010) beetle outbreak severity was unrelated to most field measures of subsequent fire severity, which was instead driven primarily by extreme burning conditions (weather) and topography. In the red stage (0–2 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity with few effects detected only under extreme burning conditions. In the gray stage (3–10 y following beetle outbreak), fire severity was largely unaffected by prefire outbreak severity under moderate conditions, but several measures related to surface fire severity increased with outbreak severity under extreme conditions. Initial postfire tree regeneration of the primary beetle host tree [lodgepole pine (Pinus contorta var. latifolia)] was not directly affected by prefire outbreak severity but was instead driven by the presence of a canopy seedbank and by fire severity. Recent beetle outbreaks in subalpine forests affected few measures of wildfire severity and did not hinder the ability of lodgepole pine forests to regenerate after fire, suggesting that resilience in subalpine forests is not necessarily impaired by recent mountain pine beetle outbreaks. PMID:25267633

  14. Pheromone Production by an Invasive Bark Beetle Varies with Monoterpene Composition of its Naïve Host.

    PubMed

    Taft, Spencer; Najar, Ahmed; Erbilgin, Nadir

    2015-06-01

    The secondary chemistry of host plants can have cascading impacts on the establishment of new insect herbivore populations, their long-term population dynamics, and their invasion potential in novel habitats. Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae) has recently expanded its range into forests of jack pine, Pinus banksiana Lamb., in western Canada. We investigated whether variations in jack pine monoterpenes affect beetle pheromone production, as the primary components of the beetle's aggregation pheromone, (-)-trans-verbenol and anti-aggregation pheromone (-)-verbenone, are biosynthesized from the host monoterpene α-pinene. Jack pine bolts were collected from five Canadian provinces east of the beetle's current range, live D. ponderosae were introduced into them, and their monoterpene compositions were characterized. Production of (-)-trans-verbenol and (-)-verbenone emitted by beetles was measured to determine whether pheromone production varies with monoterpene composition of jack pines. Depending on particular ratios of major monoterpenes in host phloem, jack pine could be classified into three monoterpenoid groups characterized by high amounts of (+)-α-pinene, 3-carene, or a more moderate blend of monoterpenes, and beetle pheromone production varied among these groups. Specifically, beetles reared in trees characterized by high (+)-α-pinene produced the most (-)-trans-verbenol and (-)-verbenone, while beetles in trees characterized by high 3-carene produced the least. Our results indicate that pheromone production by D. ponderosae will remain a significant aspect and important predictor of its survival and persistence in the boreal forest.

  15. The complex symbiotic relationships of bark beetles with microorganisms: a potential practical approach for biological control in forestry.

    PubMed

    Popa, Valentin; Déziel, Eric; Lavallée, Robert; Bauce, Eric; Guertin, Claude

    2012-07-01

    Bark beetles, especially Dendroctonus species, are considered to be serious pests of the coniferous forests in North America. Bark beetle forest pests undergo population eruptions, causing region wide economic losses. In order to save forests, finding new and innovative environmentally friendly approaches in wood-boring insect pest management is more important than ever. Several biological control methods have been attempted over time to limit the damage and spreading of bark beetle epidemics. The use of entomopathogenic microorganisms against bark beetle populations is an attractive alternative tool for many biological control programmes in forestry. However, the effectiveness of these biological control agents is strongly affected by environmental factors, as well as by the susceptibility of the insect host. Bark beetle susceptibility to entomopathogens varies greatly between species. According to recent literature, bark beetles are engaged in symbiotic relationships with fungi and bacteria. These types of relationship are very complex and apparently involved in bark beetle defensive mechanisms against pathogens. The latest scientific discoveries in multipartite symbiosis have unravelled unexpected opportunities in bark beetle pest management, which are discussed in this article. PMID:22566204

  16. A Novel Semiochemical Tool for Protecting Pinus contorta From Mortality Attributed to Dendroctonus ponderosae (Coleoptera: Curculionidae).

    PubMed

    Fettig, Christopher J; Munson, A Steven; Reinke, Michael; Mafra-Neto, Agenor

    2015-02-01

    Verbenone (4,6,6-trimethylbicyclo[3.1.1]hept-3-en-2-one) is an antiaggregant of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), a notable forest insect capable of causing extensive levels of tree mortality in western North America. Several formulations of verbenone are registered for tree protection, but failures in efficacy are not uncommon, particularly when applied during large infestations. A formulation of (-)-verbenone was developed (Specialized Pheromone & Lure Application Technology [SPLAT] Verb, ISCA Technologies Inc., Riverside, CA) and evaluated for protecting individual lodgepole pine, Pinus contorta Douglas ex Loudon, and small stands of P. contorta from mortality attributed to D. ponderosae. SPLAT Verb applied to individual P. contorta resulted in complete tree protection, while 93.3% mortality occurred in the untreated controls. Significantly fewer P. contorta were killed by D. ponderosae within 0.041-ha circular plots surrounding P. contorta treated with SPLAT Verb compared with the untreated control. In a second study, a smaller percentage of P. contorta were colonized and killed on 0.4-ha square plots treated with SPLAT Verb compared with the untreated control. No significant differences in levels of tree mortality were observed between the untreated control and another formulation of verbenone (7-g pouch) or between the 7-g pouch and SPLAT Verb. In a trapping bioassay, no significant differences were observed among captures in multiple-funnel traps at 1, 2, or 4 m from the point of release of SPLAT Verb. Significantly fewer D. ponderosae were collected at 1 and 2 m compared with 8 m. Significantly more D. ponderosae were captured at the farthest distance evaluated (16 m) than at any other distance. Our data indicate that SPLAT Verb is effective for protecting individual P. contorta and small stands of P. contorta from mortality attributed to D. ponderosae at moderate doses. The high levels of tree

  17. A Novel Semiochemical Tool for Protecting Pinus contorta From Mortality Attributed to Dendroctonus ponderosae (Coleoptera: Curculionidae).

    PubMed

    Fettig, Christopher J; Munson, A Steven; Reinke, Michael; Mafra-Neto, Agenor

    2015-02-01

    Verbenone (4,6,6-trimethylbicyclo[3.1.1]hept-3-en-2-one) is an antiaggregant of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), a notable forest insect capable of causing extensive levels of tree mortality in western North America. Several formulations of verbenone are registered for tree protection, but failures in efficacy are not uncommon, particularly when applied during large infestations. A formulation of (-)-verbenone was developed (Specialized Pheromone & Lure Application Technology [SPLAT] Verb, ISCA Technologies Inc., Riverside, CA) and evaluated for protecting individual lodgepole pine, Pinus contorta Douglas ex Loudon, and small stands of P. contorta from mortality attributed to D. ponderosae. SPLAT Verb applied to individual P. contorta resulted in complete tree protection, while 93.3% mortality occurred in the untreated controls. Significantly fewer P. contorta were killed by D. ponderosae within 0.041-ha circular plots surrounding P. contorta treated with SPLAT Verb compared with the untreated control. In a second study, a smaller percentage of P. contorta were colonized and killed on 0.4-ha square plots treated with SPLAT Verb compared with the untreated control. No significant differences in levels of tree mortality were observed between the untreated control and another formulation of verbenone (7-g pouch) or between the 7-g pouch and SPLAT Verb. In a trapping bioassay, no significant differences were observed among captures in multiple-funnel traps at 1, 2, or 4 m from the point of release of SPLAT Verb. Significantly fewer D. ponderosae were collected at 1 and 2 m compared with 8 m. Significantly more D. ponderosae were captured at the farthest distance evaluated (16 m) than at any other distance. Our data indicate that SPLAT Verb is effective for protecting individual P. contorta and small stands of P. contorta from mortality attributed to D. ponderosae at moderate doses. The high levels of tree

  18. Expression, purification and characterization of an endoglucanase from Serratia proteamaculans CDBB-1961, isolated from the gut of Dendroctonus adjunctus (Coleoptera: Scolytinae).

    PubMed

    Cano-Ramírez, Claudia; Santiago-Hernández, Alejandro; Rivera-Orduña, Flor Nohemí; García-Huante, Yolanda; Zúñiga, Gerardo; Hidalgo-Lara, María Eugenia

    2016-12-01

    Serratia proteamaculans CDBB-1961, a gut symbiont from the roundheaded pine beetle Dendroctonus adjunctus, displayed strong cellulolytic activity on agar-plates with carboxymethyl cellulose (CMC) as carbon source. Automatic genome annotation of S. proteamaculans made possible the identification of a single endoglucanase encoding gene, designated spr cel8A. The predicted protein, named Spr Cel8A shows high similarity (59-94 %) to endo-1,4-β-D-glucanases (EC 3.2.1.4) from the glycoside hydrolase family 8 (GH8). The gene spr cel8A has an ORF of 1113 bp, encoding a 371 amino acid residue protein (41.2 kDa) with a signal peptide of 23 amino acid residues. Expression of the gene spr cel8A in Escherichia coli yields a mature recombinant endoglucanase 39 kDa. Cel8A displayed optimal activity at pH 7.0 and 40 °C, with a specific activity of 0.85 U/mg. The enzyme was stable at pH from 4 to 8.5, retaining nearly 40-80 % of its original activity, and exhibited a half-life of 8 days at 40 °C. The K m and V max values for Spr Cel8A were 6.87 mg/ml and 3.5 μmol/min/mg of protein, respectively, using CMC as substrate. The final principle products of Spr Cel8A-mediated hydrolysis of CMC were cellobiose, cello oligosaccharides and a small amount of glucose, suggesting that Spr Cel8A is an endo-β-1,4-glucanase manifesting exo-activity. This is the first report regarding the functional biochemical and molecular characterization of an endoglucanase from S. proteamaculans, found in the gut-associated bacteria community of Dendroctonus bark beetles. These results contribute to improved understanding of the functional role played by this bacterium as a symbiont of bark beetles.

  19. Expression, purification and characterization of an endoglucanase from Serratia proteamaculans CDBB-1961, isolated from the gut of Dendroctonus adjunctus (Coleoptera: Scolytinae).

    PubMed

    Cano-Ramírez, Claudia; Santiago-Hernández, Alejandro; Rivera-Orduña, Flor Nohemí; García-Huante, Yolanda; Zúñiga, Gerardo; Hidalgo-Lara, María Eugenia

    2016-12-01

    Serratia proteamaculans CDBB-1961, a gut symbiont from the roundheaded pine beetle Dendroctonus adjunctus, displayed strong cellulolytic activity on agar-plates with carboxymethyl cellulose (CMC) as carbon source. Automatic genome annotation of S. proteamaculans made possible the identification of a single endoglucanase encoding gene, designated spr cel8A. The predicted protein, named Spr Cel8A shows high similarity (59-94 %) to endo-1,4-β-D-glucanases (EC 3.2.1.4) from the glycoside hydrolase family 8 (GH8). The gene spr cel8A has an ORF of 1113 bp, encoding a 371 amino acid residue protein (41.2 kDa) with a signal peptide of 23 amino acid residues. Expression of the gene spr cel8A in Escherichia coli yields a mature recombinant endoglucanase 39 kDa. Cel8A displayed optimal activity at pH 7.0 and 40 °C, with a specific activity of 0.85 U/mg. The enzyme was stable at pH from 4 to 8.5, retaining nearly 40-80 % of its original activity, and exhibited a half-life of 8 days at 40 °C. The K m and V max values for Spr Cel8A were 6.87 mg/ml and 3.5 μmol/min/mg of protein, respectively, using CMC as substrate. The final principle products of Spr Cel8A-mediated hydrolysis of CMC were cellobiose, cello oligosaccharides and a small amount of glucose, suggesting that Spr Cel8A is an endo-β-1,4-glucanase manifesting exo-activity. This is the first report regarding the functional biochemical and molecular characterization of an endoglucanase from S. proteamaculans, found in the gut-associated bacteria community of Dendroctonus bark beetles. These results contribute to improved understanding of the functional role played by this bacterium as a symbiont of bark beetles. PMID:27576896

  20. Modeling compensatory responses of ecosystem-scale water fluxes in forests affected by pine and spruce beetle mortality

    NASA Astrophysics Data System (ADS)

    Millar, D.; Ewers, B. E.; Peckham, S. D.; Mackay, D. S.; Frank, J. M.; Massman, W. J.; Reed, D. E.

    2015-12-01

    Mountain pine beetle (Dendroctonus ponderosae) and spruce beetle (Dendroctonus rufipennis) epidemics have led to extensive mortality in lodgepole pine (Pinus contorta) and Engelmann spruce (Picea engelmannii) forests in the Rocky Mountains of the western US. In both of these tree species, mortality results from hydraulic failure within the xylem, due to blue stain fungal infection associated with beetle attack. However, the impacts of these disturbances on ecosystem-scale water fluxes can be complex, owing to their variable and transient nature. In this work, xylem scaling factors that reduced whole-tree conductance were initially incorporated into a forest ecohydrological model (TREES) to simulate the impact of beetle mortality on evapotranspiration (ET) in both pine and spruce forests. For both forests, simulated ET was compared to observed ET fluxes recorded using eddy covariance techniques. Using xylem scaling factors, the model overestimated the impact of beetle mortality, and observed ET fluxes were approximately two-fold higher than model predictions in both forests. The discrepancy between simulated and observed ET following the onset of beetle mortality may be the result of spatial and temporal heterogeneity of plant communities within the foot prints of the eddy covariance towers. Since simulated ET fluxes following beetle mortality in both forests only accounted for approximately 50% of those observed in the field, it is possible that newly established understory vegetation in recently killed tree stands may play a role in stabilizing ecosystem ET fluxes. Here, we further investigate the unaccounted for ET fluxes in the model by breaking it down into multiple cohorts that represent live trees, dying trees, and understory vegetation that establishes following tree mortality.

  1. Colonization of disturbed trees by the southern pine bark beetle guild (Coleoptera: Scolytidae)

    SciTech Connect

    Flamm, R.O.; Pulley, P.E.; Coulson, R.N. )

    1993-02-01

    The southern pine bark beetle guild [Dendroctonus frontalis Zimmermann, D. terebrans (Olivier), Ips calligraphus (Germar), I. grandicollis (Eichhoff), and I. avulsus (Eichhoff)] uses disturbed hosts as habitat for establishment of within-tree populations. The process of colonization of disturbed hosts was examined. Using a procedure designed to emulate effects of a lightning strike, pines were severely disturbed. Response was characterized by measuring beetle populations that (1) arrived at the trees and (2) successfully attacked the trees. Establishment of within-tree populations was characterized by measuring length of egg gallery excavated by attacking adults. The time delay between arrival and attack for D. frontalis and I. calligraphus was also calculated. Attack densities of both species became asymptotic as arrival increased. The percentage of arriving beetles that attacked ranged from 9 to 41 for D. frontalis and from 8 to 59 for I. calligraphus. Numbers of beetles that arrived at the tree but did not attack ranged from 2.7 to 50.2 beetles per dm[sup 2] for D. frontalis and from 0.2 to 10.0 beetles per dm[sup 2] for I. calligraphus. Most D. frontalis and I. calligraphus attacked on the day they arrived. The delay between arrival and attack was longer for I. calligraphus than the D. frontalis. Egg gallery excavated by D. frontalis increased throughout the study. Eventually, the Ips species were excluded from the lower half of the hole. The low attack densities observed in this study illustrate the significance of disturbed trees in providing refuges for enzootic levels of bark beetles. The aggregation behavior of beetle populations colonizing disturbed hosts supported the contention that these trees serve as foci for initiation of infestations. Furthermore, in disturbed pines, small numbers of beetles were capable of overcoming host defense systems.

  2. Competition and coexistence in a multi-partner mutualism: interactions between two fungal symbionts of the mountain pine beetle in beetle-attacked trees.

    PubMed

    Bleiker, K P; Six, D L

    2009-01-01

    Despite overlap in niches, two fungal symbionts of the mountain pine beetle (Dendroctonus ponderosae), Grosmannia clavigera and Ophiostoma montium, appear to coexist with one another and their bark beetle host in the phloem of trees. We sampled the percent of phloem colonized by fungi four times over 1 year to investigate the nature of the interaction between these two fungi and to determine how changing conditions in the tree (e.g., moisture) affect the interaction. Both fungi colonized phloem at similar rates; however, G. clavigera colonized a disproportionately larger amount of phloem than O. montium considering their relative prevalence in the beetle population. High phloem moisture appeared to inhibit fungal growth shortly after beetle attack; however, by 1 year, low phloem moisture likely inhibited fungal growth and survival. There was no inverse relationship between the percent of phloem colonized by G. clavigera only and O. montium only, which would indicate competition between the species. However, the percent of phloem colonized by G. clavigera and O. montium together decreased after 1 year, while the percent of phloem from which no fungi were isolated increased. A reduction in living fungi in the phloem at this time may have significant impacts on both beetles and fungi. These results indicate that exploitation competition occurred after a year when the two fungi colonized the phloem together, but we found no evidence of strong interference competition. Each species also maintained an exclusive area, which may promote coexistence of species with similar resource use.

  3. Assessing forest vulnerability and the potential distribution of pine beetles under current and future climate scenarios in the Interior West of the US

    USGS Publications Warehouse

    Evangelista, P.H.; Kumar, S.; Stohlgren, T.J.; Young, N.E.

    2011-01-01

    The aim of our study was to estimate forest vulnerability and potential distribution of three bark beetles (Curculionidae: Scolytinae) under current and projected climate conditions for 2020 and 2050. Our study focused on the mountain pine beetle (Dendroctonus ponderosae), western pine beetle (Dendroctonus brevicomis), and pine engraver (Ips pini). This study was conducted across eight states in the Interior West of the US covering approximately 2.2millionkm2 and encompassing about 95% of the Rocky Mountains in the contiguous US. Our analyses relied on aerial surveys of bark beetle outbreaks that occurred between 1991 and 2008. Occurrence points for each species were generated within polygons created from the aerial surveys. Current and projected climate scenarios were acquired from the WorldClim database and represented by 19 bioclimatic variables. We used Maxent modeling technique fit with occurrence points and current climate data to model potential beetle distributions and forest vulnerability. Three available climate models, each having two emission scenarios, were modeled independently and results averaged to produce two predictions for 2020 and two predictions for 2050 for each analysis. Environmental parameters defined by current climate models were then used to predict conditions under future climate scenarios, and changes in different species' ranges were calculated. Our results suggested that the potential distribution for bark beetles under current climate conditions is extensive, which coincides with infestation trends observed in the last decade. Our results predicted that suitable habitats for the mountain pine beetle and pine engraver beetle will stabilize or decrease under future climate conditions, while habitat for the western pine beetle will continue to increase over time. The greatest increase in habitat area was for the western pine beetle, where one climate model predicted a 27% increase by 2050. In contrast, the predicted habitat of the

  4. Effectiveness of bifenthrin (Onyx) and carbaryl (Sevin SL) for protecting individual, high-value conifers from bark beetle attack (Coleoptera: Curculionidae: Scolytinae) in the Western United States.

    PubMed

    Fettig, Christopher J; Allen, Kurt K; Borys, Robert R; Christopherson, John; Dabney, Christopher P; Eager, Thomas J; Gibson, Kenneth E; Hebertson, Elizabeth G; Long, Daniel F; Munson, A Steven; Shea, Patrick J; Smith, Sheri L; Haverty, Michael I

    2006-10-01

    High-value trees, such as those located in residential, recreational, or administrative sites, are particularly susceptible to bark beetle (Coleoptera: Curculionidae: Scolytinae) attack as a result of increased amounts of stress associated with drought, soil compaction, mechanical injury, or vandalism. Tree losses in these unique environments generally have a substantial impact. The value of these individual trees, cost of removal, and loss of esthetics may justify protection until the main thrust of a bark beetle infestation subsides. This situation emphasizes the need for ensuring that effective insecticides are available for individual tree protection. In this study, we assess the efficacy of bifenthrin (Onyx) and carbaryl (Sevin SL) for protecting: ponderosa pine, Pinus ponderosa Dougl. ex. Laws., from western pine beetle, Dendroctonus brevicomis LeConte, in California; mountain pine beetle, Dendroctonus ponderosae Hopkins in South Dakota; and Ips spp. in Arizona; lodgepole pine, Pinus contorta Dougl. ex Loud., from D. ponderosae in Montana; pinyon, Pinus edulis Engelm. in Colorado and Pinus monophylla Torr. and Frem. in Nevada from pinyon ips, Ips confusus (LeConte); and Engelmann spruce, Picea engelmannii Parry ex. Engelm. from spruce beetle, Dendroctonus rufipennis (Kirby) in Utah. Few trees were attacked by Ips spp. in Arizona and that study was discontinued. Sevin SL (2.0%) was effective for protecting P. ponderosa, P. contorta, and P. monophylla for two field seasons. Estimates of efficacy could not be made during the second field season in P. edulis and P. engelmannii due to insufficient mortality in untreated, baited control trees. Two field seasons of efficacy was demonstrated in P. ponderosa/D. brevicomis and P. monophylla for 0.06% Onyx. We conclude that Onyx is an effective individual tree protection tool, but repeated annual applications may be required in some systems if multiyear control is desired.

  5. Mountain pine beetle impacts on vegetation and carbon stocks

    USGS Publications Warehouse

    Hawbaker, Todd J.; Briggs, Jennifer S.; Caldwell, Megan K.; Stitt, Susan

    2013-01-01

    In the Southern Rocky Mountains, an epidemic outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused levels of tree mortality unprecedented in recorded history. The impacts of this mortality on vegetation composition, forest structure, and carbon stocks have only recently received attention, although the impacts of other disturbances such as fires and land-use/land-cover change are much better known. This study, initiated in 2010, aims to increase our understanding of MPB outbreaks and their impacts. We have integrated field-collected data with vegetation simulation models to assess and quantify how long-term patterns of vegetation and carbon stocks have and may change in response to MPB outbreaks and other disturbances.

  6. Nonstructural carbohydrate dynamics of lodgepole pine dying from mountain pine beetle attack.

    PubMed

    Wiley, Erin; Rogers, Bruce J; Hodgkinson, Robert; Landhäusser, Simon M

    2016-01-01

    Bark beetle outbreaks are an important cause of tree death, but the process by which trees die remains poorly understood. The effect of beetle attack on whole-tree nonstructural carbohydrate (NSC) dynamics is particularly unclear, despite the potential role of carbohydrates in plant defense and survival. We monitored NSC dynamics of all organs in attacked and protected lodgepole pines (Pinus contorta) during a mountain pine beetle (Dendroctonus ponderosae) outbreak in British Columbia, starting before beetle flight in June 2011 through October 2012, when most attacked trees had died. Following attack, NSC concentrations were first reduced in the attacked region of the bole. The first NSC reduction in a distant organ appeared in the needles at the end of 2011, while branch and root NSC did not decline until much later in 2012. Attacked trees that were still alive in October 2012 had less beetle damage, which was negatively correlated with initial bark sugar concentrations in the attack region. The NSC dynamics of dying trees indicate that trees were killed by a loss of water conduction and not girdling. Further, our results identify locally reduced carbohydrate availability as an important mechanism by which stressors like drought may increase tree susceptibility to biotic attack. PMID:26256444

  7. Hydrological Response to Mountain Pine Beetle Infestation in Western Subalpine Watersheds

    NASA Astrophysics Data System (ADS)

    Elder, K.; Porth, L.; Hubbard, R.; Rhoades, C.; Dixon, M.

    2008-12-01

    Water supply in western North America is controlled primarily by snow accumulation and melt in forested headwater basins. Trees impact runoff through wintertime canopy interception losses of snowfall and summertime transpiration losses. The mountain pine beetle (Dendroctonus ponderosae) epidemic attacking western pine forests will produce an estimated 90% mortality in lodgepole (Pinus contorta) stands, and will likely impact other tree species at significant levels over large areas of the US and Canada. Management studies suggest that changes in water quantity and quality will occur in response to beetle induced tree mortality. Hydrological responses in beetle killed forests are dependent on local climatology, forest age and species composition, understory response, and severity of infestation. Changes in discharge measured at the watershed level are typically quantified using statistical methods applied to time series data. Critical analysis elements are stationarity, and a sufficient data record for statistically significant detection of change. Short-term studies comparing statistical properties of flow often lack these critical elements and should be examined with caution. We show why short-term studies related to pine beetle impact on hydrology are unreliable. During the past five years, significant forest mortality has resulted from the current bark beetle epidemic, yet double mass plots using control basins and analysis of covariance (ANCOVA) show no significant response to date.

  8. Linking Stream Nitrate to Forest Response and Recovery after Severe Bark Beetle Infestation (Invited)

    NASA Astrophysics Data System (ADS)

    Rhoades, C.; Hubbard, R. M.; Elder, K.

    2013-12-01

    Biogeochemical responses and ecosystem recovery from bark beetle outbreaks are influenced by pre-disturbance forest structure and composition and catchment conditions. Over the past decade, the mountain pine bark beetle (Dendroctonus ponderosae) has killed mature lodgepole pine (Pinus contorta) trees at the Fraser Experimental Forest and throughout the Colorado Rockies. Here we compare stream nitrogen (N) concentrations during the outbreak with data from the previous two decades in four research catchments with distinct forest management history, stand age structure and watershed characteristics. In two old growth forest catchments, stream nitrate concentrations were significantly higher during the infestation in the snowmelt and base flow seasons. The beetle infestation elevated nitrate export 43 and 74% in these two catchments though the amounts of N released in streamwater (0.04 and 0.15 kg N ha-1) were < 2% of annual atmospheric inputs. In contrast, nitrate concentrations were unaffected by beetle infestation in two catchments comprised of a mixture of second-growth (30-60 year old) and old-growth (250-350 year old) forest stands where the density of residual live trees was higher on average. Mortality of overstory trees from bark beetles has stimulated the growth of understory and overstory trees with likely consequences for nutrient demand and retention in recovering forests.

  9. Recent bark beetle outbreaks have little impact on streamflow in the Western United States

    NASA Astrophysics Data System (ADS)

    Slinski, Kimberly M.; Hogue, Terri S.; Porter, Aaron T.; McCray, John E.

    2016-07-01

    In the Western United States (US), the current mountain pine beetle (MPB; Dendroctonus ponderosae) epidemic has affected more than five million hectares since its start in 1996, including headwater catchments that supply water to much of the Western US. There is widespread concern that the hydrologic consequences of the extensive pine tree die-off will impact water supply across the Western US. While forest disturbance studies have shown that streamflow increases in response to tree harvest, the actual effect of bark beetle infestations on water supply remains widely debated. The current study evaluates watershed-level response following bark beetle outbreak for 33 watersheds in seven western states. Streamflow records were investigated to assess whether the timing and amount of stream discharge during bark beetle outbreak and early recovery periods were significantly different to pre-outbreak conditions. Results show no significant modification in peak flows or average daily streamflow following bark beetle infestation, and that climate variability may be a stronger driver of streamflow patterns and snowmelt timing than chronic forest disturbance.

  10. Nonstructural carbohydrate dynamics of lodgepole pine dying from mountain pine beetle attack.

    PubMed

    Wiley, Erin; Rogers, Bruce J; Hodgkinson, Robert; Landhäusser, Simon M

    2016-01-01

    Bark beetle outbreaks are an important cause of tree death, but the process by which trees die remains poorly understood. The effect of beetle attack on whole-tree nonstructural carbohydrate (NSC) dynamics is particularly unclear, despite the potential role of carbohydrates in plant defense and survival. We monitored NSC dynamics of all organs in attacked and protected lodgepole pines (Pinus contorta) during a mountain pine beetle (Dendroctonus ponderosae) outbreak in British Columbia, starting before beetle flight in June 2011 through October 2012, when most attacked trees had died. Following attack, NSC concentrations were first reduced in the attacked region of the bole. The first NSC reduction in a distant organ appeared in the needles at the end of 2011, while branch and root NSC did not decline until much later in 2012. Attacked trees that were still alive in October 2012 had less beetle damage, which was negatively correlated with initial bark sugar concentrations in the attack region. The NSC dynamics of dying trees indicate that trees were killed by a loss of water conduction and not girdling. Further, our results identify locally reduced carbohydrate availability as an important mechanism by which stressors like drought may increase tree susceptibility to biotic attack.

  11. Fungal Volatiles Can Act as Carbon Sources and Semiochemicals to Mediate Interspecific Interactions Among Bark Beetle-Associated Fungal Symbionts.

    PubMed

    Cale, Jonathan A; Collignon, R Maxwell; Klutsch, Jennifer G; Kanekar, Sanat S; Hussain, Altaf; Erbilgin, Nadir

    2016-01-01

    Mountain pine beetle (Dendroctonus ponderosae) has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs) help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle's fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success. PMID:27583519

  12. Spatial Genetic Structure of a Symbiotic Beetle-Fungal System: Toward Multi-Taxa Integrated Landscape Genetics

    PubMed Central

    James, Patrick M. A.; Coltman, Dave W.; Murray, Brent W.; Hamelin, Richard C.; Sperling, Felix A. H.

    2011-01-01

    Spatial patterns of genetic variation in interacting species can identify shared features that are important to gene flow and can elucidate co-evolutionary relationships. We assessed concordance in spatial genetic variation between the mountain pine beetle (Dendroctonus ponderosae) and one of its fungal symbionts, Grosmanniaclavigera, in western Canada using neutral genetic markers. We examined how spatial heterogeneity affects genetic variation within beetles and fungi and developed a novel integrated landscape genetics approach to assess reciprocal genetic influences between species using constrained ordination. We also compared landscape genetic models built using Euclidean distances based on allele frequencies to traditional pair-wise Fst. Both beetles and fungi exhibited moderate levels of genetic structure over the total study area, low levels of structure in the south, and more pronounced fungal structure in the north. Beetle genetic variation was associated with geographic location while that of the fungus was not. Pinevolume and climate explained beetle genetic variation in the northern region of recent outbreak expansion. Reciprocal genetic relationships were only detectedin the south where there has been alonger history of beetle infestations. The Euclidean distance and Fst-based analyses resulted in similar models in the north and over the entire study area, but differences between methods in the south suggest that genetic distances measures should be selected based on ecological and evolutionary contexts. The integrated landscape genetics framework we present is powerful, general, and can be applied to other systems to quantify the biotic and abiotic determinants of spatial genetic variation within and among taxa. PMID:21991309

  13. Fungal Volatiles Can Act as Carbon Sources and Semiochemicals to Mediate Interspecific Interactions Among Bark Beetle-Associated Fungal Symbionts.

    PubMed

    Cale, Jonathan A; Collignon, R Maxwell; Klutsch, Jennifer G; Kanekar, Sanat S; Hussain, Altaf; Erbilgin, Nadir

    2016-01-01

    Mountain pine beetle (Dendroctonus ponderosae) has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs) help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle's fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success.

  14. Effects of thinning on temperature dynamics and mountain pine beetle activity in a lodgepole pine stand. Forest Service research paper

    SciTech Connect

    Bartos, D.L.; Booth, G.D.

    1994-12-01

    Temperature measurements were made to better understand the role of microclimate on mountain pine beetle, Dendroctonus pondersae Hopkins (Coleoptera:Scolytidae), activity as a result of thinning lodgepole pine stands. Sampling was done over 61 days on the north slope of the Unita Mountain Range in Northeastern Utah. Principal components analysis was applied to all temperature variables. Most of the variation was attributed to two variables, coolest part of the night and hottest part of the day. The thinned stand was approximately 1 deg. C warmer than the unthinned stand.

  15. Developmental mortality increases sex-ratio bias of a size-dimorphic bark beetle.

    PubMed

    Lachowsky, Leanna E; Reid, Mary L

    2014-06-01

    1. Given sexual size dimorphism, differential mortality owing to body size can lead to sex-biased mortality, proximately biasing sex ratios. This mechanism may apply to mountain pine beetles, Dendroctonus ponderosae Hopkins, which typically have female-biased adult populations (2 : 1) with females larger than males. Smaller males could be more susceptible to stresses than larger females as developing beetles overwinter and populations experience high mortality. 2. Survival of naturally-established mountain pine beetles during the juvenile stage and the resulting adult sex ratios and body sizes (volume) were studied. Three treatments were applied to vary survival in logs cut from trees containing broods of mountain pine beetles. Logs were removed from the forest either in early winter, or in spring after overwintering below snow or after overwintering above snow. Upon removal, logs were placed at room temperature to allow beetles to complete development under similar conditions. 3. Compared with beetles from logs removed in early winter, mortality was higher and the sex ratio was more female-biased in overwintering logs. The bias increased with overwinter mortality. However, sex ratios were female-biased even in early winter, so additional mechanisms, other than overwintering mortality, contributed to the sex-ratio bias. Body volume varied little relative to sex-biased mortality, suggesting other size-independent causes of male-biased mortality. 4. Overwintering mortality is considered a major determinant of mountain pine beetle population dynamics. The disproportionate survival of females, who initiate colonisation of live pine trees, may affect population dynamics in ways that have not been previously considered.

  16. Genetic Diversity and the Presence of Two Distinct Groups in Ophiostoma clavigerum Associated with Dendroctonus ponderosae in British Columbia and the Northern Rocky Mountains.

    PubMed

    Lee, S; Hamelin, R C; Six, D L; Breuil, C

    2007-09-01

    ABSTRACT The sapstaining fungal pathogen Ophiostoma clavigerum is associated with the mountain pine beetle (Dendroctonus ponderosae), which is currently the most destructive forest pest in North America. The genetic diversity of O. clavigerum populations collected from five sites in Canada and two sites in the United States was estimated with amplified fragment length polymorphism (AFLP) analysis. Genomic DNA from 170 O. clavigerum isolates was digested with EcoRI and PstI and amplified with six primer sets. A total of 469 AFLP markers consisting of 243 monomorphic and 226 polymorphic loci were scored. The overall genetic diversity of the O. clavigerum population was low (Hs = 0.0531) and the differentiation of the seven O. clavigerum populations was moderate (Phi = 0.143). Genetic distances among the populations were not significantly correlated with geographic distance (r = 0.3235, P = 0.074). Two genetically distinct groups in the O. clavigerum populations were shown by unique AFLP profiles and the unweighted pair group method with arithmetic averages. Further work to characterize biological differences between the two groups will be needed to confirm whether cryptic species are present in the O. clavigerum population. PMID:18944182

  17. Genetic Diversity and the Presence of Two Distinct Groups in Ophiostoma clavigerum Associated with Dendroctonus ponderosae in British Columbia and the Northern Rocky Mountains.

    PubMed

    Lee, S; Hamelin, R C; Six, D L; Breuil, C

    2007-09-01

    ABSTRACT The sapstaining fungal pathogen Ophiostoma clavigerum is associated with the mountain pine beetle (Dendroctonus ponderosae), which is currently the most destructive forest pest in North America. The genetic diversity of O. clavigerum populations collected from five sites in Canada and two sites in the United States was estimated with amplified fragment length polymorphism (AFLP) analysis. Genomic DNA from 170 O. clavigerum isolates was digested with EcoRI and PstI and amplified with six primer sets. A total of 469 AFLP markers consisting of 243 monomorphic and 226 polymorphic loci were scored. The overall genetic diversity of the O. clavigerum population was low (Hs = 0.0531) and the differentiation of the seven O. clavigerum populations was moderate (Phi = 0.143). Genetic distances among the populations were not significantly correlated with geographic distance (r = 0.3235, P = 0.074). Two genetically distinct groups in the O. clavigerum populations were shown by unique AFLP profiles and the unweighted pair group method with arithmetic averages. Further work to characterize biological differences between the two groups will be needed to confirm whether cryptic species are present in the O. clavigerum population.

  18. Chemical similarity between historical and novel host plants promotes range and host expansion of the mountain pine beetle in a naïve host ecosystem.

    PubMed

    Erbilgin, Nadir; Ma, Cary; Whitehouse, Caroline; Shan, Bin; Najar, Ahmed; Evenden, Maya

    2014-02-01

    Host plant secondary chemistry can have cascading impacts on host and range expansion of herbivorous insect populations. We investigated the role of host secondary compounds on pheromone production by the mountain pine beetle (Dendroctonus ponderosae) (MPB) and beetle attraction in response to a historical (lodgepole pine, Pinus contorta var. latifolia) and a novel (jack pine, Pinus banksiana) hosts, as pheromones regulate the host colonization process. Beetles emit the same pheromones from both hosts, but more trans-verbenol, the primary aggregation pheromone, was emitted by female beetles on the novel host. The phloem of the novel host contains more α-pinene, a secondary compound that is the precursor for trans-verbenol production in beetle, than the historical host. Beetle-induced emission of 3-carene, another secondary compound found in both hosts, was also higher from the novel host. Field tests showed that the addition of 3-carene to the pheromone mixture mimicking the aggregation pheromones produced from the two host species increased beetle capture. We conclude that chemical similarity between historical and novel hosts has facilitated host expansion of MPB in jack pine forests through the exploitation of common host secondary compounds for pheromone production and aggregation on the hosts. Furthermore, broods emerging from the novel host were larger in terms of body size. PMID:24400902

  19. Population densities and tree diameter effects associated with verbenone treatments to reduce mountain pine beetle-caused mortality of lodgepole pine.

    PubMed

    Progar, R A; Blackford, D C; Cluck, D R; Costello, S; Dunning, L B; Eager, T; Jorgensen, C L; Munson, A S; Steed, B; Rinella, M J

    2013-02-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), is among the primary causes of mature lodgepole pine, Pinus contorta variety latifolia mortality. Verbenone is the only antiaggregant semiochemical commercially available for reducing mountain pine beetle infestation of lodgepole pine. The success of verbenone treatments has varied greatly in previous studies because of differences in study duration, beetle population size, tree size, or other factors. To determine the ability of verbenone to protect lodgepole pine over long-term mountain pine beetle outbreaks, we applied verbenone treatments annually for 3 to 7 yr at five western United States sites. At one site, an outbreak did not develop; at two sites, verbenone reduced lodgepole pine mortality in medium and large diameter at breast height trees, and at the remaining two sites verbenone was ineffective at reducing beetle infestation. Verbenone reduced mountain pine beetle infestation of lodgepole pine trees in treated areas when populations built gradually or when outbreaks in surrounding untreated forests were of moderate severity. Verbenone did not protect trees when mountain pine beetle populations rapidly increase. PMID:23448035

  20. Severe White Pine Blister Rust Infection in Whitebark Pine Alters Mountain Pine Beetle (Coleoptera: Curculionidae) Attack Density, Emergence Rate, and Body Size.

    PubMed

    Dooley, Edith M; Six, Diana L

    2015-10-01

    Exotic tree pathogens can cause devastating ecological effects on forests that can be exacerbated when infections increase the likelihood of attack by insects. Current high rates of mortality of whitebark pine (Pinus albicaulis Engelm.) are due to white pine blister rust caused by the exotic fungus, Cronartium ribicola J.C. Fisch, and the native mountain pine beetle (Dendroctonus ponderosae Hopkins). These two mortality agents interact in whitebark pine; mountain pine beetle preferentially selects white pine blister rust-infected whitebark pine over healthy trees, and likelihood of attack has been observed to increase with infection severity. We examined attack and emergence rates, and size and sex ratio of mountain pine beetle in whitebark pines exhibiting varying white pine blister rust infection severities. Mountain pine beetle attack density was lowest on the most severely infected trees, but emergence rates and size of beetles from these trees were greater than those from uninfected and less severely infected trees. Low attack rates on severely infected whitebark pine may indicate these trees have lower defenses and that fewer beetle attacks are needed to kill them. Higher beetle emergence rates from severely infected trees may be due to low intraspecific competition resulting from low attack rates or differences in nutrient quality.

  1. Chemical similarity between historical and novel host plants promotes range and host expansion of the mountain pine beetle in a naïve host ecosystem.

    PubMed

    Erbilgin, Nadir; Ma, Cary; Whitehouse, Caroline; Shan, Bin; Najar, Ahmed; Evenden, Maya

    2014-02-01

    Host plant secondary chemistry can have cascading impacts on host and range expansion of herbivorous insect populations. We investigated the role of host secondary compounds on pheromone production by the mountain pine beetle (Dendroctonus ponderosae) (MPB) and beetle attraction in response to a historical (lodgepole pine, Pinus contorta var. latifolia) and a novel (jack pine, Pinus banksiana) hosts, as pheromones regulate the host colonization process. Beetles emit the same pheromones from both hosts, but more trans-verbenol, the primary aggregation pheromone, was emitted by female beetles on the novel host. The phloem of the novel host contains more α-pinene, a secondary compound that is the precursor for trans-verbenol production in beetle, than the historical host. Beetle-induced emission of 3-carene, another secondary compound found in both hosts, was also higher from the novel host. Field tests showed that the addition of 3-carene to the pheromone mixture mimicking the aggregation pheromones produced from the two host species increased beetle capture. We conclude that chemical similarity between historical and novel hosts has facilitated host expansion of MPB in jack pine forests through the exploitation of common host secondary compounds for pheromone production and aggregation on the hosts. Furthermore, broods emerging from the novel host were larger in terms of body size.

  2. Severe White Pine Blister Rust Infection in Whitebark Pine Alters Mountain Pine Beetle (Coleoptera: Curculionidae) Attack Density, Emergence Rate, and Body Size.

    PubMed

    Dooley, Edith M; Six, Diana L

    2015-10-01

    Exotic tree pathogens can cause devastating ecological effects on forests that can be exacerbated when infections increase the likelihood of attack by insects. Current high rates of mortality of whitebark pine (Pinus albicaulis Engelm.) are due to white pine blister rust caused by the exotic fungus, Cronartium ribicola J.C. Fisch, and the native mountain pine beetle (Dendroctonus ponderosae Hopkins). These two mortality agents interact in whitebark pine; mountain pine beetle preferentially selects white pine blister rust-infected whitebark pine over healthy trees, and likelihood of attack has been observed to increase with infection severity. We examined attack and emergence rates, and size and sex ratio of mountain pine beetle in whitebark pines exhibiting varying white pine blister rust infection severities. Mountain pine beetle attack density was lowest on the most severely infected trees, but emergence rates and size of beetles from these trees were greater than those from uninfected and less severely infected trees. Low attack rates on severely infected whitebark pine may indicate these trees have lower defenses and that fewer beetle attacks are needed to kill them. Higher beetle emergence rates from severely infected trees may be due to low intraspecific competition resulting from low attack rates or differences in nutrient quality. PMID:26314009

  3. Population densities and tree diameter effects associated with verbenone treatments to reduce mountain pine beetle-caused mortality of lodgepole pine.

    PubMed

    Progar, R A; Blackford, D C; Cluck, D R; Costello, S; Dunning, L B; Eager, T; Jorgensen, C L; Munson, A S; Steed, B; Rinella, M J

    2013-02-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae: Scolytinae), is among the primary causes of mature lodgepole pine, Pinus contorta variety latifolia mortality. Verbenone is the only antiaggregant semiochemical commercially available for reducing mountain pine beetle infestation of lodgepole pine. The success of verbenone treatments has varied greatly in previous studies because of differences in study duration, beetle population size, tree size, or other factors. To determine the ability of verbenone to protect lodgepole pine over long-term mountain pine beetle outbreaks, we applied verbenone treatments annually for 3 to 7 yr at five western United States sites. At one site, an outbreak did not develop; at two sites, verbenone reduced lodgepole pine mortality in medium and large diameter at breast height trees, and at the remaining two sites verbenone was ineffective at reducing beetle infestation. Verbenone reduced mountain pine beetle infestation of lodgepole pine trees in treated areas when populations built gradually or when outbreaks in surrounding untreated forests were of moderate severity. Verbenone did not protect trees when mountain pine beetle populations rapidly increase.

  4. Mountain Pine Beetle Dynamics and Reproductive Success in Post-Fire Lodgepole and Ponderosa Pine Forests in Northeastern Utah

    PubMed Central

    Lerch, Andrew P.; Pfammatter, Jesse A.

    2016-01-01

    Fire injury can increase tree susceptibility to some bark beetles (Curculionidae, Scolytinae), but whether wildfires can trigger outbreaks of species such as mountain pine beetle (Dendroctonus ponderosae Hopkins) is not well understood. We monitored 1173 lodgepole (Pinus contorta var. latifolia Doug.) and 599 ponderosa (Pinus ponderosa Doug. ex Law) pines for three years post-wildfire in the Uinta Mountains of northeastern Utah in an area with locally endemic mountain pine beetle. We examined how the degree and type of fire injury influenced beetle attacks, brood production, and subsequent tree mortality, and related these to beetle population changes over time. Mountain pine beetle population levels were high the first two post-fire years in lodgepole pine, and then declined. In ponderosa pine, populations declined each year after initial post-fire sampling. Compared to trees with strip or failed attacks, mass attacks occurred on trees with greater fire injury, in both species. Overall, a higher degree of damage to crowns and boles was associated with higher attack rates in ponderosa pines, but additional injury was more likely to decrease attack rates in lodgepole pines. In lodgepole pine, attacks were initially concentrated on fire-injured trees, but during subsequent years beetles attacked substantial numbers of uninjured trees. In ponderosa pine, attacks were primarily on injured trees each year, although these stands were more heavily burned and had few uninjured trees. In total, 46% of all lodgepole and 56% of ponderosa pines underwent some degree of attack. Adult brood emergence within caged bole sections decreased with increasing bole char in lodgepole pine but increased in ponderosa pine, however these relationships did not scale to whole trees. Mountain pine beetle populations in both tree species four years post-fire were substantially lower than the year after fire, and wildfire did not result in population outbreaks. PMID:27783632

  5. Disentangling Detoxification: Gene Expression Analysis of Feeding Mountain Pine Beetle Illuminates Molecular-Level Host Chemical Defense Detoxification Mechanisms

    PubMed Central

    Robert, Jeanne A.; Pitt, Caitlin; Bonnett, Tiffany R.; Yuen, Macaire M. S.; Keeling, Christopher I.; Bohlmann, Jörg; Huber, Dezene P. W.

    2013-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a native species of bark beetle (Coleoptera: Curculionidae) that caused unprecedented damage to the pine forests of British Columbia and other parts of western North America and is currently expanding its range into the boreal forests of central and eastern Canada and the USA. We conducted a large-scale gene expression analysis (RNA-seq) of mountain pine beetle male and female adults either starved or fed in male-female pairs for 24 hours on lodgepole pine host tree tissues. Our aim was to uncover transcripts involved in coniferophagous mountain pine beetle detoxification systems during early host colonization. Transcripts of members from several gene families significantly increased in insects fed on host tissue including: cytochromes P450, glucosyl transferases and glutathione S-transferases, esterases, and one ABC transporter. Other significantly increasing transcripts with potential roles in detoxification of host defenses included alcohol dehydrogenases and a group of unexpected transcripts whose products may play an, as yet, undiscovered role in host colonization by mountain pine beetle. PMID:24223726

  6. Fungal Volatiles Can Act as Carbon Sources and Semiochemicals to Mediate Interspecific Interactions Among Bark Beetle-Associated Fungal Symbionts

    PubMed Central

    Collignon, R. Maxwell; Klutsch, Jennifer G.; Kanekar, Sanat S.; Hussain, Altaf; Erbilgin, Nadir

    2016-01-01

    Mountain pine beetle (Dendroctonus ponderosae) has killed millions of hectares of pine forests in western North America. Beetle success is dependent upon a community of symbiotic fungi comprised of Grosmannia clavigera, Ophiostoma montium, and Leptographium longiclavatum. Factors regulating the dynamics of this community during pine infection are largely unknown. However, fungal volatile organic compounds (FVOCs) help shape fungal interactions in model and agricultural systems and thus may be important drivers of interactions among bark beetle-associated fungi. We investigated whether FVOCs can mediate interspecific interactions among mountain pine beetle’s fungal symbionts by affecting fungal growth and reproduction. Headspace volatiles were collected and identified to determine species-specific volatile profiles. Interspecific effects of volatiles on fungal growth and conidia production were assessed by pairing physically-separated fungal cultures grown either on a carbon-poor or -rich substrate, inside a shared-headspace environment. Fungal VOC profiles differed by species and influenced the growth and/or conidia production of the other species. Further, our results showed that FVOCs can be used as carbon sources for fungi developing on carbon-poor substrates. This is the first report demonstrating that FVOCs can drive interactions among bark beetle fungal symbionts, and thus are important factors in beetle attack success. PMID:27583519

  7. Disentangling detoxification: gene expression analysis of feeding mountain pine beetle illuminates molecular-level host chemical defense detoxification mechanisms.

    PubMed

    Robert, Jeanne A; Pitt, Caitlin; Bonnett, Tiffany R; Yuen, Macaire M S; Keeling, Christopher I; Bohlmann, Jörg; Huber, Dezene P W

    2013-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a native species of bark beetle (Coleoptera: Curculionidae) that caused unprecedented damage to the pine forests of British Columbia and other parts of western North America and is currently expanding its range into the boreal forests of central and eastern Canada and the USA. We conducted a large-scale gene expression analysis (RNA-seq) of mountain pine beetle male and female adults either starved or fed in male-female pairs for 24 hours on lodgepole pine host tree tissues. Our aim was to uncover transcripts involved in coniferophagous mountain pine beetle detoxification systems during early host colonization. Transcripts of members from several gene families significantly increased in insects fed on host tissue including: cytochromes P450, glucosyl transferases and glutathione S-transferases, esterases, and one ABC transporter. Other significantly increasing transcripts with potential roles in detoxification of host defenses included alcohol dehydrogenases and a group of unexpected transcripts whose products may play an, as yet, undiscovered role in host colonization by mountain pine beetle.

  8. Comparing the impacts of mitigation and non-mitigation on mountain pine beetle populations.

    PubMed

    Coggins, Sam B; Coops, Nicholas C; Wulder, Michael A; Bater, Christopher W; Ortlepp, Stephanie M

    2011-01-01

    Mountain pine beetles, Dendroctonus ponderosae (Hopkins) attack and can ultimately kill individuals and groups of pine trees, specifically lodgepole pine (Pinus contorta Dougl. ex. Loud var. latifolia Engl.). In British Columbia, beetle attack has increased from 164 000 ha in 1999 to over 13 million ha in 2008. Mitigation efforts can play a key role in addressing the impact beetle infestations can have on the forested landscape. In this research, the impact of mitigation on a mountain pine beetle infestation is examined within a network of 28 research plots where sanitation harvesting was completed (10 mitigated plots) and not completed (18 unmitigated plots). Three forest stand level modelling scenarios which predict the number of attacked trees, based on current infestation within the plots, were utilized to compare the differences between mitigated and non-mitigated plots. In the first scenario in the non-mitigated plots, 125 trees were infested after 10 years, while in the mitigated plots no trees were infested in the same time period. The second scenario indicates the level of mitigation required to suppress beetle infestations where the proportion of mitigated trees was calculated for each plot by counting the residual attack and the number of mitigated trees. The average mitigation rate over all plots of 43% (range 0-100%) is not sufficient to provide control. In the non-mitigated plots, the average population expansion rate was 5 (range of 0-18) which requires a detection accuracy of 74% to reliably detect infestation. The third scenario estimated the length of time required for ongoing detection, monitoring, and mitigation to bring an infestation under control. If mitigation efforts were maintained at the current rate of 43%, the beetle population would not be adequately controlled. However, when aided by continued detection and monitoring of attacked trees, mitigation rates greater than 50% are sufficient to control infestations, especially with

  9. Comparing the impacts of mitigation and non-mitigation on mountain pine beetle populations.

    PubMed

    Coggins, Sam B; Coops, Nicholas C; Wulder, Michael A; Bater, Christopher W; Ortlepp, Stephanie M

    2011-01-01

    Mountain pine beetles, Dendroctonus ponderosae (Hopkins) attack and can ultimately kill individuals and groups of pine trees, specifically lodgepole pine (Pinus contorta Dougl. ex. Loud var. latifolia Engl.). In British Columbia, beetle attack has increased from 164 000 ha in 1999 to over 13 million ha in 2008. Mitigation efforts can play a key role in addressing the impact beetle infestations can have on the forested landscape. In this research, the impact of mitigation on a mountain pine beetle infestation is examined within a network of 28 research plots where sanitation harvesting was completed (10 mitigated plots) and not completed (18 unmitigated plots). Three forest stand level modelling scenarios which predict the number of attacked trees, based on current infestation within the plots, were utilized to compare the differences between mitigated and non-mitigated plots. In the first scenario in the non-mitigated plots, 125 trees were infested after 10 years, while in the mitigated plots no trees were infested in the same time period. The second scenario indicates the level of mitigation required to suppress beetle infestations where the proportion of mitigated trees was calculated for each plot by counting the residual attack and the number of mitigated trees. The average mitigation rate over all plots of 43% (range 0-100%) is not sufficient to provide control. In the non-mitigated plots, the average population expansion rate was 5 (range of 0-18) which requires a detection accuracy of 74% to reliably detect infestation. The third scenario estimated the length of time required for ongoing detection, monitoring, and mitigation to bring an infestation under control. If mitigation efforts were maintained at the current rate of 43%, the beetle population would not be adequately controlled. However, when aided by continued detection and monitoring of attacked trees, mitigation rates greater than 50% are sufficient to control infestations, especially with

  10. Effects of Bark Beetle Infestation on Secondary Organic Aerosol Precursors in the Western United States

    NASA Astrophysics Data System (ADS)

    Huff Hartz, K. E.; Amin, H.; Dodson, C.; Atkins, P. T.; Hallar, G.

    2009-12-01

    Bark beetles are a potentially destructive force in forest ecosytems; however, it is not known how insect attacks affect the atmosphere. Other insects, such as the weevil (Strophosoma melanogrammum) attacks on spruce trees in Denmark, have a significant local effect on monoterpene emissions. In fact, a single weevil induced a three-fold increase in monoterpene emission, and the response lasted for several weeks. Mountain pine bark beetles (Dendroctonus ponderosae) have infested the forests in the vicinity of Storm Peak Laboratory near Steamboat Springs, Colorado. Emissions were sampled from the headspace of bark at the trunk and from the tree branches in the canopy from bark beetle infested and healthy lodgepole pine (Pinus contorta var. latifolia) and Engelmann spruce (Picea engelmannii) trees. The emissions were collected onto scent traps, containing 110 mg of Porapak Q sorbent, using PAS-500 micro air samplers set to a 0.4 mL/min flow rate for two hours. After collection, the scent traps were spiked with a recovery standard, perdeutrated decane, and extracted with 1.5 mL hexanes (in three portions). The analytes in the extracts were separated and detected using gas chromatography/mass spectroscopy. The analytes were identified and quantified using calibration curves from authentic standards, and when authentic standards were not available, the NIST mass spectra library and Adams retention time indices were used. The samples from lodgepole pine trees suggest an enhancement in the 3-carene, beta-phellandrene, and estragole (methyl chavicol) emissions upon bark beetle infestation. The samples from the Engelmann spruce trees suggest an enhancement in the 1,4-cineole, p-cymene, and beta-phellandrene emissions upon bark beetle infestation. A shift in the type and the quantity of VOC emissions due to bark beetle infestation may lead increases in SOA from these forests, since potent SOA precursors are produced.

  11. The Classroom Animal: Flour Beetles.

    ERIC Educational Resources Information Center

    Kramer, David C.

    1988-01-01

    Describes the flour beetle, "Tribolium confusum," and its life cycle, habitat, culturing requirements, and some possible uses of this beetle as a classroom animal. Discusses what children could learn from flour beetles. Explains how to get rid of beetles found in foods at home. (CW)

  12. Molecular evidence of facultative intraguild predation by Monochamus titillator larvae (Coleoptera: Cerambycidae) on members of the southern pine beetle guild

    NASA Astrophysics Data System (ADS)

    Schoeller, Erich N.; Husseneder, Claudia; Allison, Jeremy D.

    2012-11-01

    The southern pine bark beetle guild (SPBG) is arguably the most destructive group of forest insects in the southeastern USA. This guild contains five species of bark beetles (Coleoptera: Curculionidae: Scolytinae): Dendroctonus frontalis, Dendroctonus terebrans, Ips avulsus, Ips calligraphus, and Ips grandicollis. A diverse community of illicit receivers is attracted to pheromones emitted by the SPBG, including the woodborers Monochamus carolinensis and Monochamus titillator (Coleoptera: Cerambycidae). These woodborers have been traditionally classified as resource competitors; however, laboratory assays suggest that larval M. carolinensis may be facultative intraguild predators of SPBG larvae. This study used polymerase chain reaction (PCR)-based molecular gut content analyses to characterize subcortical interactions between M. titillator and members of the SPBG. The half-lives of SPBG DNA were estimated in the laboratory prior to examining these interactions in the field. A total of 271 field-collected M. titillator larvae were analyzed and 26 (9.6 %) tested positive for DNA of members of the SPBG. Of these larvae, 25 (96.2 %) tested positive for I. grandicollis and one (3.8 %) for I. calligraphus. Failure to detect D. terebrans and D. frontalis was likely due to their absence in the field. I. avulsus was present, but primers developed using adult tissues failed to amplify larval tissue. Results from this study support the hypothesis that larval Monochamus spp. are facultative intraguild predators of bark beetle larvae. Additionally, this study demonstrates the capabilities of PCR in elucidating the interactions of cryptic forest insects and provides a tool to better understand mechanisms driving southern pine beetle guild population fluctuations.

  13. Mountain pine beetle and forest carbon feedback to climate change.

    PubMed

    Kurz, W A; Dymond, C C; Stinson, G; Rampley, G J; Neilson, E T; Carroll, A L; Ebata, T; Safranyik, L

    2008-04-24

    The mountain pine beetle (Dendroctonus ponderosae Hopkins, Coleoptera: Curculionidae, Scolytinae) is a native insect of the pine forests of western North America, and its populations periodically erupt into large-scale outbreaks. During outbreaks, the resulting widespread tree mortality reduces forest carbon uptake and increases future emissions from the decay of killed trees. The impacts of insects on forest carbon dynamics, however, are generally ignored in large-scale modelling analyses. The current outbreak in British Columbia, Canada, is an order of magnitude larger in area and severity than all previous recorded outbreaks. Here we estimate that the cumulative impact of the beetle outbreak in the affected region during 2000-2020 will be 270 megatonnes (Mt) carbon (or 36 g carbon m(-2) yr(-1) on average over 374,000 km2 of forest). This impact converted the forest from a small net carbon sink to a large net carbon source both during and immediately after the outbreak. In the worst year, the impacts resulting from the beetle outbreak in British Columbia were equivalent to approximately 75% of the average annual direct forest fire emissions from all of Canada during 1959-1999. The resulting reduction in net primary production was of similar magnitude to increases observed during the 1980s and 1990s as a result of global change. Climate change has contributed to the unprecedented extent and severity of this outbreak. Insect outbreaks such as this represent an important mechanism by which climate change may undermine the ability of northern forests to take up and store atmospheric carbon, and such impacts should be accounted for in large-scale modelling analyses.

  14. Mountain pine beetles colonizing historical and naive host trees are associated with a bacterial community highly enriched in genes contributing to terpene metabolism.

    PubMed

    Adams, Aaron S; Aylward, Frank O; Adams, Sandye M; Erbilgin, Nadir; Aukema, Brian H; Currie, Cameron R; Suen, Garret; Raffa, Kenneth F

    2013-06-01

    The mountain pine beetle, Dendroctonus ponderosae, is a subcortical herbivore native to western North America that can kill healthy conifers by overcoming host tree defenses, which consist largely of high terpene concentrations. The mechanisms by which these beetles contend with toxic compounds are not well understood. Here, we explore a component of the hypothesis that beetle-associated bacterial symbionts contribute to the ability of D. ponderosae to overcome tree defenses by assisting with terpene detoxification. Such symbionts may facilitate host tree transitions during range expansions currently being driven by climate change. For example, this insect has recently breached the historical geophysical barrier of the Canadian Rocky Mountains, providing access to näive tree hosts and unprecedented connectivity to eastern forests. We use culture-independent techniques to describe the bacterial community associated with D. ponderosae beetles and their galleries from their historical host, Pinus contorta, and their more recent host, hybrid P. contorta-Pinus banksiana. We show that these communities are enriched with genes involved in terpene degradation compared with other plant biomass-processing microbial communities. These pine beetle microbial communities are dominated by members of the genera Pseudomonas, Rahnella, Serratia, and Burkholderia, and the majority of genes involved in terpene degradation belong to these genera. Our work provides the first metagenome of bacterial communities associated with a bark beetle and is consistent with a potential microbial contribution to detoxification of tree defenses needed to survive the subcortical environment. PMID:23542624

  15. Mountain Pine Beetles Colonizing Historical and Naïve Host Trees Are Associated with a Bacterial Community Highly Enriched in Genes Contributing to Terpene Metabolism

    PubMed Central

    Adams, Aaron S.; Aylward, Frank O.; Adams, Sandye M.; Erbilgin, Nadir; Aukema, Brian H.; Currie, Cameron R.

    2013-01-01

    The mountain pine beetle, Dendroctonus ponderosae, is a subcortical herbivore native to western North America that can kill healthy conifers by overcoming host tree defenses, which consist largely of high terpene concentrations. The mechanisms by which these beetles contend with toxic compounds are not well understood. Here, we explore a component of the hypothesis that beetle-associated bacterial symbionts contribute to the ability of D. ponderosae to overcome tree defenses by assisting with terpene detoxification. Such symbionts may facilitate host tree transitions during range expansions currently being driven by climate change. For example, this insect has recently breached the historical geophysical barrier of the Canadian Rocky Mountains, providing access to näive tree hosts and unprecedented connectivity to eastern forests. We use culture-independent techniques to describe the bacterial community associated with D. ponderosae beetles and their galleries from their historical host, Pinus contorta, and their more recent host, hybrid P. contorta-Pinus banksiana. We show that these communities are enriched with genes involved in terpene degradation compared with other plant biomass-processing microbial communities. These pine beetle microbial communities are dominated by members of the genera Pseudomonas, Rahnella, Serratia, and Burkholderia, and the majority of genes involved in terpene degradation belong to these genera. Our work provides the first metagenome of bacterial communities associated with a bark beetle and is consistent with a potential microbial contribution to detoxification of tree defenses needed to survive the subcortical environment. PMID:23542624

  16. Mountain pine beetles colonizing historical and naive host trees are associated with a bacterial community highly enriched in genes contributing to terpene metabolism.

    PubMed

    Adams, Aaron S; Aylward, Frank O; Adams, Sandye M; Erbilgin, Nadir; Aukema, Brian H; Currie, Cameron R; Suen, Garret; Raffa, Kenneth F

    2013-06-01

    The mountain pine beetle, Dendroctonus ponderosae, is a subcortical herbivore native to western North America that can kill healthy conifers by overcoming host tree defenses, which consist largely of high terpene concentrations. The mechanisms by which these beetles contend with toxic compounds are not well understood. Here, we explore a component of the hypothesis that beetle-associated bacterial symbionts contribute to the ability of D. ponderosae to overcome tree defenses by assisting with terpene detoxification. Such symbionts may facilitate host tree transitions during range expansions currently being driven by climate change. For example, this insect has recently breached the historical geophysical barrier of the Canadian Rocky Mountains, providing access to näive tree hosts and unprecedented connectivity to eastern forests. We use culture-independent techniques to describe the bacterial community associated with D. ponderosae beetles and their galleries from their historical host, Pinus contorta, and their more recent host, hybrid P. contorta-Pinus banksiana. We show that these communities are enriched with genes involved in terpene degradation compared with other plant biomass-processing microbial communities. These pine beetle microbial communities are dominated by members of the genera Pseudomonas, Rahnella, Serratia, and Burkholderia, and the majority of genes involved in terpene degradation belong to these genera. Our work provides the first metagenome of bacterial communities associated with a bark beetle and is consistent with a potential microbial contribution to detoxification of tree defenses needed to survive the subcortical environment.

  17. Western Pine Beetle Populations in Arizona and California Differ in the Composition of Their Aggregation Pheromones.

    PubMed

    Pureswaran, Deepa S; Hofstetter, Richard W; Sullivan, Brian T; Grady, Amanda M; Brownie, Cavell

    2016-05-01

    We compared pheromone production and response for populations of western pine beetle, Dendroctonus brevicomis LeConte, from sites in northern Arizona and northern California. Volatiles were collected from individuals of both sexes that had mined as a pair in a Pinus ponderosa log for 1 d, and they were subsequently analyzed by gas chromatography coupled to mass-spectrometry. Principal component analysis of quantities of Dendroctonus pheromone components indicated strong site-associated clustering of blend composition for females but not males. Much of the clustering in females evidently was due to differences in the production of endo- and exo-brevicomin, which occurred in average ratios of 0.1:1 and 19:1 for populations in the California and Arizona sites, respectively. In the California site, exo- was better than endo-brevicomin in enhancing trap catches of both sexes to lures containing the host-tree odor α-pinene and the male-produced aggregation pheromone component frontalin. In an identical test in the Arizona site, endo- was a better adjuvant than exo-brevicomin for male attraction, whereas females did not show a significant preference. At neither location were the isomers antagonistic to one another in activity. Thus, one aggregation pheromone has apparently diverged between these populations, concurrent with published evidence that D. brevicomis on either side of the Great Basin are genetically distinct and are possibly different species. Furthermore, production of and response to the isomers of brevicomin by flying Dendroctonus frontalis Zimmermann in the Arizona site were similar to those of sympatric D. brevicomis. This interspecific signal overlap is likely sustainable since joint species mass-attacks may assist both species in overcoming host defenses, thereby increasing host availability.

  18. Western Pine Beetle Populations in Arizona and California Differ in the Composition of Their Aggregation Pheromones.

    PubMed

    Pureswaran, Deepa S; Hofstetter, Richard W; Sullivan, Brian T; Grady, Amanda M; Brownie, Cavell

    2016-05-01

    We compared pheromone production and response for populations of western pine beetle, Dendroctonus brevicomis LeConte, from sites in northern Arizona and northern California. Volatiles were collected from individuals of both sexes that had mined as a pair in a Pinus ponderosa log for 1 d, and they were subsequently analyzed by gas chromatography coupled to mass-spectrometry. Principal component analysis of quantities of Dendroctonus pheromone components indicated strong site-associated clustering of blend composition for females but not males. Much of the clustering in females evidently was due to differences in the production of endo- and exo-brevicomin, which occurred in average ratios of 0.1:1 and 19:1 for populations in the California and Arizona sites, respectively. In the California site, exo- was better than endo-brevicomin in enhancing trap catches of both sexes to lures containing the host-tree odor α-pinene and the male-produced aggregation pheromone component frontalin. In an identical test in the Arizona site, endo- was a better adjuvant than exo-brevicomin for male attraction, whereas females did not show a significant preference. At neither location were the isomers antagonistic to one another in activity. Thus, one aggregation pheromone has apparently diverged between these populations, concurrent with published evidence that D. brevicomis on either side of the Great Basin are genetically distinct and are possibly different species. Furthermore, production of and response to the isomers of brevicomin by flying Dendroctonus frontalis Zimmermann in the Arizona site were similar to those of sympatric D. brevicomis. This interspecific signal overlap is likely sustainable since joint species mass-attacks may assist both species in overcoming host defenses, thereby increasing host availability. PMID:27125814

  19. Mountain Pine Beetles Use Volatile Cues to Locate Host Limber Pine and Avoid Non-Host Great Basin Bristlecone Pine.

    PubMed

    Gray, Curtis A; Runyon, Justin B; Jenkins, Michael J; Giunta, Andrew D

    2015-01-01

    The tree-killing mountain pine beetle (Dendroctonus ponderosae Hopkins) is an important disturbance agent of western North American forests and recent outbreaks have affected tens of millions of hectares of trees. Most western North American pines (Pinus spp.) are hosts and are successfully attacked by mountain pine beetles whereas a handful of pine species are not suitable hosts and are rarely attacked. How pioneering females locate host trees is not well understood, with prevailing theory involving random landings and/or visual cues. Here we show that female mountain pine beetles orient toward volatile organic compounds (VOCs) from host limber pine (Pinus flexilis James) and away from VOCs of non-host Great Basin bristlecone pine (Pinus longaeva Bailey) in a Y-tube olfactometer. When presented with VOCs of both trees, females overwhelmingly choose limber pine over Great Basin bristlecone pine. Analysis of VOCs collected from co-occurring limber and Great Basin bristlecone pine trees revealed only a few quantitative differences. Noticeable differences included the monoterpenes 3-carene and D-limonene which were produced in greater amounts by host limber pine. We found no evidence that 3-carene is important for beetles when selecting trees, it was not attractive alone and its addition to Great Basin bristlecone pine VOCs did not alter female selection. However, addition of D-limonene to Great Basin bristlecone pine VOCs disrupted the ability of beetles to distinguish between tree species. When presented alone, D-limonene did not affect behavior, suggesting that the response is mediated by multiple compounds. A better understanding of host selection by mountain pine beetles could improve strategies for managing this important forest insect. Moreover, elucidating how Great Basin bristlecone pine escapes attack by mountain pine beetles could provide insight into mechanisms underlying the incredible longevity of this tree species.

  20. Mountain Pine Beetles Use Volatile Cues to Locate Host Limber Pine and Avoid Non-Host Great Basin Bristlecone Pine

    PubMed Central

    Gray, Curtis A.; Runyon, Justin B.; Jenkins, Michael J.; Giunta, Andrew D.

    2015-01-01

    The tree-killing mountain pine beetle (Dendroctonus ponderosae Hopkins) is an important disturbance agent of western North American forests and recent outbreaks have affected tens of millions of hectares of trees. Most western North American pines (Pinus spp.) are hosts and are successfully attacked by mountain pine beetles whereas a handful of pine species are not suitable hosts and are rarely attacked. How pioneering females locate host trees is not well understood, with prevailing theory involving random landings and/or visual cues. Here we show that female mountain pine beetles orient toward volatile organic compounds (VOCs) from host limber pine (Pinus flexilis James) and away from VOCs of non-host Great Basin bristlecone pine (Pinus longaeva Bailey) in a Y-tube olfactometer. When presented with VOCs of both trees, females overwhelmingly choose limber pine over Great Basin bristlecone pine. Analysis of VOCs collected from co-occurring limber and Great Basin bristlecone pine trees revealed only a few quantitative differences. Noticeable differences included the monoterpenes 3-carene and D-limonene which were produced in greater amounts by host limber pine. We found no evidence that 3-carene is important for beetles when selecting trees, it was not attractive alone and its addition to Great Basin bristlecone pine VOCs did not alter female selection. However, addition of D-limonene to Great Basin bristlecone pine VOCs disrupted the ability of beetles to distinguish between tree species. When presented alone, D-limonene did not affect behavior, suggesting that the response is mediated by multiple compounds. A better understanding of host selection by mountain pine beetles could improve strategies for managing this important forest insect. Moreover, elucidating how Great Basin bristlecone pine escapes attack by mountain pine beetles could provide insight into mechanisms underlying the incredible longevity of this tree species. PMID:26332317

  1. A Tale of Two Forests: Simulating Contrasting Lodgepole Pine and Spruce Forest Water and Carbon Fluxes Following Mortality from Bark Beetles

    NASA Astrophysics Data System (ADS)

    Ewers, B. E.; Peckham, S. D.; Mackay, D. S.; Pendall, E.; Frank, J. M.; Massman, W. J.; Reed, D. E.; Borkhuu, B.

    2014-12-01

    In recent decades, bark beetle infestation in western North America has reached epidemic levels. The resulting widespread forest mortality may have profound effects on present and future water and carbon cycling with potential negative consequences to a region that relies on water from montane and subalpine watersheds. We simulated stand-level ecosystem fluxes of water and carbon at two bark beetle-attacked conifer forests in southeast Wyoming, USA. The lower elevation site dominated by lodgepole pine (Pinus contorta) was attacked by mountain pine beetle (Dendroctonus ponderosae) during 2008-2010. The high elevation Engelmann spruce (Picea engelmannii) dominated site was attacked by the spruce beetle (Dendroctonus rufipennis) during roughly the same time period. Both beetle infestations resulted in >60% canopy mortality in the footprint of eddy covariance towers located at each site. However, carbon and water fluxes responses to mortality depended on the forest type. Using data collected at the sites, we scaled simulated plant hydraulic conductivity by either percent canopy mortality or loss of live tree basal area during infestation. We also simulated a case of no beetle attack. At the lodgepole site, the no-beetle model best fit the data and showed no significant change in growing season carbon flux and a 15% decrease in evapotranspiration (ET). However, at the spruce site, the simulation that tracked canopy loss agreed best with observations: carbon flux decreased by 72% and ET decreased by 31%. In the lodgepole stand, simulated soil water content agreed with spatially distributed measurements that were weighted to reflect overall mortality in the tower footprint. Although these two forest ecosystems are only 20 km apart, separated by less than 300m in elevation, and have been impacted by similar mortality agents, the associated changes in carbon and water cycling are significantly different. Beetle effects on hydrologic cycling were greatest at high elevation

  2. Assessing Impacts of Mountain Pine Beetle on Forest Stand Structure in Fraser Experimental Forest: Mapping Forest Characteristics Using Spatial Analyses with Landsat Imagery to Support Management Response Strategies and Restoration Efforts in Colorado Mixed-Conifer Forests

    NASA Astrophysics Data System (ADS)

    Favors, J. E.; Burnett, J.; Chignell, S.; Groy, K.; Luizza, M.; Zawacki, W.

    2012-12-01

    Mountain pine beetle (Dendroctonus ponderosae) infestations have reached epidemic proportions across the western United States, with the Colorado Rockies enduring extensive damage. Aerial detection surveys have been effective in measuring rate of spread but have no way of accurately determining how much of the forest over story is affected by beetle mortality. Understanding this impact on forest structure and composition holds great importance for land managers, researchers and community members alike. Using Boosted Regression Tree modeling, Landsat 5 imagery and ancillary datasets, the goal of this project was to more accurately model forest land cover in Fraser Experimental Forest to assist in quantifying beetle mortality across the landscape. Field validation methods included assessment of over 100 plots stratified across the study site and model recalibration to achieve accuracy >80%. Collaborative efforts with local organizations included the U.S. Geological Survey, USDA Forest Service and Colorado State University.

  3. Diversity and decay ability of basidiomycetes isolated from lodgepole pines killed by the mountain pine beetle.

    PubMed

    Son, E; Kim, J-J; Lim, Y W; Au-Yeung, T T; Yang, C Y H; Breuil, C

    2011-01-01

    When lodgepole pines (Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson) that are killed by the mountain pine beetle (Dendroctonus ponderosae) and its fungal associates are not harvested, fungal decay can affect wood and fibre properties. Ophiostomatoids stain sapwood but do not affect the structural properties of wood. In contrast, white or brown decay basidiomycetes degrade wood. We isolated both staining and decay fungi from 300 lodgepole pine trees killed by mountain pine beetle at green, red, and grey stages at 10 sites across British Columbia. We retained 224 basidiomycete isolates that we classified into 34 species using morphological and physiological characteristics and rDNA large subunit sequences. The number of basidiomycete species varied from 4 to 14 species per site. We assessed the ability of these fungi to degrade both pine sapwood and heartwood using the soil jar decay test. The highest wood mass losses for both sapwood and heartwood were measured for the brown rot species Fomitopsis pinicola and the white rot Metulodontia and Ganoderma species. The sap rot species Trichaptum abietinum was more damaging for sapwood than for heartwood. A number of species caused more than 50% wood mass losses after 12 weeks at room temperature, suggesting that beetle-killed trees can rapidly lose market value due to degradation of wood structural components. PMID:21217795

  4. Mountain Pine Beetle Host Selection Between Lodgepole and Ponderosa Pines in the Southern Rocky Mountains.

    PubMed

    West, Daniel R; Briggs, Jennifer S; Jacobi, William R; Negrón, José F

    2016-02-01

    Recent evidence of range expansion and host transition by mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) has suggested that MPB may not primarily breed in their natal host, but will switch hosts to an alternate tree species. As MPB populations expanded in lodgepole pine forests in the southern Rocky Mountains, we investigated the potential for movement into adjacent ponderosa pine forests. We conducted field and laboratory experiments to evaluate four aspects of MPB population dynamics and host selection behavior in the two hosts: emergence timing, sex ratios, host choice, and reproductive success. We found that peak MPB emergence from both hosts occurred simultaneously between late July and early August, and the sex ratio of emerging beetles did not differ between hosts. In two direct tests of MPB host selection, we identified a strong preference by MPB for ponderosa versus lodgepole pine. At field sites, we captured naturally emerging beetles from both natal hosts in choice arenas containing logs of both species. In the laboratory, we offered sections of bark and phloem from both species to individual insects in bioassays. In both tests, insects infested ponderosa over lodgepole pine at a ratio of almost 2:1, regardless of natal host species. Reproductive success (offspring/female) was similar in colonized logs of both hosts. Overall, our findings suggest that MPB may exhibit equally high rates of infestation and fecundity in an alternate host under favorable conditions. PMID:26546596

  5. Draft Genome of the Scarab Beetle Oryctes borbonicus on La Réunion Island.

    PubMed

    Meyer, Jan M; Markov, Gabriel V; Baskaran, Praveen; Herrmann, Matthias; Sommer, Ralf J; Rödelsperger, Christian

    2016-01-01

    Beetles represent the largest insect order and they display extreme morphological, ecological and behavioral diversity, which makes them ideal models for evolutionary studies. Here, we present the draft genome of the scarab beetle Oryctes borbonicus, which has a more basal phylogenetic position than the two previously sequenced pest species Tribolium castaneum and Dendroctonus ponderosae providing the potential for sequence polarization. Oryctes borbonicus is endemic to La Réunion, an island located in the Indian Ocean, and is the host of the nematode Pristionchus pacificus, a well-established model organism for integrative evolutionary biology. At 518 Mb, the O. borbonicus genome is substantially larger and encodes more genes than T. castaneum and D. ponderosae We found that only 25% of the predicted genes of O. borbonicus are conserved as single copy genes across the nine investigated insect genomes, suggesting substantial gene turnover within insects. Even within beetles, up to 21% of genes are restricted to only one species, whereas most other genes have undergone lineage-specific duplications and losses. We illustrate lineage-specific duplications using detailed phylogenetic analysis of two gene families. This study serves as a reference point for insect/coleopteran genomics, although its original motivation was to find evidence for potential horizontal gene transfer (HGT) between O. borbonicus and P. pacificus The latter was previously shown to be the recipient of multiple horizontally transferred genes including some genes from insect donors. However, our study failed to provide any clear evidence for additional HGTs between the two species. PMID:27289092

  6. Ecohydrology of an Outbreak: Impacts of vegetation pattern and landscape structure on mountain pine beetle disturbance

    NASA Astrophysics Data System (ADS)

    Kaiser, K.; McGlynn, B. L.; Emanuel, R. E.; Nippgen, F.; Mallard, J. M.

    2011-12-01

    Watershed ecohydrology considers runoff generation and streamflow as a function of vegetation pattern and landscape structure. The hydrologic implications of vegetation disturbance depend on the spatial extent and pattern of change on this ecohydrologic template. Here we investigate this intersection with a focus on a recent mountain pine beetle (Dendroctonus ponderosae) epidemic that is increasingly affecting areas in the Rocky Mountains. Our research area was the highly instrumented Tenderfoot Creek Experimental Forest (TCEF), Montana, USA. We used LiDAR vegetation structure data to isolate treed QuickBird pixels for subsequent classification. We calibrated QuickBird remote sensing imagery with leaf level measures by developing a spectral library for TCEF vegetation. The spectral library was used to determine which vegetation indices were optimal for differentiating between stages of infestation; thereby maximizing the information obtained from the QuickBird image. These indices were applied to the QuickBird imagery to establish baseline mortality, and the extent and magnitude of infestation across the watershed. In addition, we calculated LiDAR based topography and vegetation structure indices for joint topographic, vegetation, and disturbance analyses. We seek to determine which forest stands are most susceptible to beetle infestation, and how these infestation patterns are related to hydrologic, topographic, and forest ecosystem compositional characteristics. Our efforts to monitor vegetation mortality across space and time provide a context for assessing the drivers of mountain pine beetle infestation and how outbreak patterns may affect watershed ecohydrology via altered energy, water, and biogeochemical cycles.

  7. Draft Genome of the Scarab Beetle Oryctes borbonicus on La Réunion Island.

    PubMed

    Meyer, Jan M; Markov, Gabriel V; Baskaran, Praveen; Herrmann, Matthias; Sommer, Ralf J; Rödelsperger, Christian

    2016-07-12

    Beetles represent the largest insect order and they display extreme morphological, ecological and behavioral diversity, which makes them ideal models for evolutionary studies. Here, we present the draft genome of the scarab beetle Oryctes borbonicus, which has a more basal phylogenetic position than the two previously sequenced pest species Tribolium castaneum and Dendroctonus ponderosae providing the potential for sequence polarization. Oryctes borbonicus is endemic to La Réunion, an island located in the Indian Ocean, and is the host of the nematode Pristionchus pacificus, a well-established model organism for integrative evolutionary biology. At 518 Mb, the O. borbonicus genome is substantially larger and encodes more genes than T. castaneum and D. ponderosae We found that only 25% of the predicted genes of O. borbonicus are conserved as single copy genes across the nine investigated insect genomes, suggesting substantial gene turnover within insects. Even within beetles, up to 21% of genes are restricted to only one species, whereas most other genes have undergone lineage-specific duplications and losses. We illustrate lineage-specific duplications using detailed phylogenetic analysis of two gene families. This study serves as a reference point for insect/coleopteran genomics, although its original motivation was to find evidence for potential horizontal gene transfer (HGT) between O. borbonicus and P. pacificus The latter was previously shown to be the recipient of multiple horizontally transferred genes including some genes from insect donors. However, our study failed to provide any clear evidence for additional HGTs between the two species.

  8. Mountain Pine Beetle Host Selection Between Lodgepole and Ponderosa Pines in the Southern Rocky Mountains.

    PubMed

    West, Daniel R; Briggs, Jennifer S; Jacobi, William R; Negrón, José F

    2016-02-01

    Recent evidence of range expansion and host transition by mountain pine beetle (Dendroctonus ponderosae Hopkins; MPB) has suggested that MPB may not primarily breed in their natal host, but will switch hosts to an alternate tree species. As MPB populations expanded in lodgepole pine forests in the southern Rocky Mountains, we investigated the potential for movement into adjacent ponderosa pine forests. We conducted field and laboratory experiments to evaluate four aspects of MPB population dynamics and host selection behavior in the two hosts: emergence timing, sex ratios, host choice, and reproductive success. We found that peak MPB emergence from both hosts occurred simultaneously between late July and early August, and the sex ratio of emerging beetles did not differ between hosts. In two direct tests of MPB host selection, we identified a strong preference by MPB for ponderosa versus lodgepole pine. At field sites, we captured naturally emerging beetles from both natal hosts in choice arenas containing logs of both species. In the laboratory, we offered sections of bark and phloem from both species to individual insects in bioassays. In both tests, insects infested ponderosa over lodgepole pine at a ratio of almost 2:1, regardless of natal host species. Reproductive success (offspring/female) was similar in colonized logs of both hosts. Overall, our findings suggest that MPB may exhibit equally high rates of infestation and fecundity in an alternate host under favorable conditions.

  9. Draft Genome of the Scarab Beetle Oryctes borbonicus on La Réunion Island

    PubMed Central

    Meyer, Jan M.; Markov, Gabriel V.; Baskaran, Praveen; Herrmann, Matthias; Sommer, Ralf J.; Rödelsperger, Christian

    2016-01-01

    Beetles represent the largest insect order and they display extreme morphological, ecological and behavioral diversity, which makes them ideal models for evolutionary studies. Here, we present the draft genome of the scarab beetle Oryctes borbonicus, which has a more basal phylogenetic position than the two previously sequenced pest species Tribolium castaneum and Dendroctonus ponderosae providing the potential for sequence polarization. Oryctes borbonicus is endemic to La Réunion, an island located in the Indian Ocean, and is the host of the nematode Pristionchus pacificus, a well-established model organism for integrative evolutionary biology. At 518 Mb, the O. borbonicus genome is substantially larger and encodes more genes than T. castaneum and D. ponderosae. We found that only 25% of the predicted genes of O. borbonicus are conserved as single copy genes across the nine investigated insect genomes, suggesting substantial gene turnover within insects. Even within beetles, up to 21% of genes are restricted to only one species, whereas most other genes have undergone lineage-specific duplications and losses. We illustrate lineage-specific duplications using detailed phylogenetic analysis of two gene families. This study serves as a reference point for insect/coleopteran genomics, although its original motivation was to find evidence for potential horizontal gene transfer (HGT) between O. borbonicus and P. pacificus. The latter was previously shown to be the recipient of multiple horizontally transferred genes including some genes from insect donors. However, our study failed to provide any clear evidence for additional HGTs between the two species. PMID:27289092

  10. Temperature extremes, density dependence, and southern pine beetle (Coleoptera: Curculionidae) population dynamics in east Texas.

    PubMed

    Friedenberg, Nicholas A; Sarkar, Sudipta; Kouchoukos, Nicholas; Billings, Ronald F; Ayres, Matthew P

    2008-06-01

    Previous studies of the southern pine beetle, Dendroctonus frontalis Zimm., established that its population in east Texas responds to a delayed density-dependent process, whereas no clear role of climate has been determined. We tested two biological hypotheses for the influence of extreme temperatures on annual southern pine beetle population growth in the context of four alternative hypotheses for density-dependent population regulation. The significance of climate variables and their interaction with population regulation depended on the model of density dependence. The best model included both direct and delayed density dependence of a cubic rather than linear form. Population growth declined with the number of days exceeding 32 degrees C, temperatures previously reported to reduce brood survival. Density dependence also changed with the number of hot days. Growth was highest in years with average minimum winter temperatures. Severely cold winters may reduce survival, whereas warm winters may reduce the efficiency of spring infestation formation. Whereas most previous studies have incorporated climate as an additive effect on growth, we found that the form of delayed density dependence changed with the number of days >32 degrees C. The interaction between temperature and regulation, a potentially common phenomenon in ecology, may explain why southern pine beetle outbreaks do not occur at perfectly regular intervals. Factors other than climate, such as forest management and direct suppression, may have contributed significantly to the timing, severity, and eventual cessation of outbreaks since the mid-1950s.

  11. Diversity and decay ability of basidiomycetes isolated from lodgepole pines killed by the mountain pine beetle.

    PubMed

    Son, E; Kim, J-J; Lim, Y W; Au-Yeung, T T; Yang, C Y H; Breuil, C

    2011-01-01

    When lodgepole pines (Pinus contorta Douglas ex Louden var. latifolia Engelm. ex S. Watson) that are killed by the mountain pine beetle (Dendroctonus ponderosae) and its fungal associates are not harvested, fungal decay can affect wood and fibre properties. Ophiostomatoids stain sapwood but do not affect the structural properties of wood. In contrast, white or brown decay basidiomycetes degrade wood. We isolated both staining and decay fungi from 300 lodgepole pine trees killed by mountain pine beetle at green, red, and grey stages at 10 sites across British Columbia. We retained 224 basidiomycete isolates that we classified into 34 species using morphological and physiological characteristics and rDNA large subunit sequences. The number of basidiomycete species varied from 4 to 14 species per site. We assessed the ability of these fungi to degrade both pine sapwood and heartwood using the soil jar decay test. The highest wood mass losses for both sapwood and heartwood were measured for the brown rot species Fomitopsis pinicola and the white rot Metulodontia and Ganoderma species. The sap rot species Trichaptum abietinum was more damaging for sapwood than for heartwood. A number of species caused more than 50% wood mass losses after 12 weeks at room temperature, suggesting that beetle-killed trees can rapidly lose market value due to degradation of wood structural components.

  12. Ectomycorrhizal fungi mediate indirect effects of a bark beetle outbreak on secondary chemistry and establishment of pine seedlings.

    PubMed

    Karst, Justine; Erbilgin, Nadir; Pec, Gregory J; Cigan, Paul W; Najar, Ahmed; Simard, Suzanne W; Cahill, James F

    2015-11-01

    Dendroctonus ponderosae has killed millions of Pinus contorta in western North America with subsequent effects on stand conditions, including changes in light intensity, needle deposition, and the composition of fungal community mutualists, namely ectomycorrhizal fungi. It is unknown whether these changes in stand conditions will have cascading consequences for the next generation of pine seedlings. To test for transgenerational cascades on pine seedlings, we tested the effects of fungal inoculum origin (beetle-killed or undisturbed stands), light intensity and litter (origin and presence) on seedling secondary chemistry and growth in a glasshouse. We also tracked survival of seedlings over two growing seasons in the same stands from which fungi and litter were collected. Fungal communities differed by inoculum origin. Seedlings grown with fungi collected from beetle-killed stands had lower monoterpene concentrations and fewer monoterpene compounds present compared with seedlings grown with fungi collected from undisturbed stands. Litter affected neither monoterpenes nor seedling growth. Seedling survival in the field was lower in beetle-killed than in undisturbed stands. We demonstrate that stand mortality caused by prior beetle attacks of mature pines have cascading effects on seedling secondary chemistry, growth and survival, probably mediated through effects on below-ground mutualisms. PMID:26033270

  13. Modeling Landscape-Level Spatial Variation in Sex Ratio Skew in the Mountain Pine Beetle (Coleoptera: Curculionidae).

    PubMed

    James, Patrick M A; Janes, Jasmine K; Roe, Amanda D; Cooke, Barry J

    2016-08-01

    Through their influence on effective population sizes, sex ratio skew affects population dynamics. We examined spatial variation in female-biased sex ratios in the mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak in western Canada to better understand how environmental context affects sex ratio skew. Our specific objectives were to: 1) characterize spatial variation in mountain pine beetle sex ratio; 2) test previously asserted hypotheses that beetle sex ratio varies with tree diameter and year in outbreak; and 3) develop predictive models of sex ratio skew for larval and adult populations. Using logistic regression, we modeled the probability that an individual beetle (n = 2,369) was female as a function of multiple environmental variables across 34 stands in British Columbia and Alberta, Canada. We identified a consistent female-biased sex ratio with significantly greater skew in adults (2:1, n = 713) than in larvae (1.76:1, n = 1,643). We found that the proportion of larval females increased with decreasing tree size and with outbreak age. However, adults did not respond to tree size and larvae did not respond to outbreak age. Predictive models differed between larvae and adults. All identified models perform well and included predictors related to weather, tree diameter, and year in outbreak. Female-biased sex ratios appear to originate from differential male mortality during development rather than from sex-biased oviposition, suggesting sex ratio skew is not the cause of outbreaks, but rather a consequence. PMID:27209334

  14. Ectomycorrhizal fungi mediate indirect effects of a bark beetle outbreak on secondary chemistry and establishment of pine seedlings.

    PubMed

    Karst, Justine; Erbilgin, Nadir; Pec, Gregory J; Cigan, Paul W; Najar, Ahmed; Simard, Suzanne W; Cahill, James F

    2015-11-01

    Dendroctonus ponderosae has killed millions of Pinus contorta in western North America with subsequent effects on stand conditions, including changes in light intensity, needle deposition, and the composition of fungal community mutualists, namely ectomycorrhizal fungi. It is unknown whether these changes in stand conditions will have cascading consequences for the next generation of pine seedlings. To test for transgenerational cascades on pine seedlings, we tested the effects of fungal inoculum origin (beetle-killed or undisturbed stands), light intensity and litter (origin and presence) on seedling secondary chemistry and growth in a glasshouse. We also tracked survival of seedlings over two growing seasons in the same stands from which fungi and litter were collected. Fungal communities differed by inoculum origin. Seedlings grown with fungi collected from beetle-killed stands had lower monoterpene concentrations and fewer monoterpene compounds present compared with seedlings grown with fungi collected from undisturbed stands. Litter affected neither monoterpenes nor seedling growth. Seedling survival in the field was lower in beetle-killed than in undisturbed stands. We demonstrate that stand mortality caused by prior beetle attacks of mature pines have cascading effects on seedling secondary chemistry, growth and survival, probably mediated through effects on below-ground mutualisms.

  15. Modeling Landscape-Level Spatial Variation in Sex Ratio Skew in the Mountain Pine Beetle (Coleoptera: Curculionidae).

    PubMed

    James, Patrick M A; Janes, Jasmine K; Roe, Amanda D; Cooke, Barry J

    2016-08-01

    Through their influence on effective population sizes, sex ratio skew affects population dynamics. We examined spatial variation in female-biased sex ratios in the mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak in western Canada to better understand how environmental context affects sex ratio skew. Our specific objectives were to: 1) characterize spatial variation in mountain pine beetle sex ratio; 2) test previously asserted hypotheses that beetle sex ratio varies with tree diameter and year in outbreak; and 3) develop predictive models of sex ratio skew for larval and adult populations. Using logistic regression, we modeled the probability that an individual beetle (n = 2,369) was female as a function of multiple environmental variables across 34 stands in British Columbia and Alberta, Canada. We identified a consistent female-biased sex ratio with significantly greater skew in adults (2:1, n = 713) than in larvae (1.76:1, n = 1,643). We found that the proportion of larval females increased with decreasing tree size and with outbreak age. However, adults did not respond to tree size and larvae did not respond to outbreak age. Predictive models differed between larvae and adults. All identified models perform well and included predictors related to weather, tree diameter, and year in outbreak. Female-biased sex ratios appear to originate from differential male mortality during development rather than from sex-biased oviposition, suggesting sex ratio skew is not the cause of outbreaks, but rather a consequence.

  16. Streamwater Chemistry and Nutrient Export During Five Years of Bark Beetle Infestation of Subalpine Watersheds at the Fraser Experimental Forest

    NASA Astrophysics Data System (ADS)

    Rhoades, C.; Elder, K.; Hubbard, R.; Porth, L.

    2008-12-01

    Forested watersheds of western North America are currently undergoing rapid and extensive canopy mortality caused by a variety of insect species. The mountain pine bark beetle (Dendroctonus ponderosae) began to attack lodgepole pine (Pinus contorta) at the USFS Fraser Experimental Forest in central Colorado in 2002. By 2007, bark beetles had killed 78% of the overstory pine in Fraser research watersheds on average. The hydrologic, climatic, biogeochemical and vegetation records at the Fraser Experimental Forest provide a unique opportunity to quantify the impacts of this widespread, but poorly understood forest disturbance relative to a multi-decade pre-disturbance period. Here we compare seasonal streamwater chemistry and annual nutrient export for the five years since the bark beetle outbreak began with the pre- attack record. Patterns in post-outbreak streamwater biogeochemistry are compared to changes is species composition and proportional loss of overstory basal area for four basins. The influence of the outbreak will depend upon an aggregate of short (i.e. halted overstory water and nutrient use) and longer-term (i.e. altered canopy interception, windthrow, and understory growth) processes, so the hydrologic and biogeochemical implications of current beetle activity will not be fully realized for decades.

  17. Responses of Dendroctonus brevicomis (Coleoptera: Curculionidae) in behavioral assays: implications to development of a semiochemical-based tool for tree protection.

    PubMed

    Fettig, Christopher J; McKelvey, Stephen R; Dabney, Christopher P; Huber, Dezene P W

    2012-02-01

    Currently, techniques for managing western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Curculionidae, Scolytinae), infestations are limited to tree removals (thinning) that reduce stand density and presumably host susceptibility, and/or the use of insecticides to protect individual trees. There continues to be significant interest in developing an effective semiochemical-based tool for protecting trees from D. brevicomis attack, largely as an alternative to conventional insecticides. The responses of D. brevicomis to tree volatiles and verbenone were documented in eight experiments (trapping assays) conducted over a 4-yr period in which 88,942 individuals were collected. Geraniol, a tree volatile unique to Pinus ponderosa that elicits female-specific antennal responses in D. brevicomis, did not affect D. brevicomis behavior. Blends of two green leaf alcohols [hexanol + (Z)-3-hexen-1-ol] tested at two release rates (5.0 and 100.0 mg/d) had no effect on the response of D. brevicomis to attractant-baited traps. A nine-component blend [benzaldehyde, benzyl alcohol, guaiacol, nonanal, salicylaldehyde, (E)-2-hexenal, (E)-2-hexen-1-ol, (Z)-2-hexen-1-ol, and (-) -verbenone; NAVV] and subsequent revisions of this blend disrupted the response of D. brevicomis to attractant-baited traps in all experiments. The inhibitory effect of a revised five-component blend [nonanal, (E)-2-hexenal, (E)-2-hexen-1-ol, (Z)-2-hexen-1-ol, and (-)-verbenone; NAVV5] on the response of mountain pine beetle, D. ponderosae Hopkins, to attractant-baited traps was also documented. Acetophenone significantly reduced D. brevicomis attraction, but was not as effective as verbenone alone. Acetophenone increased the effectiveness of NAVV5 in one of two experiments. Furthermore, by adding acetophenone to NAVV5 we were able to remove the aldehydes from NAVV5 without compromising effectiveness, resulting in a novel four-component blend [acetophenone, (E)-2-hexen-1-ol + (Z)-2-hexen-1-ol, and

  18. Contrasting Patterns of Diterpene Acid Induction by Red Pine and White Spruce to Simulated Bark Beetle Attack, and Interspecific Differences in Sensitivity Among Fungal Associates.

    PubMed

    Mason, Charles J; Klepzig, Kier D; Kopper, Brian J; Kersten, Philip J; Illman, Barbara L; Raffa, Kenneth F

    2015-06-01

    Conifers possess a suite of physiochemical defenses that protect their subcortical tissues from bark beetle - fungal complexes. These defenses include rapid induction of terpenoids and phenolics at the site of attack. Studies of the distribution, induction, and bioactivity of conifer terpenoids have focused heavily on monoterpenes. We assessed induction of diterpene acids in white spruce (Picea glauca) and red pine (Pinus resinosa) to fungal associates of two bark beetles, and the responses of four spruce beetle (Dendroctonus rufipennis)-associated fungi to three diterpene acids. Constitutive phloem contents differed between species, in that red pine had extremely low concentrations of diterpene acids, whereas white spruce had substantial constitutive levels. Induction differed quantitatively. Both red pine and white spruce exhibited marked increases, but red pine underwent greater increases and achieved higher concentrations than white spruce. Induction also differed qualitatively in that red pine showed lower diversity and fewer compositional changes during induction than white spruce. In red pine,fungal inoculation accompanying wounding elicited greater increases than wounding alone, but in white spruce total concentrations were higher following wounding alone. Spruce beetle fungal symbiont growth varied among species and compounds. Some diterpenes elicited both stimulatory and inhibitory effects on fungi, depending on concentration. All four fungi exhibited higher tolerances compared to those associated with pine bark beetles in previous studies. Variation in tolerances to, and potentially metabolism of, diterpene acids by symbionts may reflect differences in constitutive levels between spruce and pine, and partially explain differences in concentrations achieved during induction.

  19. Determination of the compositional change (1999-2006) in the pine forests of British Columbia due to mountain pine beetle infestation.

    PubMed

    Robertson, Colin; Farmer, Carson J Q; Nelson, Trisalyn A; Mackenzie, Ian K; Wulder, Michael A; White, Joanne C

    2009-11-01

    The current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak in British Columbia and Alberta is the largest recorded forest pest infestation in Canadian history. We integrate a spatial hierarchy of mountain pine beetle and forest health monitoring data, collected between 1999 and 2006, with provincial forest inventory data, and generate three information products representing 2006 forest conditions in British Columbia: cumulative percentage of pine infested by mountain pine beetle, percentage of pine uninfested, and the change in the percentage of pine on the landscape. All input data were formatted to a standardized spatial representation (1 ha minimum mapping unit), with preference given to the most detailed monitoring data available at a given location for characterizing mountain pine beetle infestation conditions. The presence or absence of mountain pine beetle attack was validated using field data (n = 2054). The true positive rate for locations of red attack damage over all years was 92%. Classification of attack severity was validated using the Kruskal gamma statistic (gamma = 0.49). Error between the survey data and field data was explored using spatial autoregressive (SAR) models, which indicated that percentage pine and year of infestation were significant predictors of survey error at alpha = 0.05. Through the integration of forest inventory and infestation survey data, the total area of pine infested is estimated to be between 2.89 and 4.14 million hectares. The generated outputs add value to existing monitoring data and provide information to support management and modeling applications.

  20. Gene expression analysis of overwintering mountain pine beetle larvae suggests multiple systems involved in overwintering stress, cold hardiness, and preparation for spring development

    PubMed Central

    Bonnett, Tiffany; Pitt, Caitlin; Spooner, Luke J.; Fraser, Jordie; Yuen, Macaire M.S.; Keeling, Christopher I.; Bohlmann, Jörg; Huber, Dezene P.W.

    2016-01-01

    Cold-induced mortality has historically been a key aspect of mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), population control, but little is known about the molecular basis for cold tolerance in this insect. We used RNA-seq analysis to monitor gene expression patterns of mountain pine beetle larvae at four time points during their overwintering period—early-autumn, late-autumn, early-spring, and late-spring. Changing transcript profiles over the winter indicates a multipronged physiological response from larvae that is broadly characterized by gene transcripts involved in insect immune responses and detoxification during the autumn. In the spring, although transcripts associated with developmental process are present, there was no particular biological process dominating the transcriptome. PMID:27441109

  1. Gene expression analysis of overwintering mountain pine beetle larvae suggests multiple systems involved in overwintering stress, cold hardiness, and preparation for spring development.

    PubMed

    Robert, Jeanne A; Bonnett, Tiffany; Pitt, Caitlin; Spooner, Luke J; Fraser, Jordie; Yuen, Macaire M S; Keeling, Christopher I; Bohlmann, Jörg; Huber, Dezene P W

    2016-01-01

    Cold-induced mortality has historically been a key aspect of mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), population control, but little is known about the molecular basis for cold tolerance in this insect. We used RNA-seq analysis to monitor gene expression patterns of mountain pine beetle larvae at four time points during their overwintering period-early-autumn, late-autumn, early-spring, and late-spring. Changing transcript profiles over the winter indicates a multipronged physiological response from larvae that is broadly characterized by gene transcripts involved in insect immune responses and detoxification during the autumn. In the spring, although transcripts associated with developmental process are present, there was no particular biological process dominating the transcriptome.

  2. Gene expression analysis of overwintering mountain pine beetle larvae suggests multiple systems involved in overwintering stress, cold hardiness, and preparation for spring development.

    PubMed

    Robert, Jeanne A; Bonnett, Tiffany; Pitt, Caitlin; Spooner, Luke J; Fraser, Jordie; Yuen, Macaire M S; Keeling, Christopher I; Bohlmann, Jörg; Huber, Dezene P W

    2016-01-01

    Cold-induced mortality has historically been a key aspect of mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), population control, but little is known about the molecular basis for cold tolerance in this insect. We used RNA-seq analysis to monitor gene expression patterns of mountain pine beetle larvae at four time points during their overwintering period-early-autumn, late-autumn, early-spring, and late-spring. Changing transcript profiles over the winter indicates a multipronged physiological response from larvae that is broadly characterized by gene transcripts involved in insect immune responses and detoxification during the autumn. In the spring, although transcripts associated with developmental process are present, there was no particular biological process dominating the transcriptome. PMID:27441109

  3. Lady beetles of South Dakota

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lady beetles are one of the most familiar groups of beneficial insects. Farmers and gardeners appreciate them for devouring insect pests. Both adult lady beetles and caterpillar-like juveniles eat pests. Lady beetles are recognizable by their red and orange colors that contrast with black spots and...

  4. The push-pull tactic for mitigation of mountain pine beetle (Coleoptera: Curculionidae) damage in lodgepole and whitebark pines.

    PubMed

    Gillette, Nancy E; Mehmel, Constance J; Mori, Sylvia R; Webster, Jeffrey N; Wood, David L; Erbilgin, Nadir; Owen, Donald R

    2012-12-01

    In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (Dendroctonus ponderosae Hopkins) in two studies. The first was conducted on replicated 4.04-ha plots in lodgepole pine stands (California, 2008) and the second on 0.81-ha plots in whitebark pine stands (Washington, 2010). In both studies, D. ponderosae population levels were moderate to severe. The treatments were 1) push-only (D. ponderosae antiaggregant semiochemicals alone); 2) push-pull (D. ponderosae antiaggregants plus perimeter traps placed at regular intervals, baited with four-component D. ponderosae aggregation pheromone); and 3) untreated controls. We installed monitoring traps baited with two-component D. ponderosae lures inside each plot to assess effect of treatments on beetle flight. In California, fewer beetles were collected in push-pull treated plots than in control plots, but push-only did not have a significant effect on trap catch. Both treatments significantly reduced the rate of mass and strip attacks by D. ponderosae, but the difference in attack rates between push-pull and push-only was not significant. In Washington, both push-pull and push-only treatments significantly reduced numbers of beetles caught in traps. Differences between attack rates in treated and control plots in Washington were not significant, but the push-only treatment reduced attack rates by 30% compared with both the control and push-pull treatment. We conclude that, at these spatial scales and beetle densities, push-only may be preferable for mitigating D. ponderosae attack because it is much less expensive, simpler, and adding trap-out does not appear to improve efficacy. PMID:23321106

  5. The push-pull tactic for mitigation of mountain pine beetle (Coleoptera: Curculionidae) damage in lodgepole and whitebark pines.

    PubMed

    Gillette, Nancy E; Mehmel, Constance J; Mori, Sylvia R; Webster, Jeffrey N; Wood, David L; Erbilgin, Nadir; Owen, Donald R

    2012-12-01

    In an attempt to improve semiochemical-based treatments for protecting forest stands from bark beetle attack, we compared push-pull versus push-only tactics for protecting lodgepole pine (Pinus contorta Douglas ex Loudon) and whitebark pine (Pinus albicaulis Engelm.) stands from attack by mountain pine beetle (Dendroctonus ponderosae Hopkins) in two studies. The first was conducted on replicated 4.04-ha plots in lodgepole pine stands (California, 2008) and the second on 0.81-ha plots in whitebark pine stands (Washington, 2010). In both studies, D. ponderosae population levels were moderate to severe. The treatments were 1) push-only (D. ponderosae antiaggregant semiochemicals alone); 2) push-pull (D. ponderosae antiaggregants plus perimeter traps placed at regular intervals, baited with four-component D. ponderosae aggregation pheromone); and 3) untreated controls. We installed monitoring traps baited with two-component D. ponderosae lures inside each plot to assess effect of treatments on beetle flight. In California, fewer beetles were collected in push-pull treated plots than in control plots, but push-only did not have a significant effect on trap catch. Both treatments significantly reduced the rate of mass and strip attacks by D. ponderosae, but the difference in attack rates between push-pull and push-only was not significant. In Washington, both push-pull and push-only treatments significantly reduced numbers of beetles caught in traps. Differences between attack rates in treated and control plots in Washington were not significant, but the push-only treatment reduced attack rates by 30% compared with both the control and push-pull treatment. We conclude that, at these spatial scales and beetle densities, push-only may be preferable for mitigating D. ponderosae attack because it is much less expensive, simpler, and adding trap-out does not appear to improve efficacy.

  6. Combining land surface temperature and shortwave infrared reflectance for early detection of mountain pine beetle infestations in western Canada

    NASA Astrophysics Data System (ADS)

    Sprintsin, Michael; Chen, Jing M.; Czurylowicz, Peter

    2011-01-01

    The current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak, which began in 1999, continues to be the leading cause of pine tree mortality in British Columbia. Information regarding the location and spatial extent of the current attack is required for mitigating practices and forest inventory updates. This information is available from spaceborne observations. Unfortunately, the monitoring of the mountain pine beetle outbreak using remote sensing is usually limited to the visible stage at which the expansion of the attack beyond its initial hosts is unpreventable. The disruption of the sap flow caused by a blue-staining fungi carried by the beetles leads to: 1. a decrease in the amount of liquid water stored in the canopy, 2. an increase in canopy temperature, and 3. an increase in shortwave infrared reflectance shortly after the infestation. As such, the potential for early beetle detection utilizing thermal remote sensing is possible. Here we present a first attempt to detect a mountain pine beetle attack at its earliest stage (green attack stage when the foliage remains visibly green after the attack) using the temperature condition index (TCI) derived from Landsat ETM+ imagery over an affected area in British Columbia. The lack of detailed ground survey data of actual green attack areas limits the accuracy of this research. Regardless, our results show that TCI has the ability to differentiate between affected and unaffected areas in the green attack stage, and thus it provides information on the possible epicenters of the attack and on the spatial extent of the outbreak at later stages (red attack and gray attack). Furthermore, we also developed a moisture condition index (MCI) using both shortwave infrared and thermal infrared measurements. The MCI index is shown to be more effective than TCI in detecting the green attack stage and provides a more accurate picture of beetle spread patterns.

  7. Decline of ectomycorrhizal fungi following a mountain pine beetle epidemic.

    PubMed

    Treu, Roland; Karst, Justine; Randall, Morgan; Pec, Gregory J; Cigan, Paul W; Simard, Suzanne W; Cooke, Janice E K; Erbilgin, Nadir; Cahill, James F

    2014-04-01

    Forest die-off caused by mountain pine beetle (MPB; Dendroctonus ponderosa) is rapidly transforming western North American landscapes. The rapid and widespread death of lodgepole pine (Pinus contorta) will likely have cascading effects on biodiversity. One group particularly prone to such declines associated with MPB are ectomycorrhizal fungi, symbiotic organisms that can depend on pine for their survival, and are critical for stand regeneration. We evaluated the indirect effects of MPB on above- (community composition of epigeous sporocarps) and belowground (hyphal abundance) occurrences of ectomycorrhizal fungi across 11 forest stands. Along a gradient of mortality (0-82% pine killed), macromycete community composition changed; this shift was driven by a decrease in the species richness of ectomycorrhizal fungi. Both the proportion of species that were ectomycorrhizal and hyphal length in the soil declined with increased MPB-caused pine mortality; < 10% of sporocarp species were ectomycorrhizal in stands with high pine mortality compared with > 70% in stands without MPB attacks. The rapid range expansion of a native insect results not only in the widespread mortality of an ecologically and economically important pine species, but the effect of MPB may also be exacerbated by the concomitant decline of fungi crucial for recovery of these forests. PMID:24933827

  8. Slope Stability Analysis of Mountain Pine Beetle Impacted Areas

    NASA Astrophysics Data System (ADS)

    Bogenschuetz, N. M.; Bearup, L. A.; Maxwell, R. M.; Santi, P. M.

    2015-12-01

    The mountain pine beetle (MPB), Dendroctonus ponderosae, has caused significant tree mortality within North America. Specifically, the MPB affects ponderosa pine and lodgepole pine forests within the Rocky Mountains with approximately 3.4 million acres of forest impacted over the past 20 years. The full impacts of such unprecedented tree mortality on hydrology and slope stability is not well understood. This work studies the affects of MPB infestation on slope instability. A large-scale statistical analysis of MPB and slope stability is combined with a more in-depth analysis of the factors that contribute to slope stability. These factors include: slope aspect, slope angle, root decay, regrowth and hydrologic properties, such as water table depth and soil moisture. Preliminary results show that MPB may affect a greater number of north- and east-facing slopes. This is in accordance with more water availability and a higher MPB impacted tree density on north-facing slopes which, in turn, could potentially increase the probability of slope failure. Root strength is predicted to decrease as the roots stop transpiring 3-4 years proceeding infestation. However, this effect on the hillslope is likely being counterbalanced by the regrowth of grasses, forbs, shrubs, and trees. In addition, the increase in water table height from the lack of transpiring trees is adding a driving force to the slopes. The combination of all these factors will be used in order to assess the effects of MPB tree mortality on slope stability.

  9. Decline of ectomycorrhizal fungi following a mountain pine beetle epidemic.

    PubMed

    Treu, Roland; Karst, Justine; Randall, Morgan; Pec, Gregory J; Cigan, Paul W; Simard, Suzanne W; Cooke, Janice E K; Erbilgin, Nadir; Cahill, James F

    2014-04-01

    Forest die-off caused by mountain pine beetle (MPB; Dendroctonus ponderosa) is rapidly transforming western North American landscapes. The rapid and widespread death of lodgepole pine (Pinus contorta) will likely have cascading effects on biodiversity. One group particularly prone to such declines associated with MPB are ectomycorrhizal fungi, symbiotic organisms that can depend on pine for their survival, and are critical for stand regeneration. We evaluated the indirect effects of MPB on above- (community composition of epigeous sporocarps) and belowground (hyphal abundance) occurrences of ectomycorrhizal fungi across 11 forest stands. Along a gradient of mortality (0-82% pine killed), macromycete community composition changed; this shift was driven by a decrease in the species richness of ectomycorrhizal fungi. Both the proportion of species that were ectomycorrhizal and hyphal length in the soil declined with increased MPB-caused pine mortality; < 10% of sporocarp species were ectomycorrhizal in stands with high pine mortality compared with > 70% in stands without MPB attacks. The rapid range expansion of a native insect results not only in the widespread mortality of an ecologically and economically important pine species, but the effect of MPB may also be exacerbated by the concomitant decline of fungi crucial for recovery of these forests.

  10. Model Analysis of Spatial Patterns in Mountain Pine Beetle Outbreaks.

    PubMed

    Logan; White; Bentz; Powell

    1998-06-01

    The mountain pine beetle [MPB, Dendroctonus ponderosae Hopkins (Coleoptera: Scolytidae)] is an aggressive bark beetle, one that typically needs to kill host trees in order to successfully reproduce. This ecological adaptation has resulted in an organism that is both economically important and ecologically significant. Even though significant resources have been expended on MPB research, and a great deal of knowledge exists regarding individual aspects of MPB ecology, some of the most basic questions regarding outbreaks remain unanswered. In our opinion, one reason for the lack of synthesis and predictive power is the inadequate treatment of spatial dynamics in outbreak theories. This paper explicitly addresses the role of spatial dynamics in the precipitation and propagation of MPB outbreaks. We first describe a spatially dynamic model of the MPB/forest interaction that includes chemical ecology, spatial redistribution of beetles, attack, and resulting host mortality. The model is a system of 6 coupled, partial differential equations with 7 state variables and 20 parameters. It represents an attempt to capture the relatively complex predator/prey interaction between MPB and host trees by including the minimum phenomenological descriptions necessary for ecological credibility. This system of equations describes the temporal dynamics of: beetle attraction as a function of pheromone concentration; the change in numbers of flying and nesting beetles; tree resistance/susceptibility; and tree recovery from attack. Spatial dynamics are modeled by fluxes due to gradients in pheromones and kairomones, and the random redistribution of beetles in absence of semiochemicals. We then use the parameterized model to explore three issues central to the ecology of MPB/forest interaction. The first of these is in response to the need for objective ways to compare patterns of successful beetle attacks as they evolve in space. Simulation results indicate that at endemic levels, the

  11. Nesting ecology of boreal forest birds following a massive outbreak of spruce beetles

    USGS Publications Warehouse

    Matsuoka, S.M.; Handel, C.M.

    2007-01-01

    We studied breeding dark-eyed juncos (Junco hyemalis), yellow-rumped warblers (Dendroica coronata), and spruce-nesting birds from 1997 to 1998 among forests with different levels of spruce (Picea spp.) mortality following an outbreak of spruce beetles (Dendroctonus rufipennis) in Alaska, USA. We identified species using live and beetle-killed spruce for nest sites and monitored nests to determine how the outbreak influenced avian habitat selection and reproduction. We tested predictions that 1) nesting success of ground-nesting juncos would increase with spruce mortality due to proliferation of understory vegetation available to conceal nests from predators, 2) nesting success of canopy-nesting warblers would decrease with spruce mortality due to fewer live spruce in which to conceal nests, and 3) both species would alter nest-site selection in response to disturbance. Juncos did not benefit from changes in understory vegetation; nesting success in highly disturbed stands (46%) was comparable to that in undisturbed habitats throughout their range. In stands with low spruce mortality, nesting success of juncos was low (5%) and corresponded with high densities of red squirrels (Tamiasciurus hudsonicus). Yellow-rumped warblers nested exclusively in spruce, but success did not vary with spruce mortality. As disturbance increased, nesting warblers switched from selecting forest patches with high densities of live white spruce (Picea glauca) to patches with beetle-killed spruce. Warblers also placed nests in large-diameter live or beetle-killed spruce, depending on which was more abundant in the stand, with no differences in nesting success. Five of the 12 other species of spruce-nesting birds also used beetle-killed spruce as nest sites. Because beetle-killed spruce can remain standing for >50 years, even highly disturbed stands provide an important breeding resource for boreal forest birds. We recommend that boreal forest managers preserve uncut blocks of infested

  12. Waves and Water Beetles

    ERIC Educational Resources Information Center

    Tucker, Vance A.

    1971-01-01

    Capillary and gravity water waves are related to the position, wavelength, and velocity of an object in flowing water. Water patterns are presented for ships and the whirling beetle with an explanation of how the design affects the objects velocity and the observed water wavelengths. (DS)

  13. Pine Beetle Detection

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Earth Systems Science Office scientists worked with officials in St. Tammany Parish, La., to detect and battle pine beetle infestation in Fontainebleu State Park. The scientists used a new method of detecting plant stress by using special lenses and modified sensors to detect a change in light levels given off by the plant before the stress is visible to the naked eye.

  14. Beetles, Biofuel, and Coffee

    SciTech Connect

    Ceja-Navarro, Javier

    2015-05-06

    Berkeley Lab scientist Javier Ceja-Navarro discusses his research on the microbial populations found the guts of insects, specifically the coffee berry borer, which may lead to better pest management and the passalid beetle, which could lead to improved biofuel production.

  15. Bacteria influence mountain pine beetle brood development through interactions with symbiotic and antagonistic fungi: implications for climate-driven host range expansion.

    PubMed

    Therrien, Janet; Mason, Charles J; Cale, Jonathan A; Adams, Aaron; Aukema, Brian H; Currie, Cameron R; Raffa, Kenneth F; Erbilgin, Nadir

    2015-10-01

    Bark beetles are associated with diverse communities of symbionts. Although fungi have received significant attention, we know little about how bacteria, and in particular their interactions with fungi, affect bark beetle reproduction. We tested how interactions between four bacterial associates, two symbiotic fungi, and two opportunistic fungi affect performance of mountain pine beetles (Dendroctonus ponderosae) in host tissue. We compared beetle performance in phloem of its historical host, lodgepole pine (Pinus contorta), and its novel host recently accessed through warming climate, jack pine (Pinus banksiana). Overall, beetles produced more larvae, and established longer ovipositional and larval galleries in host tissue predominantly colonized by the symbiotic fungi, Grosmannia clavigera, or Ophiostoma montium than by the opportunistic colonizer Aspergillus and to a lesser extent, Trichoderma. This occurred in both historical and naïve hosts. Impacts of bacteria on beetle reproduction depended on particular fungus-bacterium combinations and host species. Some bacteria, e.g., Pseudomonas sp. D4-22 and Hy4T4 in P. contorta and Pseudomonas sp. Hy4T4 and Stenotrophomonas in P. banksiana, reduced antagonistic effects by Aspergillus and Trichoderma resulting in more larvae and longer ovipositional and larval galleries. These effects were not selective, as bacteria also reduced beneficial effects by symbionts in both host species. Interestingly, Bacillus enhanced antagonistic effects by Aspergillus in both hosts. These results demonstrate that bacteria influence brood development of bark beetles in host tissue. They also suggest that climate-driven range expansion of D. ponderosae through the boreal forest will not be significantly constrained by requirements of, or interactions among, its microbial associates. PMID:26037523

  16. Bacteria influence mountain pine beetle brood development through interactions with symbiotic and antagonistic fungi: implications for climate-driven host range expansion.

    PubMed

    Therrien, Janet; Mason, Charles J; Cale, Jonathan A; Adams, Aaron; Aukema, Brian H; Currie, Cameron R; Raffa, Kenneth F; Erbilgin, Nadir

    2015-10-01

    Bark beetles are associated with diverse communities of symbionts. Although fungi have received significant attention, we know little about how bacteria, and in particular their interactions with fungi, affect bark beetle reproduction. We tested how interactions between four bacterial associates, two symbiotic fungi, and two opportunistic fungi affect performance of mountain pine beetles (Dendroctonus ponderosae) in host tissue. We compared beetle performance in phloem of its historical host, lodgepole pine (Pinus contorta), and its novel host recently accessed through warming climate, jack pine (Pinus banksiana). Overall, beetles produced more larvae, and established longer ovipositional and larval galleries in host tissue predominantly colonized by the symbiotic fungi, Grosmannia clavigera, or Ophiostoma montium than by the opportunistic colonizer Aspergillus and to a lesser extent, Trichoderma. This occurred in both historical and naïve hosts. Impacts of bacteria on beetle reproduction depended on particular fungus-bacterium combinations and host species. Some bacteria, e.g., Pseudomonas sp. D4-22 and Hy4T4 in P. contorta and Pseudomonas sp. Hy4T4 and Stenotrophomonas in P. banksiana, reduced antagonistic effects by Aspergillus and Trichoderma resulting in more larvae and longer ovipositional and larval galleries. These effects were not selective, as bacteria also reduced beneficial effects by symbionts in both host species. Interestingly, Bacillus enhanced antagonistic effects by Aspergillus in both hosts. These results demonstrate that bacteria influence brood development of bark beetles in host tissue. They also suggest that climate-driven range expansion of D. ponderosae through the boreal forest will not be significantly constrained by requirements of, or interactions among, its microbial associates.

  17. Nitrogen concentration in mountain pine beetle larvae reflects nitrogen status of the tree host and two fungal associates.

    PubMed

    Cook, Stephen P; Shirley, Brian M; Zambino, Paul J

    2010-06-01

    Individual lodgepole pines (Pinus contorta) were fertilized with urea at nitrogen (N) inputs equivalent to 0, 315, or 630 kg/ha. Four months after application of the fertilizer, inner bark tissue N concentrations were significantly higher in the trees that had received the low dose (315 kg/ha) fertilization treatment than in the control trees; trees that had received the high-dose treatment (630 kg/ha) were intermediate and not significantly different from either of the other treatments. There was a significant positive correlation between N concentration in inner bark tissue and larval mountain pine beetle, Dendroctonus ponderosae (Coleoptera: Curculionidae, Scolytinae). In vitro studies on synthetic growth media examined effects of temperature and N concentration on N concentration of two common fungal associates of the mountain pine beetle (Ophiostoma clavigerum and Ophiostoma montium). Increasing N concentration in growth media significantly increased fungal N concentrations in both O. clavigerum and O. montium. Furthermore, N concentration was consistently higher in O. clavigerum than in O. montium. Neither species had sufficient growth at 30 degrees C, nor did O. clavigerum at 15 degrees C, to test N concentration. However, for O. montium, increasing temperatures decreased fungal N concentrations. There was no correlation between N concentration of O. clavigerum and growth temperature. Potential impacts of ingestion of the fungal species by developing mountain pine beetle larvae-infesting trees under various environmental conditions such as increasing temperatures are discussed.

  18. Relating severity of a mountain pine beetle outbreak to forest management history

    NASA Astrophysics Data System (ADS)

    Vorster, Anthony

    The availability of remote sensing imagery before, during, and after the recent mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic in the southern Rocky Mountains presents exciting opportunities for assessing the current state of forests and how forest management in previous decades influenced outbreak severity across the landscape. I mapped outbreak severity at a 30-m resolution using integrative spatial modeling. I predicted that: 1) outbreak severity can be accurately predicted and mapped at Fraser Experimental Forest, Colorado using stand characteristics with a boosted regression tree model, Landsat imagery, geographic information system (GIS) data, and field data; and 2) forest stands that were unmanaged since the 1950s will have higher outbreak severity compared to stands that were treated since the 1950s. Outbreak severity, measured by the ratio of dead lodgepole pine (Pinus contorta) basal area to the basal area of all trees, was mapped across Fraser Experimental Forest with a cross-validation correlation of 0.86 and a Spearman correlation with independently observed values of 0.64. The outbreak severity at stands harvested between 1954 and 1985 was lower than comparable uncut stands. Lessons learned about past treatments will inform forest management for future mountain pine beetle outbreaks.

  19. Synergism of turpentine and ethanol as attractants for certain pine-infesting beetles (Coleoptera)

    SciTech Connect

    Phillips, T.W.; Wilkening, A.J.; Atkinson, T.H.; Nation, J.L.; Wilkinson, R.C.; Foltz, J.L.

    1988-06-01

    Responses of seven species of pine-infesting beetles to traps baited with either turpentine, ethanol, turpentine and ethanol released from separate dispensers, or a 1:1 solution of turpentine and ethanol released from one dispenser were assessed in three field experiments. The weevil species, Pachylobius picivorus (Germar), and the cerambycid pine sawyer, Monochamus carolinenis (Olivier), were attracted to turpentine and were unaffected by the addition of ethanol. The ambrosia beetle, Xyleborus affinis Eichhoff, responded to ethanol alone but was not attracted to turpentine, nor did the presence of turpentine significantly affects its response to ethanol. The remaining four species) hylobius pales, M. titillator, Dendroctonus terebrans and x. pubescens) displayed responses to turpentine that were enhanced by the addition of ethanol, but in different ways according to the method of deployment. Reasons for increased responses by some species to a solution of turpentine and ethanol over the two released separately are not clear; they may lie in different dosages of evaporation rates of volatiles in the field. Laboratory analyses of trapped headspace volatiles from dispensers containing only turpentine and those containing a solution of turpentine and ethanol revealed no differences in the amounts of four principal monoterpene hydrocarbons (..cap alpha..-pinene, camphene, ..beta..-pinene, and limonene) released over time.

  20. Rapid identification and detection of pine pathogenic fungi associated with mountain pine beetles by padlock probes.

    PubMed

    Tsui, Clement K M; Wang, Bin; Khadempour, Lily; Alamouti, Sepideh Massoumi; Bohlmann, Jörg; Murray, Brent W; Hamelin, Richard C

    2010-10-01

    Fifteen million hectares of pine forests in western Canada have been attacked by the mountain pine beetle (Dendroctonus ponderosae; MPB), leading to devastating economic losses. Grosmannia clavigera and Leptographium longiclavatum, are two fungi intimately associated with the beetles, and are crucial components of the epidemic. To detect and discriminate these two closely related pathogens, we utilized a method based on ligase-mediated nucleotide discrimination with padlock probe technology, and signal amplification by hyperbranched rolling circle amplification (HRCA). Two padlock probes were designed to target species-specific single nucleotide polymorphisms (SNPs) located at the inter-generic spacer 2 region and large subunit of the rRNA respectively, which allows discrimination between the two species. Thirty-four strains of G. clavigera and twenty-five strains of L. longiclavatum representing a broad geographic origin were tested with this assay. The HRCA results were largely in agreement with the conventional identification based on morphology or DNA-based methods. Both probes can also efficiently distinguish the two MPB-associated fungi from other fungi in the MPB, as well as other related fungi in the order Ophiostomatales. We also tested this diagnostic method for the direct detection of these fungi from the DNA of MPB. A nested PCR approach was used to enrich amplicons for signal detection. The results confirmed the presence of these two fungi in MPB. Thus, the padlock probe assay coupled with HRCA is a rapid, sensitive and reproducible method for the identification and detection of these ophiostomatoid fungi.

  1. Soil Respiration Declines Following Beetle - Induced Forest Mortality in a Lodgepole Pine Forest

    NASA Astrophysics Data System (ADS)

    Borkhuu, B.; Peckham, S. D.; Norton, U.; Ewers, B. E.; Pendall, E.

    2014-12-01

    Lodgepole pine (Pinus contorta var. latifolia) forests in northern Colorado and southeast Wyoming have been undergoing a major mortality event owing to mountain pine beetle (Dendroctonus ponderosae) infestation since 2007. We studied biotic and abiotic drivers of growing season soil respiration in four mature stands experiencing different levels of mortality between 2008 and 2012 in the Medicine Bow Mountains, southeastern Wyoming, USA. For five years, beetle infestation significantly altered forest structure. Stand mortality was 30% and more than 80% in stands with the lowest and highest mortality, respectively. Understory vegetation cover increased by 50% for five years following beetle infestation. Needlefall was increased by more than 50% during first two years of beetle infestation compared to the pre-disturbance period. We did not observe an immediate increase in soil respiration following beetle infestation as suggested by some researchers. Soil respiration rates in midsummer ranged from 1.4 ± 0.1 μmol m-2 s-1 in stands with highest mortality to 3.1 ± 0.2 μmol m-2s-1 in uninfested stand. Live tree basal area was the dominant factor controlling soil respiration, explaining more than 60% of the interannual and spatial variations in response to the disturbance. In addition, soil respiration was significantly correlated with fine root biomass, which explained 55% of variations, providing strong evidence that autotrophic respiration dominated the forest soil respiration flux. Furthermore, the seasonality of soil respiration was controlled mainly by mean monthly precipitation and mid-day photosynthetically active radiation. Each factor predicted from 30% to 50% of seasonal soil respiration variability with the highest correlation coefficients in stand with the lowest mortality. Our results clearly indicate that the reduction of photosynthesis in trees over the infestation period significantly reduced soil respiration. The remaining activity in dead stands may

  2. Ecological consequences of mountain pine beetle outbreaks for wildlife in western North American forests

    USGS Publications Warehouse

    Saab, Victoria A.; Latif, Quresh S.; Rowland, Mary M.; Johnson, Tracey N.; Chalfoun, Anna D.; Buskirk, Steven W.; Heyward, Joslin E.; Dresser, Matthew A.

    2014-01-01

    Mountain pine beetle (Dendroctonus ponderosae) (MPB) outbreaks are increasingly prevalent in western North America, causing considerable ecological change in pine (Pinus spp.) forests with important implications for wildlife. We reviewed studies examining wildlife responses to MPB outbreaks and postoutbreak salvage logging to inform forest management and guide future research. Our review included 16 studies describing MPB outbreak relationships with 89 bird species and 6 studies describing relationships with 11 mammalian species, but no studies of reptiles or amphibians. We included studies that compared wildlife response metrics temporally (before versus after the outbreak) and spatially (across sites that varied in severity of outbreak) in relation to beetle outbreaks. Outbreaks ranged in size from 20,600 to ≥107 ha and studies occurred 1‐30 years after the peak MPB outbreak, but most studies were conducted over the short-term (i.e., ≤6 years after the peak of MPB-induced tree mortality). Birds were the only taxa studied frequently; however, high variability existed among those studies to allow many inferences, although some patterns were evident. Avian studies concluded that cavity-nesting species responded more favorably to beetle-killed forests than species with open-cup nests, and species nesting in the shrub layer favored outbreak forests compared with ground and open-cup canopy nesters that generally showed mixed relationships. Bark-drilling species as a group clearly demonstrated a positive short-term association with MPB epidemics compared with that of other foraging assemblages. Cavity-nesting birds that do not consume bark beetles (i.e., secondary cavity-nesting species and nonbark-drilling woodpeckers) also exhibited some positive responses to MPB outbreaks, although not as pronounced or consistent as those of bark-drilling woodpeckers. Mammalian responses to MPB outbreaks were mixed. Studies consistently reported negative effects of MPB

  3. Mountain Pine beetle disturbance and climate effects on subalpine forest carbon cycling

    NASA Astrophysics Data System (ADS)

    Trahan, N. A.; Moore, D. J.; Bowling, D. R.; Monson, R. K.

    2010-12-01

    Forest ecosystems in Western North America have experienced an epidemic outbreak of Mountain Pine beetle (Dendroctonus ponderosae), reducing net primary productivity and significantly compromising the potential for these ecosystems to sequester atmospheric carbon. Estimates of lost carbon sequestration and trajectories of future carbon uptake as these forests recover, are uncertain due to lack of fundamental knowledge about the carbon cycle processes that are impacted. Furthermore, the effects of this disturbance are informed by their interplay with important climatic drivers of subalpine carbon uptake such as the availability of snowmelt water. To examine some of these carbon cycle processes, we measured soil respiration rates, the 13C/12C of soil respired CO2, extractable soil carbon, and microbial biomass carbon in a chronosequence of plots consisting of lodgepole pines (Pinus contorta) that experienced beetle kill or were girdled (simulating beetle kill). The plots are located in the Niwot Ridge AmeriFlux and Fraser Experimental Forests of Colorado. The chronosequence extended from approximately 2002 to 2010. In addition, in 2008 and 2009 we amended and removed spring snow on a subset of girdled and control plots to isolate potential snowpack effects on the autotrophic and heterotrophic components of soil respiration. Soil respiration, extractable carbon, and microbial biomass carbon were higher in control plot soils compared to soils in plots with girdled or beetle killed trees. These differences were greatest between control soils and soils of more recently girdled and beetle killed trees. Over the growing season, we found the 13C/12C ratio of soil respired CO2 was enriched in plots with girdled trees compared to the control plots past the second year of treatment. Finally, ungirdled plots in 2009 responded to spring snow amendments with increased soil respiration rates and a more depleted signature of δ13C. These effects occurred in early summer during the

  4. Low-severity fire increases tree defense against bark beetle attacks.

    PubMed

    Hood, Sharon; Sala, Anna; Heyerdahl, Emily K; Boutin, Marion

    2015-07-01

    Induced defense is a common plant strategy in response to herbivory. Although abiotic damage, such as physical wounding, pruning, and heating, can induce plant defense, the effect of such damage by large-scale abiotic disturbances on induced defenses has not been explored and could have important consequences for plant survival facing future biotic disturbances. Historically, low-severity wildfire was a widespread, frequent abiotic disturbance in many temperate coniferous forests. Native Dendroctonus and Ips bark beetles are also a common biotic disturbance agent in these forest types and can influence tree mortality patterns after wildfire. Therefore, species living in these disturbance-prone environments with strategies to survive both frequent fire and bark beetle attack should be favored. One such example is Pinus ponderosa forests of western North America. These forests are susceptible to bark beetle attack and frequent, low-severity fire was common prior to European settlement. However, since the late 1800s, frequent, low-severity fires have greatly decreased in these forests. We hypothesized that non-lethal, low-severity, wildfire induces resin duct defense in P. ponderosa and that lack of low-severity fire relaxes resin duct defense in forests dependent on frequent, low-severity fire. We first compared axial resin duct traits between trees that either survived or died from bark beetle attacks. Next, we studied axial ducts using tree cores with crossdated chronologies in several natural P. ponderosa stands before and after an individual wildfire and, also, before and after an abrupt change in fire frequency in the 20th century. We show that trees killed by bark beetles invested less in resin ducts relative to trees that survived attack, suggesting that resin duct-related traits provide resistance against bark beetles. We then show low-severity fire induces resin duct production, and finally, that resin duct production declines when fire ceases. Our results

  5. Efficacy of verbenone and green leaf volatiles for protecting whitebark and limber pines from attack by mountain pine beetle (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Gillette, Nancy E; Kegley, Sandra J; Costello, Sheryl L; Mori, Sylvia R; Webster, Jeffrey N; Mehmel, Constance J; Wood, David L

    2014-08-01

    To develop safe and effective methods to protect whitebark pines, Pinus albicaulis Engelmann, and limber pines, Pinus flexilis James, from attack by mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), we compared verbenone and verbenone plus green leaf volatiles (GLVs) for prevention of beetle attack. We used two strategies: area-wide protection where semiochemical-releasing flakes are dispersed over the forest floor, and individual tree tests where flakes are applied to tree trunks. The area-wide bioassays were conducted by applying verbenone- and GLV-releasing flakes without stickers to the forest floor on 0.81-ha plots dominated by whitebark pines in the State of Washington with four replicates. We conducted individual tree bioassays by applying the same formulations with stickers to whitebark and limber pines in Montana and Colorado, respectively. In all three situations, both verbenone-alone and verbenone plus GLVs significantly increased the proportion of trees escaping mass attack by beetles, but the two formulations were not significantly different from one another. Despite a lack of significance at a Bonferroni-adjusted α = 0.05, adding GLVs gave slightly greater absolute levels of tree protection in most cases. Monitoring traps placed in the area-wide treatments in Washington showed similar outcomes for numbers of beetles trapped: both treatments had significantly fewer beetles than controls, and they were not significantly different from one another. At peak flight, however, plots with GLVs combined with verbenone had roughly 40% fewer beetles than plots with verbenone alone. GLVs are considerably cheaper than verbenone, so tests of higher application rates may be warranted to achieve enhanced tree protection at reasonable cost.

  6. Wave-making by whirligig beetles (gyrinidae).

    PubMed

    Tucker, V A

    1969-11-14

    Swimming whirligig beetles (Dineutes carolinus) either make no waves at all or make conspicuous circular or vee-shaped patterns of capillary waves. The beetle's swimming speed can be determined from these wave patterns (or lack of them). Capillary waves precede the beetle for several body lengths, and their reflections may help the beetle avoid solid objects by echolocation. The gravity waves produced by a beetle are always longer than the beetle's hull length. Hence the waves do not interact with the hull to impose an upper limit on speed as they do with conventional ships. Although the beetles swim at high speeds, they apparently do not hydroplane. PMID:17815756

  7. Impact of mountain pine beetle induced mortality on forest carbon and water fluxes

    NASA Astrophysics Data System (ADS)

    Reed, David E.; Ewers, Brent E.; Pendall, Elise

    2014-10-01

    Quantifying impacts of ecological disturbance on ecosystem carbon and water fluxes will improve predictive understanding of biosphere—atmosphere feedbacks. Tree mortality caused by mountain pine bark beetles (Dendroctonus ponderosae) is hypothesized to decrease photosynthesis and water flux to the atmosphere while increasing respiration at a rate proportional to mortality. This work uses data from an eddy-covariance flux tower in a bark beetle infested lodgepole pine (Pinus contorta) forest to test ecosystem responses during the outbreak. Analyses were conducted on components of carbon (C) and water fluxes in response to disturbance and environmental factors (solar radiation, soil water content and vapor pressure deficit). Maximum CO2 uptake did not change as tree basal area mortality increased from 30 to 78% over three years of beetle disturbance. Growing season evapotranspiration varied among years while ecosystem water use efficiency (the ratio of net CO2 uptake to water vapor loss) did not change. Between 2009 and 2011, canopy water conductance increased from 98.6 to 151.7 mmol H2O m-2 s-1. Ecosystem light use efficiency of photosynthesis increased, with quantum yield increasing by 16% during the outbreak as light increased below the mature tree canopy and illuminated remaining vegetation more. Overall net ecosystem productivity was correlated with water flux and hence water availability. Average weekly ecosystem respiration, derived from light response curves and standard Ameriflux protocols for CO2 flux partitioning into respiration and gross ecosystem productivity, did not change as mortality increased. Separate effects of increased respiration and photosynthesis efficiency largely canceled one another out, presumably due to increased diffuse light in the canopy and soil organic matter decomposition resulting in no change in net CO2 exchange. These results agree with an emerging consensus in the literature demonstrating CO2 and H2O dynamics following large

  8. Effects of Temperature on Growth, Sporulation, and Competition of Mountain Pine Beetle Fungal Symbionts.

    PubMed

    Moore, Melissa L; Six, Diana L

    2015-08-01

    The mountain pine beetle, Dendroctonus ponderosae, depends on two fungi, Grosmannia clavigera and Ophiostoma montium, to augment a nutrient-poor woody food resource. Because the two fungi exert differential effects on the host beetle, temperature-driven differences in fungal growth and competition outcomes have a strong potential to influence host population dynamics. Weisolated fungi from beetles and wood from three locations in Montana and Utah, USA, and measured their growth rates and sporulation between 5 and 35 °C on artificial media. We also measured growth rates and percent resource capture for each fungus at 10, 15, 21, and 25 °C during inter- and intra-specific competition. G. clavigera excelled at resource capture at most temperatures. Its optimal growth temperature occurs around 20 °C while that of O. montium occurs near 30 °C. There was no effect of collection site on growth or sporulation; however, O. montium exhibited greater variability in response to temperature than did G. clavigera. Sporulation of G. clavigera was greatest at 30 °C while O. montium sporulated at low levels across all temperatures. During competition experiments, G. clavigera captured more resources than O. montium at most temperatures and captured a greater percentage of resources at a greater rate during inter-specific competition than during intra-specific competition. In contrast, O. montium captured a greater percentage of resources during intra-specific competition. These results demonstrate that temperature can differentially affect growth, sporulation, and resource capture of the two symbionts, indicating that it may be an important factor influencing the composition and dynamics of the symbiosis.

  9. Estimating the Effects of Mountain Pine Beetle Outbreaks on Biophysical and Biogeochemical Variables Using MODIS Products

    NASA Astrophysics Data System (ADS)

    Meddens, A. J.; Hicke, J. A.

    2009-12-01

    Insects such as mountain pine beetle (Dendroctonus ponderosae Hopkins) are major disturbances in forested ecosystems, affecting forest structure and function. In recent decades, mountain pine beetles have affected large forested areas in the United States and Canada. Insect disturbances impact biophysical variables important for atmosphere/ecosystem exchanges of mass, energy, and momentum as well as biogeochemical processes, notably carbon cycling. Our goal was to estimate the effects of insect disturbance, in particular mountain pine beetle infestations, on carbon cycling in Colorado by using MODIS biophysical and biogeochemical data products in conjunction with fine-resolution aerial imagery that identified the infestation locations. We classified a fine-resolution aerial image, acquired on August 13 2008 in Colorado, into five classes: (1) undisturbed forests, (2) red-attack (when needles are red and still on trees), (3) gray-attack (when trees have lost most of their needles), (4) herbaceous vegetation, and (5) non-vegetation. The classified aerial image was evaluated using field observations, and high accuracies were achieved. The classified aerial image was then aggregated to the MODIS resolution to investigate different levels of insect-caused tree mortality (i.e., the percentage of fine-resolution red-attack and gray-attack pixels in the aggregated pixels). MODIS-derived biophysical and biogeochemical products, including gross and net primary production, leaf area index (LAI), and surface albedo were overlaid on locations with the different levels of outbreak severity. Trajectories of these variables across time were extracted and pre- and post-outbreak values were compared. The outcomes of the effects of MPB on biophysical parameters can be used to increase understanding of impacts of insects to forest functioning and carbon cycling in the western United States.

  10. Snow Hydrology: Effects of Mountain Pine Beetle on Snowpack Characteristics

    NASA Astrophysics Data System (ADS)

    Welch, C. M.; Stoy, P. C.; Rains, F. A.; McGlynn, B. L.; Nippgen, F.; Kaiser, K.

    2011-12-01

    The future of water resources in the West is tenuous, as climatic changes have resulted in earlier spring freshets that have exacerbated summer droughts. Associated with climate changes to the physical environment are alterations to the biological environment that may impact snow dynamics; namely via the massive outbreaks of Mountain Pine Beetle, (MPB; Dendroctonus ponderosae) and other herbivores which have devastated millions of hectares in the Western U.S. and Canada. If snow accumulation and melt are determined by the physical environment of the snowpack, and forest canopies play a significant role in defining this physical environment, what changes to water resources in areas experiencing MPB outbreaks are likely to occur? Degradation of an infected forest's canopy is expected to produce an increase in shortwave flux density at the snow surface. Combined with a corresponding decrease of snow reflectance (albedo) from litterfall, we hypothesize that snowpacks in MPB-infested canopies will melt more rapidly, but also accumulate more snow due to decreased canopy interception, resulting in a larger spring freshet. Measurements of snow water equivalent, depth, and energy fluxes in two forested snowpacks and one clearcut snowpack were taken in the Tenderfoot Creek Forest located in the Little Belt Mountains of West-central Montana. One of the forested ecosystems is undergoing the initial phases of MPB attack, with a green canopy but observed pitch tubes. The other is experiencing a more advanced stage of MPB attack, with red needles dominating the canopy. The snowpack in the clearcut ecosystem melted out 11 days faster than in the forested ecosystems, and albedo in the red and green stands differed by only 5% on average. Continued monitoring and landscape-level extrapolation will improve understanding of biological, physical, and management disturbances on snowmelt at the watershed scale.

  11. Bark beetle effects on fuel profiles across a range of stand structures in Douglas-fir forests of Greater Yellowstone.

    PubMed

    Donato, Daniel C; Harvey, Brian J; Romme, William H; Simard, Martin; Turner, Monica G

    2013-01-01

    Consequences of bark beetle outbreaks for forest wildfire potential are receiving heightened attention, but little research has considered ecosystems with mixed-severity fire regimes. Such forests are widespread, variable in stand structure, and often fuel limited, suggesting that beetle outbreaks could substantially alter fire potentials. We studied canopy and surface fuels in interior Douglas-fir (Pseudotsuga menziesii v. glauca) forests in Greater Yellowstone, Wyoming, USA, to determine how fuel characteristics varied with time since outbreak of the Douglas-fir beetle (Dendroctonus pseudotsugae). We sampled five stands in each of four outbreak stages, validated for pre-outbreak similarity: green (undisturbed), red (1-3 yr), gray (4-14 yr), and silver (25-30 yr). General linear models were used to compare variation in fuel profiles associated with outbreak to variation associated with the range of stand structures (dense mesic forest to open xeric parkland) characteristic of interior Douglas-fir forest. Beetle outbreak killed 38-83% of basal area within stands, generating a mix of live trees and snags over several years. Canopy fuel load and bulk density began declining in the red stage via needle drop and decreased by approximately 50% by the silver stage. The dead portion of available canopy fuels peaked in the red stage at 41%. After accounting for background variation, there was little effect of beetle outbreak on surface fuels, with differences mainly in herbaceous biomass (50% greater in red stands) and coarse woody fuels (doubled in silver stands). Within-stand spatial heterogeneity of fuels increased with time since outbreak, and surface-to-crown continuity decreased and remained low because of slow/sparse regeneration. Collectively, results suggest reduced fire potentials in post-outbreak stands, particularly for crown fire after the red stage, although abundant coarse fuels in silver stands may increase burn residence time and heat release. Outbreak

  12. Intra-Annual Variation in Responses by Flying Southern Pine Beetles (Coleoptera: Curculionidae: Scolytinae) to Pheromone Component endo-Brevicomin.

    PubMed

    Sullivan, Brian T; Brownie, Cavell; Barrett, JoAnne P

    2016-08-01

    The southern pine beetle Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is attracted to an aggregation pheromone that includes the multifunctional pheromone component endo-brevicomin. The effect of endo-brevicomin on attractive lures varies from strong enhancement to reduction of beetle attraction depending upon release rate, lure component spacing, and proximity of beetle infestations. Anecdotal observations have further suggested that the effects of endo-brevicomin vary during the year. We investigated this possibility under nonoutbreak conditions in southwestern Mississippi where for two-and-a-half years we monitored traps baited with frontalin and the host odor alpha-pinene either (a) alone, or with an endo-brevicomin release device either (b) located directly on the trap, or (c) displaced 6 m away. The endo-brevicomin devices in our tests increased D. frontalis catches during all times of year, and 6 m displacement of the endo-brevicomin release device from the trap did not significantly alter responses except during the spring flight peak when displacement increased catches. Our data suggest that flying D. frontalis have a stronger tendency to avoid the immediate proximity of a release point of endo-brevicomin during their springtime dispersal flight when catches are greatest. Catches of Thanasimus dubius (F.) (Coleoptera: Cleridae), a major predator of D. frontalis, were not altered by endo-brevicomin, and ratios of D. frontalis to T. dubius changed over the course of the year. We discuss the possible effects of intra-annual variation in D. frontalis response to endo-brevicomin both on beetle attack behavior and use of endo-brevicomin as a lure adjuvant in D. frontalis population monitoring. PMID:27207264

  13. Intra-Annual Variation in Responses by Flying Southern Pine Beetles (Coleoptera: Curculionidae: Scolytinae) to Pheromone Component endo-Brevicomin.

    PubMed

    Sullivan, Brian T; Brownie, Cavell; Barrett, JoAnne P

    2016-08-01

    The southern pine beetle Dendroctonus frontalis Zimmermann (Coleoptera: Curculionidae: Scolytinae) is attracted to an aggregation pheromone that includes the multifunctional pheromone component endo-brevicomin. The effect of endo-brevicomin on attractive lures varies from strong enhancement to reduction of beetle attraction depending upon release rate, lure component spacing, and proximity of beetle infestations. Anecdotal observations have further suggested that the effects of endo-brevicomin vary during the year. We investigated this possibility under nonoutbreak conditions in southwestern Mississippi where for two-and-a-half years we monitored traps baited with frontalin and the host odor alpha-pinene either (a) alone, or with an endo-brevicomin release device either (b) located directly on the trap, or (c) displaced 6 m away. The endo-brevicomin devices in our tests increased D. frontalis catches during all times of year, and 6 m displacement of the endo-brevicomin release device from the trap did not significantly alter responses except during the spring flight peak when displacement increased catches. Our data suggest that flying D. frontalis have a stronger tendency to avoid the immediate proximity of a release point of endo-brevicomin during their springtime dispersal flight when catches are greatest. Catches of Thanasimus dubius (F.) (Coleoptera: Cleridae), a major predator of D. frontalis, were not altered by endo-brevicomin, and ratios of D. frontalis to T. dubius changed over the course of the year. We discuss the possible effects of intra-annual variation in D. frontalis response to endo-brevicomin both on beetle attack behavior and use of endo-brevicomin as a lure adjuvant in D. frontalis population monitoring.

  14. Evaluating Predators and Competitors in Wisconsin Red Pine Forests for Attraction to Mountain Pine Beetle Pheromones for Anticipatory Biological Control.

    PubMed

    Pfammatter, Jesse A; Krause, Adam; Raffa, Kenneth F

    2015-08-01

    Mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), is an irruptive tree-killing species native to pine forests of western North America. Two potential pathways of spread to eastern forests have recently been identified. First, warming temperatures have driven range expansion from British Columbia into Albertan jack pine forests that are contiguous with the Great Lakes region. Second, high temperatures and drought have fostered largescale outbreaks within the historical range, creating economic incentives to salvage killed timber by transporting logs to midwestern markets, which risks accidental introduction. We evaluated the extent to which local predators and competitors that exploit bark beetle semiochemicals would respond to D. ponderosae in Wisconsin. We emulated D. ponderosae attack by deploying lures containing synthetic aggregation pheromones with and without host tree compounds and blank control traps in six red pine plantations over 2 yr. Predator populations were high in these stands, as evidenced by catches in positive control traps, baited with pheromones of local bark beetles and were deployed distant from behavioral choice plots. Only one predator, Thanasimus dubius F. (Coleoptera: Cleridae) was attracted to D. ponderosae's aggregation pheromones relative to blank controls, and its attraction was relatively weak. The most common bark beetles attracted to these pheromones were lower stem and root colonizers, which likely would facilitate rather than compete with D. ponderosae. There was some, but weak, attraction of potentially competing Ips species. Other factors that might influence natural enemy impacts on D. ponderosae in midwestern forests, such as phenological synchrony and exploitation of male-produced pheromones, are discussed.

  15. Changes to the N cycle following bark beetle outbreaks in two contrasting conifer forest types.

    PubMed

    Griffin, Jacob M; Turner, Monica G

    2012-10-01

    Outbreaks of Dendroctonus beetles are causing extensive mortality in conifer forests throughout North America. However, nitrogen (N) cycling impacts among forest types are not well known. We quantified beetle-induced changes in forest structure, soil temperature, and N cycling in Douglas-fir (Pseudotsuga menziesii) forests of Greater Yellowstone (WY, USA), and compared them to published lodgepole pine (Pinus contorta var. latifolia) data. Five undisturbed stands were compared to five beetle-killed stands (4-5 years post-outbreak). We hypothesized greater N cycling responses in Douglas-fir due to higher overall N stocks. Undisturbed Douglas-fir stands had greater litter N pools, soil N, and net N mineralization than lodgepole pine. Several responses to disturbance were similar between forest types, including a pulse of N-enriched litter, doubling of soil N availability, 30-50 % increase in understory cover, and 20 % increase in foliar N concentration of unattacked trees. However, the response of some ecosystem properties notably varied by host forest type. Soil temperature was unaffected in Douglas-fir, but lowered in lodgepole pine. Fresh foliar %N was uncorrelated with net N mineralization in Douglas-fir, but positively correlated in lodgepole pine. Though soil ammonium and nitrate, net N mineralization, and net nitrification all doubled, they remained low in both forest types (<6 μg N g soil(-1) NH(4) (+)or NO(3) (-); <25 μg N g soil(-1) year(-1) net N mineralization; <8 μg N g soil(-1) year(-1) net nitrification). Results suggest that beetle disturbance affected litter and soil N cycling similarly in each forest type, despite substantial differences in pre-disturbance biogeochemistry. In contrast, soil temperature and soil N-foliar N linkages differed between host forest types. This result suggests that disturbance type may be a better predictor of litter and soil N responses than forest type due to similar disturbance mechanisms and disturbance legacies

  16. Fire Severity Controlled Susceptibility to a 1940s Spruce Beetle Outbreak in Colorado, USA.

    PubMed

    Kulakowski, Dominik; Veblen, Thomas T; Bebi, Peter

    2016-01-01

    The frequency, magnitude, and size of forest disturbances are increasing globally. Much recent research has focused on how the occurrence of one disturbance may affect susceptibility to subsequent disturbances. While much has been learned about such linked disturbances, the strength of the interactions is likely to be contingent on the severity of disturbances as well as climatic conditions, both of which can affect disturbance intensity and tree resistance to disturbances. Subalpine forests in western Colorado were affected by extensive and severe wildfires in the late 19th century and an extensive and severe outbreak of spruce beetle (Dendroctonus rufipennis) in the 1940s. Previous research found that most, but not all, of the stands that burned and established following the late 19th century fires were not susceptible to the 1940s outbreak as beetles preferentially attack larger trees and stands in advanced stages of development. However, previous research also left open the possibility that some stands that burned and established following the 19th century fires may have been attacked during the 1940s outbreak. Understanding how strongly stand structure, as shaped by disturbances of varying severity, affected susceptibility to past outbreaks is important to provide a baseline for assessing the degree to which recent climate change may be relaxing the preferences of beetles for larger trees and for stands in latter stages of structural development and thereby changing the nature of linked disturbances. Here, dendroecological methods were used to study disturbance history and tree age of stands in the White River National Forest in Western Colorado that were identified in historical documents or remotely-sensed images as having burned in the 19th century and having been attacked by spruce beetle in the 1940s. Dendroecological reconstructions indicate that in young post-fire stands only old remnant trees that survived the otherwise stand-replacing fires were

  17. Fire Severity Controlled Susceptibility to a 1940s Spruce Beetle Outbreak in Colorado, USA

    PubMed Central

    Kulakowski, Dominik; Veblen, Thomas T.; Bebi, Peter

    2016-01-01

    The frequency, magnitude, and size of forest disturbances are increasing globally. Much recent research has focused on how the occurrence of one disturbance may affect susceptibility to subsequent disturbances. While much has been learned about such linked disturbances, the strength of the interactions is likely to be contingent on the severity of disturbances as well as climatic conditions, both of which can affect disturbance intensity and tree resistance to disturbances. Subalpine forests in western Colorado were affected by extensive and severe wildfires in the late 19th century and an extensive and severe outbreak of spruce beetle (Dendroctonus rufipennis) in the 1940s. Previous research found that most, but not all, of the stands that burned and established following the late 19th century fires were not susceptible to the 1940s outbreak as beetles preferentially attack larger trees and stands in advanced stages of development. However, previous research also left open the possibility that some stands that burned and established following the 19th century fires may have been attacked during the 1940s outbreak. Understanding how strongly stand structure, as shaped by disturbances of varying severity, affected susceptibility to past outbreaks is important to provide a baseline for assessing the degree to which recent climate change may be relaxing the preferences of beetles for larger trees and for stands in latter stages of structural development and thereby changing the nature of linked disturbances. Here, dendroecological methods were used to study disturbance history and tree age of stands in the White River National Forest in Western Colorado that were identified in historical documents or remotely-sensed images as having burned in the 19th century and having been attacked by spruce beetle in the 1940s. Dendroecological reconstructions indicate that in young post-fire stands only old remnant trees that survived the otherwise stand-replacing fires were

  18. Fire Severity Controlled Susceptibility to a 1940s Spruce Beetle Outbreak in Colorado, USA.

    PubMed

    Kulakowski, Dominik; Veblen, Thomas T; Bebi, Peter

    2016-01-01

    The frequency, magnitude, and size of forest disturbances are increasing globally. Much recent research has focused on how the occurrence of one disturbance may affect susceptibility to subsequent disturbances. While much has been learned about such linked disturbances, the strength of the interactions is likely to be contingent on the severity of disturbances as well as climatic conditions, both of which can affect disturbance intensity and tree resistance to disturbances. Subalpine forests in western Colorado were affected by extensive and severe wildfires in the late 19th century and an extensive and severe outbreak of spruce beetle (Dendroctonus rufipennis) in the 1940s. Previous research found that most, but not all, of the stands that burned and established following the late 19th century fires were not susceptible to the 1940s outbreak as beetles preferentially attack larger trees and stands in advanced stages of development. However, previous research also left open the possibility that some stands that burned and established following the 19th century fires may have been attacked during the 1940s outbreak. Understanding how strongly stand structure, as shaped by disturbances of varying severity, affected susceptibility to past outbreaks is important to provide a baseline for assessing the degree to which recent climate change may be relaxing the preferences of beetles for larger trees and for stands in latter stages of structural development and thereby changing the nature of linked disturbances. Here, dendroecological methods were used to study disturbance history and tree age of stands in the White River National Forest in Western Colorado that were identified in historical documents or remotely-sensed images as having burned in the 19th century and having been attacked by spruce beetle in the 1940s. Dendroecological reconstructions indicate that in young post-fire stands only old remnant trees that survived the otherwise stand-replacing fires were

  19. Beetle wings are inflatable origami

    NASA Astrophysics Data System (ADS)

    Chen, Rui; Ren, Jing; Ge, Siqin; Hu, David

    2015-11-01

    Beetles keep their wings folded and protected under a hard shell. In times of danger, they must unfold them rapidly in order for them to fly to escape. Moreover, they must do so across a range of body mass, from 1 mg to 10 grams. How can they unfold their wings so quickly? We use high-speed videography to record wing unfolding times, which we relate to the geometry of the network of blood vessels in the wing. Larger beetles have longer unfolding times. Modeling of the flow of blood through the veins successfully accounts for the wing unfolding speed of large beetles. However, smaller beetles have anomalously short unfolding times, suggesting they have lower blood viscosity or higher driving pressure. The use of hydraulics to unfold complex objects may have implications in the design of micro-flying air vehicles.

  20. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus.

    PubMed

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M; Erbilgin, Nadir

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle's historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects. PMID:27583820

  1. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus.

    PubMed

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M; Erbilgin, Nadir

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle's historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects.

  2. Persistent pods of the tree Acacia caven: a natural refuge for diverse insects including Bruchid beetles and the parasitoids Trichogrammatidae, Pteromalidae and Eulophidae

    PubMed Central

    Rojas-Rousse, D.

    2006-01-01

    The persistent pods of the tree, Acacia caven that do not fall from the tree provide opportunities for the appearance of a diverse group of insects the following season. Such pods collected during the spring of 1999 in Chile were indehiscent with highly sclerified pod walls. In contrast, persistent pods collected in Uruguay after a wet winter and spring (2002) were partially dehiscent, inducing the deterioration of the woody pods, and consequently exposing the seeds. These persistent pods are a natural refuge for insect species, namely two bruchid beetles (Pseudopachymeria spinipes, Stator furcatus), one scolytidae (Dendroctonus sp), lepidopterous larvae, ant colonies (Camponotus sp), one species of oophagous parasitoid (Uscana espinae group senex), the gregarious larval-pupae parasitoid Monoksa dorsiplana (Pteromalidae) and two species of Horismenus spp.(Eulophidae). The patriline of M. dorsiplana is frequently formed by 1 son + 7 daughters. PMID:19537971

  3. Densities of breeding birds and changes in vegetation in an alaskan boreal forest following a massive disturbance by spruce beetles

    USGS Publications Warehouse

    Matsuoka, S.M.; Handel, C.M.; Ruthrauff, D.R.

    2001-01-01

    We examined bird and plant communities among forest stands with different levels of spruce mortality following a large outbreak of spruce beetles (Dendroctonus rufipennis (Kirby)) in the Copper River Basin, Alaska. Spruce beetles avoided stands with black spruce (Picea mariana) and selectively killed larger diameter white spruce (Picea glauca), thereby altering forest structure and increasing the dominance of black spruce in the region. Alders (Alnus sp.) and crowberry (Empetrum nigrum) were more abundant in areas with heavy spruce mortality, possibly a response to the death of overstory spruce. Grasses and herbaceous plants did not proliferate as has been recorded following outbreaks in more coastal Alaskan forests. Two species closely tied to coniferous habitats, the tree-nesting Ruby-crowned Kinglet (Regulus calendula) and the red squirrel (Tamiasciurus hudsonicus), a major nest predator, were less abundant in forest stands with high spruce mortality than in low-mortality stands. Understory-nesting birds as a group were more abundant in forest stands with high levels of spruce mortality, although the response of individual bird species to tree mortality was variable. Birds breeding in stands with high spruce mortality likely benefited reproductively from lower squirrel densities and a greater abundance of shrubs to conceal nests from predators.

  4. Changes In Snowmelt Timing In Response To Pine Beetle Infestation In Lodgepole Pines In The Colorado Rockies

    NASA Astrophysics Data System (ADS)

    Pugh, E.; Tilton, E. S.

    2008-12-01

    Since 1996, roughly 1.5 million acres of lodgepole pine forest in Colorado have been infested by mountain pine beetles (Dendroctonus ponderosae). We measured physical snowpack properties (depth, density, and temperature) under stands of both living and dead lodgepole pines in the Colorado Rockies. This data allowed us to investigate the effect of increased forest canopy transmittance due to tree death on potential advances in the annual hydrograph. We compared snow accumulation and melt on north-facing and south- facing slopes at an elevation of approximately 3000m. As expected, topography-dominated solar forcing is the chief factor in snowmelt: snow on south-facing slopes melted earlier in the season than north-facing slopes. Comparing stands of dead and live trees within topographic zones revealed a few dramatic differences: snow water equivalent was lower and mean snowpack temperature was warmer in dead lodgepole pine stands. Temperature timeseries from within the snowpack suggest that snow in dead tree stands became isothermal sooner than snow in living tree stands. Together these show that there was indeed earlier snowmelt in lodgepole pine forest regions infested with mountain pine beetle. Earlier snowmelt will likely cause peak snowmelt discharge to occur sooner.

  5. The bioconversion of mountain pine beetle-killed lodgepole pine to fuel ethanol using the organosolv process.

    PubMed

    Pan, Xuejun; Xie, Dan; Yu, Richard W; Saddler, Jack N

    2008-09-01

    Lodgepole pine (Pinus contorta) killed by mountain pine beetle (Dendroctonus ponderosae) (BLP) was compared with healthy lodgepole pine (HLP) for bioconversion to ethanol and high-value co-products. The BLP and HLP chips were pretreated using an ethanol organosolv process at a variety of severities. It was shown that the BLP was easier to pretreat and delignify than were the HLP chips. The resulting pretreated BLP substrate had a lower residual lignin, lower degree of polymerization of cellulose, lower cellulose crystallinity, smaller fiber size and thereby a better enzymatic hydrolysability than did the HLP substrates. However, under the same conditions, the BLP showed lower substrate yield and cellulose recovery than did the HLP, which likely resulted from the excessive hydrolysis and subsequent decomposition of the cellulose and hemicellulose during the pretreatment. The BLP wood yielded more ethanol organosolv lignin than was obtained with the HLP material. The HLP lignin had a lower molecular weight and narrower distribution than did the BLP lignin. It appears that the beetle killed LP is more receptive to organosolv pretreatment other than a slightly lower recovery of carbohydrates.

  6. Charles Darwin, beetles and phylogenetics.

    PubMed

    Beutel, Rolf G; Friedrich, Frank; Leschen, Richard A B

    2009-11-01

    Here, we review Charles Darwin's relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in "The Descent of Man". During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig's new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data. This has

  7. Charles Darwin, beetles and phylogenetics

    NASA Astrophysics Data System (ADS)

    Beutel, Rolf G.; Friedrich, Frank; Leschen, Richard A. B.

    2009-11-01

    Here, we review Charles Darwin’s relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in “The Descent of Man”. During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig’s new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data

  8. Charles Darwin, beetles and phylogenetics.

    PubMed

    Beutel, Rolf G; Friedrich, Frank; Leschen, Richard A B

    2009-11-01

    Here, we review Charles Darwin's relation to beetles and developments in coleopteran systematics in the last two centuries. Darwin was an enthusiastic beetle collector. He used beetles to illustrate different evolutionary phenomena in his major works, and astonishingly, an entire sub-chapter is dedicated to beetles in "The Descent of Man". During his voyage on the Beagle, Darwin was impressed by the high diversity of beetles in the tropics, and he remarked that, to his surprise, the majority of species were small and inconspicuous. However, despite his obvious interest in the group, he did not get involved in beetle taxonomy, and his theoretical work had little immediate impact on beetle classification. The development of taxonomy and classification in the late nineteenth and earlier twentieth century was mainly characterised by the exploration of new character systems (e.g. larval features and wing venation). In the mid-twentieth century, Hennig's new methodology to group lineages by derived characters revolutionised systematics of Coleoptera and other organisms. As envisioned by Darwin and Ernst Haeckel, the new Hennigian approach enabled systematists to establish classifications truly reflecting evolution. Roy A. Crowson and Howard E. Hinton, who both made tremendous contributions to coleopterology, had an ambivalent attitude towards the Hennigian ideas. The Mickoleit school combined detailed anatomical work with a classical Hennigian character evaluation, with stepwise tree building, comparatively few characters and a priori polarity assessment without explicit use of the outgroup comparison method. The rise of cladistic methods in the 1970s had a strong impact on beetle systematics. Cladistic computer programs facilitated parsimony analyses of large data matrices, mostly morphological characters not requiring detailed anatomical investigations. Molecular studies on beetle phylogeny started in the 1990s with modest taxon sampling and limited DNA data. This has

  9. A dynamical model for bark beetle outbreaks.

    PubMed

    Křivan, Vlastimil; Lewis, Mark; Bentz, Barbara J; Bewick, Sharon; Lenhart, Suzanne M; Liebhold, Andrew

    2016-10-21

    Tree-killing bark beetles are major disturbance agents affecting coniferous forest ecosystems. The role of environmental conditions on driving beetle outbreaks is becoming increasingly important as global climatic change alters environmental factors, such as drought stress, that, in turn, govern tree resistance. Furthermore, dynamics between beetles and trees are highly nonlinear, due to complex aggregation behaviors exhibited by beetles attacking trees. Models have a role to play in helping unravel the effects of variable tree resistance and beetle aggregation on bark beetle outbreaks. In this article we develop a new mathematical model for bark beetle outbreaks using an analogy with epidemiological models. Because the model operates on several distinct time scales, singular perturbation methods are used to simplify the model. The result is a dynamical system that tracks populations of uninfested and infested trees. A limiting case of the model is a discontinuous function of state variables, leading to solutions in the Filippov sense. The model assumes an extensive seed-bank so that tree recruitment is possible even if trees go extinct. Two scenarios are considered for immigration of new beetles. The first is a single tree stand with beetles immigrating from outside while the second considers two forest stands with beetle dispersal between them. For the seed-bank driven recruitment rate, when beetle immigration is low, the forest stand recovers to a beetle-free state. At high beetle immigration rates beetle populations approach an endemic equilibrium state. At intermediate immigration rates, the model predicts bistability as the forest can be in either of the two equilibrium states: a healthy forest, or a forest with an endemic beetle population. The model bistability leads to hysteresis. Interactions between two stands show how a less resistant stand of trees may provide an initial toe-hold for the invasion, which later leads to a regional beetle outbreak in the

  10. A dynamical model for bark beetle outbreaks.

    PubMed

    Křivan, Vlastimil; Lewis, Mark; Bentz, Barbara J; Bewick, Sharon; Lenhart, Suzanne M; Liebhold, Andrew

    2016-10-21

    Tree-killing bark beetles are major disturbance agents affecting coniferous forest ecosystems. The role of environmental conditions on driving beetle outbreaks is becoming increasingly important as global climatic change alters environmental factors, such as drought stress, that, in turn, govern tree resistance. Furthermore, dynamics between beetles and trees are highly nonlinear, due to complex aggregation behaviors exhibited by beetles attacking trees. Models have a role to play in helping unravel the effects of variable tree resistance and beetle aggregation on bark beetle outbreaks. In this article we develop a new mathematical model for bark beetle outbreaks using an analogy with epidemiological models. Because the model operates on several distinct time scales, singular perturbation methods are used to simplify the model. The result is a dynamical system that tracks populations of uninfested and infested trees. A limiting case of the model is a discontinuous function of state variables, leading to solutions in the Filippov sense. The model assumes an extensive seed-bank so that tree recruitment is possible even if trees go extinct. Two scenarios are considered for immigration of new beetles. The first is a single tree stand with beetles immigrating from outside while the second considers two forest stands with beetle dispersal between them. For the seed-bank driven recruitment rate, when beetle immigration is low, the forest stand recovers to a beetle-free state. At high beetle immigration rates beetle populations approach an endemic equilibrium state. At intermediate immigration rates, the model predicts bistability as the forest can be in either of the two equilibrium states: a healthy forest, or a forest with an endemic beetle population. The model bistability leads to hysteresis. Interactions between two stands show how a less resistant stand of trees may provide an initial toe-hold for the invasion, which later leads to a regional beetle outbreak in the

  11. Biological pest control in beetle agriculture.

    PubMed

    Aanen, Duur K; Slippers, Bernard; Wingfield, Michael J

    2009-05-01

    Bark beetles are among the most destructive tree pests on the planet. Their symbiosis with fungi has consequently been studied extensively for more than a century. A recent study has identified actinomycete bacteria that are associated with the southern pine beetle and produce specific antibiotics against an antagonist of the beetles' mutualistic fungus. In addition to highlighting the ecological complexity of bark-beetle-microbial symbioses, this work reveals a potential source of novel antibiotics.

  12. Synergistic blends of monoterpenes for aggregation pheromones of the mountain pine beetle (Coleoptera: Curculionidae).

    PubMed

    Borden, John H; Pureswaran, Deepa S; Lafontaine, Jean Pierre

    2008-08-01

    The superiority of the host monoterpene myrcene as a synergist for trans-verbenol and exo-brevicomin, aggregation pheromone components of the mountain pine beetle, Dendroctonus ponderosae Hopkins (Coleoptera: Curculionidae), suggests that the ancestral host of the mountain pine beetle is a pine rich in myrcene. A field trapping experiment in British Columbia testing reconstituted bole oleoresin of whitebark pine, Pinus albicaulis Engelmann, composed of mainly myrcene (20.7%), terpinolene (6.8%), and 3-carene (61.9%) showed it to be a better pheromone synergist than reconstituted bole oleoresin of lodgepole pine, Pinus contorta variety latifolia Engelmann, which contained only 2.7, 1.0, and 6.0%, respectively, of the above-mentioned three compounds. In the same experiment myrcene alone was the best synergist. In subsequent experiments, testing myrcene, terpinolene and 3-carene alone and in all possible binary and ternary combinations, a 50:50 blend of myrcene and terpinolene released at the same rate as either compound alone generally resulted in trap catches approximately 3 times higher than with myrcene as a synergist. This result held as long as the terpinolene was free of contaminants, and the traps were in the open, well away from potential interference of semiochemicals emitted by newly attacked trees. 3-Carene seemed to be inert or slightly inhibitory. No single monoterpene tested alone or in binary or ternary combination in the absence of pheromones was attractive. There was no effect of doubling or tripling the release rate of myrcene or terpinolene. In five of nine experiments, adding terpinolene to myrcene caused a significant increase in the percentage of female mountain pine beetles captured. Among host pines, the presence of highly synergistic monoterpenes at various levels in combination with other monoterpenes that are apparently either inert or inhibitory could account for different degrees of pheromone synergism, and thus host preference. The

  13. Spatiotemporal patterns of mountain pine beetle activity in the southern Rocky Mountains.

    PubMed

    Chapman, Teresa B; Veblen, Thomas T; Schoennagel, Tania

    2012-10-01

    The current mountain pine beetle (MPB; Dendroctonus ponderosae) outbreak in the southern Rocky Mountains has impacted approximately 750 000 ha of forest. Weather and habitat heterogeneity influence forest insect population dynamics at multiple spatial and temporal scales. Comparison of forest insect population dynamics in two principal host species may elucidate the relative contribution of weather and landscape factors in initiating and driving extensive outbreaks. To investigate potential drivers of the current MPB outbreak, we compared broadscale spatiotemporal patterns of MPB activity in lodgepole pine (Pinus contorta) and ponderosa pine (Pinus ponderosa) from 1996 to 2010 in Colorado and southern Wyoming with regional weather fluctuations, and then tracked the annual meso-scale progression of the epidemic in lodgepole pine with respect to weather, topographic, previous MPB activity, and forest stand attributes. MPB activity in lodgepole pine compared to ponderosa pine showed higher magnitude and extent of spatial synchrony. Warm temperatures and low annual precipitation favorable to beetle populations showed high regional synchrony across areas of both pine species, suggesting that habitat interacts with weather in synchronizing MPB populations. Cluster analysis of time series patterns identified multiple, disjunct locations of incipient MPB activity (epicenters) in lodgepole pine, which overlapped an earlier 1980s MPB outbreak, and suggests a regional trigger (drought) across this homogenous forest type. Negative departures from mean annual precipitation played a key role in subsequent spread of MPB outbreak. Development of the outbreak was also associated with lower elevations, greater dominance by lodgepole pine, stands of larger tree size, and stands with higher percentage canopy cover. After epidemic levels of MPB activity were attained, MPB activity was less strongly associated with stand and weather variables. These results emphasize the importance of

  14. Spatiotemporal patterns of mountain pine beetle activity in the southern Rocky Mountains.

    PubMed

    Chapman, Teresa B; Veblen, Thomas T; Schoennagel, Tania

    2012-10-01

    The current mountain pine beetle (MPB; Dendroctonus ponderosae) outbreak in the southern Rocky Mountains has impacted approximately 750 000 ha of forest. Weather and habitat heterogeneity influence forest insect population dynamics at multiple spatial and temporal scales. Comparison of forest insect population dynamics in two principal host species may elucidate the relative contribution of weather and landscape factors in initiating and driving extensive outbreaks. To investigate potential drivers of the current MPB outbreak, we compared broadscale spatiotemporal patterns of MPB activity in lodgepole pine (Pinus contorta) and ponderosa pine (Pinus ponderosa) from 1996 to 2010 in Colorado and southern Wyoming with regional weather fluctuations, and then tracked the annual meso-scale progression of the epidemic in lodgepole pine with respect to weather, topographic, previous MPB activity, and forest stand attributes. MPB activity in lodgepole pine compared to ponderosa pine showed higher magnitude and extent of spatial synchrony. Warm temperatures and low annual precipitation favorable to beetle populations showed high regional synchrony across areas of both pine species, suggesting that habitat interacts with weather in synchronizing MPB populations. Cluster analysis of time series patterns identified multiple, disjunct locations of incipient MPB activity (epicenters) in lodgepole pine, which overlapped an earlier 1980s MPB outbreak, and suggests a regional trigger (drought) across this homogenous forest type. Negative departures from mean annual precipitation played a key role in subsequent spread of MPB outbreak. Development of the outbreak was also associated with lower elevations, greater dominance by lodgepole pine, stands of larger tree size, and stands with higher percentage canopy cover. After epidemic levels of MPB activity were attained, MPB activity was less strongly associated with stand and weather variables. These results emphasize the importance of

  15. Mapping mountain pine beetle mortality through growth trend analysis of time-series landsat data

    USGS Publications Warehouse

    Liang, Lu; Chen, Yanlei; Hawbaker, Todd J.; Zhu, Zhi-Liang; Gong, Peng

    2014-01-01

    Disturbances are key processes in the carbon cycle of forests and other ecosystems. In recent decades, mountain pine beetle (MPB; Dendroctonus ponderosae) outbreaks have become more frequent and extensive in western North America. Remote sensing has the ability to fill the data gaps of long-term infestation monitoring, but the elimination of observational noise and attributing changes quantitatively are two main challenges in its effective application. Here, we present a forest growth trend analysis method that integrates Landsat temporal trajectories and decision tree techniques to derive annual forest disturbance maps over an 11-year period. The temporal trajectory component successfully captures the disturbance events as represented by spectral segments, whereas decision tree modeling efficiently recognizes and attributes events based upon the characteristics of the segments. Validated against a point set sampled across a gradient of MPB mortality, 86.74% to 94.00% overall accuracy was achieved with small variability in accuracy among years. In contrast, the overall accuracies of single-date classifications ranged from 37.20% to 75.20% and only become comparable with our approach when the training sample size was increased at least four-fold. This demonstrates that the advantages of this time series work flow exist in its small training sample size requirement. The easily understandable, interpretable and modifiable characteristics of our approach suggest that it could be applicable to other ecoregions.

  16. Large-scale climatic patterns and area affected by mountain pine beetle in British Columbia, Canada

    NASA Astrophysics Data System (ADS)

    Macias Fauria, Marc; Johnson, E. A.

    2009-03-01

    We present evidence of high spatial synchrony in an area affected by mountain pine beetle (MPB, Dendroctonus ponderosae) across large distances in British Columbia, Canada, in a study of a spatially explicit database of an area affected by MPB-caused tree mortality for the period 1959-2002. We further show that large-scale climatic patterns (Pacific Decadal Oscillation (PDO) and, to a lesser degree, Arctic Oscillation (AO)) are strongly related to the observed MPB synchrony, and that they probably operate through controlling the frequency of extreme cold winter temperatures that affect MPB larvae survival. A smaller portion of the data's variability is linked to the onset of the two largest outbreaks in the studied period and might be attributed to dispersal from outbreak-prone areas or else to differences in microhabitat (e.g., host availability) in these regions. The onset of a warm PDO phase in 1976 favored MPB outbreaks by reducing the occurrence of extremely low winter temperatures province-wide. Likewise, the exceptionally high and persistent AO values of the late 1980s and 1990s enhanced MPB activity in the southern and northern parts of the region. Summer warmth cannot be discarded as an important agent at smaller scales.

  17. Assessing the effects of changing climate on mountain pine beetle dynamics

    SciTech Connect

    Logan, J.A.; Bentz, B.J.; Bolstad, P.V.; Perkins, D.L.

    1995-12-31

    In general terms, global climate warming will result in exacerbated insect pest problems. This is not to say, however, that the effects of every current pest species will increase under global warming. Projections regarding a particular pest species need to be made on a case-by-case basis. For example, mountain pine beetle (MPB) populations (Dendroctonus pondersae Hopkins), would benefit from global warming due to reduced winter mortality. Conversely, global warming may interfere with the maintaining of an appropriate seasonality for this non-diapausing species. Addressing such species response to modification of a basic ecological driving variable such as climate is a complex issue. Difficulty in dealing with this issue is further compounded by the fact that direct evidence is lacking and system level experimental manipulation is prohibitively expensive. The authors first describe in general terms the climatic adapted ecology of MPB and a computer model designed to represent important aspects of that ecology. Next they describe the important habitat component of mountain weather on MPB population performance and a landscape-level approach to modeling this critical driving variable. Finally, they describe a research application that uses these models to evaluate the potential of MPB outbreaks as an indication of forest health in high-elevation pine forests.

  18. Mountain pine beetle develops an unprecedented summer generation in response to climate warming.

    PubMed

    Mitton, Jeffry B; Ferrenberg, Scott M

    2012-05-01

    The mountain pine beetle (MPB; Dendroctonus ponderosae) is native to western North America, attacks most trees of the genus Pinus, and periodically erupts in epidemics. The current epidemic of the MPB is an order of magnitude larger than any previously recorded, reaching trees at higher elevation and latitude than ever before. Here we show that after 2 decades of air-temperature increases in the Colorado Front Range, the MPB flight season begins more than 1 month earlier than and is approximately twice as long as the historically reported season. We also report, for the first time, that the life cycle in some broods has increased from one to two generations per year. Because MPBs do not diapause and their development is controlled by temperature, they are responding to climate change through faster development. The expansion of the MPB into previously inhospitable environments, combined with the measured ability to increase reproductive output in such locations, indicates that the MPB is tracking climate change, exacerbating the current epidemic.

  19. Are stag beetles fungivorous?

    PubMed

    Tanahashi, Masahiko; Matsushita, Norihisa; Togashi, Katsumi

    2009-11-01

    Stag beetle larvae generally feed on decaying wood; however, it was unknown whether they can use wood-rotting fungi alone as food. Here, to clarify this, newly hatched larvae of Dorcus rectus (Motschulsky) (Coleoptera: Lucanidae) were reared for 14 days on artificial diets containing a fixed amount of freeze-dried mycelia of the following fungi: Bjerkandera adusta, Trametes versicolor, Pleurotus ostreatus, and Fomitopsis pinicola. The mean incremental gain in larval body mass was greatest on diets containing B. adusta, followed by T. versicolor, P. ostreatus, and F. pinicola. The growth rate of body mass correlated positively with mycelial nitrogen content of the different fungi. It also correlated positively with the mycelial content of B. adusta in the diet. Addition of antibiotics to diets with mycelia nearly halved larval growth, indicating that larvae were able to use fungal mycelia as food without the assistance of associated microbes although the microbes positively affected larval growth. Four newly hatched larvae reared on artificial diets containing B. adusta mycelia developed to the second instar in 21-34 days; and one developed to the third (=final) instar. This study provides evidence that fungi may constitute the bulk of the diet of D. rectus larvae. PMID:19607834

  20. Rapid Induction of Multiple Terpenoid Groups by Ponderosa Pine in Response to Bark Beetle-Associated Fungi.

    PubMed

    Keefover-Ring, Ken; Trowbridge, Amy; Mason, Charles J; Raffa, Kenneth F

    2016-01-01

    Ponderosa pine (Pinus ponderosa) is a major and widely distributed component of conifer biomes in western North America and provides substantial ecological and economic benefits. This tree is exposed to several tree-killing bark beetle-microbial complexes, including the mountain pine beetle (Dendroctonus ponderosae) and the phytopathogenic fungus Grosmannia clavigera that it vectors, which are among the most important. Induced responses play a crucial role in conifer defenses, yet these have not been reported in ponderosa pine. We compared concentrations of terpenes and a phenylpropanoid, two phytochemical classes with strong effects against bark beetles and their symbionts, in constitutive phloem tissue and in tissue following mechanical wounding or simulated D. ponderosae attack (mechanical wounding plus inoculation with G. clavigera). We also tested whether potential induced responses were localized or systemic. Ponderosa pines showed pronounced induced defenses to inoculation, increasing their total phloem concentrations of monoterpenes 22.3-fold, sesquiterpenes 56.7-fold, and diterpenes 34.8-fold within 17 days. In contrast, responses to mechanical wounding alone were only 5.2, 11.3, and 7.7-fold, respectively. Likewise, the phenylpropanoid estragole (4-allyanisole) rose to 19.1-fold constitutive levels after simulated attack but only 4.4-fold after mechanical wounding. Overall, we found no evidence of systemic induction after 17 days, which spans most of this herbivore's narrow peak attack period, as significant quantitative and compositional changes within and between terpenoid groups were localized to the wound site. Implications to the less frequent exploitation of ponderosa than lodgepole pine by D. ponderosae, and potential advantages of rapid localized over long-term systemic responses in this system, are discussed.

  1. Integrating models to investigate critical phenological overlaps in complex ecological interactions: the mountain pine beetle-fungus symbiosis.

    PubMed

    Addison, Audrey; Powell, James A; Bentz, Barbara J; Six, Diana L

    2015-03-01

    The fates of individual species are often tied to synchronization of phenology, however, few methods have been developed for integrating phenological models involving linked species. In this paper, we focus on mountain pine beetle (MPB, Dendroctonus ponderosae) and its two obligate mutualistic fungi, Grosmannia clavigera and Ophiostoma montium. Growth rates of all three partners are driven by temperature, and their idiosyncratic responses affect interactions at important life stage junctures. One critical phase for MPB-fungus symbiosis occurs just before dispersal of teneral (new) adult beetles, when fungi are acquired and transported in specialized structures (mycangia). Before dispersal, fungi must capture sufficient spatial resources within the tree to ensure contact with teneral adults and get packed into mycangia. Mycangial packing occurs at an unknown time during teneral feeding. We adapt thermal models predicting fungal growth and beetle development to predict overlap between the competing fungi and MPB teneral adult feeding windows and emergence. We consider a spectrum of mycangial packing strategies and describe them in terms of explicit functions with unknown parameters. Rates of growth are fixed by laboratory data, the unknown parameters describing various packing strategies, as well as the degree to which mycangial growth is slowed in woody tissues as compared to agar, are determined by maximum likelihood and two years of field observations. At the field location used, the most likely fungus acquisition strategy for MPB was packing mycangia just prior to emergence. Estimated model parameters suggested large differences in the relative growth rates of the two fungi in trees at the study site, with the most likely model estimating that G. clavigera grew approximately twenty-five times faster than O. montium under the bark, which is completely unexpected in comparison with observed fungal growth on agar.

  2. Integrating models to investigate critical phenological overlaps in complex ecological interactions: the mountain pine beetle-fungus symbiosis.

    PubMed

    Addison, Audrey; Powell, James A; Bentz, Barbara J; Six, Diana L

    2015-03-01

    The fates of individual species are often tied to synchronization of phenology, however, few methods have been developed for integrating phenological models involving linked species. In this paper, we focus on mountain pine beetle (MPB, Dendroctonus ponderosae) and its two obligate mutualistic fungi, Grosmannia clavigera and Ophiostoma montium. Growth rates of all three partners are driven by temperature, and their idiosyncratic responses affect interactions at important life stage junctures. One critical phase for MPB-fungus symbiosis occurs just before dispersal of teneral (new) adult beetles, when fungi are acquired and transported in specialized structures (mycangia). Before dispersal, fungi must capture sufficient spatial resources within the tree to ensure contact with teneral adults and get packed into mycangia. Mycangial packing occurs at an unknown time during teneral feeding. We adapt thermal models predicting fungal growth and beetle development to predict overlap between the competing fungi and MPB teneral adult feeding windows and emergence. We consider a spectrum of mycangial packing strategies and describe them in terms of explicit functions with unknown parameters. Rates of growth are fixed by laboratory data, the unknown parameters describing various packing strategies, as well as the degree to which mycangial growth is slowed in woody tissues as compared to agar, are determined by maximum likelihood and two years of field observations. At the field location used, the most likely fungus acquisition strategy for MPB was packing mycangia just prior to emergence. Estimated model parameters suggested large differences in the relative growth rates of the two fungi in trees at the study site, with the most likely model estimating that G. clavigera grew approximately twenty-five times faster than O. montium under the bark, which is completely unexpected in comparison with observed fungal growth on agar. PMID:25556687

  3. Beetle Kill Wall at NREL

    SciTech Connect

    2010-01-01

    When it comes to designing an interior decorative feature for one of the most energy efficient office buildings in the world, very few would consider bringing in a beetle to do the job. But thats what happened at the U.S. Department of Energy's (DOE) Research Support Facility (RSF) located on the National Renewable Energy Laboratory (NREL) campus.In June, the RSF will become home to more than 800 workers from DOE and NREL and building visitors will be greeted with a soaring, two-story high wall entirely covered with wood harvested from the bark beetle infestation that has killed millions of pine trees in the Western U.S. But, the use of beetle kill wood is just one example of the resources being leveraged to make the RSF a model for sustainability and one more step toward NRELs goal to be a net zero energy campus.

  4. Beetle Kill Wall at NREL

    ScienceCinema

    None

    2016-07-12

    When it comes to designing an interior decorative feature for one of the most energy efficient office buildings in the world, very few would consider bringing in a beetle to do the job. But thats what happened at the U.S. Department of Energy's (DOE) Research Support Facility (RSF) located on the National Renewable Energy Laboratory (NREL) campus.In June, the RSF will become home to more than 800 workers from DOE and NREL and building visitors will be greeted with a soaring, two-story high wall entirely covered with wood harvested from the bark beetle infestation that has killed millions of pine trees in the Western U.S. But, the use of beetle kill wood is just one example of the resources being leveraged to make the RSF a model for sustainability and one more step toward NRELs goal to be a net zero energy campus.

  5. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    PubMed

    Agne, Michelle C; Shaw, David C; Woolley, Travis J; Queijeiro-Bolaños, Mónica E

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to

  6. Impact of mountain pine beetle outbreaks on forest albedo and radiative forcing, as derived from Moderate Resolution Imaging Spectroradiometer, Rocky Mountains, USA

    NASA Astrophysics Data System (ADS)

    Vanderhoof, M.; Williams, C. A.; Ghimire, B.; Rogan, J.

    2013-12-01

    pine beetle (Dendroctonus ponderosae) outbreaks in North America are widespread and have potentially large-scale impacts on albedo and associated radiative forcing. Mountain pine beetle outbreaks in Colorado and southern Wyoming have resulted in persistent and significant increases in both winter albedo (change peaked 10 years post outbreak at 0.06 ± 0.01 and 0.05 ± 0.01, in lodgepole pine (Pinus contorta) and ponderosa pine (Pinus ponderosa) stands, respectively) and spring albedo (change peaked 10 years post outbreak at 0.06 ± 0.01 and 0.04 ± 0.01, in lodgepole pine and ponderosa pine stands, respectively). Instantaneous top-of-atmosphere radiative forcing peaked for both lodgepole pine and ponderosa pine stands in winter at 10 years post outbreak at -1.7 ± 0.2 W m-2 and -1.4 ± 0.2 W m-2, respectively. The persistent increase in albedo with time since mountain pine beetle disturbance combined with the continued progression of the attack across the landscape from 1994-2011 resulted in an exponential increase in winter and annual radiative cooling (MW) over time. In 2011 the rate of radiative forcing within the study area reached -982.7 ± 139.0 MW, -269.8 ± 38.2 MW, -31.1 ± 4.4 MW, and -147.8 ± 20.9 MW in winter, spring, summer, and fall, respectively. An increase in radiative cooling has the potential to decrease sensible and/or latent heat flux by reducing available energy. Such changes could affect current mountain pine beetle outbreaks which are influenced by climatic conditions.

  7. Fatty Acid Composition of Novel Host Jack Pine Do Not Prevent Host Acceptance and Colonization by the Invasive Mountain Pine Beetle and Its Symbiotic Fungus

    PubMed Central

    Ishangulyyeva, Guncha; Najar, Ahmed; Curtis, Jonathan M.

    2016-01-01

    Fatty acids are major components of plant lipids and can affect growth and development of insect herbivores. Despite a large literature examining the roles of fatty acids in conifers, relatively few studies have tested the effects of fatty acids on insect herbivores and their microbial symbionts. Particularly, whether fatty acids can affect the suitability of conifers for insect herbivores has never been studied before. Thus, we evaluated if composition of fatty acids impede or facilitate colonization of jack pine (Pinus banksiana) by the invasive mountain pine beetle (Dendroctonus ponderosae) and its symbiotic fungus (Grosmannia clavigera). This is the first study to examine the effects of tree fatty acids on any bark beetle species and its symbiotic fungus. In a novel bioassay, we found that plant tissues (hosts and non-host) amended with synthetic fatty acids at concentrations representative of jack pine were compatible with beetle larvae. Likewise, G. clavigera grew in media amended with lipid fractions or synthetic fatty acids at concentrations present in jack pine. In contrast, fatty acids and lipid composition of a non-host were not suitable for the beetle larvae or the fungus. Apparently, concentrations of individual, rather than total, fatty acids determined the suitability of jack pine. Furthermore, sampling of host and non-host tree species across Canada demonstrated that the composition of jack pine fatty acids was similar to the different populations of beetle’s historical hosts. These results demonstrate that fatty acids composition compatible with insect herbivores and their microbial symbionts can be important factor defining host suitability to invasive insects. PMID:27583820

  8. Effects of Dwarf Mistletoe on Stand Structure of Lodgepole Pine Forests 21-28 Years Post-Mountain Pine Beetle Epidemic in Central Oregon

    PubMed Central

    Agne, Michelle C.; Shaw, David C.; Woolley, Travis J.; Queijeiro-Bolaños, Mónica E.

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21–28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to

  9. Effects of dwarf mistletoe on stand structure of lodgepole pine forests 21-28 years post-mountain pine beetle epidemic in central Oregon.

    PubMed

    Agne, Michelle C; Shaw, David C; Woolley, Travis J; Queijeiro-Bolaños, Mónica E

    2014-01-01

    Lodgepole pine (Pinus contorta) forests are widely distributed throughout North America and are subject to mountain pine beetle (Dendroctonus ponderosae) epidemics, which have caused mortality over millions of hectares of mature trees in recent decades. Mountain pine beetle is known to influence stand structure, and has the ability to impact many forest processes. Dwarf mistletoe (Arceuthobium americanum) also influences stand structure and occurs frequently in post-mountain pine beetle epidemic lodgepole pine forests. Few studies have incorporated both disturbances simultaneously although they co-occur frequently on the landscape. The aim of this study is to investigate the stand structure of lodgepole pine forests 21-28 years after a mountain pine beetle epidemic with varying levels of dwarf mistletoe infection in the Deschutes National Forest in central Oregon. We compared stand density, stand basal area, canopy volume, proportion of the stand in dominant/codominant, intermediate, and suppressed cohorts, average height and average diameter of each cohort, across the range of dwarf mistletoe ratings to address differences in stand structure. We found strong evidence of a decrease in canopy volume, suppressed cohort height, and dominant/codominant cohort diameter with increasing stand-level dwarf mistletoe rating. There was strong evidence that as dwarf mistletoe rating increases, proportion of the stand in the dominant/codominant cohort decreases while proportion of the stand in the suppressed cohort increases. Structural differences associated with variable dwarf mistletoe severity create heterogeneity in this forest type and may have a significant influence on stand productivity and the resistance and resilience of these stands to future biotic and abiotic disturbances. Our findings show that it is imperative to incorporate dwarf mistletoe when studying stand productivity and ecosystem recovery processes in lodgepole pine forests because of its potential to

  10. [Blister beetle dermatitis: Dermatitis linearis].

    PubMed

    Dieterle, R; Faulde, M; Erkens, K

    2015-05-01

    Several families of beetles cause toxic reactions on exposed human skin. Cantharidin provokes nearly asymptomatic vesicles and blisters, while pederin leads to itching and burning erythema with vesicles and small pustules, later crusts. Paederi are attracted by fluorescent light especially after rain showers and cause outbreaks in regions with moderate climate. Clinical findings and patient history lead to the diagnosis: dermatitis linearis.

  11. Raising Beetles in a Classroom.

    ERIC Educational Resources Information Center

    Hackett, Erla

    This guide is designed to provide elementary school teachers with a harmless, inexpensive, clean, odorless, and easy-to-care-for insect-rearing project for the classroom. The following topics are included: (1) instructions for the care and feeding of the beetle larvae; (2) student activities for observing larval characteristics and behavior…

  12. The Dung Beetle Dance: An Orientation Behaviour?

    PubMed Central

    Baird, Emily; Byrne, Marcus J.; Smolka, Jochen; Warrant, Eric J.; Dacke, Marie

    2012-01-01

    An interesting feature of dung beetle behaviour is that once they have formed a piece of dung into a ball, they roll it along a straight path away from the dung pile. This straight-line orientation ensures that the beetles depart along the most direct route, guaranteeing that they will not return to the intense competition (from other beetles) that occurs near the dung pile. Before rolling a new ball away from the dung pile, dung beetles perform a characteristic “dance,” in which they climb on top of the ball and rotate about their vertical axis. This dance behaviour can also be observed during the beetles' straight-line departure from the dung pile. The aim of the present study is to investigate the purpose of the dung beetle dance. To do this, we explored the circumstances that elicit dance behaviour in the diurnal ball-rolling dung beetle, Scarabaeus (Kheper) nigroaeneus. Our results reveal that dances are elicited when the beetles lose control of their ball or lose contact with it altogether. We also find that dances can be elicited by both active and passive deviations of course and by changes in visual cues alone. In light of these results, we hypothesise that the dung beetle dance is a visually mediated mechanism that facilitates straight-line orientation in ball-rolling dung beetles by allowing them to 1) establish a roll bearing and 2) return to this chosen bearing after experiencing a disturbance to the roll path. PMID:22279572

  13. The dung beetle dance: an orientation behaviour?

    PubMed

    Baird, Emily; Byrne, Marcus J; Smolka, Jochen; Warrant, Eric J; Dacke, Marie

    2012-01-01

    An interesting feature of dung beetle behaviour is that once they have formed a piece of dung into a ball, they roll it along a straight path away from the dung pile. This straight-line orientation ensures that the beetles depart along the most direct route, guaranteeing that they will not return to the intense competition (from other beetles) that occurs near the dung pile. Before rolling a new ball away from the dung pile, dung beetles perform a characteristic "dance," in which they climb on top of the ball and rotate about their vertical axis. This dance behaviour can also be observed during the beetles' straight-line departure from the dung pile. The aim of the present study is to investigate the purpose of the dung beetle dance. To do this, we explored the circumstances that elicit dance behaviour in the diurnal ball-rolling dung beetle, Scarabaeus (Kheper) nigroaeneus. Our results reveal that dances are elicited when the beetles lose control of their ball or lose contact with it altogether. We also find that dances can be elicited by both active and passive deviations of course and by changes in visual cues alone. In light of these results, we hypothesise that the dung beetle dance is a visually mediated mechanism that facilitates straight-line orientation in ball-rolling dung beetles by allowing them to 1) establish a roll bearing and 2) return to this chosen bearing after experiencing a disturbance to the roll path.

  14. Oedemerid blister beetle dermatosis: a review.

    PubMed

    Nicholls, D S; Christmas, T I; Greig, D E

    1990-05-01

    Blister beetle dermatosis is a distinctive vesiculobullous eruption that occurs after contact with three major groups of beetles (Order: Coleoptera). It is caused by a vesicant chemical contained in the body fluids of the beetles. The smallest and least known family is the Oedemeridae. Although there are few references in the medical literature, blister beetle dermatosis caused by oedemerids may be more common and widespread than currently recognized. The best known family is the Meloidae with numerous species worldwide causing blistering. The vesicant chemical in both Oedemeridae and Meloidae is cantharidin. The third group of blister beetles includes species of the genus Paederus (Family: Staphylinidae). The clinicopathologic picture differs because this genus contains a different vesicant agent, pederin. The clinicopathologic features of oedemerid blister beetle dermatosis are described. The world medical and relevant entomologic literature is reviewed.

  15. Oedemerid blister beetle dermatosis: a review.

    PubMed

    Nicholls, D S; Christmas, T I; Greig, D E

    1990-05-01

    Blister beetle dermatosis is a distinctive vesiculobullous eruption that occurs after contact with three major groups of beetles (Order: Coleoptera). It is caused by a vesicant chemical contained in the body fluids of the beetles. The smallest and least known family is the Oedemeridae. Although there are few references in the medical literature, blister beetle dermatosis caused by oedemerids may be more common and widespread than currently recognized. The best known family is the Meloidae with numerous species worldwide causing blistering. The vesicant chemical in both Oedemeridae and Meloidae is cantharidin. The third group of blister beetles includes species of the genus Paederus (Family: Staphylinidae). The clinicopathologic picture differs because this genus contains a different vesicant agent, pederin. The clinicopathologic features of oedemerid blister beetle dermatosis are described. The world medical and relevant entomologic literature is reviewed. PMID:2189910

  16. Resource release in lodgepole pine across a chronosequence of mountain pine beetle disturbance

    NASA Astrophysics Data System (ADS)

    Brayden, B. H.; Trahan, N. A.; Dynes, E.; Beatty, S. W.; Monson, R. K.

    2011-12-01

    Over the past decade and a half Western North America has experienced a mountain pine beetle (Dendroctonus ponderosae) outbreak on a scale not previously recorded. Millions of hectares of lodgepole pine (Pinus contorta) in high elevation forests have been devastated. Although bark beetles are an important part of the endemic disturbance and regeneration regime in this region, the current unprecedented level of tree mortality will have a significant impact on resources and light availability to surviving trees. We established a decade-long chronosequence of mountain pine beetle disturbance, in a lodgepole stand, composed of three age classes: recent, intermediate, and longest (approximately 2-4, 5-7, 8-10 years respectively) time since initial infestation, as well as a control group. The focus of the study was a healthy tree and it's area of influence (1m radius from the bole), each located in a cluster of the respective chronosequence classes. In the 2011 growing season we have looked at rates of photosynthesis, and water potentials for the healthy trees, as well as soil respiration flux and gravimetric moisture in their areas of influence. We are also in the process of analyzing soil extractable dissolved organic carbon and nitrogen, ammonium, nitrate, and inorganic phosphorus, and plan to take hemispherical photographs and analyze tree-ring stable isotopes to determine if there is any reallocation of soil water use by the trees. Our data shows that photosynthetic rates in the youngest infestation class increase 10 percent over the control group and then falls well bellow the control by the oldest class. The mineral soil gravimetric moisture drastically increases between the control and the recent class and then maintains a consistently higher level through the remaining classes. In contrast, moisture in the organic soil significantly declines between the control and recent class before rebounding to pre-infestation levels in the two older classes. Soil

  17. A Model for Mountain Pine Beetle Outbreaks in an Age-Structured Forest: Predicting Severity and Outbreak-Recovery Cycle Period.

    PubMed

    Duncan, Jacob P; Powell, James A; Gordillo, Luis F; Eason, Joseph

    2015-07-01

    The mountain pine beetle (MPB, Dendroctonus ponderosae), a tree-killing bark beetle, has historically been part of the normal disturbance regime in lodgepole pine (Pinus contorta) forests. In recent years, warm winters and summers have allowed MPB populations to achieve synchronous emergence and successful attacks, resulting in widespread population outbreaks and resultant tree mortality across western North America. We develop an age-structured forest demographic model that incorporates temperature-dependent MPB infestations. Stability of fixed points is analyzed as a function of (thermally controlled) MPB population growth rates and indicates the existence of periodic outbreaks that intensify as growth rates increase. We devise analytical methods to predict outbreak severity and duration as well as outbreak return time. After incorporating a spatial aspect and controlling initial stand demographic variation, the model predicts cycle periods that fall within observed outbreak return time ranges. To assess future MPB impact on forests, we use climate model projected temperatures with our model-based approximation methods to predict potential severity of future outbreaks that reflect the effects of changing climate. PMID:25976694

  18. Variations in foliar monoterpenes across the range of jack pine reveal three widespread chemotypes: implications to host expansion of invasive mountain pine beetle.

    PubMed

    Taft, Spencer; Najar, Ahmed; Godbout, Julie; Bousquet, Jean; Erbilgin, Nadir

    2015-01-01

    The secondary compounds of pines (Pinus) can strongly affect the physiology, ecology and behaviors of the bark beetles (Coleoptera: Curculionidae, Scolytinae) that feed on sub-cortical tissues of hosts. Jack pine (Pinus banksiana) has a wide natural distribution range in North America (Canada and USA) and thus variations in its secondary compounds, particularly monoterpenes, could affect the host expansion of invasive mountain pine beetle (Dendroctonus ponderosae), which has recently expanded its range into the novel jack pine boreal forest. We investigated monoterpene composition of 601 jack pine trees from natural and provenance forest stands representing 63 populations from Alberta to the Atlantic coast. Throughout its range, jack pine exhibited three chemotypes characterized by high proportions of α-pinene, β-pinene, or limonene. The frequency with which the α-pinene and β-pinene chemotypes occurred at individual sites was correlated to climatic variables, such as continentality and mean annual precipitation, as were the individual α-pinene and β-pinene concentrations. However, other monoterpenes were generally not correlated to climatic variables or geographic distribution. Finally, while the enantiomeric ratios of β-pinene and limonene remained constant across jack pine's distribution, (-):(+)-α-pinene exhibited two separate trends, thereby delineating two α-pinene phenotypes, both of which occurred across jack pine's range. These significant variations in jack pine monoterpene composition may have cascading effects on the continued eastward spread and success of D. ponderosae in the Canadian boreal forest. PMID:26042134

  19. A Model for Mountain Pine Beetle Outbreaks in an Age-Structured Forest: Predicting Severity and Outbreak-Recovery Cycle Period.

    PubMed

    Duncan, Jacob P; Powell, James A; Gordillo, Luis F; Eason, Joseph

    2015-07-01

    The mountain pine beetle (MPB, Dendroctonus ponderosae), a tree-killing bark beetle, has historically been part of the normal disturbance regime in lodgepole pine (Pinus contorta) forests. In recent years, warm winters and summers have allowed MPB populations to achieve synchronous emergence and successful attacks, resulting in widespread population outbreaks and resultant tree mortality across western North America. We develop an age-structured forest demographic model that incorporates temperature-dependent MPB infestations. Stability of fixed points is analyzed as a function of (thermally controlled) MPB population growth rates and indicates the existence of periodic outbreaks that intensify as growth rates increase. We devise analytical methods to predict outbreak severity and duration as well as outbreak return time. After incorporating a spatial aspect and controlling initial stand demographic variation, the model predicts cycle periods that fall within observed outbreak return time ranges. To assess future MPB impact on forests, we use climate model projected temperatures with our model-based approximation methods to predict potential severity of future outbreaks that reflect the effects of changing climate.

  20. Variations in foliar monoterpenes across the range of jack pine reveal three widespread chemotypes: implications to host expansion of invasive mountain pine beetle.

    PubMed

    Taft, Spencer; Najar, Ahmed; Godbout, Julie; Bousquet, Jean; Erbilgin, Nadir

    2015-01-01

    The secondary compounds of pines (Pinus) can strongly affect the physiology, ecology and behaviors of the bark beetles (Coleoptera: Curculionidae, Scolytinae) that feed on sub-cortical tissues of hosts. Jack pine (Pinus banksiana) has a wide natural distribution range in North America (Canada and USA) and thus variations in its secondary compounds, particularly monoterpenes, could affect the host expansion of invasive mountain pine beetle (Dendroctonus ponderosae), which has recently expanded its range into the novel jack pine boreal forest. We investigated monoterpene composition of 601 jack pine trees from natural and provenance forest stands representing 63 populations from Alberta to the Atlantic coast. Throughout its range, jack pine exhibited three chemotypes characterized by high proportions of α-pinene, β-pinene, or limonene. The frequency with which the α-pinene and β-pinene chemotypes occurred at individual sites was correlated to climatic variables, such as continentality and mean annual precipitation, as were the individual α-pinene and β-pinene concentrations. However, other monoterpenes were generally not correlated to climatic variables or geographic distribution. Finally, while the enantiomeric ratios of β-pinene and limonene remained constant across jack pine's distribution, (-):(+)-α-pinene exhibited two separate trends, thereby delineating two α-pinene phenotypes, both of which occurred across jack pine's range. These significant variations in jack pine monoterpene composition may have cascading effects on the continued eastward spread and success of D. ponderosae in the Canadian boreal forest.

  1. Stand and landscape level effects of a major outbreak of spruce beetles on forest vegetation in the Copper River Basin, Alaska

    USGS Publications Warehouse

    Allen, J.L.; Wesser, S.; Markon, C.J.; Winterberger, K.C.

    2006-01-01

    From 1989 to 2003, a widespread outbreak of spruce beetles (Dendroctonus rufipennis) in the Copper River Basin, Alaska, infested over 275,000 ha of forests in the region. During 1997 and 1998, we measured forest vegetation structure and composition on one hundred and thirty-six 20-m ?? 20-m plots to assess both the immediate stand and landscape level effects of the spruce beetle infestation. A photo-interpreted vegetation and infestation map was produced using color-infrared aerial photography at a scale of 1:40,000. We used linear regression to quantify the effects of the outbreak on forest structure and composition. White spruce (Picea glauca) canopy cover and basal area of medium-to-large trees [???15 cm diameter-at-breast height (1.3 m, dbh)] were reduced linearly as the number of trees attacked by spruce beetles increased. Black spruce (Picea mariana) and small diameter white spruce (<15 cm dbh) were infrequently attacked and killed by spruce beetles. This selective attack of mature white spruce reduced structural complexity of stands to earlier stages of succession and caused mixed tree species stands to lose their white spruce and become more homogeneous in overstory composition. Using the resulting regressions, we developed a transition matrix to describe changes in vegetation types under varying levels of spruce beetle infestations, and applied the model to the vegetation map. Prior to the outbreak, our study area was composed primarily of stands of mixed white and black spruce (29% of area) and pure white spruce (25%). However, the selective attack on white spruce caused many of these stands to transition to black spruce dominated stands (73% increase in area) or shrublands (26% increase in area). The post-infestation landscape was thereby composed of more even distributions of shrubland and white, black, and mixed spruce communities (17-22% of study area). Changes in the cover and composition of understory vegetation were less evident in this study

  2. Book review: Methods for catching beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beetles are the most speciose animal group and found in virtually all habitats on Earth. Methods for Catching Beetles is a comprehensive general sourcebook about where and how to collect members of this diverse group. The book makes a compelling case in its Introduction about the value of scientif...

  3. Standard methods for small hive beetle research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Small hive beetles, Aethina tumida, are parasites and scavengers of honey bee and other social bee colonies native to sub-Saharan Africa, where they are a minor pest only. In contrast, the beetles can be harmful parasites of European honey bee subspecies. Very rapidly after A. tumida established pop...

  4. Targeting red-headed flea beetle larvae

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red-headed flea beetle (RHFB), Systena frontalis, is an emerging pest of cranberry that requires significant grower investment in monitoring and repeated applications of insecticides to reduce adult populations. The adult beetles are highly mobile and consume a broad range of host plants whereas t...

  5. Blister beetle dermatosis in New Zealand.

    PubMed

    Christmas, T I; Nicholls, D; Holloway, B A; Greig, D

    1987-08-26

    Seventy-four New Zealand Army personnel with a distinctive bullous dermatosis caused by an endemic beetle are described. These are the first reported cases of this condition in New Zealand. The beetle, Thelyphassa lineata (Fabricius) belonging to the family Oedemeridae was shown to be a vesicant species, as skin contact induced blisters in volunteers. This is a previously unrecognised property of this species.

  6. Anemomenotatic orientation in beetles and scorpions

    NASA Technical Reports Server (NTRS)

    Linsenmair, K. E.

    1972-01-01

    Orientation, by beetles and scorpions, according to wind direction and force are analyzed. Major efforts were made to determine: (1) which physical qualities of the air current influence anemomenotaxis, (2) which physiological mechanism is responsible for such orientation, (3) which sense organs do beetles and scorpions use to perceive wind directions, and (4) what the biological significance of anemomenotaxis in the beetle and scorpion is. Experimental results show that the trichobothria in scorpions perceives wind direction; in the beetle it is perceived by sense organs excited by pendicellus-flagellum joint movements. A compensation mechanism is suggested as the basis for anemomenotactic orientation. It was also suggested that the biological significance of anemomenotaxis in scorpions is space orientation; while in beetles it was found to be part of the appetitive behavior used to search for olfactory sign stimuli.

  7. Early Cretaceous angiosperms and beetle evolution

    PubMed Central

    Wang, Bo; Zhang, Haichun; Jarzembowski, Edmund A.

    2013-01-01

    The Coleoptera (beetles) constitute almost one–fourth of all known life-forms on earth. They are also among the most important pollinators of flowering plants, especially basal angiosperms. Beetle fossils are abundant, almost spanning the entire Early Cretaceous, and thus provide important clues to explore the co-evolutionary processes between beetles and angiosperms. We review the fossil record of some Early Cretaceous polyphagan beetles including Tenebrionoidea, Scarabaeoidea, Curculionoidea, and Chrysomeloidea. Both the fossil record and molecular analyses reveal that these four groups had already diversified during or before the Early Cretaceous, clearly before the initial rise of angiosperms to widespread floristic dominance. These four beetle groups are important pollinators of basal angiosperms today, suggesting that their ecological association with angiosperms probably formed as early as in the Early Cretaceous. With the description of additional well-preserved fossils and improvements in phylogenetic analyses, our knowledge of Mesozoic beetle–angiosperm mutualisms will greatly increase during the near future. PMID:24062759

  8. Lunar orientation in a beetle.

    PubMed Central

    Dacke, Marie; Byrne, Marcus J.; Scholtz, Clarke H.; Warrant, Eric J.

    2004-01-01

    Many animals use the sun's polarization pattern to orientate, but the dung beetle Scarabaeus zambesianus is the only animal so far known to orientate using the million times dimmer polarization pattern of the moonlit sky. We demonstrate the relative roles of the moon and the nocturnal polarized-light pattern for orientation. We find that artificially changing the position of the moon, or hiding the moon's disc from the beetle's field of view, generally did not influence its orientation performance. We thus conclude that the moon does not serve as the primary cue for orientation. The effective cue is the polarization pattern formed around the moon, which is more reliable for orientation. Polarization sensitivity ratios in two photoreceptors in the dorsal eye were found to be 7.7 and 12.9, similar to values recorded in diurnal navigators. These results agree with earlier results suggesting that the detection and analysis of polarized skylight is similar in diurnal and nocturnal insects. PMID:15101694

  9. Seed release in serotinous lodgepole pine forests after mountain pine beetle outbreak.

    PubMed

    Teste, François P; Lieffers, Victor J; Landhausser, Simon M

    2011-01-01

    burial; cone opening; Dendroctonus ponderosae; ground-foraging vertebrates; mountain pine beetle; natural regeneration; Pinus contorta var. latifolia; Rocky Mountain lodgepole pine; seed banks; serotiny (canopy seed storage); Tamiasciurus hudsonicus. PMID:21516894

  10. Seed release in serotinous lodgepole pine forests after mountain pine beetle outbreak.

    PubMed

    Teste, François P; Lieffers, Victor J; Landhausser, Simon M

    2011-01-01

    burial; cone opening; Dendroctonus ponderosae; ground-foraging vertebrates; mountain pine beetle; natural regeneration; Pinus contorta var. latifolia; Rocky Mountain lodgepole pine; seed banks; serotiny (canopy seed storage); Tamiasciurus hudsonicus.

  11. An innovative aerial assessment of Greater Yellowstone Ecosystem mountain pine beetle-caused whitebark pine mortality.

    PubMed

    Macfarlane, William W; Logan, Jesse A; Kern, Wilson R

    2013-03-01

    An innovative aerial survey method called the Landscape Assessment System (LAS) was used to assess mountain pine beetle (MPB; Dendroctonus ponderosae)-caused mortality of whitebark pine (Pinus albicaulis) across the species distribution in the Greater Yellowstone Ecosystem (GYE; 894 774 ha). This large-scale implementation of the LAS method consisted of 8673 km of flight lines, along which 4653 geo-tagged, oblique aerial photos were captured at the catchment level (a subset of 12-digit USGS hydrologic units) and geographic information system (GIS) processed. The Mountain Pine Beetle-caused Mortality Rating System, a landscape-scale classification system designed specifically to measure the cumulative effects of recent and older MPB attacks on whitebark pine, was used to classify mortality with a rating from 0 to 6 based on the amount of red (recent attack) and gray (old attack) trees visible. The approach achieved a photo inventory of 79% of the GYE whitebark pine distribution. For the remaining 21%, mortality levels were estimated based on an interpolated surface. Results that combine the photo-inventoried and interpolated mortality indicate that nearly half (46%) of the GYE whitebark pine distribution showed severe mortality (3-4 or 5.3-5.4 rating), 36% showed moderate mortality (2-2.9 rating), 13% showed low mortality (1-1.9 rating), and 5% showed trace levels of mortality (0-0.9). These results reveal that the proliferation of MPB in the subalpine zone of the GYE due to climate warming has led to whitebark pine mortality that is more severe and widespread than indicated from either previous modeling research or USDA Forest Service Aerial Detection surveys. Sixteen of the 22 major mountain ranges of the GYE have experienced widespread moderate-to-severe mortality. The majority of catchments in the other six mountain ranges show low-to-moderate mortality. Refugia from MPB outbreaks, at least for now, also exist and correspond to locations that have colder

  12. Creosote production from beetle infested timber

    SciTech Connect

    Allen, J.F.; Maxwell, T.T.

    1982-01-01

    Wood-tar creosote accumulation in stove pipes and chimneys following burning of beetle-killed southern pine, green pine, seasoned hardwood totalled 6.21, 3.21, 4.27 and 3.73 lb/ton DM respectively. Tests showed that accumulation depends more on air supply to the stove than type or moisture content of wood burned. It is suggested that beetle-killed pine should not be rejected as a fuelwood on the basis of creosote production.

  13. Symbiont diversification in ambrosia beetles: Diversity of fungi associated with exotic scolytine beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In virtually every forest habitat, ambrosia beetles (Coleoptera: Curculionidae: Scolytinae, Platypodinae) plant and maintain symbiotic fungus gardens inside dead or dying wood. Some introduced ambrosia beetles aggressively attack live trees and can damage tree crops, lumber, and native woody plant t...

  14. Volatile emissions from the lesser mealworm beetle Alphitobius diaperinus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The lesser mealworm beetle Alphitobius diaperinus (Panzer) is a serious, cosmopolitan pest in poultry production facilities, consuming grain, carrying disease organisms, and causing structural damage in poultry house walls. Pheromones have been described for many economically important beetle speci...

  15. Do Pine Beetles Fan the Flames in Western Forests?

    NASA Video Gallery

    As mountain pine beetles damage whole regions of Western forests, some worry that the dead trees left behind have created a tinderbox ready to burn. But do pine beetles really increase fire risk? I...

  16. Experimental evidence of bark beetle adaptation to a fungal symbiont.

    PubMed

    Bracewell, Ryan R; Six, Diana L

    2015-11-01

    The importance of symbiotic microbes to insects cannot be overstated; however, we have a poor understanding of the evolutionary processes that shape most insect-microbe interactions. Many bark beetle (Coleoptera: Curculionidae, Scolytinae) species are involved in what have been described as obligate mutualisms with symbiotic fungi. Beetles benefit through supplementing their nutrient-poor diet with fungi and the fungi benefit through gaining transportation to resources. However, only a few beetle-fungal symbioses have been experimentally manipulated to test whether the relationship is obligate. Furthermore, none have tested for adaptation of beetles to their specific symbionts, one of the requirements for coevolution. We experimentally manipulated the western pine beetle-fungus symbiosis to determine whether the beetle is obligately dependent upon fungi and to test for fine-scale adaptation of the beetle to one of its symbiotic fungi, Entomocorticium sp. B. We reared beetles from a single population with either a natal isolate of E. sp. B (isolated from the same population from which the beetles originated), a non-natal isolate (a genetically divergent isolate from a geographically distant beetle population), or with no fungi. We found that fungi were crucial for the successful development of western pine beetles. We also found no significant difference in the effects of the natal and non-natal isolate on beetle fitness parameters. However, brood adult beetles failed to incorporate the non-natal fungus into their fungal transport structure (mycangium) indicating adaption by the beetle to particular genotypes of symbiotic fungi. Our results suggest that beetle-fungus mutualisms and symbiont fidelity may be maintained via an undescribed recognition mechanism of the beetles for particular symbionts that may promote particular associations through time.

  17. New data on flea beetle management in cranberry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Report of two trials conducted this summer for flea beetle management. The first one, conducted in the greenhouse, compares efficacy of native WI nematodes to chemical insecticides for flea beetle control. In this trial, nematodes provided similar control for flea beetles as both insecticides (Belay...

  18. Dosage response mortality of Japanese beetle, masked chafer, and June beetle (Coleoptera: Scarabaeidae) adults when exposed to experimental and commercially available granules containing Metarhizium brunneum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Adult beetles of three different white grub species, Japanese beetle, Popillia japonica, June beetle, Phyllophaga spp., and masked chafer, Cyclocephala spp. were exposed to experimental and commercially available granules containing Metarhizium brunneum (Petch) strain F52, to determine susceptibilit...

  19. Thermal and water relations of desert beetles.

    PubMed

    Cloudsley-Thompson, J L

    2001-11-01

    The physical problems that living organisms have to contend with in hot deserts are primarily extremes of temperature, low humidity, shortage or absence of free water, and the environmental factors that accentuate these--such as strong winds, sand-storms, lack of shade, rocky and impenetrable soils. Climatic factors are particularly important to smaller animals such as arthropods on account of their relatively enormous surface to volume ratios. Nevertheless, beetles (especially Tenebrionidae and, to a lesser extent, Chrysomelidae) are among the most successful animals of the desert, and are often the only ones to be seen abroad during the day. Similar physical problems are experienced by insects in all terrestrial biomes, but they are much enhanced in the desert. Although climatic extremes are often avoided by burrowing habits coupled with circadian and seasonal activity rhythms, as well as reproductive phenology, several species of desert beetle are nevertheless able to withstand thermal extremes that would rapidly cause the death of most other arthropods including insects. The reactions of desert beetles to heat are largely behavioural whilst their responses to water shortage are primarily physiological. The effects of coloration are not discussed. In addition to markedly low rates of transpiration, desert beetles can also withstand a considerable reduction in the water content of their tissues. The study of desert beetles is important because it illustrates many of the solutions evolved by arthropods to the problems engendered, in an extreme form, by life in all terrestrial environments.

  20. Thermal and water relations of desert beetles

    NASA Astrophysics Data System (ADS)

    Cloudsley-Thompson, J.

    2001-11-01

    The physical problems that living organisms have to contend with in hot deserts are primarily extremes of temperature, low humidity, shortage or absence of free water, and the environmental factors that accentuate these - such as strong winds, sand-storms, lack of shade, rocky and impenetrable soils. Climatic factors are particularly important to smaller animals such as arthropods on account of their relatively enormous surface to volume ratios. Nevertheless, beetles (especially Tenebrionidae and, to a lesser extent, Chrysomelidae) are among the most successful animals of the desert, and are often the only ones to be seen abroad during the day. Similar physical problems are experienced by insects in all terrestrial biomes, but they are much enhanced in the desert. Although climatic extremes are often avoided by burrowing habits coupled with circadian and seasonal activity rhythms, as well as reproductive phenology, several species of desert beetle are nevertheless able to withstand thermal extremes that would rapidly cause the death of most other arthropods including insects. The reactions of desert beetles to heat are largely behavioural whilst their responses to water shortage are primarily physiological. The effects of coloration are not discussed. In addition to markedly low rates of transpiration, desert beetles can also withstand a considerable reduction in the water content of their tissues. The study of desert beetles is important because it illustrates many of the solutions evolved by arthropods to the problems engendered, in an extreme form, by life in all terrestrial environments.

  1. Ecosystem CO2/H2O fluxes are explained by hydraulically limited gas exchange during tree mortality from spruce bark beetles

    NASA Astrophysics Data System (ADS)

    Frank, John M.; Massman, William J.; Ewers, Brent E.; Huckaby, Laurie S.; Negrón, José F.

    2014-06-01

    Disturbances are increasing globally due to anthropogenic changes in land use and climate. This study determines whether a disturbance that affects the physiology of individual trees can be used to predict the response of the ecosystem by weighing two competing hypothesis at annual time scales: (a) changes in ecosystem fluxes are proportional to observable patterns of mortality or (b) to explain ecosystem fluxes the physiology of dying trees must also be incorporated. We evaluate these hypotheses by analyzing 6 years of eddy covariance flux data collected throughout the progression of a spruce beetle (Dendroctonus rufipennis) epidemic in a Wyoming Engelmann spruce (Picea engelmannii)-subalpine fir (Abies lasiocarpa) forest and testing for changes in canopy conductance (gc), evapotranspiration (ET), and net ecosystem exchange (NEE) of CO2. We predict from these hypotheses that (a) gc, ET, and NEE all diminish (decrease in absolute magnitude) as trees die or (b) that (1) gc and ET decline as trees are attacked (hydraulic failure from beetle-associated blue-stain fungi) and (2) NEE diminishes both as trees are attacked (restricted gas exchange) and when they die. Ecosystem fluxes declined as the outbreak progressed and the epidemic was best described as two phases: (I) hydraulic failure caused restricted gc, ET (28 ± 4% decline, Bayesian posterior mean ± standard deviation), and gas exchange (NEE diminished 13 ± 6%) and (II) trees died (NEE diminished 51 ± 3% with minimal further change in ET to 36 ± 4%). These results support hypothesis b and suggest that model predictions of ecosystem fluxes following massive disturbances must be modified to account for changes in tree physiological controls and not simply observed mortality.

  2. Variability of snow water equivalent and snow energetics across a large catchment subject to Mountain Pine Beetle infestation and rapid salvage logging

    NASA Astrophysics Data System (ADS)

    Bewley, Dan; Alila, Younes; Varhola, Andrés

    2010-07-01

    SummaryThis study examines the effect on stand and catchment scale snow processes due to widespread forest disturbance by the Mountain Pine Beetle (MPB; Dendroctonus ponderosae) infestation, for the 1570 km 2 Baker Creek catchment in the B.C. interior where all healthy mature lodgepole pine ( Pinus contorta) stands which dominated the catchment up until 2000 have since died or been salvage logged. Measurements in 2008 and 2009 indicate that this net canopy reduction has reduced peak snowpack and melt rate differences between remaining stands (including large clearcuts, younger regenerating stands and dead mature pine stands), relative to a healthy forest canopy with smaller clearcuts. The Distributed Hydrology Soil Vegetation Model (DHSVM) was calibrated and run at 200 m resolution across the catchment, and simulated snowmelt rates and snow-covered area compared relatively well to distributed satellite or ground-based measurements. Snowpack and ablation rates were 10-20% higher during the 2008 and 2009 winters than when running the model for the pre-MPB landscape in 2000 using the same input meteorological data, resulting in almost no difference in the snowcover period. A greater snowpack volume which enters the stream network faster inevitably has implications for streamflows, flood risks and water resources, and these are assessed during the next stage of this research project.

  3. Small hive beetles survive in honeybee prisons by behavioural mimicry

    NASA Astrophysics Data System (ADS)

    Ellis, J. D.; Pirk, C. W. W.; Hepburn, H. R.; Kastberger, G.; Elzen, P. J.

    2002-05-01

    We report the results of a simple experiment to determine whether honeybees feed their small hive beetle nest parasites. Honeybees incarcerate the beetles in cells constructed of plant resins and continually guard them. The longevity of incarcerated beetles greatly exceeds their metabolic reserves. We show that survival of small hive beetles derives from behavioural mimicry by which the beetles induce the bees to feed them trophallactically. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at htpp://dx.doi.org/10.1007/s00114-002-0326-y.

  4. Patterns on the iridescent beetle, Chrysina gloriosa

    NASA Astrophysics Data System (ADS)

    Park, Jung Ok; Sharma, Vivek; Crne, Matija; Srinivasarao, Mohan

    2009-03-01

    The brilliant metallic color of a beetle Chrysina gloriosa has been known to occur due to selective reflectance from a cholesteric structure on the exoskeleton. The surface also appears to have hexagonally packed structures. Crystallographic concepts and Voronoi analysis were used to determine the degree of order in different regions of the beetle. Along the hexagons in the Voronoi diagram, many clustered pentagons and heptagons were observed. Due to the surface curvature, the number of pentagons was found to be higher than the number of heptagons. The cells appear yellow in the center surrounded by a green region with a yellow edge. Confocal microscopy was used to image the underlying structure, which was found to consist of concentric arcs on a surface of a shallow cone. The observed structures resemble the defects on a cholesteric phase with a free surface, and provide an interesting explanation of structural color development in beetles, along with inspiration for the design of chiral photonic structures.

  5. Loss of flight promotes beetle diversification.

    PubMed

    Ikeda, Hiroshi; Nishikawa, Masaaki; Sota, Teiji

    2012-01-31

    The evolution of flight is a key innovation that may enable the extreme diversification of insects. Nonetheless, many species-rich, winged insect groups contain flightless lineages. The loss of flight may promote allopatric differentiation due to limited dispersal power and may result in a high speciation rate in the flightless lineage. Here we show that loss of flight accelerates allopatric speciation using carrion beetles (Coleoptera: Silphidae). We demonstrate that flightless species retain higher genetic differentiation among populations and comprise a higher number of genetically distinct lineages than flight-capable species, and that the speciation rate with the flightless state is twice that with the flight-capable state. Moreover, a meta-analysis of 51 beetle species from 15 families reveals higher genetic differentiation among populations in flightless compared with flight-capable species. In beetles, which represent almost one-fourth of all described species, repeated evolution of flightlessness may have contributed to their steady diversification since the Mesozoic era.

  6. A catalogue of Lithuanian beetles (Insecta, Coleoptera)

    PubMed Central

    Tamutis, Vytautas; Tamutė, Brigita; Ferenca, Romas

    2011-01-01

    Abstract This paper presents the first complete and updated list of all 3597 species of beetles (Insecta: Coleoptera) belonging to 92 familiesfound and published in Lithuania until 2011, with comments also provided on the main systematic and nomenclatural changes since the last monographic treatment in two volumes (Pileckis and Monsevičius 1995, 1997). The introductory section provides a general overview of the main features of the territory of Lithuania, the origins and formation of the beetle fauna and their conservation, the faunistic investigations in Lithuania to date revealing the most important stages of the faunistic research process with reference to the most prominent scientists, an overview of their work, and their contribution to Lithuanian coleopteran faunal research. Species recorded in Lithuania by some authors without reliable evidence and requiring further confirmation with new data are presented in a separate list, consisting of 183 species. For the first time, analysis of errors in works of Lithuanian authors concerning data on coleopteran fauna has been conducted and these errors have been corrected. All available published and Internet sources on beetles found in Lithuania have been considered in the current study. Over 630 literature sources on species composition of beetles, their distribution in Lithuania and neighbouring countries, and taxonomic revisions and changes are reviewed and cited. An alphabetical list of these literature sources is presented. After revision of public beetle collections in Lithuania, the authors propose to remove 43 species from the beetle species list of the country on the grounds, that they have been wrongly identified or published by mistake. For reasons of clarity, 19 previously noted but later excluded species are included in the current checklist with comments. Based on faunal data from neighbouring countries, species expected to occur in Lithuania are matnioned. In total 1390 species are attributed to this

  7. A catalogue of Lithuanian beetles (Insecta, Coleoptera).

    PubMed

    Tamutis, Vytautas; Tamutė, Brigita; Ferenca, Romas

    2011-01-01

    This paper presents the first complete and updated list of all 3597 species of beetles (Insecta: Coleoptera) belonging to 92 familiesfound and published in Lithuania until 2011, with comments also provided on the main systematic and nomenclatural changes since the last monographic treatment in two volumes (Pileckis and Monsevičius 1995, 1997). The introductory section provides a general overview of the main features of the territory of Lithuania, the origins and formation of the beetle fauna and their conservation, the faunistic investigations in Lithuania to date revealing the most important stages of the faunistic research process with reference to the most prominent scientists, an overview of their work, and their contribution to Lithuanian coleopteran faunal research.Species recorded in Lithuania by some authors without reliable evidence and requiring further confirmation with new data are presented in a separate list, consisting of 183 species. For the first time, analysis of errors in works of Lithuanian authors concerning data on coleopteran fauna has been conducted and these errors have been corrected. All available published and Internet sources on beetles found in Lithuania have been considered in the current study. Over 630 literature sources on species composition of beetles, their distribution in Lithuania and neighbouring countries, and taxonomic revisions and changes are reviewed and cited. An alphabetical list of these literature sources is presented. After revision of public beetle collections in Lithuania, the authors propose to remove 43 species from the beetle species list of the country on the grounds, that they have been wrongly identified or published by mistake. For reasons of clarity, 19 previously noted but later excluded species are included in the current checklist with comments. Based on faunal data from neighbouring countries, species expected to occur in Lithuania are matnioned. In total 1390 species are attributed to this category

  8. Beetle and plant density as cues initiating dispersal in two species of adult predaceous diving beetles.

    PubMed

    Yee, Donald A; Taylor, Stacy; Vamosi, Steven M

    2009-05-01

    Dispersal can influence population dynamics, species distributions, and community assembly, but few studies have attempted to determine the factors that affect dispersal of insects in natural populations. Consequently, little is known about how proximate factors affect the dispersal behavior of individuals or populations, or how an organism's behavior may change in light of such factors. Adult predaceous diving beetles are active dispersers and are important predators in isolated aquatic habitats. We conducted interrelated studies to determine how several factors affected dispersal in two common pond-inhabiting species in southern Alberta, Canada: Graphoderus occidentalis and Rhantus sericans. Specifically, we (1) experimentally tested the effect of plant and beetle densities on dispersal probabilities in ponds; (2) surveyed ponds and determined the relationships among beetle densities and plant densities and water depth; and (3) conducted laboratory trials to determine how beetle behavior changed in response to variation in plant densities, conspecific densities, food, and water depth. Our field experiment determined that both species exhibited density dependence, with higher beetle densities leading to higher dispersal probabilities. Low plant density also appeared to increase beetle dispersal. Consistent with our experimental results, densities of R. sericans in ponds were significantly related to plant density and varied also with water depth; G. occidentalis densities did not vary with either factor. In the laboratory, behavior varied with plant density only for R. sericans, which swam at low density but were sedentary at high density. Both species responded to depth, with high beetle densities eliciting beetles to spend more time in deeper water. The presence of food caused opposite responses for G. occidentalis between experiments. Behavioral changes in response to patch-level heterogeneity likely influence dispersal in natural populations and are expected

  9. Beetle and plant density as cues initiating dispersal in two species of adult predaceous diving beetles.

    PubMed

    Yee, Donald A; Taylor, Stacy; Vamosi, Steven M

    2009-05-01

    Dispersal can influence population dynamics, species distributions, and community assembly, but few studies have attempted to determine the factors that affect dispersal of insects in natural populations. Consequently, little is known about how proximate factors affect the dispersal behavior of individuals or populations, or how an organism's behavior may change in light of such factors. Adult predaceous diving beetles are active dispersers and are important predators in isolated aquatic habitats. We conducted interrelated studies to determine how several factors affected dispersal in two common pond-inhabiting species in southern Alberta, Canada: Graphoderus occidentalis and Rhantus sericans. Specifically, we (1) experimentally tested the effect of plant and beetle densities on dispersal probabilities in ponds; (2) surveyed ponds and determined the relationships among beetle densities and plant densities and water depth; and (3) conducted laboratory trials to determine how beetle behavior changed in response to variation in plant densities, conspecific densities, food, and water depth. Our field experiment determined that both species exhibited density dependence, with higher beetle densities leading to higher dispersal probabilities. Low plant density also appeared to increase beetle dispersal. Consistent with our experimental results, densities of R. sericans in ponds were significantly related to plant density and varied also with water depth; G. occidentalis densities did not vary with either factor. In the laboratory, behavior varied with plant density only for R. sericans, which swam at low density but were sedentary at high density. Both species responded to depth, with high beetle densities eliciting beetles to spend more time in deeper water. The presence of food caused opposite responses for G. occidentalis between experiments. Behavioral changes in response to patch-level heterogeneity likely influence dispersal in natural populations and are expected

  10. Impact of the Mountain Pine Beetle on the Forest Carbon Cycle in British Columbia from 1999 TO 2008 (Invited)

    NASA Astrophysics Data System (ADS)

    Chen, J. M.; Czurylowicz, P.; Mo, G.; Black, T. A.

    2013-12-01

    The unprecedented mountain pine beetle (Dendroctonus ponderosae) (MPB) outbreak in British Columbia starting in 1998 affected about 50% of the lodgepole pine (Pinus contorta var. latifolia) forests occupying about 50% of the land area of the province. The impact of this outbreak on the C cycle is assessed in this study. Annual leaf area index (LAI) maps of the affected area from 1999 to 2008 were produced using SPOT VEGETATION data, and net ecosystem production (NEP) was modeled using inputs of LAI, land cover, soil texture and daily meteorological data with the Boreal Ecosystem Productivity Simulator (BEPS). Both LAI and NEP were validated using field measurements. LAI was found to decrease on average by 20% compared to pre-outbreak conditions, while NEP decreased on average by 90%. Annual NEP values ranged from 2.4 to -8.0 Tg C between 1999 and 2008, with the ecosystem changing from a carbon sink to a carbon source in 2000. The annual average NEP was -2.9 Tg C over the 10 years, resulting in a total loss of carbon of 29 Tg C to the atmosphere. The inter-annual variability of both LAI and NEP was characterized by substantial initial decreases followed by steady increases from 2006 to 2008 with NEP returning to near carbon neutrality in 2008 (-1.8 Pg C/y). The impact of this MPB outbreak appears to be less dramatic than previously anticipated. The apparent fast recovery of LAI and NEP after MPB attacks is examined under the framework of ecosystem resilience which was manifested in the form of secondary overstory and understory growth and increased production of non-attacked host trees.

  11. Effects of water potential and solute on the growth and interactions of two fungal symbionts of the mountain pine beetle.

    PubMed

    Bleiker, K P; Six, D L

    2009-01-01

    We investigated the effect of water potential (WP) on the growth of, and interaction between, two ophiostomatoid fungi, Grosmannia clavigera and Ophiostoma montium, associated with the mountain pine beetle (Dendroctonus ponderosae). The WP of malt extract agar was amended by adding potassium chloride (KCl) or sucrose. Growth of both fungi decreased with WP on KCl-amended media. Growth of G. clavigera also decreased with WP on sucrose-amended media, although growth was stimulated on these media compared to unamended treatments. Growth of O. montium remained relatively constant on sucrose-amended media, confounding the effect of WP on this species. Both fungi were able to colonize media occupied by the other species, but at a slower rate than on unoccupied media, indicating competition. In most treatments, G. clavigera grew faster than O. montium and colonized a greater area when the two fungi were inoculated concurrently but distant to one another on a Petri dish. However, when each fungus was inoculated adjacent to a 10-d-old well-established colony of the other species, O. montium colonized occupied media more effectively than G. clavigera considering the growth rate of each species alone. Thus, G. clavigera dominated primary (uncolonized) resources on most media, whereas O. montium was more effective in colonizing secondary (occupied) resources. The differential response of the two fungi to sucrose indicates that they may use different carbon sources, or use different carbon sources at different rates, in the tree. Fine-scale resource partitioning, differences in primary and secondary resource capture abilities, and the non-equilibrium dynamics in an attacked tree over time, could all act to promote the co-existence of two unit-restricted dispersers on a discontinuous resource.

  12. Gene discovery for enzymes involved in limonene modification or utilization by the mountain pine beetle-associated pathogen Grosmannia clavigera.

    PubMed

    Wang, Ye; Lim, Lynette; Madilao, Lina; Lah, Ljerka; Bohlmann, Joerg; Breuil, Colette

    2014-08-01

    To successfully colonize and eventually kill pine trees, Grosmannia clavigera (Gs cryptic species), the main fungal pathogen associated with the mountain pine beetle (Dendroctonus ponderosae), has developed multiple mechanisms to overcome host tree chemical defenses, of which terpenoids are a major component. In addition to a monoterpene efflux system mediated by a recently discovered ABC transporter, Gs has genes that are highly induced by monoterpenes and that encode enzymes that modify or utilize monoterpenes [especially (+)-limonene]. We showed that pine-inhabiting Ophiostomale fungi are tolerant to monoterpenes, but only a few, including Gs, are known to utilize monoterpenes as a carbon source. Gas chromatography-mass spectrometry (GC-MS) revealed that Gs can modify (+)-limonene through various oxygenation pathways, producing carvone, p-mentha-2,8-dienol, perillyl alcohol, and isopiperitenol. It can also degrade (+)-limonene through the C-1-oxygenated pathway, producing limonene-1,2-diol as the most abundant intermediate. Transcriptome sequencing (RNA-seq) data indicated that Gs may utilize limonene 1,2-diol through beta-oxidation and then valine and tricarboxylic acid (TCA) metabolic pathways. The data also suggested that at least two gene clusters, located in genome contigs 108 and 161, were highly induced by monoterpenes and may be involved in monoterpene degradation processes. Further, gene knockouts indicated that limonene degradation required two distinct Baeyer-Villiger monooxygenases (BVMOs), an epoxide hydrolase and an enoyl coenzyme A (enoyl-CoA) hydratase. Our work provides information on enzyme-mediated limonene utilization or modification and a more comprehensive understanding of the interaction between an economically important fungal pathogen and its host's defense chemicals.

  13. Gene Discovery for Enzymes Involved in Limonene Modification or Utilization by the Mountain Pine Beetle-Associated Pathogen Grosmannia clavigera

    PubMed Central

    Wang, Ye; Lim, Lynette; Madilao, Lina; Lah, Ljerka; Bohlmann, Joerg

    2014-01-01

    To successfully colonize and eventually kill pine trees, Grosmannia clavigera (Gs cryptic species), the main fungal pathogen associated with the mountain pine beetle (Dendroctonus ponderosae), has developed multiple mechanisms to overcome host tree chemical defenses, of which terpenoids are a major component. In addition to a monoterpene efflux system mediated by a recently discovered ABC transporter, Gs has genes that are highly induced by monoterpenes and that encode enzymes that modify or utilize monoterpenes [especially (+)-limonene]. We showed that pine-inhabiting Ophiostomale fungi are tolerant to monoterpenes, but only a few, including Gs, are known to utilize monoterpenes as a carbon source. Gas chromatography-mass spectrometry (GC-MS) revealed that Gs can modify (+)-limonene through various oxygenation pathways, producing carvone, p-mentha-2,8-dienol, perillyl alcohol, and isopiperitenol. It can also degrade (+)-limonene through the C-1-oxygenated pathway, producing limonene-1,2-diol as the most abundant intermediate. Transcriptome sequencing (RNA-seq) data indicated that Gs may utilize limonene 1,2-diol through beta-oxidation and then valine and tricarboxylic acid (TCA) metabolic pathways. The data also suggested that at least two gene clusters, located in genome contigs 108 and 161, were highly induced by monoterpenes and may be involved in monoterpene degradation processes. Further, gene knockouts indicated that limonene degradation required two distinct Baeyer-Villiger monooxygenases (BVMOs), an epoxide hydrolase and an enoyl coenzyme A (enoyl-CoA) hydratase. Our work provides information on enzyme-mediated limonene utilization or modification and a more comprehensive understanding of the interaction between an economically important fungal pathogen and its host's defense chemicals. PMID:24837377

  14. Chirality determines pheromone activity for flour beetles

    NASA Astrophysics Data System (ADS)

    Levinson, H. Z.; Mori, K.

    1983-04-01

    Olfactory perception and orientation behaviour of female and male flour beetles ( Tribolium castaneum, T. confusum) to single stereoisomers of their aggregation pheromone revealed maximal receptor potentials and optimal attraction in response to 4R,8R-(-)-dimethyldecanal, whereas its optical antipode 4S,8S-(+)-dimethyldecanal was found to be inactive in this respect. Female flour beetles of both species were ≈ 103 times less attracted to 4R,8S-(+)- and 4S,8R-(-)-dimethyldecanal than to 4R,8R-(-)-dimethyldecanal, while male flour beetles failed to respond to the R,S-(+)- and S,R-(-)-stereoisomers. Pheromone extracts of prothoracic femora from unmated male flour beetles elicited higher receptor potentials in the antennae of females than in those of males. The results suggest that the aggregation pheromone emitted by male T. castaneum as well as male T. confusum has the stereochemical structure of 4R,8R-(-)-dimethyl-decanal, which acts as sex attractant for the females and as aggregant for the males of both species.

  15. Systematics of Fusaria associated with Ambrosia beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here, I summarize research efforts directed at characterizing ambrosia beetle-associated fusaria, including the species responsible for avocado wilt in Israel (Mendel et al., Phytoparasitica 2012) and branch dieback in California (Eskalen et al., Pl. Dis. 2012). Our multilocus molecular phylogenetic...

  16. Tiger beetle's pursuit of prey depends on distance

    NASA Astrophysics Data System (ADS)

    Noest, Robert; Wang, Jane

    2015-03-01

    Tiger beetles are fast predators capable of chasing prey under closed-loop visual guidance. We investigated their control system using high-speed digital recordings of beetles chasing a moving prey dummy in a laboratory arena. Analysis reveals that the beetle uses a proportional control law in which the angular position of the prey relative to the beetle's body axis drives the beetle's angular velocity with a delay of about 28 ms. The system gain is shown to depend on the beetle-prey distance in a pattern indicating three hunting phases over the observed distance domain. We show that to explain this behavior the tiger beetle must be capable of visually determining the distance to its target and using that to adapt the gain in its proportional control law. We will end with a discussion on the possible methods for distance detection by the tiger beetle and focus on two of them. Motion parallax, using the natural head sway induced by the walking gait of the tiger beetle, is shown to have insufficient distance range. However elevation in the field of vision, using the angle with respect to the horizon at which a target is observed, has a much larger distance range and is a prime candidate for the mechanism of visual distance detection in the tiger beetle.

  17. The fossil record and macroevolutionary history of the beetles.

    PubMed

    Smith, Dena M; Marcot, Jonathan D

    2015-04-22

    Coleoptera (beetles) is the most species-rich metazoan order, with approximately 380 000 species. To understand how they came to be such a diverse group, we compile a database of global fossil beetle occurrences to study their macroevolutionary history. Our database includes 5553 beetle occurrences from 221 fossil localities. Amber and lacustrine deposits preserve most of the beetle diversity and abundance. All four extant suborders are found in the fossil record, with 69% of all beetle families and 63% of extant beetle families preserved. Considerable focus has been placed on beetle diversification overall, however, for much of their evolutionary history it is the clade Polyphaga that is most responsible for their taxonomic richness. Polyphaga had an increase in diversification rate in the Early Cretaceous, but instead of being due to the radiation of the angiosperms, this was probably due to the first occurrences of beetle-bearing amber deposits in the record. Perhaps, most significant is that polyphagan beetles had a family-level extinction rate of zero for most of their evolutionary history, including across the Cretaceous-Palaeogene boundary. Therefore, focusing on the factors that have inhibited beetle extinction, as opposed to solely studying mechanisms that may promote speciation, should be examined as important determinants of their great diversity today.

  18. Discordant phylogenies suggest repeated host shifts in the Fusarium–Euwallacea ambrosia beetle mutualism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mutualism between xyleborine beetles in the genus Euwallacea (Coleoptera: Curculionidae: Scolytinae) and members of the Ambrosia Fusarium Clade (AFC) represents one of 11 known independent evolutionary origins of fungiculture by ambrosia beetles. Female Euwallacea beetles transport fusarial symb...

  19. Floral associations of cyclocephaline scarab beetles.

    PubMed

    Moore, Matthew Robert; Jameson, Mary Liz

    2013-01-01

    The scarab beetle tribe Cyclocephalini (Coleoptera: Scarabaeidae: Dynastinae) is the second largest tribe of rhinoceros beetles, with nearly 500 described species. This diverse group is most closely associated with early diverging angiosperm groups (the family Nymphaeaceae, magnoliid clade, and monocots), where they feed, mate, and receive the benefit of thermal rewards from the host plant. Cyclocephaline floral association data have never been synthesized, and a comprehensive review of this ecological interaction was necessary to promote research by updating nomenclature, identifying inconsistencies in the data, and reporting previously unpublished data. Based on the most specific data, at least 97 cyclocephaline beetle species have been reported from the flowers of 58 plant genera representing 17 families and 15 orders. Thirteen new cyclocephaline floral associations are reported herein. Six cyclocephaline and 25 plant synonyms were reported in the literature and on beetle voucher specimen labels, and these were updated to reflect current nomenclature. The valid names of three unavailable plant host names were identified. We review the cyclocephaline floral associations with respect to inferred relationships of angiosperm orders. Ten genera of cyclocephaline beetles have been recorded from flowers of early diverging angiosperm groups. In contrast, only one genus, Cyclocephala, has been recorded from dicot flowers. Cyclocephaline visitation of dicot flowers is limited to the New World, and it is unknown whether this is evolutionary meaningful or the result of sampling bias and incomplete data. The most important areas for future research include: (1) elucidating the factors that attract cyclocephalines to flowers including floral scent chemistry and thermogenesis, (2) determining whether cyclocephaline dicot visitation is truly limited to the New World, and (3) inferring evolutionary relationships within the Cyclocephalini to rigorously test vicarance hypotheses

  20. Floral associations of cyclocephaline scarab beetles.

    PubMed

    Moore, Matthew Robert; Jameson, Mary Liz

    2013-01-01

    The scarab beetle tribe Cyclocephalini (Coleoptera: Scarabaeidae: Dynastinae) is the second largest tribe of rhinoceros beetles, with nearly 500 described species. This diverse group is most closely associated with early diverging angiosperm groups (the family Nymphaeaceae, magnoliid clade, and monocots), where they feed, mate, and receive the benefit of thermal rewards from the host plant. Cyclocephaline floral association data have never been synthesized, and a comprehensive review of this ecological interaction was necessary to promote research by updating nomenclature, identifying inconsistencies in the data, and reporting previously unpublished data. Based on the most specific data, at least 97 cyclocephaline beetle species have been reported from the flowers of 58 plant genera representing 17 families and 15 orders. Thirteen new cyclocephaline floral associations are reported herein. Six cyclocephaline and 25 plant synonyms were reported in the literature and on beetle voucher specimen labels, and these were updated to reflect current nomenclature. The valid names of three unavailable plant host names were identified. We review the cyclocephaline floral associations with respect to inferred relationships of angiosperm orders. Ten genera of cyclocephaline beetles have been recorded from flowers of early diverging angiosperm groups. In contrast, only one genus, Cyclocephala, has been recorded from dicot flowers. Cyclocephaline visitation of dicot flowers is limited to the New World, and it is unknown whether this is evolutionary meaningful or the result of sampling bias and incomplete data. The most important areas for future research include: (1) elucidating the factors that attract cyclocephalines to flowers including floral scent chemistry and thermogenesis, (2) determining whether cyclocephaline dicot visitation is truly limited to the New World, and (3) inferring evolutionary relationships within the Cyclocephalini to rigorously test vicarance hypotheses

  1. Floral Associations of Cyclocephaline Scarab Beetles

    PubMed Central

    Moore, Matthew Robert; Jameson, Mary Liz

    2013-01-01

    The scarab beetle tribe Cyclocephalini (Coleoptera: Scarabaeidae: Dynastinae) is the second largest tribe of rhinoceros beetles, with nearly 500 described species. This diverse group is most closely associated with early diverging angiosperm groups (the family Nymphaeaceae, magnoliid clade, and monocots), where they feed, mate, and receive the benefit of thermal rewards from the host plant. Cyclocephaline floral association data have never been synthesized, and a comprehensive review of this ecological interaction was necessary to promote research by updating nomenclature, identifying inconsistencies in the data, and reporting previously unpublished data. Based on the most specific data, at least 97 cyclocephaline beetle species have been reported from the flowers of 58 plant genera representing 17 families and 15 orders. Thirteen new cyclocephaline floral associations are reported herein. Six cyclocephaline and 25 plant synonyms were reported in the literature and on beetle voucher specimen labels, and these were updated to reflect current nomenclature. The valid names of three unavailable plant host names were identified. We review the cyclocephaline floral associations with respect to inferred relationships of angiosperm orders. Ten genera of cyclocephaline beetles have been recorded from flowers of early diverging angiosperm groups. In contrast, only one genus, Cyclocephala, has been recorded from dicot flowers. Cyclocephaline visitation of dicot flowers is limited to the New World, and it is unknown whether this is evolutionary meaningful or the result of sampling bias and incomplete data. The most important areas for future research include: 1) elucidating the factors that attract cyclocephalines to flowers including floral scent chemistry and thermogenesis, 2) determining whether cyclocephaline dicot visitation is truly limited to the New World, and 3) inferring evolutionary relationships within the Cyclocephalini to rigorously test vicarance hypotheses

  2. Wildfires, mountain pine beetle and large-scale climate in Northern North America.

    NASA Astrophysics Data System (ADS)

    Macias Fauria, M.; Johnson, E. A.

    2009-05-01

    Research on the interactions between biosphere and atmosphere and ocean/atmosphere dynamics, concretely on the coupling between ecological processes and large-scale climate, is presented in two studies in Northern North America: the occurrence of large lightning wildfires and the forest area affected by mountain pine beetle (Dendroctonus ponderosae, MPB). In both cases, large-scale climatic patterns such as the Pacific Decadal Oscillation (PDO) and the Arctic Oscillation (AO) operate as low and low and high frequency frameworks, respectively, that control the occurrence, duration and spatial correlation over large areas of key local weather variables which affect specific ecological processes. Warm PDO phases tend to produce persistent (more than 10 days long) positive mid-troposphere anomalies (blocking highs) over western Canada and Alaska. Likewise, positive (negative) AO configurations increase the frequency of blocking highs at mid (high) latitudes of the Northern Hemisphere. Under these conditions, lack of precipitation and prevailing warm air meridional flow rapidly dry fuel over large areas and increase fire hazard. The spatiotemporal patterns of occurrence of large lightning wildfire in Canada and Alaska for 1959-1999 were largely explained by the action and possible interaction of AO and PDO, the AO being more influential over Eastern Canada, the PDO over Western Canada and Alaska. Changes in the dynamics of the PDO are linked to the occurrence of cold winter temperatures in British Columbia (BC), Western Canada. Reduced frequency of cold events during warm PDO winters is consistent with a northward-displaced polar jet stream inhibiting the outflow of cold Arctic air over BC. Likewise, the AO influences the occurrence of winter cold spells in the area. PDO, and to a lesser degree AO, were strongly related to MPB synchrony in BC during 1959-2002, operating through the control of the frequency of extreme cold winter temperatures that affect MPB larvae

  3. A structured threshold model for mountain pine beetle outbreak.

    PubMed

    Lewis, Mark A; Nelson, William; Xu, Cailin

    2010-04-01

    A vigor-structured model for mountain pine beetle outbreak dynamics within a forest stand is proposed and analyzed. This model explicitly tracks the changing vigor structure in the stand. All model parameters, other than beetle vigor preference, were determined by fitting model components to empirical data. An abrupt threshold for tree mortality to beetle densities allows for model simplification. Based on initial beetle density, model outcomes vary from decimation of the entire stand in a single year, to inability of the beetles to infect any trees. An intermediate outcome involves an initial infestation which subsequently dies out before the entire stand is killed. A model extension is proposed for dynamics of beetle aggregation. This involves a stochastic formulation.

  4. The bacterial community of entomophilic nematodes and host beetles.

    PubMed

    Koneru, Sneha L; Salinas, Heilly; Flores, Gilberto E; Hong, Ray L

    2016-05-01

    Insects form the most species-rich lineage of Eukaryotes and each is a potential host for organisms from multiple phyla, including fungi, protozoa, mites, bacteria and nematodes. In particular, beetles are known to be associated with distinct bacterial communities and entomophilic nematodes. While entomopathogenic nematodes require symbiotic bacteria to kill and reproduce inside their insect hosts, the microbial ecology that facilitates other types of nematode-insect associations is largely unknown. To illuminate detailed patterns of the tritrophic beetle-nematode-bacteria relationship, we surveyed the nematode infestation profiles of scarab beetles in the greater Los Angeles area over a five-year period and found distinct nematode infestation patterns for certain beetle hosts. Over a single season, we characterized the bacterial communities of beetles and their associated nematodes using high-throughput sequencing of the 16S rRNA gene. We found significant differences in bacterial community composition among the five prevalent beetle host species, independent of geographical origin. Anaerobes Synergistaceae and sulphate-reducing Desulfovibrionaceae were most abundant in Amblonoxia beetles, while Enterobacteriaceae and Lachnospiraceae were common in Cyclocephala beetles. Unlike entomopathogenic nematodes that carry bacterial symbionts, insect-associated nematodes do not alter the beetles' native bacterial communities, nor do their microbiomes differ according to nematode or beetle host species. The conservation of Diplogastrid nematodes associations with Melolonthinae beetles and sulphate-reducing bacteria suggests a possible link between beetle-bacterial communities and their associated nematodes. Our results establish a starting point towards understanding the dynamic interactions between soil macroinvertebrates and their microbiota in a highly accessible urban environment.

  5. Endozoochory by beetles: a novel seed dispersal mechanism

    PubMed Central

    de Vega, Clara; Arista, Montserrat; Ortiz, Pedro L.; Herrera, Carlos M.; Talavera, Salvador

    2011-01-01

    Background and Aims Due in part to biophysical sized-related constraints, insects unlike vertebrates are seldom expected to act as primary seed dispersers via ingestion of fruits and seeds (endozoochory). The Mediterranean parasitic plant Cytinus hypocistis, however, possesses some characteristics that may facilitate endozoochory by beetles. By combining a long-term field study with experimental manipulation, we tested whether C. hypocistis seeds are endozoochorously dispersed by beetles. Methods Field studies were carried out over 4 years on six populations in southern Spain. We recorded the rate of natural fruit consumption by beetles, the extent of beetle movement, beetle behaviour and the relative importance of C. hypocistis fruits in beetle diet. Key Results The tenebrionid beetle Pimelia costata was an important disperser of C. hypocistis seeds, consuming up to 17·5 % of fruits per population. Forty-six per cent of beetles captured in the field consumed C. hypocistis fruits, with up to 31 seeds found in individual beetle frass. An assessment of seeds following passage through the gut of beetles indicated that seeds remained intact and viable and that the proportion of viable seeds from beetle frass was not significantly different from that of seeds collected directly from fruits. Conclusions A novel plant–animal interaction is revealed; endozoochory by beetles may facilitate the dispersal of viable seeds after passage through the gut away from the parent plant to potentially favourable underground sites offering a high probability of germination and establishment success. Such an ecological role has until now been attributed only to vertebrates. Future studies should consider more widely the putative role of fruit and seed ingestion by invertebrates as a dispersal mechanism, particularly for those plant species that possess small seeds. PMID:21303784

  6. The bacterial community of entomophilic nematodes and host beetles.

    PubMed

    Koneru, Sneha L; Salinas, Heilly; Flores, Gilberto E; Hong, Ray L

    2016-05-01

    Insects form the most species-rich lineage of Eukaryotes and each is a potential host for organisms from multiple phyla, including fungi, protozoa, mites, bacteria and nematodes. In particular, beetles are known to be associated with distinct bacterial communities and entomophilic nematodes. While entomopathogenic nematodes require symbiotic bacteria to kill and reproduce inside their insect hosts, the microbial ecology that facilitates other types of nematode-insect associations is largely unknown. To illuminate detailed patterns of the tritrophic beetle-nematode-bacteria relationship, we surveyed the nematode infestation profiles of scarab beetles in the greater Los Angeles area over a five-year period and found distinct nematode infestation patterns for certain beetle hosts. Over a single season, we characterized the bacterial communities of beetles and their associated nematodes using high-throughput sequencing of the 16S rRNA gene. We found significant differences in bacterial community composition among the five prevalent beetle host species, independent of geographical origin. Anaerobes Synergistaceae and sulphate-reducing Desulfovibrionaceae were most abundant in Amblonoxia beetles, while Enterobacteriaceae and Lachnospiraceae were common in Cyclocephala beetles. Unlike entomopathogenic nematodes that carry bacterial symbionts, insect-associated nematodes do not alter the beetles' native bacterial communities, nor do their microbiomes differ according to nematode or beetle host species. The conservation of Diplogastrid nematodes associations with Melolonthinae beetles and sulphate-reducing bacteria suggests a possible link between beetle-bacterial communities and their associated nematodes. Our results establish a starting point towards understanding the dynamic interactions between soil macroinvertebrates and their microbiota in a highly accessible urban environment. PMID:26992100

  7. iBeetle-Base: a database for RNAi phenotypes in the red flour beetle Tribolium castaneum.

    PubMed

    Dönitz, Jürgen; Schmitt-Engel, Christian; Grossmann, Daniela; Gerischer, Lizzy; Tech, Maike; Schoppmeier, Michael; Klingler, Martin; Bucher, Gregor

    2015-01-01

    The iBeetle-Base (http://ibeetle-base.uni-goettingen.de) makes available annotations of RNAi phenotypes, which were gathered in a large scale RNAi screen in the red flour beetle Tribolium castaneum (iBeetle screen). In addition, it provides access to sequence information and links for all Tribolium castaneum genes. The iBeetle-Base contains the annotations of phenotypes of several thousands of genes knocked down during embryonic and metamorphic epidermis and muscle development in addition to phenotypes linked to oogenesis and stink gland biology. The phenotypes are described according to the EQM (entity, quality, modifier) system using controlled vocabularies and the Tribolium morphological ontology (TrOn). Furthermore, images linked to the respective annotations are provided. The data are searchable either for specific phenotypes using a complex 'search for morphological defects' or a 'quick search' for gene names and IDs. The red flour beetle Tribolium castaneum has become an important model system for insect functional genetics and is a representative of the most species rich taxon, the Coleoptera, which comprise several devastating pests. It is used for studying insect typical development, the evolution of development and for research on metabolism and pest control. Besides Drosophila, Tribolium is the first insect model organism where large scale unbiased screens have been performed.

  8. Colorado potato beetle toxins revisited: evidence the beetle does not sequester host plant glycoalkaloids.

    PubMed

    Armer, Christine A

    2004-04-01

    The Colorado potato beetle feeds only on glycoalkaloid-laden solanaceous plants, appears to be toxic to predators, and has aposematic coloration, suggesting the beetle may sequester alkaloids from its host plants. This study tested 4th instars and adults, as well as isolated hemolymph and excrement, to determine if the beetles sequester, metabolize, or excrete alkaloids ingested from their host plants. HPLC analysis showed: that neither the larvae nor the adults sequestered either solanine or chaconine from potato foliage; that any alkaloids in the beetles were at concentrations well below 1 ppm; and that alkaloids were found in the excrement of larvae at approximately the same concentrations as in foliage. Analysis of alkaloids in the remains of fed-upon leaflet halves plus excreta during 24 hr feeding by 4th instars, as compared to alkaloids in the uneaten halves of the leaflets, showed that equal amounts of alkaloids were excreted as were ingested. The aposematic coloration probably warns of a previously-identified toxic dipeptide instead of a plant-derived alkaloid, as the Colorado potato beetle appears to excrete, rather than sequester or metabolize, the alkaloids from its host plants.

  9. Atlas of Iberian water beetles (ESACIB database).

    PubMed

    Sánchez-Fernández, David; Millán, Andrés; Abellán, Pedro; Picazo, Félix; Carbonell, José A; Ribera, Ignacio

    2015-01-01

    The ESACIB ('EScarabajos ACuáticos IBéricos') database is provided, including all available distributional data of Iberian and Balearic water beetles from the literature up to 2013, as well as from museum and private collections, PhD theses, and other unpublished sources. The database contains 62,015 records with associated geographic data (10×10 km UTM squares) for 488 species and subspecies of water beetles, 120 of them endemic to the Iberian Peninsula and eight to the Balearic Islands. This database was used for the elaboration of the "Atlas de los Coleópteros Acuáticos de España Peninsular". In this dataset data of 15 additional species has been added: 11 that occur in the Balearic Islands or mainland Portugal but not in peninsular Spain and an other four with mainly terrestrial habits within the genus Helophorus (for taxonomic coherence). The complete dataset is provided in Darwin Core Archive format.

  10. Lehr's fields of campaniform sensilla in beetles (Coleoptera): functional morphology. III. Modification of elytral mobility or shape in flying beetles.

    PubMed

    Frantsevich, Leonid; Gorb, Stanislav; Radchenko, Vladimir; Gladun, Dmytro

    2015-03-01

    Some flying beetles have peculiar functional properties of their elytra, if compared with the vast majority of beetles. A "typical" beetle covers its pterothorax and the abdomen from above with closed elytra and links closed elytra together along the sutural edges. In the open state during flight, the sutural edges diverge much more than by 90°. Several beetles of unrelated taxa spread wings through lateral incisions on the elytra and turn the elytron during opening about 10-12° (Cetoniini, Scarabaeus, Gymnopleurus) or elevate their elytra without partition (Sisyphus, Tragocerus). The number of campaniform sensilla in their elytral sensory field is diminished in comparison with beetles of closely related taxa lacking that incision. Elytra are very short in rove beetles and in long-horn beetles Necydalini. The abundance of sensilla in brachyelytrous long-horn beetles Necydalini does not decrease in comparison with macroelytrous Cerambycinae. Strong reduction of the sensory field was found in brachyelytrous Staphylinidae. Lastly, there are beetles lacking the linkage of the elytra down the sutural edge (stenoelytry). Effects of stenoelytry were also not uniform: Oedemera and flying Meloidae have the normal amount of sensilla with respect to their body size, whereas the sensory field in the stenoelytrous Eulosia bombyliformis is 5-6 times less than in chafers of the same size but with normally linking broad elytra.

  11. Fungal Symbionts of the Spruce Bark Beetle Synthesize the Beetle Aggregation Pheromone 2-Methyl-3-buten-2-ol.

    PubMed

    Zhao, Tao; Axelsson, Karolin; Krokene, Paal; Borg-Karlson, Anna-Karin

    2015-09-01

    Tree-killing bark beetles depend on aggregation pheromones to mass-attack their host trees and overwhelm their resistance. The beetles are always associated with phytopathogenic ophiostomatoid fungi that probably assist in breaking down tree resistance, but little is known about if or how much these fungal symbionts contribute to the beetles' aggregation behavior. In this study, we determined the ability of four major fungal symbionts of the spruce bark beetle Ips typographus to produce beetle aggregation pheromones. The fungi were incubated on Norway spruce Picea abies bark, malt agar, or malt agar amended with 0.5% (13)C glucose. Volatiles present in the headspace of each fungus were analyzed for 7 days after incubation using a SPME autosampler coupled to a GC/MS. Two Grosmannia species (G. penicillata and G. europhioides) produced large amounts of 2-methyl-3-buten-2-ol (MB), the major component in the beetles' aggregation pheromone blend, when growing on spruce bark or malt agar. Grosmannia europhioides also incorporated (13)C glucose into MB, demonstrating that the fungi can synthesize MB de novo using glucose as a carbon source. This is the first clear evidence that fungal symbionts of bark beetles can produce components in the aggregation pheromone blend of their beetle vectors. This provides new insight into the possible ecological roles of fungal symbionts in bark beetle systems and may deepen our understanding of species interactions and coevolution in these important biological systems.

  12. Fungal Symbionts of the Spruce Bark Beetle Synthesize the Beetle Aggregation Pheromone 2-Methyl-3-buten-2-ol.

    PubMed

    Zhao, Tao; Axelsson, Karolin; Krokene, Paal; Borg-Karlson, Anna-Karin

    2015-09-01

    Tree-killing bark beetles depend on aggregation pheromones to mass-attack their host trees and overwhelm their resistance. The beetles are always associated with phytopathogenic ophiostomatoid fungi that probably assist in breaking down tree resistance, but little is known about if or how much these fungal symbionts contribute to the beetles' aggregation behavior. In this study, we determined the ability of four major fungal symbionts of the spruce bark beetle Ips typographus to produce beetle aggregation pheromones. The fungi were incubated on Norway spruce Picea abies bark, malt agar, or malt agar amended with 0.5% (13)C glucose. Volatiles present in the headspace of each fungus were analyzed for 7 days after incubation using a SPME autosampler coupled to a GC/MS. Two Grosmannia species (G. penicillata and G. europhioides) produced large amounts of 2-methyl-3-buten-2-ol (MB), the major component in the beetles' aggregation pheromone blend, when growing on spruce bark or malt agar. Grosmannia europhioides also incorporated (13)C glucose into MB, demonstrating that the fungi can synthesize MB de novo using glucose as a carbon source. This is the first clear evidence that fungal symbionts of bark beetles can produce components in the aggregation pheromone blend of their beetle vectors. This provides new insight into the possible ecological roles of fungal symbionts in bark beetle systems and may deepen our understanding of species interactions and coevolution in these important biological systems. PMID:26302987

  13. Lehr's fields of campaniform sensilla in beetles (Coleoptera): functional morphology. III. Modification of elytral mobility or shape in flying beetles.

    PubMed

    Frantsevich, Leonid; Gorb, Stanislav; Radchenko, Vladimir; Gladun, Dmytro

    2015-03-01

    Some flying beetles have peculiar functional properties of their elytra, if compared with the vast majority of beetles. A "typical" beetle covers its pterothorax and the abdomen from above with closed elytra and links closed elytra together along the sutural edges. In the open state during flight, the sutural edges diverge much more than by 90°. Several beetles of unrelated taxa spread wings through lateral incisions on the elytra and turn the elytron during opening about 10-12° (Cetoniini, Scarabaeus, Gymnopleurus) or elevate their elytra without partition (Sisyphus, Tragocerus). The number of campaniform sensilla in their elytral sensory field is diminished in comparison with beetles of closely related taxa lacking that incision. Elytra are very short in rove beetles and in long-horn beetles Necydalini. The abundance of sensilla in brachyelytrous long-horn beetles Necydalini does not decrease in comparison with macroelytrous Cerambycinae. Strong reduction of the sensory field was found in brachyelytrous Staphylinidae. Lastly, there are beetles lacking the linkage of the elytra down the sutural edge (stenoelytry). Effects of stenoelytry were also not uniform: Oedemera and flying Meloidae have the normal amount of sensilla with respect to their body size, whereas the sensory field in the stenoelytrous Eulosia bombyliformis is 5-6 times less than in chafers of the same size but with normally linking broad elytra. PMID:25499796

  14. Beetle horns and horned beetles: emerging models in developmental evolution and ecology.

    PubMed

    Kijimoto, Teiya; Pespeni, Melissa; Beckers, Oliver; Moczek, Armin P

    2013-01-01

    Many important questions in developmental biology increasingly interface with related questions in other biological disciplines such as evolutionary biology and ecology. In this article, we review and summarize recent progress in the development of horned beetles and beetle horns as study systems amenable to the integration of a wide range of approaches, from gene function analysis in the laboratory to population ecological and behavioral studies in the field. Specifically, we focus on three key questions at the current interface of developmental biology, evolutionary biology and ecology: (1) the developmental mechanisms underlying the origin and diversification of novel, complex traits, (2) the relationship between phenotypic diversification and the diversification of genes and transcriptomes, and (3) the role of behavior as a leader or follower in developmental evolution. For each question we discuss how work on horned beetles is contributing to our current understanding of key issues, as well as highlight challenges and opportunities for future studies.

  15. Water capture by a desert beetle.

    PubMed

    Parker, A R; Lawrence, C R

    2001-11-01

    Some beetles in the Namib Desert collect drinking water from fog-laden wind on their backs. We show here that these large droplets form by virtue of the insect's bumpy surface, which consists of alternating hydrophobic, wax-coated and hydrophilic, non-waxy regions. The design of this fog-collecting structure can be reproduced cheaply on a commercial scale and may find application in water-trapping tent and building coverings, for example, or in water condensers and engines.

  16. Water capture by a desert beetle

    NASA Astrophysics Data System (ADS)

    Parker, Andrew R.; Lawrence, Chris R.

    2001-11-01

    Some beetles in the Namib Desert collect drinking water from fog-laden wind on their backs. We show here that these large droplets form by virtue of the insect's bumpy surface, which consists of alternating hydrophobic, wax-coated and hydrophilic, non-waxy regions. The design of this fog-collecting structure can be reproduced cheaply on a commercial scale and may find application in water-trapping tent and building coverings, for example, or in water condensers and engines.

  17. Tenebrio beetles use magnetic inclination compass

    NASA Astrophysics Data System (ADS)

    Vácha, Martin; Drštková, Dana; Půžová, Tereza

    2008-08-01

    Animals that guide directions of their locomotion or their migration routes by the lines of the geomagnetic field use either polarity or inclination compasses to determine the field polarity (the north or south direction). Distinguishing the two compass types is a guideline for estimation of the molecular principle of reception and has been achieved for a number of animal groups, with the exception of insects. A standard diagnostic method to distinguish a compass type is based on reversing the vertical component of the geomagnetic field, which leads to the opposite reactions of animals with two different compass types. In the present study, adults of the mealworm beetle Tenebrio molitor were tested by means of a two-step laboratory test of magnetoreception. Beetles that were initially trained to memorize the magnetic position of the light source preferred, during the subsequent test, this same direction, pursuant geomagnetic cues only. In the following step, the vertical component was reversed between the training and the test. The beetles significantly turned their preferred direction by 180°. Our results brought until then unknown original findings that insects, represented here by the T. molitor species, use—in contrast to another previously researched Arthropod, spiny lobster—the inclination compass.

  18. Influence of water deficit on the molecular responses of Pinus contorta × Pinus banksiana mature trees to infection by the mountain pine beetle fungal associate, Grosmannia clavigera.

    PubMed

    Arango-Velez, Adriana; González, Leonardo M Galindo; Meents, Miranda J; El Kayal, Walid; Cooke, Barry J; Linsky, Jean; Lusebrink, Inka; Cooke, Janice E K

    2014-11-01

    Conifers exhibit a number of constitutive and induced mechanisms to defend against attack by pests and pathogens such as mountain pine beetle (Dendroctonus ponderosae Hopkins) and their fungal associates. Ecological studies have demonstrated that stressed trees are more susceptible to attack by mountain pine beetle than their healthy counterparts. In this study, we tested the hypothesis that water deficit affects constitutive and induced responses of mature lodgepole pine × jack pine hybrids (Pinus contorta Dougl. ex Loud. var. latifolia Engelm. ex S. Wats. × Pinus banksiana Lamb.) to inoculation with the mountain pine beetle fungal associate Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer and Wingfield. The degree of stress induced by the imposed water-deficit treatment was sufficient to reduce photosynthesis. Grosmannia clavigera-induced lesions exhibited significantly reduced dimensions in water-deficit trees relative to well-watered trees at 5 weeks after inoculation. Treatment-associated cellular-level changes in secondary phloem were also observed. Quantitative RT-PCR was used to analyze transcript abundance profiles of 18 genes belonging to four families classically associated with biotic and abiotic stress responses: aquaporins (AQPs), dehydration-responsive element binding (DREB), terpene synthases (TPSs) and chitinases (CHIs). Transcript abundance profiles of a TIP2 AQP and a TINY-like DREB decreased significantly in fungus-inoculated trees, but not in response to water deficit. One TPS, Pcb(+)-3-carene synthase, and the Class II CHIs PcbCHI2.1 and PcbCHI2.2 showed increased expression under water-deficit conditions in the absence of fungal inoculation, while another TPS, Pcb(E)-β-farnesene synthase-like, and two CHIs, PcbCHI1.1 and PcbCHI4.1, showed attenuated expression under water-deficit conditions in the presence of fungal inoculation. The effects were observed both locally and systemically. These results demonstrate

  19. Influence of water deficit on the molecular responses of Pinus contorta × Pinus banksiana mature trees to infection by the mountain pine beetle fungal associate, Grosmannia clavigera.

    PubMed

    Arango-Velez, Adriana; González, Leonardo M Galindo; Meents, Miranda J; El Kayal, Walid; Cooke, Barry J; Linsky, Jean; Lusebrink, Inka; Cooke, Janice E K

    2014-11-01

    Conifers exhibit a number of constitutive and induced mechanisms to defend against attack by pests and pathogens such as mountain pine beetle (Dendroctonus ponderosae Hopkins) and their fungal associates. Ecological studies have demonstrated that stressed trees are more susceptible to attack by mountain pine beetle than their healthy counterparts. In this study, we tested the hypothesis that water deficit affects constitutive and induced responses of mature lodgepole pine × jack pine hybrids (Pinus contorta Dougl. ex Loud. var. latifolia Engelm. ex S. Wats. × Pinus banksiana Lamb.) to inoculation with the mountain pine beetle fungal associate Grosmannia clavigera (Robinson-Jeffrey and Davidson) Zipfel, de Beer and Wingfield. The degree of stress induced by the imposed water-deficit treatment was sufficient to reduce photosynthesis. Grosmannia clavigera-induced lesions exhibited significantly reduced dimensions in water-deficit trees relative to well-watered trees at 5 weeks after inoculation. Treatment-associated cellular-level changes in secondary phloem were also observed. Quantitative RT-PCR was used to analyze transcript abundance profiles of 18 genes belonging to four families classically associated with biotic and abiotic stress responses: aquaporins (AQPs), dehydration-responsive element binding (DREB), terpene synthases (TPSs) and chitinases (CHIs). Transcript abundance profiles of a TIP2 AQP and a TINY-like DREB decreased significantly in fungus-inoculated trees, but not in response to water deficit. One TPS, Pcb(+)-3-carene synthase, and the Class II CHIs PcbCHI2.1 and PcbCHI2.2 showed increased expression under water-deficit conditions in the absence of fungal inoculation, while another TPS, Pcb(E)-β-farnesene synthase-like, and two CHIs, PcbCHI1.1 and PcbCHI4.1, showed attenuated expression under water-deficit conditions in the presence of fungal inoculation. The effects were observed both locally and systemically. These results demonstrate

  20. Endocrine control of exaggerated traits in rhinoceros beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Juvenile hormone (JH) is a key insect growth regulator involved in modulating phenotypically plastic traits in insects such as caste determination in eusocial species, wing polymorphisms in aphids, and mandible size in stag beetle. Male stag beetles have sexually-dimorphic, condition-dependent expre...

  1. Cantharidin Poisoning due to Blister Beetle Ingestion in Children

    PubMed Central

    Al-Binali, Ali M.; Shabana, Medhat; Al-Fifi, Suliman; Dawood, Sami; Shehri, Amer A.; Al-Barki, Ahmed

    2010-01-01

    Cantharidin is an intoxicant found in beetles in the Meloidae (Coleoptera) family. Ingestion may result in haematemesis, impaired level of consciousness, electrolyte disturbance, haematurea and renal impairment. Here, we report two paediatric cases of meloid beetle ingestion resulting in cantharidin poisoning and the clinical presentation of the ensuing intoxication. PMID:21509239

  2. Simulation model of the red flour beetle in flour mills

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Red flour beetle (Tribolium castaneum) is one of the most common insect pests infesting wheat flour mills. Structural treatments such as methyl bromide, sulfuryl fluoride and heat, are used to control the red flour beetle. The structural treatments do not provide any residual action and, thus, any s...

  3. The management of fluid and wave resistances by whirligig beetles.

    PubMed

    Voise, Jonathan; Casas, Jérôme

    2010-02-01

    Whirligig beetles (Coleoptera: Gyrinidae) are semi-aquatic insects with a morphology and propulsion system highly adapted to their life at the air-water interface. When swimming on the water surface, beetles are subject to both fluid resistance and wave resistance. The purpose of this study was to analyse swimming speed, leg kinematics and the capillarity waves produced by whirligig beetles on the water surface in a simple environment. Whirligig beetles of the species Gyrinus substriatus were filmed in a large container, with a high-speed camera. Resistance forces were also estimated. These beetles used three types of leg kinematics, differing in the sequence of leg strokes: two for swimming at low speed and one for swimming at high speed. Four main speed patterns were produced by different combinations of these types of leg kinematics, and the minimum speed for the production of surface waves (23 cm s(-1)) corresponded to an upper limit when beetles used low-speed leg kinematics. Each type of leg kinematics produced characteristic capillarity waves, even if the beetles moved at a speed below 23 cm s(-1). Our results indicate that whirligig beetles use low- and high-speed leg kinematics to avoid maximum drag and swim at speed corresponding to low resistances.

  4. Callosobruchus maculatus: A Seed Beetle with a Future in Schools.

    ERIC Educational Resources Information Center

    Dockery, Michael

    1997-01-01

    Recommends the use of seed beetles for studying animal behavior and provides suggestions for practical and project assignments. Sources for obtaining the beetles and a list of the equipment needed for their study and maintenance are provided. Answers to common concerns are addressed. (DDR)

  5. Formulating entompathogens for control of boring beetles in avocado orchards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A foam formulation of Beauveria bassiana was adapted to control boring beetles in avocado orchards. The two geographically independent avocado growing areas in the United States are threatened by emerging diseases vectored by boring beetles. In the California growing region, Fusarium dieback is vect...

  6. A culture method for darkling beetles, Blapstinus spp. (Coleoptera: Tenebrionidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Darkling beetles, Blapstinus spp., have become a serious pest of Cucurbitaceae crops, especially in California. A culture method was sought to provide large numbers (> 500) of adult beetles of known age and sex that could be used for laboratory testing when needed. A method previously developed for ...

  7. Method for continuously rearing Coccinella lady beetles (Coleoptera: Coccinellidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coccinella novemnotata L., the ninespotted lady beetle, and Coccinella transversoguttata richardsoni Brown, the transverse lady beetle, are predatory species whose abundance has declined significantly over the last few decades in North America. An ex situ system for continuously rearing these two b...

  8. Male-specific sesquiterpenes from Phyllotreta flea beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flea beetles in several genera are known to possess male-specific sesquiterpenes, at least some of which serve as aggregation pheromones that attract both sexes. In continuing research on the chemical ecology of Phyllotreta flea beetles, six new male-specific sesquiterpenes were identified, one fro...

  9. Structure of Phoretic Mite Assemblages Across Subcortical Beetle Species at a Regional Scale.

    PubMed

    Pfammatter, Jesse A; Coyle, David R; Gandhi, Kamal J K; Hernandez, Natalie; Hofstetter, Richard W; Moser, John C; Raffa, Kenneth F

    2016-02-01

    Mites associated with subcortical beetles feed and reproduce within habitats transformed by tree-killing herbivores. Mites lack the ability to independently disperse among these habitats, and thus have evolved characteristics that facilitate using insects as transport between resources. Studies on associations between mites and beetles have historically been beetle-centric, where an assemblage of mite species is characterized on a single beetle species. However, available evidence suggests there may be substantial overlap among mite species on various species of beetles utilizing similar host trees. We assessed the mite communities of multiple beetle species attracted to baited funnel traps in Pinus stands in southern Wisconsin, northern Arizona, and northern Georgia to better characterize mite dispersal and the formation of mite-beetle phoretic associations at multiple scales. We identified approximately 21 mite species totaling 10,575 individuals on 36 beetle species totaling 983 beetles. Of the mites collected, 97% were represented by eight species. Many species of mites were common across beetle species, likely owing to these beetles' common association with trees in the genus Pinus. Most mite species were found on at least three beetle species. Histiostoma spp., Iponemus confusus Lindquist, Histiogaster arborsignis Woodring and Trichouropoda australis Hirschmann were each found on at least seven species of beetles. While beetles had largely similar mite membership, the abundances of individual mite species were highly variable among beetle species within each sampling region. Phoretic mite communities also varied within beetle species between regions, notably for Ips pini (Say) and Ips grandicollis (Eichhoff).

  10. Substrate discrimination in burying beetles, Nicrophorus orbicollis (Coleoptera: Silphidae)

    USGS Publications Warehouse

    Muths, Erin Louise

    1991-01-01

    Burying beetles Nicrophorus orbicollis (Coleoptera: Silphidae) secure and bury small vertebrate carcasses as a food resource for their offspring and themselves. Burial may take place at the point of carcass discovery or at some distance from that site. Burying beetles were tested to determine if they discriminate between different substrates when burying a carcass. Three substrates were presented simultaneously. Substrate one contained soil from typical beetle habitat; substrates two and three contained 2:1 and 5:1 ratios, respectively, of soil and a senescent prairie grass (Panicum virgatum), which added a bulk structural component to the soil. Beetles generally moved and buried the carcass within 24 hours. Results for both paired and individual trials suggest that burying beetles discriminate between substrates, preferring substrates with added bulk over those without.

  11. Curcurbita pepo subspecies delineates striped cucumber beetle (Acalymma vittatum) preference.

    PubMed

    Brzozowski, L; Leckie, B M; Gardner, J; Hoffmann, M P; Mazourek, M

    2016-01-01

    The striped cucumber beetle (Acalymma vittatum (F.)) is a destructive pest of cucurbit crops, and management could be improved by host plant resistance, especially in organic farming systems. However, despite the variation in striped cucumber beetle preference observed within the economically important species, Cucurbita pepo L., plant breeders and entomologists lacked a simple framework to classify and exploit these differences. This study used recent phylogenetic evidence and bioassays to organize striped cucumber beetle preference within C. pepo. Our results indicate preference contrasts between the two agriculturally relevant subspecies: C. pepo subsp. texana and C. pepo subsp. pepo. Plants of C. pepo subsp. pepo were more strongly preferred than C. pepo subsp. texana plants. This structure of beetle preference in C. pepo will allow plant breeders and entomologists to better focus research efforts on host plant non-preference to control striped cucumber beetles. PMID:27347423

  12. Microorganisms in the gut of beetles: evidence from molecular cloning.

    PubMed

    Zhang, Ning; Suh, Sung-Oui; Blackwell, Meredith

    2003-11-01

    We have regularly cultured yeasts from the gut of certain beetles in our ongoing research. In this study cloned PCR products amplified from the gut contents of certain mushroom-feeding and wood-ingesting beetles in four families (Erotylidae, Tenebrionidae, Ciidae, and Passalidae) were sequenced and compared with culture results. Cultural techniques detected some yeasts present in the gut of the beetles, including a Pichia stipitis-like yeast associated with wood-ingesting passalid beetles. Clone sequences similar to several ascomycete yeasts and Malassezia restricta, a fastidious basidiomycetous yeast requiring special growth media, however, were not detected by culturing. Unexpectedly, phylogenetic analysis of additional clone sequences discovered from passalid beetles showed similarity to members of the Parabasalia, protists known from other wood-ingesting insects, termites, and wood roaches. Examination of all gut regions of living passalids, however, failed to reveal parabasalids, and it is possible that they were parasites in the gut tissue present in low numbers.

  13. Curcurbita pepo subspecies delineates striped cucumber beetle (Acalymma vittatum) preference

    PubMed Central

    Brzozowski, L; Leckie, B M; Gardner, J; Hoffmann, M P; Mazourek, M

    2016-01-01

    The striped cucumber beetle (Acalymma vittatum (F.)) is a destructive pest of cucurbit crops, and management could be improved by host plant resistance, especially in organic farming systems. However, despite the variation in striped cucumber beetle preference observed within the economically important species, Cucurbita pepo L., plant breeders and entomologists lacked a simple framework to classify and exploit these differences. This study used recent phylogenetic evidence and bioassays to organize striped cucumber beetle preference within C. pepo. Our results indicate preference contrasts between the two agriculturally relevant subspecies: C. pepo subsp. texana and C. pepo subsp. pepo. Plants of C. pepo subsp. pepo were more strongly preferred than C. pepo subsp. texana plants. This structure of beetle preference in C. pepo will allow plant breeders and entomologists to better focus research efforts on host plant non-preference to control striped cucumber beetles. PMID:27347423

  14. Defensive Chemistry of Lycid Beetles and of Mimetic Cerambycid Beetles that Feed on Them

    PubMed Central

    Eisner, Thomas; Schroeder, Frank C.; Snyder, Noel; Grant, Jacqualine B.; Aneshansley, Daniel J.; Utterback, David; Meinwald, Jerrold; Eisner, Maria

    2008-01-01

    Summary Beetles of the family Lycidae have long been known to be chemically protected. We present evidence that North American species of the lycid genera Calopteron and Lycus are rejected by thrushes, wolf spiders, and orb-weaving spiders, and that they contain a systemic compound that could account, at least in part, for this unacceptability. This compound, a novel acetylenic acid that we named lycidic acid, proved actively deterrent in feeding tests with wolf spiders and coccinellid beetles. Species of Lycus commonly figure as models of mimetic associations. Among their mimics are species of the cerambycid beetle genus Elytroleptus, remarkable because they prey upon the model lycids. We postulated that by doing so Elytroleptus might incorporate the lycidic acid from their prey for their own defense. However, judging from analytical data, the beetles practice no such sequestration, explaining why they remain relatively palatable (in tests with wolf spiders) even after having fed on lycids. Chemical analyses also showed the lycids to contain pyrazines, such as were already known from other Lycidae, potent odorants that could serve in an aposematic capacity to forestall predatory attacks. PMID:18698369

  15. Predatory aquatic beetles, suitable trace elements bioindicators.

    PubMed

    Burghelea, Carmen I; Zaharescu, Dragos G; Hooda, Peter S; Palanca-Soler, Antonio

    2011-05-01

    Predatory aquatic beetles are common colonizers of natural and managed aquatic environments. While as important components of the aquatic food webs they are prone to accumulate trace elements, they have been largely neglected from metal uptake studies. We aim to test the suitability of three dytiscid species, i.e.Hydroglyphus pusillus, Laccophilus minutus and Rhantus suturalis, as trace elements (Al, As, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Se and Zn) bioindicators. The work was carried out in a case area representing rice paddies and control sites (reservoirs) from an arid region known for its land degradation (Monegros, NE Spain). Categorical principal component analysis (CATPCA) was tested as a nonlinear approach to identify significant relationships between metals, species and habitat conditions so as to examine the ability of these species to reflect differences in metal uptake. Except Se and As, the average concentrations of all other elements in the beetles were higher in the rice fields than in the control habitats. The CATPCA determined that H. pusillus had high capacity to accumulate Fe, Ni and Mn regardless of the habitat type, and hence may not be capable of distinguishing habitat conditions with regards to these metals. On the other hand, L. minutus was found less sensitive for Se in non-managed habitats (i.e. reservoirs), while R. suturalis was good in accumulating Al, Mo and Pb in rice fields. The latter seems to be a promising bioindicator of metal enrichment in rice fields. We conclude that predatory aquatic beetles are good candidates for trace elements bioindication in impacted and non-impacted environments and can be used in environmental monitoring studies. CATPCA proved to be a reliable approach to unveil trends in metal accumulation in aquatic invertebrates according to their habitat status.

  16. Brilliant Whiteness in Ultrathin Beetle Scales

    NASA Astrophysics Data System (ADS)

    Vukusic, Pete; Hallam, Benny; Noyes, Joe

    2007-01-01

    The colored appearances of animals are controlled by pigmentation, highly periodic ultrastructure, or a combination of both. Whiteness, however, is less common and is generated by neither of these, because it requires scattering processes appropriate for all visible wavelengths. We report whiteness resulting from a three-dimensional photonic solid in the scales of Cyphochilus spp. beetles. Their scales are characterized by their exceptional whiteness, their perceived brightness, and their optical brilliance, but they are only 5 micrometers thick. This thickness is at least two orders of magnitude thinner than common synthetic systems designed for equivalent-quality whiteness.

  17. Brilliant whiteness in ultrathin beetle scales.

    PubMed

    Vukusic, Pete; Hallam, Benny; Noyes, Joe

    2007-01-19

    The colored appearances of animals are controlled by pigmentation, highly periodic ultrastructure, or a combination of both. Whiteness, however, is less common and is generated by neither of these, because it requires scattering processes appropriate for all visible wavelengths. We report whiteness resulting from a three-dimensional photonic solid in the scales of Cyphochilus spp. beetles. Their scales are characterized by their exceptional whiteness, their perceived brightness, and their optical brilliance, but they are only 5 micrometers thick. This thickness is at least two orders of magnitude thinner than common synthetic systems designed for equivalent-quality whiteness. PMID:17234940

  18. Effect of water stress and fungal inoculation on monoterpene emission from an historical and a new pine host of the mountain pine beetle.

    PubMed

    Lusebrink, Inka; Evenden, Maya L; Blanchet, F Guillaume; Cooke, Janice E K; Erbilgin, Nadir

    2011-09-01

    The mountain pine beetle (Dendroctonus ponderosae, MPB) has killed millions of lodgepole pine (Pinus contorta) trees in Western Canada, and recent range expansion has resulted in attack of jack pine (Pinus banksiana) in Alberta. Establishment of MPB in the Boreal forest will require use of jack pine under a suite of environmental conditions different from those it typically encounters in its native range. Lodgepole and jack pine seedlings were grown under controlled environment conditions and subjected to either water deficit or well watered conditions and inoculated with Grosmannia clavigera, a MPB fungal associate. Soil water content, photosynthesis, stomatal conductance, and emission of volatile organic compounds (VOCs) were monitored over the duration of the six-week study. Monoterpene content of bark and needle tissue was measured at the end of the experiment. β-Phellandrene, the major monoterpene in lodgepole pine, was almost completely lacking in the volatile emission profile of jack pine. The major compound in jack pine was α-pinene. The emission of both compounds was positively correlated with stomatal conductance. 3-Carene was emitted at a high concentration from jack pine seedlings, which is in contrast to monoterpene profiles of jack pine from more southern and eastern parts of its range. Fungal inoculation caused a significant increase in total monoterpene emission in water deficit lodgepole pine seedlings right after its application. By 4 weeks into the experiment, water deficit seedlings of both species released significantly lower levels of total monoterpenes than well watered seedlings. Needle tissue contained lower total monoterpene content than bark. Generally, monoterpene tissue content increased over time independent from any treatment. The results suggest that monoterpenes that play a role in pine-MPB interactions differ between lodgepole and jack pine, and also that they are affected by water availability. PMID:21874397

  19. Simulated impacts of mountain pine beetle and wildfire disturbances on forest vegetation composition and carbon stocks in the Southern Rocky Mountains

    USGS Publications Warehouse

    Caldwell, Megan K.; Hawbaker, Todd J.; Briggs, Jenny S.; Cigan, P.W.; Stitt, Susan

    2013-01-01

    Forests play an important role in sequestering carbon and offsetting anthropogenic greenhouse gas emissions, but changing disturbance regimes may compromise the capability of forests to store carbon. In the Southern Rocky Mountains, a recent outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused levels of tree mortality that are unprecedented in recorded history. To evaluate the long-term impacts of both this insect outbreak and another characteristic disturbance in these forests, high-severity wildfire, we simulated potential changes in species composition and carbon stocks using the Forest Vegetation Simulator (FVS). Simulations were completed for 3 scenarios (no disturbance, actual MPB infestation, and modeled wildfire) using field data collected in 2010 at 97 plots in the lodgepole pine-dominated forests of eastern Grand County, Colorado, which were heavily impacted by MPB after 2002. Results of the simulations showed that (1) lodgepole pine remained dominant over time in all scenarios, with basal area recovering to pre-disturbance levels 70–80 yr after disturbance; (2) wildfire caused a greater magnitude of change than did MPB in both patterns of succession and distribution of carbon among biomass pools; (3) levels of standing-live carbon returned to pre-disturbance conditions after 40 vs. 50 yr following MPB vs. wildfire disturbance, respectively, but took 120 vs. 150 yr to converge with conditions in the undisturbed scenario. Lodgepole pine forests appear to be relatively resilient to both of the disturbances we modeled, although changes in climate, future disturbance regimes, and other factors may significantly affect future rates of regeneration and ecosystem response.

  20. Effect of water stress and fungal inoculation on monoterpene emission from an historical and a new pine host of the mountain pine beetle.

    PubMed

    Lusebrink, Inka; Evenden, Maya L; Blanchet, F Guillaume; Cooke, Janice E K; Erbilgin, Nadir

    2011-09-01

    The mountain pine beetle (Dendroctonus ponderosae, MPB) has killed millions of lodgepole pine (Pinus contorta) trees in Western Canada, and recent range expansion has resulted in attack of jack pine (Pinus banksiana) in Alberta. Establishment of MPB in the Boreal forest will require use of jack pine under a suite of environmental conditions different from those it typically encounters in its native range. Lodgepole and jack pine seedlings were grown under controlled environment conditions and subjected to either water deficit or well watered conditions and inoculated with Grosmannia clavigera, a MPB fungal associate. Soil water content, photosynthesis, stomatal conductance, and emission of volatile organic compounds (VOCs) were monitored over the duration of the six-week study. Monoterpene content of bark and needle tissue was measured at the end of the experiment. β-Phellandrene, the major monoterpene in lodgepole pine, was almost completely lacking in the volatile emission profile of jack pine. The major compound in jack pine was α-pinene. The emission of both compounds was positively correlated with stomatal conductance. 3-Carene was emitted at a high concentration from jack pine seedlings, which is in contrast to monoterpene profiles of jack pine from more southern and eastern parts of its range. Fungal inoculation caused a significant increase in total monoterpene emission in water deficit lodgepole pine seedlings right after its application. By 4 weeks into the experiment, water deficit seedlings of both species released significantly lower levels of total monoterpenes than well watered seedlings. Needle tissue contained lower total monoterpene content than bark. Generally, monoterpene tissue content increased over time independent from any treatment. The results suggest that monoterpenes that play a role in pine-MPB interactions differ between lodgepole and jack pine, and also that they are affected by water availability.

  1. Assessing Mountain Pine Beetle infestation patterns in space and time using high resolution QuickBird imagery and LiDAR

    NASA Astrophysics Data System (ADS)

    Kaiser, K. E.; McGlynn, B. L.; Emanuel, R. E.

    2013-12-01

    The recent mountain pine beetle (Dendroctonus ponderosae) epidemic that has affected millions of hectares in the Rocky Mountains gives us a unique opportunity to consider the environmental variables influencing the spatial extent and pattern of vegetation disturbance through time. This work builds on our previous research at the USFS Tenderfoot Creek Experimental Forest (TCEF), Montana documenting the correlation between landscape position wetness state and tree mortality in 2010. We calibrated QuickBird remote sensing imagery with leaf level measures by developing an extensive spectral library for TCEF vegetation that includes infestation state of lodgepole pine (LPP). Vegetation indices were applied to the QuickBird imagery to determine the extent and pattern of infestation across TCEF. In addition, we calculated LiDAR (light detection and ranging) based topography and vegetation structure indices for joint topographic, vegetation, and disturbance analyses. We found that trees in locations with specific landscape characteristics such as small contributing areas and south facing slopes were significantly more likely to exhibit signs of infestation. We now present new results using change detection analysis documenting how these infestation patterns evolve over 4 years. We assess how patterns of infestation change through time in relation to landscape variables and changing stand dynamics due to prior years of infestation. Our efforts to monitor vegetation mortality spatially and temporally provide a context for assessing how a changing population of host (LPP), prior management practices, and landscape environmental variables may effect the progression of infestation, which in turn could affect watershed ecohydrology via altered energy, water, and biogeochemical cycles.

  2. Simulated impacts of mountain pine beetle and wildfire disturbances on forest vegetation composition and carbon stocks in the Southern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Caldwell, M. K.; Hawbaker, T. J.; Briggs, J. S.; Cigan, P. W.; Stitt, S.

    2013-12-01

    Forests play an important role in sequestering carbon and offsetting anthropogenic greenhouse gas emissions, but changing disturbance regimes may compromise the capability of forests to store carbon. In the Southern Rocky Mountains, a recent outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused remarkable levels of tree mortality. To evaluate the long-term impacts of both this insect outbreak and another characteristic disturbance in these forests, high-severity wildfire, we simulated potential changes in species composition and carbon stocks using the Forest Vegetation Simulator (FVS). Simulations were completed for 3 scenarios (no disturbance, actual MPB infestation, and modeled wildfire) using field data collected in 2010 at 97 plots in the lodgepole-pine-dominated forests of eastern Grand County, Colorado, which were heavily impacted by MPB after 2002. Results of the simulations showed that (1) lodgepole pine remained dominant over time in all scenarios, with basal area recovering to pre-disturbance levels 70-80 yr after disturbance; (2) wildfire caused a greater magnitude of change than did MPB in both patterns of succession and distribution of carbon among biomass pools; (3) levels of standing-live carbon returned to pre-disturbance conditions after 40 vs. 50 yr following MPB vs. wildfire disturbance, respectively, but took 120 vs. 150 yr to converge with conditions in the undisturbed scenario. Lodgepole pine forests appear to be relatively resilient to both of the disturbances we modeled, although changes in climate, future disturbance regimes, and other factors may significantly affect future rates of regeneration and ecosystem response.

  3. Simulated impacts of mountain pine beetle and wildfire disturbances on forest vegetation composition and carbon stocks in the Southern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Caldwell, M. K.; Hawbaker, T. J.; Briggs, J. S.; Cigan, P. W.; Stitt, S.

    2013-08-01

    Forests play an important role in sequestering carbon and offsetting anthropogenic greenhouse gas emissions, but changing disturbance regimes may compromise the capability of forests to store carbon. In the Southern Rocky Mountains, a recent outbreak of mountain pine beetle (Dendroctonus ponderosae; MPB) has caused levels of tree mortality that are unprecedented in recorded history. To evaluate the long-term impacts of both this insect outbreak and another characteristic disturbance in these forests, high-severity wildfire, we simulated potential changes in species composition and carbon stocks using the Forest Vegetation Simulator (FVS). Simulations were completed for 3 scenarios (no disturbance, actual MPB infestation, and modeled wildfire) using field data collected in 2010 at 97 plots in the lodgepole pine-dominated forests of eastern Grand County, Colorado, which were heavily impacted by MPB after 2002. Results of the simulations showed that (1) lodgepole pine remained dominant over time in all scenarios, with basal area recovering to pre-disturbance levels 70-80 yr after disturbance; (2) wildfire caused a greater magnitude of change than did MPB in both patterns of succession and distribution of carbon among biomass pools; (3) levels of standing-live carbon returned to pre-disturbance conditions after 40 vs. 50 yr following MPB vs. wildfire disturbance, respectively, but took 120 vs. 150 yr to converge with conditions in the undisturbed scenario. Lodgepole pine forests appear to be relatively resilient to both of the disturbances we modeled, although changes in climate, future disturbance regimes, and other factors may significantly affect future rates of regeneration and ecosystem response.

  4. Transcriptome resources and functional characterization of monoterpene synthases for two host species of the mountain pine beetle, lodgepole pine (Pinus contorta) and jack pine (Pinus banksiana)

    PubMed Central

    2013-01-01

    Background The mountain pine beetle (MPB, Dendroctonus ponderosae) epidemic has affected lodgepole pine (Pinus contorta) across an area of more than 18 million hectares of pine forests in western Canada, and is a threat to the boreal jack pine (Pinus banksiana) forest. Defence of pines against MPB and associated fungal pathogens, as well as other pests, involves oleoresin monoterpenes, which are biosynthesized by families of terpene synthases (TPSs). Volatile monoterpenes also serve as host recognition cues for MPB and as precursors for MPB pheromones. The genes responsible for terpene biosynthesis in jack pine and lodgepole pine were previously unknown. Results We report the generation and quality assessment of assembled transcriptome resources for lodgepole pine and jack pine using Sanger, Roche 454, and Illumina sequencing technologies. Assemblies revealed transcripts for approximately 20,000 - 30,000 genes from each species and assembly analyses led to the identification of candidate full-length prenyl transferase, TPS, and P450 genes of oleoresin biosynthesis. We cloned and functionally characterized, via expression of recombinant proteins in E. coli, nine different jack pine and eight different lodgepole pine mono-TPSs. The newly identified lodgepole pine and jack pine mono-TPSs include (+)-α-pinene synthases, (-)-α-pinene synthases, (-)-β-pinene synthases, (+)-3-carene synthases, and (-)-β-phellandrene synthases from each of the two species. Conclusion In the absence of genome sequences, transcriptome assemblies are important for defence gene discovery in lodgepole pine and jack pine, as demonstrated here for the terpenoid pathway genes. The product profiles of the functionally annotated mono-TPSs described here can account for the major monoterpene metabolites identified in lodgepole pine and jack pine. PMID:23679205

  5. Dung beetles ignore landmarks for straight-line orientation.

    PubMed

    Dacke, Marie; Byrne, Marcus; Smolka, Jochen; Warrant, Eric; Baird, Emily

    2013-01-01

    Upon locating a suitable dung pile, ball-rolling dung beetles shape a piece of dung into a ball and roll it away in a straight line. This guarantees that they will not return to the dung pile, where they risk having their ball stolen by other beetles. Dung beetles are known to use celestial compass cues such as the sun, the moon and the pattern of polarised light formed around these light sources to roll their balls of dung along straight paths. Here, we investigate whether terrestrial landmarks have any influence on straight-line orientation in dung beetles. We find that the removal or re-arrangement of landmarks has no effect on the beetle's orientation precision. Celestial compass cues dominate straight-line orientation in dung beetles so strongly that, under heavily overcast conditions or when prevented from seeing the sky, the beetles can no longer orient along straight paths. To our knowledge, this is the only animal with a visual compass system that ignores the extra orientation precision that landmarks can offer.

  6. Phylogeny of world stag beetles (Coleoptera: Lucanidae) reveals a Gondwanan origin of Darwin's stag beetle.

    PubMed

    Kim, Sang Il; Farrell, Brian D

    2015-05-01

    Stag beetles (family Lucanidae Latreille, 1804) are one of the earliest branching lineages of scarab beetles that are characterized by the striking development of the male mandibles. Despite stag beetles' popularity among traditional taxonomists and amateur collectors, there has been almost no study of lucanid relationships and evolution. Entomologists, including Jeannel (1942), have long recognized resemblance between the austral stag beetles of the tribes Chiasognathini, Colophonini, Lamprimini, Pholidotini, Rhyssonotini, and Streptocerini, but this hypothesis of their close relationship across the continents has never been tested. To gain further insight into lucanid phylogeny and biogeography, we reconstructed the first molecular phylogeny of world stag beetles using DNA sequences from mitochondrial 16S rDNA, nuclear 18S and 28S rDNA, and the nuclear protein-coding (NPC) gene wingless for 93 lucanid species representing all extant subfamilies and 24 out of the 27 tribes, together with 14 representative samples of other early branching scarabaeoid families and two staphyliniform beetle families as outgroups. Both Bayesian inference (BI) and maximum likelihood inference (MLI) strongly supported the monophyly of Lucanidae sensu lato that includes Diphyllostomatidae. Within Lucanidae sensu stricto, the subfamilies Lucaninae and Lampriminae appeared monophyletic under both methods of phylogenetic inferences; however, Aesalinae and Syndesinae were found to be polyphyletic. A time-calibrated phylogeny based on five fossil data estimated the origin of crown group Lucanidae as circa 160 million years ago (MYA). Divergence between the Neotropical and Australasian groups of the Chiasognathini was estimated to be circa 47MYA, with the South African Colophonini branching off from the ancient Chiasognathini lineage around 87MYA. Another Gondwanan relationship was recovered between the Australasian Eucarteria and the Neotropical Casignetus, which diverged circa 58MYA. Lastly

  7. Red List of beetles of the Wadden Sea Area

    NASA Astrophysics Data System (ADS)

    Mahler, V.; Suikat, R.; Aßmann, Th.

    1996-10-01

    As no data on beetles in the Wadden Sea area are available from The Netherlands, the trilateral status of threat only refers to the Danish and German part of the Wadden Sea. In this area, in total, 238 species of beetles are threatened in at least one subregion. Of these, 189 species are threatened in the entire area and are therefore placed on the trilateral Red List. 4 species are (probably) extinct in the entire Wadden Sea area. The status of 24 species of beetles is (probably) critical, 46 species are (probably) endangered, the status of 86 species is (probably) vulnerable and of 29 species (probably) susceptible.

  8. Atlas of Iberian water beetles (ESACIB database).

    PubMed

    Sánchez-Fernández, David; Millán, Andrés; Abellán, Pedro; Picazo, Félix; Carbonell, José A; Ribera, Ignacio

    2015-01-01

    The ESACIB ('EScarabajos ACuáticos IBéricos') database is provided, including all available distributional data of Iberian and Balearic water beetles from the literature up to 2013, as well as from museum and private collections, PhD theses, and other unpublished sources. The database contains 62,015 records with associated geographic data (10×10 km UTM squares) for 488 species and subspecies of water beetles, 120 of them endemic to the Iberian Peninsula and eight to the Balearic Islands. This database was used for the elaboration of the "Atlas de los Coleópteros Acuáticos de España Peninsular". In this dataset data of 15 additional species has been added: 11 that occur in the Balearic Islands or mainland Portugal but not in peninsular Spain and an other four with mainly terrestrial habits within the genus Helophorus (for taxonomic coherence). The complete dataset is provided in Darwin Core Archive format. PMID:26448717

  9. "Excess Water" Following Deforestation by Beetle Kill?

    NASA Astrophysics Data System (ADS)

    Hyde, K.; Miller, S. N.; Anderson-Sprecher, R.; Ewers, B. E.; Speckman, H.

    2014-12-01

    Deforestation resulting from tree mortality by insects and disease may reduce transpiration demand and increase available water in mountain environments throughout. We tested this hypothesis using three large catchments (97-407 km2) located in the Snowy Mountains of Wyoming where hydrology is snowmelt dominated. An epidemic of spruce bark beetle and associated tree mortality emerged in 2006 and has since impacted 60 to 80% of basal area of the spruce-fir and mixed conifer forests. A 25-year continuous record (1998-2013) of daily snowfall, temperature, and stream discharge data between 1 April and 30 September of each year were available for each catchment. We used quantile regression and multivariate time series analysis first to control for the effects of temperature and snow water equivalent on the timing and magnitude of discharge and then to test for changes in discharge trends since 2006. We found no compelling evidence of changes in discharge trends associated with the onset of the beetle epidemic independent of snowmelt trends. Several factors could explain this apparent lack of "excess water" following tree mortality by insects and disease. Any increases in water may be scale dependent, a local phenomenon that does not transfer through large catchments. Other vegetation including young cohorts of affected tree species, shrubs, and herbaceous cover may respond robustly to the open canopy and utilize soil water previously consumed by the infected trees.

  10. Dew condensation on desert beetle skin.

    PubMed

    Guadarrama-Cetina, J; Mongruel, A; Medici, M-G; Baquero, E; Parker, A R; Milimouk-Melnytchuk, I; González-Viñas, W; Beysens, D

    2014-11-01

    Some tenebrionind beetles inhabiting the Namib desert are known for using their body to collect water droplets from wind-blown fogs. We aim to determine whether dew water collection is also possible for desert insects. For this purpose, we investigated the infra-red emissivity, and the wetting and structural properties, of the surface of the elytra of a preserved specimen of Physasterna cribripes (Tenebrionidæ) beetle, where the macro-structure appears as a series of "bumps", with "valleys" between them. Dew formation experiments were carried out in a condensation chamber. The surface properties (infra-red emissivity, wetting properties) were dominated by the wax at the elytra surface and, to a lower extent, its micro-structure. We performed scanning electron microscope on histological sections and determined the infra-red emissivity using a scanning pyrometer. The emissivity measured (0.95±0.07 between 8-14 μm) was close to the black body value. Dew formation occurred on the insect's elytra, which can be explained by these surface properties. From the surface coverage of the condensed drops it was found that dew forms primarily in the valleys between the bumps. The difference in droplet nucleation rate between bumps and valleys can be attributed to the hexagonal microstructure on the surface of the valleys, whereas the surface of the bumps is smooth. The drops can slide when they reach a critical size, and be collected at the insect's mouth.

  11. The bark beetle holobiont: why microbes matter.

    PubMed

    Six, Diana L

    2013-07-01

    All higher organisms are involved in symbioses with microbes. The importance of these partnerships has led to the concept of the holobiont, defined as the animal or plant with all its associated microbes. Indeed, the interactions between insects and symbionts form much of the basis for the success and diversity of this group of arthropods. Insects rely on microbes to perform basic life functions and to exploit resources and habitats. By "partnering" with microbes, insects access new genomic variation instantaneously allowing the exploitation of new adaptive zones, influencing not only outcomes in ecological time, but the degree of innovation and change that occurs over evolutionary time. In this review, I present a brief overview of the importance of insect-microbe holobionts to illustrate how critical an understanding of the holobiont is to understanding the insect host and it interactions with its environment. I then review what is known about the most influential insect holobionts in many forest ecosystems-bark beetles and their microbes-and how new approaches and technologies are allowing us to illuminate how these symbioses function. Finally, I discuss why it will be critical to study bark beetles as a holobiont to understand the ramifications and extent of anthropogenic change in forest ecosystems.

  12. Atlas of Iberian water beetles (ESACIB database)

    PubMed Central

    Sánchez-Fernández, David; Millán, Andrés; Abellán, Pedro; Picazo, Félix; Carbonell, José A.; Ribera, Ignacio

    2015-01-01

    Abstract The ESACIB (‘EScarabajos ACuáticos IBéricos’) database is provided, including all available distributional data of Iberian and Balearic water beetles from the literature up to 2013, as well as from museum and private collections, PhD theses, and other unpublished sources. The database contains 62,015 records with associated geographic data (10×10 km UTM squares) for 488 species and subspecies of water beetles, 120 of them endemic to the Iberian Peninsula and eight to the Balearic Islands. This database was used for the elaboration of the “Atlas de los Coleópteros Acuáticos de España Peninsular”. In this dataset data of 15 additional species has been added: 11 that occur in the Balearic Islands or mainland Portugal but not in peninsular Spain and an other four with mainly terrestrial habits within the genus Helophorus (for taxonomic coherence). The complete dataset is provided in Darwin Core Archive format. PMID:26448717

  13. Spatial scaling of mountain pine beetle infestations.

    PubMed

    Gamarra, J G P; He, F

    2008-07-01

    1. The relationship between occupancy and spatial contagion during the spread of eruptive and invasive species demands greater study, as it could lead to improved prediction of ecosystem damage. 2. We applied a recently developed model that links occupancy and its fractal dimension to model the spatial distribution of mountain pine beetle infestations in British Columbia, Canada. We showed that the distribution of infestation was scale-invariant in at least 24 out of 37 years (mostly in epidemic years), and presented some degree of scale-invariance in the rest. There was a general logarithmic relationship between fractal dimension and infestation occupancy. Based on the scale-invariance assumption, we further assessed the interrelationships for several landscape metrics, such as correlation length, maximum cluster size, total edge length and total number of clusters. 3. The scale-invariance assumption allows fitting the above metrics, and provides a framework to establish the scaling relationship between occupancy and spatial contagion. 4. We concluded that scale-invariance dominates the spread of mountain pine beetle. In this context, spatial aggregation can be predicted from occupancy, hence occupancy is the only variable one needs to know in order to predict the spatial distributions of populations. This supports the hypothesis that fractal dispersal kernels may be abundant among outbreaks of pests and invasive species.

  14. Dew condensation on desert beetle skin.

    PubMed

    Guadarrama-Cetina, J; Mongruel, A; Medici, M-G; Baquero, E; Parker, A R; Milimouk-Melnytchuk, I; González-Viñas, W; Beysens, D

    2014-11-01

    Some tenebrionind beetles inhabiting the Namib desert are known for using their body to collect water droplets from wind-blown fogs. We aim to determine whether dew water collection is also possible for desert insects. For this purpose, we investigated the infra-red emissivity, and the wetting and structural properties, of the surface of the elytra of a preserved specimen of Physasterna cribripes (Tenebrionidæ) beetle, where the macro-structure appears as a series of "bumps", with "valleys" between them. Dew formation experiments were carried out in a condensation chamber. The surface properties (infra-red emissivity, wetting properties) were dominated by the wax at the elytra surface and, to a lower extent, its micro-structure. We performed scanning electron microscope on histological sections and determined the infra-red emissivity using a scanning pyrometer. The emissivity measured (0.95±0.07 between 8-14 μm) was close to the black body value. Dew formation occurred on the insect's elytra, which can be explained by these surface properties. From the surface coverage of the condensed drops it was found that dew forms primarily in the valleys between the bumps. The difference in droplet nucleation rate between bumps and valleys can be attributed to the hexagonal microstructure on the surface of the valleys, whereas the surface of the bumps is smooth. The drops can slide when they reach a critical size, and be collected at the insect's mouth. PMID:25403836

  15. Phenotypic plasticity in a willow leaf beetle depends on host plant species: release and recognition of beetle odors.

    PubMed

    Austel, Nadine; Reinecke, Andreas; Björkman, Christer; Hilker, Monika; Meiners, Torsten

    2015-02-01

    Aggregation behavior of herbivorous insects is mediated by a wide range of biotic and abiotic factors. It has been suggested that aggregation behavior of the blue willow leaf beetle Phratora vulgatissima is mediated by both host plant odor and by odor released by the beetles. Previous studies show that the beetles respond to plant odors according to their prior host plant experiences. Here, we analyzed the effect of the host plant species on odor released and perceived by adult P. vulgatissima. The major difference between the odor of beetles feeding on salicin-rich and salicin-poor host plants was the presence of salicylaldehyde in the odor of the former, where both males and females released this compound. Electrophysiological studies showed that the intensity of responses to single components of odor released by beetles was sex specific and dependent on the host plant species with which the beetles were fed. Finally, behavioral studies revealed that males feeding on salicin-rich willows were attracted by salicylaldehyde, whereas females did not respond behaviorally to this compound, despite showing clear antennal responses to it. Finally, the ecological relevance of the influence of a host plant species on the plasticity of beetle odor chemistry, perception, and behavior is discussed.

  16. Micro-structure and frictional characteristics of beetle?s joint

    NASA Astrophysics Data System (ADS)

    Dai, Zhendong; Gorb, Stanislav N.

    2004-01-01

    Geometric and micro-structure design, tribology properties of beetle joints were experimentally studied, which aimed to enlighten ideas for the joint design of MEMS. The observation by using SEM and microscopy suggested that beetle’s joints consist of a concave surface matched with a convex surface. The heads of the beetles, rubbing with flat glass, were tested in fresh and dried statuses and compared with sapphire ball with flat glass. Frictional coefficient of the joint material on glass was significantly lower than that of the sapphire sphere on glass. The material of the joint cuticle for convex surface is rather stiff (the elastic modulus 4.5 Gpa) and smooth. The surface is hydrophobic (the contact angle of distilled water was 88.3°). It is suggested here that the high stiffness of the joint material and hydrophobicity of the joint surface are parts of the mechanism minimizing friction in insect joints.

  17. The artificial beetle, or a brief manifesto for engineered biomimicry

    NASA Astrophysics Data System (ADS)

    Bartl, Michael H.; Lakhtakia, Akhlesh

    2015-03-01

    The artificial beetle is possibly the Holy Grail for practitioners of engineered biomimicry. An artificial beetle could gather and relay data and images from compromised environments on earth and other planets to decision makers. It could also be used for surveillance of foes and friends alike, and will require ethical foresight and oversight. What would it take to develop an artificial beetle? Several biotemplating techniques can be harnessed for the replication of external structural features of beetle bodies, and thus preserve functionalities such as coloration of the exoskeleton and the hydrophobicity of wings. The body cavity must host a power supply, motors to move the wings for flight, sensors to capture ambient conditions and images, and data transmitters and receivers to communicate with a remote command center. All of these devices must be very small and reliable.

  18. Physiological benefits of nectar-feeding by a predatory beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Extrafloral nectar is an important food source for many animals, including predatory lady beetles (Coleoptera: Coccinellidae), although the physiological benefits of nectar consumption are poorly understood for most consumers. Under laboratory conditions, we confined new females of Coleomegilla macu...

  19. Pheromone Chemistry of the Smaller European Elm Bark Beetle.

    ERIC Educational Resources Information Center

    Beck, Keith

    1978-01-01

    Discusses the aggregation pheromone of the smaller European elm bark beetle, Scolytus multistriatus (Marsham), with emphasis on information that could be used in the classroom as a practical application of organic chemistry. (Author/GA)

  20. Biologically inspired optics: analog semiconductor model of the beetle exoskeleton

    NASA Astrophysics Data System (ADS)

    Buhl, Kaia; Roth, Zachary; Srinivasan, Pradeep; Rumpf, Raymond; Johnson, Eric

    2008-08-01

    Evolution in nature has produced through adaptation a wide variety of distinctive optical structures in many life forms. For example, pigment differs greatly from the observed color of most beetles because their exoskeletons contain multilayer coatings. The green beetle is disguised in a surrounding leaf by having a comparable reflection spectrum as the leaves. The Manuka and June beetle have a concave structure where light incident at any angle on the concave structures produce matching reflection spectra. In this work, semiconductor processing methods were used to duplicate the structure of the beetle exoskeleton. This was achieved by combining analog lithography with a multilayer deposition process. The artificial exoskeleton, 3D concave multilayer structure, demonstrates a wide field of view with a unique spectral response. Studying and replicating these biologically inspired nanostructures may lead to new knowledge for fabrication and design of new and novel nano-photonic devices, as well as provide valuable insight to how such phenomenon is exploited.

  1. Mechanical properties of the beetle elytron, a biological composite material

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We determined the relationship between composition and mechanical properties of elytral (modified forewing) cuticle of the beetles Tribolium castaneum and Tenebrio molitor. Elytra of both species have similar mechanical properties at comparable stages of maturation (tanning). Shortly after adult ecl...

  2. Two Additional Invasive Scarabaeoid Beetles (Coleoptera: Scarabaeidae: Dynastinae) in Hawaii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Two species of dynastine scarab beetles are reported for the first time on the island of Hawaii: the Pasadena masked chafer, Cyclocephala pasadenae (Casey)(Scarabaeidae: Dynastinae: Cyclocephalini) and the Temnorhynchus retusus (Fabricius)(Scarabaeidae: Dynastinae: Pentodontini). The Pasadena mask...

  3. Big dung beetles dig deeper: trait-based consequences for faecal parasite transmission.

    PubMed

    Gregory, Nichar; Gómez, Andrés; Oliveira, Trícia Maria F de S; Nichols, Elizabeth

    2015-02-01

    Observational evidence suggests that burial of faeces by dung beetles negatively influences the transmission of directly transmitted gastrointestinal helminths. However, the mechanistic basis for these interactions is poorly characterised, limiting our ability to understand relationships between beetle community composition and helminth transmission. We demonstrate that beetle body size and sex significantly impact tunnel depth, a key variable affecting parasite survival. Additionally, high parasite loads reduce the depth of beetle faeces burial, suggesting that the local prevalence of parasites infecting beetles may impact beetle ecosystem function. Our study represents a first step towards a mechanistic understanding of a potentially epidemiologically relevant ecosystem function.

  4. Untwisting the polarization properties of light reflected by scarab beetles

    NASA Astrophysics Data System (ADS)

    McDonald, Luke T.; Finlayson, Ewan D.; Vukusic, Peter

    2015-03-01

    The spectral and angle-dependent optical properties of two scarab beetle species belonging to the genus Chrysina are presented. The species display broadband reflectivity and selectively reflect left-circularly polarized light. We use electron microscopy to detail the left-handed, twisted lamellar structure present in these biological systems and imaging scatterometry to characterize their bidirectional reflectance distribution function. We show that the broadband nature of the beetles' reflectance originates due to the range of pitch dimensions found in the structure.

  5. Spectral information as an orientation cue in dung beetles.

    PubMed

    El Jundi, Basil; Foster, James J; Byrne, Marcus J; Baird, Emily; Dacke, Marie

    2015-11-01

    During the day, a non-uniform distribution of long and short wavelength light generates a colour gradient across the sky. This gradient could be used as a compass cue, particularly by animals such as dung beetles that rely primarily on celestial cues for orientation. Here, we tested if dung beetles can use spectral cues for orientation by presenting them with monochromatic (green and UV) light spots in an indoor arena. Beetles kept their original bearing when presented with a single light cue, green or UV, or when presented with both light cues set 180° apart. When either the UV or the green light was turned off after the beetles had set their bearing in the presence of both cues, they were still able to maintain their original bearing to the remaining light. However, if the beetles were presented with two identical green light spots set 180° apart, their ability to maintain their original bearing was impaired. In summary, our data show that ball-rolling beetles could potentially use the celestial chromatic gradient as a reference for orientation. PMID:26538537

  6. Mutualism Between Fire Ants and Mealybugs Reduces Lady Beetle Predation.

    PubMed

    Cheng, Shoujie; Zeng, Ling; Xu, Yijuan

    2015-08-01

    Solenopsis invicta Buren is an important invasive pest that has a negative impact on biodiversity. However, current knowledge regarding the ecological effects of its interaction with honeydew-producing hemipteran insects is inadequate. To partially address this problem, we assessed whether the interaction between the two invasive species S. invicta and Phenacoccus solenopsis Tinsley mediated predation of P. solenopsis by Propylaea japonica Thunbery lady beetles using field investigations and indoor experiments. S. invicta tending significantly reduced predation by the Pr. japonica lady beetle, and this response was more pronounced for lady beetle larvae than for adults. A field investigation showed that the species richness and quantity of lady beetle species in plots with fire ants were much lower than in those without fire ants. In an olfaction bioassay, lady beetles preferred to move toward untended rather than tended mealybugs. Overall, these results suggest that mutualism between S. invicta and P. solenopsis may have a serious impact on predation of P. solenopsis by lady beetles, which could promote growth of P. solenopsis populations.

  7. Comparing fungal band formulations for Asian longhorned beetle biological control.

    PubMed

    Ugine, Todd A; Jenkins, Nina E; Gardescu, Sana; Hajek, Ann E

    2013-07-01

    Experiments were conducted with the fungal entomopathogen Metarhizium brunneum to determine the feasibility of using agar-based fungal bands versus two new types of oil-formulated fungal bands for Asian longhorned beetle management. We investigated conidial retention and survival on three types of bands attached to trees in New York and Pennsylvania: standard polyester fiber agar-based bands containing fungal cultures, and two types of bands made by soaking either polyester fiber or jute burlap with oil-conidia suspensions. Fungal band formulation did not affect the number or viability of conidia on bands over the 2-month test period, although percentage conidial viability decreased significantly with time for all band types. In a laboratory experiment testing the effect of the three band formulations on conidial acquisition and beetle survival, traditional agar-based fungal bands delivered the most conidia to adult beetles and killed higher percentages of beetles significantly faster (median survival time of 27d) than the two oil-formulated materials (36-37d). We also tested the effect of band formulation on conidial acquisition by adult beetles kept individually in cages with a single band for 24h, and significantly more conidia (3-7times) were acquired by beetles from agar-based bands compared to the two oil formulations. PMID:23628142

  8. Attractants for the green June beetle (Coleoptera: Scarabaeidae).

    PubMed

    Johnson, D T; Lewis, B A; Bryant, R J; Liyanage, R; Lay, J O; Pszczolkowski, M A

    2009-12-01

    The purpose of this study was to develop and evaluate lures for adult green June beetles, Cotinis nitida (L.) (Coleoptera: Scarabaeidae), for future use in a mass trapping program. Volatile organic compounds collected from headspace of green June beetles feeding on fermenting ripe apple (Malus spp.), the natural lure that elicits feeding aggregations, were identified and confirmed by gas chromatography and mass spectrometry. Yellow funnel traps baited with 91% isopropanol or the five component blend were equally effective in eliciting aggregation behavior and often more attractive to green June beetles than the natural lure. In 2008, three trap lines adjacent and parallel to the perimeter of two vineyards, each with 12 Xpando yellow funnel traps baited with either 91% isopropanol or the five component blend, differed in catch of green June beetles across sample dates, and sample date by bait interaction but there were no differences among these two baits. A season total of 324,007 green June beetle were captured by these 36 baited traps. A brief review is included of fermentation volatiles attractive to insects. We conclude with the potential cost to use mass trapping against adult green June beetles.

  9. First record of a Mermithidae (Nematoda) from the meloid beetle Meloe violaceus Marsham, 1802 (Coleoptera: Meloidae).

    PubMed

    Lückmann, Johannes; Poinar, George O

    2003-05-01

    A new record of nematode parasitism of meloid beetles is reported and all earlier records are summarised. Rates of parasitism could be influenced by the toxic compound cantharidin that these beetles possess.

  10. Limited transmission of the ectoparasitic fungus Hesperomyces virescens between lady beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ectoparasitic fungus Hesperomyces virescens Thaxter (Ascomycota: Laboulbeniales) commonly infects the invasive lady beetle Harmonia axyridis (Pallas) and several other aphidophagous lady beetles in North America and Europe. We tested the hypothesis that bodily contact between adults of differen...

  11. New records of predaceous diving beetles (Coleoptera:Dytiscidae) in Maine

    USGS Publications Warehouse

    Boobar, L.R.; Gibbs, K.E.; Longcore, J.R.; Perillo, A.M.

    1996-01-01

    Locations, habitat descriptions, and collection dates are listed for new records of 4 genera and 12 species of predaceous diving beetles (Coleoptera: Dytiscidae) in Maine. Previously, 17 genera and 53 species of the aquatic beetle were reported from Maine.

  12. Oviposition by small hive beetles elicits hygienic responses from Cape honeybees.

    PubMed

    Ellis, J D; Richards, C S; Hepburn, H R; Elzen, P J

    2003-11-01

    Two novel behaviours, both adaptations of small hive beetles ( Aethina tumida Murray) and Cape honeybees ( Apis mellifera capensis Esch.), are described. Beetles puncture the sides of empty cells and oviposit under the pupae in adjoining cells. However, bees detect this ruse and remove infested brood (hygienic behaviour), even under such well-disguised conditions. Indeed, bees removed 91% of treatment brood (brood cells with punctured walls caused by beetles) but only 2% of control brood (brood not exposed to beetles). Only 91% of treatment brood actually contained beetle eggs; the data therefore suggest that bees remove only that brood containing beetle eggs and leave uninfected brood alone, even if beetles have accessed (but not oviposited on) the brood. Although this unique oviposition strategy by beetles appears both elusive and adaptive, Cape honeybees are able to detect and remove virtually all of the infested brood.

  13. How-To-Do-It. A Beetle, a Bur, and the Potato: An Introduction to Ecology.

    ERIC Educational Resources Information Center

    Jantzen, Paul G.

    1983-01-01

    Describes how the interrelation of the potato beetle, the buffalo-bur, and the potato is used as an introduction to ecology. Methods of controlling the beetle and ecological principles illustrated in the interrelationship are discussed. (JN)

  14. First record of a Mermithidae (Nematoda) from the meloid beetle Meloe violaceus Marsham, 1802 (Coleoptera: Meloidae).

    PubMed

    Lückmann, Johannes; Poinar, George O

    2003-05-01

    A new record of nematode parasitism of meloid beetles is reported and all earlier records are summarised. Rates of parasitism could be influenced by the toxic compound cantharidin that these beetles possess. PMID:12743809

  15. Identification of sound-producing hydrophilid beetles in underwater recordings using digital signal processing

    NASA Astrophysics Data System (ADS)

    Rudh, Nissa E.

    For this study, a classification program capable of identifying four hydrophilid beetle species from vocalizations in under water hydrophone recordings was created. Within single-species recordings, classification accuracy ranged from 81-98%. Mathematical features, based on the frequency content of exemplar beetle vocalizations, were used to compare hydrophilid vocalizations with new sound data in Matlab(TM) and classify sounds as a beetle species, beetle distress call, or noise.

  16. Endocrine Control of Exaggerated Trait Growth in Rhinoceros Beetles.

    PubMed

    Zinna, R; Gotoh, H; Brent, C S; Dolezal, A; Kraus, A; Niimi, T; Emlen, D; Lavine, L C

    2016-08-01

    Juvenile hormone (JH) is a key insect growth regulator frequently involved in modulating phenotypically plastic traits such as caste determination in eusocial species, wing polymorphisms in aphids, and mandible size in stag beetles. The jaw morphology of stag beetles is sexually-dimorphic and condition-dependent; males have larger jaws than females and those developing under optimum conditions are larger in overall body size and have disproportionately larger jaws than males raised under poor conditions. We have previously shown that large males have higher JH titers than small males during development, and ectopic application of fenoxycarb (JH analog) to small males can induce mandibular growth similar to that of larger males. What remains unknown is whether JH regulates condition-dependent trait growth in other insects with extreme sexually selected structures. In this study, we tested the hypothesis that JH mediates the condition-dependent expression of the elaborate horns of the Asian rhinoceros beetle, Trypoxylus dichotomus. The sexually dimorphic head horn of this beetle is sensitive to nutritional state during larval development. Like stag beetles, male rhinoceros beetles receiving copious food produce disproportionately large horns for their body size compared with males under restricted diets. We show that JH titers are correlated with body size during the late feeding and early prepupal periods, but this correlation disappears by the late prepupal period, the period of maximum horn growth. While ectopic application of fenoxycarb during the third larval instar significantly delayed pupation, it had no effect on adult horn size relative to body size. Fenoxycarb application to late prepupae also had at most a marginal effect on relative horn size. We discuss our results in context of other endocrine signals of condition-dependent trait exaggeration and suggest that different beetle lineages may have co-opted different physiological signaling mechanisms to

  17. Distance and Sex Determine Host Plant Choice by Herbivorous Beetles

    PubMed Central

    Ballhorn, Daniel J.; Kautz, Stefanie; Heil, Martin

    2013-01-01

    Background Plants respond to herbivore damage with the release of volatile organic compounds (VOCs). This indirect defense can cause ecological costs when herbivores themselves use VOCs as cues to localize suitable host plants. Can VOCs reliably indicate food plant quality to herbivores? Methodology We determined the choice behavior of herbivorous beetles (Chrysomelidae: Gynandrobrotica guerreroensis and Cerotoma ruficornis) when facing lima bean plants (Fabaceae: Phaseolus lunatus) with different cyanogenic potential, which is an important constitutive direct defense. Expression of inducible indirect defenses was experimentally manipulated by jasmonic acid treatment at different concentrations. The long-distance responses of male and female beetles to the resulting induced plant volatiles were investigated in olfactometer and free-flight experiments and compared to the short-distance decisions of the same beetles in feeding trials. Conclusion Female beetles of both species were repelled by VOCs released from all induced plants independent of the level of induction. In contrast, male beetles were repelled by strongly induced plants, showed no significant differences in choice behavior towards moderately induced plants, but responded positively to VOCs released from little induced plants. Thus, beetle sex and plant VOCs had a significant effect on host searching behavior. By contrast, feeding behavior of both sexes was strongly determined by the cyanogenic potential of leaves, although females again responded more sensitively than males. Apparently, VOCs mainly provide information to these beetles that are not directly related to food quality. Being induced by herbivory and involved in indirect plant defense, such VOCs might indicate the presence of competitors and predators to herbivores. We conclude that plant quality as a food source and finding a potentially enemy-free space is more important for female than for male insect herbivores, whereas the presence of a

  18. 7 CFR 301.48-6 - Movement of live Japanese beetles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Movement of live Japanese beetles. 301.48-6 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Japanese Beetle Quarantine and Regulations § 301.48-6 Movement of live Japanese beetles. Regulations requiring a permit for and...

  19. 7 CFR 301.48-6 - Movement of live Japanese beetles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Movement of live Japanese beetles. 301.48-6 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Japanese Beetle Quarantine and Regulations § 301.48-6 Movement of live Japanese beetles. Regulations requiring a permit for and...

  20. 7 CFR 301.48-6 - Movement of live Japanese beetles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Movement of live Japanese beetles. 301.48-6 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Japanese Beetle Quarantine and Regulations § 301.48-6 Movement of live Japanese beetles. Regulations requiring a permit for and...

  1. 7 CFR 305.26 - Khapra beetle treatment schedule for feeds and milled products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Khapra beetle treatment schedule for feeds and milled... Treatments § 305.26 Khapra beetle treatment schedule for feeds and milled products. Feeds and milled products may be treated for khapra beetle using schedule T307-a. The temperature must be 180 °F in any part...

  2. 7 CFR 301.48-6 - Movement of live Japanese beetles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Movement of live Japanese beetles. 301.48-6 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Japanese Beetle Quarantine and Regulations § 301.48-6 Movement of live Japanese beetles. Regulations requiring a permit for and...

  3. 7 CFR 301.48-6 - Movement of live Japanese beetles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Movement of live Japanese beetles. 301.48-6 Section... INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE DOMESTIC QUARANTINE NOTICES Japanese Beetle Quarantine and Regulations § 301.48-6 Movement of live Japanese beetles. Regulations requiring a permit for and...

  4. Effect of crop rotation distance on populations of Colorado potato beetle (Coleoptera: Chrysomelidae): development of areawide Colorado potato beetle pest management strategies.

    PubMed

    Sexson, Deana L; Wyman, Jeffrey A

    2005-06-01

    The Colorado potato beetle, Leptinotarsa decemlineata (Say), overwinters adjacent to field edges and infests nearby fields in the spring, primarily by walking. Crop rotation is known to be an effective cultural control against Colorado potato beetle populations limiting spring infestations. Spatial separation is an important consideration in optimizing the rotational effect because long-distance rotations have been shown to reduce Colorado potato beetle infestations. To determine the effect of long-distance rotations on Colorado potato beetle populations in commercial Wisconsin potato production, a geographic area of >18,200 ha (>45,000) acres in southern Portage County, Wisconsin, was selected as an experimental area for areawide pest management of the Colorado potato beetle. From 1997 to 1999, beetle populations at edges within each potato field in this region were determined by spring and fall field sampling. The rotational distance between current and previous potato fields was measured and analysis was run between the distance and Colorado potato beetle populations. Long-distance rotations of >400 m were an effective cultural control management strategy to limit adult beetle infestations in the spring. This strategy can be optimized when collaborating growers are able to maximize their rotational distances by coordinating their rotational schemes within large areawide, geographic locations. Deploying long-distance rotations within a geographic area over many years would limit Colorado potato beetle populations and could result in a significantly reduced Colorado potato beetle populations entering fields in the spring.

  5. DNA Barcoding of Japanese Click Beetles (Coleoptera, Elateridae)

    PubMed Central

    Oba, Yuichi; Ôhira, Hitoo; Murase, Yukio; Moriyama, Akihiko; Kumazawa, Yoshinori

    2015-01-01

    Click beetles (Coleoptera: Elateridae) represent one of the largest groups of beetle insects. Some click beetles in larval form, known as wireworms, are destructive agricultural pests. Morphological identification of click beetles is generally difficult and requires taxonomic expertise. This study reports on the DNA barcoding of Japanese click beetles to enable their rapid and accurate identification. We collected and assembled 762 cytochrome oxidase subunit I barcode sequences from 275 species, which cover approximately 75% of the common species found on the Japanese main island, Honshu. This barcode library also contains 20 out of the 21 potential pest species recorded in Japan. Our analysis shows that most morphologically identified species form distinct phylogenetic clusters separated from each other by large molecular distances. This supports the general usefulness of the DNA barcoding approach for quick and reliable identification of Japanese elaterid species for environmental impact assessment, agricultural pest control, and biodiversity analysis. On the other hand, the taxonomic boundary in dozens of species did not agree with the boundary of barcode index numbers (a criterion for sequence-based species delimitation). These findings urge taxonomic reinvestigation of these mismatched taxa. PMID:25636000

  6. DNA barcoding of Japanese click beetles (Coleoptera, Elateridae).

    PubMed

    Oba, Yuichi; Ôhira, Hitoo; Murase, Yukio; Moriyama, Akihiko; Kumazawa, Yoshinori

    2015-01-01

    Click beetles (Coleoptera: Elateridae) represent one of the largest groups of beetle insects. Some click beetles in larval form, known as wireworms, are destructive agricultural pests. Morphological identification of click beetles is generally difficult and requires taxonomic expertise. This study reports on the DNA barcoding of Japanese click beetles to enable their rapid and accurate identification. We collected and assembled 762 cytochrome oxidase subunit I barcode sequences from 275 species, which cover approximately 75% of the common species found on the Japanese main island, Honshu. This barcode library also contains 20 out of the 21 potential pest species recorded in Japan. Our analysis shows that most morphologically identified species form distinct phylogenetic clusters separated from each other by large molecular distances. This supports the general usefulness of the DNA barcoding approach for quick and reliable identification of Japanese elaterid species for environmental impact assessment, agricultural pest control, and biodiversity analysis. On the other hand, the taxonomic boundary in dozens of species did not agree with the boundary of barcode index numbers (a criterion for sequence-based species delimitation). These findings urge taxonomic reinvestigation of these mismatched taxa.

  7. Origin and Diversification of Dung Beetles in Madagascar

    PubMed Central

    Miraldo, Andreia; Wirta, Helena; Hanski, Ilkka

    2011-01-01

    Madagascar has a rich fauna of dung beetles (Scarabaeinae and Aphodiinae) with almost 300 species described to date. Like most other taxa in Madagascar, dung beetles exhibit an exceptionally high level of endemism (96% of the species). Here, we review the current knowledge of the origin and diversification of Malagasy dung beetles. Based on molecular phylogenies, the extant dung beetles originate from eight colonizations, of which four have given rise to extensive radiations. These radiations have occurred in wet forests, while the few extant species in the less successful radiations occur in open and semi-open habitats. We discuss the likely mechanisms of speciation and the ecological characteristics of the extant communities, emphasizing the role of adaptation along environmental gradients and allopatric speciation in generating the exceptionally high beta diversity in Malagasy dung beetles. Phylogeographic analyses of selected species reveal complex patterns with evidence for genetic introgression between old taxa. The introduction of cattle to Madagascar 1500 years ago created a new abundant resource, onto which a few species have shifted and thereby been able to greatly expand their geographical ranges. PMID:26467617

  8. Dung beetles use the Milky Way for orientation.

    PubMed

    Dacke, Marie; Baird, Emily; Byrne, Marcus; Scholtz, Clarke H; Warrant, Eric J

    2013-02-18

    When the moon is absent from the night sky, stars remain as celestial visual cues. Nonetheless, only birds, seals, and humans are known to use stars for orientation. African ball-rolling dung beetles exploit the sun, the moon, and the celestial polarization pattern to move along straight paths, away from the intense competition at the dung pile. Even on clear moonless nights, many beetles still manage to orientate along straight paths. This led us to hypothesize that dung beetles exploit the starry sky for orientation, a feat that has, to our knowledge, never been demonstrated in an insect. Here, we show that dung beetles transport their dung balls along straight paths under a starlit sky but lose this ability under overcast conditions. In a planetarium, the beetles orientate equally well when rolling under a full starlit sky as when only the Milky Way is present. The use of this bidirectional celestial cue for orientation has been proposed for vertebrates, spiders, and insects, but never proven. This finding represents the first convincing demonstration for the use of the starry sky for orientation in insects and provides the first documented use of the Milky Way for orientation in the animal kingdom.

  9. Dung beetles use the Milky Way for orientation.

    PubMed

    Dacke, Marie; Baird, Emily; Byrne, Marcus; Scholtz, Clarke H; Warrant, Eric J

    2013-02-18

    When the moon is absent from the night sky, stars remain as celestial visual cues. Nonetheless, only birds, seals, and humans are known to use stars for orientation. African ball-rolling dung beetles exploit the sun, the moon, and the celestial polarization pattern to move along straight paths, away from the intense competition at the dung pile. Even on clear moonless nights, many beetles still manage to orientate along straight paths. This led us to hypothesize that dung beetles exploit the starry sky for orientation, a feat that has, to our knowledge, never been demonstrated in an insect. Here, we show that dung beetles transport their dung balls along straight paths under a starlit sky but lose this ability under overcast conditions. In a planetarium, the beetles orientate equally well when rolling under a full starlit sky as when only the Milky Way is present. The use of this bidirectional celestial cue for orientation has been proposed for vertebrates, spiders, and insects, but never proven. This finding represents the first convincing demonstration for the use of the starry sky for orientation in insects and provides the first documented use of the Milky Way for orientation in the animal kingdom. PMID:23352694

  10. Origin and Diversification of Dung Beetles in Madagascar.

    PubMed

    Miraldo, Andreia; Wirta, Helena; Hanski, Ilkka

    2011-04-20

    Madagascar has a rich fauna of dung beetles (Scarabaeinae and Aphodiinae) withalmost 300 species described to date. Like most other taxa in Madagascar, dung beetles exhibit an exceptionally high level of endemism (96% of the species). Here,we review the current knowledge of the origin and diversification of Malagasy dung beetles. Based on molecular phylogenies, the extant dung beetles originate from eight colonizations, of which four have given rise to extensive radiations. These radiations have occurred in wet forests, while the few extant species in the less successfulradiations occur in open and semi-open habitats. We discuss the likely mechanisms of speciation and the ecological characteristics of the extant communities, emphasizing the role of adaptation along environmental gradients and allopatric speciation in generating the exceptionally high beta diversity in Malagasy dung beetles. Phylogeographic analyses of selected species reveal complex patterns with evidence for genetic introgression between old taxa. The introduction of cattle to Madagascar 1500 years ago created a new abundant resource, onto which a few species haveshifted and thereby been able to greatly expand their geographical ranges.

  11. Multivariate intralocus sexual conflict in seed beetles.

    PubMed

    Berger, David; Berg, Elena C; Widegren, William; Arnqvist, Göran; Maklakov, Alexei A

    2014-12-01

    Intralocus sexual conflict (IaSC) is pervasive because males and females experience differences in selection but share much of the same genome. Traits with integrated genetic architecture should be reservoirs of sexually antagonistic genetic variation for fitness, but explorations of multivariate IaSC are scarce. Previously, we showed that upward artificial selection on male life span decreased male fitness but increased female fitness compared with downward selection in the seed beetle Callosobruchus maculatus. Here, we use these selection lines to investigate sex-specific evolution of four functionally integrated traits (metabolic rate, locomotor activity, body mass, and life span) that collectively define a sexually dimorphic life-history syndrome in many species. Male-limited selection for short life span led to correlated evolution in females toward a more male-like multivariate phenotype. Conversely, males selected for long life span became more female-like, implying that IaSC results from genetic integration of this suite of traits. However, while life span, metabolism, and body mass showed correlated evolution in the sexes, activity did not evolve in males but, surprisingly, did so in females. This led to sexual monomorphism in locomotor activity in short-life lines associated with detrimental effects in females. Our results thus support the general tenet that widespread pleiotropy generates IaSC despite sex-specific genetic architecture.

  12. Structural color in beetles of South America

    NASA Astrophysics Data System (ADS)

    Luna, Ana E.; Skigin, Diana C.; Inchaussandague, Marina E.; Roig Alsina, Arturo

    2010-08-01

    Photonic microstructures in nature, specifically in endemic species of Coleoptera from Argentina and the south of Chile have been identified, analyzed and modeled. These natural systems produce partial photonic bandgaps (PBGs) as a result of the high periodicity of the microstructures found in some parts of their bodies. With the aid of scanning (SEM) and transmission (TEM) electron microscopy we have identified that the elytron (modified forewing of a beetle that encases the thin hind wings used in flight) of these insects shows a periodic structure which originates diffractive phenomena resulting in extraordinary physical effects such as iridescent or metallic colors. We measured the reflectance spectrum and obtained the chromaticity diagrams of the samples with an Ocean Optics 4000 spectrophotometer. The geometrical parameters of the structure were obtained by processing the SEM images with the ImageJ software, to introduce them in our electromagnetic model. In all cases, a satisfactory agreement between the measurements and the numerical results was obtained. This permits us to explain the mechanism of color production in those specimens. The study of structural colors in the natural world can inspire the development of artificial devices with particular applications in technology, such as intelligent sensors and new kinds of filters.

  13. Hold your breath beetle-Mites!

    PubMed

    Gudowska, Agnieszka; Drobniak, Szymon M; Schramm, Bartosz W; Labecka, Anna Maria; Kozlowski, Jan; Bauchinger, Ulf

    2016-01-01

    Respiratory gas exchange in insects occurs via a branching tracheal system. The entrances to the air-filled tracheae are the spiracles, which are gate-like structures in the exoskeleton. The open or closed state of spiracles defines the three possible gas exchange patterns of insects. In resting insects, spiracles may open and close over time in a repeatable fashion that results in a discontinuous gas exchange (DGE) pattern characterized by periods of zero organism-to-environment gas exchange. Several adaptive hypotheses have been proposed to explain why insects engage in DGE, but none have attracted overwhelming support. We provide support for a previously untested hypothesis that posits that DGE minimizes the risk of infestation of the tracheal system by mites and other agents. Here, we analyze the respiratory patterns of 15 species of ground beetle (Carabidae), of which more than 40% of individuals harbored external mites. Compared with mite-free individuals, infested one's engaged significantly more often in DGE. Mite-free individuals predominantly employed a cyclic or continuous gas exchange pattern, which did not include complete spiracle closure. Complete spiracle closure may prevent parasites from invading, clogging, or transferring pathogens to the tracheal system or from foraging on tissue not protected by thick chitinous layers.

  14. Polycarboxylates Enhance Beetle Antifreeze Protein Activity

    PubMed Central

    Amornwittawat, Natapol; Wang, Sen; Duman, John G.; Wen, Xin

    2008-01-01

    Summary Antifreeze proteins (AFPs) lower the noncolligative freezing point of water in the presence of ice below the ice melting point. The temperature difference between the melting point and the noncolligative freezing point is termed thermal hysteresis (TH). The magnitude of the TH depends on the specific activity and the concentration of AFP, and the concentration of enhancers in the solution. Known enhancers are certain low molecular mass molecules and proteins. Here, we investigated a series of polycarboxylates that enhance the TH activity of an AFP from the beetle Dendroides canadensis (DAFP) using differential scanning calorimetry (DSC). Triethylenetetramine-N,N,N′,N″,N‴,N‴-hexaacetate, the most efficient enhancer identified in this work, can increase the TH of DAFP by nearly 1.5 fold over than that of the published best enhancer, citrate. The Zn2+ coordinated carboxylate results in loss of the enhancement ability of the carboxylate on antifreeze activity. There is not an additional increase in TH when a weaker enhancer is added to a stronger enhancer solution. These observations suggest that the more carboxylate groups per enhancer molecule the better the efficiency of the enhancer and that the freedom of motion of these molecules is necessary for them to serve as enhancers for AFP. The hydroxyl groups in the enhancer molecules can also positively affect their TH enhancement efficiency, though not as strongly as carboxylate groups. Mechanisms are discussed. PMID:18620083

  15. Can rove beetles (Staphylinidae) be excluded in studies focusing on saproxylic beetles in central European beech forests?

    PubMed

    Parmain, G; Bouget, C; Müller, J; Horak, J; Gossner, M M; Lachat, T; Isacsson, G

    2015-02-01

    Monitoring saproxylic beetle diversity, though challenging, can help identifying relevant conservation sites or key drivers of forest biodiversity, and assessing the impact of forestry practices on biodiversity. Unfortunately, monitoring species assemblages is costly, mainly due to the time spent on identification. Excluding families which are rich in specimens and species but are difficult to identify is a frequent procedure used in ecological entomology to reduce the identification cost. The Staphylinidae (rove beetle) family is both one of the most frequently excluded and one of the most species-rich saproxylic beetle families. Using a large-scale beetle and environmental dataset from 238 beech stands across Europe, we evaluated the effects of staphylinid exclusion on results in ecological forest studies. Simplified staphylinid-excluded assemblages were found to be relevant surrogates for whole assemblages. The species richness and composition of saproxylic beetle assemblages both with and without staphylinids responded congruently to landscape, climatic and stand gradients, even when the assemblages included a high proportion of staphylinid species. At both local and regional scales, the species richness as well as the species composition of staphylinid-included and staphylinid-excluded assemblages were highly positively correlated. Ranking of sites according to their biodiversity level, which either included or excluded Staphylinidae in species richness, also gave congruent results. From our results, species assemblages omitting staphylinids can be taken as efficient surrogates for complete assemblages in large scale biodiversity monitoring studies.

  16. Arsenic accumulation in bark beetles and forest birds occupying mountain pine beetle infested stands treated with monosodium methanearsonate.

    PubMed

    Morrissey, Christy A; Albert, Courtney A; Dods, Patti L; Cullen, William R; Lai, Vivian W M; Elliott, John E

    2007-02-15

    The arsenic-based pesticide, monosodium methanearsonate (MSMA), is presently being evaluated for re-registration in Canada and the United States and has been widely used in British Columbia to help suppress Mountain Pine Beetle (MPB) outbreaks. We assessed the availability and exposure of MSMA to woodpeckers and other forest birds that may prey directly on contaminated bark beetles. Total arsenic residues in MPB from MSMA treated trees ranged from 1.3-700.2 microg g(-1) dw (geometric mean 42.0 microg g(-1)) with the metabolite monomethyl arsonic acid (MMAA) contributing 90-97% to the total arsenic extracted. Live adult and larval beetles were collected from treated trees and reached concentrations up to 327 microg g(-1) dw. MPBs from reference trees had significantly lower arsenic concentrations averaging 0.19 microg g(-1) dw. Woodpeckers foraged more heavily on MSMAtreesthat contained beetles with lower arsenic residues, suggesting those trees had reduced MSMAtranslocation and possibly greater live beetle broods. Blood samples from five species of woodpeckers and other forest passerines breeding within 1 km of MSMA stands contained elevated levels of total arsenic but with large individual variability (geometric mean = 0.18 microg g(-1) dw, range 0.02-2.20 microg g(-1). The results indicate that there is significant accumulation and transfer of organic arsenic within the food chain at levels that may present a toxicity risk to avian wildlife.

  17. [The succession of sarcophagus beetles on carrion and its application in forensic medicine].

    PubMed

    Peng, Qian-Yi; Ye, Lu-Si; Ma, Li-Ping; Cai, Ji-Feng

    2009-12-01

    Sarcophagus beetles, which can not be replaced by Diptera, play a pivotal role not only in estimating PMI of dry human skeletal remains in the later stages decomposition of carcasses, but also the corruption, destruction, decomposition and posture changes of carcasses. This article explicates the succession of sarcophagus beetles on carrion and its influencing factors, and introduces the application and prospects of sarcophagus beetles in forensic entomology. Although few researches focus on sarcophagus beetles at present, it is believed that more and more forensic scientists will pay attention to sarcophagus beetles' application in forensic identification.

  18. Optimal foraging for specific nutrients in predatory beetles

    PubMed Central

    Jensen, Kim; Mayntz, David; Toft, Søren; Clissold, Fiona J.; Hunt, John; Raubenheimer, David; Simpson, Stephen J.

    2012-01-01

    Evolutionary theory predicts that animals should forage to maximize their fitness, which in predators is traditionally assumed equivalent to maximizing energy intake rather than balancing the intake of specific nutrients. We restricted female predatory ground beetles (Anchomenus dorsalis) to one of a range of diets varying in lipid and protein content, and showed that total egg production peaked at a target intake of both nutrients. Other beetles given a choice to feed from two diets differing only in protein and lipid composition selectively ingested nutrient combinations at this target intake. When restricted to nutritionally imbalanced diets, beetles balanced the over- and under-ingestion of lipid and protein around a nutrient composition that maximized egg production under those constrained circumstances. Selective foraging for specific nutrients in this predator thus maximizes its reproductive performance. Our findings have implications for predator foraging behaviour and in the structuring of ecological communities. PMID:22237910

  19. The alternative Pharaoh approach: stingless bees mummify beetle parasites alive

    NASA Astrophysics Data System (ADS)

    Greco, Mark K.; Hoffmann, Dorothee; Dollin, Anne; Duncan, Michael; Spooner-Hart, Robert; Neumann, Peter

    2010-03-01

    Workers from social insect colonies use different defence strategies to combat invaders. Nevertheless, some parasitic species are able to bypass colony defences. In particular, some beetle nest invaders cannot be killed or removed by workers of social bees, thus creating the need for alternative social defence strategies to ensure colony survival. Here we show, using diagnostic radioentomology, that stingless bee workers ( Trigona carbonaria) immediately mummify invading adult small hive beetles ( Aethina tumida) alive by coating them with a mixture of resin, wax and mud, thereby preventing severe damage to the colony. In sharp contrast to the responses of honeybee and bumblebee colonies, the rapid live mummification strategy of T. carbonaria effectively prevents beetle advancements and removes their ability to reproduce. The convergent evolution of mummification in stingless bees and encapsulation in honeybees is another striking example of co-evolution between insect societies and their parasites.

  20. The alternative Pharaoh approach: stingless bees mummify beetle parasites alive.

    PubMed

    Greco, Mark K; Hoffmann, Dorothee; Dollin, Anne; Duncan, Michael; Spooner-Hart, Robert; Neumann, Peter

    2010-03-01

    Workers from social insect colonies use different defence strategies to combat invaders. Nevertheless, some parasitic species are able to bypass colony defences. In particular, some beetle nest invaders cannot be killed or removed by workers of social bees, thus creating the need for alternative social defence strategies to ensure colony survival. Here we show, using diagnostic radioentomology, that stingless bee workers (Trigona carbonaria) immediately mummify invading adult small hive beetles (Aethina tumida) alive by coating them with a mixture of resin, wax and mud, thereby preventing severe damage to the colony. In sharp contrast to the responses of honeybee and bumblebee colonies, the rapid live mummification strategy of T. carbonaria effectively prevents beetle advancements and removes their ability to reproduce. The convergent evolution of mummification in stingless bees and encapsulation in honeybees is another striking example of co-evolution between insect societies and their parasites.

  1. Chemical defense of a rove beetle (Creophilus maxillosus).

    PubMed

    Jefson, M; Meinwald, J; Nowicki, S; Hicks, K; Eisner, T

    1983-01-01

    The abdominal defensive glands ofC. maxillosus secrete a mixture (70μg/beetle) of isoamyl alcohol (I), isoamyl acetate (II), iridodial (III), actinidine (IV), dihydronepetalactone (VE), and (E)-8-oxocitronellyl acetate (X). When disturbed, the beetle everts the glands and revolves the abdomen so as to wipe the glands against the offending agent. Fecal fluid is commonly emitted at the same time and may become added to the glandular material. Ants (Formica exsectoides) are effectively fended off by the beetle and were shown in bioassays (Monomorium destructor) to be repelled by the four major components of the secretion (II, III, X, VE); the principal component (VE) was the most active. Some anatomical features of the glands are described.

  2. Dual-color click beetle luciferase heteroprotein fragment complementation assays.

    PubMed

    Villalobos, Victor; Naik, Snehal; Bruinsma, Monique; Dothager, Robin S; Pan, Mei-Hsiu; Samrakandi, Mustapha; Moss, Britney; Elhammali, Adnan; Piwnica-Worms, David

    2010-09-24

    Understanding the functional complexity of protein interactions requires mapping biomolecular complexes within the cellular environment over biologically relevant time scales. Herein, we describe a set of reversible multicolored heteroprotein complementation fragments based on various firefly and click beetle luciferases that utilize the same substrate, D-luciferin. Luciferase heteroprotein fragment complementation systems enabled dual-color quantification of two discrete pairs of interacting proteins simultaneously or two distinct proteins interacting with a third shared protein in live cells. Using real-time analysis of click beetle green and click beetle red luciferase heteroprotein fragment complementation applied to β-TrCP, an E3-ligase common to the regulation of both β-catenin and IκBα, GSK3β was identified as a candidate kinase regulating IκBα processing. These dual-color protein interaction switches may enable directed dynamic analysis of a variety of protein interactions in living cells.

  3. Susceptibility of the Adult Japanese Beetle, Popillia japonica to Entomopathogenic Nematodes.

    PubMed

    Morris, E Erin; Grewal, Parwinder S

    2011-09-01

    To build upon prior research demonstrating the potential of entomopathogenic nematode dissemination by infected adult Japanese beetle, Popillia japonica, we evaluated susceptibility of the adult beetles to 20 strains of Steinernema and Heterorhabditis under laboratory conditions. The nematodes were applied at a rate of 10,000 infective juveniles per 10 adult beetles in 148 mL plastic cups containing autoclaved sand and sassafras leaves as a source of food for the beetles. All strains infected the beetles and caused 55% to 95% mortality. The most virulent strains that caused 50% beetle mortality in less than 5 days included a strain of H. georgiana (D61), three strains of Steinernema sp. (R54, R45, and FC48), and two strains of S. carpocapsae (All and D60). The ability of two strains of Steinernema sp. (R45 and R54) and two strains of Heterorhabditis bacteriophora (D98 and GPS11) to infect and reproduce in the beetle was further examined to assess the potential of infected beetles to disseminate nematodes upon their death. All four strains infected and killed the beetles, but only Steinernema strains reproduced in the cadavers. We conclude that both Heterorhabditis and Steinernema strains are able to cause mortality to adult Japanese beetle, but Steinernema strains may be effectively disseminated due to their reproduction in the beetle.

  4. Susceptibility of the Adult Japanese Beetle, Popillia japonica to Entomopathogenic Nematodes

    PubMed Central

    Morris, E. Erin; Grewal, Parwinder S.

    2011-01-01

    To build upon prior research demonstrating the potential of entomopathogenic nematode dissemination by infected adult Japanese beetle, Popillia japonica, we evaluated susceptibility of the adult beetles to 20 strains of Steinernema and Heterorhabditis under laboratory conditions. The nematodes were applied at a rate of 10,000 infective juveniles per 10 adult beetles in 148 mL plastic cups containing autoclaved sand and sassafras leaves as a source of food for the beetles. All strains infected the beetles and caused 55% to 95% mortality. The most virulent strains that caused 50% beetle mortality in less than 5 days included a strain of H. georgiana (D61), three strains of Steinernema sp. (R54, R45, and FC48), and two strains of S. carpocapsae (All and D60). The ability of two strains of Steinernema sp. (R45 and R54) and two strains of Heterorhabditis bacteriophora (D98 and GPS11) to infect and reproduce in the beetle was further examined to assess the potential of infected beetles to disseminate nematodes upon their death. All four strains infected and killed the beetles, but only Steinernema strains reproduced in the cadavers. We conclude that both Heterorhabditis and Steinernema strains are able to cause mortality to adult Japanese beetle, but Steinernema strains may be effectively disseminated due to their reproduction in the beetle. PMID:23431080

  5. Intercrop movement of convergent lady beetle, Hippodamia convergens (Coleoptera: Coccinellidae), between adjacent cotton and alfalfa.

    PubMed

    Bastola, Anup; Parajulee, Megha N; Porter, R Patrick; Shrestha, Ram B; Chen, Fa-Jun; Carroll, Stanley C

    2016-02-01

    A 2-year study was conducted to characterize the intercrop movement of convergent lady beetle, Hippodamia convergens Guerin-Meneville (Coleoptera: Coccinellidae) between adjacent cotton and alfalfa. A dual protein-marking method was used to assess the intercrop movement of the lady beetles in each crop. In turns field collected lady beetles in each crop were assayed by protein specific ELISA to quantify the movement of beetles between the crops. Results indicated that a high percentage of convergent lady beetles caught in cotton (46% in 2008; 56% in 2009) and alfalfa (46% in 2008; 71% in 2009) contained a protein mark, thus indicating that convergent lady beetle movement was largely bidirectional between the adjacent crops. Although at a much lower proportion, lady beetles also showed unidirectional movement from cotton to alfalfa (5% in 2008 and 6% in 2009) and from alfalfa to cotton (9% in 2008 and 14% in 2009). The season-long bidirectional movement exhibited by the beetles was significantly higher in alfalfa than cotton during both years of the study. The total influx of lady beetles (bidirectional and unidirectional combined) was significantly higher in alfalfa compared with that in cotton for both years. While convergent lady beetles moved between adjacent cotton and alfalfa, they were more attracted to alfalfa when cotton was not flowering and/or when alfalfa offered more opportunities for prey. This study offers much needed information on intercrop movement of the convergent lady beetle that should facilitate integrated pest management decisions in cotton utilizing conservation biological control.

  6. A checklist of longhorn beetles (Coleoptera: Cerambycidae) of Serbia.

    PubMed

    Ilić, Nastas; Ćurčić, Srećko

    2015-09-30

    A checklist of all taxa of the family Cerambycidae (longhorn beetles) from Serbia is presented. The checklist is based on compilation of data gathered both from authors and available literature published up to now. A total of 265 species and 92 subspecies belonging to 109 genera, 48 tribes, and six subfamilies are recorded for Serbia. However, the presence of 28 species listed in Serbia may be questionable. Known distribution and biology of Serbian taxa are provided. The diversity of the fauna of longhorn beetles in Serbia is compared with the surrounding areas in the Balkan Peninsula.

  7. Patterns of functional enzyme activity in fungus farming ambrosia beetles

    PubMed Central

    2012-01-01

    Introduction In wood-dwelling fungus-farming weevils, the so-called ambrosia beetles (Curculionidae: Scolytinae and Platypodinae), wood in the excavated tunnels is used as a medium for cultivating fungi by the combined action of digging larvae (which create more space for the fungi to grow) and of adults sowing and pruning the fungus. The beetles are obligately dependent on the fungus that provides essential vitamins, amino acids and sterols. However, to what extent microbial enzymes support fungus farming in ambrosia beetles is unknown. Here we measure (i) 13 plant cell-wall degrading enzymes in the fungus garden microbial consortium of the ambrosia beetle Xyleborinus saxesenii, including its primary fungal symbionts, in three compartments of laboratory maintained nests, at different time points after gallery foundation and (ii) four specific enzymes that may be either insect or microbially derived in X. saxesenii adult and larval individuals. Results We discovered that the activity of cellulases in ambrosia fungus gardens is relatively small compared to the activities of other cellulolytic enzymes. Enzyme activity in all compartments of the garden was mainly directed towards hemicellulose carbohydrates such as xylan, glucomannan and callose. Hemicellulolytic enzyme activity within the brood chamber increased with gallery age, whereas irrespective of the age of the gallery, the highest overall enzyme activity were detected in the gallery dump material expelled by the beetles. Interestingly endo-β-1,3(4)-glucanase activity capable of callose degradation was identified in whole-body extracts of both larvae and adult X. saxesenii, whereas endo-β-1,4-xylanase activity was exclusively detected in larvae. Conclusion Similar to closely related fungi associated with bark beetles in phloem, the microbial symbionts of ambrosia beetles hardly degrade cellulose. Instead, their enzyme activity is directed mainly towards comparatively more easily accessible hemicellulose

  8. Antimicrobial strategies in burying beetles breeding on carrion.

    PubMed

    Rozen, D E; Engelmoer, D J P; Smiseth, P T

    2008-11-18

    Rich and ephemeral resources, such as carrion, are a source of intense interspecific competition among animal scavengers and microbial decomposers. Janzen [Janzen DH (1977) Am Nat 111:691-713] hypothesized that microbes should be selected to defend such resources by rendering them unpalatable or toxic to animals, and that animals should evolve counterstrategies of avoidance or detoxification. Despite the ubiquity of animal-microbe competition, there are few tests of Janzen's hypothesis, in particular with respect to antimicrobial strategies in animals. Here, we use the burying beetle Nicrophorus vespilloides, a species that obligately breeds on carcasses of small vertebrates, to investigate the role of parental care and avoidance as antimicrobial strategies. We manipulated competition between beetle larvae and microbes by providing beetles with either fresh carcasses or old ones that had reached advanced putrefaction. We found evidence for a strong detrimental effect of microbial competition on beetle reproductive success and larval growth. We also found that parental care can largely compensate for these negative effects, and that when given a choice between old and fresh carcasses, parents tended to choose to rear their broods on the latter. We conclude that parental care and carcass avoidance can function as antimicrobial strategies in this species. Our findings extend the range of behavioral counterstrategies used by animals during competition with microbes, and generalize the work of Janzen to include competition between microbes and insects that rely on carrion as an obligate resource for breeding and not just as an opportunistic meal.

  9. Efficacy of aerosols for managing the red flour beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pest management professionals commonly utilize aerosolized liquid applications, also known as fogging, for management of stored-product insects, including the red flour beetle. These applications are part of a potential methyl bromide replacement technology because they could increase the time inte...

  10. A deficiency of the homeotic complex of the beetle Tribolium

    NASA Technical Reports Server (NTRS)

    Stuart, J. J.; Brown, S. J.; Beeman, R. W.; Denell, R. E.; Spooner, B. S. (Principal Investigator)

    1991-01-01

    In Drosophila, the establishment of regional commitments along most of the anterior/posterior axis of the developing embryo depends on two clusters of homeotic genes: the Antennapedia complex (ANT-C) and the bithorax complex (BX-C). The red flour beetle has a single complex (HOM-C) representing the homologues of the ANT-C and BX-C in juxtaposition. Beetles trans-heterozygous for two particular HOM-C mutations spontaneously generate a large deficiency, presumably by an exchange within the common region of two overlapping inversions. Genetic and molecular results indicate that this deficiency spans at least the interval between the Deformed and abdominal-A homologues. In deficiency homozygous embryos, all gnathal, thoracic and abdominal segments develop antennal appendages, suggesting that a gene(s) has been deleted that acts to distinguish trunk from head. There is no evidence that beetles have a homologue of the segmentation gene fushi tarazu of similar genomic location and function. On the basis of the genetic tractability, convenient genome size and organization of Tribolium, and its relatively long phylogenetic divergence from Drosophila (>300 million years), we have integrated developmental genetic and molecular analyses of the HOM-C. We isolated about 70 mutations in the complex representing at least six complementation groups. The homeotic phenotypes of adults and lethal embryos lead us to believe that these beetle genes are homologous with the Drosophila genes indicated in Fig. 1 (see text).

  11. Cantharimide dimers from the Chinese blister beetle, Mylabris phalerate PALLAS.

    PubMed

    Nakatani, Takafumi; Jinpo, Katsuaki; Noda, Naoki

    2007-01-01

    Five cantharidin-related compounds were isolated from the Chinese blister beetle, Mylabris phalerate PALLAS (Meloidae). Their structures were determined based on spectroscopic and chemical evidence. Three of them were identified as cantharimide dimers, which consist of two units of cantharimide combined with a tri-, tetra-, or penta-methylene group.

  12. Down and Dirty with Dung Beetles: Innovating Teaching and Research

    ERIC Educational Resources Information Center

    Kelk, Joee

    2009-01-01

    A lecturer at the University of Queensland has developed an excellent model to give students an authentic, hands-on experience of ecological research. The first-year university students have been learning about biodiversity as they carry out the task of beetle identification. This partnership gives the students a chance to contribute to an…

  13. Research on ambrosia beetles informs prevention and management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ambrosia beetles are increasingly prominent pests of trees in the U.S. Most species, particularly native, are harmless, but some exotic species are detrimental to nurseries, forest, and stored timber. Managing them remains challenging. However, it is not all doom and gloom. The increasing resear...

  14. Checklist of the Iranian Ground Beetles (Coleoptera; Carabidae).

    PubMed

    Azadbakhsh, Saeed; Nozari, Jamasb

    2015-09-30

    An up-to-date checklist of the ground beetles of Iran is presented. Altogether 955 species and subspecies in 155 genera belonging to 26 subfamilies of Carabidae are reported; 25 taxa are recorded for Iran for the fist time. New localities are listed and some previous distributional records are discussed.

  15. Use of larder beetles (Coleoptera: Dermestidae) to deflesh human jaws.

    PubMed

    Charabidze, D; Colard, T; Becart, A; Hedouin, V

    2014-01-01

    We describe new experimental data for the defleshing of human bones using larder beetles (Dermestes haemorrhoidalis) (Küster, 1852). Although the ability of larder beetles to feed on vertebrate remains has been, and still is, used by taxidermists to deflesh skulls and bones, this method has never been documented from a quantitative perspective and has over time become ignored in most forensic anthropology or odontology laboratories. To promote the rational and efficient use of this method, we performed experiments to estimate the quantity of food consumed by larvae. From the 2nd instar to nymphosis, each larva consumed a mean of 0.13±0.03 g of dry beef muscle. We then used 100±50 D. haemorrhoidalis adults and 100±50 larvae to deflesh human maxillae and mandibles sampled within a forensic context (victim identification). Each sample was weighed and photographed before, during and after the experiment. According to our experiments, 20-25 days were sufficient to completely deflesh all of the samples. We concluded that a small number of larder beetles can be used to efficiently deflesh human jaws. According to this result, the use of larder beetles appears to be an inexpensive, simple and efficient way to clean mandibles and maxillae. Furthermore, this method is DNA-safe (compared to usual maceration techniques) and thus allows the samples to be used for subsequent DNA and drug analyses.

  16. Elytra boost lift, but reduce aerodynamic efficiency in flying beetles.

    PubMed

    Johansson, L Christoffer; Engel, Sophia; Baird, Emily; Dacke, Marie; Muijres, Florian T; Hedenström, Anders

    2012-10-01

    Flying insects typically possess two pairs of wings. In beetles, the front pair has evolved into short, hardened structures, the elytra, which protect the second pair of wings and the abdomen. This allows beetles to exploit habitats that would otherwise cause damage to the wings and body. Many beetles fly with the elytra extended, suggesting that they influence aerodynamic performance, but little is known about their role in flight. Using quantitative measurements of the beetle's wake, we show that the presence of the elytra increases vertical force production by approximately 40 per cent, indicating that they contribute to weight support. The wing-elytra combination creates a complex wake compared with previously studied animal wakes. At mid-downstroke, multiple vortices are visible behind each wing. These include a wingtip and an elytron vortex with the same sense of rotation, a body vortex and an additional vortex of the opposite sense of rotation. This latter vortex reflects a negative interaction between the wing and the elytron, resulting in a single wing span efficiency of approximately 0.77 at mid downstroke. This is lower than that found in birds and bats, suggesting that the extra weight support of the elytra comes at the price of reduced efficiency. PMID:22593097

  17. "Sea Turtles" and "Ground Beetles" [Land Turtles] Should Shake Hands

    ERIC Educational Resources Information Center

    Kan, Da

    2004-01-01

    This article talks about those who come back to China after studies abroad, characterized as "sea turtles" and those scholars who have remained in China to arduously pursue their studies, characterized as "ground beetles". " Sea turtles" are those foreign MBAs and Ph.D.s who are objects of praise, admiration and are naturally more eye-catching…

  18. Faunistics of tiger beetles (Coleoptera: Cicindelidae) from Pakistan.

    PubMed

    Rafi, Muhammad Ather; Jürgen, Wiesner; Matin, Muhammad Abdul; Zia, Ahmed; Sultan, Amir; Naz, Falak

    2010-01-01

    The present biogeographic distribution of tiger beetle fauna is an attempt to register all modern taxa from Pakistan. It includes 55 taxa under 14 genera and 11 subgenera. Three species, Cylindera (Eriodera) albopunctata (Chaudoir 1852), Cicindela viridilabris (Chaudoir 1852) and Neocollyris (Neocollyris) redtenbacheri (Horn 1894) are recorded from Pakistan for the first time.

  19. Elytra boost lift, but reduce aerodynamic efficiency in flying beetles

    PubMed Central

    Johansson, L. Christoffer; Engel, Sophia; Baird, Emily; Dacke, Marie; Muijres, Florian T.; Hedenström, Anders

    2012-01-01

    Flying insects typically possess two pairs of wings. In beetles, the front pair has evolved into short, hardened structures, the elytra, which protect the second pair of wings and the abdomen. This allows beetles to exploit habitats that would otherwise cause damage to the wings and body. Many beetles fly with the elytra extended, suggesting that they influence aerodynamic performance, but little is known about their role in flight. Using quantitative measurements of the beetle's wake, we show that the presence of the elytra increases vertical force production by approximately 40 per cent, indicating that they contribute to weight support. The wing-elytra combination creates a complex wake compared with previously studied animal wakes. At mid-downstroke, multiple vortices are visible behind each wing. These include a wingtip and an elytron vortex with the same sense of rotation, a body vortex and an additional vortex of the opposite sense of rotation. This latter vortex reflects a negative interaction between the wing and the elytron, resulting in a single wing span efficiency of approximately 0.77 at mid downstroke. This is lower than that found in birds and bats, suggesting that the extra weight support of the elytra comes at the price of reduced efficiency. PMID:22593097

  20. Faunistics of Tiger Beetles (Coleoptera: Cicindelidae) from Pakistan

    PubMed Central

    Rafi, Muhammad Ather; Jürgen, Wiesner; Matin, Muhammad Abdul; Zia, Ahmed; Sultan, Amir; Naz, Falak

    2010-01-01

    The present biogeographic distribution of tiger beetle fauna is an attempt to register all modern taxa from Pakistan. It includes 55 taxa under 14 genera and 11 subgenera. Three species, Cylindera (Eriodera) albopunctata (Chaudoir 1852), Cicindela viridilabris (Chaudoir 1852) and Neocollyris (Neocollyris) redtenbacheri (Horn 1894) are recorded from Pakistan for the first time. PMID:20874597

  1. Cost of flight and the evolution of stag beetle weaponry.

    PubMed

    Goyens, Jana; Van Wassenbergh, Sam; Dirckx, Joris; Aerts, Peter

    2015-05-01

    Male stag beetles have evolved extremely large mandibles in a wide range of extraordinary shapes. These mandibles function as weaponry in pugnacious fights for females. The robust mandibles of Cyclommatus metallifer are as long as their own body and their enlarged head houses massive, hypertrophied musculature. Owing to this disproportional weaponry, trade-offs exist with terrestrial locomotion: running is unstable and approximately 40% more costly. Therefore, flying is most probably essential to cover larger distances towards females and nesting sites. We hypothesized that weight, size and shape of the weaponry will affect flight performance. Our computational fluid dynamics simulations of steady-state models (without membrane wings) reveal that male stag beetles must deliver 26% more mechanical work to fly with their heavy weaponry. This extra work is almost entirely required to carry the additional weight of the massive armature. The size and shape of the mandibles have only negligible influence on flight performance (less than 0.1%). This indicates that the evolution of stag beetle weaponry is constrained by its excessive weight, not by the size or shape of the mandibles and head as such. This most probably paved the way for the wide diversity of extraordinary mandible morphologies that characterize the stag beetle family.

  2. The Pied Piper: A Parasitic Beetle's Melodies Modulate Ant Behaviours.

    PubMed

    Di Giulio, Andrea; Maurizi, Emanuela; Barbero, Francesca; Sala, Marco; Fattorini, Simone; Balletto, Emilio; Bonelli, Simona

    2015-01-01

    Ants use various communication channels to regulate their social organisation. The main channel that drives almost all the ants' activities and behaviours is the chemical one, but it is long acknowledged that the acoustic channel also plays an important role. However, very little is known regarding exploitation of the acoustical channel by myrmecophile parasites to infiltrate the ant society. Among social parasites, the ant nest beetles (Paussus) are obligate myrmecophiles able to move throughout the colony at will and prey on the ants, surprisingly never eliciting aggression from the colonies. It has been recently postulated that stridulatory organs in Paussus might be evolved as an acoustic mechanism to interact with ants. Here, we survey the role of acoustic signals employed in the Paussus beetle-Pheidole ant system. Ants parasitised by Paussus beetles produce caste-specific stridulations. We found that Paussus can "speak" three different "languages", each similar to sounds produced by different ant castes (workers, soldiers, queen). Playback experiments were used to test how host ants respond to the sounds emitted by Paussus. Our data suggest that, by mimicking the stridulations of the queen, Paussus is able to dupe the workers of its host and to be treated as royalty. This is the first report of acoustic mimicry in a beetle parasite of ants. PMID:26154266

  3. Glycoalkaloid responses of potato to Colorado potato beetle defoliation.

    PubMed

    Pariera Dinkins, Courtney L; Peterson, Robert K D; Gibson, James E; Hu, Qing; Weaver, David K

    2008-08-01

    Two experiments were conducted to measure the glycoalkaloid concentrations of potato tubers in response to Colorado potato beetle and manual defoliation. For plants defoliated by Colorado potato beetles, there was a significantly greater production of glycoalkaloids than in control plants and manually defoliated plants for both skin and inner tissue of tubers in experiment 1. In experiment 1, there was a 58.1% and 48.3% increase in glycoalkaloids in skin and inner tissue of tubers, respectively, from plants defoliated at high levels by Colorado potato beetles compared to control plants. In experiment 2, although a significant difference in glycoalkaloid concentration was not observed among the treatments, the skin and inner tissue of tubers from plants defoliated at high levels by Colorado potato beetles increased glycoalkaloid concentration by 23.4% and 14.5%, respectively, compared to tubers from control plants. In experiment 1, the concentration of tuber extract required to reduce Chinese hamster ovary (CHO) cellular proliferation by 50% was 10-fold less for the skin versus the inner tissue, indicating that skin tissue was more toxic under the in vitro conditions of this assay.

  4. Cost of flight and the evolution of stag beetle weaponry

    PubMed Central

    Goyens, Jana; Van Wassenbergh, Sam; Dirckx, Joris; Aerts, Peter

    2015-01-01

    Male stag beetles have evolved extremely large mandibles in a wide range of extraordinary shapes. These mandibles function as weaponry in pugnacious fights for females. The robust mandibles of Cyclommatus metallifer are as long as their own body and their enlarged head houses massive, hypertrophied musculature. Owing to this disproportional weaponry, trade-offs exist with terrestrial locomotion: running is unstable and approximately 40% more costly. Therefore, flying is most probably essential to cover larger distances towards females and nesting sites. We hypothesized that weight, size and shape of the weaponry will affect flight performance. Our computational fluid dynamics simulations of steady-state models (without membrane wings) reveal that male stag beetles must deliver 26% more mechanical work to fly with their heavy weaponry. This extra work is almost entirely required to carry the additional weight of the massive armature. The size and shape of the mandibles have only negligible influence on flight performance (less than 0.1%). This indicates that the evolution of stag beetle weaponry is constrained by its excessive weight, not by the size or shape of the mandibles and head as such. This most probably paved the way for the wide diversity of extraordinary mandible morphologies that characterize the stag beetle family. PMID:25878126

  5. Cantharimide dimers from the Chinese blister beetle, Mylabris phalerate PALLAS.

    PubMed

    Nakatani, Takafumi; Jinpo, Katsuaki; Noda, Naoki

    2007-01-01

    Five cantharidin-related compounds were isolated from the Chinese blister beetle, Mylabris phalerate PALLAS (Meloidae). Their structures were determined based on spectroscopic and chemical evidence. Three of them were identified as cantharimide dimers, which consist of two units of cantharimide combined with a tri-, tetra-, or penta-methylene group. PMID:17202708

  6. Evaluation of factors impacting trap captures of red flour beetle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An effective monitoring program is the foundation of good Integrated Pest Management programs for food facilities such as mills, processing plants, warehouses, and retail stores. The red flour beetle, Tribolium castaneum, is a major stored-product pest of food facilities, especially mills, and a nu...

  7. Current status of small hive beetle infestation in the Philippines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The distribution of the small hive beetle (SHB, Aethina tumida) is rapidly expanding. From sub-Saharan Africa where it is considered indigenous, SHB has successfully invaded other continents, is prevalent in Australia and North America, and has recently been introduced into Europe (summarized by FE...

  8. [Co-adaptation between mites (Arachnida: Klinckowstroemiidae) and Passalidae beetles (Insecta: Coleoptera)].

    PubMed

    Villegas-Guzmán, Gabriel A; Francke, Oscar F; Pérez, Tila M; Reyes-Castillo, Pedro

    2012-06-01

    Mites of the family Klinckowstroemiidae establish an association with beetles of the family Passalidae known as phoresy. In order to obtain information about this association, we analyzed the relationship between mites of the family Klinckowstroemiidae and beetles of the family Passalidae, as adult mites have been exclusively collected from host beetles. We examined 1 150 beetles collected in seven states of the Mexican Republic, and found 19 species of klinckowstroemiid mites associated with 168 passalids, that belong to 28 different species in 15 genera. Host specificity between species of both groups does not exist, as one species of passalid beetle can have several different symbionts; conversely, a given mite species can associate with passalid beetles of different species and even of different genera. This way, Odontotaenius zodiacus has been found associated with mites of seven species of the genus Klinckowstroemia. Besides, Klinckowstroemia valdezi is associated with five species of passalids. Furthermore, two and even three different species of mites have been found on one host beetle (synhospitality). The lack of congruence between the phylogenies of the mites and that of the beetles indicates that a process of co-adaptation by colonization is going on, because the association is due to the resources that passalid beetles can offer to the mites, like transportation, food and refuge. Since these resources are not host-specific, the klinckowstroemiid mites can climb onto virtually any species of passalid beetles occurring on the same habitat.

  9. Spatio-Temporal Distribution of Bark and Ambrosia Beetles in a Brazilian Tropical Dry Forest.

    PubMed

    Macedo-Reis, Luiz Eduardo; Novais, Samuel Matos Antunes de; Monteiro, Graziela França; Flechtmann, Carlos Alberto Hector; Faria, Maurício Lopes de; Neves, Frederico de Siqueira

    2016-01-01

    Bark and the ambrosia beetles dig into host plants and live most of their lives in concealed tunnels. We assessed beetle community dynamics in tropical dry forest sites in early, intermediate, and late successional stages, evaluating the influence of resource availability and seasonal variations in guild structure. We collected a total of 763 beetles from 23 species, including 14 bark beetle species, and 9 ambrosia beetle species. Local richness of bark and ambrosia beetles was estimated at 31 species. Bark and ambrosia composition was similar over the successional stages gradient, and beta diversity among sites was primarily determined by species turnover, mainly in the bark beetle community. Bark beetle richness and abundance were higher at intermediate stages; availability of wood was the main spatial mechanism. Climate factors were effectively non-seasonal. Ambrosia beetles were not influenced by successional stages, however the increase in wood resulted in increased abundance. We found higher richness at the end of the dry and wet seasons, and abundance increased with air moisture and decreased with higher temperatures and greater rainfall. In summary, bark beetle species accumulation was higher at sites with better wood production, while the needs of fungi (host and air moisture), resulted in a favorable conditions for species accumulation of ambrosia. The overall biological pattern among guilds differed from tropical rain forests, showing patterns similar to dry forest areas. PMID:27271969

  10. Comparative water relations of adult and juvenile tortoise beetles: differences among sympatric species.

    PubMed

    Hull-Sanders, Helen M; Appel, Arthur G; Eubanks, Micky D

    2003-08-01

    Relative abundance of two sympatric tortoise beetles varies between drought and 'wet' years. Differing abilities to conserve water may influence beetle survival in changing environments. Cuticular permeability (CP), percentage of total body water (%TBW), rate of water loss and percentage of body lipid content were determined for five juvenile stages and female and male adults of two sympatric species of chrysomelid beetles, the golden tortoise beetle, Charidotella bicolor (F.) and the mottled tortoise beetle, Deloyala guttata (Olivier). There were significant differences in %TBW and lipid content among juvenile stages. Second instars had the greatest difference in CP (37.98 and 11.13 microgcm(-2)h(-1)mmHg(-1) for golden and mottled tortoise beetles, respectively). Mottled tortoise beetles had lower CP and greater %TBW compared with golden tortoise beetles, suggesting that they can conserve a greater amount of water and may tolerate drier environmental conditions. This study suggests that juvenile response to environmental water stress may differentially affect the survival of early instars and thus affect the relative abundance of adult beetles in the field. This is supported by the low relative abundance of golden tortoise beetle larvae in a drought year and the higher abundance in two 'wet' years.

  11. Spatio-Temporal Distribution of Bark and Ambrosia Beetles in a Brazilian Tropical Dry Forest.

    PubMed

    Macedo-Reis, Luiz Eduardo; Novais, Samuel Matos Antunes de; Monteiro, Graziela França; Flechtmann, Carlos Alberto Hector; Faria, Maurício Lopes de; Neves, Frederico de Siqueira

    2016-01-01

    Bark and the ambrosia beetles dig into host plants and live most of their lives in concealed tunnels. We assessed beetle community dynamics in tropical dry forest sites in early, intermediate, and late successional stages, evaluating the influence of resource availability and seasonal variations in guild structure. We collected a total of 763 beetles from 23 species, including 14 bark beetle species, and 9 ambrosia beetle species. Local richness of bark and ambrosia beetles was estimated at 31 species. Bark and ambrosia composition was similar over the successional stages gradient, and beta diversity among sites was primarily determined by species turnover, mainly in the bark beetle community. Bark beetle richness and abundance were higher at intermediate stages; availability of wood was the main spatial mechanism. Climate factors were effectively non-seasonal. Ambrosia beetles were not influenced by successional stages, however the increase in wood resulted in increased abundance. We found higher richness at the end of the dry and wet seasons, and abundance increased with air moisture and decreased with higher temperatures and greater rainfall. In summary, bark beetle species accumulation was higher at sites with better wood production, while the needs of fungi (host and air moisture), resulted in a favorable conditions for species accumulation of ambrosia. The overall biological pattern among guilds differed from tropical rain forests, showing patterns similar to dry forest areas.

  12. Spatio-Temporal Distribution of Bark and Ambrosia Beetles in a Brazilian Tropical Dry Forest

    PubMed Central

    de Novais, Samuel Matos Antunes; Monteiro, Graziela França; Flechtmann, Carlos Alberto Hector; de Faria, Maurício Lopes; Neves, Frederico de Siqueira

    2016-01-01

    Bark and the ambrosia beetles dig into host plants and live most of their lives in concealed tunnels. We assessed beetle community dynamics in tropical dry forest sites in early, intermediate, and late successional stages, evaluating the influence of resource availability and seasonal variations in guild structure. We collected a total of 763 beetles from 23 species, including 14 bark beetle species, and 9 ambrosia beetle species. Local richness of bark and ambrosia beetles was estimated at 31 species. Bark and ambrosia composition was similar over the successional stages gradient, and beta diversity among sites was primarily determined by species turnover, mainly in the bark beetle community. Bark beetle richness and abundance were higher at intermediate stages; availability of wood was the main spatial mechanism. Climate factors were effectively non-seasonal. Ambrosia beetles were not influenced by successional stages, however the increase in wood resulted in increased abundance. We found higher richness at the end of the dry and wet seasons, and abundance increased with air moisture and decreased with higher temperatures and greater rainfall. In summary, bark beetle species accumulation was higher at sites with better wood production, while the needs of fungi (host and air moisture), resulted in a favorable conditions for species accumulation of ambrosia. The overall biological pattern among guilds differed from tropical rain forests, showing patterns similar to dry forest areas. PMID:27271969

  13. Interactions between imidacloprid and Metarhizium brunneum on adult Asian longhorned beetles (Anoplophora glabripennis (Motschulsky)) (Coleoptera: Cerambycidae).

    PubMed

    Russell, Calum W; Ugine, Todd A; Hajek, Ann E

    2010-11-01

    Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), a longhorned beetle species native to Asia, has been introduced into several North American and European cities. Currently eradication and preventive measures are limited to identifying and destroying infested trees and protecting uninfested trees with trunk or soil-injections of the systemic insecticide imidacloprid. Because entomopathogenic fungi like Metarhizium brunneum Petch have been identified as virulent against these beetles we conducted several tests to determine the compatibility of the two agents in combination. Radial hyphal growth and the sporulation capacity of M. brunneum on Sabouraud dextrose agar with yeast were not significantly affected by the presence of imidacloprid. In a 2×3 factorial experiment investigating interactions between exposure to imidacloprid and M. brunneum we observed no effect of imidacloprid alone on beetle survival when beetles were given a single dose of 10 or 100 ppm compared to control insects. We observed a significant effect of exposure to M. brunneum, and a significant interaction between imidacloprid and M. brunneum representing a synergistic effect of dual treatment. Beetles exposed to the fungus alone lived significantly longer compared to insects treated with a single dose of 100 ppm imidacloprid (9.5 vs. 6.5d). Consumption of striped maple twigs by beetles exposed to imidacloprid, across concentrations, was reduced 48% compared to control insects, where as consumption by M. brunneum-exposed beetles was reduced by 16% over the first 6-days of the test period. Beetles fed 100 ppm imidacloprid consumed 32% less over the first 3d compared to beetles not exposed to imidacloprid and thereafter consumed as much as beetles not fed 100 ppm imidacloprid. M. brunneum-exposed beetles consumed significantly less food than control insects throughout the test period, and beetles treated with imidacloprid produced significantly fewer conidia compared to beetles

  14. Juvenile hormone regulates extreme mandible growth in male stag beetles.

    PubMed

    Gotoh, Hiroki; Cornette, Richard; Koshikawa, Shigeyuki; Okada, Yasukazu; Lavine, Laura Corley; Emlen, Douglas J; Miura, Toru

    2011-01-01

    The morphological diversity of insects is one of the most striking phenomena in biology. Evolutionary modifications to the relative sizes of body parts, including the evolution of traits with exaggerated proportions, are responsible for a vast range of body forms. Remarkable examples of an insect trait with exaggerated proportions are the mandibular weapons of stag beetles. Male stag beetles possess extremely enlarged mandibles which they use in combat with rival males over females. As with other sexually selected traits, stag beetle mandibles vary widely in size among males, and this variable growth results from differential larval nutrition. However, the mechanisms responsible for coupling nutrition with growth of stag beetle mandibles (or indeed any insect structure) remain largely unknown. Here, we demonstrate that during the development of male stag beetles (Cyclommatus metallifer), juvenile hormone (JH) titers are correlated with the extreme growth of an exaggerated weapon of sexual selection. We then investigate the putative role of JH in the development of the nutritionally-dependent, phenotypically plastic mandibles, by increasing hemolymph titers of JH with application of the JH analog fenoxycarb during larval and prepupal developmental periods. Increased JH signaling during the early prepupal period increased the proportional size of body parts, and this was especially pronounced in male mandibles, enhancing the exaggerated size of this trait. The direction of this response is consistent with the measured JH titers during this same period. Combined, our results support a role for JH in the nutrition-dependent regulation of extreme mandible growth in this species. In addition, they illuminate mechanisms underlying the evolution of trait proportion, the most salient feature of the evolutionary diversification of the insects.

  15. Urban soil biomonitoring by beetle and earthworm populations

    SciTech Connect

    Janossy, L.; Bitto, A.

    1995-12-31

    Two macro invertebrate groups were chosen for biomonitoring environmental changes. The beetle population was pitfall trapped (five month in 1994) at five downtown sites (parks) of Budapest and in a hilly original woodland as a control site 33km NW of Budapest. Earthworms were collected by using formol solution. Five heavy metals were measured (Pb, Co, Hg, Zn, Cu) in the upper soil layer at the same sampling sites. Pb, Hg, Zn and Cu was over the tolerable limit in a park near the railway, extreme high Pb (530 mg/kg dry soil) and Zn content was measured in one park. Roads are also salted in wintertime. The number of beetle species in the downtown parks varied 10 to 22 (226--462 specimen). Near to the edge of the city up to 45 beetle species were found in a park with 1,027 specimen. In the woodland area 52 beetle species with 1,061 specimen were found. Less dominance and higher specific diversity showed the direction from downtown to woodland. Only 2 or 3 cosmopolitan earthworm species existed in downtown parks with 30--35 specimen/m{sup 2}, in the control woodland area 7 mostly endemic earthworm species were found with 74 specimens/m{sup 2}. But earthworm biomass was higher in three well fertilized parks (43--157 g/m{sup 2}), than in the original woodland (25-g/m{sup 2}). The beetle populations seem to be good tools for biomonitoring. Earthworms are susceptible to environmental changes but they also strongly depend on the leaf litter and the organic matter of the soil. The change in the animal populations is the result of summarized environmental impacts in such a big city like Budapest.

  16. Mountain pine beetle-caused mortality over eight years in two pine hosts in mixed conifer stands of the southern Rocky Mountains

    USGS Publications Warehouse

    West, Daniel R.; Briggs, Jennifer S.; Jacobi, William R.; Negrón, José F.

    2014-01-01

    Eruptive mountain pine beetle (Dendroctonus ponderosae, MPB) populations have caused widespread mortality of pines throughout western North America since the late 1990s. Early work by A.D. Hopkins suggested that when alternate host species are available, MPB will prefer to breed in the host to which it has become adapted. In Colorado, epidemic MPB populations that originated in lodgepole pine expanded into mixed-conifer stands containing ponderosa pine, a related host. We evaluated the susceptibility of both hosts to successful MPB colonization in a survey of 19 sites in pine-dominated mixed-conifer stands spanning 140 km of the Front Range, CO, USA. In each of three 0.2-ha plots at each site, we (1) assessed trees in the annual flights of 2008–2011 to compare MPB-caused mortality between lodgepole and ponderosa pine; (2) recorded previous MPB-caused tree mortality from 2004–2007 to establish baseline mortality levels; and (3) measured characteristics of the stands (e.g. tree basal area) and sites (e.g. elevation, aspect) that might be correlated with MPB colonization. Uninfested average live basal area of lodgepole and ponderosa pine was 74% of total basal area before 2004. We found that for both species, annual percent basal area of attacked trees was greatest in one year (2009), and was lower in all other years (2004–2007, 2008, 2010, and 2011). Both pine species had similar average total mortality of 38–39% by 2011. Significant predictors of ponderosa pine mortality in a given year were basal area of uninfested ponderosa pine and the previous year’s mortality levels in both ponderosa and lodgepole pine. Lodgepole pine mortality was predicted by uninfested basal areas of both lodgepole and ponderosa pine, and the previous year’s lodgepole pine mortality. These results indicate host selection by MPB from lodgepole pine natal hosts into ponderosa pine the following year, but not the reverse. In both species, diameters of attacked trees within each year

  17. Population Structure of Mountain Pine Beetle Symbiont Leptographium longiclavatum and the Implication on the Multipartite Beetle-Fungi Relationships

    PubMed Central

    Tsui, Clement Kin-Ming; Farfan, Lina; Roe, Amanda D.; Rice, Adrianne V.; Cooke, Janice E. K.; El-Kassaby, Yousry A.; Hamelin, Richard C.

    2014-01-01

    Over 18 million ha of forests have been destroyed in the past decade in Canada by the mountain pine beetle (MPB) and its fungal symbionts. Understanding their population dynamics is critical to improving modeling of beetle epidemics and providing potential clues to predict population expansion. Leptographium longiclavatum and Grosmannia clavigera are fungal symbionts of MPB that aid the beetle to colonize and kill their pine hosts. We investigated the genetic structure and demographic expansion of L. longiclavatum in populations established within the historic distribution range and in the newly colonized regions. We identified three genetic clusters/populations that coincide with independent geographic locations. The genetic profiles of the recently established populations in northern British Columbia (BC) and Alberta suggest that they originated from central and southern BC. Approximate Bayesian Computation supports the scenario that this recent expansion represents an admixture of individuals originating from BC and the Rocky Mountains. Highly significant correlations were found among genetic distance matrices of L. longiclavatum, G. clavigera, and MPB. This highlights the concordance of demographic processes in these interacting organisms sharing a highly specialized niche and supports the hypothesis of long-term multipartite beetle-fungus co-evolutionary history and mutualistic relationships. PMID:25153489

  18. Population structure of mountain pine beetle symbiont Leptographium longiclavatum and the implication on the multipartite beetle-fungi relationships.

    PubMed

    Tsui, Clement Kin-Ming; Farfan, Lina; Roe, Amanda D; Rice, Adrianne V; Cooke, Janice E K; El-Kassaby, Yousry A; Hamelin, Richard C

    2014-01-01

    Over 18 million ha of forests have been destroyed in the past decade in Canada by the mountain pine beetle (MPB) and its fungal symbionts. Understanding their population dynamics is critical to improving modeling of beetle epidemics and providing potential clues to predict population expansion. Leptographium longiclavatum and Grosmannia clavigera are fungal symbionts of MPB that aid the beetle to colonize and kill their pine hosts. We investigated the genetic structure and demographic expansion of L. longiclavatum in populations established within the historic distribution range and in the newly colonized regions. We identified three genetic clusters/populations that coincide with independent geographic locations. The genetic profiles of the recently established populations in northern British Columbia (BC) and Alberta suggest that they originated from central and southern BC. Approximate Bayesian Computation supports the scenario that this recent expansion represents an admixture of individuals originating from BC and the Rocky Mountains. Highly significant correlations were found among genetic distance matrices of L. longiclavatum, G. clavigera, and MPB. This highlights the concordance of demographic processes in these interacting organisms sharing a highly specialized niche and supports the hypothesis of long-term multipartite beetle-fungus co-evolutionary history and mutualistic relationships. PMID:25153489

  19. Population structure of mountain pine beetle symbiont Leptographium longiclavatum and the implication on the multipartite beetle-fungi relationships.

    PubMed

    Tsui, Clement Kin-Ming; Farfan, Lina; Roe, Amanda D; Rice, Adrianne V; Cooke, Janice E K; El-Kassaby, Yousry A; Hamelin, Richard C

    2014-01-01

    Over 18 million ha of forests have been destroyed in the past decade in Canada by the mountain pine beetle (MPB) and its fungal symbionts. Understanding their population dynamics is critical to improving modeling of beetle epidemics and providing potential clues to predict population expansion. Leptographium longiclavatum and Grosmannia clavigera are fungal symbionts of MPB that aid the beetle to colonize and kill their pine hosts. We investigated the genetic structure and demographic expansion of L. longiclavatum in populations established within the historic distribution range and in the newly colonized regions. We identified three genetic clusters/populations that coincide with independent geographic locations. The genetic profiles of the recently established populations in northern British Columbia (BC) and Alberta suggest that they originated from central and southern BC. Approximate Bayesian Computation supports the scenario that this recent expansion represents an admixture of individuals originating from BC and the Rocky Mountains. Highly significant correlations were found among genetic distance matrices of L. longiclavatum, G. clavigera, and MPB. This highlights the concordance of demographic processes in these interacting organisms sharing a highly specialized niche and supports the hypothesis of long-term multipartite beetle-fungus co-evolutionary history and mutualistic relationships.

  20. A Survey of Dung Beetles Infected with Larval Nematodes with Particular Note on Copris lunaris Beetles as a Vector for Gongylonema sp. in Iran

    PubMed Central

    Mikaeili, Elmira; Mobedi, Iraj; Kia, Eshratbeigom; Masoomi, Lotfali; Vatandoost, Hassan

    2009-01-01

    Dung beetles (family Scarabaeidae) are one of the largest families of beetles worldwide. Due to biological behavior of these arthropods, they are considered to play an important role in the life cycle of some helminths. In the present study, dung beetles collected from cattle pastures in rural areas of Ardabil province, north-west of Iran were examined for infection with larval stages of helminths. According to the results, nematodes of 2 genera were identified including Rhabditis and Gongylonema. The more common species was Rhabditis sp. which was found in 9 species of beetles. Out of 15 different species of dung beetles, Copris lunaris was the only scarabaeid to be found naturally infected with the larval stages of Gongylonema sp. Our new findings introduce C. lunaris as a potential biological vector for transmission of Gongylonema sp. to vertebrates in the surveyed region. PMID:19290086

  1. Small beetle, large-scale drivers: how regional and landscape factors affect outbreaks of the European spruce bark beetle

    PubMed Central

    Seidl, Rupert; Müller, Jörg; Hothorn, Torsten; Bässler, Claus; Heurich, Marco; Kautz, Markus

    2016-01-01

    Summary 1. Unprecedented bark beetle outbreaks have been observed for a variety of forest ecosystems recently, and damage is expected to further intensify as a consequence of climate change. In Central Europe, the response of ecosystem management to increasing infestation risk has hitherto focused largely on the stand level, while the contingency of outbreak dynamics on large-scale drivers remains poorly understood. 2. To investigate how factors beyond the local scale contribute to the infestation risk from Ips typographus (Col., Scol.), we analysed drivers across seven orders of magnitude in scale (from 103 to 1010 m2) over a 23-year period, focusing on the Bavarian Forest National Park. Time-discrete hazard modelling was used to account for local factors and temporal dependencies. Subsequently, beta regression was applied to determine the influence of regional and landscape factors, the latter characterized by means of graph theory. 3. We found that in addition to stand variables, large-scale drivers also strongly influenced bark beetle infestation risk. Outbreak waves were closely related to landscape-scale connectedness of both host and beetle populations as well as to regional bark beetle infestation levels. Furthermore, regional summer drought was identified as an important trigger for infestation pulses. Large-scale synchrony and connectivity are thus key drivers of the recently observed bark beetle outbreak in the area. 4. Synthesis and applications. Our multiscale analysis provides evidence that the risk for biotic disturbances is highly dependent on drivers beyond the control of traditional stand-scale management. This finding highlights the importance of fostering the ability to cope with and recover from disturbance. It furthermore suggests that a stronger consideration of landscape and regional processes is needed to address changing disturbance regimes in ecosystem management. PMID:27041769

  2. Predaceous diving beetles in Maine: Faunal list and keys to subfamilies

    USGS Publications Warehouse

    Boobar, L.R.; Spangler, P.J.; Gibbs, K.E.; Longcore, J.R.; Hopkins, K.M.

    1998-01-01

    Records of predaceous diving beetles (Coleoptera: Dytiscidae) collected in Maine are summarized. These records are augmented by field surveys of beetles in Aroostook Co., Maine during 1993-95. Keys to subfamilies are presented with color plates for selected species. A list of diving beetles that have been collected near Maine (state or province) is presented so that investigators will know what additional species might be expected in Maine. Basic taxonomy is presented to facilitate use of keys.

  3. Ophiostoma ips from Pinewood Nematode Vector, Japanese Pine Sawyer Beetle (Monochamus alternatus), in Korea

    PubMed Central

    Suh, Dong Yeon; Hyun, Min Woo; Kim, Jae Jin; Son, Seung Yeol

    2013-01-01

    Japanese pine sawyer beetle (Monochamus alternatus) is an economically important pest in coniferous trees. Ophiostoma ips was isolated from the beetle and identified based on analysis of morphological properties and the β-tubulin gene sequence. The fungus easily produced perithecia with a long neck on malt extract agar and its ascospores were rectangular shaped. This is first report of Ophiostoma species associated with the pinewood nematode vector beetle in Korea. PMID:23610541

  4. Polarizing properties and structure of the cuticle of scarab beetles from the Chrysina genus.

    PubMed

    Fernández Del Río, Lía; Arwin, Hans; Järrendahl, Kenneth

    2016-07-01

    The optical properties of several scarab beetles have been previously studied but few attempts have been made to compare beetles in the same genus. To determine whether there is any relation between specimens of the same genus, we have studied and classified seven species from the Chrysina genus. The polarization properties were analyzed with Mueller-matrix spectroscopic ellipsometry and the structural characteristics with optical microscopy and scanning electron microscopy. Most of the Chrysina beetles are green colored or have a metallic look (gold or silver). The results show that the green-colored beetles polarize reflected light mainly at off-specular angles. The gold-colored beetles polarize light left-handed near circular at specular reflection. The structure of the exoskeleton is a stack of layers that form a cusplike structure in the green beetles whereas the layers are parallel to the surface in the case of the gold-colored beetles. The beetle C. gloriosa is green with gold-colored stripes along the elytras and exhibits both types of effects. The results indicate that Chrysina beetles can be classified according to these two major polarization properties. PMID:27575166

  5. Polarizing properties and structure of the cuticle of scarab beetles from the Chrysina genus

    NASA Astrophysics Data System (ADS)

    Fernández del Río, Lía; Arwin, Hans; Järrendahl, Kenneth

    2016-07-01

    The optical properties of several scarab beetles have been previously studied but few attempts have been made to compare beetles in the same genus. To determine whether there is any relation between specimens of the same genus, we have studied and classified seven species from the Chrysina genus. The polarization properties were analyzed with Mueller-matrix spectroscopic ellipsometry and the structural characteristics with optical microscopy and scanning electron microscopy. Most of the Chrysina beetles are green colored or have a metallic look (gold or silver). The results show that the green-colored beetles polarize reflected light mainly at off-specular angles. The gold-colored beetles polarize light left-handed near circular at specular reflection. The structure of the exoskeleton is a stack of layers that form a cusplike structure in the green beetles whereas the layers are parallel to the surface in the case of the gold-colored beetles. The beetle C. gloriosa is green with gold-colored stripes along the elytras and exhibits both types of effects. The results indicate that Chrysina beetles can be classified according to these two major polarization properties.

  6. Checklist of leaf beetles (Coleoptera: Chrysomelidae) from the state of Morelos, Mexico.

    PubMed

    Niño-Maldonado, Santiago; Sánchez-Reyes, Uriel Jeshua; Clark, Shawn M; Toledo-Hernández, Victor Hugo; Corona-López, Angélica María; Jones, Robert W

    2016-03-07

    We record 116 genera and 366 species of Chrysomelidae from the state of Morelos, Mexico. This represents an increase of 9.3% in the species richness of these beetles for the state. Also, Morelos is currently the third most diverse state in leaf beetles within Mexico, with 16.78% of total species recorded for the country. The most diverse genera were Calligrapha, Disonycha, Blepharida, Leptinotarsa, Cryptocephalus, Systena, Alagoasa, Diabrotica and Pachybrachis, each with more than eight species. Most of these genera contain large, showy beetles. When the chrysomelid fauna is more fully understood, some of the genera of tiny beetles will likely prove to be more diverse.

  7. Social encapsulation of beetle parasites by Cape honeybee colonies (Apis mellifera capensis Esch.)

    NASA Astrophysics Data System (ADS)

    Neumann, P.; Pirk, C. W. W.; Hepburn, H. R.; Solbrig, A. J.; Ratnieks, F. L. W.; Elzen, P. J.; Baxter, J. R.

    2001-05-01

    Worker honeybees (Apis mellifera capensis) encapsulate the small hive beetle (Aethina tumida), a nest parasite, in propolis (tree resin collected by the bees). The encapsulation process lasts 1-4 days and the bees have a sophisticated guarding strategy for limiting the escape of beetles during encapsulation. Some encapsulated beetles died (4.9%) and a few escaped (1.6%). Encapsulation has probably evolved because the small hive beetle cannot easily be killed by the bees due to its hard exoskeleton and defensive behaviour.

  8. Repeated evolution of crop theft in fungus-farming ambrosia beetles.

    PubMed

    Hulcr, Jiri; Cognato, Anthony I

    2010-11-01

    Ambrosia beetles, dominant wood degraders in the tropics, create tunnels in dead trees and employ gardens of symbiotic fungi to extract nutrients from wood. Specificity of the beetle-fungus relationship has rarely been examined, and simple vertical transmission of a specific fungal cultivar by each beetle species is often assumed in literature. We report repeated evolution of fungal crop stealing, termed mycocleptism, among ambrosia beetles. The mycocleptic species seek brood galleries of other species, and exploit their established fungal gardens by tunneling through the ambient mycelium-laden wood. Instead of carrying their own fungal sybmbionts, mycocleptae depend on adopting the fungal assemblages of their host species, as shown by an analysis of fungal DNA from beetle galleries. The evidence for widespread horizontal exchange of fungi between beetles challenges the traditional concept of ambrosia fungi as species-specific symbionts. Fungus stealing appears to be an evolutionarily successful strategy. It evolved independently in several beetle clades, two of which have radiated, and at least one case was accompanied by a loss of the beetles' fungus-transporting organs. We demonstrate this using the first robust phylogeny of one of the world's largest group of ambrosia beetles, Xyleborini. PMID:20633043

  9. Ethanol injection of ornamental trees facilitates testing insecticide efficacy against ambrosia beetles (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Reding, Michael E; Oliver, Jason B; Schultz, Peter B; Ranger, Christopher M; Youssef, Nadeer N

    2013-02-01

    Exotic ambrosia beetles are damaging pests in ornamental tree nurseries in North America. The species Xylosandrus crassiusculus (Motshulsky) and Xylosandrus germanus (Blandford) are especially problematic. Management of these pests relies on preventive treatments of insecticides. However, field tests of recommended materials on nursery trees have been limited because of unreliable attacks by ambrosia beetles on experimental trees. Ethanol-injection of trees was used to induce colonization by ambrosia beetles to evaluate insecticides and botanical formulations for preventing attacks by ambrosia beetles. Experiments were conducted in Ohio, Tennessee, and Virginia. Experimental trees injected with ethanol had more attacks by ambrosia beetles than uninjected control trees in all but one experiment. Xylosandrus crassiusculus and X. germanus colonized trees injected with ethanol. In most experiments, attack rates declined 8 d after ethanol-injection. Ethanol-injection induced sufficient pressure from ambrosia beetles to evaluate the efficacy of insecticides for preventing attacks. Trunk sprays of permethrin suppressed cumulative total attacks by ambrosia beetles in most tests. Trunk sprays of the botanical formulations Armorex and Veggie Pharm suppressed cumulative total attacks in Ohio. Armorex, Armorex + Permethrin, and Veggie Pharm + Permethrin suppressed attacks in Tennessee. The bifenthrin product Onyx suppressed establishment of X. germanus in one Ohio experiment, and cumulative total ambrosia beetle attacks in Virginia. Substrate drenches and trunk sprays of neonicotinoids, or trunk sprays of anthranilic diamides or tolfenpyrad were not effective. Ethanol-injection is effective for inducing attacks and ensuring pressure by ambrosia beetles for testing insecticide efficacy on ornamental trees.

  10. IMPACT OF IMMUNE RESPONSE OF A PARASITIC BEETLE Dastarcus helophoroides ON ITS HOST BEETLE Monochamus alternatus.

    PubMed

    Li, Xiao-Juan; Dong, Guang-Ping; Fang, Jian-Min; Liu, Hong-Jian; Yang, Li; Guo, Wan-Lin

    2015-09-01

    Dastarcus helophoroides is an ectoparasitoid beetle of Monochamus alternatus, and the parasitism by D. helophoroides larvae remarkably influenced on the immune responses of M. alternatus larvae in many aspects. The hemolymph melanization reactions in the hosts were inhibited 1 h and 24 h postparasitization. The phenoloxidase activities of hemolymph were significantly stimulated 4 h postparasitization and inhibited 12 h postparasitization, and back to control level. The antibacterial activities of hemolymph in the parasitized hosts were significantly lower than that in the unparasitized ones 1 h postparasitization. By 72 h postparasitism, the total hemocyte numbers of the parasitized larvae declined to not more than one-seconds of the number collected from the unparasitized larvae. All sampled hemolymph held the capability of nodulation, and there were fluctuations in the number of nodules the hemocytes made. However, there were no significant differences between unparasitized and parasitized larvae at each time point in the hemagglutination activity and the ratios of spreading hemocytes. In conclusion, D. helophoroides larvae could regulate M. alternatus immune system and resulted in the changes in host immune responses.

  11. Bright-White Beetle Scales Optimise Multiple Scattering of Light

    NASA Astrophysics Data System (ADS)

    Burresi, Matteo; Cortese, Lorenzo; Pattelli, Lorenzo; Kolle, Mathias; Vukusic, Peter; Wiersma, Diederik S.; Steiner, Ullrich; Vignolini, Silvia

    2014-08-01

    Whiteness arises from diffuse and broadband reflection of light typically achieved through optical scattering in randomly structured media. In contrast to structural colour due to coherent scattering, white appearance generally requires a relatively thick system comprising randomly positioned high refractive-index scattering centres. Here, we show that the exceptionally bright white appearance of Cyphochilus and Lepidiota stigma beetles arises from a remarkably optimised anisotropy of intra-scale chitin networks, which act as a dense scattering media. Using time-resolved measurements, we show that light propagating in the scales of the beetles undergoes pronounced multiple scattering that is associated with the lowest transport mean free path reported to date for low-refractive-index systems. Our light transport investigation unveil high level of optimisation that achieves high-brightness white in a thin low-mass-per-unit-area anisotropic disordered nanostructure.

  12. Associational Patterns of Scavenger Beetles to Decomposition Stages.

    PubMed

    Zanetti, Noelia I; Visciarelli, Elena C; Centeno, Nestor D

    2015-07-01

    Beetles associated with carrion play an important role in recycling organic matter in an ecosystem. Four experiments on decomposition, one per season, were conducted in a semirural area in Bahía Blanca, Argentina. Melyridae are reported for the first time of forensic interest. Apart from adults and larvae of Scarabaeidae, thirteen species and two genera of other coleopteran families are new forensic records in Argentina. Diversity, abundance, and species composition of beetles showed differences between stages and seasons. Our results differed from other studies conducted in temperate regions. Four guilds and succession patterns were established in relation to decomposition stages and seasons. Dermestidae (necrophages) predominated in winter during the decomposition process; Staphylinidae (necrophiles) in Fresh and Bloat stages during spring, summer, and autumn; and Histeridae (necrophiles) and Cleridae (omnivores) in the following stages during those seasons. Finally, coleopteran activity, diversity and abundance, and decomposition rate change with biogeoclimatic characteristics, which is of significance in forensics. PMID:26174466

  13. Simulation of light scattering from exoskeletons of scarab beetles.

    PubMed

    Valyukh, Sergiy; Arwin, Hans; Järrendahl, Kenneth

    2016-03-21

    An approach for simulation of light scattering from beetles exhibiting structural colors originating from periodic helicoidal structures is presented. Slight irregularities of the periodic structure in the exoskeleton of the beetles are considered as a major cause of light scattering. Two sources of scattering are taken into account: surface roughness and volume non-uniformity. The Kirchhoff approximation is applied to simulate the effect of surface roughness. To describe volume non-uniformity, the whole structure is modeled as a set of domains distributed in space in different orientations. Each domain is modeled as an ideal uniformly twisted uniaxial medium and differs from each other by the pitch. Distributions of the domain parameters are assumed to be Gaussian. The analysis is performed using the Mueller matrix formalism which, in addition to spectral and spatial characteristics, also provides polarization properties of the scattered light. PMID:27136777

  14. Biology, ecology, and control of elaterid beetles in agricultural land.

    PubMed

    Traugott, Michael; Benefer, Carly M; Blackshaw, Rod P; van Herk, Willem G; Vernon, Robert S

    2015-01-01

    Wireworms, the larvae of click beetles (Coleoptera: Elateridae), have had a centuries-long role as major soil insect pests worldwide. With insecticidal control options dwindling, research on click beetle biology and ecology is of increasing importance in the development of new control tactics. Methodological improvements have deepened our understanding of how larvae and adults spatially and temporarily utilize agricultural habitats and interact with their environment. This progress, however, rests with a few pest species, and efforts to obtain comparable knowledge on other economically important elaterids are crucial. There are still considerable gaps in our understanding of female and larval ecology; movement of elaterids within landscapes; and the impact of natural enemies, cultivation practices, and environmental change on elaterid population dynamics. This knowledge will allow generation of multifaceted control strategies, including cultural, physical, and chemical measures, tailored toward species complexes and crops across a range of appropriate spatial scales. PMID:25341096

  15. Bright-white beetle scales optimise multiple scattering of light.

    PubMed

    Burresi, Matteo; Cortese, Lorenzo; Pattelli, Lorenzo; Kolle, Mathias; Vukusic, Peter; Wiersma, Diederik S; Steiner, Ullrich; Vignolini, Silvia

    2014-01-01

    Whiteness arises from diffuse and broadband reflection of light typically achieved through optical scattering in randomly structured media. In contrast to structural colour due to coherent scattering, white appearance generally requires a relatively thick system comprising randomly positioned high refractive-index scattering centres. Here, we show that the exceptionally bright white appearance of Cyphochilus and Lepidiota stigma beetles arises from a remarkably optimised anisotropy of intra-scale chitin networks, which act as a dense scattering media. Using time-resolved measurements, we show that light propagating in the scales of the beetles undergoes pronounced multiple scattering that is associated with the lowest transport mean free path reported to date for low-refractive-index systems. Our light transport investigation unveil high level of optimisation that achieves high-brightness white in a thin low-mass-per-unit-area anisotropic disordered nanostructure. PMID:25123449

  16. Structural origin of circularly polarized iridescence in jeweled beetles

    NASA Astrophysics Data System (ADS)

    Crne, Matija; Sharma, Vivek; Park, Jung O.; Srinivasarao, Mohan

    2010-03-01

    The iridescent metallic green beetle, Chrysina gloriosa, selectively reflects left circularly polarized light. The exoskeleton is decorated by hexagonal cells (˜10 micron) that coexist with pentagons and heptagons. We find that the fraction of hexagons decreases with an increase in curvature. In bright field microscopy, each cell contains a bright yellow core, placed in a greenish cell with yellowish border, but the core disappears in the dark field. Using confocal microscopy, we observe that these cells consist of nearly concentric, nested arcs that lie on surface of a shallow cone. We infer that the patterns are structurally and optically analogous to the focal conic domains formed spontaneously on the free surface of a cholesteric liquid crystal. The microstructure provides the bases for the morphogenesis as well as key insights for emulating the intricate optical response the exoskeleton of scarab beetles.

  17. Structural Origin of Circularly Polarized Iridescence in Jeweled Beetles

    NASA Astrophysics Data System (ADS)

    Sharma, Vivek; Crne, Matija; Park, Jung Ok; Srinivasarao, Mohan

    2009-07-01

    The iridescent metallic green beetle, Chrysina gloriosa, which selectively reflects left circularly polarized light, possesses an exoskeleton decorated by hexagonal cells (~10 μm) that coexist with pentagons and heptagons. The fraction of hexagons decreases with an increase in curvature. In bright field microscopy, each cell contains a bright yellow core, placed in a greenish cell with yellowish border, but the core disappears in dark field. With use of confocal microscopy, we observe that these cells consist of nearly concentric nested arcs that lie on the surface of a shallow cone. We infer that the patterns are structurally and optically analogous to the focal conic domains formed spontaneously on the free surface of a cholesteric liquid crystal. These textures provide the basis for the morphogenesis as well as key insights for emulating the intricate optical response of the exoskeleton of scarab beetles.

  18. Phylogeny of ambrosia beetle symbionts in the genus Raffaelea.

    PubMed

    Dreaden, Tyler J; Davis, John M; de Beer, Z Wilhelm; Ploetz, Randy C; Soltis, Pamela S; Wingfield, Michael J; Smith, Jason A

    2014-12-01

    The genus Raffaelea was established in 1965 when the type species, Raffaelea ambrosia, a symbiont of Platypus ambrosia beetles was described. Since then, many additional ambrosia beetle symbionts have been added to the genus, including the important tree pathogens Raffaelea quercivora, Raffaelea quercus-mongolicae, and Raffaelea lauricola, causal agents of Japanese and Korean oak wilt and laurel wilt, respectively. The discovery of new and the dispersal of described species of Raffaelea to new areas, where they can become invasive, presents challenges for diagnosticians as well as plant protection and quarantine efforts. In this paper, we present the first comprehensive multigene phylogenetic analysis of Raffaelea. As it is currently defined, the genus was found to not be monophyletic. On the basis of this work, Raffaelea sensu stricto is defined and the affinities of undescribed isolates are considered. PMID:25457944

  19. Bright-White Beetle Scales Optimise Multiple Scattering of Light

    PubMed Central

    Burresi, Matteo; Cortese, Lorenzo; Pattelli, Lorenzo; Kolle, Mathias; Vukusic, Peter; Wiersma, Diederik S.; Steiner, Ullrich; Vignolini, Silvia

    2014-01-01

    Whiteness arises from diffuse and broadband reflection of light typically achieved through optical scattering in randomly structured media. In contrast to structural colour due to coherent scattering, white appearance generally requires a relatively thick system comprising randomly positioned high refractive-index scattering centres. Here, we show that the exceptionally bright white appearance of Cyphochilus and Lepidiota stigma beetles arises from a remarkably optimised anisotropy of intra-scale chitin networks, which act as a dense scattering media. Using time-resolved measurements, we show that light propagating in the scales of the beetles undergoes pronounced multiple scattering that is associated with the lowest transport mean free path reported to date for low-refractive-index systems. Our light transport investigation unveil high level of optimisation that achieves high-brightness white in a thin low-mass-per-unit-area anisotropic disordered nanostructure. PMID:25123449

  20. Polyazamacrolides from ladybird beetles: ring-size selective oligomerization.

    PubMed

    Schroeder, F C; Smedley, S R; Gibbons, L K; Farmer, J J; Attygalle, A B; Eisner, T; Meinwald, J

    1998-11-10

    The pupal defensive secretion of the 24-pointed ladybird beetle, Subcoccinella vigintiquatuorpunctata, consists of a mixture of macrocyclic polyamines, dominated by the three dimeric, 30-membered macrocycles 11-13, derived from the two building blocks 11-(2-hydoxyethylamino)-5-tetradecenoic acid (9) and 11-(2-hydoxyethylamino)-5,8-tetradecadienoic acid (10). Smaller amounts of the four possible cyclic trimers of 9 and 10 were also detected, corresponding to 45-membered macrocycles. Structural assignments were based on NMR-spectroscopic investigations and HPLC-MS analyses. In addition, the all-S absolute configuration of the S. vigintiquatuorpunctata macrocycles was determined by comparison of derivatives of the natural material with enantiomerically pure synthetic samples. Comparing this alkaloid mixture with that of the pupal defensive secretion in related ladybird beetle species indicates that the degree of oligomerization of the 2-hydroxyethylamino carboxylic acid building blocks can be carefully controlled by the insects.

  1. Associational Patterns of Scavenger Beetles to Decomposition Stages.

    PubMed

    Zanetti, Noelia I; Visciarelli, Elena C; Centeno, Nestor D

    2015-07-01

    Beetles associated with carrion play an important role in recycling organic matter in an ecosystem. Four experiments on decomposition, one per season, were conducted in a semirural area in Bahía Blanca, Argentina. Melyridae are reported for the first time of forensic interest. Apart from adults and larvae of Scarabaeidae, thirteen species and two genera of other coleopteran families are new forensic records in Argentina. Diversity, abundance, and species composition of beetles showed differences between stages and seasons. Our results differed from other studies conducted in temperate regions. Four guilds and succession patterns were established in relation to decomposition stages and seasons. Dermestidae (necrophages) predominated in winter during the decomposition process; Staphylinidae (necrophiles) in Fresh and Bloat stages during spring, summer, and autumn; and Histeridae (necrophiles) and Cleridae (omnivores) in the following stages during those seasons. Finally, coleopteran activity, diversity and abundance, and decomposition rate change with biogeoclimatic characteristics, which is of significance in forensics.

  2. A checklist of stag beetles (Coleoptera: Scarabaeoidea: Lucanidae) from Iran.

    PubMed

    Bartolozzi, Luca; Ghahari, Hassan; Sprecher-Uebersax, Eva; Zilioli, Michele

    2014-11-26

    An updated checklist of the Lucanidae (Coleoptera) from Iran is given. New locality records are listed and some dubious distributional records are discussed. Dorcus vavrai Nonfried, 1905 is placed in synonymy with Dorcus peyronis Reiche and Saulcy, 1856 (new synonymy) The female of Lucanus xerxes Král, 2004 is described. A key for the identification of the Iranian stag beetle species is also provided and all the species are figured.

  3. Using malaise traps to sample ground beetles (Coleoptera. Carabidae)

    SciTech Connect

    Ulyshen, Michael D.; Hanula, James L.; Horn, Scott

    2012-04-02

    Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and trap-shy species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

  4. Using malaise traps to sample ground beetles (Coleoptera: Carabidae).

    SciTech Connect

    Ulyshen, Michael D., James L. Hanula, and Scott Horn

    2005-01-01

    Pitfall traps provide an easy and inexpensive way to sample ground-dwelling arthropods (Spence and Niemela 1994; Spence et al. 1997; Abildsnes and Tommeras 2000) and have been used exclusively in many studies of the abundance and diversity of ground beetles (Coleoptera: Carabidae). Despite the popularity of this trapping technique, pitfall traps have many disadvantages. For example, they often fail to collect both small (Spence and Niemela 1994) and trap-shy species (Benest 1989), eventually deplete the local carabid population (Digweed et al. 1995), require a species to be ground-dwelling in order to be captured (Liebherr and Mahar 1979), and produce different results depending on trap diameter and material, type of preservative used, and trap placement (Greenslade 1964; Luff 1975; Work et al. 2002). Further complications arise from seasonal patterns of movement among the beetles themselves (Maelfait and Desender 1990), as well as numerous climatic factors, differences in plant cover, and variable surface conditions (Adis 1979). Because of these limitations, pitfall trap data give an incomplete picture of the carabid community and should be interpreted carefully. Additional methods, such as use of Berlese funnels and litter washing (Spence and Niemela 1994), collection from lights (Usis and MacLean 1998), and deployment of flight intercept devices (Liebherr and Mahar 1979; Paarmann and Stork 1987), should be incorporated in surveys to better ascertain the species composition and relative numbers of ground beetles. Flight intercept devices, like pitfall traps, have the advantage of being easy to use and replicate, but their value to carabid surveys is largely unknown. Here we demonstrate the effectiveness of Malaise traps for sampling ground beetles in a bottomland hardwood forest.

  5. A checklist of stag beetles (Coleoptera: Scarabaeoidea: Lucanidae) from Iran.

    PubMed

    Bartolozzi, Luca; Ghahari, Hassan; Sprecher-Uebersax, Eva; Zilioli, Michele

    2014-01-01

    An updated checklist of the Lucanidae (Coleoptera) from Iran is given. New locality records are listed and some dubious distributional records are discussed. Dorcus vavrai Nonfried, 1905 is placed in synonymy with Dorcus peyronis Reiche and Saulcy, 1856 (new synonymy) The female of Lucanus xerxes Král, 2004 is described. A key for the identification of the Iranian stag beetle species is also provided and all the species are figured. PMID:25543941

  6. Protected by fumigants: beetle perfumes in antimicrobial defense.

    PubMed

    Gross, Jürgen; Schumacher, Kerstin; Schmidtberg, Henrike; Vilcinskas, Andreas

    2008-02-01

    Beetles share with other eukaryotes an innate immune system that mediates endogenous defense against pathogens. In addition, larvae of some taxa produce fluid exocrine secretions that contain antimicrobial compounds. In this paper, we provide evidence that larvae of the brassy willow leaf beetle Phratora vitellinae constitutively release volatile glandular secretions that combat pathogens in their microenvironment. We identified salicylaldehyde as the major component of their enveloping perfume cloud, which is emitted by furrow-shaped openings of larval glandular reservoirs and which inhibits in vitro the growth of the bacterial entomopathogen Bacillus thuringiensis. The suggested role of salicylaldehyde as a fumigant in exogenous antimicrobial defense was confirmed in vivo by its removal from glandular reservoirs. This resulted in an enhanced susceptibility of the larvae to infection with the fungal entomopathogens Beauveria bassiana and Metarhizium anisopliae. Consequently, we established the hypothesis that antimicrobial defense in beetles can be expanded beyond innate immunity to include external disinfection of their microenvironment, and we report for the first time the contribution of fumigants to antimicrobial defense in animals.

  7. DETECTION OF DRUGSTORE BEETLES IN 9975 PACKAGES USING ACOUSTIC EMISSIONS

    SciTech Connect

    Shull, D.

    2013-03-04

    This report documents the initial feasibility tests performed using a commercial acoustic emission instrument for the purpose of detecting beetles in Department of Energy 9975 shipping packages. The device selected for this testing was a commercial handheld instrument and probe developed for the detection of termites, weevils, beetles and other insect infestations in wooden structures, trees, plants and soil. The results of two rounds of testing are presented. The first tests were performed by the vendor using only the hand-held instrument’s indications and real-time operator analysis of the audio signal content. The second tests included hands-free positioning of the instrument probe and post-collection analysis of the recorded audio signal content including audio background comparisons. The test results indicate that the system is promising for detecting the presence of drugstore beetles, however, additional work would be needed to improve the ease of detection and to automate the signal processing to eliminate the need for human interpretation. Mechanisms for hands-free positioning of the probe and audio background discrimination are also necessary for reliable detection and to reduce potential operator dose in radiation environments.

  8. Monoterpene emissions from bark beetle infested Engelmann spruce trees

    NASA Astrophysics Data System (ADS)

    Amin, Hardik S.; Russo, Rachel S.; Sive, Barkley; Richard Hoebeke, E.; Dodson, Craig; McCubbin, Ian B.; Gannet Hallar, A.; Huff Hartz, Kara E.

    2013-06-01

    Bark beetle infestation impacts the health of coniferous forests, which are an important source of volatile organic compounds (VOCs) to the atmosphere. The types and amounts of VOCs emitted from forests can influence secondary organic aerosol (SOA) formation and impact overall air quality. In this initial work, the impact of bark beetle infestation on SOA precursors from Engelmann spruce is assessed. The VOCs emitted from the trunk of infested and healthy spruce trees were sampled using both sorbent traps and evacuated canisters that were analyzed by gas chromatography/mass spectroscopy. The samples from the infested spruce tree suggest a nine-fold enhancement in the total VOC emissions. The dominant VOCs in the infested spruce trees were 3-carene, β-pinene, and α-pinene. The increase observed in VOCs sampled at the trunk of the infested spruce was consistent with increases observed at infested lodgepole pine trunks. However, the types and amounts of VOCs emitted from Engelmann spruce and lodgepole pine are different, which suggests that additional measures of VOC emissions are needed to characterize the impact of bark beetle infestation on VOC emissions and SOA precursors.

  9. Coffee Berry Borer Joins Bark Beetles in Coffee Klatch

    PubMed Central

    Jaramillo, Juliana; Torto, Baldwyn; Mwenda, Dickson; Troeger, Armin; Borgemeister, Christian; Poehling, Hans-Michael; Francke, Wittko

    2013-01-01

    Unanswered key questions in bark beetle-plant interactions concern host finding in species attacking angiosperms in tropical zones and whether management strategies based on chemical signaling used for their conifer-attacking temperate relatives may also be applied in the tropics. We hypothesized that there should be a common link in chemical signaling mediating host location by these Scolytids. Using laboratory behavioral assays and chemical analysis we demonstrate that the yellow-orange exocarp stage of coffee berries, which attracts the coffee berry borer, releases relatively high amounts of volatiles including conophthorin, chalcogran, frontalin and sulcatone that are typically associated with Scolytinae chemical ecology. The green stage of the berry produces a much less complex bouquet containing small amounts of conophthorin but no other compounds known as bark beetle semiochemicals. In behavioral assays, the coffee berry borer was attracted to the spiroacetals conophthorin and chalcogran, but avoided the monoterpenes verbenone and α-pinene, demonstrating that, as in their conifer-attacking relatives in temperate zones, the use of host and non-host volatiles is also critical in host finding by tropical species. We speculate that microorganisms formed a common basis for the establishment of crucial chemical signals comprising inter- and intraspecific communication systems in both temperate- and tropical-occurring bark beetles attacking gymnosperms and angiosperms. PMID:24073204

  10. Antibiotic-producing bacteria from stag beetle mycangia.

    PubMed

    Miyashita, Atsushi; Hirai, Yuuki; Sekimizu, Kazuhisa; Kaito, Chikara

    2015-02-01

    The search for new antibiotics or antifungal agents is crucial for the chemotherapies of infectious diseases. The limited resource of soil bacteria makes it difficult to discover such new drug candidate. We, therefore, focused on another bacterial resource than soil bacteria, the microbial flora of insect species. In the present study, we isolated 40 strains of bacteria and fungi from the mycangia of three species of stag beetle, Dorcus hopei binodulosus, Dorcus rectus, and Dorcus titanus pilifer. We identified those species with their ribosomal DNA sequences, and revealed that Klebsiella spp. are the most frequent symbiont in the stag beetle mycangia. We examined whether these microorganisms produce antibiotics against a Gram-negative bacterium, Escherichia coli, a Gram-positive bacterium, Staphylococcus aureus, or a fungus, Cryptococcus neoformans. Culture supernatants from 33, 29, or 18 strains showed antimicrobial activity against E. coli, S. aureus, or C. neoformans, respectively. These findings suggest that bacteria present in the mycangia of stag beetles are useful resources for screening novel antibiotics. PMID:25639488

  11. The relative abundance of mountain pine beetle fungal associates through the beetle life cycle in pine trees.

    PubMed

    Khadempour, Lily; LeMay, Valerie; Jack, David; Bohlmann, Jörg; Breuil, Colette

    2012-11-01

    The mountain pine beetle (MPB) is a native bark beetle of western North America that attacks pine tree species, particularly lodgepole pine. It is closely associated with the ophiostomatoid ascomycetes Grosmannia clavigera, Leptographium longiclavatum, Ophiostoma montium, and Ceratocystiopsis sp.1, with which it is symbiotically associated. To develop a better understanding of interactions between beetles, fungi, and host trees, we used target-specific DNA primers with qPCR to assess the changes in fungal associate abundance over the stages of the MPB life cycle that occur in galleries under the bark of pine trees. Multivariate analysis of covariance identified statistically significant changes in the relative abundance of the fungi over the life cycle of the MPB. Univariate analysis of covariance identified a statistically significant increase in the abundance of Ceratocystiopsis sp.1 through the beetle life cycle, and pair-wise analysis showed that this increase occurs after the larval stage. In contrast, the abundance of O. montium and Leptographium species (G. clavigera, L. longiclavatum) did not change significantly through the MPB life cycle. From these results, the only fungus showing a significant increase in relative abundance has not been formally described and has been largely ignored by other MPB studies. Although our results were from only one site, in previous studies we have shown that the fungi described were all present in at least ten sites in British Columbia. We suggest that the role of Ceratocystiopsis sp.1 in the MPB system should be explored, particularly its potential as a source of nutrients for teneral adults.

  12. Infection of Tribolium beetles with a tapeworm: variation in susceptibility within and between beetle species and among genetic strains.

    PubMed

    Yan, G; Norman, S

    1995-02-01

    Host susceptibility and resistance to parasites are often hypothesized to be genetically variable traits. We tested 2 species of Tribolium flour beetles for among-strain variation in susceptibility to the rat tapeworm Hymenolepis diminuta. Twelve genetic strains of Tribolium confusum and 11 strains of Tribolium castaneum were examined. We found T. castaneum was more susceptible to the tapeworm than T. confusum. There was significant among-strain and between-sex variation for both beetle species in infection intensity and prevalence. Among-vial variation was marginally significant. These results add to evidence that host susceptibility to a parasite is a genetically variable trait. We view these results as important findings for understanding natural selection on host-parasite interactions. Traits that are genetically variable can respond to natural selection. Thus, if a beetle's susceptibility to the tapeworm is correlated with fitness and heritable, susceptibility can evolve. Susceptibility is likely to be pleiotropic and have important consequences on issues ranging from parasite transmission to host species interactions and community structure.

  13. Jumping mechanisms and performance in beetles. I. Flea beetles (Coleoptera: Chrysomelidae: Alticini).

    PubMed

    Nadein, Konstantin; Betz, Oliver

    2016-07-01

    The present study analyses the anatomy, mechanics and functional morphology of the jumping apparatus, the performance and the kinematics of the natural jump of flea beetles (Coleoptera: Chrysomelidae: Galerucinae: Alticini). The kinematic parameters of the initial phase of the jump were calculated for five species from five genera (average values from minimum to maximum): acceleration 0.91-2.25 (×10(3)) m s(-2), velocity 1.48-2.80 m s(-1), time to take-off 1.35-2.25 ms, kinetic energy 2.43-16.5 µJ, G: -force 93-230. The jumping apparatus is localized in the hind legs and formed by the femur, tibia, femoro-tibial joint, modified metafemoral extensor tendon, extensor ligament, tibial flexor sclerite, and extensor and flexor muscles. The primary role of the metafemoral extensor tendon is seen in the formation of an increased attachment site for the extensor muscles. The rubber-like protein resilin was detected in the extensor ligament, i.e. a short, elastic element connecting the extensor tendon with the tibial base. The calculated specific joint power (max. 0.714 W g(-1)) of the femoro-tibial joint during the jumping movement and the fast full extension of the hind tibia (1-3 ms) suggest that jumping is performed via a catapult mechanism releasing energy that has beforehand been stored in the extensor ligament during its stretching by the extensor muscles. In addition, the morphology of the femoro-tibial joint suggests that the co-contraction of the flexor and the extensor muscles in the femur of the jumping leg is involved in this process. PMID:27385755

  14. Jumping mechanisms and performance in beetles. I. Flea beetles (Coleoptera: Chrysomelidae: Alticini).

    PubMed

    Nadein, Konstantin; Betz, Oliver

    2016-07-01

    The present study analyses the anatomy, mechanics and functional morphology of the jumping apparatus, the performance and the kinematics of the natural jump of flea beetles (Coleoptera: Chrysomelidae: Galerucinae: Alticini). The kinematic parameters of the initial phase of the jump were calculated for five species from five genera (average values from minimum to maximum): acceleration 0.91-2.25 (×10(3)) m s(-2), velocity 1.48-2.80 m s(-1), time to take-off 1.35-2.25 ms, kinetic energy 2.43-16.5 µJ, G: -force 93-230. The jumping apparatus is localized in the hind legs and formed by the femur, tibia, femoro-tibial joint, modified metafemoral extensor tendon, extensor ligament, tibial flexor sclerite, and extensor and flexor muscles. The primary role of the metafemoral extensor tendon is seen in the formation of an increased attachment site for the extensor muscles. The rubber-like protein resilin was detected in the extensor ligament, i.e. a short, elastic element connecting the extensor tendon with the tibial base. The calculated specific joint power (max. 0.714 W g(-1)) of the femoro-tibial joint during the jumping movement and the fast full extension of the hind tibia (1-3 ms) suggest that jumping is performed via a catapult mechanism releasing energy that has beforehand been stored in the extensor ligament during its stretching by the extensor muscles. In addition, the morphology of the femoro-tibial joint suggests that the co-contraction of the flexor and the extensor muscles in the femur of the jumping leg is involved in this process.

  15. Diversity abundance and seasonality of ambrosia beetles (Coleoptera: curculionida) in Southern Mississippi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A survey was undertaken in 2010 to assess the makeup of the ambrosia beetle (Coleoptera: Curculionidae) community at two research sites in South Mississippi. Inexpensive beetle traps were constructed and fitted with ethanol lures, with bi-weekly collections made from March through November. The gr...

  16. Ambrosia beetle (Coleoptera: Curculionidae: Scolytinae) captures using colored traps in southeast Tennessee and south Mississippi

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ambrosia beetles have become a major problem for nursery production, with controls centered around an accurate monitoring program. While the use of semiochemicals by ambrosia beetles is well understood, their potential use of visual cues including color remains relatively understudied. Field tests...

  17. Male-Produced Aggregation Pheromone of the Lesser Mealworm Beetle Alphitobius diaperinus (Coleoptera: Tenebrionidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The lesser mealworm beetle Alphitobius diaperinus (Panzer) is a widespread, serious pest in poultry production facilities and is difficult to control by conventional means. Although pheromone-based tools have become useful in the management of other beetle pests, no pheromone was known for A. diape...

  18. Darkling Beetles as a Potential Transmission Source of Salmonella in Broiler Flocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The adult and larval darkling beetles (Alphitobius diaperinus Panzer) are common insect pests of commercial broiler operations. High populations of darkling beetles in commercial broiler operations can have a negative impact finanacially due to structural and insulation damage within the house, red...

  19. Marking small hive beetles with thoracic notching: Effects on longevity, flight ability and fecundity.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We tested two marking techniques for adult small hive beetles (SHB): dusting and thoracic notching. The use of blue and red chalk dusts to mark beetles was not persistent and caused early death of SHB with an average survival of 52.6 ± 23.8 and 13.9 ± 7.3 days, respectively. In contrast, notched bee...

  20. BeetleBase in 2010: Revisions to Provide Comprehensive Genomic Information for Tribolium castaneum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BeetleBase (http://www.beetlebase.org) has been updated to provide more comprehensive genomic information for the red flour beetle Tribolium castaneum. The database contains genomic sequence scaffolds mapped to 10 linkage groups (genome assembly release Tcas_3.0), genetic linkage maps, the official ...

  1. Control of Chinese rose beetle (Coleoptera: Scarabaeidae) through the use of solar-powered nighttime illumination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chinese rose beetle, Adoretus sinicus (Burmeister), a scarab beetle found in Asia and the Pacific Islands, was first reported in Hawaii in 1891. Adults feed at night on leaves of a wide range of plant species, including many that are economically important. Aggregate feeding can stunt or even kill ...

  2. Effectiveness of hand removal for small-scale management of Japanese beetles (Coleoptera: Scarabaeidae).

    PubMed

    Switzer, Paul V; Cumming, Ryan M

    2014-02-01

    Hand removal is often recommended as a method for small-scale control of Japanese beetles (Popillia japonica Newman). In this study, we investigated the effectiveness of daily hand removal for controlling damage by Japanese beetles on grape plants. We also investigated whether the timing of the removal (at 0800, 1400, or 1900 hours, or at all 3 periods) influenced the effectiveness of the technique. We found that hand removal significantly lowered the number of beetles on, and consequently the damage to, grape plants relative to nonremoval controls. Of the single removal treatments, removal of beetles at 1900 hours was most effective, with results similar to removing beetles three times per day. The majority of beetles removed from plants during the experiment were female, a pattern that matches our understanding of aggregation formation behavior in the species, and which may serve to enhance the benefits of hand removal. Hand removal seems to work by decreasing the number of feeding beetles, which in turn reduces the release of aggregation kairomones from the plant, and subsequently decreases the attractiveness of the plant to future beetles.

  3. Monitoring diapause development in the Colorado potato beetle, Leptinotarsa decemlineata, under field conditions using molecular biomarkers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A multiplex PCR protocol was developed using five diapause-regulated genes to monitor diapause development of the Colorado potato beetle under field conditions. A total of 870 beetles from the Red River Valley of North Dakota and Minnesota, USA, were screened for three consecutive years. Out of the ...

  4. Factors influencing bark beetle outbreaks after forest fires on the Iberian Peninsula.

    PubMed

    Lombardero, María J; Ayres, Matthew P

    2011-10-01

    Fires are among the most globally important disturbances in forest ecosystems. Forest fires can be followed by bark beetle outbreaks. Therefore, the dynamic interactions between bark beetle outbreaks and fire appear to be of general importance in coniferous forests throughout the world. We tested three hypotheses of how forest fires in pine ecosystems (Pinus pinaster Alton and P. radiata D. Don) in Spain could alter the population dynamics of bark beetles and influence the probability of further disturbance from beetle outbreaks: fire could affect the antiherbivore resin defenses of trees, change their nutritional suitability, or affect top-down controls on herbivore populations. P. radiata defenses decreased immediately after fire, but trees with little crown damage soon recovered with defenses higher than before. Fire either reduced or did not affect nutritional quality of phloem and either reduced or had no effect on the abundance, diversity, and relative biomass of natural enemies. After fire, bark beetle abundance increased via rapid aggregation of reproductive adults on scorched trees. However, our results indicate that for populations to increase to an outbreak situation, colonizing beetles must initiate attacks before tree resin defenses recover, host trees must retain enough undamaged phloem to facilitate larval development, and natural enemies should be sufficiently rare to permit high beetle recruitment into the next generation. Coincidence of these circumstances may promote the possibility of beetle populations escaping to outbreak levels.

  5. Small hive beetles, honeybees, yeast and plants: evolution of an insect pest

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Small hive beetle, Aethina tumida, is seemingly an anomaly among Nitidulids because it thrives in honeybee hives feeding on pollen and bee brood. Attraction to bee hives is mediated by the Honeybee alarm pheromone. We have discovered that when feeding on pollen resources in bee hives the beetl...

  6. Agricultural Land Use Determines the Trait Composition of Ground Beetle Communities.

    PubMed

    Hanson, Helena I; Palmu, Erkki; Birkhofer, Klaus; Smith, Henrik G; Hedlund, Katarina

    2016-01-01

    In order to improve biological control of agricultural pests, it is fundamental to understand which factors influence the composition of natural enemies in agricultural landscapes. In this study, we aimed to understand how agricultural land use affects a number of different traits in ground beetle communities to better predict potential consequences of land-use change for ecosystem functioning. We studied ground beetles in fields with different agricultural land use ranging from frequently managed sugar beet fields, winter wheat fields to less intensively managed grasslands. The ground beetles were collected in emergence tents that catch individuals overwintering locally in different life stages and with pitfall traps that catch individuals that could have a local origin or may have dispersed into the field. Community weighted mean values for ground beetle traits such as body size, flight ability and feeding preference were estimated for each land-use type and sampling method. In fields with high land-use intensity the average body length of emerging ground beetle communities was lower than in the grasslands while the average body length of actively moving communities did not differ between the land-use types. The proportion of ground beetles with good flight ability or a carnivorous diet was higher in the crop fields as compared to the grasslands. Our study highlights that increasing management intensity reduces the average body size of emerging ground beetles and the proportion of mixed feeders. Our results also suggest that the dispersal ability of ground beetles enables them to compensate for local management intensities.

  7. Genetics and characteristics of a pigmentation defective laboratory strain of the lady beetle, Coleomegilla maculata

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beetles in the family Coccinellidae, commonly known as ladybugs, lady beetles, or ladybirds, are easily identifiable and popular beneficial insects. The species complex Coleomegilla maculata is commonly found in North American agroecosystems and widespread on the North American continent. It is impo...

  8. Pattern formation in a model for mountain pine beetle dispersal: linking model predictions to data.

    PubMed

    Strohm, S; Tyson, R C; Powell, J A

    2013-10-01

    Pattern formation occurs in a wide range of biological systems. This pattern formation can occur in mathematical models because of diffusion-driven instability or due to the interaction between reaction, diffusion, and chemotaxis. In this paper, we investigate the spatial pattern formation of attack clusters in a system for Mountain Pine Beetle. The pattern formation (aggregation) of the Mountain Pine Beetle in order to attack susceptible trees is crucial for their survival and reproduction. We use a reaction-diffusion equation with chemotaxis to model the interaction between Mountain Pine Beetle, Mountain Pine Beetle pheromones, and susceptible trees. Mathematical analysis is utilized to discover the spacing in-between beetle attacks on the susceptible landscape. The model predictions are verified by analysing aerial detection survey data of Mountain Pine Beetle Attack from the Sawtooth National Recreation Area. We find that the distance between Mountain Pine Beetle attack clusters predicted by our model closely corresponds to the observed attack data in the Sawtooth National Recreation Area. These results clarify the spatial mechanisms controlling the transition from incipient to epidemic populations and may lead to control measures which protect forests from Mountain Pine Beetle outbreak.

  9. 76 FR 48120 - Black Hills National Forest, Custer, SD-Mountain Pine Beetle Response Project

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-08

    ... Forest Service Black Hills National Forest, Custer, SD--Mountain Pine Beetle Response Project AGENCY...: This project proposes to treat areas newly infested by mountain pine beetles on approximately 325,000...-rocky-mountain-black-hills@fs.fed.us , with ``MPB Response Project'' in the subject line....

  10. Seasonal and spatial dispersal patterns of ambrosia beetles (Coleoptera: curculionidae) from forest habitats into production nurseries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Exotic ambrosia beetles (Coleoptera: Curculionidae) are important pests of tree nurseries. While they are known to migrate in early spring from peripheral forested areas into nurseries, there are few data to show how far ambrosia beetles will fly to infest new host trees, or whether a mass trapping...

  11. Inquiry-based Investigation in Biology Laboratories: Does Neem Provide Bioprotection against Bean Beetles?

    ERIC Educational Resources Information Center

    Pearce, Amy R.; Sale, Amanda Lovelace; Srivatsan, Malathi; Beck, Christopher W.; Blumer, Lawrence S.; Grippo, Anne A.

    2013-01-01

    We developed an inquiry-based biology laboratory exercise in which undergraduate students designed experiments addressing whether material from the neem tree ("Azadirachta indica") altered bean beetle ("Callosobruchus maculatus") movements and oviposition. Students were introduced to the bean beetle life cycle, experimental…

  12. Longevity and viability of Taenia solium eggs in the digestive system of the beetle Ammophorus rubripes.

    PubMed

    Gomez-Puerta, Luis Antonio; Lopez-Urbina, Maria Teresa; Garcia, Hector Hugo; Gonzalez, Armando Emiliano

    2014-03-01

    The present study evaluated the capacity of Ammophorus rubripes beetles to carry Taenia solium eggs, in terms of duration and viab