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Sample records for bark beetle ips

  1. Host-tree monoterpenes and biosynthesis of aggregation pheromones in the bark beetle ips paraconfusus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the 1970-80s, vapors of the common conifer tree monoterpenes, myrcene and a-pinene, were shown to serve as precursors of ipsenol, ipsdienol and cis-verbenol, aggregation pheromone components of Ips paraconfusus. A paradigm developed that Ips bark beetles utilize pre-formed monoterpene precursors ...

  2. Effect of bark beetle (Ips typographus L.) attack on bark VOC emissions of Norway spruce (Picea abies Karst.) trees

    NASA Astrophysics Data System (ADS)

    Ghimire, Rajendra P.; Kivimäenpää, Minna; Blomqvist, Minna; Holopainen, Toini; Lyytikäinen-Saarenmaa, Päivi; Holopainen, Jarmo K.

    2016-02-01

    Climate warming driven storms are evident causes for an outbreak of the European spruce bark beetle (Ips typographus L.) resulting in the serious destruction of mature Norway spruce (Picea abies Karst.) forests in northern Europe. Conifer species are major sources of biogenic volatile organic compounds (BVOCs) in the boreal zone. Climate relevant BVOC emissions are expected to increase when conifer trees defend against bark beetle attack by monoterpene (MT)-rich resin flow. In this study, BVOC emission rates from the bark surface of beetle-attacked and non-attacked spruce trees were measured from two outbreak areas, Iitti and Lahti in southern Finland, and from one control site at Kuopio in central Finland. Beetle attack increased emissions of total MTs 20-fold at Iitti compared to Kuopio, but decreased the emissions of several sesquiterpenes (SQTs) at Iitti. At the Lahti site, the emission rate of α-pinene was positively correlated with mean trap catch of bark beetles. The responsive individual MTs were tricyclene, α-pinene, camphene, myrcene, limonene, 1,8-cineole and bornyl acetate in both of the outbreak areas. Our results suggest that bark beetle outbreaks affect local BVOC emissions from conifer forests dominated by Norway spruce. Therefore, the impacts of insect outbreaks are worth of consideration to global BVOC emission models.

  3. Conifer stored resources and resistance to a fungus associated with the spruce bark beetle Ips typographus.

    PubMed

    Lahr, Eleanor C; Krokene, Paal

    2013-01-01

    Bark beetles and associated fungi are among the greatest natural threats to conifers worldwide. Conifers have potent defenses, but resistance to beetles and fungal pathogens may be reduced if tree stored resources are consumed by fungi rather than used for tree defense. Here, we assessed the relationship between tree stored resources and resistance to Ceratocystis polonica, a phytopathogenic fungus vectored by the spruce bark beetle Ips typographus. We measured phloem and sapwood nitrogen, non-structural carbohydrates (NSC), and lipids before and after trees were attacked by I. typographus (vectoring C. polonica) or artificially inoculated with C. polonica alone. Tree resistance was assessed by measuring phloem lesions and the proportion of necrotic phloem around the tree's circumference following attack or inoculation. While initial resource concentrations were unrelated to tree resistance to C. polonica, over time, phloem NSC and sapwood lipids declined in the trees inoculated with C. polonica. Greater resource declines correlated with less resistant trees (trees with larger lesions or more necrotic phloem), suggesting that resource depletion may be caused by fungal consumption rather than tree resistance. Ips typographus may then benefit indirectly from reduced tree defenses caused by fungal resource uptake. Our research on tree stored resources represents a novel way of understanding bark beetle-fungal-conifer interactions.

  4. Host resistance elicited by methyl jasmonate reduces emission of aggregation pheromones by the spruce bark beetle, Ips typographus.

    PubMed

    Zhao, Tao; Borg-Karlson, Anna-Karin; Erbilgin, Nadir; Krokene, Paal

    2011-11-01

    We treated Norway spruce (Picea abies) stems with methyl jasmonate (MeJA) to determine possible quantitative and qualitative effects of induced tree defenses on pheromone emission by the spruce bark beetle Ips typographus. We measured the amounts of 2-methyl-3-buten-2-ol and (S)-cis-verbenol, the two main components of the beetle's aggregation pheromone, released from beetle entrance holes, along with phloem terpene content and beetle performance in MeJA-treated and untreated Norway spruce logs. As expected, phloem terpene levels were higher and beetle tunnel length was shorter (an indication of poor performance) in MeJA-treated logs relative to untreated logs. Parallel to the higher phloem terpene content and poorer beetle performance, beetles in MeJA-treated logs released significantly less 2-methyl-3-buten-2-ol and (S)-cis-verbenol, and the ratio between the two pheromone components was significantly altered. These results suggest that host resistance elicited by MeJA application reduces pheromone emission by I. typographus and alters the critical ratio between the two main pheromone components needed to elicit aggregation. The results also provide a mechanistic explanation for the reduced performance and attractivity observed in earlier studies when bark beetles colonize trees with elicited host defenses, and extend our understanding of the ecological functions of conifer resistance against bark beetles.

  5. Fungi vectored by the bark beetle Ips typographus following hibernation under the bark of standing trees and in the forest litter.

    PubMed

    Persson, Ylva; Vasaitis, Rimvydas; Långström, Bo; Ohrn, Petter; Ihrmark, Katarina; Stenlid, Jan

    2009-10-01

    The bark beetle Ips typographus has different hibernation environments, under the bark of standing trees or in the forest litter, which is likely to affect the beetle-associated fungal flora. We isolated fungi from beetles, standing I. typographus-attacked trees, and forest litter below the attacked trees. Fungal identification was done using cultural and molecular methods. The results of the two methods in detecting fungal species were compared. Fungal communities associated with I. typographus differed considerably depending on the hibernation environment. In addition to seven taxa of known ophiostomoid I. typographus-associated fungi, we detected 18 ascomycetes and anamorphic fungi, five wood-decaying basidomycetes, 11 yeasts, and four zygomycetes. Of those, 14 fungal taxa were detected exclusively from beetles that hibernated under bark, and six taxa were detected exclusively from beetles hibernating in forest litter. The spruce pathogen, Ceratocystis polonica, was detected occasionally in bark, while another spruce pathogen, Grosmannia europhioides, was detected more often from beetles hibernating under the bark as compared to litter. The identification method had a significant impact on which taxa were detected. Rapidly growing fungal taxa, e.g. Penicillium, Trichoderma, and Ophiostoma, dominated pure culture isolations; while yeasts dominated the communities detected using molecular methods. The study also demonstrated low frequencies of tree pathogenic fungi carried by I. typographus during its outbreaks and that the beetle does not require them to successfully attack and kill trees.

  6. The bark beetle, Ips grandicollis, disrupts biological control of the woodwasp, Sirex noctilio, via fungal symbiont interactions.

    PubMed

    Yousuf, Fazila; Gurr, Geoff M; Carnegie, Angus J; Bedding, Robin A; Bashford, Richard; Gitau, Catherine W; Nicol, Helen I

    2014-04-01

    The corticoid fungus, Amylostereum areolatum, is deposited in pine trees by the woodwasp, Sirex noctilio, at the time of oviposition. This fungus is essential in S. noctilio larval growth and it is also a food source for Beddingia siricidicola, the nematode used for S. noctilio biological control. In recent years, the historically successful biological control programme has been disrupted in Australia by the bark beetle, Ips grandicollis. This study investigated whether the mechanism of this disruption involves a fungus, Ophiostoma ips, which I. grandicollis introduces into trees. In artificial and wood media, A. areolatum was unable to grow in areas occupied by O. ips. The latter fungus was faster growing, especially at 25 °C rather than 20 °C. Larval galleries of S. noctilio in field-collected samples were strongly associated with wood infested by A. areolatum and absent from areas affected by O. ips. The nematode failed to survive and reproduce on O. ips as it can on A. areolatum. Competitive interactions between O. ips and A. areolatum within the trap trees are demonstrated to be key factors in the negative effect of I. grandicollis on S. noctilio biological control programmes.

  7. Non-host volatile blend optimization for forest protection against the European spruce bark beetle, Ips typographus.

    PubMed

    Unelius, C Rikard; Schiebe, Christian; Bohman, Björn; Andersson, Martin N; Schlyter, Fredrik

    2014-01-01

    Conifer feeding bark beetles (Coleoptera, Curculionidae, Scolytinae) pose a serious economic threat to forest production. Volatiles released by non-host angiosperm plants (so called non-host volatiles, NHV) have been shown to reduce the risk of attack by many bark beetle species, including the European spruce bark beetle, Ips typographus. However, the most active blend for I. typographus, containing three green leaf volatiles (GLVs) in addition to the key compounds trans-conophthorin (tC) and verbenone, has been considered too expensive for use in large-scale management. To lower the cost and improve the applicability of NHV, we aim to simplify the blend without compromising its anti-attractant potency. Since the key compound tC is expensive in pure form, we also tested a crude version: technical grade trans-conophthorin (T-tC). In another attempt to find a more cost effective substitute for tC, we evaluated a more readily synthesized analog: dehydro-conophthorin (DHC). Our results showed that 1-hexanol alone could replace the three-component GLV blend containing 1-hexanol, (3Z)-hexen-1-ol, and (2E)-hexen-1-ol. Furthermore, the release rate of tC could be reduced from 5 mg/day to 0.5 mg/day in a blend with 1-hexanol and (-)-verbenone without compromising the anti-attractant activity. We further show that T-tC was comparable with tC, whereas DHC was a less effective anti-attractant. DHC also elicited weaker physiological responses in the tC-responding olfactory receptor neuron class, providing a likely mechanistic explanation for its weaker anti-attractive effect. Our results suggest a blend consisting of (-)-verbenone, 1-hexanol and technical trans-conophthorin as a cost-efficient anti-attractant for forest protection against I. typographus.

  8. De novo biosynthesis of the aggregation pheromone components ipsenol and ipsdienol by the pine bark beetles Ips paraconfusus Lanier and Ips pini (Say) (Coleoptera: Scolytidae).

    PubMed Central

    Seybold, S J; Quilici, D R; Tillman, J A; Vanderwel, D; Wood, D L; Blomquist, G J

    1995-01-01

    The California five-spined ips, Ips paraconfusus Lanier, produces the myrcene-derived acyclic monoterpene alcohols ipsenol (2-methyl-6-methylene-7-octen-4-ol) and ipsdienol (2-methyl-6-methylene-2,7-octadien-4-ol) as components of its aggregation pheromone. The pine engraver beetle, Ips pini (Say), produces only ipsdienol. Previous studies have shown that myrcene, a monoterpene in the pines colonized by these beetles, is a direct precursor to these pheromone components. In vivo radiolabeling studies reported here showed that male I. paraconfusus incorporated [1-14C]acetate into ipsenol, ipsdienol, and amitinol (trans-2-methyl-6-methylene-3,7-octadien-2-ol), while male I. pini incorporated [1-14C]acetate into ipsdienol and amitinol. Females of these species produced neither labeled nor unlabeled pheromone components. The purified radiolabeled monoterpene alcohols from-males were identified by comparison of their HPLC and GC retention times with those of unlabeled standards. HPLC-purified fractions containing the individual radiolabeled components were analyzed by GC-MS and were shown to include only the pure alcohols. To further confirm that ipsdienol and ipsenol were radiolabeled, diastereomeric ester derivatives of the isolated alcohols were synthesized and analyzed by HPLC and GC-MS. After derivatization of the radiolabeled alcohols, the HPLC analysis demonstrated expected shifts in retention times with conservation of naturally occurring stereochemistry. The results provide direct evidence for de novo biosynthesis of ipsenol, ipsdienol, and amitinol by bark beetles. PMID:11607576

  9. High substrate specificity of ipsdienol dehydrogenase (IDOLDH), a short-chain dehydrogenase from Ips pini bark beetles.

    PubMed

    Figueroa-Teran, Rubi; Pak, Heidi; Blomquist, Gary J; Tittiger, Claus

    2016-09-01

    Ips spp. bark beetles use ipsdienol, ipsenol, ipsdienone and ipsenone as aggregation pheromone components and pheromone precursors. For Ips pini, the short-chain oxidoreductase ipsdienol dehydrogenase (IDOLDH) converts (-)-ipsdienol to ipsdienone, and thus likely plays a role in determining pheromone composition. In order to further understand the role of IDOLDH in pheromone biosynthesis, we compared IDOLDH to its nearest functionally characterized ortholog with a solved structure: human L-3-hydroxyacyl-CoA dehydrogenase type II/ amyloid-β binding alcohol dehydrogenase (hHADH II/ABAD), and conducted functional assays of recombinant IDOLDH to determine substrate and product ranges and structural characteristics. Although IDOLDH and hHADH II/ABAD had only 35% sequence identity, their predicted tertiary structures had high identity. We found IDOLDH is a functional homo-tetramer. In addition to oxidizing (-)-ipsdienol, IDOLDH readily converted racemic ipsenol to ipsenone, and stereo-specifically reduced both ketones to their corresponding (-)-alcohols. The (+)-enantiomers were never observed as products. Assays with various substrate analogs showed IDOLDH had high substrate specificity for (-)-ipsdienol, ipsenol, ipsenone and ipsdienone, supporting that IDOLDH functions as a pheromone-biosynthetic enzyme. These results suggest that different IDOLDH orthologs and or activity levels contribute to differences in Ips spp. pheromone composition.

  10. Pheromone production in bark beetles.

    PubMed

    Blomquist, Gary J; Figueroa-Teran, Rubi; Aw, Mory; Song, Minmin; Gorzalski, Andrew; Abbott, Nicole L; Chang, Eric; Tittiger, Claus

    2010-10-01

    The first aggregation pheromone components from bark beetles were identified in 1966 as a mixture of ipsdienol, ipsenol and verbenol. Since then, a number of additional components have been identified as both aggregation and anti-aggregation pheromones, with many of them being monoterpenoids or derived from monoterpenoids. The structural similarity between the major pheromone components of bark beetles and the monoterpenes found in the host trees, along with the association of monoterpenoid production with plant tissue, led to the paradigm that most if not all bark beetle pheromone components were derived from host tree precursors, often with a simple hydroxylation producing the pheromone. In the 1990 s there was a paradigm shift as evidence for de novo biosynthesis of pheromone components began to accumulate, and it is now recognized that most bark beetle monoterpenoid aggregation pheromone components are biosynthesized de novo. The bark beetle aggregation pheromones are released from the frass, which is consistent with the isoprenoid aggregation pheromones, including ipsdienol, ipsenol and frontalin, being produced in midgut tissue. It appears that exo-brevocomin is produced de novo in fat body tissue, and that verbenol, verbenone and verbenene are produced from dietary α-pinene in fat body tissue. Combined biochemical, molecular and functional genomics studies in Ips pini yielded the discovery and characterization of the enzymes that convert mevalonate pathway intermediates to pheromone components, including a novel bifunctional geranyl diphosphate synthase/myrcene synthase, a cytochrome P450 that hydroxylates myrcene to ipsdienol, and an oxidoreductase that interconverts ipsdienol and ipsdienone to achieve the appropriate stereochemistry of ipsdienol for pheromonal activity. Furthermore, the regulation of these genes and their corresponding enzymes proved complex and diverse in different species. Mevalonate pathway genes in pheromone producing male I. pini

  11. 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

  12. 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

  13. Biological differences reflect host preference in two parasitoids attacking the bark beetle Ips typographus (Coleoptera: Scolytidae) in Belgium.

    PubMed

    Hougardy, E; Grégoire, J-C

    2004-08-01

    The basic reproductive biology of two ectoparasitoids developing on the late larval instars of the scolytid Ips typographus Linnaeus, a pest of spruce forests in Eurasia, was studied with the purpose of explaining which biological features allow the two species to share the same host. The anautogenous braconid Coeloides bostrichorum Giraud had a longer pre-oviposition period (5.1 vs. 3.3 days), a greater egg load (8.1 vs. 6.1 eggs), survived longer and emerged later than the pteromalid Rhopalicus tutela (Walker). In contrast, R. tutela was autogenous and tended to be more fecund under constrained conditions (9.7 vs. 5.1 total offspring per female). The longer pre-oviposition period of the specialist C. bostrichorum, coupled with its greater longevity, afforded the opportunity of better synchronization of ovipositing females with late instar larvae of I. typographus. By contrast, the polyphagous R. tutela matured rapidly, allowing parasitism of both younger and older larval instars of I. typographus in addition to other species. These small differences favoured the co-occurrence of the two parasitoid species on the same attacked trees.

  14. 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

  15. Isolation and extreme sex-specific expression of cytochrome P450 genes in the bark beetle, Ips paraconfusus, following feeding on the phloem of host ponderosa pine, Pinus ponderosa.

    PubMed

    Huber, D P W; Erickson, M L; Leutenegger, C M; Bohlmann, J; Seybold, S J

    2007-06-01

    We have identified cDNAs and characterized the expression of 13 novel cytochrome P450 genes of potential importance in host colonization and reproduction by the California fivespined ips, Ips paraconfusus. Twelve are of the Cyp4 family and one is of the Cyp9 family. Following feeding on host Pinus ponderosa phloem, bark beetle transcript levels of several of the Cyp4 genes increased or decreased in males only or in both sexes. In one instance (IparaCyp4A5) transcript accumulated significantly in females, but declined significantly in males. The Cyp9 gene (Cyp9T1) transcript levels in males were > 85 000 x higher at 8 h and > 25 000 x higher at 24 h after feeding compared with nonfed controls. Transcript levels in females were approximately 150 x higher at 24 h compared with nonfed controls. Cyp4G27 transcript was present constitutively regardless of sex or feeding and served as a better housekeeping gene than beta-actin or 18S rRNA for the real-time TaqMan polymerase chain reaction analysis. The expression patterns of Cyp4AY1, Cyp4BG1, and, especially, Cyp9T1 in males suggest roles for these genes in male-specific aggregation pheromone production. The differential transcript accumulation patterns of these bark beetle P450s provide insight into ecological interactions of I. paraconfusus with its host pines.

  16. 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.

  17. Induced Terpene Accumulation in Norway Spruce Inhibits Bark Beetle Colonization in a Dose-Dependent Manner

    PubMed Central

    Zhao, Tao; Krokene, Paal; Hu, Jiang; Christiansen, Erik; Björklund, Niklas; Långström, Bo; Solheim, Halvor; Borg-Karlson, Anna-Karin

    2011-01-01

    Background Tree-killing bark beetles (Coleoptera, Scolytinae) are among the most economically and ecologically important forest pests in the northern hemisphere. Induction of terpenoid-based oleoresin has long been considered important in conifer defense against bark beetles, but it has been difficult to demonstrate a direct correlation between terpene levels and resistance to bark beetle colonization. Methods To test for inhibitory effects of induced terpenes on colonization by the spruce bark beetle Ips typographus (L.) we inoculated 20 mature Norway spruce Picea abies (L.) Karsten trees with a virulent fungus associated with the beetle, Ceratocystis polonica (Siem.) C. Moreau, and investigated induced terpene levels and beetle colonization in the bark. Results Fungal inoculation induced very strong and highly variable terpene accumulation 35 days after inoculation. Trees with high induced terpene levels (n = 7) had only 4.9% as many beetle attacks (5.1 vs. 103.5 attacks m−2) and 2.6% as much gallery length (0.029 m m−2 vs. 1.11 m m−2) as trees with low terpene levels (n = 6). There was a highly significant rank correlation between terpene levels at day 35 and beetle colonization in individual trees. The relationship between induced terpene levels and beetle colonization was not linear but thresholded: above a low threshold concentration of ∼100 mg terpene g−1 dry phloem trees suffered only moderate beetle colonization, and above a high threshold of ∼200 mg terpene g−1 dry phloem trees were virtually unattacked. Conclusion/Significance This is the first study demonstrating a dose-dependent relationship between induced terpenes and tree resistance to bark beetle colonization under field conditions, indicating that terpene induction may be instrumental in tree resistance. This knowledge could be useful for developing management strategies that decrease the impact of tree-killing bark beetles. PMID:22028932

  18. Ophiostoma species (Ascomycetes: Ophiostomatales) associated with bark beetles (Coleoptera: Scolytinae) colonizing Pinus radiata in northern Spain.

    PubMed

    Romón, Pedro; Zhou, XuDong; Iturrondobeitia, Juan Carlos; Wingfield, Michael J; Goldarazena, Arturo

    2007-06-01

    Bark beetles (Coleoptera: Scolytinae) are known to be associated with fungi, especially species of Ophiostoma sensu lato and Ceratocystis. However, very little is known about these fungi in Spain. In this study, we examined the fungi associated with 13 bark beetle species and one weevil (Coleoptera: Entiminae) infesting Pinus radiata in the Basque Country of northern Spain. This study included an examination of 1323 bark beetles or their galleries in P. radiata. Isolations yielded a total of 920 cultures, which included 16 species of Ophiostoma sensu lato or their asexual states. These 16 species included 69 associations between fungi and bark beetles and weevils that have not previously been recorded. The most commonly encountered fungal associates of the bark beetles were Ophiostoma ips, Leptographium guttulatum, Ophiostoma stenoceras, and Ophiostoma piceae. In most cases, the niche of colonization had a significant effect on the abundance and composition of colonizing fungi. This confirms that resource overlap between species is reduced by partial spatial segregation. Interaction between niche and time seldom had a significant effect, which suggests that spatial colonization patterns are rarely flexible throughout timber degradation. The differences in common associates among the bark beetle species could be linked to the different niches that these beetles occupy.

  19. Impacts of silvicultural thinning treatments on beetle trap captures and tree attacks during low bark beetle populations in ponderosa pine forests of northern Arizona.

    PubMed

    Gaylord, M L; Hofstetter, R W; Wagner, M R

    2010-10-01

    Our research used a combination of passive traps, funnel traps with lures, baited trees, and surveys of long-term thinning plots to assess the impacts of different levels of stand basal area (BA) on bark beetle tree attack and on trap captures of Ips spp., Dendroctonus spp., and their predators. The study occurred at two sites in ponderosa pine, Pinus ponderosa Dougl. ex Laws., forests, from 2004 to 2007 during low bark beetle populations. Residual stand BA ranged from 9.0 to 37.0 m2/ha. More predators and bark beetles were collected in passive traps in stands of lower BA than in stands of higher BA; however, significance varied by species and site, and total number of beetles collected was low. Height of the clear panel passive traps affected trap catches for some species at some sites and years. When pheromone lures were used with funnel traps [Ips pini (Say) lure: lanierone, +03/-97 ipsdienol], we found no significant difference in trap catches among basal area treatments for bark beetles and their predators. Similarly, when trees were baited (Dendroctonus brevicomis LeConte lure: myrcene, exo-brevicomin and frontalin), we found no significant difference for days to first bark beetle attack. Surveys of long-term thinning treatments found evidence of bark beetle attacks only in unthinned plots (approximately 37 m2/ha basal area). We discuss our results in terms of management implications for bark beetle trapping and control.

  20. 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.

  1. Ecological interactions of bark beetles with host trees

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Certain species of bark beetles in the insect order Coleoptera, family Curculionidae (formerly Scolytidae) are keystone species in forest ecosystems. However, the tree-killing and woodboring bark and ambrosia beetles are also among the most damaging insects of forest products including lumber, paper...

  2. Bark beetle outbreaks in western North America: causes and consequences

    USGS Publications Warehouse

    Bentz, Barbara; Logan, Jesse; MacMahon, James A.; Allen, Craig D.; Ayres, Matt; Berg, Edward E; Carroll, Allan; Hansen, Matt; Hicke, Jeff H.; Joyce, Linda A.; Macfarlane, Wallace; Munson, Steve; Negron, Jose; Paine, Tim; Powell, Jim; Raffa, Kenneth; Regniere, Jacques; Reid, Mary; Romme, Bill; Seybold, Steven J.; Six, Diana; Vandygriff, Jim; Veblen, Tom; White, Mike; Witcosky, Jeff; Wood, David

    2005-01-01

    Since 1990, native bark beetles have killed billions of trees across millions of acres of forest from Alaska to northern Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, which are occurring simultaneously across western North America, are the largest and most severe in recorded history.

  3. Volatile Organic Compounds Emitted by Fungal Associates of Conifer Bark Beetles and their Potential in Bark Beetle Control.

    PubMed

    Kandasamy, Dineshkumar; Gershenzon, Jonathan; Hammerbacher, Almuth

    2016-09-01

    Conifer bark beetles attack and kill mature spruce and pine trees, especially during hot and dry conditions. These beetles are closely associated with ophiostomatoid fungi of the Ascomycetes, including the genera Ophiostoma, Grosmannia, and Endoconidiophora, which enhance beetle success by improving nutrition and modifying their substrate, but also have negative impacts on beetles by attracting predators and parasites. A survey of the literature and our own data revealed that ophiostomatoid fungi emit a variety of volatile organic compounds under laboratory conditions including fusel alcohols, terpenoids, aromatic compounds, and aliphatic alcohols. Many of these compounds already have been shown to elicit behavioral responses from bark beetles, functioning as attractants or repellents, often as synergists to compounds currently used in bark beetle control. Thus, these compounds could serve as valuable new agents for bark beetle management. However, bark beetle associations with fungi are very complex. Beetle behavior varies with the species of fungus, the stage of the beetle life cycle, the host tree quality, and probably with changes in the emission rate of fungal volatiles. Additional research on bark beetles and their symbiotic associates is necessary before the basic significance of ophiostomatoid fungal volatiles can be understood and their applied potential realized.

  4. 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...

  5. 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.

  6. Spatial and temporal dynamics of bark beetles in Chinese white pine in Qinling Mountains of Shaanxi Province, China.

    PubMed

    Chen, H; Tang, M

    2007-10-01

    Spatial and temporal dynamics of bark beetles in single tree trunks of Pinus armandi were studied in Qinling Mountains, Shaanxi Province, China. Ten species of engraver bark beetles attacked from healthy to withered Chinese white pines, but seven species were commonly detected every year in Qinling forest ecosystem. Dendroctonus armandi and Hylurgops longipilis were common species at the lower of trunks, and Ips acuminatus, Polygraphus sinensis, and Pityogenes japonicus primary distributed in the middle of trunks, whereas population densities of Cryphalus lipingensis and C. chinlingensis centralized at the upper trunks and branches of Chinese white pines. On the time series, D. armandi, as a dominant species in Chinese white pines of Qinling forest ecosystem, mainly attacked healthy and weakened trees and cooperated with blue stain fungus that resulted in the declining abruptly resistance and triggered the secondary bark beetles to attack the infected or withered host trees. Attacking and colonizing phenology of bark beetles in Qinling forest ecosystem are caused by complex interactions among spatial and trophic competition and cooperation and exhibit particular spatial and temporal patterns. Our results support the view that competition and cooperation within bark beetles are a critical factor to influence bark beetles spatial and temporal distribution, and stability of bark beetles' ecosystem, D. armandi, I. acuminatus, P. japonicus, P. sinensis, C. lipingensis, C. chinlingensis, and H. longipilis in Chinese white pine of Qinling forest ecosystem.

  7. Efficacy of two systemic insecticides injected into loblolly pine for protection against southern pine bark beetles (Coleoptera: Curculionidae).

    PubMed

    Grosman, Donald M; Clarke, Stephen R; Upton, William W

    2009-06-01

    We evaluated the efficacy of systemic insecticides emamectin benzoate and fipronil for preventing mortality of individual loblolly pines, Pinus taeda L., as a result of attacks by southern pine bark beetles (Coleoptera: Curculionidae, Scolytinae) for two consecutive years in Mississippi (2005-2006) and Alabama (2006-2007). Trees were injected once in the spring of 2005 (Mississippi) or 2006 (Alabama) and then were baited with species-specific bark beetle lures several weeks later. The southern pine beetle, Dendroctonus frontalis Zimmermann, was the target species but was changed to Ips spp. in Mississippi (but not Alabama) the second year because of few southern pine beetle attacks on baited trees. Single injections of emamectin benzoate were effective in reducing tree mortality caused by bark beetles compared with untreated checks. Although less effective overall, fipronil also significantly reduced tree mortality from southern pine beetle compared with the checks during the second year in Alabama. Tree mortality continued well after the lures had been removed. Evaluations of bolts taken from experimental trees killed in 2006 indicated that emamectin benzoate effectively prevented parent bark beetle gallery construction and that fipronil significantly reduced lengths of galleries constructed by adult beetles, brood development, and emergence, compared with checks. In contrast, neither insecticide treatment prevented the bark beetles from inoculating blue stain fungi, Ophiostoma spp., into treated trees.

  8. Counterturns initiated by decrease in rate of increase of concentration : Possible mechanism of chemotaxis by walking femaleIps paraconfusus bark beetles.

    PubMed

    Patrick Akers, R

    1989-01-01

    The position of beetles were marked at 1-sec intervals after they were released in still air 16-18 cm from point sources of pheromone. Characteristics of the tracks were quantified and compared to those that might be produced by counterturning schemakinesis, tropotaxis, klinotaxis, zigzagging, look-and-leap, or steepest-ascent schemakinesis mechanisms. The beetles' movements were highly irregular, but they turned almost continually and never fixed on a heading near 0° (=straight towards the source). Turn angle sizes increased slightly with absolute size of heading but had the opposite sign, thus compensating slightly for heading. Their distribution was centered about 0° and was unimodal. Heading decreased gradually as the source was neared, but the decrease became steeper within 1-5 cm of the source. Histograms showed that the maximum headings between occurrences when the beetle was headed directly towards the source (0°) were centered around 0° and most of them were less than 90°. However, maximum headings between 90° and 180° were not uncommon. Turn radius decreased as the source was neared. The counterturning mechanism was the most consistent with these observations. An analysis of rate of change of concentration with respect to heading and distance to the source further demonstrated that the counterturning mechanism could explain the form of the decrease in heading as the source was neared, if the major cue used to initiate counterturns was a decrease in the rate of increase of concentration. The tropotaxis could not recreate the form of the decrease, under any form of stimulus processing.

  9. 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)

  10. Inducibility of chemical defenses in Norway spruce bark is correlated with unsuccessful mass attacks by the spruce bark beetle.

    PubMed

    Schiebe, Christian; Hammerbacher, Almuth; Birgersson, Göran; Witzell, Johanna; Brodelius, Peter E; Gershenzon, Jonathan; Hansson, Bill S; Krokene, Paal; Schlyter, Fredrik

    2012-09-01

    Secondary attraction to aggregation pheromones plays a central role in the host colonization behavior of the European spruce bark beetle Ips typographus. However, it is largely unknown how the beetles pioneering an attack locate suitable host trees, and eventually accept or reject them. To find possible biomarkers for host choice by I. typographus, we analyzed the chemistry of 58 Norway spruce (Picea abies) trees that were subsequently either (1) successfully attacked and killed, (2) unsuccessfully attacked, or (3) left unattacked. The trees were sampled before the main beetle flight in a natural Norway spruce-dominated forest. No pheromones were used to attract beetles to the experimental trees. To test the trees' defense potential, each tree was treated in a local area with the defense hormone methyl jasmonate (MeJ), and treated and untreated bark were analyzed for 66 different compounds, including terpenes, phenolics and alkaloids. The chemistry of MeJ-treated bark correlated strongly with the success of I. typographus attack, revealing major chemical differences between killed trees and unsuccessfully attacked trees. Surviving trees produced significantly higher amounts of most of the 39 analyzed mono-, sesqui-, and diterpenes and of 4 of 20 phenolics. Alkaloids showed no clear pattern. Differences in untreated bark were less pronounced, where only 1,8-cineole and (-)-limonene were significantly higher in unsuccessfully attacked trees. Our results show that the potential of individual P. abies trees for inducing defense compounds upon I. typographus attack may partly determine tree resistance to this bark beetle by inhibiting its mass attack.

  11. Ethanol and (-)-alpha-Pinene: attractant kairomones for bark and ambrosia beetles in the southeastern US.

    PubMed

    Miller, Daniel R; Rabaglia, Robert J

    2009-04-01

    In 2002-2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (-)-alpha-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25-28 degrees C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (-)-alpha-pinene lures (release rate, 2-6 g/day at 25-28 degrees C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (-)-alpha-pinene in some locations. (-)-alpha-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70-97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (-)-alpha-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.

  12. Saproxylic community, guild and species responses to varying pheromone components of a pine bark beetle.

    PubMed

    Etxebeste, Iñaki; Lencina, José L; Pajares, Juan

    2013-10-01

    Some bark beetle species (Coleoptera: Scolytinae) produce aggregation pheromones that allow coordinated attack on their conifer hosts. As a new saproxylic habitat is founded, an assemblage of associated beetles kairomonally respond to bark beetle infochemicals. Ips sexdentatus is one of the major damaging insects of Pinus spp. in Southern Europe. Its response to varying ipsenol (Ie) percentages in relation to ipsdienol (Id) was studied in northwestern Spain, along with the entire saproxylic beetle assemblage captured at multiple-funnel traps. Response profile modeling was undertaken for I. sexdentatus sexes and sex-ratios, associated species and for selected trophic groups using a reference Gaussian model. In addition, the effects on the saproxylic assemblages were analyzed. I. sexdentatus response curve peaked at 22.7% Ie content, while remaining taxa that could be modeled, peaked above ca. 40% Ie. Predator guilds showed a linear relationship with Ie proportion, while competitors showed a delayed response peak. Consequently, species assemblages differed markedly between varying pheromone component mixtures. Given that the evaluated pheromonal proportions mimicked that of logs being colonized by I. sexdentatus, results suggested that the registered differential responses at different levels might provide I. sexdentatus with a temporal window that maximizes conspecific attraction while reducing interference with competitor and predatory guilds. Described responses might help improve the monitoring of the population status of target bark beetles and their associates, but also point toward the by-catch of many natural enemies, as well as rare saproxylic beetle species, interfering with the aims of sustainable forest management.

  13. Metabarcoding of fungal communities associated with bark beetles.

    PubMed

    Miller, Kirsten E; Hopkins, Kevin; Inward, Daegan J G; Vogler, Alfried P

    2016-03-01

    Many species of fungi are closely allied with bark beetles, including many tree pathogens, but their species richness and patterns of distribution remain largely unknown. We established a protocol for metabarcoding of fungal communities directly from total genomic DNA extracted from individual beetles, showing that the ITS3/4 primer pair selectively amplifies the fungal ITS. Using three specimens of bark beetle from different species, we assess the fungal diversity associated with these specimens and the repeatability of these estimates in PCRs conducted with different primer tags. The combined replicates produced 727 fungal Operational Taxonomic Units (OTUs) for the specimen of Hylastes ater, 435 OTUs for Tomicus piniperda, and 294 OTUs for Trypodendron lineatum, while individual PCR reactions produced on average only 229, 54, and 31 OTUs for the three specimens, respectively. Yet, communities from PCR replicates were very similar in pairwise comparisons, in particular when considering species abundance, but differed greatly among the three beetle specimens. Different primer tags or the inclusion of amplicons in separate libraries did not impact the species composition. The ITS2 sequences were identified with the Lowest Common Ancestor approach and correspond to diverse lineages of fungi, including Ophiostomaceae and Leotiomycetes widely found to be tree pathogens. We conclude that Illumina MiSeq metabarcoding reliably captures fungal diversity associated with bark beetles, although numerous PCR replicates are recommended for an exhaustive sample. Direct PCR from beetle DNA extractions provides a rapid method for future surveys of fungal species diversity and their associations with bark beetles and environmental variables.

  14. 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.

  15. Small beetle, large-scale drivers: how regional and landscape factors affect outbreaks of the European spruce bark beetle.

    PubMed

    Seidl, Rupert; Müller, Jörg; Hothorn, Torsten; Bässler, Claus; Heurich, Marco; Kautz, Markus

    2015-10-14

    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 10(3) to 10(10) m(2)) 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.

  16. 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

  17. Quantifying dispersal of a non-aggressive saprophytic bark beetle.

    PubMed

    Meurisse, Nicolas; Pawson, Stephen

    2017-01-01

    Long distance dispersal to locate suitable breeding sites is recognized as a key trait influencing the population dynamics and distribution of bark beetles and other saprophytic insects. While dispersal behavior has been studied for a range of aggressive 'tree killing' bark beetles, few have considered the dispersal behaviour of non-aggressive saprophytic bark beetles that utilize kairomones (host volatiles). We present the results of a mark-recapture experiment that examined adult dispersal patterns of the saprophytic bark beetle Hylurgus ligniperda. Releases took place in summer and autumn 2014, in a clearcut pine forest in the central North Island, New Zealand. Both flight-experienced and flight-naïve adults were marked and released in the center of a circular trap grid that extended to 960 m with 170 or 200 panel traps baited with a kairomone blend of alpha-pinene and ethanol. Of the 18,464 released H. ligniperda, 9,209 (49.9%) of the beetles flew, and 96 (1.04%) of the beetles that flew were recaptured. Individuals were recaptured at all distances. The recapture of flight-experienced beetles declined with dispersal distance, and a diffusion model showed heterogeneous dispersal tendencies within the population. Our best model estimated that 46% of flight-experienced beetles disperse > 1 km, and 1.6% > 5 km. Conversely, no declining pattern was shown in the recapture of flight-naïve beetles, suggesting that emerging H. ligniperda may require a period of flight to initiate chemotropic orientation behavior and subsequent attraction to traps. We discuss the implications of these findings for the management of phytosanitary risks. For instance, combining landscape knowledge of source populations with dispersal processes facilitates estimation of pest pressure at economically sensitive areas such as harvest and timber storage sites. Quantitative dispersal estimates also inform pest risk assessments by predicting spread rates for H. ligniperda that has proven

  18. 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.

  19. Disruption by conophthorin of the kairomonal response of sawyer beetles to bark beetle pheromones.

    PubMed

    Morewood, W D; Simmonds, K E; Gries, R; Allison, J D; Borden, J H

    2003-09-01

    Antennally active nonhost angiosperm bark volatiles were tested for their ability to reduce the response of three common species of coniferophagous wood-boring Cerambycidae to attractant-baited multiple funnel traps in the southern interior of British Columbia. Of the nonhost volatiles tested, only conophthorin was behaviorally active, disrupting the attraction of sawyer beetles, Monochamus spp., to traps baited with the host volatiles alpha-pinene and ethanol and the bark beetle pheromones ipsenol and ipsdienol. Conophthorin did not affect the attraction of sawyer beetles to the host kairomones alpha-pinene and ethanol in the absence of bark beetle pheromones, nor did it have any behavioral effect on adults of Xylotrechus longitarsis, which were not attracted to bark beetle pheromones. These results indicate that conophthorin does not act as a general repellent for coniferophagous Cerambycidae, as it seems to do for many species of Scolytidae, but has the specific activity of disrupting the kairomonal response of sawyer beetles to bark beetle pheromones.

  20. Response of native and exotic bark beetles to high-energy wind event in the Tian Shan Mountains, Kazakhstan

    NASA Astrophysics Data System (ADS)

    Mukhamadiev, N.; Lynch, A.; O'Connor, C.; Sagitov, A.; Panyushkina, I. P.

    2012-12-01

    On May 17, 2011, the spruce forest of Yile-Alatausky and Medeo National Parks in southeast Kazakhstan was surged by a high-energy cyclonic storm. Severe blowdown damaged several thousand hectare of Tian Shan spruce forest (Picea schrenkiana), with over 90% of trees killed in extensive areas. Bark beetle populations are increasing rapidly, particularly Ips hauseri, I. typographis, I. sexdentatus, and Pityogenes perfossus (all Coleoptera: Curculionidae). Little is known about the frequency or extent of either large storm events or bark beetle outbreaks in the Tian Shan Mountains, nor about associations between outbreaks of these species and temperature and precipitation regimes. Local managers are concerned that triggering bark beetle outbreaks during current unusually warm, dry conditions will have devastating consequences for the residual forest and forest outside of the blowdown. We characterize the bark beetle population response to the 2011 event to date, and reconstruct the temporal and spatial dynamics of historical disturbance events in the area using dendrochronology. Additionally temperature and precipitation-sensitive tree-ring width chronologies from the Tian Shan Mountains are analyzed to determine high- and low-frequency variability of climate for the past 200 years. Catastrophic windstorm disturbances may play a crucial role in determining forest structure across the mountains. We hypothesize that the Tian Shan spruce forest could be prone to severe storm winds and subsequent bark beetle outbreaks and never reach an old-growth phase between events.

  1. 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

  2. Novel forest decline triggered by multiple interactions among climate, an introduced pathogen and bark beetles.

    PubMed

    Wong, Carmen M; Daniels, Lori D

    2016-11-05

    Novel forest decline is increasing due to global environmental change, yet the causal factors and their interactions remain poorly understood. Using tree ring analyses, we show how climate and multiple biotic factors caused the decline of whitebark pine (Pinus albicaulis) in 16 stands in the southern Canadian Rockies. In our study area, 72% of whitebark pines were dead and 18% had partially dead crowns. Tree mortality peaked in the 1970s; however, the annual basal area increment of disturbed trees began to decline significantly in the late 1940s. Growth decline persisted up to 30 years before trees died from mountain pine beetle (Dendroctonus ponderosae), Ips spp. bark beetles or non-native blister rust pathogen (Cronartium ribicola). Climate-growth relations varied over time and differed among the healthy and disturbed subpopulations of whitebark pine. Prior to the 1940s, cool temperatures limited the growth of all subpopulations. Growth of live, healthy trees became limited by drought during the cool phase (1947 -1976) of the Pacific Decadal Oscillation (PDO) and then reverted to positive correlations with temperature during the subsequent warm PDO phase. In the 1940s, the climate-growth relations of the disturbed subpopulations diverged from the live, healthy trees with trees ultimately killed by mountain pine beetle diverging the most. We propose that multiple factors interacted over several decades to cause unprecedented rates of whitebark pine mortality. Climatic variation during the cool PDO phase caused drought stress that may have predisposed trees to blister rust. Subsequent decline in snowpack and warming temperatures likely incited further climatic stress and with blister rust reduced tree resistance to bark beetles. Ultimately, bark beetles and blister rust contributed to tree death. Our findings suggest the complexity of whitebark pine decline and the importance of considering multiway drought-disease-insect interactions over various timescales when

  3. Evaluation of funnel traps for characterizing the bark beetle (Coleoptera: Scolytidae) communities in ponderosa pine forests of north-central Arizona.

    PubMed

    Hayes, Christopher J; DeGomez, Tom E; Clancy, Karen M; Williams, Kelly K; McMillin, Joel D; Anhold, John A

    2008-08-01

    Lindgren funnel traps baited with aggregation pheromones are widely used to monitor and manage populations of economically important bark beetles (Coleoptera: Scolytidae). This study was designed to advance our understanding of how funnel trap catches assess bark beetle communities and relative abundance of individual species. In the second year (2005) of a 3-yr study of the bark beetle community structure in north-central Arizona pine (Pinus spp.) forests, we collected data on stand structure, site conditions, and local bark beetle-induced tree mortality at each trap site. We also collected samples of bark from infested (brood) trees near trap sites to identify and determine the population density of bark beetles that were attacking ponderosa pine, Pinus ponderosa Douglas ex Lawson, in the area surrounding the traps. Multiple regression models indicated that the number of Dendroctonus and Ips beetles captured in 2005 was inversely related to elevation of the trap site, and positively associated with the amount of ponderosa pine in the stand surrounding the site. Traps located closer to brood trees also captured more beetles. The relationship between trap catches and host tree mortality was weak and inconsistent in forest stands surrounding the funnel traps, suggesting that trap catches do not provide a good estimate of local beetle-induced tree mortality. However, pheromone-baited funnel trap data and data from gallery identification in bark samples produced statistically similar relative abundance profiles for the five species of bark beetles that we examined, indicating that funnel trap data provided a good assessment of species presence and relative abundance.

  4. Bark Beetle Outbreaks Increase Fire Probability in Western United States Forests

    NASA Astrophysics Data System (ADS)

    Bisrat, S. A.; White, M. A.

    2006-12-01

    Many of the direct influences of disturbances such as fire or insects on ecosystem function are well known. In contrast, the interactions among disturbances are less well understood. In the forests of the western United States, the interaction between bark beetle outbreaks and subsequent fires is a pressing management concern for a diverse political, economic, and ecological community but the disturbance interaction is generally unknown. For example, although conventional wisdom holds that bark beetle outbreaks will increase fire risk, limited field studies suggest the opposite may be true. To our knowledge, no study has attempted to study bark beetle - fire interactions over the entire western United States. Here, using five years (2000-2004) of manually collected aerial detection survey (ADS) polygons depicting the extent of bark beetle outbreaks and five years (2001-2005) of Moderate Resolution Imaging Spectroradiometer (MODIS) 1km fire images (MOD14), we calculated the influence of bark beetle outbreaks on one-year-lagged subsequent fire occurrence across the entire western United States. We converted the ADS polygons to raster format and co-registered all imagery to the Albers Equal Area projection. We then calculated the conditional probability of fire given bark beetle presence P(fire|bark beetles presence) and the conditional probability of fire given bark beetle absence P(fire|bark beetle absence). The presence of bark beetles increased the probability of one-year-lagged subsequent fire occurrence by 17% to 115% with an average value of 65%, strongly suggesting that bark beetle outbreaks in one year will increase the risk of fire in the next year. Key words: bark beetles, fire, disturbance interaction, conditional probability

  5. Coffee berry borer joins bark beetles in coffee klatch.

    PubMed

    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.

  6. 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.

  7. 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

  8. Climate change induced effects on the predisposition of forests of the water protection zone Wildalpen to disturbances by bark beetles

    NASA Astrophysics Data System (ADS)

    Baier, P.; Pennerstorfer, J.; Schopf, A.

    2012-04-01

    The provision of drinking water of high quality is a precious service of forests. Large-scale disturbances like forest fires, wind throws, pest outbreaks and subsequent clear cutting may lead to changes in hydrology (runoff as well as percolation). Furthermore, water quality can be negatively influenced by increased erosion, increased decomposition of litter and humus and leaching of nitrate. Large-scale epidemics of forest pests may induce forest decline at landscape scale with subsequent long-lasting negative effects on water quality. The European spruce bark beetle, Ips typographus (L.), is one of the most significant sources of mortality in mature spruce forest ecosystems in Eurasia. The objective of this study was to apply a complex predisposition assessment system for hazard rating and for the evaluation of climate change impacts for the water protection forests of the City of Vienna in Wildalpen. The following steps have been done to adapt/apply the bark beetle phenology model and the hazard rating system: -application, adaptation and validation of the bark beetle phenology model PHENIPS concerning start of dispersion, brood initiation, duration of development, beginning of sister broods, voltinism and hibernation - spatial/temporal modelling of the phenology and voltinism of I. typographus using past, present as well as projected climate data - application and validation of the stand- and site related long-term predisposition assessment system using forest stand/site data, annual damage reports and outputs of phenology modelling as data input - mapping of endangered areas and assessment of future susceptibility to infestations by I. typographus and other disturbing agents based on climate scenarios using GIS. The assessment of site- and stand-related predisposition revealed that the forest stands in Wildalpen are highly susceptible to bark beetle infestation. More than 65% of the stands were assigned to the predisposition classes high/very high. Only 10% of

  9. The role of phytopathogenicity in bark beetle-fungus symbioses: a challenge to the classic paradigm.

    PubMed

    Six, Diana L; Wingfield, Michael J

    2011-01-01

    The idea that phytopathogenic fungi associated with tree-killing bark beetles are critical for overwhelming tree defenses and incurring host tree mortality, herein called the classic paradigm (CP), has driven research on bark beetle-fungus symbiosis for decades. It has also strongly influenced our views of bark beetle ecology. We discuss fundamental flaws in the CP, including the lack of consistency of virulent fungal associates with tree-killing bark beetles, the lack of correspondence between fungal growth in the host tree and the development of symptoms associated with a successful attack, and the ubiquity of similar associations of fungi with bark beetles that do not kill trees. We suggest that, rather than playing a supporting role for the host beetle (tree killing), phytopathogenicity performs an important role for the fungi. In particular, phytopathogenicity may mediate competitive interactions among fungi and support survival and efficient resource capture in living, defensive trees.

  10. 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

  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. A common fungal associate of the spruce bark beetle metabolizes the stilbene defenses of Norway spruce.

    PubMed

    Hammerbacher, Almuth; Schmidt, Axel; Wadke, Namita; Wright, Louwrance P; Schneider, Bernd; Bohlmann, Joerg; Brand, Willi A; Fenning, Trevor M; Gershenzon, Jonathan; Paetz, Christian

    2013-07-01

    Norway spruce (Picea abies) forests suffer periodic fatal attacks by the bark beetle Ips typographus and its fungal associate, Ceratocystis polonica. Norway spruce protects itself against fungal and bark beetle invasion by the production of terpenoid resins, but it is unclear whether resins or other defenses are effective against the fungus. We investigated stilbenes, a group of phenolic compounds found in Norway spruce bark with a diaryl-ethene skeleton with known antifungal properties. During C. polonica infection, stilbene biosynthesis was up-regulated, as evidenced by elevated transcript levels of stilbene synthase genes. However, stilbene concentrations actually declined during infection, and this was due to fungal metabolism. C. polonica converted stilbenes to ring-opened, deglycosylated, and dimeric products. Chromatographic separation of C. polonica protein extracts confirmed that these metabolites arose from specific fungal enzyme activities. Comparison of C. polonica strains showed that rapid conversion of host phenolics is associated with higher virulence. C. polonica is so well adapted to its host's chemical defenses that it is even able to use host phenolic compounds as its sole carbon source.

  13. Co-occurence of Two Invasive Species: The Banded and European Elm Bark Beetles (Coleoptera: Scolytidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The invasive European elm bark beetle, Scolytus multistriatus (Marsham), was first detected a century ago and now occurs in most of the continental United States. The invasive banded elm bark beetle, Scolytus schevyrewi Semenov, native to Asia, was discovered in the United States in 2003 and is now...

  14. 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.

  15. Influence of elevation on bark beetle (Coleoptera: Curculionidae, Scolytinae) community structure and flight periodicity in ponderosa pine forests of Arizona.

    PubMed

    Williams, Kelly K; McMillin, Joel D; DeGomez, Tom E; Clancy, Karen M; Miller, Andy

    2008-02-01

    We examined abundance and flight periodicity of five Ips and six Dendroctonus species (Coleoptera: Curculionidae, Scolytinae) among three different elevation bands in ponderosa pine (Pinus ponderosa Douglas ex. Lawson) forests of northcentral Arizona. Bark beetle populations were monitored at 10 sites in each of three elevation bands (low: 1,600-1,736 m; middle: 2,058-2,230 m; high: 2,505-2,651 m) for 3 yr (2004-2006) using pheromone-baited Lindgren funnel traps. Trap contents were collected weekly from March to December. We also studied temperature differences among the elevation bands and what role this may play in beetle flight behavior. Bark beetles, regardless of species, showed no consistent elevational trend in abundance among the three bands. The higher abundances of Ips lecontei Swaine, I. calligraphus ponderosae Swaine, Dendroctonus frontalis Zimmerman, and D. brevicomis LeConte at low and middle elevations offset the greater abundance of I. knausi Swaine, D. adjunctus Blandford, D. approximatus Dietz, and D. valens LeConte at high elevations. I. pini (Say) and I. latidens LeConte were found in similar numbers across the three bands. Flight periodicity of several species varied among elevation bands. In general, the flight period shortened as elevation increased; flight initiated later and terminated earlier in the year. The timing, number, and magnitude of peaks in flight activity also varied among the elevation bands. These results suggest that abundance and flight seasonality of several bark beetles are related to elevation and the associated temperature differences. The implications of these results are discussed in relation to bark beetle management and population dynamics.

  16. Response of the engraver beetle, IPS perturbatus, to semiochemicals in white spruce stands of interior Alaska. Forest Service research paper

    SciTech Connect

    Werner, R.A.

    1993-05-01

    Field tests on the efficacy of various scolytid bark beetle pheromones to attract Ips perturbatus (Eichhoff) were conducted from 1977 through 1992 in stands of white spruce (Picea glauca (Moench) Voss) in interior Alaska. Several pheromones attracted high numbers of I. perturbatus and species of the predator Thanasimus to baited funnel traps. Test results also indicated that attacks by I. perturbatus may be deferred by certain semiochemicals.

  17. Bark beetle pheromones and pine volatiles: attractant kairomone lure blend for longhorn beetles (Cerambycidae) in pine stands of the southeastern United States.

    PubMed

    Miller, Daniel R; Asaro, Chris; Crowe, Christopher M; Duerr, Donald A

    2011-08-01

    In 2006, we examined the flight responses of 43 species of longhorn beetles (Coleoptera: Cerambycidae) to multiple-funnel traps baited with binary lure blends of (1) ipsenol + ipsdienol, (2) ethanol + alpha-pinene, and a quaternary lure blend of (3) ipsenol + ipsdienol + ethanol + alpha-pinene in the southeastern United States. In addition, we monitored responses of Buprestidae, Elateridae, and Curculionidae commonly associated with pine longhorn beetles. Field trials were conducted in mature pine (Pinus pp.) stands in Florida, Georgia, Louisiana, and Virginia. The following species preferred traps baited with the quaternary blend over those baited with ethanol + alpha-pinene: Acanthocinus nodosus (F.), Acanthocinus obsoletus (Olivier), Astylopsis arcuata (LeConte), Astylopsis sexguttata (Say), Monochamus scutellatus (Say), Monochamus titillator (F.) complex, Rhagium inquisitor (L.) (Cerambycidae), Buprestis consularis Gory, Buprestis lineata F. (Buprestidae), Ips avulsus (Eichhoff), Ips calligraphus (Germar), Ips grandicollis (Eichhoff), Orthotomicus caelatus (Eichhoff), and Gnathotrichus materiarus (Fitch) (Curculionidae). The addition ofipsenol and ipsdienol had no effect on catches of 17 other species of bark and wood boring beetles in traps baited with ethanol and a-pinene. Ethanol + alpha-pinene interrupted the attraction of Ips avulsus, I. grandicollis, and Pityophthorus Eichhoff spp. (but not I. calligraphus) (Curculionidae) to traps baited with ipsenol + ipsdienol. Our results support the use of traps baited with a quaternary blend of ipsenol + ipsdienol + ethanol + alpha-pinene for common saproxylic beetles in pine forests of the southeastern United States.

  18. Bark beetles and pinhole borers (Curculionidae, Scolytinae, Platypodinae) alien to Europe.

    PubMed

    R Kirkendall, Lawrence; Faccoli, Massimo

    2010-09-17

    Invasive bark beetles are posing a major threat to forest resources around the world. DAISIE's web-based and printed databases of invasive species in Europe provide an incomplete and misleading picture of the alien scolytines and platypodines. We present a review of the alien bark beetle fauna of Europe based on primary literature through 2009. We find that there are 18 Scolytinae and one Platypodinae species apparently established in Europe, from 14 different genera. Seventeen species are naturalized. We argue that Trypodendron laeve, commonly considered alien in Europe, is a native species; conversely, we hypothesize that Xyleborus pfeilii, which has always been treated as indigenous, is an alien species from Asia. We also point out the possibility that the Asian larch bark beetle Ips subelongatus is established in European Russia. We show that there has been a marked acceleration in the rate of new introductions to Europe, as is also happening in North America: seven alien species were first recorded in the last decade.We present information on the biology, origins, and distributions of the alien species. All but four are polyphagous, and 11 are inbreeders: two traits which increase invasiveness. Eleven species are native to Asia, six to the Americas, and one is from the Canary Islands. The Mediterranean is especially favorable for invasives, hosting a large proportion of the aliens (9/19). Italy, France and Spain have the largest numbers of alien species (14, 10 and 7, respectively). We point out that the low numbers for at least some countries is likely due to under-reporting.Finally, we discuss the difficulties associated with identifying newly invasive species. Lack of good illustrations and keys hinder identification, particularly for species coming from Asia and Oceania.

  19. Bark beetles and pinhole borers (Curculionidae, Scolytinae, Platypodinae) alien to Europe

    PubMed Central

    R. Kirkendall, Lawrence; Faccoli, Massimo

    2010-01-01

    Abstract Invasive bark beetles are posing a major threat to forest resources around the world. DAISIE’s web-based and printed databases of invasive species in Europe provide an incomplete and misleading picture of the alien scolytines and platypodines. We present a review of the alien bark beetle fauna of Europe based on primary literature through 2009. We find that there are 18 Scolytinae and one Platypodinae species apparently established in Europe, from 14 different genera. Seventeen species are naturalized. We argue that Trypodendron laeve, commonly considered alien in Europe, is a native species; conversely, we hypothesize that Xyleborus pfeilii, which has always been treated as indigenous, is an alien species from Asia. We also point out the possibility that the Asian larch bark beetle Ips subelongatus is established in European Russia. We show that there has been a marked acceleration in the rate of new introductions to Europe, as is also happening in North America: seven alien species were first recorded in the last decade. We present information on the biology, origins, and distributions of the alien species. All but four are polyphagous, and 11 are inbreeders: two traits which increase invasiveness. Eleven species are native to Asia, six to the Americas, and one is from the Canary Islands. The Mediterranean is especially favorable for invasives, hosting a large proportion of the aliens (9/19). Italy, France and Spain have the largest numbers of alien species (14, 10 and 7, respectively). We point out that the low numbers for at least some countries is likely due to under-reporting. Finally, we discuss the difficulties associated with identifying newly invasive species. Lack of good illustrations and keys hinder identification, particularly for species coming from Asia and Oceania. PMID:21594183

  20. Olfactory experience modifies semiochemical responses in a bark beetle predator.

    PubMed

    Costa, Arnaud; Reeve, John D

    2011-11-01

    A typical feature of forest insect pests is their tendency to undergo large fluctuations in abundance, which can jeopardize the persistence of their predaceous natural enemies. One strategy that these predators may adopt to cope with these fluctuations would be to respond to sensory cues for multiple prey species. Another possible adaptation to temporal variation in the prey community could involve the learning of prey cues and switching behavior. We conducted three experiments to investigate the ability of the generalist bark beetle predator Thanasimus dubius (F.) (Coleoptera: Cleridae) to respond to different prey signals and to investigate the effect of olfactory experience. We first conducted a field choice test and a wind tunnel experiment to examine the kairomonal response of individual predators toward prey pheromone components (frontalin, ipsenol, ipsdienol, sulcatol) along with the pine monoterpene α-pinene, which is a volatile compound from the host of the prey. We also presented semiochemically naive predators with two prey pheromone components, frontalin and ipsenol, alone or associated with a reward. Our results showed that T. dubius populations are composed of generalists that can respond to a broad range of kairomonal signals. Naive T. dubius also were more attracted to ipsenol following its association with a reward. This work constitutes the first evidence that the behavior of a predatory insect involved in bark beetle population dynamics is influenced by previous olfactory experience, and provides a potential explanation for the pattern of prey switching observed in field studies.

  1. Biological factors contributing to bark and ambrosia beetle species diversification.

    PubMed

    Gohli, Jostein; Kirkendall, Lawrence R; Smith, Sarah M; Cognato, Anthony I; Hulcr, Jiri; Jordal, Bjarte H

    2017-03-03

    The study of species diversification can identify the processes that shape patterns of species richness across the tree of life. Here we perform comparative analyses of species diversification using a large dataset of bark beetles. Three examined covariates - permanent inbreeding (sibling mating), fungus farming, and major host type - represent a range of factors that may be important for speciation. We studied the association of these covariates with species diversification while controlling for evolutionary lag on adaptation. All three covariates were significantly associated with diversification, but fungus farming showed conflicting patterns between different analyses. Genera that exhibited interspecific variation in host type had higher rates of species diversification, which may suggest that host switching is a driver of species diversification or that certain host types or forest compositions facilitate colonization and thus allopatric speciation. Because permanent inbreeding is thought to facilitate dispersal, the positive association of permanent inbreeding on diversification rates suggests that dispersal ability may contribute to species richness. Bark beetles are ecologically unique; however, our results indicate that their impressive species diversity is largely driven by mechanisms shown to be important for many organism groups. This article is protected by copyright. All rights reserved.

  2. Influence of bark beetles outbreaks on the carbon balance of western United States forests

    NASA Astrophysics Data System (ADS)

    Ghimire, B.; Williams, C. A.; Collatz, G. J.; Masek, J. G.

    2011-12-01

    Recently bark beetle outbreaks have been increasing in western United States forests due to increases in temperatures and prolonged occurrence of droughts. Bark beetle outbreaks transfer carbon from the live photosynthesizing pools to the dead respiring pool where carbon slowly decomposes into the atmosphere causing landscapes to change from a net sink to source of carbon. Previous studies have usually been conducted at small localized areas, focused only on one or two bark beetle types or encompass a single outbreak event. The literature largely ignores the influence of bark beetle mortality on carbon balance at both local and regional scales by focusing on multiple bark beetles types and events. This study uses a combination of the Carnegie Ames Stanford Approach (CASA) carbon cycle model driven by remotely sensed biophysical observations, Forest Inventory and Analysis (FIA) derived post-disturbance biomass regeneration trajectories, and mortality rates obtained from Aerial Detection Survey (ADS) insect outbreak polygons. The synthesis of the carbon cycle based modeling approach and different data products results in characteristic carbon trajectories for Net Ecosystem Productivity (NEP), Net Primary Productivity (NPP) and heterotrophic respiration associated with insect outbreaks. This study demonstrates that bark beetle events change landscapes from a sink to source of carbon at a local scale but at a larger regional level the influence of bark beetle outbreaks are not prominent compared to other disturbance agents.

  3. Do water-limiting conditions predispose Norway spruce to bark beetle attack?

    PubMed Central

    Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel

    2015-01-01

    Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel ‘attack box’ method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance byI. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials. PMID:25417785

  4. Do water-limiting conditions predispose Norway spruce to bark beetle attack?

    PubMed

    Netherer, Sigrid; Matthews, Bradley; Katzensteiner, Klaus; Blackwell, Emma; Henschke, Patrick; Hietz, Peter; Pennerstorfer, Josef; Rosner, Sabine; Kikuta, Silvia; Schume, Helmut; Schopf, Axel

    2015-02-01

    Drought is considered to enhance susceptibility of Norway spruce (Picea abies) to infestations by the Eurasian spruce bark beetle (Ips typographus, Coleoptera: Curculionidae), although empirical evidence is scarce. We studied the impact of experimentally induced drought on tree water status and constitutive resin flow, and how physiological stress affects host acceptance and resistance. We established rain-out shelters to induce both severe (two full-cover plots) and moderate (two semi-cover plots) drought stress. In total, 18 sample trees, which were divided equally between the above treatment plots and two control plots, were investigated. Infestation was controlled experimentally using a novel 'attack box' method. Treatments influenced the ratios of successful and defended attacks, but predisposition of trees to infestation appeared to be mainly driven by variations in stress status of the individual trees over time. With increasingly negative twig water potentials and decreasing resin exudation, the defence capability of the spruce trees decreased. We provide empirical evidence that water-limiting conditions impair Norway spruce resistance to bark beetle attack. Yet, at the same time our data point to reduced host acceptance by I. typographus with more extreme drought stress, indicated by strongly negative pre-dawn twig water potentials.

  5. 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.

  6. Effects of bark beetle-caused tree mortality on biogeochemical and biogeophysical MODIS products

    NASA Astrophysics Data System (ADS)

    Bright, Benjamin C.; Hicke, Jeffrey A.; Meddens, Arjan J. H.

    2013-07-01

    affect forest-atmosphere exchanges of carbon, water, and energy, thereby influencing weather and climate. Bark beetle outbreaks are one such disturbance type that alters biogeochemical and biogeophysical processes in forests. Few studies have documented bark beetle impacts to leaf area index (LAI), gross primary productivity (GPP), evapotranspiration (ET), land surface temperature (LST), and surface albedo with satellite observations. Our objective was to use Landsat-derived estimates of bark beetle-caused tree mortality and Moderate Resolution Imaging Spectroradiometer (MODIS) land surface products to estimate beetle-caused changes in LAI, GPP, ET, LST, and surface albedo in northern Colorado. Following bark beetle-caused tree mortality, decreases occurred in LAI (0.02-0.80 m2m-2, 1-40%), annual GPP (50-248 gC m-2 yr-1, (5-26%), and daily summer ET (0.20-0.70 mm day-1, 13-44%), whereas increases occurred in August LST (1-3.9 K) and February albedo (0.03-0.09, 19-52%). We found greater responses of these variables in areas of greater mortality severity. The extent and severity of tree mortality in northern Colorado caused substantial changes in land surface variables (9-23%) when averaged across all forested areas of our study area. Our results demonstrate that land surface variables are sensitive to bark beetle-caused tree mortality and that bark beetle outbreaks can significantly impact biogeochemical and biogeophysical processes.

  7. On the track of the Red Queen: bark beetles, their nematodes, local climate and geographic parthenogenesis.

    PubMed

    Meirmans, S; Skorping, A; Løyning, M K; Kirkendall, L R

    2006-11-01

    Geographic parthenogenesis has been explained as resulting from parasite pressure (Red Queen hypothesis): several studies have found high degrees of sexuals where the prevalence of parasites is high. However, it is important to address whether prevalence of parasites mirrors risk of infection. We explored geographic parthenogenesis of Ips acuminatus bark beetles and their nematodes. Local climate is crucial for nematode stages outside the host, in spring and summer, and prevalence should thus be associated with those temperatures if prevalence reliably reflects exposure risk across populations. This was the case; however, high prevalence of a virulent nematode species was not associated with many sexuals, whereas highly sexual populations were characterized by high infection risk of benign nematodes. Low virulence of the latter makes Red Queen dynamics unlikely. Geographical patterns of parthenogenesis were instead associated with winter temperature and variance in temperature.

  8. The Bark-Beetle-Associated Fungus, Endoconidiophora polonica, Utilizes the Phenolic Defense Compounds of Its Host as a Carbon Source.

    PubMed

    Wadke, Namita; Kandasamy, Dineshkumar; Vogel, Heiko; Lah, Ljerka; Wingfield, Brenda D; Paetz, Christian; Wright, Louwrance P; Gershenzon, Jonathan; Hammerbacher, Almuth

    2016-06-01

    Norway spruce (Picea abies) is periodically attacked by the bark beetle Ips typographus and its fungal associate, Endoconidiophora polonica, whose infection is thought to be required for successful beetle attack. Norway spruce produces terpenoid resins and phenolics in response to fungal and bark beetle invasion. However, how the fungal associate copes with these chemical defenses is still unclear. In this study, we investigated changes in the phenolic content of Norway spruce bark upon E. polonica infection and the biochemical factors mediating these changes. Although genes encoding the rate-limiting enzymes in Norway spruce stilbene and flavonoid biosynthesis were actively transcribed during fungal infection, there was a significant time-dependent decline of the corresponding metabolites in fungal lesions. In vitro feeding experiments with pure phenolics revealed that E. polonica transforms both stilbenes and flavonoids to muconoid-type ring-cleavage products, which are likely the first steps in the degradation of spruce defenses to substrates that can enter the tricarboxylic acid cycle. Four genes were identified in E. polonica that encode catechol dioxygenases carrying out these reactions. These enzymes catalyze the cleavage of phenolic rings with a vicinal dihydroxyl group to muconoid products accepting a wide range of Norway spruce-produced phenolics as substrates. The expression of these genes and E. polonica utilization of the most abundant spruce phenolics as carbon sources both correlated positively with fungal virulence in several strains. Thus, the pathways for the degradation of phenolic compounds in E. polonica, initiated by catechol dioxygenase action, are important to the infection, growth, and survival of this bark beetle-vectored fungus and may play a major role in the ability of I. typographus to colonize spruce trees.

  9. Utilizing NASA Satellite Missions to Identify Bark Beetle Infestation in Sequoia National Park

    NASA Astrophysics Data System (ADS)

    Newcomer, M. E.; Bird, J. E.; Sabatine, S. M.; Sady, G. C.; Stalzer, A. M.; Wheeler, T. A.; Skiles, J. W.; Schmidt, C.

    2009-12-01

    Bark beetle-induced tree mortality has increased over the last few decades, exacerbated by below-average precipitation and a loss of soil nutrients, forcing park managers to improve bark beetle monitoring techniques. Bark beetle dynamics were investigated during summer 2009 at 32 sites within Sequoia National Park, California with the aim of correlating field data with satellite imagery to provide forest managers with a more efficient methodology for tracking, monitoring, and forecasting bark beetle outbreaks. Field parameters included visual assessments of the presence and degree of bark beetle-induced mortality and percent canopy cover. Ancillary data such as relative leaf chlorophyll concentration and soil nutrients including sodium [Na+], nitrate [NO3-], and potassium [K+] were collected for each 15 × 15 meter plot. The relationship between bark beetle attacks and potassium [K+] shows higher concentrations in healthy areas. Additionally, algorithms from three satellites were used to identify areas of moisture and vegetation stress; including the Ratio Vegetation Index (RVI) from ASTER, Enhanced Wetness Difference Index (EWDI) from Landsat Thematic Mapper (TM5), Disturbance Index (DI) from MODIS, and four other vegetation indices from Landsat TM5. Vegetation indices show uniform stress across various years.

  10. 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.

  11. Cross-Attraction between an Exotic and a Native Pine Bark Beetle: A Novel Invasion Mechanism?

    PubMed Central

    Lu, Min; Miller, Daniel R.; Sun, Jiang-Hua

    2007-01-01

    Background Aside from the ecological impacts, invasive species fascinate ecologists because of the unique opportunities that invasives offer in the study of community ecology. Some hypotheses have been proposed to illustrate the mechanisms that allow exotics to become invasive. However, positive interactions between exotic and native insects are rarely utilized to explain invasiveness of pests. Methodology/Principal Findings Here, we present information on a recently formed association between a native and an exotic bark beetle on their shared host, Pinus tabuliformis, in China. In field examinations, we found that 35–40% of P. tabuliformis attacked by an exotic bark beetle, Dendroctonus valens, were also attacked by a native pine bark beetle, Hylastes parallelus. In the laboratory, we found that the antennal and walking responses of H. parallelus to host- and beetle-produced compounds were similar to those of the exotic D. valens in China. In addition, D. valens was attracted to volatiles produced by the native H. parallelus. Conclusions/Significance We report, for the first time, facilitation between an exotic and a native bark beetle seems to involve overlap in the use of host attractants and pheromones, which is cross-attraction. The concept of this interspecific facilitation could be explored as a novel invasive mechanism which helps explain invasiveness of not only exotic bark beetles but also other introduced pests in principle. The results reported here also have particularly important implications for risk assessments and management strategies for invasive species. PMID:18074026

  12. Effect of bark beetle infestation on secondary organic aerosol precursor emissions.

    PubMed

    Amin, Hardik; Atkins, P Tyson; Russo, Rachel S; Brown, Aaron W; Sive, Barkley; Hallar, A Gannet; Huff Hartz, Kara E

    2012-06-05

    Bark beetles are a potentially destructive force in forest ecosystems; however, it is not known how insect attacks affect the atmosphere. The emissions of volatile organic compounds (VOCs) were sampled i.) from bark beetle infested and healthy lodgepole pine (Pinus contorta var. latifolia) trees and ii.) from sites with and without active mountain pine beetle infestation. The emissions from the trunk and the canopy were collected via sorbent traps. After collection, the sorbent traps were extracted with hexane, and the extracts were separated and detected using gas chromatography/mass spectroscopy. Canister samples were also collected and analyzed by a multicolumn gas chromatographic system. The samples from bark beetle infested lodgepole pine trees suggest a 5- to 20-fold enhancement in total VOCs emissions. Furthermore, increases in the β-phellandrene emissions correlated with bark beetle infestation. A shift in the type and the quantity of VOC emissions can be used to identify bark beetle infestation but, more importantly, can lead to increases in secondary organic aerosol from these forests as potent SOA precursors are produced.

  13. Temporal clumping of bark beetle arrival at pheromone traps: Modeling anemotaxis in chaotic plumes.

    PubMed

    Byers, J A

    1996-11-01

    The sequence of arrival of the bark beetlesIps typographus andPityogenes chalcographus (Coleoptera: Scolytidae) at traps baited with their synthetic pheromones was monitored with a portable fraction collector. Histograms of the natural arrival patterns of both species were nonrandom and clumped at shorter time scales (1-, 2-, 4-, 5-, or 6-min cells) but appeared random at larger time scales (10, 20 or 30 min). Monte Carlo generation of similar histograms showed them to be random at all of these time scales. A stochastic computer model could graphically simulate insect orientation to odor sources based on present theories of odor-modulated anemotaxis and casting. Although this model was used throughout, since it assumes only that insects cast perpendicular to the current wind direction, a second model could slightly improve orientation success. However, the second model requires that the insect remember its ground path (upwind) prior to losing the plume (after an abrupt wind direction change). The effects of casting and flight parameters on orientation success and randomness of arrival sequence within various plumes were determined by simulation. Similarly, the effects of random walks in plume direction, plume width, and wind speed were explored. The results showed that dynamic random variations in plume direction and especially wind speed could cause an otherwise random arrival sequence (e.g., under constant wind) to become clumped and nonrandom. Therefore, the clumped arrival patterns of bark beetles and other insects, includingSpodoptera litura, at pheromone sources could result from random-walk fluctuations in wind speed and wind direction.

  14. Spatial characterization of bark beetle infestations by a multidate synergy of SPOT and Landsat imagery.

    PubMed

    Latifi, Hooman; Schumann, Bastian; Kautz, Markus; Dech, Stefan

    2014-01-01

    Biological infestations in forests, e.g. the insect outbreaks, have been shown as favoured by future climate change trends. In Europe, the European spruce bark beetle (Ips typographus L.) is one of the main agents causing substantial economic disturbances in forests. Therefore, studies on spatio-temporal characterization of the area affected by bark beetle are of major importance for rapid post-attack management. We aimed at spatially detecting damage classes by combining multidate remote sensing data and a non-parametric classification. As study site served a part of the Bavarian Forest National Park (Germany). For the analysis, we used 10 geometrically rectified scenes of Landsat and SPOT sensors in the period between 2001 and 2011. The main objective was to explore the potential of medium-resolution data for classifying the attacked areas. A further aim was to explore if the temporally adjacent infested areas are able to be separated. The random forest (RF) model was applied using the reference data drawn from high-resolution aerial imagery. The results indicate that the sufficiently large patches of visually identifiable damage classes can be accurately separated from non-attacked areas. In contrast to those, the other mortality classes (current year, current year 1 and current year 2 infested classes) were mostly classified with higher commission or omission errors as well as higher classification biases. The available medium-resolution satellite images, combined with properly acquired reference data, are concluded to be adequate tools to map area-based infestations at advanced stages. However, the quality of reference data, the size of infested patches and the spectral resolution of remotely sensed data are the decisive factors in case of smaller areas. Further attempts using auxiliary height information and spatially enhanced data may refine such an approach.

  15. Leptographium tereforme sp. nov. and other Ophiostomatales isolated from the root-feeding bark beetle Hylurgus ligniperda in California.

    PubMed

    Kim, Sujin; Harrington, Thomas C; Lee, Jana C; Seybold, Steven J

    2011-01-01

    The redhaired pine bark beetle Hylurgus ligniperda (F.) is native to Europe but was discovered in Los Angeles, California, in 2003. This root-and stump-feeding beetle is a common vector of Ophiostomatales, which are potential tree pathogens or causes of blue stain of conifer sapwood. In this study Ophiostomatales were isolated on a cycloheximide-amended medium from 118 adult H. ligniperda collected from infested logs of Pinus halepensis and P. pinea at two sites in California. In total eight species of Ophiostomatales were identified and seven species that occasionally were isolated were unidentified. The most frequently isolated species were Ophiostoma ips and Grosmannia galeiforme, which were isolated respectively from 31% and 23% of the 118 beetles. The other species isolated included O. piceae (isolated from 9% of the beetles), O. querci (8%) and Leptographium tereforme sp. nov. (6%). Grosmannia huntii, L. serpens, three Sporothrix species, O. floccosum, O. stenoceras, two unidentified Hyalorhinocladiella sp. and a sterile fungus each were isolated from fewer then 5% of beetles. Most of the identified species already were known in USA and have been found in association with H. ligniperda in other countries. However the new species, L. tereforme, and G. galeiforme were recorded from USA for the first time, and this is the first report of L. serpens from western North America.

  16. Bark and Ambrosia Beetles Show Different Invasion Patterns in the USA

    PubMed Central

    Rassati, Davide; Faccoli, Massimo; Haack, Robert A.; Rabaglia, Robert J.; Petrucco Toffolo, Edoardo; Battisti, Andrea; Marini, Lorenzo

    2016-01-01

    Non-native bark and ambrosia beetles represent a threat to forests worldwide. Their invasion patterns are, however, still unclear. Here we investigated first, if the spread of non-native bark and ambrosia beetles is a gradual or a discontinuous process; second, which are the main correlates of their community structure; third, whether those correlates correspond to those of native species. We used data on species distribution of non-native and native scolytines in the continental 48 USA states. These data were analyzed through a beta-diversity index, partitioned into species richness differences and species replacement, using Mantel correlograms and non-metric multidimensional scaling (NMDS) ordination for identifying spatial patterns, and regression on distance matrices to test the association of climate (temperature, rainfall), forest (cover area, composition), geographical (distance), and human-related (import) variables with β-diversity components. For both non-native bark and ambrosia beetles, β-diversity was mainly composed of species richness difference than species replacement. For non-native bark beetles, a discontinuous invasion process composed of long distance jumps or multiple introduction events was apparent. Species richness differences were primarily correlated with differences in import values while temperature was the main correlate of species replacement. For non-native ambrosia beetles, a more continuous invasion process was apparent, with the pool of non-native species arriving in the coastal areas that tended to be filtered as they spread to interior portions of the continental USA. Species richness differences were mainly correlated with differences in rainfall among states, while rainfall and temperature were the main correlates of species replacement. Our study suggests that the different ecology of bark and ambrosia beetles influences their invasion process in new environments. The lower dependency that bark beetles have on climate

  17. Bark and Ambrosia Beetles Show Different Invasion Patterns in the USA.

    PubMed

    Rassati, Davide; Faccoli, Massimo; Haack, Robert A; Rabaglia, Robert J; Petrucco Toffolo, Edoardo; Battisti, Andrea; Marini, Lorenzo

    2016-01-01

    Non-native bark and ambrosia beetles represent a threat to forests worldwide. Their invasion patterns are, however, still unclear. Here we investigated first, if the spread of non-native bark and ambrosia beetles is a gradual or a discontinuous process; second, which are the main correlates of their community structure; third, whether those correlates correspond to those of native species. We used data on species distribution of non-native and native scolytines in the continental 48 USA states. These data were analyzed through a beta-diversity index, partitioned into species richness differences and species replacement, using Mantel correlograms and non-metric multidimensional scaling (NMDS) ordination for identifying spatial patterns, and regression on distance matrices to test the association of climate (temperature, rainfall), forest (cover area, composition), geographical (distance), and human-related (import) variables with β-diversity components. For both non-native bark and ambrosia beetles, β-diversity was mainly composed of species richness difference than species replacement. For non-native bark beetles, a discontinuous invasion process composed of long distance jumps or multiple introduction events was apparent. Species richness differences were primarily correlated with differences in import values while temperature was the main correlate of species replacement. For non-native ambrosia beetles, a more continuous invasion process was apparent, with the pool of non-native species arriving in the coastal areas that tended to be filtered as they spread to interior portions of the continental USA. Species richness differences were mainly correlated with differences in rainfall among states, while rainfall and temperature were the main correlates of species replacement. Our study suggests that the different ecology of bark and ambrosia beetles influences their invasion process in new environments. The lower dependency that bark beetles have on climate

  18. Frequent, Low-Intensity Fire Increases Tree Defense To Bark Beetles

    NASA Astrophysics Data System (ADS)

    Hood, S.; Sala, A.

    2013-12-01

    Wildfire and bark beetles are the two largest disturbance agents in North American conifer forests and have interacted for millennia to drive forest composition, structure, and ecological processes. Recent widespread mortality in western coniferous forests due to bark beetle outbreaks have been attributed in part to increasing temperatures and drought associated with global climate change. In fire-dependent forests, fire exclusion has also led to uncharacteristically dense forests which are also thought to be more susceptible to bark beetle outbreaks due to increased drought stress in individual trees. These mortality events have spurred strong interest in the interaction of fire and bark beetles in driving forest dynamics under a changing climate. However, a fact that has not received adequate attention is whether fire exclusion in fire-dependent forests decreases allocation to tree defense, thereby making contemporary forests more prone to bark beetle outbreaks, regardless of climate and stand structure. Fire is known to increase constitutive resin production in many tree species, yet the impact of frequent fire on expression of better defended tree phenotypes has never been examined. We hypothesized that frequent, low-intensity fire increases tree resistance to bark beetle attack through systemic induced resistance. Using a combination of sampling in natural stands for which we had long-term fire history data and an experimental block design of four thinning and burning treatments, we examined the influence of fire and water stress on tree defense to determine if frequent fire increases tree defense and the degree to which water stress modulates this response. We used axial resin ducts as the measure of defense, as this is where resin is both stored and manufactured in Pinaceae. Resin duct production and density has also been shown to be a better indicator of mortality from bark beetle attacks than tree growth. Resin duct density increased after fire at all

  19. Associations of Conifer-Infesting Bark Beetles and Fungi in Fennoscandia

    PubMed Central

    Linnakoski, Riikka; de Beer, Z. Wilhelm; Niemelä, Pekka; Wingfield, Michael J.

    2012-01-01

    Bark beetles (Coleoptera, Scolytinae) have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota) that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them. PMID:26467956

  20. Associations of Conifer-Infesting Bark Beetles and Fungi in Fennoscandia.

    PubMed

    Linnakoski, Riikka; de Beer, Z Wilhelm; Niemelä, Pekka; Wingfield, Michael J

    2012-02-15

    Bark beetles (Coleoptera, Scolytinae) have a widespread association with fungi, especially with ophiostomatoid fungi (Ascomycota) that cause blue staining of wood, and in some cases, serious tree diseases. In Fennoscandia, most studies of these fungi have focused on economically important bark beetle species and this is likely to have led to a biased view of the fungal biodiversity in the region. Recently, the associations between fungi and bark beetles in Fennoscandia have been shown to be more diverse than previously thought. Furthermore, they form complex and dynamic associations that are only now beginning to emerge. This review examines the current knowledge of the rather poorly known interactions between bark beetles, fungi and their conifer host trees in Fennoscandia. The diversity of ophiostomatoid species is discussed and the possible factors that influence the assemblages of fungal associates are considered for all species that are known to occur in the region. For many ophiostomatoid species found in Fennoscandia, little or nothing is known regarding their pathogenicity, particularly if they were to be transferred to new environments. We, therefore, draw attention to the possible threats of timber trade and climate change-induced invasions of new habitats by bark beetles and the fungi that can be moved along with them.

  1. Trap trees for elm bark beetles : Augmentation with pheromone baits and chlorpyrifos.

    PubMed

    Lanier, G N; Jones, A H

    1985-01-01

    European elm bark beetles,Scolytus multistriatus (Marsh.), were strongly attracted to American elms,Ulmus americana L., baited with theS. multistriatus attractant, multilure, or killed by injection of the arboricide, cacodylic acid; a combination of the two treatments was most attractive. Comparisons of beetle catches on sticky bands affixed to the trees with samples of bark from the same trees showed that the number of beetles landing on cacodylic acid-treated trees was approximately 40 times greater than the number boring into them. Spraying the bark with the insecticide chlorpyrifos had no direct effect on attraction. No live bark beetle brood was found in trees that had been treated with cacodylic acid or chlorpyrifos, but trees that were only baited or left untreated (check) were attacked, killed, and colonized. We suggest that the contribution of the cacodylic acid trap tree technique to Dutch elm disease control will be enhanced by baiting treated trees with multilure and spraying their lower boles with 0.5% chlorpyrifos. This treatment will eliminate diseased and unwanted elms as potential breeding material and kill large numbers of elm bark beetles that might otherwise innoculate healthy elms with the Dutch elm disease fungus.

  2. Leptographium tereforme sp. nov. and other Ophiostomatales isolated from the root-feeding bark beetle, Hylurgus ligniperda, in California

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The redhaired pine bark beetle, Hylurgus ligniperda F., is native to Europe but was discovered in Los Angeles, California in 2003. This root- and stump-feeding bark beetle is a common vector of Ophiostomatales, which are potential tree pathogens or causes of blue-stain of conifer sapwood. In this st...

  3. Semiochemical-MediatedFlight Strategies of Two Invasive Elm Bark Beetles: A Potential Factor in Competitive Displacement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent seven-state survey revealed that the newly invasive banded elm bark beetle, Scolytus schevyrewi, was abundant in areas of Colorado and Wyoming, USA, whereas the long-established European elm bark beetle, S. multistriatus was not as abundant. Behavioral trials were conducted by hanging sm...

  4. 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.

  5. Coordinated gene expression for pheromone biosynthesis in the pine engraver beetle, Ips pini (Coleoptera: Scolytidae)

    NASA Astrophysics Data System (ADS)

    Keeling, Christopher I.; Blomquist, Gary J.; Tittiger, Claus

    In several pine bark beetle species, phloem feeding induces aggregation pheromone production to coordinate a mass attack on the host tree. Male pine engraver beetles, Ips pini (Say) (Coleoptera: Scolytidae), produce the monoterpenoid pheromone component ipsdienol de novo via the mevalonate pathway in the anterior midgut upon feeding. To understand how pheromone production is regulated in this tissue, we used quantitative real-time PCR to examine feeding-induced changes in gene expression of seven mevalonate pathway genes: acetoacetyl-coenzyme A thiolase, 3-hydroxy-3-methylglutaryl coenzyme A synthase, 3-hydroxy-3-methylglutaryl coenzyme A reductase, mevalonate 5-diphosphate decarboxylase, isopentenyl-diphosphate isomerase, geranyl-diphosphate synthase (GPPS), and farnesyl-diphosphate synthase (FPPS). In males, expression of all these genes significantly increased upon feeding. In females, the expression of the early mevalonate pathway genes (up to and including the isomerase) increased significantly, but the expression of the later genes (GPPS and FPPS) was unaffected or decreased upon feeding. Thus, feeding coordinately regulates expression of the mevalonate pathway genes necessary for pheromone biosynthesis in male, but not female, midguts. Furthermore, basal mRNA levels were 5- to 41-fold more abundant in male midguts compared to female midguts. This is the first report of coordinated regulation of mevalonate pathway genes in an invertebrate model consistent with their sex-specific role in de novo pheromone biosynthesis.

  6. Strategies of a bark beetle, Pityogenes bidentatus, in an olfactory landscape.

    PubMed

    Byers, J A; Zhang, Q H; Birgersson, G

    2000-11-01

    Volatiles from leaves or bark of nonhost birch (Betula pendula) and Norway spruce (Picea abies) dramatically reduced the attraction of the bark beetle, Pityogenes bidentatus (Coleoptera: Scolytidae), to their aggregation pheromone components (cis-verbenol and grandisol) in the field. In addition, odors from both the needles and bark of the host Scots pine (Pinus sylvestris) similarly inhibited attraction. Monoterpenes of pine and spruce (alpha-pinene, beta-pinene, terpinolene, and 3-carene) as well as ethanol, chalcogran and some nonhost green leaf alcohols [(Z)-3-hexen-1-ol, (E)-2-hexen-1-ol, and 1-hexanol], also reduced catches. Collections of volatiles from the field-tested plant tissues indicated they released monoterpenes in amounts similar to the synthetics that inhibited responses. The various plant and insect sources of these inhibitory compounds indicate that P. bidentatus bark beetles have evolved several strategies to increase their fitness by avoiding nonhost and unsuitable host trees in a complex olfactory landscape.

  7. 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.

  8. 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.

  9. 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.

  10. Resin duct characteristics associated with tree resistance to bark beetles across lodgepole and limber pines.

    PubMed

    Ferrenberg, Scott; Kane, Jeffrey M; Mitton, Jeffry B

    2014-04-01

    Bark beetles have recently killed billions of trees, yet conifer defenses are formidable and some trees resist attack. A primary anti-insect defense of pines is oleoresin from a system of resin ducts throughout the tree. Resin defense traits are heritable, and evidence suggests that resin duct characteristics are associated with resistance to insects. However, comparisons of resin ducts in trees killed by bark beetles to trees that resisted attack are unavailable. We compared vertical resin duct characteristics (number, density, and size) and growth rates from trees that were "resistant" (survived mass attack) versus "susceptible" (killed by attack) to bark beetles in lodgepole (Pinus contorta) and limber (Pinus flexilis) pines. Resistant trees of both species had significantly more resin ducts in recent growth than susceptible trees. Discriminant analysis (DA) correctly categorized 84% of lodgepole and 92% of limber pines as susceptible/resistant based on combinations of resin duct and growth characteristics from recent 5- through 20-year growth intervals. DA models using measures from only the most recent 5 years of growth correctly categorized 72 and 81% of lodgepole and limber pines, respectively. Comparing resistant to susceptible trees independent of species identity led to the correct categorization of 82% of trees based on factors from 5- to 20-year intervals, and 73% of trees using only resin duct counts from the most recent 5 years. We conclude that resin duct characteristics can be used to assess tree resistance to bark beetles across pine species, and offer a metric for management to enhance pest resistance.

  11. Are bark beetles chewing up our forests? What about our coffee?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A write-up for the Elsevier SciTech Connect blog on the recently published book entitled "Bark Beetles: Biology and Ecology of Native and Invasive Species," edited by Fernando E. Vega and Richard W. Hofstetter. The book was published by Academic Press in January 2015....

  12. Broadscale specificity in a bark beetle-fungal symbiosis: a spatio-temporal analysis of the mycangial fungi of the western pine beetle.

    PubMed

    Bracewell, Ryan R; Six, Diana L

    2014-11-01

    Whether and how mutualisms are maintained through ecological and evolutionary time is a seldom studied aspect of bark beetle-fungal symbioses. All bark beetles are associated with fungi and some species have evolved structures for transporting their symbiotic partners. However, the fungal assemblages and specificity in these symbioses are not well known. To determine the distribution of fungi associated with the mycangia of the western pine beetle (Dendroctonus brevicomis), we collected beetles from across the insect's geographic range including multiple genetically distinct populations. Two fungi, Entomocorticium sp. B and Ceratocystiopsis brevicomi, were isolated from the mycangia of beetles from all locations. Repeated sampling at two sites in Montana found that Entomocorticium sp. B was the most prevalent fungus throughout the beetle's flight season, and that females carrying that fungus were on average larger than females carrying C. brevicomi. We present evidence that throughout the flight season, over broad geographic distances, and among genetically distinct populations of beetle, the western pine beetle is associated with the same two species of fungi. In addition, we provide evidence that one fungal species is associated with larger adult beetles and therefore might provide greater benefit during beetle development. The importance and maintenance of this bark beetle-fungus interaction is discussed.

  13. Presence and diversity of Streptomyces in Dendroctonus and sympatric bark beetle galleries across North America.

    PubMed

    Hulcr, Jiri; Adams, Aaron S; Raffa, Kenneth; Hofstetter, Richard W; Klepzig, Kier D; Currie, Cameron R

    2011-05-01

    Recent studies have revealed several examples of intimate associations between insects and Actinobacteria, including the Southern Pine Beetle Dendroctonus frontalis and the Spruce Beetle Dendroctonus rufipennis. Here, we surveyed Streptomyces Actinobacteria co-occurring with 10 species of Dendroctonus bark beetles across the United States, using both phylogenetic and community ecology approaches. From these 10 species, and 19 other scolytine beetles that occur in the same trees, we obtained 154 Streptomyces-like isolates and generated 16S sequences from 134 of those. Confirmed 16S sequences of Streptomyces were binned into 36 distinct strains using a threshold of 0.2% sequence divergence. The 16S rDNA phylogeny of all isolates does not correlate with the distribution of strains among beetle species, localities, or parts of the beetles or their galleries. However, we identified three Streptomyces strains occurring repeatedly on Dendroctonus beetles and in their galleries. Identity of these isolates was corroborated using a house-keeping gene sequence (efTu). These strains are not confined to a certain species of beetle, locality, or part of the beetle or their galleries. However, their role as residents in the woodboring insect niche is supported by the repeated association of their 16S and efTu from across the continent, and also having been reported in studies of other subcortical insects.

  14. 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.

  15. Large carbon release legacy from bark beetle outbreaks across Western United States.

    PubMed

    Ghimire, Bardan; Williams, Christopher A; Collatz, G James; Vanderhoof, Melanie; Rogan, John; Kulakowski, Dominik; Masek, Jeffrey G

    2015-08-01

    Warmer conditions over the past two decades have contributed to rapid expansion of bark beetle outbreaks killing millions of trees over a large fraction of western United States (US) forests. These outbreaks reduce plant productivity by killing trees and transfer carbon from live to dead pools where carbon is slowly emitted to the atmosphere via heterotrophic respiration which subsequently feeds back to climate change. Recent studies have begun to examine the local impacts of bark beetle outbreaks in individual stands, but the full regional carbon consequences remain undocumented for the western US. In this study, we quantify the regional carbon impacts of the bark beetle outbreaks taking place in western US forests. The work relies on a combination of postdisturbance forest regrowth trajectories derived from forest inventory data and a process-based carbon cycle model tracking decomposition, as well as aerial detection survey (ADS) data documenting the regional extent and severity of recent outbreaks. We find that biomass killed by bark beetle attacks across beetle-affected areas in western US forests from 2000 to 2009 ranges from 5 to 15 Tg C yr(-1) and caused a reduction of net ecosystem productivity (NEP) of about 6.1-9.3 Tg C y(-1) by 2009. Uncertainties result largely from a lack of detailed surveys of the extent and severity of outbreaks, calling out a need for improved characterization across western US forests. The carbon flux legacy of 2000-2009 outbreaks will continue decades into the future (e.g., 2040-2060) as committed emissions from heterotrophic respiration of beetle-killed biomass are balanced by forest regrowth and accumulation.

  16. Spatial variability in tree regeneration after wildfire delays and dampens future bark beetle outbreaks.

    PubMed

    Seidl, Rupert; Donato, Daniel C; Raffa, Kenneth F; Turner, Monica G

    2016-11-15

    Climate change is altering the frequency and severity of forest disturbances such as wildfires and bark beetle outbreaks, thereby increasing the potential for sequential disturbances to interact. Interactions can amplify or dampen disturbances, yet the direction and magnitude of future disturbance interactions are difficult to anticipate because underlying mechanisms remain poorly understood. We tested how variability in postfire forest development affects future susceptibility to bark beetle outbreaks, focusing on mountain pine beetle (Dendroctonus ponderosae) and Douglas-fir beetle (Dendroctonus pseudotsugae) in forests regenerating from the large high-severity fires that affected Yellowstone National Park in Wyoming in 1988. We combined extensive field data on postfire tree regeneration with a well-tested simulation model to assess susceptibility to bark beetle outbreaks over 130 y of stand development. Despite originating from the same fire event, among-stand variation in forest structure was very high and remained considerable for over a century. Thus, simulated emergence of stands susceptible to bark beetles was not temporally synchronized but was protracted by several decades, compared with stand development from spatially homogeneous regeneration. Furthermore, because of fire-mediated variability in forest structure, the habitat connectivity required to support broad-scale outbreaks and amplifying cross-scale feedbacks did not develop until well into the second century after the initial burn. We conclude that variability in tree regeneration after disturbance can dampen and delay future disturbance by breaking spatiotemporal synchrony on the landscape. This highlights the importance of fostering landscape variability in the context of ecosystem management given changing disturbance regimes.

  17. Linking increasing drought stress to Scots pine mortality and bark beetle infestations.

    PubMed

    Dobbertin, Matthias; Wermelinger, Beat; Bigler, Christof; Bürgi, Matthias; Carron, Mathias; Forster, Beat; Gimmi, Urs; Rigling, Andreas

    2007-03-21

    In the dry Swiss Rhone Valley, Scots pine forests have experienced increased mortality in recent years. It has commonly been assumed that drought events and bark beetles fostered the decline, however, whether bark beetle outbreaks increased in recent years and whether they can be linked to drought stress or increasing temperature has never been studied. In our study, we correlated time series of drought indices from long-term climate stations, 11-year mortality trends from a long-term research plot, and mortality probabilities modeled from tree rings (as an indicator of tree vitality) with documented occurrences of various bark beetle species and a buprestid beetle, using regional Forest Service reports from 1902 to 2003 and advisory cases of the Swiss Forest Protection Service (SFPS) from 1984 to 2005. We compared the historical findings with measured beetle emergence from a 4-year tree felling and breeding chamber experiment. The documented beetle-related pine mortality cases increased dramatically in the 1990s, both in the forest reports and the advisory cases. The incidents of beetle-related pine mortality correlated positively with spring and summer temperature, and with the tree-ring based mortality index, but not with the drought index. The number of advisory cases, on the other hand, correlated slightly with summer drought index and temperature, but very highly with tree-ring-based mortality index. The tree-ring-based mortality index and observed tree mortality increased in years following drought. This was confirmed by the beetle emergences from felled trees. Following dry summers, more than twice as many trees were colonized by beetles than following wet summers. We conclude that increased temperatures in the Swiss Rhone Valley have likely weakened Scots pines and favored phloeophagous beetle population growth. Beetles contributed to the increased pine mortality following summer drought. Among the factors not addressed in this study, changed forest use

  18. Ophiostoma ips from Pinewood Nematode Vector, Japanese Pine Sawyer Beetle (Monochamus alternatus), in Korea.

    PubMed

    Suh, Dong Yeon; Hyun, Min Woo; Kim, Jae Jin; Son, Seung Yeol; Kim, Seong Hwan

    2013-03-01

    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.

  19. 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

  20. Geosmithia fungi are highly diverse and consistent bark beetle associates: evidence from their community structure in temperate Europe.

    PubMed

    Kolarík, Miroslav; Kubátová, Alena; Hulcr, Jirí; Pazoutová, Sylvie

    2008-01-01

    Geosmithia spp. (Ascomycota: Hypocreales) are little-studied, dry-spored fungi that occur in galleries built by many phloeophagous bark beetles. This study mapped the distribution and environmental preferences of Geosmithia species occurring in galleries of temperate European bark beetles. One hundred seven host tree samples of 16 tree species infested with 23 subcortical insect species were collected from across Europe during the years 1997-2005. Over 600 Geosmithia isolates from the beetles were sorted into 17 operational taxonomic units (OTUs) based on their phenotype similarity and phylogeny of internal transcribed spacer (ITS) region of rDNA (ITS1-5.8S-ITS2). The OTUs represent six known species and eight undescribed taxa. Ninety-two samples infested with subcortical insects were characterized by the presence/absence of OTUs and the similarity among the samples was evaluated. Geographically distant populations of the same beetle species host relatively uniform Geosmithia communities across large geographic areas (ranging from southern Bulgaria to the Czech Republic). This suggests effective dispersal of Geosmithia spp. by bark beetles. Clustering of similar samples in ordination analysis is correlated predominantly with the isolation source (bark beetles and their respective feeding plant), but not with their geographical origin. The composition of the Geosmithia OTU community of each bark beetle species depends on the degree of isolation of the species' niches. Thus, Geosmithia communities associated with regularly co-occurring bark beetle species are highly similar. The similarity decreases with decreasing frequency of beetle species' co-occurrence, a pattern resembling that of entomochoric ophiostomatoid fungi. These findings suggest that: 1) communities of Geosmithia spp. are vector-specific; 2) at least in some cases, the association between Geosmithia OTUs and bark beetles may have been very stable and symbioses are likely to be a fundamental factor in

  1. Avoidance of nonhost plants by a bark beetle, Pityogenes bidentatus, in a forest of odors

    NASA Astrophysics Data System (ADS)

    Byers, John A.; Zhang, Qing-He; Birgersson, Göran

    The bark beetle, Pityogenes bidentatus (Coleoptera: Scolytidae), searches in mixed conifer and deciduous forests of northern Europe for suitable branches of its host, Scots pine (Pinus sylvestris). We tested whether odors from several diverse nonhost trees and plants common in the habitat (e.g., mountain ash, Sorbus aucuparia; oak, Quercus robur; alder buckthorn, Frangula alnus; blueberry, Vaccinium myrtillus; raspberry, Rubus idaeus; and grass, Deschampsia flexuosa) would reduce the attraction of the bark beetle to traps releasing its aggregation pheromone components in the field. Volatiles from the leaves or bark of each of these plants significantly reduced the attraction of the beetles to their pheromone. Odors collected from these nonhosts and analyzed by GC/MS contained monoterpenes, sesquiterpenes, and ``green-leaf'' alcohols, several of which (e.g., 1-octene-3-ol and β-caryophyllene) reduced the attraction to pheromone in the field and elicited electroantennographic responses. In the laboratory, reproduction by the beetle was marginal in nonhost Norway spruce, Picea abies, and was absent in the other nonhost trees. Olfactory avoidance of unsuitable nonhosts may have evolved due to advantages in avoiding mistakes during host selection.

  2. The Bark-Beetle-Associated Fungus, Endoconidiophora polonica, Utilizes the Phenolic Defense Compounds of Its Host as a Carbon Source1[OPEN

    PubMed Central

    Wadke, Namita; Kandasamy, Dineshkumar; Vogel, Heiko; Wingfield, Brenda D.; Paetz, Christian

    2016-01-01

    Norway spruce (Picea abies) is periodically attacked by the bark beetle Ips typographus and its fungal associate, Endoconidiophora polonica, whose infection is thought to be required for successful beetle attack. Norway spruce produces terpenoid resins and phenolics in response to fungal and bark beetle invasion. However, how the fungal associate copes with these chemical defenses is still unclear. In this study, we investigated changes in the phenolic content of Norway spruce bark upon E. polonica infection and the biochemical factors mediating these changes. Although genes encoding the rate-limiting enzymes in Norway spruce stilbene and flavonoid biosynthesis were actively transcribed during fungal infection, there was a significant time-dependent decline of the corresponding metabolites in fungal lesions. In vitro feeding experiments with pure phenolics revealed that E. polonica transforms both stilbenes and flavonoids to muconoid-type ring-cleavage products, which are likely the first steps in the degradation of spruce defenses to substrates that can enter the tricarboxylic acid cycle. Four genes were identified in E. polonica that encode catechol dioxygenases carrying out these reactions. These enzymes catalyze the cleavage of phenolic rings with a vicinal dihydroxyl group to muconoid products accepting a wide range of Norway spruce-produced phenolics as substrates. The expression of these genes and E. polonica utilization of the most abundant spruce phenolics as carbon sources both correlated positively with fungal virulence in several strains. Thus, the pathways for the degradation of phenolic compounds in E. polonica, initiated by catechol dioxygenase action, are important to the infection, growth, and survival of this bark beetle-vectored fungus and may play a major role in the ability of I. typographus to colonize spruce trees. PMID:27208235

  3. 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.

  4. 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

  5. Bark Beetles as Significant Forest Disturbances: Estimating Susceptibility Based On Stand Structure

    NASA Astrophysics Data System (ADS)

    Hicke, J. A.; Jenkins, J. C.

    2007-12-01

    In the western United States, bark beetle outbreaks affect millions of hectares of forests. These disturbances have multiple effects on ecosystems, including modifications to biogeochemical cycles, interactions with fire, and changes in land cover type and species composition. In recent years, extensive outbreaks have occurred in multiple forest ecosystems in the West, thought to be caused by climate variability and stand structure. In this study, we focus on epidemics of mountain pine beetle. We used USDA Forest Service inventories and a model to estimate lodgepole pine susceptibility to mountain pine beetle attack in the West. The model considers stand age, stem density, and percentage of large lodgepole pine to estimate stand susceptibility. Over 150,000 trees in 4454 plots across the western United States were used to compute susceptibility at the plot scale as well as map susceptibility at the county scale. We found that regional susceptibility was high (estimated potential of losses of 34% of stand basal area) for 2.8 Mha, or 46%, of lodgepole pine forests. The highest susceptibility occurred in the Rocky Mountains, with lower susceptibility in coastal states. This study reveals that a substantial fraction of lodgepole pine forest could be subjected to bark beetle outbreaks under current climate conditions. Because climate and weather affect beetle populations, projected future warming will influence outbreak regimes. Thus, forest ecosystems in the West may experience more frequent, extensive, and/or severe disturbances than in recent decades due to current stand structure, and these disturbances may be intensified under climate change.

  6. 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.

  7. Ecological and Evolutionary Determinants of Bark Beetle —Fungus Symbioses

    PubMed Central

    Six, Diana L.

    2012-01-01

    Ectosymbioses among bark beetles (Curculionidae, Scolytinae) and fungi (primarily ophiostomatoid Ascomycetes) are widespread and diverse. Associations range from mutualistic to commensal, and from facultative to obligate. Some fungi are highly specific and associated only with a single beetle species, while others can be associated with many. In addition, most of these symbioses are multipartite, with the host beetle associated with two or more consistent partners. Mycangia, structures of the beetle integument that function in fungal transport, have evolved numerous times in the Scolytinae. The evolution of such complex, specialized structures indicates a high degree of mutual dependence among the beetles and their fungal partners. Unfortunately, the processes that shaped current day beetle-fungus symbioses remain poorly understood. Phylogeny, the degree and type of dependence on partners, mode of transmission of symbionts (vertical vs. horizontal), effects of the abiotic environment, and interactions among symbionts themselves or with other members of the biotic community, all play important roles in determining the composition, fidelity, and longevity of associations between beetles and their fungal associates. In this review, I provide an overview of these associations and discuss how evolution and ecological processes acted in concert to shape these fascinating, complex symbioses. PMID:26467964

  8. Aggregation pheromones of bark beetles, pityogenes quadridens and P. bidentatus, colonizing scotch pine: olfactory avoidance of interspecific competition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The bark beetles Pityogenes bidentatus and P. quadridens (Coleoptera, Curculionidae, Scolytinae) compete for bark areas on branches of Scotch pine, Pinus sylvestris. Hindguts and head/thoraxes of males and females of both species feeding in hosts were extracted in pentane and analyzed by gas chromat...

  9. Biology of the invasive banded elm bark beetle, Scolytus schevyrewi Semenov (Coleoptera: Scolytidae), in the western United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The invasive banded elm bark beetle, Scolytus schevyrewi Semenov, native to Asia, was detected in the United States in 2003 and is now known to occur in 28 states and four Canadian Provinces. S. schevyrewi infests the same elm hosts as the long-established invasive, and smaller European elm bark be...

  10. Seasonal Succession of Fungi Associated with Ips typographus Beetles and Their Phoretic Mites in an Outbreak Region of Finland

    PubMed Central

    Mahilainen, Saila; Harrington, Alison; Vanhanen, Henri; Eriksson, Miikka; Mehtätalo, Lauri; Pappinen, Ari; Wingfield, Michael J.

    2016-01-01

    The ophiostomatoid fungi (Microascales and Ophiostomatales, Ascomycota) are common associates of Ips typographus, and include tree pathogens and species responsible for blue-stain of timber. Fungal assemblages associated with I. typographus have varied considerably between studies but few investigations have attempted to explain this variation. For this reason, we assessed the overall cultivable fungal diversity associated with I. typographus in a storm-felled spruce forest in south-eastern Finland. Fungi were isolated from the individually collected beetles as well as their phoretic mites in spring, summer and autumn, including different life stages of the beetle (hibernation, dispersal flight and first generation). The internal transcribed spacer (ITS) gene region was used to identify the fungi. A total of 32 operational taxonomic units (OTUs) were found and these resided in four fungal phyla/subphyla (24 Ascomycota, 2 Basidiomycota, 5 Mucoromycotina, 1 Mortierellomycotina) in association with adult bark beetles. Ophiostomatoid species were the most commonly detected fungal associates. A generalized linear model analysis showed a clear association between fungal communities and season, indicating seasonal succession among I. typographus-associated fungi. The season of sampling appears to be an important factor that has resulted in inconsistencies between results in previous studies. Many of these fungi were also found on phoretic mites and their presence or absence could have influenced variation in patterns of association. PMID:27187192

  11. Importance of resin ducts in reducing ponderosa pine mortality from bark beetle attack.

    PubMed

    Kane, Jeffrey M; Kolb, Thomas E

    2010-11-01

    The relative importance of growth and defense to tree mortality during drought and bark beetle attacks is poorly understood. We addressed this issue by comparing growth and defense characteristics between 25 pairs of ponderosa pine (Pinus ponderosa) trees that survived and trees that died from drought-associated bark beetle attacks in forests of northern Arizona, USA. The three major findings of our research were: (1) xylem resin ducts in live trees were >10% larger (diameter), >25% denser (no. of resin ducts mm(-2)), and composed >50% more area per unit ring growth than dead trees; (2) measures of defense, such as resin duct production (no. of resin ducts year(-1)) and the proportion of xylem ring area to resin ducts, not growth, were the best model parameters of ponderosa pine mortality; and (3) most correlations between annual variation in growth and resin duct characteristics were positive suggesting that conditions conducive to growth also increase resin duct production. Our results suggest that trees that survive drought and subsequent bark beetle attacks invest more carbon in resin defense than trees that die, and that carbon allocation to resin ducts is a more important determinant of tree mortality than allocation to radial growth.

  12. Impacts of Bark Beetle Outbreaks in the Western US on Biogeochemical Cycling

    NASA Astrophysics Data System (ADS)

    Hicke, J. A.; Edburg, S. L.; Meddens, A. J.

    2011-12-01

    Insect outbreaks are major forest disturbances, altering carbon and nitrogen fluxes through growth reductions and/or tree mortality. In western North America, bark beetles have killed trees over millions of hectares. Here we report on several studies that increase our understanding of the biogeochemical impacts of bark beetle epidemics. We modified the Community Land Model to simulate these disturbances, then ran the model for a range of hypothetical, realistic outbreak conditions to explore variability in impacts. We find significant differences in the responses of carbon and nitrogen based on the severity of the outbreak, the timing of snagfall, and the time since attack. Given the importance of identifying the number of trees killed within a study region for accurately quantifying impacts, we have developed a database of mortality in the western US and British Columbia for 1997-2009. We combined this database with spatially explicit maps of carbon stocks to estimate the amount of carbon in killed trees. We also used this database to drive CLM to quantify changes in biogeochemical stocks and fluxes. We find that in some regions, bark beetle-killed trees accounted for over 30% of the carbon stocks, whereas in other areas, the number of killed trees was low. Effects on net carbon fluxes in outbreak regions were significant, with fluxes switching from sinks to sources.

  13. Comparative multilocus phylogeography of two Palaearctic spruce bark beetles: influence of contrasting ecological strategies on genetic variation.

    PubMed

    Mayer, François; Piel, Frédéric B; Cassel-Lundhagen, Anna; Kirichenko, Natalia; Grumiau, Laurent; Økland, Bjørn; Bertheau, Coralie; Grégoire, Jean-Claude; Mardulyn, Patrick

    2015-03-01

    While phylogeographic patterns of organisms are often interpreted through past environmental disturbances, mediated by climate changes, and geographic barriers, they may also be strongly influenced by species-specific traits. To investigate the impact of such traits, we focused on two Eurasian spruce bark beetles that share a similar geographic distribution, but differ in their ecology and reproduction. Ips typographus is an aggressive tree-killing species characterized by strong dispersal, whereas Dendroctonus micans is a discrete inbreeding species (sib mating is the rule), parasite of living trees and a poor disperser. We compared genetic variation between the two species over both beetles' entire range in Eurasia with five independent gene fragments, to evaluate whether their intrinsic differences could have an influence over their phylogeographic patterns. We highlighted widely divergent patterns of genetic variation for the two species and argue that the difference is indeed largely compatible with their contrasting dispersal strategies and modes of reproduction. In addition, genetic structure in I. typographus divides European populations in a northern and a southern group, as was previously observed for its host plant, and suggests past allopatric divergence. A long divergence time was estimated between East Asian and other populations of both species, indicating their long-standing presence in Eurasia, prior to the last glacial maximum. Finally, the strong population structure observed in D. micans for the mitochondrial locus provides insights into the recent colonization history of this species, from its native European range to regions where it was recently introduced.

  14. A new approach to determine the capture conditions of bark beetles in pheromone-baited traps

    PubMed Central

    Ozcan, Gonca Ece; Cicek, Osman; Enez, Korhan; Yildiz, Mustafa

    2014-01-01

    Forests form an organic unity with a great number of organic and inorganic components and tend to maintain the sustainability of their existing balance. However, some factors which adversely affect the balance of nature may interrupt this sustainability. The epidemic which is formed by bark beetles in their spreading region, due to various factors, changes the stability so much that interference is required. One of the most common methods used to monitor these beetles is pheromone-baited traps. The recognition of parameters, such as date (day/month/year), temperature and humidity, when bark beetles are captured in pheromone-baited traps, especially those used for monitoring will help to increase the trap efficiency on land and to develop an effective strategy for combating pests. In this study, an electronic control unit was added to pheromone-baited traps in order to obtain all of the above mentioned parameters. This unit operates with microcontrollers and data related to the parameters is saved in a storage unit. This is triggered by the beetle at the moment it is captured in the trap. A photovoltaic system was used to meet the energy needed for the system functioning and to complete the counting process in due time. PMID:26019592

  15. Preferential host switching and codivergence shaped radiation of bark beetle symbionts, nematodes of Micoletzkya (Nematoda: Diplogastridae).

    PubMed

    Susoy, V; Herrmann, M

    2014-05-01

    Host-symbiont systems are of particular interest to evolutionary biology because they allow testable inferences of diversification processes while also providing both a historical basis and an ecological context for studies of adaptation. Our investigations of bark beetle symbionts, predatory nematodes of the genus Micoletzkya, have revealed remarkable diversity of the group along with a high level of host specificity. Cophylogenetic analyses suggest that evolution of the nematodes was largely influenced by the evolutionary history of beetles. The diversification of the symbionts, however, could not be attributed to parallel divergence alone; our results indicate that adaptive radiation of the nematodes was shaped by preferential host shifts among closely related beetles along with codivergence. Whereas ecological and geographic isolation have played a major role in the diversification of Micoletzkya at shallow phylogenetic depths, adaptations towards related hosts have played a role in shaping cophylogenetic structure at a larger evolutionary scale.

  16. Host range and diversity of the genus Geosmithia (Ascomycota: Hypocreales) living in association with bark beetles in the Mediterranean area.

    PubMed

    Kolarík, Miroslav; Kostovcík, Martin; Pazoutová, Sylvie

    2007-11-01

    Geosmithia spp. (Ascomycota: Hypocreales) are dry-spored fungi that occur in galleries built by many phloeophagous bark beetles. This study mapped the diversity, host spectrum and area of distribution of Geosmithia spp. occurring in galleries of bark beetle species with a Mediterranean distribution. Eighty-six wood samples of 19 tree species infested by 18 subcortical insect species were collected from across the Mediterranean Basin during the years 2003-2006. Geosmithia spp. were found in 82 samples of angiosperms and two host trees from the family Juniperaceae infested by 14 bark beetles and the bostrichid Scobicia pustulata, suggesting that the association of Geosmithia and phloeophagous bark beetles is very widespread in the Mediterranean. Geosmithia isolates were sorted into 13 operational taxonomic units (OTUs) based on their phenotype similarity and phylogeny of their ITS regions of rDNA (ITS1-5.8S-ITS2). The OTUs represent five known species (G. flava, G. langdonii, G. lavendula, G. pallida, G. putterillii) and seven undescribed taxa. Most of the bark beetles were associated with on average 1-2.5 OTUs per sample. G. lavendula, considered very uncommon in nature, was found as a common associate of bark beetles. Six out of 13 OTUs were found to be distributed in the Mediterranean but not in neighbouring areas of temperate Europe suggesting that Geosmithia spp. have a geographically limited distribution, probably due to their dependency on the geographically limited area of their vectors. The proportion of generalists and specialists among Geosmithia spp. was smaller compared with data from temperate Europe. A possible explanation is the effective dispersal of Geosmithia by polyphagous bostrichids across the niches defined by mutually exclusive bark beetles.

  17. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    USGS Publications Warehouse

    Hicke, Jeffrey A.; Meddens, Arjan J.H.; Allen, Craig D.; Kolden, Crystal A.

    2013-01-01

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.

  18. Carbon stocks of trees killed by bark beetles and wildfire in the western United States

    NASA Astrophysics Data System (ADS)

    Hicke, Jeffrey A.; Meddens, Arjan J. H.; Allen, Craig D.; Kolden, Crystal A.

    2013-09-01

    Forests are major components of the carbon cycle, and disturbances are important influences of forest carbon. Our objective was to contribute to the understanding of forest carbon cycling by quantifying the amount of carbon in trees killed by two disturbance types, fires and bark beetles, in the western United States in recent decades. We combined existing spatial data sets of forest biomass, burn severity, and beetle-caused tree mortality to estimate the amount of aboveground and belowground carbon in killed trees across the region. We found that during 1984-2010, fires killed trees that contained 5-11 Tg C year-1 and during 1997-2010, beetles killed trees that contained 2-24 Tg C year-1, with more trees killed since 2000 than in earlier periods. Over their periods of record, amounts of carbon in trees killed by fires and by beetle outbreaks were similar, and together these disturbances killed trees representing 9% of the total tree carbon in western forests, a similar amount to harvesting. Fires killed more trees in lower-elevation forest types such as Douglas-fir than higher-elevation forest types, whereas bark beetle outbreaks also killed trees in higher-elevation forest types such as lodgepole pine and Engelmann spruce. Over 15% of the carbon in lodgepole pine and spruce/fir forest types was in trees killed by beetle outbreaks; other forest types had 5-10% of the carbon in killed trees. Our results document the importance of these natural disturbances in the carbon budget of the western United States.

  19. Life and death of Picea abies after bark-beetle outbreak: ecological processes driving seedling recruitment.

    PubMed

    Macek, Martin; Wild, Jan; Kopecký, Martin; Červenka, Jaroslav; Svoboda, Miroslav; Zenáhlíková, Jitka; Brůna, Josef; Mosandl, Reinhard; Fischer, Anton

    2017-01-01

    The severity and spatial extent of bark-beetle outbreaks substantially increased in recent decades worldwide. The ongoing controversy about natural forest recovery after these outbreaks highlights the need for individual-based long-term studies, which disentangle processes driving forest regeneration. However, such studies have been lacking. To fill this gap, we followed the fates of 2,552 individual seedlings for 12 years after a large-scale bark-beetle outbreak that caused complete canopy dieback in mountain Norway spruce (Picea abies) forests in southeast Germany. We explore the contribution of advance, disturbance-related, and post-disturbance regeneration to forest recovery. Most seedlings originated directly within the three-year dieback of canopy trees induced by bark-beetle outbreak. After complete canopy dieback, the establishment of new seedlings was minimal. Surprisingly, advance regeneration formed only a minor part of all regeneration. However, because it had the highest survival rate, its importance increased over time. The most important factor influencing the survival of seedlings after disturbance was their height. Survival was further modified by microsite: seedlings established on dead wood survived best, whereas almost all seedlings surrounded by graminoids died. For 5 cm tall seedlings, annual mortality ranged from 20 to 50% according to the rooting microsite. However, for seedlings taller than 50 cm, annual mortality was below 5% at all microsites. While microsite modified seedling mortality, it did not affect seedling height growth. A model of regeneration dynamics based on short-term observations accurately predicts regeneration height growth, but substantially underestimates mortality rate, thus predicting more surviving seedlings than were observed. We found that P. abies forests were able to regenerate naturally even after severe bark-beetle outbreaks owing to advance and particularly disturbance-related regeneration. This, together

  20. 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.

  1. Catchment response to bark beetle outbreak and dust-on-snow in the Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Livneh, Ben; Deems, Jeffrey S.; Buma, Brian; Barsugli, Joseph J.; Schneider, Dominik; Molotch, Noah P.; Wolter, K.; Wessman, Carol A.

    2015-04-01

    Since 2002, the headwaters of the Colorado River and nearby basins have experienced extensive changes in land cover at sub-annual timescales. Widespread tree mortality from bark beetle infestation has taken place across a range of forest types, elevation, and latitude. Extent and severity of forest structure alteration have been observed through a combination of aerial survey, satellite remote-sensing, and in situ measurements. Additional perturbations have resulted from deposition of dust from regional dry-land sources on mountain snowpacks that strongly alter the snow surface albedo, driving earlier and faster snowmelt runoff. One challenge facing past studies of these forms of disturbance is the relatively small magnitude of the disturbance signals within the larger climatic signal. The combined impacts of forest disturbance and dust-on-snow are explored within a hydrologic modeling framework. We drive the Distributed Hydrology Soil and Vegetation Model (DHSVM) with observed meteorological data, time-varying maps of leaf area index and forest properties to emulate bark beetle impacts, and parameterizations of snow albedo based on observations of dust forcing. Results from beetle-killed canopy alteration suggest slightly greater snow accumulation as a result of less interception and reduced canopy sublimation and evapotranspiration, contributing to overall increases in annual water yield between 8% and 13%. However, understory regeneration roughly halves the changes in water yield. A purely observation-based estimate of runoff coefficient change with cumulative forest mortality shows comparable sensitivities to simulated results; however, positive water yield changes are not statistically significant (p ⩽ 0.05). The primary hydrologic impact of dust-on-snow forcing is an increased rate of snowmelt associated with more extreme dust deposition, producing earlier peak streamflow rates on the order of 1-3 weeks. Simulations of combined bark beetle and dust

  2. Genomic Mining of Phylogenetically Informative Nuclear Markers in Bark and Ambrosia Beetles

    PubMed Central

    Pistone, Dario; Mugu, Sigrid; Jordal, Bjarte Henry

    2016-01-01

    Deep level insect relationships are generally difficult to resolve, especially within taxa of the most diverse and species rich holometabolous orders. In beetles, the major diversity occurs in the Phytophaga, including charismatic groups such as leaf beetles, longhorn beetles and weevils. Bark and ambrosia beetles are wood boring weevils that contribute 12 percent of the diversity encountered in Curculionidae, one of the largest families of beetles with more than 50000 described species. Phylogenetic resolution in groups of Cretaceous age has proven particularly difficult and requires large quantity of data. In this study, we investigated 100 nuclear genes in order to select a number of markers with low evolutionary rates and high phylogenetic signal. A PCR screening using degenerate primers was applied to 26 different weevil species. We obtained sequences from 57 of the 100 targeted genes. Sequences from each nuclear marker were aligned and examined for detecting multiple copies, pseudogenes and introns. Phylogenetic informativeness (PI) and the capacity for reconstruction of previously established phylogenetic relationships were used as proxies for selecting a subset of the 57 amplified genes. Finally, we selected 16 markers suitable for large-scale phylogenetics of Scolytinae and related weevil taxa. PMID:27668729

  3. Host Acceptance and Larval Competition between the Invasive Banded and European Elm Bark Beetles, Scolytus schevyrewi and S. multistriatus (Coleoptera: Scolytidae): Potential Mechanisms for Competitive Displacement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent survey revealed that the newly invasive banded elm bark beetle, Scolytus schevyrewi, was much more abundant than the long-established European elm bark beetle, S. multistriatus, in areas of Colorado and Wyoming, USA. This study sought to determine whether competitive displacement of S. mul...

  4. Colonization of Artificially Stressed Black Walnut Trees by Ambrosia Beetle, Bark Beetle, and Other Weevil Species (Coleoptera: Curculionidae) in Indiana and Missouri.

    PubMed

    Reed, Sharon E; Juzwik, Jennifer; English, James T; Ginzel, Matthew D

    2015-12-01

    Thousand cankers disease (TCD) is a new disease of black walnut (Juglans nigra L.) in the eastern United States. The disease is caused by the interaction of the aggressive bark beetle Pityophthorus juglandis Blackman and the canker-forming fungus, Geosmithia morbida M. Kolarik, E. Freeland, C. Utley & Tisserat, carried by the beetle. Other insects also colonize TCD-symptomatic trees and may also carry pathogens. A trap tree survey was conducted in Indiana and Missouri to characterize the assemblage of ambrosia beetles, bark beetles, and other weevils attracted to the main stems and crowns of stressed black walnut. More than 100 trees were girdled and treated with glyphosate (Riverdale Razor Pro, Burr Ridge, Illinois) at 27 locations. Nearly 17,000 insects were collected from logs harvested from girdled walnut trees. These insects represented 15 ambrosia beetle, four bark beetle, and seven other weevil species. The most abundant species included Xyleborinus saxeseni Ratzburg, Xylosandrus crassiusculus Motschulsky, Xylosandrus germanus Blandford, Xyleborus affinis Eichhoff, and Stenomimus pallidus Boheman. These species differed in their association with the stems or crowns of stressed trees. Multiple species of insects were collected from individual trees and likely colonized tissues near each other. At least three of the abundant species found (S. pallidus, X. crassiusculus, and X. germanus) are known to carry propagules of canker-causing fungi of black walnut. In summary, a large number of ambrosia beetles, bark beetles, and other weevils are attracted to stressed walnut trees in Indiana and Missouri. Several of these species have the potential to introduce walnut canker pathogens during colonization.

  5. Bark-beetle infestation affects water quality in the Rocky Mountains of Colorado

    NASA Astrophysics Data System (ADS)

    Mikkelson, K.; Dickenson, E.; Maxwell, R. M.; McCray, J. E.; Sharp, J. O.

    2012-12-01

    In the previous decade, millions of acres in the Rocky Mountains of Colorado have been infested by the mountain pine beetle (MPB) leading to large-scale tree mortality. These vegetation changes can impact hydrological and biogeochemical processes, possibly altering the leaching of natural organic matter to surrounding waters and increasing the potential for harmful disinfection byproducts (DBP) during water treatments. To investigate these adverse outcomes, we have collected water quality data sets from local water treatment facilities in the Rocky Mountains of Colorado that have either been infested with MPB or remain a control. Results demonstrate significantly more total organic carbon (TOC) and DBPs in water treatment facilities receiving their source water from infested watersheds as compared to the control sites. Temporal DBP concentrations in MPB-watersheds also have increased significantly in conjunction with the bark-beetle infestation. Interestingly, only modest increases in TOC concentrations were observed in infested watersheds despite more pronounced increases in DBP concentrations. Total trihalomethanes, a heavily regulated DBP, was found to approach the regulatory limit in two out of four reporting quarters at facilities receiving their water from infested forests. These findings indicate that bark-beetle infestation alters TOC composition and loading in impacted watersheds and that this large-scale phenomenon has implications on the municipal water supply in the region.

  6. Spatial and Temporal Patterns of Observed Bark Beetle-Caused Tree Mortality in Western United States and British Columbia

    NASA Astrophysics Data System (ADS)

    Meddens, A. J.; Hicke, J. A.; Ferguson, C. A.

    2011-12-01

    Outbreaks of aggressive bark beetle species cause widespread tree mortality, affecting wildlife habitat, wildfire risk, forest recovery, biogeochemical cycling, and biophysical processes. As a result, agencies responsible for forest management in the US and British Columbia are concerned about monitoring outbreaks and so conduct aerial surveys to map these forest disturbances. Here, we describe a gridded product of bark beetle disturbances for the western conterminous United States (1997-2009) and British Columbia (2001-2009). We converted aerial survey polygon data into 1-km2 grids for each combination of host type (e.g., lodgepole pine) and bark beetle species (e.g., mountain pine beetle) available in the US, and for each bark beetle species available in British Columbia. Polygon data are considered "affected area" because the polygons include live and killed trees. We converted affected area to mortality area within each grid cell for each year. We compared the number of killed trees from the US data set with high-resolution classified imagery in Idaho, Colorado, and New Mexico, finding that the number of trees reported by the aerial surveys in these locations was substantially underestimated. We adjusted mortality area for the US and found better matches with the spatial patterns and severity of the British Columbia mortality area. As a result, we produced US grids for lower (from the original aerial survey) and upper (with adjustment) estimates. Bark beetle mortality occurred across the entire study domain and temporal and spatial patterns differed among bark beetle species. The calculated mortality area from all bark beetles combined was 0.42 million ha for the lower estimate and 5.04 million ha for the upper estimate in the western conterminous US from 1997 to 2009, and 5.07 million ha in British Columbia from 2001 to 2009. The analyses suggest that mortality area caused by bark beetles in the western conterminous US exceeded the British Columbia mortality

  7. The biophysical controls on tree defense against attacking bark beetles in managed pine forests of the Southeastern United States

    NASA Astrophysics Data System (ADS)

    Novick, K. A.; Miniat, C. F.; Denham, S. O.; Ritger, H. M.; Williams, C.; Guldin, J. M.; Bragg, D.; Coyle, D.

    2013-12-01

    Bark beetles are highly damaging pests capable of destroying large areas of southern pine forests, with significant consequences for regional timber supply and forest ecosystem carbon dynamics. A number of recent studies have shown that following bark beetle outbreak, significant effects on ecosystem carbon and water cycling can occur. Relatively few studies have explored how ecosystem carbon and water cycling interact with other factors to control the hazard or risk of bark beetle outbreaks; these interactions, and their representation in conceptual model frameworks, are the focus of this study. Pine trees defend against bark beetle attacks through the exudation of of resin - a viscous compound that deters attacking beetles through a combination of chemical and physical mechanisms. Constitutive resin flow (CRF, representing resin produced before attack) is assumed to be directly proportional to the balance between gross primary productivity (GPP) and net primary productivity (NPP) according to the Growth-Differentiation Balance theory (GDB). Thus, predictions for tree mortality and bark beetle dynamics under different management and climate regimes may be more accurate if a model framework describing the biophysical controls on resin production (e.g., GDB) were employed. Here, we synthesize measurements of resin flow, bark beetle dynamics, and ecosystem C flux from three managed loblolly pine forests in the Southeastern U.S.: the Duke Forest in Durham, NC; the Savannah River DOE site near Aiken, SC; and the Crossett Experimental Forest in southern Arkansas. We also explore the relationship between CRF and induced resin flow (IRF, representing the de novo synthesis of resin following stem wounding) in the latter two sites, where IRF was promoted by a novel tree baiting approach and prescribed fire, respectively. We assimilate observations within a hierarchical Bayesian framework to 1) test whether observations conform to the GDB hypothesis, and 2) explore effects

  8. Delayed conifer mortality after fuel reduction treatments: interactive effects of fuel, fire intensity, and bark beetles.

    PubMed

    Youngblood, Andrew; Grace, James B; McIver, James D

    2009-03-01

    Many low-elevation dry forests of the western United States contain more small trees and fewer large trees, more down woody debris, and less diverse and vigorous understory plant communities compared to conditions under historical fire regimes. These altered structural conditions may contribute to increased probability of unnaturally severe wildfires, susceptibility to uncharacteristic insect outbreaks, and drought-related mortality. Broad-scale fuel reduction and restoration treatments are proposed to promote stand development on trajectories toward more sustainable structures. Little research to date, however, has quantified the effects of these treatments on the ecosystem, especially delayed and latent tree mortality resulting directly or indirectly from treatments. In this paper, we explore complex hypotheses relating to the cascade of effects that influence ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) mortality using structural equation modeling (SEM). We used annual census and plot data through six growing seasons after thinning and four growing seasons after burning from a replicated, operational-scale, completely randomized experiment conducted in northeastern Oregon, USA, as part of the national Fire and Fire Surrogate study. Treatments included thin, burn, thin followed by burn (thin + burn), and control. Burn and thin + burn treatments increased the proportion of dead trees while the proportion of dead trees declined or remained constant in thin and control units, although the density of dead trees was essentially unchanged with treatment. Most of the new mortality (96%) occurred within two years of treatment and was attributed to bark beetles. Bark beetle-caused tree mortality, while low overall, was greatest in thin + burn treatments. SEM results indicate that the probability of mortality of large-diameter ponderosa pine from bark beetles and wood borers was directly related to surface fire severity and bole charring, which

  9. Bark beetle-induced tree mortality alters stand energy budgets due to water budget changes

    NASA Astrophysics Data System (ADS)

    Reed, David E.; Ewers, Brent E.; Pendall, Elise; Frank, John; Kelly, Robert

    2016-10-01

    Insect outbreaks are major disturbances that affect a land area similar to that of forest fires across North America. The recent mountain pine bark beetle (D endroctonus ponderosae) outbreak and its associated blue stain fungi (Grosmannia clavigera) are impacting water partitioning processes of forests in the Rocky Mountain region as the spatially heterogeneous disturbance spreads across the landscape. Water cycling may dramatically change due to increasing spatial heterogeneity from uneven mortality. Water and energy storage within trees and soils may also decrease, due to hydraulic failure and mortality caused by blue stain fungi followed by shifts in the water budget. This forest disturbance was unique in comparison to fire or timber harvesting because water fluxes were altered before significant structural change occurred to the canopy. We investigated the impacts of bark beetles on lodgepole pine (Pinus contorta) stand and ecosystem level hydrologic processes and the resulting vertical and horizontal spatial variability in energy storage. Bark beetle-impacted stands had on average 57 % higher soil moisture, 1.5 °C higher soil temperature, and 0.8 °C higher tree bole temperature over four growing seasons compared to unimpacted stands. Seasonal latent heat flux was highly correlated with soil moisture. Thus, high mortality levels led to an increase in ecosystem level Bowen ratio as sensible heat fluxes increased yearly and latent heat fluxes varied with soil moisture levels. Decline in canopy biomass (leaf, stem, and branch) was not seen, but ground-to-atmosphere longwave radiation flux increased, as the ground surface was a larger component of the longwave radiation. Variability in soil, latent, and sensible heat flux and radiation measurements increased during the disturbance. Accounting for stand level variability in water and energy fluxes will provide a method to quantify potential drivers of ecosystem processes and services as well as lead to greater

  10. Towards scaling interannual ecohydrological responses of conifer forests to bark beetle infestations from individuals to landscapes

    NASA Astrophysics Data System (ADS)

    Mackay, D. S.; Ewers, B. E.; Peckham, S. D.; Savoy, P.; Reed, D. E.; Frank, J. M.

    2013-12-01

    Widespread epidemics of forest-damaging insects have severe implications for the interconnections between water and ecosystem processes under present-day climate. How these systems respond to future climates is highly uncertain, and so there is a need for a better understanding of the effects of such disturbances on plant hydraulics, and the consequent effects on ecosystem processes. Moreover, large-scale manifestations of such disturbances require scaling knowledge obtained from individual trees or stands up to a regional extent. This requires a conceptual framework that integrates physical and biological processes that are immutable and scalable. Indeed, in Western North America multiple conifer species have been impacted by the bark beetle epidemic, but the prediction of such widespread outbreaks under changing environmental conditions must be generalized from a relatively small number of ground-based observations. Using model-data fusion we examine the fundamental principles that drive ecological and hydrological responses to bark beetles infestation from individuals to regions. The study includes a mid-elevation (2750 m a.s.l) lodgepole pine forest and higher (3190 m a.s.l.) elevation Engelmann spruce - fir forest in southern Wyoming. The study included a suite of observations, comprising leaf gas exchange, non-structural carbon (NSC), plant hydraulics, including sap flux transpiration (E), vulnerability to cavitation, leaf water potentials, and eddy covariance, were made pre-, during-, and post-disturbance, as the bark beetle infestation moved through these areas. Numerous observations tested hypotheses generated by the Terrestrial Regional Ecosystem Exchange Simulator (TREES), which integrates soil hydraulics and dynamic tree hydraulics (cavitation) with canopy energy and gas exchange, and operates at scales from individuals to landscapes. TREES accurately predicted E and NSC dynamics among individuals spanning pre- and post-disturbance periods, with the 95

  11. Mapping and detecting bark beetle-caused tree mortality in the western United States

    NASA Astrophysics Data System (ADS)

    Meddens, Arjan J. H.

    Recently, insect outbreaks across North America have dramatically increased and the forest area affected by bark beetles is similar to that affected by fire. Remote sensing offers the potential to detect insect outbreaks with high accuracy. Chapter one involved detection of insect-caused tree mortality on the tree level for a 90km2 area in northcentral Colorado. Classes of interest included green trees, multiple stages of post-insect attack tree mortality including dead trees with red needles ("red-attack") and dead trees without needles ("gray-attack"), and non-forest. The results illustrated that classification of an image with a spatial resolution similar to the area of a tree crown outperformed that from finer and coarser resolution imagery for mapping tree mortality and non-forest classes. I also demonstrated that multispectral imagery could be used to separate multiple postoutbreak attack stages (i.e., red-attack and gray-attack) from other classes in the image. In Chapter 2, I compared and improved methods for detecting bark beetle-caused tree mortality using medium-resolution satellite data. I found that overall classification accuracy was similar between single-date and multi-date classification methods. I developed regression models to predict percent red attack within a 30-m grid cell and these models explained >75% of the variance using three Landsat spectral explanatory variables. Results of the final product showed that approximately 24% of the forest within the Landsat scene was comprised of tree mortality caused by bark beetles. In Chapter 3, I developed a gridded data set with 1-km2 resolution using aerial survey data and improved estimates of tree mortality across the western US and British Columbia. In the US, I also produced an upper estimate by forcing the mortality area to match that from high-resolution imagery in Idaho, Colorado, and New Mexico. Cumulative mortality area from all bark beetles was 5.46 Mha in British Columbia in 2001-2010 and

  12. Effects of bark beetle outbreaks and wildfire in the western US on carbon stocks during recent decades

    NASA Astrophysics Data System (ADS)

    Hicke, J. A.; Meddens, A. J.; Allen, C. D.

    2012-12-01

    Bark beetle outbreaks and wildfires are significant forest disturbances that respond strongly to climate and affect future climate through carbon cycling. Extensive tree mortality has occurred in western North America as a result of these disturbances. Here we present an analysis that quantifies impacts of these two disturbances to tree carbon stocks. Mortality area from bark beetles was derived from aerial surveys in 1997-2010 in the western US and 2001-2010 in British Columbia that were converted to mortality area by multiplying by species-specific crown areas and, in the case of the US, adjusted for underestimation. We summed moderate- and high-severity burned areas in forests from the Monitoring Trends in Burn Severity (MTBS) database from 1984-2009 to estimate mortality area from forest fires. Mortality area was then combined with spatially explicit maps of carbon stocks to estimate the amount of carbon in killed trees. Notable findings include that the mortality area from bark beetle outbreaks in the western US was comparable to the mortality area in British Columbia during the last few decades. In the western US, mortality area from bark beetles was similar to or exceeded that from forest fires. Carbon stocks in trees killed by these two disturbance types (beetles and fire) had similar spatial and temporal patterns as tree mortality, illustrating the importance of each of these disturbances in governing regional forest carbon fluxes.

  13. Evolutionary assembly of the conifer fauna: distinguishing ancient from recent associations in bark beetles.

    PubMed

    Sequeira, A S; Normark, B B; Farrell, B D

    2000-12-07

    Several shifts from ancestral conifer feeding to angiosperm feeding have been implicated in the unparalleled diversification of beetle species. The single largest angiosperm-feeding beetle clade occurs in the weevils, and comprises the family Curculionidae and relatives. Most authorities confidently place the bark beetles (Scolytidae) within this radiation of angiosperm feeders. However, some clues indicate that the association between conifers and some scolytids, particularly in the tribe Tomicini, is a very ancient one. For instance, several fragments of Gondwanaland (South America, New Caledonia, Australia and New Guinea) harbour endemic Tomicini specialized on members of the formerly widespread and abundant conifer family Araucariaceae. As a first step towards resolving this seeming paradox, we present a phylogenetic analysis of the beetle family Scolytidae with particularly intensive sampling of conifer-feeding Tomicini and allies. We sequenced and analysed elongation factor 1alpha and nuclear rDNAs 18S and 28S for 45 taxa, using members of the weevil family Cossoninae as an out-group. Our results indicate that conifer feeding is the ancestral host association of scolytids, and that the most basal lineages of scolytids feed on Aramucaria. If scolytids are indeed nested within a great angiosperm-feeding clade, as many authorities have held, then a reversion to conifer feeding in ancestral scolytids appears to have occurred in the Mesozoic, when Araucaria still formed a major component of the woody flora.

  14. High individual variation in pheromone production by tree-killing bark beetles (Coleoptera: Curculionidae: Scolytinae)

    NASA Astrophysics Data System (ADS)

    Pureswaran, Deepa S.; Sullivan, Brian T.; Ayres, Matthew P.

    2008-01-01

    Aggregation via pheromone signalling is essential for tree-killing bark beetles to overcome tree defenses and reproduce within hosts. Pheromone production is a trait that is linked to fitness, so high individual variation is paradoxical. One explanation is that the technique of measuring static pheromone pools overestimates true variation among individuals. An alternative hypothesis is that aggregation behaviour dilutes the contribution of individuals to the trait under selection and reduces the efficacy of natural selection on pheromone production by individuals. We compared pheromone measurements from traditional hindgut extractions of female southern pine beetles with those obtained by aerating individuals till they died. Aerations showed greater total pheromone production than hindgut extractions, but coefficients of variation (CV) remained high (60-182%) regardless of collection technique. This leaves the puzzle of high variation unresolved. A novel but simple explanation emerges from considering bark beetle aggregation behaviour. The phenotype visible to natural selection is the collective pheromone plume from hundreds of colonisers. The influence of a single beetle on this plume is enhanced by high variation among individuals but constrained by large group sizes. We estimated the average contribution of an individual to the pheromone plume across a range of aggregation sizes and showed that large aggregation sizes typical in mass attacks limit the potential of natural selection because each individual has so little effect on the overall plume. Genetic variation in pheromone production could accumulate via mutation and recombination, despite strong effects of the pheromone plume on the fitness of individuals within the aggregation. Thus, aggregation behaviour, by limiting the efficacy of natural selection, can allow the persistence of extreme phenotypes in nature.

  15. High individual variation in pheromone production by tree-killing bark beetles (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Pureswaran, Deepa S; Sullivan, Brian T; Ayres, Matthew P

    2008-01-01

    Aggregation via pheromone signalling is essential for tree-killing bark beetles to overcome tree defenses and reproduce within hosts. Pheromone production is a trait that is linked to fitness, so high individual variation is paradoxical. One explanation is that the technique of measuring static pheromone pools overestimates true variation among individuals. An alternative hypothesis is that aggregation behaviour dilutes the contribution of individuals to the trait under selection and reduces the efficacy of natural selection on pheromone production by individuals. We compared pheromone measurements from traditional hindgut extractions of female southern pine beetles with those obtained by aerating individuals till they died. Aerations showed greater total pheromone production than hindgut extractions, but coefficients of variation (CV) remained high (60-182%) regardless of collection technique. This leaves the puzzle of high variation unresolved. A novel but simple explanation emerges from considering bark beetle aggregation behaviour. The phenotype visible to natural selection is the collective pheromone plume from hundreds of colonisers. The influence of a single beetle on this plume is enhanced by high variation among individuals but constrained by large group sizes. We estimated the average contribution of an individual to the pheromone plume across a range of aggregation sizes and showed that large aggregation sizes typical in mass attacks limit the potential of natural selection because each individual has so little effect on the overall plume. Genetic variation in pheromone production could accumulate via mutation and recombination, despite strong effects of the pheromone plume on the fitness of individuals within the aggregation. Thus, aggregation behaviour, by limiting the efficacy of natural selection, can allow the persistence of extreme phenotypes in nature.

  16. Bark Beetle-Induced Mortality Impacts on Forest Biogeochemical Cycles are Less than Expected

    NASA Astrophysics Data System (ADS)

    Ewers, B. E.; Pendall, E.; Norton, U.; Millar, D.; Mackay, D. S.; Frank, J. M.; Massman, W. J.; Hyde, K.

    2015-12-01

    Bark beetles increased conifer tree mortality across western North America due to past land use interacting with climate change. For both mountain pine and spruce beetles, the mechanism of mortality is hydraulic failure due to xylem occlusion by beetle-carried blue stain fungi, which causes the trees to die from symptoms that are the same as extreme drought. As the mortality event peaked in the last decade, the hypothesized effects on forest biogeochemical processes were 1) lower forest water use from xylem occlusion, 2) less carbon uptake from limited canopy gas exchange, 3) increased nitrogen cycling from increased litterfall and soil moisture and 4) increased streamflow and organic N and C loading at the watershed scale from the first three consequences. The stand-scale effects during mortality were as predicted with transpiration falling by 10-35% in proportion to the occluded xylem, carbon uptake declining by > 50% due to lack of canopy gas exchange and nitrogen cycling increasing from elevated litter inputs and stimulated organic matter decomposition. Some stands, especially mid-elevation lodgepole pine, did not follow these trends because of residual vegetation taking advantage of the increased resources from the dead trees and rapid succession within 5 years of new grasses, shrubs and tree seedlings as well as increased resource use by surviving canopy trees. In a high elevation spruce stand, the lower water use lasted for only three years while summer carbon uptake was only significantly reduced for a year. At the scale of small to medium-sized watersheds, the impact of mortality was not detectable in stream flow due to the spatial and temporal scale muting of the mortality signal as temporal and spatial scales increase. Current ecosystem and watershed models miss these compensating mechanisms with increasing scale and thus over predict the impact of bark beetle mortality.

  17. 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.

  18. Two newly introduced tropical bark and ambrosia beetles (Coleoptera: Curculionidae, Scolytinae) damaging figs (Ficus carica) in southern Italy.

    PubMed

    Faccoli, Massimo; Campo, Giuseppe; Perrotta, Giancarlo; Rassati, Davide

    2016-07-14

    In summer 2014, the bark beetle Hypocryphalus scabricollis (Eichhoff) and the ambrosia beetle Xyleborus bispinatus Eichhoff, species new to Italy and Europe, respectively, were found for the first time in south-eastern Sicily (Italy). Large infestations of the two species were recorded in many plantations of common fig (Ficus carica L.) both in 2014 and 2015. Data concerning insect characteristics, taxonomy, and distribution are briefly reported.

  19. Flavan-3-ols in Norway Spruce: Biosynthesis, Accumulation, and Function in Response to Attack by the Bark Beetle-Associated Fungus Ceratocystis polonica1[C][W][OPEN

    PubMed Central

    Hammerbacher, Almuth; Paetz, Christian; Wright, Louwrance P.; Fischer, Thilo C.; Bohlmann, Joerg; Davis, Andrew J.; Fenning, Trevor M.; Gershenzon, Jonathan; Schmidt, Axel

    2014-01-01

    Proanthocyanidins (PAs) are common polyphenolic polymers of plants found in foliage, fruit, bark, roots, rhizomes, and seed coats that consist of flavan-3-ol units such as 2,3-trans-(+)-catechin and 2,3-cis-(–)-epicatechin. Although the biosynthesis of flavan-3-ols has been studied in angiosperms, little is known about their biosynthesis and ecological roles in gymnosperms. In this study, the genes encoding leucoanthocyanidin reductase, a branch point enzyme involved in the biosynthesis of 2,3-trans-(+)-flavan-3-ols, were identified and functionally characterized in Norway spruce (Picea abies), the most widespread and economically important conifer in Europe. In addition, the accumulation of flavan-3-ols and PAs was investigated in Norway spruce saplings after wounding or inoculation with the fungal pathogen Ceratocystis polonica, which is vectored by bark beetles (Ips typographus) and is usually present during fatal beetle attacks. Monomeric and dimeric flavan-3-ols were analyzed by reverse-phase high-pressure liquid chromatography, while the size and subunit composition of larger PAs were characterized using a novel acid hydrolysis method and normal phase chromatography. Only flavan-3-ol monomers with 2,3-trans stereochemistry were detected in spruce bark; dimeric and larger PAs contained flavan-3-ols with both 2,3-trans and 2,3-cis stereochemistry. Levels of monomers as well as PAs with a higher degree of polymerization increased dramatically in spruce bark after infection by C. polonica. In accordance with their role in the biosynthesis of 2,3-trans-(+)-flavan-3-ols, transcript abundance of Norway spruce LEUCOANTHOCYANIDIN REDUCTASE genes also increased significantly during fungal infection. Bioassays with C. polonica revealed that the levels of 2,3-trans-(+)-catechin and PAs that are produced in the tree in response to fungal infection inhibit C. polonica growth and can therefore be considered chemical defense compounds. PMID:24550241

  20. Flavan-3-ols in Norway spruce: biosynthesis, accumulation, and function in response to attack by the bark beetle-associated fungus Ceratocystis polonica.

    PubMed

    Hammerbacher, Almuth; Paetz, Christian; Wright, Louwrance P; Fischer, Thilo C; Bohlmann, Joerg; Davis, Andrew J; Fenning, Trevor M; Gershenzon, Jonathan; Schmidt, Axel

    2014-04-01

    Proanthocyanidins (PAs) are common polyphenolic polymers of plants found in foliage, fruit, bark, roots, rhizomes, and seed coats that consist of flavan-3-ol units such as 2,3-trans-(+)-catechin and 2,3-cis-(-)-epicatechin. Although the biosynthesis of flavan-3-ols has been studied in angiosperms, little is known about their biosynthesis and ecological roles in gymnosperms. In this study, the genes encoding leucoanthocyanidin reductase, a branch point enzyme involved in the biosynthesis of 2,3-trans-(+)-flavan-3-ols, were identified and functionally characterized in Norway spruce (Picea abies), the most widespread and economically important conifer in Europe. In addition, the accumulation of flavan-3-ols and PAs was investigated in Norway spruce saplings after wounding or inoculation with the fungal pathogen Ceratocystis polonica, which is vectored by bark beetles (Ips typographus) and is usually present during fatal beetle attacks. Monomeric and dimeric flavan-3-ols were analyzed by reverse-phase high-pressure liquid chromatography, while the size and subunit composition of larger PAs were characterized using a novel acid hydrolysis method and normal phase chromatography. Only flavan-3-ol monomers with 2,3-trans stereochemistry were detected in spruce bark; dimeric and larger PAs contained flavan-3-ols with both 2,3-trans and 2,3-cis stereochemistry. Levels of monomers as well as PAs with a higher degree of polymerization increased dramatically in spruce bark after infection by C. polonica. In accordance with their role in the biosynthesis of 2,3-trans-(+)-flavan-3-ols, transcript abundance of Norway spruce LEUCOANTHOCYANIDIN REDUCTASE genes also increased significantly during fungal infection. Bioassays with C. polonica revealed that the levels of 2,3-trans-(+)-catechin and PAs that are produced in the tree in response to fungal infection inhibit C. polonica growth and can therefore be considered chemical defense compounds.

  1. Responses of the Mediterranean pine shoot beetle Tomicus destruens (Wollaston) to pine shoot and bark volatiles.

    PubMed

    Faccoli, Massimo; Anfora, Gianfranco; Tasin, Marco

    2008-09-01

    The pine shoot beetle Tomicus destruens has two dispersal phases per generation. In the first, mature adults move toward trunks of dying pines to lay eggs; in the second, callow adults move toward the shoots of healthy pines for maturation feeding. However, there is no information on the chemical stimuli that govern host selection by T. destruens adults. The aims of this study were: (1) to identify the volatiles released by shoots and bark of stone pine that are behaviorally and electrophysiologically active on T. destruens; (2) to verify which blends and concentrations of such volatiles are differently active on males and females, as well as on callow and mature adults, during the two host search phases (breeding and feeding). A four-arm olfactometer was used to test the behavior of walking T. destruens adults toward various sources of volatiles including fresh shoots and bark, their collected volatiles, and two synthetic blends. For each odor, the behavior of both callow and mature males and females was recorded individually. Shoot and bark extracts were analyzed by coupled gas chromatography and mass spectrometry (GC-MS), and tested by gas chromatography coupled with electroantennography (GC-EAD) on T. destruens males and females. Two blends of two (alpha-pinene and beta-myrcene; blend A) and three (alpha-pinene, beta- myrcene, and alpha-terpinolene; blend B) synthetic compounds, chosen among those that induce EAD responses and known to be attractive for other bark beetle species, were tested in the olfactometer at five concentrations. Insect behavior was affected by the degree of sexual maturation but not by sex. Callow insects were attracted by shoots and their extracts, while mature individuals by bark and its extracts. Six extracted compounds were active on T. destruens antennae: limonene, (Z)-3-hexen-1-ol and beta-caryophyllene, alpha-pinene, beta-myrcene, and alpha-terpinolene. alpha-Terpinolene, released only by bark, was active only on mature insects

  2. Surface energy flux consequences of bark beetle outbreaks in the south-central Rockies using MODIS data

    NASA Astrophysics Data System (ADS)

    Vanderhoof, M. K.; Williams, C. A.

    2012-12-01

    Changes in canopy cover due to disturbance-related mortality have been shown to profoundly impact parameters within the surface energy balance and water budget. A shift in such fluxes can have consequences for surface temperature, cloudiness, run-off and stream flow, forest regeneration and net primary productivity. Current outbreaks of native bark beetles in western North America are some of the largest and most severe in recorded history. In recent outbreaks, bark beetles have reduced the basal area of host-dominated forests by up to 70%; with over-story mortality often exceeding 90% in mature, even-aged stands. The magnitude, frequency and intensity of recent outbreaks have been attributed to warmer summer and winter temperatures and drought conditions as a result of climate change. However, despite the likelihood that canopy mortality from bark beetle attacks will have profound effects on forest albedo and evapotranspiration, consequences for this disturbance type remain largely un-documented. This study addressed the question: how does a bark beetle outbreak event influence surface albedo and evapotranspiration? Seasonal patterns of surface temperature, albedo, evapotranspiration, and radiative forcing were modeled for lodgepole and ponderosa pine stands by outbreak age using Moderate Resolution Imaging Spectroradiometer (MODIS) data within the south-central Rocky Mountains. Beetle damage data was derived from both field-based plots as well as aerial surveys. The prevalence of bark beetle outbreaks in high-elevation environments, which are exceedingly sensitive to climate change, necessitates the importance of understanding the energy and evapotranspiration consequences of such events.

  3. 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.

  4. Monoterpene Variation Mediated Attack Preference Evolution of the Bark Beetle Dendroctonus valens

    PubMed Central

    Liu, Zhudong; Wang, Bo; Xu, Bingbing; Sun, Jianghua

    2011-01-01

    Several studies suggest that some bark beetle like to attack large trees. The invasive red turpentine beetle (RTB), Dendroctonus valens LeConte, one of the most destructive forest pests in China, is known to exhibit this behavior. Our previous study demonstrated that RTBs preferred to attack large-diameter trees (diameter at breast height, DBH ≥30 cm) over small-diameter trees (DBH ≤10 cm) in the field. In the current study, we studied the attacking behavior and the underlying mechanisms in the laboratory. Behavioral assays showed that RTBs preferred the bark of large-DBH trees and had a higher attack rate on the bolts of these trees. Y-tube assays showed that RTBs preferred the volatiles released by large-DBH trees to those released by small-DBH trees. Subsequent analysis revealed that both large- and small-DBH trees had the same composition of monoterpenes, but the concentration of each component differed; thus it appeared that the concentrations acted as cues for RTBs to locate the right-sized host which was confirmed by further behavioral assays. Moreover, large-DBH pine trees provided more spacious habitat and contained more nutrients, such as nitrogen, than did small-DBH pine trees, which benefited RTBs' fecundity and larval development. RTBs seem to have evolved mechanisms to locate those large hosts that will allow them to maximize their fitness. Monoterpene variation mediated attack preference implies the potential for the management of RTB. PMID:21811555

  5. Changes in metal mobility associated with bark beetle-induced tree mortality.

    PubMed

    Mikkelson, Kristin M; Bearup, Lindsay A; Navarre-Sitchler, Alexis K; McCray, John E; Sharp, Jonathan O

    2014-05-01

    Recent large-scale beetle infestations have caused extensive mortality to conifer forests resulting in alterations to dissolved organic carbon (DOC) cycling, which in turn can impact metal mobility through complexation. This study analyzed soil-water samples beneath impacted trees in concert with laboratory flow-through soil column experiments to explore possible impacts of the bark beetle infestation on metal release and transport. The columns mimicked field conditions by introducing pine needle leachate and artificial rainwater through duplicate homogenized soil columns and measuring effluent metal (focusing on Al, Cu, and Zn) and DOC concentrations. All three metals were consistently found in higher concentrations in the effluent of columns receiving pine needle leachate. In both the field and laboratory, aluminum mobility was largely correlated with the hydrophobic fraction of the DOC, while copper had the largest correlation with total DOC concentrations. Geochemical speciation modeling supported the presence of DOC-metal complexes in column experiments. Copper soil water concentrations in field samples supported laboratory column results, as they were almost twice as high under grey phase trees than under red phase trees further signifying the importance of needle drop. Pine needle leachate contained high concentrations of Zn (0.1 mg l(-1)), which led to high effluent zinc concentrations and sorption of zinc to the soil matrix representing a future potential source for release. In support, field soil-water samples underneath beetle-impacted trees where the needles had recently fallen contained approximately 50% more zinc as samples from under beetle-impacted trees that still held their needles. The high concentrations of carbon in the pine needle leachate also led to increased sorption in the soil matrix creating the potential for subsequent carbon release. While unclear if manifested in adjacent surface waters, these results demonstrate an increased

  6. Bark Beetle Impacts on Ecosystem Processes are Over Quickly and Muted Spatially

    NASA Astrophysics Data System (ADS)

    Ewers, B. E.; Norton, U.; Borkhuu, B.; Reed, D. E.; Peckham, S. D.; Biederman, J. A.; King, A.; Gochis, D. J.; Brooks, P. D.; Harpold, A. A.; Frank, J. M.; Massman, W. J.; Mackay, D. S.; Pendall, E. G.

    2013-12-01

    The recent epidemic of bark beetles across western North America has impacted conifers from low to high elevations from New Mexico to Yukon. The mechanism of mortality is clear, with both mountain pine and spruce beetles killing trees by introducing xylem occluding blue stain fungi which dramatically stops transpiration. The visual impact of this outbreak is stunning, with mortality of canopy trees over 90% in some stands. However, emerging work shows that the impact on ecosystem processes is not as dramatic. We hypothesize that increased soil water and nitrogen sets up rapid succession of plant communities, which quickly restores ecosystem processing of water, carbon and nitrogen, while spatial patchiness of mortality and belowground responses mutes the impact as spatial scale increases from stands to watersheds. In support of our hypothesis we found 1) Soil nitrogen and moisture increase within one growing season but decrease to the same as uninfested stands five years later. 2) Soil respiration is correlated with live tree basal area suggesting a large component of autotrophic respiration. 3) Once stands have more than 50% basal area mortality, seedling density increases up to five fold and total non-tree understory cover increased two fold both within five years after infestation. 4) Ecosystem scale estimates of water vapor fluxes do not decline as rapidly as overstory leaf area. 5) Stable isotopes of snow, soil and stream water suggest that increased below canopy evapotranspiration nearly compensates for reduced canopy transpiration. 6) Nested watershed data shows that precipitation variations are much more important in regulating streamflow than changes in canopies from bark beetle induced mortality. These results were tested in the Terrestrial Regional Ecosystem Exchange Simulator (TREES) model. TREES was able to predict annual changes in the carbon fluxes but had difficulty simulating soil moisture and annual water budgets likely due to inadequate abiotic

  7. Do novel genotypes drive the success of an invasive bark beetle-fungus complex? Implications for potential reinvasion.

    PubMed

    Lu, Min; Wingfield, Michael J; Gillette, Nancy; Sun, Jiang-Hua

    2011-11-01

    Novel genotypes often arise during biological invasions, but their role in invasion success has rarely been elucidated. Here we examined the population genetics and behavior of the fungus, Leptographium procerum, vectored by a highly invasive bark beetle, Dendroctonus valens, to determine whether genetic changes in the fungus contributed to the invasive success of the beetle-fungal complex in China. The fungus was introduced by the beetle from the United States to China, where we identified several novel genotypes using microsatellite markers. These novel genotypes were more pathogenic to Chinese host seedlings than were other genotypes and they also induced the release of higher amounts of 3-carene, the primary host attractant for the beetle vector, from inoculated seedlings. This evidence suggests a possible mechanism, based on the evolution of a novel genotype during the two or three decades since its introduction, for the success of the beetle-fungal complex in its introduced region.

  8. Predation by Flat Bark Beetles (Coleoptera: Silvanidae and Laemophloeidae) on Coffee Berry Borer (Coleoptera: Curculionidae) in Hawaii coffee

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coffee berry borer(CBB), Hypothenemus hampei, is a serious pest of coffee worldwide and a new invasive pest in Hawaii. Adult flat bark beetles, mainly Leptophloeus sp.(75%) and Cathartus quadricollis(21%) (Coleoptera: Laemophloeidae and Silvanidae, respectively), were found feeding in CBB-infested c...

  9. A population genetic model of evolution of host-mate attraction and nonhost repulsion in a bark beetle Pityogenes bidentatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Studies have shown that the bark beetle Pityogenes bidentatus (Coleoptera, Curculionidae, Scolytinae) avoids volatiles of nonhost trees (Norway spruce, birch, and oak) and healthy host Scotch pine when orienting to aggregation pheromone. A population genetic model of two behavioral genes was hypothe...

  10. Bark beetles, pityogenes bidentatus, orienting to aggregation pheromone avoid conifer monoterpene odors when flying but not when walking

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous studies have provided evidence that monoterpene odors from healthy host Scotch pine (Pinus sylvestris) and non-host Norway spruce (Picea abies) significantly reduce the attraction of flying bark beetles, Pityogenes bidentatus, to their aggregation pheromone components (grandisol and cis-ver...

  11. Do mites phoretic on elm bark beetles contribute to the transmission of Dutch elm disease?

    PubMed

    Moser, John C; Konrad, Heino; Blomquist, Stacy R; Kirisits, Thomas

    2010-02-01

    Dutch elm disease (DED) is a destructive vascular wilt disease of elm (Ulmus) trees caused by the introduced Ascomycete fungus Ophiostoma novo-ulmi. In Europe, this DED pathogen is transmitted by elm bark beetles in the genus Scolytus. These insects carry phoretic mites to new, suitable habitats. The aim of this study was to record and quantify conidia and ascospores of O. novo-ulmi on phoretic mites on the three elm bark beetle species Scolytus multistriatus, Scolytus pygmaeus, and Scolytus scolytus. Spores of O. novo-ulmi were found on four of the ten mite species phoretic on Scolytus spp. These included Elattoma fraxini, Proctolaelaps scolyti, Pseudotarsonemoides eccoptogasteri, and Tarsonemus crassus. All four species had spores attached externally to their body surfaces. However, T. crassus carried most spores within its sporothecae, two paired pocket-like structures adapted for fungal transmission. Individuals of Pr. scolyti also had O. novo-ulmi conidia and ascospores frequently in their digestive system, where they may remain viable. While E. fraxini and P. eccoptogasteri rarely had spores attached to their bodies, large portions of Pr. scolyti and T. crassus carried significant numbers of conidia and/or ascospores of O. novo-ulmi. P. scolyti and T. crassus, which likely are fungivores, may thus contribute to the transmission of O. novo-ulmi, by increasing the spore loads of individual Scolytus beetles during their maturation feeding on twigs of healthy elm trees, enhancing the chance for successful infection with the pathogen. Only S. scolytus, which is the most efficient vector of O. novo-ulmi in Europe, carried high numbers of Pr. scolyti and T. crassus, in contrast to S. multistriatus and S. pygmaeus, which are known as less efficient vectors. The high efficiency of S. scolytus in spreading Dutch elm disease may be partly due to its association with these two mites and the hyperphoretic spores of O. novo-ulmi they carry.

  12. Do mites phoretic on elm bark beetles contribute to the transmission of Dutch elm disease?

    NASA Astrophysics Data System (ADS)

    Moser, John C.; Konrad, Heino; Blomquist, Stacy R.; Kirisits, Thomas

    2010-02-01

    Dutch elm disease (DED) is a destructive vascular wilt disease of elm ( Ulmus) trees caused by the introduced Ascomycete fungus Ophiostoma novo-ulmi. In Europe, this DED pathogen is transmitted by elm bark beetles in the genus Scolytus. These insects carry phoretic mites to new, suitable habitats. The aim of this study was to record and quantify conidia and ascospores of O. novo-ulmi on phoretic mites on the three elm bark beetle species Scolytus multistriatus, Scolytus pygmaeus, and Scolytus scolytus. Spores of O. novo-ulmi were found on four of the ten mite species phoretic on Scolytus spp. These included Elattoma fraxini, Proctolaelaps scolyti, Pseudotarsonemoides eccoptogasteri, and Tarsonemus crassus. All four species had spores attached externally to their body surfaces. However, T. crassus carried most spores within its sporothecae, two paired pocket-like structures adapted for fungal transmission. Individuals of Pr. scolyti also had O. novo-ulmi conidia and ascospores frequently in their digestive system, where they may remain viable. While E. fraxini and P. eccoptogasteri rarely had spores attached to their bodies, large portions of Pr. scolyti and T. crassus carried significant numbers of conidia and/or ascospores of O. novo-ulmi. P. scolyti and T. crassus, which likely are fungivores, may thus contribute to the transmission of O. novo-ulmi, by increasing the spore loads of individual Scolytus beetles during their maturation feeding on twigs of healthy elm trees, enhancing the chance for successful infection with the pathogen. Only S. scolytus, which is the most efficient vector of O. novo-ulmi in Europe, carried high numbers of Pr. scolyti and T. crassus, in contrast to S. multistriatus and S. pygmaeus, which are known as less efficient vectors. The high efficiency of S. scolytus in spreading Dutch elm disease may be partly due to its association with these two mites and the hyperphoretic spores of O. novo-ulmi they carry.

  13. Riparian zones attenuate nitrogen loss following bark beetle-induced lodgepole pine mortality

    NASA Astrophysics Data System (ADS)

    Biederman, Joel A.; Meixner, Thomas; Harpold, Adrian A.; Reed, David E.; Gutmann, Ethan D.; Gaun, Janelle A.; Brooks, Paul D.

    2016-03-01

    A North American bark beetle infestation has killed billions of trees, increasing soil nitrogen and raising concern for N loss impacts on downstream ecosystems and water resources. There is surprisingly little evidence of stream N response in large basins, which may result from surviving vegetation uptake, gaseous loss, or dilution by streamflow from unimpacted stands. Observations are lacking along hydrologic flow paths connecting soils with streams, challenging our ability to determine where and how attenuation occurs. Here we quantified biogeochemical concentrations and fluxes at a lodgepole pine-dominated site where bark beetle infestation killed 50-60% of trees. We used nested observations along hydrologic flow paths connecting hillslope soils to streams of up to third order. We found soil water NO3 concentrations increased 100-fold compared to prior research at this and nearby southeast Wyoming sites. Nitrogen was lost below the major rooting zone to hillslope groundwater, where dissolved organic nitrogen (DON) increased by 3-10 times (mean 1.65 mg L-1) and NO3-N increased more than 100-fold (3.68 mg L-1) compared to preinfestation concentrations. Most of this N was removed as hillslope groundwater drained through riparian soils, and NO3 remained low in streams. DON entering the stream decreased 50% within 5 km downstream, to concentrations typical of unimpacted subalpine streams (~0.3 mg L-1). Although beetle outbreak caused hillslope N losses similar to other disturbances, up to 5.5 kg ha-1y-1, riparian and in-stream removal limited headwater catchment export to <1 kg ha-1y-1. These observations suggest riparian removal was the dominant mechanism preventing hillslope N loss from impacting streams.

  14. Nor-hopanes from Zanha africana root bark with toxicity to bruchid beetles.

    PubMed

    Stevenson, Philip C; Green, Paul W C; Veitch, Nigel C; Farrell, Iain W; Kusolwa, Paul; Belmain, Steven R

    2016-03-01

    Zanha africana (Radlk.) Exell (Sapindaceae) root bark is used by farmers throughout sub-Saharan Africa to protect stored grain from bruchid beetles, such as Callosobruchus maculatus. Chloroform, methanol and water extracts of Z. africana root bark inhibited oviposition and caused significantly higher mortality of C. maculatus at a rate of application equivalent to that applied by farmers compared to control insects. The chloroform extract contained nor-hopanes rarely found in plants of which seven were isolated, one of which was previously known. Two of the most abundant nor-hopanes 3β,6β-dihydroxy-7β-[(4-hydroxybenzoyl)oxy]-21αH-24-norhopa-4(23),22(29)-diene and 3β,6β-dihydroxy-7β-[(4-hydroxybenzoyl)oxy]-24-norhopa-4(23),17(21)-diene were toxic to and reduced oviposition of C. maculatus in a dose dependent manner. Z. africana root bark is rich in insecticidal compounds that account for its effective use by smallholder farmers as an alternative to conventional insecticides.

  15. Menzbieria chalcographi, a new neogregarine pathogen of the great spruce bark beetle, Dendroctonus micans (Kugelann) (Curculionidae, Scolytinae).

    PubMed

    Yaman, Mustafa; Radek, Renate

    2012-09-01

    This study concerns a new neogregarine parasitic in the great spruce bark beetle Dendroctonus micans (Kugelann) (Curculionidae, Scolytinae). The rate of infection was high, reaching 27.3%. There was no difference in the rate of infection of male and female beetles. The life-cycle stages of the pathogen were described by light and electron microscopy. Each gametocyst of the neogregarine included 8-16 actinocephalid oocysts measuring 11.19 ± 0.42 × 4.99 ± 0.25 μm. The described pathogen has the typical characteristics of members of the genus Menzbieria within the order Neogregarinida and it was identified as Menzbieria chalcographi. This is the first record of an infection of D. micans by M. chalcographi. Possibly, this pathogen could be useful for the biological control of this destructive bark beetle.

  16. Spatiotemporal patterns of observed bark beetle-caused tree mortality in British Columbia and the western United States.

    PubMed

    Meddens, Arjan J H; Hicke, Jeffrey A; Ferguson, Charles A

    2012-10-01

    Outbreaks of aggressive bark beetle species cause widespread tree mortality, affecting timber production, wildlife habitat, wildfire, forest composition and structure, biogeochemical cycling, and biogeophysical processes. As a result, agencies responsible for forest management in the United States and British Columbia conduct aerial surveys to map these forest disturbances. Here we combined aerial surveys from British Columbia (2001 2010) and the western conterminous United States (1997-2010), produced 1-km2 grids of the area of crown mortality from bark beetle attack, and analyzed spatial and temporal patterns. We converted aerial-survey polygon data for each combination of host type and bark beetle species available in the western United States, and for each bark beetle species available in British Columbia. We converted affected area (which includes live and killed trees) to mortality area (crown area of killed trees) using species-specific crown diameters and the number (U.S.) or percentage (British Columbia) of killed trees. In the United States we also produced an upper estimate of mortality area by forcing the mortality area to match that from high-resolution imagery in Idaho, Colorado, and New Mexico. Resulting adjustment factors of 3.7-20.9 illustrate the underestimate of mortality by the U.S. aerial surveys. The upper estimate, which we suggest is more realistic, better matched the spatial patterns and severity of the British Columbia mortality area. Cumulative mortality area from all bark beetles was 5.46 Mha in British Columbia in 2001-2010 and 0.47-5.37 Mha (lower and upper estimate) in the western conterminous United States during 1997-2010. We note that we report year of detection here; studies that consider year of tree mortality should shift the time series back one year. We conclude by discussing uses and limitations of these data in ecological studies, including uncertainties associated with assumptions in the methods, lack of complete coverage

  17. Delayed conifer mortality after fuel reduction treatments: Interactive effects of fuel, fire intensity, and bark beetles

    USGS Publications Warehouse

    Youngblood, A.; Grace, J.B.; Mciver, J.D.

    2009-01-01

    Many low-elevation dry forests of the western United States contain more small trees and fewer large trees, more down woody debris, and less diverse and vigorous understory plant communities compared to conditions under historical fire regimes. These altered structural conditions may contribute to increased probability of unnaturally severe wildfires, susceptibility to uncharacteristic insect outbreaks, and drought-related mortality. Broad-scale fuel reduction and restoration treatments are proposed to promote stand development on trajectories toward more sustainable structures. Little research to date, however, has quantified the effects of these treatments on the ecosystem, especially delayed and latent tree mortality resulting directly or indirectly from treatments. In this paper, we explore complex hypotheses relating to the cascade of effects that influence ponderosa pine (Pinus ponderosa) and Douglas-fir (Pseudotsuga menziesii) mortality using structural equation modeling (SEM). We used annual census and plot data through six growing seasons after thinning and four growing seasons after burning from a replicated, operational-scale, completely randomized experiment conducted in northeastern Oregon, USA, as part of the national Fire and Fire Surrogate study. Treatments included thin, burn, thin followed by burn (thin+burn), and control. Burn and thin+burn treatments increased the proportion of dead trees while the proportion of dead trees declined or remained constant in thin and control units, although the density of dead trees was essentially unchanged with treatment. Most of the new mortality (96%) occurred within two years of treatment and was attributed to bark beetles. Bark beetle-caused tree mortality, while low overall, was greatest in thin + burn treatments. SEM results indicate that the probability of mortality of large-diameter ponderosa pine from bark beetles and wood borers was directly related to surface fire severity and bole charring, which in

  18. The impact of bark beetle infestations on monoterpene emissions and secondary organic aerosol formation in western North America

    NASA Astrophysics Data System (ADS)

    Berg, A. R.; Heald, C. L.; Huff Hartz, K. E.; Hallar, A. G.; Meddens, A. J. H.; Hicke, J. A.; Lamarque, J.-F.; Tilmes, S.

    2013-03-01

    Over the last decade, extensive beetle outbreaks in western North America have destroyed over 100 000 km2 of forest throughout British Columbia and the western United States. Beetle infestations impact monoterpene emissions through both decreased emissions as trees are killed (mortality effect) and increased emissions in trees under attack (attack effect). We use 14 yr of beetle-induced tree mortality data together with beetle-induced monoterpene emission data in the National Center for Atmospheric Research (NCAR) Community Earth System Model (CESM) to investigate the impact of beetle-induced tree mortality and attack on monoterpene emissions and secondary organic aerosol (SOA) formation in western North America. Regionally, beetle infestations may have a significant impact on monoterpene emissions and SOA concentrations, with up to a 4-fold increase in monoterpene emissions and up to a 40% increase in SOA concentrations in some years (in a scenario where the attack effect is based on observed lodgepole pine response). Responses to beetle attack depend on the extent of previous mortality and the number of trees under attack in a given year, which can vary greatly over space and time. Simulated enhancements peak in 2004 (British Columbia) and 2008 (US). Responses to beetle attack are shown to be substantially larger (up to a 3-fold localized increase in summertime SOA concentrations) in a scenario based on bark-beetle attack in spruce trees. Placed in the context of observations from the IMPROVE network, the changes in SOA concentrations due to beetle attack are in most cases small compared to the large annual and interannual variability in total organic aerosol which is driven by wildfire activity in western North America. This indicates that most beetle-induced SOA changes are not likely detectable in current observation networks; however, these changes may impede efforts to achieve natural visibility conditions in the national parks and wilderness areas of the

  19. Multigene phylogenies and morphological characterization of five new Ophiostoma spp. associated with spruce-infesting bark beetles in China.

    PubMed

    Yin, Mingliang; Wingfield, Michael J; Zhou, Xudong; de Beer, Z Wilhelm

    2016-04-01

    Ophiostoma spp. (Ophiostomatales, Ascomycota) are well-known fungi associated with bark beetles (Coleoptera: Scolytinae). Some of these are serious tree pathogens, while the majority is blue-stain agents of timber. In recent years, various bark beetle species have been attacking spruce forests in Qinghai province, China, causing significant damage. A preliminary survey was done to explore the diversity of the ophiostomatoid fungal associates of these beetles. The aims of the present study were to identify and characterize new Ophiostoma spp. associated with spruce-infesting bark beetles in Qinghai Province, and to resolve phylogenetic relationships of Ophiostoma spp. related to the Chinese isolates, using multigene phylogenetic analyses. Results obtained from four gene regions (ribosomal internal transcribed spacer regions, β-tubulin, calmodulin, translation elongation factor-1α) revealed five new Ophiostoma spp. from Qinghai. These included O. nitidus sp. nov., O. micans sp. nov., and O. qinghaiense sp. nov. in a newly defined O. piceae complex. The other two new species, O. poligraphi sp. nov. and O. shangrilae sp. nov., grouped in the O. brunneo-ciliatum complex. Based on DNA sequence and morphological comparisons, we also show that O. arduennense and O. torulosum are synonyms of O. distortum, while O. setosum is a synonym of O. cupulatum.

  20. 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.

  1. 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

  2. Olfactory responses of Ips duplicatus from inner Mongolia, China to nonhost leaf and bark volatiles.

    PubMed

    Zhang, Q H; Liu, G T; Schlyter, F; Birgersson, G; Anderson, P; Valeur, P

    2001-05-01

    Leaf and bark volatiles from nonhost angiosperm trees were tested on Ips duplicatus by gas chromatographic-electroantennographic detection (GC-EAD) and by pheromone-baited traps in Sweden and Inner Mongolia, China, respectively. GC-EAD analysis of the headspace volatiles from fresh bark chips of Betula pubescens revealed trans-conophthorin, two green leaf volatiles (GLVs): 1-hexanol and (Z)-3-hexen-1-ol, and two C8 alcohols: 3-octanol and 1-octen-3-ol, that consistently elicited antennal responses by I. duplicatus. The identification of these EAD-active compounds was confirmed in further GC-EAD recordings with synthetic mixtures. Antennal responses were also found to synthetic (E)-2-hexen-1-ol and linalool, which have been identified from the leaves of nonhost birch and aspen species. No antennal responses of I. duplicatus were found to hexanal, (E)-2-hexenal, and (Z)-3-hexyl acetates. In field trapping experiments, blends of EAD-active green leaf alcohols or C8 alcohols, or transconophthorin alone resulted in significant reductions (27-60%) in the number of I. duplicatus captured compared with pheromone-baited traps. The unsuitable host compound, verbenone (Vn), also significantly reduced trap catches by up to 60% in both experiments. The strongest disruptive effect resulted from the addition of the combination of green leaf alcohols, C8 alcohols, and verbenone to the pheromone trap, which caused an 84% reduction in trap catch. The blend of two green leaf aldehydes plus the acetate increased the trap catches in 1998 and had no negative or positive effects in 1999. Our results suggest that these nonhost volatiles (NHVs) are important olfactory signals used by I. duplicatus in host selection. They may have great significance in developing semiochemical-based management programs for I. duplicatus by reducing or stopping attacks on suitable hosts.

  3. When the forest dies: the response of forest soil fungi to a bark beetle-induced tree dieback.

    PubMed

    Stursová, Martina; Snajdr, Jaroslav; Cajthaml, Tomáš; Bárta, Jiří; Santrůčková, Hana; Baldrian, Petr

    2014-09-01

    Coniferous forests cover extensive areas of the boreal and temperate zones. Owing to their primary production and C storage, they have an important role in the global carbon balance. Forest disturbances such as forest fires, windthrows or insect pest outbreaks have a substantial effect on the functioning of these ecosystems. Recent decades have seen an increase in the areas affected by disturbances in both North America and Europe, with indications that this increase is due to both local human activity and global climate change. Here we examine the structural and functional response of the litter and soil microbial community in a Picea abies forest to tree dieback following an invasion of the bark beetle Ips typographus, with a specific focus on the fungal community. The insect-induced disturbance rapidly and profoundly changed vegetation and nutrient availability by killing spruce trees so that the readily available root exudates were replaced by more recalcitrant, polymeric plant biomass components. Owing to the dramatic decrease in photosynthesis, the rate of decomposition processes in the ecosystem decreased as soon as the one-time litter input had been processed. The fungal community showed profound changes, including a decrease in biomass (2.5-fold in the litter and 12-fold in the soil) together with the disappearance of fungi symbiotic with tree roots and a relative increase in saprotrophic taxa. Within the latter group, successive changes reflected the changing availability of needle litter and woody debris. Bacterial biomass appeared to be either unaffected or increased after the disturbance, resulting in a substantial increase in the bacterial/fungal biomass ratio.

  4. When the forest dies: the response of forest soil fungi to a bark beetle-induced tree dieback

    PubMed Central

    Štursová, Martina; Šnajdr, Jaroslav; Cajthaml, Tomáš; Bárta, Jiří; Šantrůčková, Hana; Baldrian, Petr

    2014-01-01

    Coniferous forests cover extensive areas of the boreal and temperate zones. Owing to their primary production and C storage, they have an important role in the global carbon balance. Forest disturbances such as forest fires, windthrows or insect pest outbreaks have a substantial effect on the functioning of these ecosystems. Recent decades have seen an increase in the areas affected by disturbances in both North America and Europe, with indications that this increase is due to both local human activity and global climate change. Here we examine the structural and functional response of the litter and soil microbial community in a Picea abies forest to tree dieback following an invasion of the bark beetle Ips typographus, with a specific focus on the fungal community. The insect-induced disturbance rapidly and profoundly changed vegetation and nutrient availability by killing spruce trees so that the readily available root exudates were replaced by more recalcitrant, polymeric plant biomass components. Owing to the dramatic decrease in photosynthesis, the rate of decomposition processes in the ecosystem decreased as soon as the one-time litter input had been processed. The fungal community showed profound changes, including a decrease in biomass (2.5-fold in the litter and 12-fold in the soil) together with the disappearance of fungi symbiotic with tree roots and a relative increase in saprotrophic taxa. Within the latter group, successive changes reflected the changing availability of needle litter and woody debris. Bacterial biomass appeared to be either unaffected or increased after the disturbance, resulting in a substantial increase in the bacterial/fungal biomass ratio. PMID:24671082

  5. Simple and Efficient Trap for Bark and Ambrosia Beetles (Coleoptera: Curculionidae) to Facilitate Invasive Species Monitoring and Citizen Involvement.

    PubMed

    Steininger, M S; Hulcr, J; Šigut, M; Lucky, A

    2015-06-01

    Bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae & Platypodinae) are among the most damaging forest pests worldwide, and monitoring is essential to damage prevention. Unfortunately, traps and attractants that are currently used are costly, and agencies rely on limited field personnel for deployment. The situation can be greatly aided by 1) the development of cost-effective trapping techniques, and 2) distribution of the effort through the Citizen Science approach. The goal of this study was to test a simple, effective trap that can be made and deployed by anyone interested in collecting bark and ambrosia beetles. Three trap types made from 2-liter soda bottles and, separately, four attractants were compared. Simple, one-window traps performed comparably at capturing species in traps painted or with multiple windows. A comparison of attractants in two-window traps found that 95% ethanol attracted the highest number of species but that Purell hand sanitizer (70% ethanol) and then Germ-X hand sanitizer (63% ethanol) were also effective. A perforated zip-top plastic bag containing Purell hanging over a trap filled with automobile antifreeze attracted the fewest species and individual specimens. Overall, >4,500 bark and ambrosia beetles, including 30 species were captured, representing a third of the regional species diversity. More than three quarters of the specimens were nonnative, representing nearly half of the known regional exotic species. These results suggest that simple one-window soda bottle traps baited with ethanol-based hand sanitizer will be effective and inexpensive tools for large-scale monitoring of bark and ambrosia beetles.

  6. Bark beetle and wood borer infestation in the greater Yellowstone area during four postfire years. Forest Service research paper

    SciTech Connect

    Rasmussen, L.A.; Amman, G.D.; Vandygriff, J.C.; Oakes, R.D.; Munson, A.S.

    1996-03-01

    Surveys of bark beetle and wood borer infestation in the Greater Yellowstone Area were conducted from 1991 through 1993 to determine the effect of delayed tree mortality on mosaics of fire-killed and green tree stands, the relationship between fire injury and infestation, but both types of mortality greatly altered the mosaics immediately apparent after the 1988 fires. The high level of infestation suggests that insects built up in fire-injured trees and then caused increased infestation of uninjured trees.

  7. Influence of recent bark beetle outbreak on fire severity and postfire tree regeneration in montane Douglas-fir forests.

    PubMed

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

    2013-11-01

    Understanding how disturbances interact to shape ecosystems is a key challenge in ecology. In forests of western North America, the degree to which recent bark beetle outbreaks and subsequent fires may be linked (e.g., outbreak severity affects fire severity) and/ or whether these two disturbances produce compound effects on postfire succession is of widespread interest. These interactions remain unresolved, largely because field data from actual wildfires following beetle outbreaks are lacking. We studied the 2008 Gunbarrel Fire, which burned 27 200 ha in Douglas-fir (Pseudotsuga menziesii) forests that experienced a bark beetle outbreak 4-13 years prefire ("gray stage," after trees have died and needles have dropped), to determine whether outbreak severity influenced subsequent fire severity and postfire tree regeneration. In 85 sample plots we recorded prefire stand structure and outbreak severity; multiple measures of canopy and forest-floor fire severity; and postfire tree seedling density. Prefire outbreak severity was not related to any measure of fire severity except for mean bole scorch, which declined slightly with increasing outbreak severity. Instead, fire severity varied with topography and burning conditions (proxy for weather at time of fire). Postfire Douglas-fir regeneration was low, with tree seedlings absent in 65% of plots. Tree seedlings were abundant in plots of low fire severity that also had experienced low outbreak severity (mean = 1690 seedlings/ha), suggesting a dual filter on tree regeneration. Although bark beetles and fire collectively reduced live basal area to < 5% and increased snag density to > 2000% of pre-outbreak levels, the lack of relationship between beetle outbreak and fire severity suggests that these disturbances were not linked. Nonetheless, effects on postfire tree regeneration suggest compound disturbance interactions that contribute to the structural heterogeneity characteristic of mid/lower montane forests.

  8. Fungal diversity of Norway spruce litter: effects of site conditions and premature leaf fall caused by bark beetle outbreak.

    PubMed

    Przybył, K; Karolewski, P; Oleksyn, J; Labedzki, A; Reich, P B

    2008-08-01

    Fungi play an important role in leaf litter decomposition due to their ability to break down the lignocellulose matrix, which other organisms are unable to digest. However, little is known regarding the factors affecting components of fungal diversity. Here, we quantified richness of internal fungi in relation to litter nutrient and phenolic concentrations, sampling season (spring or fall), and premature leaf shedding due to low precipitation and infestation of bark beetles (mainly Ips typographus and Ips duplicatus). The study was conducted in 37-year-old Norway spruce [Picea abies (L.) Karst.] stands, with three plots each in mixed forest (MF) and coniferous forest (CF) site conditions in south-central Poland. Fifty-four species of sporulating fungi were identified in 2,330 freshly fallen needles sampled during 2003-2005, including 45 species in MF and 31 in CF. The significantly higher number of species in MF was likely related to moister conditions at that site. Among isolated fungi, 22% (12 species) were identified as endophytes of Norway spruce in prior studies. During spring of 2005, we found less than half the number of isolates and fungal species at each forest site as compared to fall for the two prior years. This pattern was observed in typical soil fungi (e.g., Penicillium daleae, Penicillium purpurogenum) and endophytes/epiphytes (e.g., Aureobasidium pullulans, Alternaria alternata, Cladosporium spp., and Lophodermium piceae). Premature shedding of needles was the most likely cause of this decline because it shortened the time period for fungi to infect green needles while on the tree. For all sites and sampling periods, richness of internal fungi was strongly and positively related to the age of freshly fallen litter (assessed using needle Ca concentration as a needle age tracer) and was also negatively related to litter phenolic concentration. Richness of internal fungi in freshly fallen litter may be adversely affected by low soil moisture status

  9. Gene discovery for the bark beetle-vectored fungal tree pathogen Grosmannia clavigera

    PubMed Central

    2010-01-01

    Background Grosmannia clavigera is a bark beetle-vectored fungal pathogen of pines that causes wood discoloration and may kill trees by disrupting nutrient and water transport. Trees respond to attacks from beetles and associated fungi by releasing terpenoid and phenolic defense compounds. It is unclear which genes are important for G. clavigera's ability to overcome antifungal pine terpenoids and phenolics. Results We constructed seven cDNA libraries from eight G. clavigera isolates grown under various culture conditions, and Sanger sequenced the 5' and 3' ends of 25,000 cDNA clones, resulting in 44,288 high quality ESTs. The assembled dataset of unique transcripts (unigenes) consists of 6,265 contigs and 2,459 singletons that mapped to 6,467 locations on the G. clavigera reference genome, representing ~70% of the predicted G. clavigera genes. Although only 54% of the unigenes matched characterized proteins at the NCBI database, this dataset extensively covers major metabolic pathways, cellular processes, and genes necessary for response to environmental stimuli and genetic information processing. Furthermore, we identified genes expressed in spores prior to germination, and genes involved in response to treatment with lodgepole pine phloem extract (LPPE). Conclusions We provide a comprehensively annotated EST dataset for G. clavigera that represents a rich resource for gene characterization in this and other ophiostomatoid fungi. Genes expressed in response to LPPE treatment are indicative of fungal oxidative stress response. We identified two clusters of potentially functionally related genes responsive to LPPE treatment. Furthermore, we report a simple method for identifying contig misassemblies in de novo assembled EST collections caused by gene overlap on the genome. PMID:20920358

  10. Soil carbon cycle 13C responses in the decade following bark beetle and girdling disturbance

    NASA Astrophysics Data System (ADS)

    Maurer, G. E.; Chan, A. M.; Trahan, N. A.; Moore, D. J.; Bowling, D. R.

    2014-12-01

    Recent bark beetle outbreaks in western North America have impacted millions of hectares of conifer forests leading to uncertainty about whether these forests will become new sources of atmospheric CO2. In large part, this depends on whether enhanced respiration from the decomposition of newly dead organic matter will outpace the recovery of ecosystem carbon uptake by the ecosystems. To understand how rapidly conifer forest carbon pools turn over following these disturbances, we examined changes in the isotopic composition of soil respiration (δ13Cresp) following beetle and girdling mortality in two subalpine forests in Colorado, U.S.A. At the beetle-impacted forest δ13Cresp declined by ~1‰ between 3 and 8 years post-disturbance, but recovered in years 9-10. In the girdled forest, deep (<10 cm depth) soil respiration from plots at <1 to 2 years post-girdling was depleted by ~1‰ relative to ungirdled plots, but then gradually increased until there was a significant spike in δ13Cresp at 8-9 years post-girdling. Based on our understanding of isotopic composition in carbon pools and fluxes at these forests, we attribute these changes to removal of recently assimilated C in rhizosphere respiration (1-2 years) followed by the decomposition of litterfall (needles and roots) 8-10 years post-disturbance. Relative to ungirdled plots, there was also a transient enrichment in surface δ13Cresp from plots at <1 to 2 years post-girdling (~0.5‰, not statistically significant) and significant declines in microbial carbon in surface soils in 2-4 year post-girdling plots. Again, based on current understanding, we interpret these to signify the rapid turnover of mycorrhizal and rhizosphere microbial biomass in the 2 years following girdling. A potential confounding factor in this study is that seasonal variation in δ13Cresp was similar in magnitude to changes with time since disturbance and was significantly related to variation in soil temperature and water content.

  11. Phylogeography reveals routes of colonization of the bark beetle Dendroctonus approximatus Dietz in Mexico.

    PubMed

    Sánchez-Sánchez, Hermilo; López-Barrera, Gabriela; Peñaloza-Ramírez, Juan Manuel; Rocha-Ramírez, Víctor; Oyama, Ken

    2012-01-01

    We used mitochondrial DNA (mtDNA) sequence data and allele frequencies at eight microsatellite loci to examine the population genetic structure, estimate the divergence times of distinct lineages, and infer patterns associated with host colonization in populations of the bark beetle Dendroctonus approximatus in Mexico. Two haplotype groups were identified using mtDNA sequences in 71 individuals from 15 populations. The first group was distributed in the Sierra Madre Occidental (SMOc, Western Mexico), with some populations in the Faja Volcánica Transmexicana (Central Mexico), and the second was found in the Sierra Madre Oriental (SMOr, Eastern Mexico), with populations in the Sierra Madre del Sur (Southern Mexico). The estimated split between groups occurred in the late Pleistocene, around 0.195 Mya. Microsatellite allele frequencies revealed high genetic differentiation between pairwise populations, and genetic differentiation values indicated a genetic structure of isolation by distance. Both mtDNA sequence data and microsatellite allele frequencies indicated that D. approximatus had two independent colonization routes in Mexico, one through the SMOc and another along the SMOr. The widespread geographic distribution of D. approximatus in Mexico follows a model of population range expansion of two haplotype groups in which gene flow is restricted by the geographic separation between hosts imposed by physical barriers between populations.

  12. Seasonal water stress and the resistance of Pinus yunnanensis to a bark-beetle-associated fungus.

    PubMed

    Salle, Aurelien; Ye, Hui; Yart, Annie; Lieutier, François

    2008-05-01

    We examined the influence of seasonal water stress on the resistance of Pinus yunnanensis (Franch.) to inoculation with Leptographium yunnanense, a pathogenic fungus associated with the aggressive bark beetle, Tomicus n. sp. Experiments took place between October 1997 and November 1999 in two plots located at the top and at the foot of a hill in Shaogiu, China, a region characterized by dry winters and wet summers. Following isolated and mass fungal inoculations, we observed the reaction zone length, fungal growth in the phloem, and the occlusion, blue-staining and specific hydraulic conductivity of the sapwood. Measurements of soil and needle water contents and predawn needle water potentials confirmed that trees were subject to mild water stress during winter, especially at the drier hilltop site. Measures of tree resistance to fungal infection of phloem and sapwood were congruent and indicated that trees were most susceptible to inoculation during the wet summer, especially at the lower-elevation plot. Specific hydraulic conductivity decreased after inoculation in summer. The results indicate that mild seasonal water stress is not likely responsible for the recent extensive damage to young P. yunnanensis stands by Tomicus n. sp. in the vicinity of our study plots. Rather, the results suggest that mild water stress enhances tree resistance to fungal pathogens associated with Tomicus n. sp.

  13. The Response of Subalpine Vegetation to Climate Change and Bark Beetle Infestations: A Multi-Scale Interaction.

    NASA Astrophysics Data System (ADS)

    Foster, A.; Shuman, J. K.; Shugart, H. H., Jr.; Negrón, J. F.

    2015-12-01

    Mean annual temperatures in the western United States have increased in the last few decades, and are predicted to continue warming. In the subalpine zone of the Rocky Mountains, this warming is also predicted to increase the frequency and severity of spruce beetle outbreaks. Climate change itself may affect this vegetation, potentially leading to shifts in species compositions. These forests are a crucial part of the US's carbon budget, thus it is important to analyze how climate change and bark beetles in conjunction will affect the biomass and species composition of vegetation in subalpine zone. UVAFME is an individual-based gap model that simulates biomass and species composition of a forest. This model has been quantitatively tested at various Rocky Mountain sites in the Front Range, and has been shown to accurately simulate the vegetation dynamics in the region. UVAFME has been updated with a spruce beetle subroutine that calculates the probability for beetle infestation of each tree on a plot. This probability is based on site, climate, and individual tree characteristics, such as temperature; stand structure; and tree stress level, size, and age. These governing characteristics are based on data from the US Forest Service, and other studies on spruce susceptibility and spruce beetle phenology. UVAFME is then run with multiple climate change and beetle scenarios to determine the net effect of both variables on subalpine vegetation. These results are compared among the different scenarios and to current forest inventory data. We project that increasing temperatures due to climate change will cause an increase in the frequency and severity of spruce beetle outbreaks, leading to a decrease in the biomass and dominance of Engelmann spruce. These results are an important step in understanding the possible futures for the vegetation of subalpine zone in the Rocky Mountains.

  14. Trees Wanted—Dead or Alive! Host Selection and Population Dynamics in Tree-Killing Bark Beetles

    PubMed Central

    Kausrud, Kyrre L.; Grégoire, Jean-Claude; Skarpaas, Olav; Erbilgin, Nadir; Gilbert, Marius; Økland, Bjørn; Stenseth, Nils Chr.

    2011-01-01

    Bark beetles (Coleoptera: Curculionidae, Scolytinae) feed and breed in dead or severely weakened host trees. When their population densities are high, some species aggregate on healthy host trees so that their defences may be exhausted and the inner bark successfully colonized, killing the tree in the process. Here we investigate under what conditions participating with unrelated conspecifics in risky mass attacks on living trees is an adaptive strategy, and what this can tell us about bark beetle outbreak dynamics. We find that the outcome of individual host selection may deviate from the ideal free distribution in a way that facilitates the emergence of tree-killing (aggressive) behavior, and that any heritability on traits governing aggressiveness seems likely to exist in a state of flux or cycles consistent with variability observed in natural populations. This may have implications for how economically and ecologically important species respond to environmental changes in climate and landscape (forest) structure. The population dynamics emerging from individual behavior are complex, capable of switching between “endemic” and “epidemic” regimes spontaneously or following changes in host availability or resistance. Model predictions are compared to empirical observations, and we identify some factors determining the occurrence and self-limitation of epidemics. PMID:21647433

  15. Trees wanted--dead or alive! Host selection and population dynamics in tree-killing bark beetles.

    PubMed

    Kausrud, Kyrre L; Grégoire, Jean-Claude; Skarpaas, Olav; Erbilgin, Nadir; Gilbert, Marius; Økland, Bjørn; Stenseth, Nils Chr

    2011-01-01

    Bark beetles (Coleoptera: Curculionidae, Scolytinae) feed and breed in dead or severely weakened host trees. When their population densities are high, some species aggregate on healthy host trees so that their defences may be exhausted and the inner bark successfully colonized, killing the tree in the process. Here we investigate under what conditions participating with unrelated conspecifics in risky mass attacks on living trees is an adaptive strategy, and what this can tell us about bark beetle outbreak dynamics. We find that the outcome of individual host selection may deviate from the ideal free distribution in a way that facilitates the emergence of tree-killing (aggressive) behavior, and that any heritability on traits governing aggressiveness seems likely to exist in a state of flux or cycles consistent with variability observed in natural populations. This may have implications for how economically and ecologically important species respond to environmental changes in climate and landscape (forest) structure. The population dynamics emerging from individual behavior are complex, capable of switching between "endemic" and "epidemic" regimes spontaneously or following changes in host availability or resistance. Model predictions are compared to empirical observations, and we identify some factors determining the occurrence and self-limitation of epidemics.

  16. Description of Phloeosinus laricionis sp. n. (Coleoptera: Curculionidae, Scolytinae), a new bark beetle species from southern Europe.

    PubMed

    Faccoli, Massimo; Sidoti, Agatino

    2013-01-01

    We describe a new species of pine bark beetle, Phloeosinus laricionis, associated with a pine decline recently affecting young plantations of Pinus nigra ssp. laricio Poiret growing on the Etna volcano, Sicily (South Italy). The new species is morphologically close to the group species of P. cedri Brisout, P. acatayi Schedl, and P. pfefferi Knížek, having all odd interstriae on the declivity of elytra bearing small, individual, sparse, more or less sharply pointed tubercles in males, or with smaller sparse blunt, nippled tubercles in females. While the other species of the same group live on cedars, the new species is the only Palaearctic Phloeosinus known from pine.

  17. Ecological Study of Nematode Parasitism in Ips Beetles from California and Idaho

    PubMed Central

    Choo, Ho Yul; Kaya, Harry K.; Shea, Patrick; Noffsinger, E. Mae

    1987-01-01

    Nematodes found in Ips paraconfusus from ponderosa pine in California were an undescribed species of Parasitaphelenchus, Contortylenchus elongatus, C. reversus, and C. brevicomi. C. elongatus, the most commonly found contortylenchid, was present in 98.2% of the contortylenchid-parasitized beetles. Only one nematode parasite of the gut, a Parasitorhabditis sp., was isolated. Although significant differences in parasitism were observed, they were by collection sites, rather than by elevation or bole sources (slash or standing). Significant changes in parasitism between fall and spring collections were observed but not at every site. Nematode parasitism in the F₁ generation of I. paraconfusus by Parasitaphelenchus, Contortylenchus, or Parasitorhabditis increased or decreased from the parent generation depending upon the experiment. Nematode parasites from I. pini included an undescribed Parasitaphelenchus sp., two undescribed Contortylenchus spp., C. reversus and Parasitylenchus (= Neoparasitylenchus) ovarius from the hemocel, and Parasitorhabditis ipini from the gut. Parasitaphelenchus sp. was found in 99% and 45.3% of the beetles from Idaho and California, respectively. Of the 1,000 I. pini from Idaho and California, 157 were parasitized by the contortylenchid species or P. ovarius. PMID:19290176

  18. Hyperspectral interferometry: Sizing microscale surface features in the pine bark beetle.

    PubMed

    Beach, James M; Uertz, James L; Eckhardt, Lori G

    2015-10-01

    A new method of interferometry employing a Fabry-Perot etalon model was used to locate and size microscale features on the surface of the pine bark beetle. Oscillations in the reflected light spectrum, caused by self-interference of light reflecting from surfaces of foreleg setae and spores on the elytrum, were recorded using white light hyperspectral microscopy. By making the assumption that pairs of reflecting surfaces produce an etalon effect, the distance between surfaces could be determined from the oscillation frequency. Low frequencies of less than 0.08 nm(-1) were observed in the spectrum below 700 nm while higher frequencies generally occupied wavelengths from 600 to 850 nm. In many cases, two frequencies appeared separately or in combination across the spectrum. The etalon model gave a mean spore size of 3.04 ± 1.27 μm and a seta diameter of 5.44 ± 2.88 μm. The tapering near the setae tip was detected as a lowering of frequency. Spatial fringes were observed together with spectral oscillations from surfaces on the exoskeleton at higher magnification. These signals were consistent with embedded multi-layer reflecting surfaces. Possible applications for hyperspectral interferometry include medical imaging, detection of spore loads in insects and other fungal carriers, wafer surface and subsurface inspection, nanoscale materials, biological surface analysis, and spectroscopy calibration. This is, to our knowledge, the first report of oscillations directly observed by microscopy in the reflected light spectra from Coleoptera, and the first demonstration of broadband hyperspectral interferometry using microscopy that does not employ an internal interferometer.

  19. Pseudomonas coleopterorum sp. nov., a cellulase-producing bacterium isolated from the bark beetle Hylesinus fraxini.

    PubMed

    Menéndez, Esther; Ramírez-Bahena, Martha H; Fabryová, Anna; Igual, José M; Benada, Oldrich; Mateos, Pedro F; Peix, Alvaro; Kolařík, Miroslav; García-Fraile, Paula

    2015-09-01

    We isolated a strain coded Esc2Am(T) during a study focused on the microbial diversity of adult specimens of the bark beetle Hylesinus fraxini. Its 16S rRNA gene sequence had 99.4% similarity with respect to its closest relative, Pseudomonas rhizosphaerae IH5(T). The analysis of partial sequences of the housekeeping genes rpoB, rpoD and gyrB confirmed that strain Esc2Am(T) formed a cluster with P. rhizosphaerae IH5(T) clearly separated from the remaining species of the genus Pseudomonas. Strain Esc2Am(T) had polar flagella and could grow at temperatures from 4 °C to 30 °C. The respiratory quinone was Q9 and the main fatty acids were C16 : 0, C18 : 1ω7c and/or C18 : 1ω6c in summed feature 8 and C16 : 1ω7c and/or C16 : 1ω6c in summed feature 3. DNA-DNA hybridization results showed 51% relatedness with respect to P. rhizosphaerae IH5(T). Oxidase, catalase and urease-positive, the arginine dihydrolase system was present but nitrate reduction and β-galactosidase production were negative. Aesculin hydrolysis was positive. Based on the results from the genotypic, phenotypic and chemotaxonomic analyses, we propose the classification of strain Esc2Am(T) as representing a novel species of the genus Pseudomonas, for which we propose the name Pseudomonas coleopterorum sp. nov. The type strain is Esc2Am(T) ( = LMG 28558(T)= CECT 8695(T)).

  20. Bark and ambrosia beetles (Curculionidae: Scolytinae), their phoretic mites (Acari) and associated Geosmithia species (Ascomycota: Hypocreales) from Virgilia trees in South Africa.

    PubMed

    Machingambi, Netsai M; Roux, Jolanda; Dreyer, Léanne L; Roets, Francois

    2014-01-01

    Bark and ambrosia beetles are ecologically and economically important phloeophagous insects that often have complex symbiotic relationships with fungi and mites. These systems are greatly understudied in Africa. In the present study we identified bark and ambrosia beetles, their phoretic mites and their main fungal associates from native Virgilia trees in the Cape Floristic Region (CFR) of South Africa. In addition, we tested the ability of mites to feed on the associated fungi. Four species of scolytine beetles were collected from various Virgilia hosts and from across the CFR. All were consistently associated with various Geosmithia species, fungi known from phloeophagous beetles in many parts of the world, but not yet reported as Scolytinae associates in South Africa. Four beetle species, a single mite species and five Geosmithia species were recovered. The beetles, Hapalogenius fuscipennis, Cryphalini sp. 1, and Scolytoplatypus fasciatus were associated with a single species of Elattoma phoretic mite that commonly carried spores of Geosmithia species. Liparthrum sp. 1 did not carry phoretic mites. Similar to European studies, Geosmithia associates of beetles from Virgilia were constant over extended geographic ranges, and species that share the same host plant individual had similar Geosmithia communities. Phoretic mites were unable to feed on their Geosmithia associates, but were observed to feed on bark beetle larvae within tunnels. This study forms the first African-centred base for ongoing global studies on the associations between arthropods and Geosmithia species. It strengthens hypotheses that the association between Scolytinae beetles and dry-spored Geosmithia species may be more ubiquitous than commonly recognised.

  1. Pheromone-Mediated Mate Location and Discrimination by Two Syntopic Sibling Species of Dendroctonus Bark Beetles in Chiapas, Mexico.

    PubMed

    Niño-Domínguez, Alicia; Sullivan, Brian T; López-Urbina, José H; Macías-Sámano, Jorge E

    2015-08-01

    Where their geographic and host ranges overlap, sibling species of tree-killing bark beetles may simultaneously attack and reproduce on the same hosts. However, sustainability of these potentially mutually beneficial associations demands effective prezygotic reproductive isolation mechanisms between the interacting species. The pine bark beetle, Dendroctonus frontalis Zimmermann, is syntopic in the Central American region with a recently described sibling species, Dendroctonus mesoamericanus Armendáriz-Toledano and Sullivan, but mechanisms for their reproductive isolation are uncertain. We investigated whether semiochemicals mediate species discrimination by mate-seeking males of both species. In olfactometer bioassays, walking males of both species strongly preferred odors from gallery entrances of conspecific females. Coupled gas chromatography-electroantennographic detection and gas chromatography-mass spectrometry isolated 16 olfactory stimulants for males in these odors, but only two, ipsdienol and endo-brevicomin (both from D. mesoamericanus females), differed in quantity in female-associated odors between the species. In olfactometer bioassays, with 10, 1, or 0.1 female entrance equivalents of synthetic semiochemicals, the combination of ipsdienol and endo-brevicomin inhibited responses of male D. frontalis and enhanced responses of male D. mesoamericanus to two compounds associated with female entrances of both species (the pheromone component frontalin and host odor α-pinene). We conclude that ipsdienol and endo-brevicomin, pheromone components produced by females of just one of the two species (D. mesoamericanus), mediate interspecific mate discrimination by males of both species and provide an apparently symmetrical reproductive isolation mechanism.

  2. DNA barcoding of bark and ambrosia beetles reveals excessive NUMTs and consistent east-west divergence across Palearctic forests.

    PubMed

    Jordal, Bjarte H; Kambestad, Marius

    2014-01-01

    A comprehensive DNA barcoding library is very useful for rapid identification and detection of invasive pest species. We tested the performance of species identification in the economically most damaging group of wood-boring insects - the bark and ambrosia beetles - with particular focus on broad geographical sampling across the boreal Palearctic forests. Neighbour-joining and Bayesian analyses of cytochrome oxidase I (COI) sequences from 151 species in 40 genera revealed high congruence between morphology-based identification and sequence clusters. Inconsistencies with morphological identifications included the discovery of a likely cryptic Nearctic species of Dryocoetes autographus, the possible hybrid origin of shared mitochondrial haplotypes in Pityophthorus micrographus and P. pityographus, and a possible paraphyletic Xyleborinus saxeseni. The first record of Orthotomicus suturalis in North America was confirmed by DNA barcoding. The mitochondrial data also revealed consistent divergence across the Palearctic or Holarctic, confirmed in part by data from the large ribosomal subunit (28S). Some populations had considerable variation in the mitochondrial barcoding marker, but were invariant in the nuclear ribosomal marker. These findings must be viewed in light of the high number of nuclear insertions of mitochondrial DNA (NUMTs) detected in eight bark beetle species, suggesting the possible presence of additional cryptic NUMTs. The occurrence of paralogous COI copies, hybridization or cryptic speciation demands a stronger focus on data quality assessment in the construction of DNA barcoding databases.

  3. Species Boundaries and Host Range of Tortoise Mites (Uropodoidea) Phoretic on Bark Beetles (Scolytinae), Using Morphometric and Molecular Markers

    PubMed Central

    Knee, Wayne; Beaulieu, Frédéric; Skevington, Jeffrey H.; Kelso, Scott; Cognato, Anthony I.; Forbes, Mark R.

    2012-01-01

    Understanding the ecology and evolutionary history of symbionts and their hosts requires accurate taxonomic knowledge, including clear species boundaries and phylogenies. Tortoise mites (Mesostigmata: Uropodoidea) are among the most diverse arthropod associates of bark beetles (Curculionidae: Scolytinae), but their taxonomy and host associations are largely unstudied. We tested the hypotheses that (1) morphologically defined species are supported by molecular data, and that (2) bark beetle uropodoids with a broad host range comprise cryptic species. To do so, we assessed the species boundaries of uropodoid mites collected from 51 host species, across 11 countries and 103 sites, using morphometric data as well as partial cytochrome oxidase I (COI) and nuclear large subunit ribosomal DNA (28S). Overall, morphologically defined species were confirmed by molecular datasets, with a few exceptions. Twenty-nine of the 36 uropodoid species (Trichouropoda, Nenteria and Uroobovella) collected in this study had narrow host ranges, while seven species had putative broad host ranges. In all but one species, U. orri, our data supported the existence of these host generalists, which contrasts with the typical finding that widespread generalists are actually complexes of cryptic specialists. PMID:23071768

  4. Oviposition stimulants for the beetle,Monochamus alternatus hope, in inner bark of pine.

    PubMed

    Yamasaki, T; Sakai, M; Miyawaki, S

    1989-02-01

    Field and laboratory ovipositional responses ofMonochamus alternatus Hope, respectively, to methanol and water extracts from pine inner bark were examined in comparison with those to pine inner bark, especially using a laboratory-built apparatus for the latter bioassay. Irrespective of the existence of volatiles from paraquat-induced lightwood, pine inner bark and its methanol and water extracts stimulated ovipositional response only in the presence of free moisture.

  5. Molecular markers detect cryptic predation on coffee berry borer (Coleoptera: Curculionidae) by silvanid and laemophloeid flat bark beetles (Coleoptera: Silvanidae, Laemophloeidae) in coffee beans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The coffee berry borer, Hypothenemus hampei(Coleoptera: Curculionidae)(Ferrari), is a serious pest of coffee worldwide and has been recently introduced in Hawai’i, first detected in the state in 2010. Adult silvanid flat bark beetles, Cathartus quadricollis (Coleoptera: Silvanidae) and adult laemoph...

  6. Attraction modulated by spacing of pheromone components and anti-attractants in a bark beetle and a moth.

    PubMed

    Andersson, Martin N; Binyameen, Muhammad; Sadek, Medhat M; Schlyter, Fredrik

    2011-08-01

    Orientation for insects in olfactory landscapes with high semiochemical diversity may be a challenging task. The partitioning of odor plumes into filaments that are interspersed with pockets of 'clean air' may help filament discrimination and upwind flight to attractive sources in the face of inhibitory signals. We studied the effect of distance between odor sources on trap catches of the beetle, Ips typographus, and the moth, Spodoptera littoralis. Insects were tested both to spatially separated pheromone components [cis-verbenol and 2-methyl-3-buten-2-ol for Ips; (Z,E)-9,11-tetradecadienyl acetate and (Z,E)-9,12-tetradecadienyl acetate for Spodoptera], and to separated pheromone and anti-attractant sources [non-host volatile (NHV) blend for Ips; (Z)-9-tetradecenyl acetate for Spodoptera]. Trap catch data were complemented with simulations of plume structure and plume overlap from two separated sources using a photo ionization detector and soap bubble generators. Trap catches of the beetle and the moth were both affected when odor sources in the respective traps were increasingly separated. However, this effect on trap catch occurred at smaller (roughly by an order of magnitude) odor source separation distances for the moth than for the beetle. This may reflect differences between the respective olfactory systems and central processing. For both species, the changes in trap catches in response to separation of pheromone components occurred at similar spacing distances as for separation of pheromone and anti-attractant sources. Overlap between two simulated plumes depended on distance between the two sources. In addition, the number of detected filaments and their concentration decreased with downwind distance. This implies that the response to separated odor sources in the two species might take place under different olfactory conditions. Deploying multiple sources of anti-attractant around a pheromone trap indicated long-distance (meter scale) effects of NHV on

  7. Ecological coassociations influence species' responses to past climatic change: an example from a Sonoran Desert bark beetle.

    PubMed

    Garrick, Ryan C; Nason, John D; Fernández-Manjarrés, Juan F; Dyer, Rodney J

    2013-06-01

    Ecologically interacting species may have phylogeographical histories that are shaped both by features of their abiotic landscape and by biotic constraints imposed by their coassociation. The Baja California peninsula provides an excellent opportunity to examine the influence of abiotic vs. biotic factors on patterns of diversity in plant-insect species.This is because past climatic and geological changes impacted the genetic structure of plants quite differently to that of codistributed free-living animals (e.g. herpetofauna and small mammals). Thus, 'plant-like' patterns should be discernible in host-specific insect herbivores. Here, we investigate the population history of a monophagous bark beetle, Araptus attenuatus, and consider drivers of phylogeographical patterns in the light of previous work on its host plant, Euphorbia lomelii. Using a combination of phylogenetic, coalescent-simulation-based and exploratory analyses of mitochondrial DNA sequences and nuclear genotypic data, we found that the evolutionary history of A. attenuatus exhibits similarities to its host plant that are attributable to both biotic and abiotic processes. Southward range expansion and recent colonization of continental Sonora from the Baja peninsula appear to be unique to this taxon pair and probably reflect influences of the host plant. On the other hand, abiotic factors with landscape level influences on a diverse suite of codistributed arid-adapted taxa, such as Plio- and Pleistocene-aged marine incursions in the region, also left genetic signatures in beetle and host plant populations. Superimposed on these similarities, bark beetle-specific patterns and processes were also evident: our data revealed two secondarily sympatric,reproductively isolated genetic lineages, as well as a previously unrecognized mid peninsular warm desert refuge. Taken together, this work illustrates that the evolutionary history of species-specific insect herbivores may represent a mosaic of influences

  8. 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.

  9. Carbon Impacts of Fire- and Bark Beetle-Caused Tree Mortality across the Western US using the Community Land Model (Invited)

    NASA Astrophysics Data System (ADS)

    Meddens, A. J.; Hicke, J. A.; Edburg, S. L.; Lawrence, D. M.

    2013-12-01

    Wildfires and bark beetle outbreaks cause major forest disturbances in the western US, affecting ecosystem productivity and thereby impacting forest carbon cycling and future climate. Despite the large spatial extent of tree mortality, quantifying carbon flux dynamics following fires and bark beetles over larger areas is challenging because of forest heterogeneity, varying disturbance severities, and field observation limitations. The objective of our study is to estimate these dynamics across the western US using the Community Land Model (version CLM4.5-BGC). CLM4.5-BGC is a land ecosystem model that mechanistically represents the exchanges of energy, water, carbon, and nitrogen with the atmosphere. The most recent iteration of the model has been expanded to include vertically resolved soil biogeochemistry and includes improved nitrogen cycle representations including nitrification and denitrification and biological fixation as well as improved canopy processes including photosynthesis. Prior to conducting simulations, we modified CLM4.5-BGC to include the effects of bark beetle-caused tree mortality on carbon and nitrogen stocks and fluxes. Once modified, we conducted paired simulations (with and without) fire- and bark beetle-caused tree mortality by using regional data sets of observed mortality as inputs. Bark beetle-caused tree mortality was prescribed from a data set derived from US Forest Service aerial surveys from 1997 to 2010. Annual tree mortality area was produced from observed tree mortality caused by bark beetles and was adjusted for underestimation. Fires were prescribed using the Monitoring Trends in Burn Severity (MTBS) database from 1984 to 2010. Annual tree mortality area was produced from forest cover maps and inclusion of moderate- and high-severity burned areas. Simulations show that maximum yearly reduction of net ecosystem productivity (NEP) caused by bark beetles is approximately 20 Tg C for the western US. Fires cause similar reductions

  10. 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.

  11. Effects of bark beetle outbreaks on species composition, biomass, and nutrient distribution in a mixed deciduous forest

    SciTech Connect

    Johnson, D.W.; Henderson, G.S.; Harris, W.F.

    1987-01-01

    The increment of forest biomass and nutrient content on Walker Branch Watershed, Tennessee, from 1967 to 1983 was interrupted by two bark beetle outbreaks. An outbreak of the southern pine beetle in the early 1970s and an outbreak of the hickory borer in the late 1970s, early 1980s killed a number of shortleaf pine (Pinus echinata) and hickory (Carya spp.) respectively. Yellow-poplar (Liriodendron tulipifera) growth increased over this 16-year period, especially in response to the mortality of shortleaf pine. The net result of these events was little change in total biomass but a substantial shift in species composition (from pine to yellow-poplar) in the Pine forest type over this period. No species has yet responded to the mortality of hickory. Due to the shift in species composition in the Pine type, calcium and magnesium accumulation rates in biomass increased but foliage biomass decreased over the inventory period. There was little change in foliage biomass or nutrient content in other forest types. The beetle attacks, combined with apparently natural self-thinning, caused a large increase in standing dead biomass and in nutrient return via tree fall. This increased rate of return will substantially alter forest floor nutrient content and availability, especially with regard to calcium and nitrogen.

  12. 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

  13. Testing remote sensing estimates of bark beetle induced mortality in lodgepole pine and Engelmann spruce with ground data

    NASA Astrophysics Data System (ADS)

    King, A.; Ewers, B. E.; Sivanpillai, R.; Pendall, E.

    2012-12-01

    Bark beetles have caused widespread regional mortality in both lodgepole and Engelmann spruce forests across western North America, and while studies have addressed the impact on water partitioning caused by the mountain pine beetle, spruce beetle which often occur at high elevations with larger snowpack might have a disproportional impact. Beetle caused mortality can have significant effects on the hydrology of a watershed and therefore needs to be considered when evaluating increased runoff. The objective of this project was to generate maps showing beetle caused mortality for lodgepole pine and spruce fir forests that capture changes to the landscape to improve hydrologic models. Our study area in southeast Wyoming covered an area of approximately 2 by 4 km from 2700 to 2800m elevation range. High spatial resolution (0.5m) aerial imagery acquired by the Airborne Environmental Research Observational Camera (AEROCam) in fall 2011, provided by the Upper Midwest Aerospace Consortium (UMAC), was manually classified into four conifer thematic classes: live and dead lodgepole pine, and live and dead spruce/fir. The classified high resolution image was then verified by tree surveys conducted July-September, 2012 documenting species, tree diameter at breast height (dbh), and the stage of beetle infestation for each tree. After verification the high resolution aerial images were used to train and evaluate the accuracy of a supervised classification of a Landsat 5 Thematic Mapper image from the same time period and area. The preliminary results of a supervised classification show that map accuracy was 57%, 77%, 44%, and 83% for lodgepole live and dead, and spruce/fir live and dead respectively. The highest commission error, 24%, was for dead lodgepole pine being falsely labeled dead spruce/fir. The second highest commission error, 22%, was for live spruce/fir falsely labeled dead spruce/fir. The results indicate high spectral overlap between dead spruce/fir and dead

  14. Forest Ecosystem respiration estimated from eddy covariance and chamber measurements under high turbulence and substantial tree mortality from bark beetles

    USGS Publications Warehouse

    Speckman, Heather N.; Frank, John M.; Bradford, John B.; Miles, Brianna L.; Massman, William J.; Parton, William J.; Ryan, Michael G.

    2015-01-01

    Eddy covariance nighttime fluxes are uncertain due to potential measurement biases. Many studies report eddy covariance nighttime flux lower than flux from extrapolated chamber measurements, despite corrections for low turbulence. We compared eddy covariance and chamber estimates of ecosystem respiration at the GLEES Ameriflux site over seven growing seasons under high turbulence (summer night mean friction velocity (u*) = 0.7 m s−1), during which bark beetles killed or infested 85% of the aboveground respiring biomass. Chamber-based estimates of ecosystem respiration during the growth season, developed from foliage, wood and soil CO2 efflux measurements, declined 35% after 85% of the forest basal area had been killed or impaired by bark beetles (from 7.1 ±0.22 μmol m−2 s−1 in 2005 to 4.6 ±0.16 μmol m−2 s−1 in 2011). Soil efflux remained at ~3.3 μmol m−2 s−1 throughout the mortality, while the loss of live wood and foliage and their respiration drove the decline of the chamber estimate. Eddy covariance estimates of fluxes at night remained constant over the same period, ~3.0 μmol m−2 s−1 for both 2005 (intact forest) and 2011 (85% basal area killed or impaired). Eddy covariance fluxes were lower than chamber estimates of ecosystem respiration (60% lower in 2005, and 32% in 2011), but the mean night estimates from the two techniques were correlated within a year (r2 from 0.18-0.60). The difference between the two techniques was not the result of inadequate turbulence, because the results were robust to a u* filter of > 0.7 m s−1. The decline in the average seasonal difference between the two techniques was strongly correlated with overstory leaf area (r2=0.92). The discrepancy between methods of respiration estimation should be resolved to have confidence in ecosystem carbon flux estimates.

  15. The great spruce bark beetle (Dendroctonus micans Kug.) (Coleoptera: Scolytidae) in Lithuania: occurrence, phenology, morphology and communities of associated fungi.

    PubMed

    Menkis, A; Lynikienė, J; Marčiulynas, A; Gedminas, A; Povilaitienė, A

    2016-11-22

    We studied the occurrence, morphology and phenology of Dendroctonus micans in Lithuania and the fungi associated with the beetle at different developmental stages. The occurrence of D. micans was assessed in 19 seed orchards (at least 40 years old) of Picea abies (L. Karst.) situated in different parts of the country. Bark beetle phenology was studied in two sites: a seed orchard of P. abies and a plantation of Picea pungens (Engelm.). D. micans morphology was assessed under the dissection microscope using individuals at different developmental stages that were sampled during phenology observations. Communities of fungi associated with D. micans were studied using both fungal culturing methods and direct high-throughput sequencing from D. micans. Results showed that the incidence D. micans was relatively rare and D. micans was mainly detected in central and eastern Lithuania. The life cycle included the following stages: adult, egg, I-V developmental stage larvae and pupa. However, development of D. micans was quicker and its nests larger under the bark of P. pungens than of P. abies, indicating the effect of the host species. Fungal culturing and direct high-throughput sequencing revealed that D. micans associated fungi communities were species rich and dominated by yeasts from a class Saccharomycetes. In total, 319 fungal taxa were sequenced, among which Peterozyma toletana (37.5% of all fungal sequences), Yamadazyma scolyti (30.0%) and Kuraishia capsulate (17.7%) were the most common. Plant pathogens and blue stain fungi were also detected suggesting their potentially negative effects to both tree health and timber quality.

  16. Field response of Ips paraconfusus, Dendroctonus brevicomis, and their predators to 2-methyl-3-buten-2-ol, a novel alcohol emitted by ponderosa pine.

    PubMed

    Gray, Dennis W

    2002-08-01

    Methylbutenol (MBO) is a major component of the aggregation pheromone of the European spruce beetle Ips typographus and also has been found to be emitted in large amounts by several species of pine native to western North America. This study investigates the influence this signal may have on the behavior of North American bark beetles and examines whether MBO functions as a defensive compound for emitting pines. The response of two North American bark beetles (Ips paraconfusus and Dendroctonus brevicomis) and their predaceous beetles (Trogositidae and Cleridae) to MBO, pheromone, and monoterpenes in varying release rates was investigated in the field using Lindgren funnel traps. MBO exhibited no repellent properties when tested alone, nor did MBO appear to have any effect on the aggregation response of these bark beetles and their predators to their pheromones. These results provide no support for a defensive function of MBO.

  17. The pheromone frontalin and its dual function in the invasive bark beetle Dendroctonus valens.

    PubMed

    Liu, Zhudong; Xu, Bingbing; Miao, Zhenwang; Sun, Jianghua

    2013-07-01

    The red turpentine beetle, Dendroctonus valens LeConte, is one of the most destructive invasive forest pests in China, having killed more than 6 million pines since its first outbreak in 1999. Little is known about D. valens pheromone biology and no aggregation pheromone has yet been identified. Analysis by gas chromatograph/mass spectrometer of volatiles collected from live beetles in China showed that female beetles produce frontalin and males do not. Olfactory assays in the laboratory showed that males were attracted to frontalin at a wide range of concentrations, whereas females were attracted to it at a narrow range of concentrations. In field trials, 3-carene, a monoterpene kairomone from a pine tree selected to host the beetles attracted both sexes, and when frontalin was added, the total number of beetles captured increased by almost 200%. However, increasing concentrations of frontalin significantly decreased the percentage of female beetles trapped. These results suggest a new role of frontalin as an aggregation pheromone in addition to a female-produced sex pheromone, which was previously shown in a North American population. The dual functions of the pheromone frontalin produced by D. valens females, as well as its ecological significance for overcoming host resistance, are discussed.

  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.

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

    PubMed Central

    Lachowsky, Leanna E; Reid, Mary L

    2014-01-01

    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. PMID:25400320

  1. Attraction of southern pine engravers and associated bark beetles (Coleoptera: Scolytidae) to ipsenol, ipsdienol, and lanierone in southeastern United States.

    PubMed

    Miller, D R; Asaro, C; Berisford, C W

    2005-12-01

    We determined the response of the small southern pine engraver, Ips avulsus (Eichhoff); eastern fivespined ips, Ips grandicollis (Eichhoff); sixspined ips, Ips calligraphus (Germar); and pine engraver, Ips pini (Say) to the pheromones (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone in the southeastern United States. Catches of I. avulsus and I. grandicollis to baited multiple-funnel traps were increased by (+/-)-ipsenol and (+/-)-ipsdienol in Florida, Georgia, Louisiana, and North Carolina. In all four localities, the highest numbers of I. avulsus were caught in traps baited with the combination of (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone. In Florida, the highest numbers of I. grandicollis were captured in traps baited with the combination of (+/-)-ipsenol and (+/-)-ipsdienol (with or without lanierone). In the remaining three localities, the largest catches of I. grandicollis occurred in traps baited with (+/-)-ipsenol alone or the combination of (+/-)-ipsenol and (+/-)-ipsdienol (with or without lanierone). (+/-)-Ipsdienol was the only consistent attractant for I. calligraphus and I. pini. Attraction of I. pini in North Carolina to (+/-)-ipsdienol-baited traps was synergized by lanierone but interrupted with (+/-)-ipsenol. The interruptive effect of (+/-)-ipsenol on attraction of I. pini to (+/-)-ipsdienol was negated by lanierone. (+/-)-Ipsdienol was attractive to black turpentine beetle, Dendroctonus terebrans (Olivier), in Florida but not North Carolina, whereas (+/-)-ipsdienol was attractive to I. calligraphus in Louisiana, Georgia, and Florida. Both (+/-)-ipsenol and (+/-)-ipsdienol affected catches of Gnathotrichus materiarus (Fitch) in North Carolina. Trap catches of Hylurgops rugipennis pinifex (Fitch), Hylastes salebrosus Eichhoff, and Hylastes tenuis Eichhoff were unaffected by the pheromone treatments. The combination of (+/-)-ipsenol, (+/-)-ipsdienol, and lanierone may be a cost-effective general lure for I. avulsus, I. grandicollis, and I. pini.

  2. The Impact of Trap Type and Design Features on Survey and Detection of Bark and Woodboring Beetles and Their Associates: A Review and Meta-Analysis.

    PubMed

    Allison, Jeremy D; Redak, Richard A

    2017-01-31

    A large literature on the survey and detection of forest Coleoptera and their associates exists. Identification of patterns in the effect of trap types and design features among guilds and families of forest insects would facilitate the optimization and development of intercept traps for use in management programs. We reviewed the literature on trapping bark and woodboring beetles and their associates and conducted meta-analyses to examine patterns in effects across guilds and families; we observed the following general patterns: (a) Panel traps were superior to multiple-funnel traps, (b) bark beetles and woodborers were captured in higher numbers in traps treated with a surface treatment to make them slippery than untreated traps,

  3. 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

  4. Overshoot in Leaf Development of Ponderosa Pine in Wet Years Leads to Bark Beetle Outbreaks on Fine-Textured Soils in Drier Years

    NASA Astrophysics Data System (ADS)

    Peterman, W. L.; Waring, R. H.

    2014-12-01

    Frequent outbreaks of insects and diseases have been recorded in forests of western North America during the past few decades, but the distribution of these outbreaks has not been uniform. In some cases, recent climatic variations along with the age and density of forests may explain some spatial variation. Forest managers and policy makers would benefit if areas prone to disturbance could be recognized so that mitigating actions could be taken. In this paper, we used two ponderosa pine-dominated sites in western Montana, U.S.A. to apply a modelling approach that couples information from remote sensing, soil surveys, and local weather stations to assess where bark beetle outbreaks might first occur and why. There was a slight downward trend in precipitation for both sites over the period between 1998 and 2010, and, interannual variability was high. Some years showed large increases followed by sharp decreases. Both sites had similar topography and fire histories, but bark beetle activity occurred earlier and more severely on one site than the other. The initial canopy density of the two sites was also similar, with leaf area indices derived via Landsat imagery ranging between 1.6- 2.0 m2 m-2. We wondered if the difference in bark beetle activity might be related to soils that were fine-textured at site I and coarse-textured at site II. We applied a process-based stand growth model (3-PG) to analyze the data and evaluate the hypotheses.

  5. Another Asian ambrosia bark beetle, Xyleborinus artestriatus (Eichhoff) (Coleoptera: Curculionidae: Scolytinae), found in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Xyleborinus artestriatus (Eichhoff), an ambrosia beetle native to Asia, is reported for the first time in North America based on specimens from Georgia and Texas. This is the twenty-fourth species of exotic Xyleborina documented in North America. North American distributional records, key identifica...

  6. 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

  7. Metal fate and partitioning in soils under bark beetle-killed trees.

    PubMed

    Bearup, Lindsay A; Mikkelson, Kristin M; Wiley, Joseph F; Navarre-Sitchler, Alexis K; Maxwell, Reed M; Sharp, Jonathan O; McCray, John E

    2014-10-15

    Recent mountain pine beetle infestation in the Rocky Mountains of North America has killed an unprecedented acreage of pine forest, creating an opportunity to observe an active re-equilibration in response to widespread land cover perturbation. This work investigates metal mobility in beetle-impacted forests using parallel rainwater and acid leaches to estimate solid-liquid partitioning coefficients and a complete sequential extraction procedure to determine how metals are fractionated in soils under trees experiencing different phases of mortality. Geochemical model simulations analyzed in consideration with experimental data provide additional insight into the mechanisms controlling metal complexation. Metal and base-cation mobility consistently increased in soils under beetle-attacked trees relative to soil under healthy trees. Mobility increases were more pronounced on south facing slopes and more strongly correlated to pH under attacked trees than under healthy trees. Similarly, soil moisture was significantly higher under dead trees, related to the loss of transpiration and interception. Zinc and cadmium content increased in soils under dead trees relative to living trees. Cadmium increases occurred predominantly in the exchangeable fraction, indicating increased mobilization potential. Relative increases of zinc were greatest in the organic fraction, the only fraction where increases in copper were observed. Model results reveal that increased organic complexation, not changes in pH or base cation concentrations, can explain the observed differences in metal partitioning for zinc, nickel, cadmium, and copper. Predicted concentrations would be unlikely to impair human health or plant growth at these sites; however, higher exchangeable metals under beetle-killed trees relative to healthy trees suggest a possible decline in riverine ecosystem health and water quality in areas already approaching criteria limits and drinking water standards. Impairment of water

  8. Terpenes tell different tales at different scales: glimpses into the Chemical Ecology of conifer - bark beetle - microbial interactions.

    PubMed

    Raffa, Kenneth F

    2014-01-01

    Chemical signaling mediates nearly all aspects of species interactions. Our knowledge of these signals has progressed dramatically, and now includes good characterizations of the bioactivities, modes of action, biosynthesis, and genetic programming of numerous compounds affecting a wide range of species. A major challenge now is to integrate this information so as to better understand actual selective pressures under natural conditions, make meaningful predictions about how organisms and ecosystems will respond to a changing environment, and provide useful guidance to managers who must contend with difficult trade-offs among competing socioeconomic values. One approach is to place stronger emphasis on cross-scale interactions, an understanding of which can help us better connect pattern with process, and improve our ability to make mechanistically grounded predictions over large areas and time frames. The opportunity to achieve such progress has been heightened by the rapid development of new scientific and technological tools. There are significant difficulties, however: Attempts to extend arrays of lower-scale processes into higher scale functioning can generate overly diffuse patterns. Conversely, attempts to infer process from pattern can miss critically important lower-scale drivers in systems where their biological and statistical significance is negated after critical thresholds are breached. Chemical signaling in bark beetle - conifer interactions has been explored for several decades, including by the two pioneers after whom this award is named. The strong knowledge base developed by many researchers, the importance of bark beetles in ecosystem functioning, and the socioeconomic challenges they pose, establish these insects as an ideal model for studying chemical signaling within a cross-scale context. This report describes our recent work at three levels of scale: interactions of bacteria with host plant compounds and symbiotic fungi (tree level

  9. Mutual interactions between an invasive bark beetle and its associated fungi.

    PubMed

    Wang, B; Salcedo, C; Lu, M; Sun, J

    2012-02-01

    Interactions between invasive insects and their fungal associates have important effects on the behavior, reproductive success, population dynamics and evolution of the organisms involved. The red turpentine beetle (RTB), Dendroctonus valens LeConte (Coleoptera: Scolytinae), an invasive forest pest in China, is closely associated with fungi. By carrying fungi on specialized structures in the exoskeleton, RTB inoculates fungi in the phloem of pines (when females dig galleries for egg laying and when males join them for mating). After eggs hatch, larvae gregariously feed on the phloem colonized by the fungi. We examined the effects of five isolates of RTB associated fungi (two from North America, Leptographium terebrantis and L. procerum, and three from China, Ophiostoma minus, L. sinoprocerum and L. procerum) on larval feeding activity, development and mortality. We also studied the effects of volatile chemicals produced in the beetle hindgut on fungal growth. Ophiostoma minus impaired feeding activity and reduced weight in RTB larvae. Leptographium sinoprocerum, L. terebrantis and L. procerum did not dramatically influence larval feeding and development compared to fungi-free controls. Larval mortality was not influenced by any of the tested fungi. Hindgut volatiles of RTB larvae, verbenol, myrtenol and myrtenal, inhibited growth rate of all the fungi. Our results not only show that D. valens associated fungus, O. minus, can be detrimental to its larvae; but, most importantly, they also show that these notorious beetles have an outstanding adaptive response evidenced by the ability to produce volatiles that inhibit growth of harmful fungus.

  10. Complex interactions among host pines and fungi vectored by an invasive bark beetle.

    PubMed

    Lu, Min; Wingfield, Michael J; Gillette, Nancy E; Mori, Sylvia R; Sun, Jiang-Hua

    2010-08-01

    *Recent studies have investigated the relationships between pairs or groups of exotic species to illustrate invasive mechanisms, but most have focused on interactions at a single trophic level. *Here, we conducted pathogenicity tests, analyses of host volatiles and fungal growth tests to elucidate an intricate network of interactions between the host tree, the invasive red turpentine beetle and its fungal associates. *Seedlings inoculated with two strains of Leptographium procerum isolated from Dendroctonus valens in China had significantly longer lesions and higher mortality rates than seedlings inoculated with other fungal isolates. These two strains of L. procerum were significantly more tolerant of 3-carene than all other fungi isolated there, and the infection of Chinese pine (Pinus tabuliformis) seedlings by these two strains enhanced the production and release of 3-carene, the main attractant for D. valens, by the seedlings. *Our results raise the possibility that interactions among the fungal associates of D. valens and their pine hosts in China may confer advantages to these strains of L. procerum and, by extension, to the beetles themselves. These interactions may therefore enhance invasion by the beetle-fungal complex.

  11. Influence of Terrain and Land Cover on the Isotopic Composition of Seasonal Snowpack in Rocky Mountain Headwater Catchments Affected by Bark Beetle Induced Tree Mortality

    NASA Astrophysics Data System (ADS)

    Kipnis, E. L.; Murphy, M.; Klatt, A. L.; Miller, S. N.; Williams, D. G.

    2015-12-01

    Session H103: The Hydrology-Vegetation-Climate Nexus: Identifying Process Interactions and Environmental Shifts in Mountain Catchments Influence of Terrain and Land Cover on the Isotopic Composition of Seasonal Snowpack in Rocky Mountain Headwater Catchments Affected by Bark Beetle Induced Tree Mortality Evan L Kipnis, Melanie A Murphey, Alan Klatt, Scott N Miller, David G Williams Snowpack accumulation and ablation remain difficult to estimate in forested headwater catchments. How physical terrain and forest cover separately and interactively influence spatial patterns of snow accumulation and ablation largely shapes the hydrologic response to land cover disturbances. Analysis of water isotopes in snowpack provides a powerful tool for examining integrated effects of water vapor exchange, selective redistribution, and melt. Snow water equivalence (SWE), δ2H, δ18O and deuterium excess (D-excess) of snowpack were examined throughout winter 2013-2014 across two headwater catchments impacted by bark beetle induced tree mortality. A USGS 10m DEM and a derived land cover product from 1m NAIP imagery were used to examine the effects of terrain features (e.g., elevation, slope, aspect) and canopy disturbance (e.g., live, bark-beetle killed) as predictors of D-excess, an expression of kinetic isotope effects, in snowpack. A weighting of Akaike's Information Criterion (AIC) values from multiple spatially lagged regression models describing D-excess variation for peak snowpack revealed strong effects of elevation and canopy mortality, and weaker, but significant effects of aspect and slope. Snowpack D-excess was lower in beetle-killed canopy patches compared to live green canopy patches, and at lower compared to high elevation locations, suggesting that integrated isotopic effects of vapor exchange, vertical advection of melted snow, and selective accumulation and redistribution varied systematically across the two catchments. The observed patterns illustrate the potential

  12. Distinguishing Bark Beetle-infested Vegetation by Tree Species Types and Stress Levels using Landsat Data

    NASA Astrophysics Data System (ADS)

    Sivanpillai, R.; Ewers, B. E.; Speckman, H. N.; Miller, S. N.

    2015-12-01

    In the Western United States, more than 3 million hectares of lodgepole pine forests have been impacted by the Mountain pine beetle outbreak, while another 166,000 hectares of spruce-fir forests have been attacked by Spruce beetle. Following the beetle attack, the trees lose their hydraulic conductivity thus altering their carbon and water fluxes. These trees go through various stages of stress until mortality, described by color changes in their needles prior to losing them. Modeling the impact of these vegetation types require thematically precise land cover data that distinguishes lodgepole pine and spruce-fir forests along with the stage of impact since the ecosystem fluxes are different for these two systems. However, the national and regional-scale land cover datasets derived from remotely sensed data do not have this required thematic precision. We evaluated the feasibility of multispectral data collected by Landsat 8 to distinguish lodgepole pine and spruce fir, and subsequently model the different stages of attack using field data collected in Medicine Bow National Forest (Wyoming, USA). Operational Land Imager, onboard Landsat 8 has more spectral bands and higher radiometric resolution (12 bit) in comparison to sensors onboard earlier Landsat missions which could improve the ability to distinguish these vegetation types and their stress conditions. In addition to these characteristics, its repeat coverage, rigorous radiometric calibration, wide swath width, and no-cost data provide unique advantages to Landsat data for mapping large geographic areas. Initial results from this study highlight the importance of SWIR bands for distinguishing different levels of stress, and the need for ancillary data for distinguishing species types. Insights gained from this study could lead to the generation of land cover maps with higher thematic precision, and improve the ability to model various ecosystem processes as a result of these infestations.

  13. Hydrological effects of forest transpiration loss in bark beetle-impacted watersheds

    USGS Publications Warehouse

    Bearup, Lindsay A.; Maxwell, Reed M.; Clow, David W.; McCray, John E.

    2014-01-01

    The recent climate-exacerbated mountain pine beetle infestation in the Rocky Mountains of North America has resulted in tree death that is unprecedented in recorded history. The spatial and temporal heterogeneity inherent in insect infestation creates a complex and often unpredictable watershed response, influencing the primary storage and flow components of the hydrologic cycle. Despite the increased vulnerability of forested ecosystems under changing climate1, watershed-scale implications of interception, ground evaporation, and transpiration changes remain relatively unknown, with conflicting reports of streamflow perturbations across regions. Here, contributions to streamflow are analysed through time and space to investigate the potential for increased groundwater inputs resulting from hydrologic change after infestation. Results demonstrate that fractional late-summer groundwater contributions from impacted watersheds are 30 ± 15% greater after infestation and when compared with a neighbouring watershed that experienced earlier and less-severe attack, albeit uncertainty propagations through time and space are considerable. Water budget analysis confirms that transpiration loss resulting from beetle kill can account for the relative increase in groundwater contributions to streams, often considered the sustainable flow fraction and critical to mountain water supplies and ecosystems.

  14. Hydrological effects of forest transpiration loss in bark beetle-impacted watersheds

    NASA Astrophysics Data System (ADS)

    Bearup, Lindsay A.; Maxwell, Reed M.; Clow, David W.; McCray, John E.

    2014-06-01

    The recent climate-exacerbated mountain pine beetle infestation in the Rocky Mountains of North America has resulted in tree death that is unprecedented in recorded history. The spatial and temporal heterogeneity inherent in insect infestation creates a complex and often unpredictable watershed response, influencing the primary storage and flow components of the hydrologic cycle. Despite the increased vulnerability of forested ecosystems under changing climate, watershed-scale implications of interception, ground evaporation, and transpiration changes remain relatively unknown, with conflicting reports of streamflow perturbations across regions. Here, contributions to streamflow are analysed through time and space to investigate the potential for increased groundwater inputs resulting from hydrologic change after infestation. Results demonstrate that fractional late-summer groundwater contributions from impacted watersheds are 30 +/- 15% greater after infestation and when compared with a neighbouring watershed that experienced earlier and less-severe attack, albeit uncertainty propagations through time and space are considerable. Water budget analysis confirms that transpiration loss resulting from beetle kill can account for the relative increase in groundwater contributions to streams, often considered the sustainable flow fraction and critical to mountain water supplies and ecosystems.

  15. Systemic effects of Heterobasidion annosum on ferulic acid glucoside and lignin of presymptomatic ponderosa pine phloem, and potential effects on bark-beetle-associated fungi.

    PubMed

    Bonello, Pierluigi; Storer, Andrew J; Gordon, Thomas R; Wood, David L; Heller, Werner

    2003-05-01

    Concentrations of soluble phenolics and lignin in the phloem of ponderosa pines inoculated with the pathogen Heterobasidion annosum were assessed over a period of 2 years in a 35-year-old plantation in northern California, USA. The major effect of the pathogen on phloem-soluble phenolics consisted of a significant accumulation of ferulic acid glucoside: 503 +/- 27 microg/g fresh weight (FW), compared with 366 +/- 26 microg/g FW for mock-treated and 386 +/- 27 microg/g FW for control trees. Lignin content was negatively correlated with ferulic acid glucoside concentration, and there was an indication of lignin reduction in the cell walls of inoculated trees. Lignin had a negative effect on the in vitro growth of two common bark beetle fungal associates. Ceratocystiopsis brevicomi and Ophiostoma minus. For this reason it, is hypothesized that lower lignification may facilitate the growth of beetle-associated fungi, resulting in greater susceptibility of the presymptomatic host to bark beetle colonization.

  16. Mattesia weiseri sp. nov., a new neogregarine (Apicomplexa: Lipotrophidae) pathogen of the great spruce bark beetle, Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae).

    PubMed

    Yaman, Mustafa; Radek, Renate

    2015-08-01

    A new neogregarine pathogen of the great spruce bark beetle, Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae), is described based on light microscopy and ultrastructural characteristics. The pathogen infects the fat body and the hemolymph of the beetle. The infection was nonsynchronous so that different developmental stages could be observed simultaneously in the hemolymph. All life stages from sporozoite to oocyst of the pathogen including micronuclear and macronuclear merozoites were detected. The sporozoites measured about 8.7 × 1.9 μm and trophozoites, 11.9 × 3.3 μm. Micronuclear merozoites seen in the hemolymph were motile, elongate, slightly broader at the anterior pole, and measured 18.4 × 2.0 μm. Macronuclear merozoites had a size of ca. 16.4 × 2.3 μm. Gametogamy results in the formation of two paired oocysts within a gametocyst. The lemon-shaped oocyst measured 10.9 × 6.1 μm and had a very thick wall (375-450 nm). All morphological and ultrastructural characteristics of the life cycle stages indicate that the described neogregarine in D. micans is clearly different from known Mattesia species infecting bark beetles, and from any other described Mattesia spp. Therefore, we create a new species, Mattesia weiseri sp. nov.

  17. Contributions by Host Trees and Insect Activity to Bacterial Communities in Dendroctonus valens (Coleoptera: Curculionidae) Galleries, and Their High Overlap With Other Microbial Assemblages of Bark Beetles.

    PubMed

    Mason, Charles J; Hanshew, Alissa S; Raffa, Kenneth F

    2016-04-01

    Bark beetles are associated with a diversity of symbiotic microbiota that can mediate interactions with their host plants. Dendroctonus valens LeConte is a widely distributed bark beetle in North and Central America, and initiates solitary attacks on several species of Pinus in the Great Lakes region. In this study, we aimed to further characterize the bacterial community associated with D. valens feeding galleries using next-generation sequencing, and the possible contributions of both tree-resident and insect-associated bacteria to these consortia. We found that D. valens galleries harbor a diversity of microbial associates. Many of these associates were classified into a few taxonomic groups, of which Gammaproteobacteria were the most abundant class. Of the Gammaproteobacteria detected, many formed clades with 16S-rRNA sequences of bacteria previously associated with D. valens Many of the bacteria sequences detected in the galleries were similar to bacteria that function in detoxification, kairomone metabolism, and nitrogen fixation and cycling. The abundance of bacteria in galleries were 7× and 44× higher than in the surrounding uninfested tissues, and that were not attacked by D. valens, respectively. This suggests that the bacteria present in beetle galleries are largely introduced by D. valens and proliferate in this environment.

  18. Host suitability analysis of the bark beetle Scolytus amygdali (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Zeiri, A; Ahmed, M Z; Braham, M; Qiu, B-L

    2015-08-01

    Scolytus amygdali is a polyphagous insect pest that feeds on fruit trees and forest trees. Our study assessed the host preference and reproductive potential of S. amygdali on four tree species: almond (Prunus dulcis), apricot (Prunus armeniaca), peach (Prunus persica), and plum (Prunus domestica). Females of S. amygdali produced maternal galleries that were longer on peach than the other three trees, and female fecundity was highest on peach. Females with longer maternal galleries produced more eggs, indicating a positive correlation between maternal gallery length and female fertility. The under-bark development time of S. amygdali is significantly shorter on plum (45 days) and almond (56 days) than on apricot (65 days) and peach (64 days). Despite this longer development time on peach, our results still suggest that, of the four types of tree tested, peach is the most preferred host for S. amygdali.

  19. Flying the nest: male dispersal and multiple paternity enables extrafamilial matings for the invasive bark beetle Dendroctonus micans.

    PubMed

    Fraser, C I; Brahy, O; Mardulyn, P; Dohet, L; Mayer, F; Grégoire, J-C

    2014-10-01

    There is an evolutionary trade-off between the resources that a species invests in dispersal versus those invested in reproduction. For many insects, reproductive success in patchily-distributed species can be improved by sibling-mating. In many cases, such strategies correspond to sexual dimorphism, with males-whose reproductive activities can take place without dispersal-investing less energy in development of dispersive resources such as large body size and wings. This dimorphism is particularly likely when males have little or no chance of mating outside their place of birth, such as when sperm competition precludes successful fertilisation in females that have already mated. The economically important bark beetle pest species Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae) has been considered to be exclusively sibling-mating, with 90% of females having already mated with their brothers by emergence. The species does not, however, show strong sexual dimorphism; males closely resemble females, and have been observed flying through forests. We hypothesised that this lack of sexual dimorphism indicates that male D. micans are able to mate with unrelated females, and to sire some or all of their offspring, permitting extrafamilial reproduction. Using novel microsatellite markers, we carried out cross-breeding laboratory experiments and conducted paternity analyses of resulting offspring. Our results demonstrate that a second mating with a less-related male can indeed lead to some offspring being sired by the latecomer, but that most are sired by the first, sibling male. We discuss these findings in the context of sperm competition versus possible outbreeding depression.

  20. Flying the nest: male dispersal and multiple paternity enables extrafamilial matings for the invasive bark beetle Dendroctonus micans

    PubMed Central

    Fraser, C I; Brahy, O; Mardulyn, P; Dohet, L; Mayer, F; Grégoire, J-C

    2014-01-01

    There is an evolutionary trade-off between the resources that a species invests in dispersal versus those invested in reproduction. For many insects, reproductive success in patchily-distributed species can be improved by sibling-mating. In many cases, such strategies correspond to sexual dimorphism, with males–whose reproductive activities can take place without dispersal–investing less energy in development of dispersive resources such as large body size and wings. This dimorphism is particularly likely when males have little or no chance of mating outside their place of birth, such as when sperm competition precludes successful fertilisation in females that have already mated. The economically important bark beetle pest species Dendroctonus micans (Coleoptera: Curculionidae, Scolytinae) has been considered to be exclusively sibling-mating, with 90% of females having already mated with their brothers by emergence. The species does not, however, show strong sexual dimorphism; males closely resemble females, and have been observed flying through forests. We hypothesised that this lack of sexual dimorphism indicates that male D. micans are able to mate with unrelated females, and to sire some or all of their offspring, permitting extrafamilial reproduction. Using novel microsatellite markers, we carried out cross-breeding laboratory experiments and conducted paternity analyses of resulting offspring. Our results demonstrate that a second mating with a less-related male can indeed lead to some offspring being sired by the latecomer, but that most are sired by the first, sibling male. We discuss these findings in the context of sperm competition versus possible outbreeding depression. PMID:24736784

  1. Altered Carbohydrates Allocation by Associated Bacteria-fungi Interactions in a Bark Beetle-microbe Symbiosis.

    PubMed

    Zhou, Fangyuan; Lou, Qiaozhe; Wang, Bo; Xu, Letian; Cheng, Chihang; Lu, Min; Sun, Jianghua

    2016-02-03

    Insect-microbe interaction is a key area of research in multiplayer symbiosis, yet little is known about the role of microbe-microbe interactions in insect-microbe symbioses. The red turpentine beetle (RTB) has destroyed millions of healthy pines in China and forms context-dependent relationships with associated fungi. The adult-associated fungus Leptographium procerum have played key roles in RTB colonization. However, common fungal associates (L. procerum and Ophiostoma minus) with RTB larvae compete for carbohydrates. Here, we report that dominant bacteria associated with RTB larvae buffer the competition by inhibiting the growth and D-glucose consumption of O. minus. However, they didn't inhibit the growth of L. procerum and forced this fungus to consume D-pinitol before consuming D-glucose, even though D-glucose was available and a better carbon source not only for L. procerum but also for RTB larvae and associated bacteria. This suggests the most frequently isolated bacteria associated with RTB larvae could affect fungal growth and the sequence of carbohydrate consumption. Thus, this regulates carbohydrate allocation in the RTB larva-microbe community, which may in turn benefit RTB larvae development. We also discuss the mechanism of carbohydrate allocation in the RTB larva-microbe community, and its potential contribution to the maintenance of a symbiotic community.

  2. Altered Carbohydrates Allocation by Associated Bacteria-fungi Interactions in a Bark Beetle-microbe Symbiosis

    PubMed Central

    Zhou, Fangyuan; Lou, Qiaozhe; Wang, Bo; Xu, Letian; Cheng, Chihang; Lu, Min; Sun, Jianghua

    2016-01-01

    Insect-microbe interaction is a key area of research in multiplayer symbiosis, yet little is known about the role of microbe-microbe interactions in insect-microbe symbioses. The red turpentine beetle (RTB) has destroyed millions of healthy pines in China and forms context-dependent relationships with associated fungi. The adult-associated fungus Leptographium procerum have played key roles in RTB colonization. However, common fungal associates (L. procerum and Ophiostoma minus) with RTB larvae compete for carbohydrates. Here, we report that dominant bacteria associated with RTB larvae buffer the competition by inhibiting the growth and D-glucose consumption of O. minus. However, they didn’t inhibit the growth of L. procerum and forced this fungus to consume D-pinitol before consuming D-glucose, even though D-glucose was available and a better carbon source not only for L. procerum but also for RTB larvae and associated bacteria. This suggests the most frequently isolated bacteria associated with RTB larvae could affect fungal growth and the sequence of carbohydrate consumption. Thus, this regulates carbohydrate allocation in the RTB larva-microbe community, which may in turn benefit RTB larvae development. We also discuss the mechanism of carbohydrate allocation in the RTB larva-microbe community, and its potential contribution to the maintenance of a symbiotic community. PMID:26839264

  3. Connecting Increased Groundwater Contributions to Transpiration Losses in Bark Beetle-Infested Watersheds

    NASA Astrophysics Data System (ADS)

    Bearup, L. A.; Maxwell, R. M.; Penn, C. A.; Clow, D. W.; McCray, J. E.

    2013-12-01

    Recent climate-exacerbated infestation of the mountain pine beetle (MPB) in the Rocky Mountain west has resulted in unprecedented tree death across the region. The spatial and temporal heterogeneity of the epidemic creates a complex and often inconsistent watershed response, impacting the primary storage and flow components of the hydrologic cycle. Within two years, trees have ceased to transpire and the subsequent loss of canopy cover results in increased precipitation and energy fluxes to the ground surface, causing changes in soil moisture dynamics and snowmelt processes. While snowmelt is of particular interest for water supply from these important mountain watersheds, the low flow season in late summer and fall may have important implications for water quality and riverine ecology. In this work, we use chemical hydrograph separation and a particle tracking model to temporally and spatially investigate alterations to stream flow generation processes from the loss of transpiration at the watershed scale. Specifically, we examine the potential for increased groundwater contributions to stream flow during the late summer and early fall. Here we found that late summer baseflow stream contributions increase with increasing levels of infestation both spatially and temporally. Consistent with water budget analyses, we hypothesize that this increase is due to the loss of transpiration from tree mortality. Ultimately, this work moves toward a better quantitative understanding of the importance of transpiration at the watershed scale.

  4. Effects of bark beetle infestation on hydrology and land-energy feedbacks in mountain headwaters

    NASA Astrophysics Data System (ADS)

    Penn, C. A.; Maxwell, R. M.; Engdahl, N. B.; Clow, D. W.

    2013-12-01

    Infestation of mountain pine beetle (MPB) throughout the Rocky Mountain Region has caused substantial tree mortality in critical sub-alpine and montane zones. The potential changes in land-energy and water balances caused by MPB tree mortality are demonstrated through hillslope-scale integrated modeling and regional-scale atmospheric modeling using the ParFlow-CLM model for the headwaters of the Big Thompson watershed in Rocky Mountain National Park, Colo. ParFlow is a variably saturated, integrated groundwater and surface-water model that solves Richard's equation in 3D and routes overland flow with Manning's equation. Parflow is coupled with the Community Land Model (CLM) to incorporate land-surface processes and energy fluxes. The Big Thompson headwaters (358 km2) include sub-alpine and montane zones where forests are experiencing substantial tree mortality. The MPB infestation was documented in the watershed beginning in 1998 with many ecohydrological factors contributing to the rapid spread of infestation and tree mortality since 2007. In addition to vegetation information, data from multiple U.S. Geological Survey stream-gage and water-quality sites in the study area allow for comparisons between model output and observations. The ParFlow-CLM model of the Big Thompson headwaters uses a 0.01km2 grid-cell size with variable subsurface depth and is driven by distributed hourly meteorological forcing. Vegetation and associated land-cover changes related to MPB infestations are applied in the model through adjustments to parameters that reflect those found in forest ecology literature. Results at the hillslope-scale show significant changes in transpiration, snowfall, snowmelt, and the near-surface energy balance as a result of MPB tree mortality. Model simulations from MPB and non-MPB scenarios are being compared with observations of streamflow and analyzed for the magnitude of change in land-energy and water balances. This investigation supports regional water

  5. Impact of bark beetle calamity on soil moisture dynamics during floods and droughts in 2013 - case study of Rokytka Brook catchment, Šumava Mts., Czech Republic

    NASA Astrophysics Data System (ADS)

    Vlcek, Lukas; Kocum, Jan; Jansky, Bohumir; Sefrna, Ludek

    2014-05-01

    This paper describes the dynamics of soil moisture in the experimental catchment of Rokytka Brook, Otava River basin, Šumava National Park, Czech Republic. This area has a long-term problems with bark beetle which results predominantly in the spruce forest perdition. This phenomenon has resulted not only in a change of a vegetation composition, but also it has impacted the development of local land cover, soil moisture dynamics or the storage capacity of soils and the potential retention conditions within the basin . The experimental catchment, where the research was carried out, consists by 2/3 of terrestrial soil (Entic Podzol). The soil is covered by the dead forest (former spuce forest before bark beetle calamity) and by the beech forest (former spruce-beech forest). The rest of the basin consists of well-developed peatbogs that represents a typical example of a peatbog in Šumava Mts. In terms of vegetation, the area can be divided into a lower part consisting of healthy waterlogged spruce forest, the mountain pine covers the middle part and the upper part is covered mostly by the cotton grass. In the part where terrestrial soils predominate, measuring of soil pressures and temperatures at two depths (20 and 60 cm) at two sites (former spruce-beech and spruce forest) has been carried out since 2012. Due to the bark beetle calamity, the spruce forest has become withered and thus the vegetation cover has changed. Meteorological data (precipitation, air temperature, humidity) are collected by meteorological stations located within the basin or used from nearby stations (solar radiation, wind speed). The outflow from the experimental catchment is also measured. The aim of this paper is to simulate the dynamics of a soil moisture condition before bark beetle outbreak, to compare the differences and changes of a soil moisture and retention ability of a typical soil type in the case of a characteristic headwater catchment in Šumava Mts. For the simulation of a soil

  6. Net ecosystem exchange of carbon dioxide and evapotranspiration response of a high elevation Rocky Mountain (Wyoming, USA) forest to a bark beetle epidemic

    NASA Astrophysics Data System (ADS)

    Frank, J. M.; Massman, W. J.; Ewers, B. E.

    2011-12-01

    Bark beetle epidemics have caused major disturbance in the forests of western North America where significant tree mortality alters the balance of ecosystem photosynthesis, carbon balance, and water exchange. In this study we investigate the change in the growing-season light-response of net ecosystem exchange of carbon dioxide (NEE) and evapotranspiration (ET) in a high elevation Rocky Mountain forest over the three years preceding and three years following a bark beetle outbreak. The GLEES AmeriFlux site (southeastern Wyoming, USA) is located in a high elevation subalpine forest dominated by Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) and recently experienced an epidemic of spruce beetle (Dendroctonus rufipennis). The peak beetle outbreak occurred in 2008, and has impacted 35% of the stems and 90% of the basal area of Engelmann spruce, which accounts for 30% of the trees and 70% of the basal area of the forest. Two semi-empirical light response curves for eddy-covariance carbon flux were compared, with a logistic sigmoid performing better because of residual bias than a rectangular hyperbola (Michaelis-Menten) at estimating the quantum yield of photosynthesis. In the first two years after the peak beetle outbreak the original quantum yield of 0.015 mol mol-1 was reduced by 25%. By the third year it was reduced by a half, which was composed of declines of 45% in the ecosystem's responses to diffuse radiation and 60% to direct radiation. The light-saturated rate of photosynthesis decreased by 10% in the first two years post outbreak, and fell by 40% in the third year. After the peak outbreak, the cumulative NEE over the growing season was reduced by over a half from a sink of 185 gC m-2 to 80 gC m-2, and by the third year it was reduced to near zero, or carbon neutral. The change in the ET response to light was similar in all years after the peak outbreak where the slope of the response curve was decreased by 25%. This led to a

  7. 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.

  8. The Rocky Mountain Epidemic of Bark Beetles and Blue Stain Fungi Cause Cascading Effects on Coupled Water, C and N cycles

    NASA Astrophysics Data System (ADS)

    Ewers, B. E.; Pendall, E.; Norton, U.; Reed, D.; Franks, J.; Aston, T.; Whitehouse, F.; Barnard, H. R.; Brooks, P. D.; Angstmann, J.; Massman, W. J.; Williams, D. G.; Harpold, A. A.; Biederman, J.; Edburg, S. L.; Meddens, A. J.; Gochis, D. J.; Hicke, J. A.

    2010-12-01

    The ongoing epidemic of bark beetles and their associated xylem blocking blue-stain fungi is unprecedented in Rocky Mountain subalpine forests. As this epidemic continues, we seek to improve our predictive understanding of coupled water, C and N cycles by quantifying how these cycles may become uncoupled in response to the outbreak. Our specific questions are 1) how does the rapid drop in individual tree transpiration impact the temporal and spatial extent of evapotranspiration and 2) how does the subsequent increase in soil moisture and lower C inputs and N uptake impact soil C and N fluxes? We address these questions in two forest ecosystems using eddy covariance, sap flux, leaf gas exchange, plant hydraulic conductance, vegetation characteristics and soil trace gas measurements. We applied two sampling designs 1) subdivide the lodgepole pine forest spatially into varying degrees of bark beetle and blue stain infection and 2) follow the fluxes as the outbreak continues at a point in space encompassing the range of spatial variability in mortality. The first order impact of the bark beetle and blue stain fungi is dramatic in all tree species with a greater than 50% reduction in transpiration per tree within a month of infection. This change occurs even before the characteristic red tinge occurs in the needles or before the sapwood is stained blue. Leaf stomatal conductance declines more than either the biochemical or light harvesting components of photosynthesis immediately after infestation. The annual C sink at the spruce/fir forest has declined from -2.88 to -0.57 Mg C ha-1 yr-1 from 2006 to 2009. Annual evapotranspiration (ET) over the last five years at the spruce/fir forest now has an inverse relationship with precipitation because the last two years have seen a dramatic decrease (from 73 to 59 cm/year) in ET while precipitation has increased (from ~100 to 140 cm/year). Soil moisture in both forests has increased up to 100% within one growing season in

  9. Carbon isotopic composition of forest soil respiration in the decade following bark beetle and stem girdling disturbances in the Rocky Mountains.

    PubMed

    Maurer, Gregory E; Chan, Allison M; Trahan, Nicole A; Moore, David J P; Bowling, David R

    2016-07-01

    Bark beetle outbreaks are widespread in western North American forests, reducing primary productivity and transpiration, leading to forest mortality across large areas and altering ecosystem carbon cycling. Here the carbon isotope composition (δ(13) C) of soil respiration (δJ ) was monitored in the decade after disturbance for forests affected naturally by mountain pine beetle infestation and artificially by stem girdling. The seasonal mean δJ changed along both chronosequences. We found (a) enrichment of δJ relative to controls (<1 ‰) in near-surface soils in the first 2 years after disturbance; (b) depletion (1‰ or no change) during years 3-7; and (c) a second period of enrichment (1-2‰) in years 8-10. Results were consistent with isotopic patterns associated with the gradual death and decomposition of rhizosphere organisms, fine roots, conifer needles and woody roots and debris over the course of a decade after mortality. Finally, δJ was progressively more (13) C-depleted deeper in the soil than near the surface, while the bulk soil followed the well-established pattern of (13) C-enrichment at depth. Overall, differences in δJ between mortality classes (<1‰) and soil depths (<3‰) were smaller than variability within a class or depth over a season (up to 6‰).

  10. 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.

  11. Carbon and Nitrogen Levels across Forest Soil Communities Impacted by Bark Beetle and Wildfire Disturbance in Western Montana

    NASA Astrophysics Data System (ADS)

    Kim, E. S. M.; Ballantyne, A. P.; Cooper, L. A.; Hursh, A.

    2014-12-01

    Global climate change has had extensive impacts on the forest ecosystems of the western US, namely by causing increases in mountain pine beetle numbers and wildfires. Mountain pine beetles experience higher survival rates due to milder winters, allowing for greater frequency and severity of attacks and in turn causing more widespread pine tree mortality. Meanwhile, the arid conditions created by this temperature increase have been conducive to a surge in wildfires. Although many investigations have been carried out on the soil biogeochemistry in areas hit by one or the other, no study to our knowledge has explicitly researched the compound effects of these disturbances. This study examined soil levels of carbon (C) and nitrogen (N) as well as the C/N ratios of pine and fir soil communities that have been affected by both beetle and fire disturbance. Our results show that no significant differences were found in the C/N ratios in response to all modes of disturbance. However, significant C losses from the O horizon, but not the M horizon, were observed following wildfire. Similarly, losses in N from just the O horizon were observed, but these were not significant. In conclusion, fire resulted in marked declines in soil C, and forests impacted by beetle infestation and fire experienced C losses similar to fire alone.

  12. Augmenting forest inventory attributes with geometric optical modelling in support of regional susceptibility assessments to bark beetle infestations

    NASA Astrophysics Data System (ADS)

    Coggins, Sam B.; Coops, Nicholas C.; Hilker, Thomas; Wulder, Michael A.

    2013-04-01

    Assessment of the susceptibility of forests to mountain pine beetle (Dendroctonus ponderosae Hopkins) infestation is based upon an understanding of the characteristics that predispose the stands to attack. These assessments are typically derived from conventional forest inventory data; however, this information often represents only managed forest areas. It does not cover areas such as forest parks or conservation regions and is often not regularly updated resulting in an inability to assess forest susceptibility. To address these shortcomings, we demonstrate how a geometric optical model (GOM) can be applied to Landsat-5 Thematic Mapper (TM) imagery (30 m spatial resolution) to estimate stand-level susceptibility to mountain pine beetle attack. Spectral mixture analysis was used to determine the proportion of sunlit canopy and background, and shadow of each Landsat pixel enabling per pixel estimates of attributes required for model inversion. Stand structural attributes were then derived from inversion of the geometric optical model and used as basis for susceptibility mapping. Mean stand density estimated by the geometric optical model was 2753 (standard deviation ± 308) stems per hectare and mean horizontal crown radius was 2.09 (standard deviation ± 0.11) metres. When compared to equivalent forest inventory attributes, model predictions of stems per hectare and crown radius were shown to be reasonably estimated using a Kruskal-Wallis ANOVA (p < 0.001). These predictions were then used to create a large area map that provided an assessment of the forest area susceptible to mountain pine beetle damage.

  13. Oleic Acid Metabolism via a Conserved Cytochrome P450 System-Mediated ω-Hydroxylation in the Bark Beetle-Associated Fungus Grosmannia clavigera

    PubMed Central

    Novak, Metka; Lah, Ljerka; Šala, Martin; Stojan, Jure; Bohlmann, Joerg; Komel, Radovan

    2015-01-01

    The bark beetle-associated fungus Grosmannia clavigera participates in the large-scale destruction of pine forests. In the tree, it must tolerate saturating levels of toxic conifer defense chemicals (e.g. monoterpenes). The fungus can metabolize some of these compounds through the ß-oxidation pathway and use them as a source of carbon. It also uses carbon from pine triglycerides, where oleic acid is the most common fatty acid. High levels of free fatty acids, however, are toxic and can cause additional stress during host colonization. Fatty acids induce expression of neighboring genes encoding a cytochrome P450 (CYP630B18) and its redox partner, cytochrome P450 reductase (CPR2). The aim of this work was to study the function of this novel P450 system. Using LC/MS, we biochemically characterized CYP630 as a highly specific oleic acid ω-hydroxylase. We explain oleic acid specificity using protein interaction modeling. Our results underscore the importance of ω-oxidation when the main ß-oxidation pathway may be overwhelmed by other substrates such as host terpenoid compounds. Because this CYP-CPR gene cluster is evolutionarily conserved, our work has implications for metabolism studies in other fungi. PMID:25794012

  14. Oleic acid metabolism via a conserved cytochrome P450 system-mediated ω-hydroxylation in the bark beetle-associated fungus Grosmannia clavigera.

    PubMed

    Novak, Metka; Lah, Ljerka; Šala, Martin; Stojan, Jure; Bohlmann, Joerg; Komel, Radovan

    2015-01-01

    The bark beetle-associated fungus Grosmannia clavigera participates in the large-scale destruction of pine forests. In the tree, it must tolerate saturating levels of toxic conifer defense chemicals (e.g. monoterpenes). The fungus can metabolize some of these compounds through the ß-oxidation pathway and use them as a source of carbon. It also uses carbon from pine triglycerides, where oleic acid is the most common fatty acid. High levels of free fatty acids, however, are toxic and can cause additional stress during host colonization. Fatty acids induce expression of neighboring genes encoding a cytochrome P450 (CYP630B18) and its redox partner, cytochrome P450 reductase (CPR2). The aim of this work was to study the function of this novel P450 system. Using LC/MS, we biochemically characterized CYP630 as a highly specific oleic acid ω-hydroxylase. We explain oleic acid specificity using protein interaction modeling. Our results underscore the importance of ω-oxidation when the main ß-oxidation pathway may be overwhelmed by other substrates such as host terpenoid compounds. Because this CYP-CPR gene cluster is evolutionarily conserved, our work has implications for metabolism studies in other fungi.

  15. The carbon isotopic composition of soil respiration in the decade following disturbance by bark beetle or stem girdling

    NASA Astrophysics Data System (ADS)

    Chan, A.; Maurer, G. E.; Bowling, D. R.

    2013-12-01

    Recent outbreaks of mountain pine beetle have caused large-scale tree mortality in western North America, which can lead to fundamental changes in carbon cycling. When a tree is infested, the flow of photosynthate is disrupted. This causes the roots and their symbionts to die, eliminating the autotrophic component of soil respiration. Mycorrhizal fungi are enriched in 13C compared to plant tissues. As the dead fungal biomass is consumed by soil heterotrophs, the δ13C of CO2 in heterotrophic soil respiration may become more enriched as the fungal biomass is consumed. We investigated this response by measuring soil respiration in chronosequences of stem-girdled plots at the Niwot Ridge AmeriFlux site, and beetle-killed plots at the Fraser Experimental Forest, both in Colorado. Stem girdling was used to simulate beetle attack because it kills trees by a similar mechanism. Plots at Niwot Ridge included live trees and 7 years of girdled plots extending back to 2002. Plots at Fraser included live trees and three age classes of beetle-killed trees, within a similar chronosequence. We used manual soil-gas sampling at three depths, during the summers of 2011 and 2012, to determine if there is an isotopic effect associated with disturbance. Consistent with our expectations, in 2011, we found an enrichment in δ13C of approximately 1‰ in the two years following girdling which was absent in subsequent years. Although this pattern was also evident in 2012, the enrichment in δ13C during the same time period was about half that in 2011. At both Niwot and Fraser, in 2011, seasonal mean δ13C decreased by about 1‰ at all depths 3-4 years after disturbance, but returned to values close to control plots in the following 4-6 years. While we found a similar pattern at Fraser in 2012, we measured an enrichment of 1-1.5‰ at the OA interface at Niwot 8-10 years after disturbance, which was not found in 2011. It is possible this is due to the decomposition of woody biomass. At both

  16. Excess of Organic Carbon in Mountain Spruce Forest Soils after Bark Beetle Outbreak Altered Microbial N Transformations and Mitigated N-Saturation.

    PubMed

    Kaňa, Jiří; Tahovská, Karolina; Kopáček, Jiří; Šantrůčková, Hana

    2015-01-01

    Mountain forests in National park Bohemian Forest (Czech Republic) were affected by bark beetle attack and windthrows in 2004-2008, followed by an extensive tree dieback. We evaluated changes in the biochemistry of the uppermost soil horizons with the emphasis on carbon (C) and nitrogen (N) cycling in a near-natural spruce (Picea abies) mountain forest after the forest dieback, and compared it with an undisturbed control plot of similar age, climate, elevation, deposition, N-saturation level, and land use history. We hypothesised that the high litter input after forest dieback at the disturbed plot and its consequent decomposition might influence the availability of C for microorganisms, and consequently, N transformations in the soil. The concentrations of dissolved organic C (DOC) and N (DON) in soil water extracts rapidly increased at the disturbed plot for 3 yeas and then continually decreased. Net ammonification exhibited a similar trend as DOC and DON, indicating elevated mineralization. Despite the high ammonium concentrations found after the forest dieback (an increase from 0.5 mmol kg-1 to 2-3 mmol kg-1), net nitrification was stable and low during these 3 years. After the DOC depletion and decrease in microbial biomass 5 years after the forest dieback, net nitrification started to rise, and nitrate concentrations increased from 0.2-1 mmol kg-1 to 2-3 mmol kg-1. Our results emphasize the key role of the availability of organic C in microbial N transformations, which probably promoted microbial heterotrophic activity at the expense of slow-growing nitrifiers.

  17. Comparative phylogeography, genetic differentiation and contrasting reproductive modes in three fungal symbionts of a multipartite bark beetle symbiosis.

    PubMed

    Roe, Amanda D; Rice, Adrianne V; Coltman, David W; Cooke, Janice E K; Sperling, Felix A H

    2011-02-01

    Multipartite symbioses are complex symbiotic relationships involving multiple interacting partners. These types of partnerships provide excellent opportunities in which to apply a comparative approach to identify common historical patterns of population differentiation and species-specific life history traits. Using three symbiotic blue-stain fungal species (Ophiostomatacea) associated with outbreaking populations of the mountain pine beetle (Dendroctonus ponderosae Hopkins) in western Canada, we applied phylogenetic, population genetic and demographic approaches to clarify phylogeographic patterns among the three fungal species. Broadly, the three species showed significant population differentiation, forming northern and southern populations, despite dramatic differences in haplotype diversity. Finer structuring and population demographic patterns were less consistent, showing some interspecific incongruence. By contrasting these species simultaneously, we were able to identify differences in recombination rate and ecological traits that can explain the observed patterns of incongruence among the fungal species. By applying a comparative approach to partners of a multipartite symbiosis, we were able to distinguish congruent population structuring and species-specific differences that help us to understand the complexity and evolution of this symbiotic system.

  18. Fortifying the forest: thinning and burning increase resistance to a bark beetle outbreak and promote forest resilience.

    PubMed

    Hood, Sharon M; Baker, Stephen; Sala, Anna

    2016-10-01

    Fire frequency in low-elevation coniferous forests in western North America has greatly declined since the late 1800s. In many areas, this has increased tree density and the proportion of shade-tolerant species, reduced resource availability, and increased forest susceptibility to forest insect pests and high-severity wildfire. In response, treatments are often implemented with the goal of increasing ecosystem resilience by increasing resistance to disturbance. We capitalized on an existing replicated study of fire and stand density treatments in a ponderosa pine (Pinus ponderosa)-Douglas-fir (Pseudotsuga menziesii) forest in western Montana, USA, that experienced a naturally occurring mountain pine beetle (MPB; Dendroctonus ponderosae) outbreak 5 yr after implementation of fuels treatments. We explored whether treatment effects on tree-level defense and stand structure affected resistance to MPB. Mortality from MPB was highest in the denser, untreated control and burn-only treatments, with approximately 50% and 39%, respectively, of ponderosa pine killed during the outbreak, compared to almost no mortality in the thin-only and thin-burn treatments. Thinning treatments, with or without fire, dramatically increased tree growth and resin ducts relative to control and burn-only treatments. Prescribed burning did not increase resin ducts but did cause changes in resin chemistry that may have affected MPB communication and lowered attack success. While ponderosa pine remained dominant in the thin and thin-burn treatments after the outbreak, the high pine mortality in the control and burn-only treatment caused a shift in species dominance to Douglas-fir. The high Douglas-fir component in the control and burn-only treatments due to 20th century fire exclusion, coupled with high pine mortality from MPB, has likely reduced resilience of this forest beyond the ability to return to a ponderosa pine-dominated system in the absence of further fire or mechanical treatment. Our

  19. Trace gas emissions from a chronosequence of bark beetle-infested lodgepole pine (Pinus contorta) forest stands

    NASA Astrophysics Data System (ADS)

    Norton, U.; Pendall, E.; Ewers, B. E.; Borkhuu, B.

    2011-12-01

    Severe outbreak of mountain pine beetle (MPB) and associated blue stain fungi have killed millions of hectares of coniferous forests in Western North America. This unprecedented disturbance has critically impacted ecosystem biogeochemistry and net carbon (C) and nitrogen (N) fluxes. However, the effects on greenhouse gas (GHG) emissions and drivers of biogeochemical processes that trigger GHG emissions following MPB infestations are not well understood. Such information can help assess regional-level changes in ecosystem C and N budgets and large-scale disturbance impacts on gas exchange between the atmosphere and terrestrial ecosystem. The overall objective of this research was to assess the immediate responses of GHG fluxes and soil C and N mineralization rates along a chronosequence of recently infested (1-yr, 3-yr and 4-yr ago) and uninfested (150-yr, 20-yr and 15-yr old) lodgepole pine stands in Medicine Bow National Forest in southeastern Wyoming. We hypothesize that MPB-induced tree mortality significantly changes stand-level hydrology, soil organic matter quality and chemistry of aboveground and belowground plant inputs. Consequently, these modifications influence nitrous oxide (N2O) emissions and methane (CH4) assimilation. Biweekly GHG measurements using static chambers were carried out during three consecutive snow-free growing seasons. Our results suggest that a stand infested within a year already shows a 20% increase in spring N2O production and a small decline in summer CH4 assimilation when compared to uninfested stands. Stands infested three and four years prior to our measurements produce over three times more N2O and assimilate three to five times less CH4 when compared to uninfested stands. In addition, a notable increase in soil moisture content and soil mineral N concentrations following early onset of the MPB infestation was also observed. An overall increase in N2O production and decline in CH4 assimilation following MPB infestation may

  20. Nonstructural carbon dynamics are best predicted by the combination of photosynthesis and plant hydraulics during both bark beetle induced mortality and herbaceous plant response to drought

    NASA Astrophysics Data System (ADS)

    Ewers, B. E.; Mackay, D. S.; Guadagno, C.; Peckham, S. D.; Pendall, E.; Borkhuu, B.; Aston, T.; Frank, J. M.; Massman, W. J.; Reed, D. E.; Yarkhunova, Y.; Weinig, C.

    2012-12-01

    Recent work has shown that nonstructural carbon (NSC) provides both a signal and consequence of water stress in plants. The dynamics of NSC are likely not solely a result of the balance of photosynthesis and respiration (carbon starvation hypothesis) but also the availability of NSC for plant functions due to hydraulic condition. Further, plant hydraulics regulates photosynthesis both directly through stomatal conductance and indirectly through leaf water status control over leaf biochemistry. To test these hypotheses concerning NSC in response to a wide variety of plant perturbations, we used a model that combines leaf biochemical controls over photosynthesis (Farquhar model) with dynamic plant hydraulic conductance (Sperry model). This model (Terrestrial Regional Ecosystem Exchange Simulator; TREES) simulates the dynamics of NSC through a carbon budget approach that responds to plant hydraulic status. We tested TREES on two dramatically different datasets. The first dataset is from lodgepole pine and Engelmann spruce trees dying from bark beetles that carry blue-stain fungi which block xylem and cause hydraulic failure. The second data set is from Brassica rapa, a small herbaceous plant whose accessions are used in a variety of crops. The Brassica rapa plants include two parents whose circadian clock periods are different; NSC is known to provide inputs to the circadian clock likely modified by drought. Thus, drought may interact with clock control to constrain how NSC changes over the day. The Brassica rapa plants were grown in growth chamber conditions where drought was precisely controlled. The connection between these datasets is that both provide rigorous tests of our understanding of plant NSC dynamics and use similar leaf and whole plant gas exchange and NSC laboratory methods. Our results show that NSC decline (<10% in the whole plant) is less precipitous than expected from carbon starvation alone because both C uptake and use are impacted by water stress

  1. 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

  2. Implementing the Effects of Changing Landscape by the Recent Bark Beetle Infestation on Snow Accumulation and Ablation to More Accurately Predict Stream Flow in the Upper Little Laramie River, Wyoming watershed.

    NASA Astrophysics Data System (ADS)

    Heward, J.; Ohara, N.

    2014-12-01

    In many alpine regions, especially in the western United States, the snow pack is the cause of the peak discharge and most of the annual flow. A distributed snow melt model with a point-scale snow melt theory is used to estimate the timing and intensity of both snow accumulation and ablation. The type and distribution of vegetation across a watershed influences timing and intensity of snow melt processes. Efforts are being made to understand how a changing landscape will ultimately affect stream flow in a mountainous environment. This study includes an analysis of the effects of the recent bark beetle infestation, using leaf area index (LAI) data acquired from MODIS data sets. These changes were incorporated into the snow model to more accurately predict snow melt timing and intensity. It was observed through the primary model implementation that snowmelt was intensified by the LAI reduction. The radiation change and turbulent flux effects were separately quantified by the vegetation parameterization in the snow model. This distributed snow model will be used to more accurately predict stream flow in the Upper Little Laramie River, Wyoming watershed.

  3. Evaluation of insecticides for protecting Southwestern ponderosa pines from attack by engraver beetles (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    DeGomez, Tom E; Hayes, Christopher J; Anhold, John A; McMillin, Joel D; Clancy, Karen M; Bosu, Paul P

    2006-04-01

    Insecticides that might protect pine trees from attack by engraver beetles (Ips spp.) have not been rigorously tested in the southwestern United States. We conducted two field experiments to evaluate the efficacy of several currently and potentially labeled preventative insecticides for protecting high-value ponderosa pine, Pinus ponderosa Dougl ex. Laws., from attack by engraver beetles. Preventative sprays (0.19% permethrin [Permethrin Plus C]; 0.03, 0.06, and 0.12% bifenthrin [Onyx]; and 1.0 and 2.0% carbaryl [Sevin SL] formulations) and systemic implants (0.875 g per capsule acephate [Acecap] and 0.650 g per capsule dinotefuran) were assessed on bolts (sections of logs) as a surrogate for live trees for a period of 13 mo posttreatment. The pine engraver, Ips pini (Say), was the most common bark beetle found attacking control and treated bolts, but sixspined ips, Ips calligraphus (Germar), and Ips lecontei Swain also were present. After approximately 13 mo posttreatment in one experiment, the spray treatments with 2.0% carbaryl, 0.19% permethrin, and 0.06 or 0.12% bifenthrin prevented Ips attack on the bolts at a protection level of > or = 70%. The acephate and dinotefuran systemic insecticides, and the 0.03% bifenthrin spray, provided inadequate (< or = 36%) protection in this experiment. For the other experiment, sprayed applications of 1.0% carbaryl, 0.19% permethrin, and 0.06% bifenthrin prevented beetle attack at protection levels of > or = 90, > or = 80, and > or = 70%, respectively, when bolts were exposed to Ips beetle attack for approximately 9-15 wk posttreatment. The sprays with 0.19% permethrin and 0.06% bifenthrin also provided > or = 90% protection when bolts were exposed for approximately 15-54 wk posttreatment. We concluded that under the conditions tested, 1.0 and 2.0% carbaryl, 0.19% permethrin, and 0.06 and 0.12% binfenthrin were acceptable preventative treatments for protecting ponderosa pine from successful engraver beetle attack for one

  4. 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.

  5. Molecular Markers Detect Cryptic Predation on Coffee Berry Borer (Coleoptera: Curculionidae) by Silvanid and Laemophloeid Flat Bark Beetles (Coleoptera: Silvanidae, Laemophloeidae) in Coffee Beans.

    PubMed

    Sim, Sheina B; Yoneishi, Nicole M; Brill, Eva; Geib, Scott M; Follett, Peter A

    2016-02-01

    The coffee berry borer, Hypothenemus hampei (Ferrari) (Coleoptera: Curculionidae), is a serious pest of coffee worldwide. It was first detected in Hawai'i in 2010. Two predatory beetles, Cathartus quadricollis (Coleoptera: Silvanidae) and Leptophloeus sp. (Coleoptera: Laemophloeidae), have been observed in H. hampei-infested coffee. Under laboratory conditions, colony-reared C. quadricollis and Leptophloeus sp. prey upon all life stages of H. hampei. However, the H. hampei life cycle occurs almost exclusively within a coffee bean obscured from direct observation. Thus, it is unknown if C. quadricollis and Leptophloeus sp. consume H. hampei as prey in the wild. To demonstrate predation of H. hampei by C. quadricollis and Leptophloeus sp., a molecular assay was developed utilizing species-specific primers targeting short regions of the mitochondrial COI gene to determine species presence. Using these primers, wild C. quadricollis and Leptophloeus sp. were collected and screened for the presence of H. hampei DNA using PCR. Analysis of collections from five coffee farms revealed predation of C. quadricollis and Leptophloeus sp. on H. hampei. Further laboratory testing showed that H. hampei DNA could be detected in predators for as long as 48 h after feeding, indicating the farm-caught predators had preyed on H. hampei within 2 d of sampling. This study demonstrates the utility of molecular markers for the study of the ecology of predators and prey with cryptic behavior, and suggests C. quadricollis and Leptophloeus sp. might be useful biocontrol agents against H. hampei.

  6. 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.

  7. [Parasitism of Ips sexdentatus (Insecta: Scolytidae) by Parasitorhabditis ipsophila (Nematoda: Rhabditidae)].

    PubMed

    Lieutier, F

    1984-01-01

    The study of parasitism percentages and contaminations intensity in Ips sexdentatus parasitized by P. ipsophila as well as the examination of the wormholes in the galleries of the bark beetle gave better insight into certain features of nematode biology. Larvae of I. sexdentatus could be infected, whereas pupae could not. Adults were contaminated from initial stages of maturation and throughout preswarming maturation. Following swarming and installation on a new tree, insects were rapidly decontaminated, but recontamination could occur by the end of oviposition. P. ipsophila larvae were found in the mesenteron before they penetrated into the hind gut. Seemingly, the parasite underwent no evolution within its host. All developmental stages of the nematode could be observed in the galleries of the bark beetle as long as the latter was present. No apparent relation exists between parasitism of the digestive tract by P. ipsophila and parasitism of the body or fat body by Parasitaphelenchus or Contortylenchus diplogaster. P. ipsophila exerts very limited effects on I. sexdentatus populations. A slight delay in swarming and initiation of oviposition, and a very low decrease in density of notches of oviposition and of eggs was observed, but the features of the gallery of oviposition (total length, length before the first notch) showed no alteration. No mortality was detected.

  8. Functional characterization of myrcene hydroxylases from two geographically distinct Ips pini populations.

    PubMed

    Song, Minmin; Kim, Amy C; Gorzalski, Andrew J; MacLean, Marina; Young, Sharon; Ginzel, Matthew D; Blomquist, Gary J; Tittiger, Claus

    2013-04-01

    Ips pini bark beetles use myrcene hydroxylases to produce the aggregation pheromone component, ipsdienol, from myrcene. The enantiomeric ratio of pheromonal ipsdienol is an important prezygotic mating isolation mechanism of I. pini and differs among geographically distinct populations. We explored the substrate and product ranges of myrcene hydroxylases (CYP9T2 and CYP9T3) from reproductively-isolated western and eastern I. pini. The two cytochromes P450 share 94% amino acid identity. CYP9T2 mRNA levels were not induced in adults exposed to myrcene-saturated atmosphere. Functional assays of recombinant enzymes showed both hydroxylated myrcene, (+)- and (-)-α-pinene, 3-carene, and R-(+)-limonene, but not α-phellandrene, (-)-β-pinene, γ-terpinene, or terpinolene, with evidence that CYP9T2 strongly preferred myrcene over other substrates. They differed in the enantiomeric ratios of ipsdienol produced from myrcene, and in the products resulting from different α-pinene enantiomers. These data provide new information regarding bark beetle pheromone evolution and factors affecting cytochrome P450 structure-function relationships.

  9. Predictors of Ips confusus Outbreaks During a Record Drought in Southwestern USA: Implications for Monitoring and Management

    NASA Astrophysics Data System (ADS)

    Santos, Maria J.; Whitham, Thomas G.

    2010-02-01

    In many ecosystems the effects of disturbance can be cryptic and disturbance may vary in subtle spatiotemporal ways. For instance, we know that bark beetle outbreaks are more frequent in temperate forests during droughts; however, we have little idea about why they occur in some locations and not others. Understanding biotic and abiotic factors promoting bark beetle outbreaks can be critical to predicting and responding to pest outbreaks. Here we address the environmental factors which are associated with Ips confusus outbreaks during the 2002 widespread drought within the distribution range of pinyon pine woodlands in Arizona. We used univariate statistics to test if whether tree characteristics, other herbivores, stand properties, soil type, wind, and topography were associated with I. confusus outbreak, and logistic regression to create a predictive model for the outbreaks. We found that I. confusus attacks occur in low elevation stands on steeper slopes, where favorable winds for I. confusus dispersion occur. I. confusus select larger trees, in high density stands with understory shrubs that exhibit phenotypic traits characteristic of resistance to stem-boring moths. The model was highly accurate, and explained 95% of the variability in occurrence (98% of the absences and 95% of the presences). Accurate prediction of the impacts of disturbance allow us to anticipate, minimize or mitigate for and eventually counteract its effects, especially those affecting diversity and ecosystem function. Identification of outbreak risk areas can guide regional and national management towards the reduction of infestation risk and enhancing conservation of pinyon-juniper woodlands.

  10. 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.

  11. 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.

  12. Feeding response of Ips paraconfusus to phloem and phloem metabolites of Heterobasidion annosum-inoculated ponderosa pine, Pinus ponderosa.

    PubMed

    McNee, William R; Bonello, Pierluigi; Storer, Andrew J; Wood, David L; Gordon, Thomas R

    2003-05-01

    In studies of feeding by the bark beetle, Ips paraconfusus, two pine stilbenes (pinosylvin and pinosylvin methyl ether), ferulic acid glucoside, and enantiomers of the four most common sugars present in ponderosa pine phloem (sucrose, glucose, fructose, and raffinose) did not stimulate or reduce male feeding when assayed on wet alpha-cellulose with or without stimulatory phloem extractives present. When allowed to feed on wet alpha-cellulose containing sequential extracts (hexane, methanol, and water) of ponderosa pine phloem, methanol and water extractives stimulated feeding, but hexane extractives did not. Males confined in wet alpha-cellulose containing aqueous or organic extracts of culture broths derived from phloem tissue and containing the root pathogen. Heterobasidion annosum, ingested less substrate than beetles confined to control preparations. In an assay using logs from uninoculated ponderosa pines, the mean lengths of phloem in the digestive tracts increased as time spent feeding increased. Males confined to the phloem of basal logs cut from ponderosa pines artificially inoculated with H. annosum ingested significantly less phloem than beetles in logs cut from trees that were (combined) mock-inoculated or uninoculated and did not contain the pathogen. However, individual pathogen-containing treatments were not significantly different from uninoculated controls. It was concluded that altered feeding rates are not a major factor which may explain why diseased ponderosa pines are colonized by I. paraconfusus.

  13. Efficacy of imidacloprid, trunk-injected into Acer platanoides, for control of adult Asian longhorned beetles (Coleoptera: Cerambycidae).

    PubMed

    Ugine, Todd A; Gardescu, Sana; Lewis, Phillip A; Hajek, Ann E

    2012-12-01

    Feeding experiments with Asian longhorned beetles (Anoplophora glabripennis (Motschulsky)) in a quarantine laboratory were used to assess the effectiveness of imidacloprid in reducing adult fecundity and survival. The beetles were fed twigs and leaves cut between June-September 2010 from Norway maples (Acer platanoides L.) in the beetle-infested area of Worcester, MA. Treated trees had been trunk-injected once with imidacloprid in spring 2010 under the U.S. Department of Agriculture-Animal and Plant Health Inspection Service operational eradication program. The 21 d LC50 value for adult beetles feeding on twig bark from imidacloprid-injected trees was 1.3 ppm. Adult reproductive output and survival were significantly reduced when beetles fed on twig bark or leaves from treated trees. However, results varied widely, with many twig samples having no detectable imidacloprid and little effect on the beetles. When twigs with > 1 ppm imidacloprid in the bark were fed to mated beetles, the number of larvae produced was reduced by 94% and median adult survival was reduced to 14 d. For twigs with < 1 ppm imidacloprid, 68% of reproductively mature mated beetles survived 21 d and 56% of unmated recently eclosed beetles survived 42 d. For twigs with < 1 ppm, beetles ingested an average of 30 nanograms of imidacloprid per day. Bark consumption was reduced at higher imidacloprid levels (> 1 ppm). When given a choice of control twigs and twigs from injected trees, beetles did not show a strong preference.

  14. The evolution of agriculture in beetles (Curculionidae: Scolytinae and Platypodinae).

    PubMed

    Farrell, B D; Sequeira, A S; O'Meara, B C; Normark, B B; Chung, J H; Jordal, B H

    2001-10-01

    Beetles in the weevil subfamilies Scolytinae and Platypodinae are unusual in that they burrow as adults inside trees for feeding and oviposition. Some of these beetles are known as ambrosia beetles for their obligate mutualisms with asexual fungi--known as ambrosia fungi--that are derived from plant pathogens in the ascomycete group known as the ophiostomatoid fungi. Other beetles in these subfamilies are known as bark beetles and are associated with free-living, pathogenic ophiostomatoid fungi that facilitate beetle attack of phloem of trees with resin defenses. Using DNA sequences from six genes, including both copies of the nuclear gene encoding enolase, we performed a molecular phylogenetic study of bark and ambrosia beetles across these two subfamilies to establish the rate and direction of changes in life histories and their consequences for diversification. The ambrosia beetle habits have evolved repeatedly and are unreversed. The subfamily Platypodinae is derived from within the Scolytinae, near the tribe Scolytini. Comparison of the molecular branch lengths of ambrosia beetles and ambrosia fungi reveals a strong correlation, which a fungal molecular clock suggests spans 60 to 21 million years. Bark beetles have shifted from ancestral association with conifers to angiosperms and back again several times. Each shift to angiosperms is associated with elevated diversity, whereas the reverse shifts to conifers are associated with lowered diversity. The unusual habit of adult burrowing likely facilitated the diversification of these beetle-fungus associations, enabling them to use the biomass-rich resource that trees represent and set the stage for at least one origin of eusociality.

  15. Weaning off Bark

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pine bark is the primary potting component used in container nursery production. Shifts in the forest products industry and economy have resulted in a drastic decline in pine bark availability and increase in pine bark price. Scientists at the USDA-ARS Application Technology Research Unit, Oregon ...

  16. Barking and mobbing.

    PubMed

    Lord, Kathryn; Feinstein, Mark; Coppinger, Raymond

    2009-07-01

    Barking is most often associated with the domestic dog Canis familiaris, but it is a common mammalian and avian vocalization. Like any vocalization, the acoustic character of the bark is likely to be a product of adaptation as well as an expression of the signaler's internal motivational state. While most authors recognize that the bark is a distinct signal type, no consistent description of its acoustic definition or function is apparent. The bark exhibits considerable variability in its acoustic form and occurs in a wide range of behavioral contexts, particularly in dogs. This has led some authors to suggest that dog barking might be a form of referential signaling, or an adaptation for heightened capability to communicate with humans. In this paper we propose a general 'canonical' acoustic description of the bark. Surveying relevant literature on dogs, wild canids, other mammals and birds, we explore an alternative functional hypothesis, first suggested by [Morton, E.S., 1977. On the occurrence and significance of motivation-structural rules in some bird and mammal sounds. Am. Nat. 111, 855-869] and consistent with his motivational-structural rules theory: that barking in many animals, including the domestic dog, is associated with mobbing behavior and the motivational states that accompany mobbing.

  17. 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

  18. Do Phoretic Mites Influence the Reproductive Success of Ips grandicollis (Coleoptera: Curculionidae)?

    PubMed

    Pfammatter, Jesse A; Raffa, Kenneth F

    2015-12-01

    Ips grandicollis (Eichhoff) can be an important pest of plantation trees in the Great Lakes region. Mites commonly occur in phoretic association with this beetle, but little is known about their effects on beetle population dynamics. We assessed the effects of phoretic mites on the reproductive success of I. grandicollis using complementary correlative and manipulative approaches. First, we allowed beetles to colonize Pinus resinosa (Ait) logs from sites across Wisconsin, reared them in a common environment, and related the species identities and abundances of mites with beetle production from each log. We found a positive relationship between I. grandicollis abundance and the presence of five mite species, Histiostoma spp., Dendrolaelaps quadrisetus (Berlese), Iponemus confusus (Lindquist), Trichouropoda australis Hirschmann, and Tarsonemus spp. While the abundance of individual mite species was positively correlated with beetle abundance, assessments of mite community structure did not explain beetle reproduction. Next, we introduced beetles that either had a natural complement of mites or whose mites were mechanically reduced into logs, and compared reproductive success between these beetles. We found no difference in colonization rates or beetle emergence between mite-present and mite-reduced treatments. Collectively, these results suggest a correlative, rather than causal, link between beetle reproductive success and mite incidence and abundances. These mites and beetles likely benefit from mutually suitable environments rather than exerting strong reciprocal impacts. Although mites may have some effects on I. grandicollis reproductive success, they likely play a minimal role compared to factors such as tree quality, beetle predation, and weather.

  19. Antinociceptive activity of Maytenus rigida stem bark.

    PubMed

    Dias, Kellyane S; Marques, Maxsuel S; Menezes, Igor A C; Santos, Thiago C; Silva, Aline B L; Estevam, Charles S; Sant'Ana, Antônio E G; Pizza, Cosimo; Antoniolli, Angelo R; Marçal, Rosilene M

    2007-12-01

    Ethanol extract of Maytenus rigida stem bark and its fractions were assessed for antinociceptive activity in tail-flick test in rats. The activity was located in the chloroform, ethyl acetate and aq.methanol fractions. Phytochemical screening revealed that catechin was the only common class of compounds present on the ethanol extract as well as on the active fractions. 4'-Methylepigallocatechin, isolated from the ethyl acetate and aq.methanol fractions, showed antinociceptive effect in the tail-flick test (75 mg/kg; p.o.), which was reversed by the opiate antagonist naloxone (3 mg/kg; i.p.).

  20. Interruption of the semiochemical-based attraction of ambrosia beetles to ethanol-baited traps and ethanol-injected trap trees by Verbenone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We examined the ability of verbenone, a bark beetle anti-aggregation pheromone, to interrupt the semiochemical-based attraction of ambrosia beetles. Field trapping studies conducted in Ohio showed that a verbenone dispenser with a release rate of 50 mg / d at 25 oC reduced the attraction of Anisandr...

  1. Presence of carbaryl in the smoke of treated lodgepole and ponderosa pine bark

    NASA Astrophysics Data System (ADS)

    Peterson, Chris J.; Costello, Sheryl L.

    2013-02-01

    Lodgepole and ponderosa pine trees were treated with a 2% carbaryl solution at recreational areas near Fort Collins, CO, in June 2010 as a prophylactic bole spray against the mountain pine beetle. Bark samples from treated and untreated trees were collected one day following application and at 4-month intervals for one year. The residual amount of carbaryl was determined, and bark samples were burned to examine the smoke for the active ingredient. Smoke recovered from spiked bark samples showed a very high correlation between the treated rate and the concentration recovered from the smoke. Residual carbaryl on the bark was relatively stable throughout the study and carbaryl was detected in the smoke throughout the duration of the test.

  2. 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.

  3. Amate Bark Designs

    ERIC Educational Resources Information Center

    Mazur, Matt

    2013-01-01

    Inspired by a beautiful bookmark one of the author's students made for him as a gift, he began a lesson exploring the vibrant bark paintings popular all over Mexico. The majority of his students have Mexican ancestry, so exploring the arts of Mexico is always popular and well received. Amate paintings can also be a great way to introduce the…

  4. Landscape-scale analysis of aboveground tree carbon stocks affected by mountain pine beetles in Idaho

    NASA Astrophysics Data System (ADS)

    Bright, B. C.; Hicke, J. A.; Hudak, A. T.

    2012-12-01

    Bark beetle outbreaks kill billions of trees in western North America, and the resulting tree mortality can significantly impact local and regional carbon cycling. However, substantial variability in mortality occurs within outbreak areas. Our objective was to quantify landscape-scale effects of beetle infestations on aboveground carbon (AGC) stocks using field observations and remotely sensed data across a 5054 ha study area that had experienced a mountain pine beetle outbreak. Tree mortality was classified using multispectral imagery that separated green, red, and gray trees, and models relating field observations of AGC to LiDAR data were used to map AGC. We combined mortality and AGC maps to quantify AGC in beetle-killed trees. Thirty-nine per cent of the forested area was killed by beetles, with large spatial variability in mortality severity. For the entire study area, 40-50% of AGC was contained in beetle-killed trees. When considered on a per-hectare basis, 75-89% of the study area had >25% AGC in killed trees and 3-6% of the study area had >75% of the AGC in killed trees. Our results show that despite high variability in tree mortality within an outbreak area, bark beetle epidemics can have a large impact on AGC stocks at the landscape scale.

  5. 78 FR 46312 - Spruce Beetle Epidemic and Aspen Decline Management Response; Grand Mesa, Uncompahgre and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-31

    ... Gunnison National Forests (GMUG) has experienced mortality from insects and diseases over the past decade... Bark Beetle Strategy (July 2011) including: Promoting recovery from the insect outbreak, improving the...,000 acres of aspen forests have experienced substantial mortality from insects and diseases over...

  6. Microsclerotia of Metarhizium brunneum F52 Applied in Hydromulch for Control of Asian Longhorned Beetles (Coleoptera: Cerambycidae).

    PubMed

    Goble, Tarryn A; Hajek, Ann E; Jackson, Mark A; Gardescu, Sana

    2015-04-01

    The entomopathogenic fungus Metarhizium brunneum (Petch) strain F52 (Hypocreales: Clavicipitaceae) is able to produce environmentally persistent microsclerotia (hyphal aggregates). Microsclerotia of strain F52 produced as granules and incorporated into hydromulch (hydro-seeding straw, water, and a natural glue) provides a novel mycoinsecticide that could be sprayed onto urban, forest, or orchard trees. We tested this formulation against adult Asian longhorned beetles (Anoplophora glabripennis (Motschulsky)) using three substrates (moistened bark, dry bark, absorbent bench liner) sprayed with a low rate (9 microsclerotia granules/cm2) of hydromulch. Median survival times of beetles continuously exposed to sprayed moist bark or absorbent liner were 17.5 and 19.5 d, respectively. Beetles exposed to sprayed dry bark, which had a lower measured water activity, lived significantly longer. When moist bark pieces were sprayed with increased rates of microsclerotia granules in hydromulch, 50% died by 12.5 d at the highest application rate, significantly sooner than beetles exposed to lower application rates (16.5-17.5 d). To measure fecundity effects, hydromulch with or without microsclerotia was sprayed onto small logs and pairs of beetles were exposed for a 2-wk oviposition period in containers with 98 or 66% relative humidity. At 98% humidity, oviposition in the logs was highest for controls (18.3±1.4 viable offspring per female) versus 3.9±0.8 for beetles exposed to microsclerotia. At 66% humidity, fecundities of controls and beetles exposed to microsclerotia were not significantly different. This article presents the first evaluation of M. brunneum microsclerotia in hydromulch applied for control of an arboreal insect pest.

  7. A Study Of Ips Typographus Pest Infestation With The Use Of Multi-Angular CHRIS-Proba Data

    NASA Astrophysics Data System (ADS)

    Filchev, Lachezar; Panayotov, Momchil; Ling, Feilong

    2013-12-01

    Insects' infestations of coniferous forests have been in the focus of the forestry community for decades. Research that is dealing with the assessment of the impacts on forests and assessment of the area affected by the infestations has been assisted by remotely sensed data after the onset of civilian remote sensing era and making the large archives of satellite data centres of NASA, ESA, and JAXA available to the researcher's community. The present study assesses the impact from European Bark beetle (Ips typhographus L.) outbreak on Norway Spruce (Picea abies L.) forests in the UNESCO MAB reserve Bistrishko Branishte in Bulgaria using the ESA's third-party mission multiangular satellite CHRIS/PROBA Mode 1 spectroradiometer data. The study aims at assessing the impact of the infestation by comparing the pre- and post-fire CHRIS/PROBA Mode 1 narrow-band vegetation indices (VIs). In order to achieve the study objective the ‘dead spruce forest' areas were extracted using eight target detection algorithms. Statistics from the CHRIS/PROBA Mode 1 VIs was drawn and compared with one another for the two dates of acquisition. It was found that the areas affected by pest infestation can be well differentiated on CHRIS/PROBA data but the results vary due to the date of acquisition, illumination conditions, and season changes. The results from the study suggest that continuous space monitoring of insect infested coniferous forests can be successfully carried out by employing present-day available hyperspectral satellite data.

  8. The Role of the Beetle Hypocryphalus mangiferae (Coleoptera: Curculionidae) in the Spatiotemporal Dynamics of Mango Wilt.

    PubMed

    Galdino, Tarcísio Visintin da Silva; Ferreira, Dalton de Oliveira; Santana Júnior, Paulo Antônio; Arcanjo, Lucas de Paulo; Queiroz, Elenir Aparecida; Sarmento, Renato Almeida; Picanço, Marcelo Coutinho

    2017-03-03

    The knowledge of the spatiotemporal dynamics of pathogens and their vectors is an important step in determining the pathogen dispersion pattern and the role of vectors in disease dynamics. However, in the case of mango wilt little is known about its spatiotemporal dynamics and the relationship of its vector [the beetle Hypocryphalus mangiferae (Stebbing 1914)] to these dynamics. The aim of this work was to determine the spatial-seasonal dynamic of H. mangiferae attacks and mango wilt in mango orchards and to verify the importance of H. mangiferae in the spatiotemporal dynamics of the disease. Two mango orchards were monitored during a period of 3 yr. The plants in these orchards were georeferenced and inspected monthly to quantify the number of plants attacked by beetles and the fungus. In these orchards, the percentage of mango trees attacked by beetles was always higher than the percentage infected by the fungus. The colonization of mango trees by beetles and the fungus occurred by colonization of trees both distant and proximal to previously attacked trees. The new plants attacked by the fungus emerged in places where the beetles had previously begun their attack. This phenomenon led to a large overlap in sites of beetle and fungal occurrence, indicating that establishment by the beetle was followed by establishment by the fungus. This information can be used by farmers to predict disease infection, and to control bark beetle infestation in mango orchards.

  9. Climate and recent mountain pine beetle outbreaks in the western United States

    NASA Astrophysics Data System (ADS)

    Hicke, J. A.; Creeden, E.; Buotte, P.

    2013-12-01

    Bark beetle outbreaks have killed billions of trees in western North America, affecting biogeochemical and biogeophysical processes that lead to impacts on weather, climate, and hydrology. Climate is a known factor influencing these outbreaks, and recent climate change has been linked to some outbreaks. Our objective was to document the patterns of climate (weather) variables before and throughout five major outbreaks of mountain pine beetle in the western United States. We assessed climate variables that influence beetle outbreaks in different ways: winter temperatures that lead to beetle mortality; year-round temperatures that affect beetle development rates and influence attack dynamics; and drought, which increases host stress and susceptibility to attack. We found significant differences in mean climate among outbreak locations. Temperatures were typically higher in outbreak years than in prior years, suggesting that recent anthropogenic warming may have played a role in influencing these events. Drought was present during the earlier stages of the outbreaks, and relief from drought in later stages did not result in beetle population declines. Temperatures that were not favorable for the beetle did not coincide with outbreak declines, suggesting that host depletion, not climate, was the cause. Our results increase the understanding of the role of climate in driving outbreaks of mountain pine beetle, and will lead to more accurate projections of future disturbances in the face of expected future climate change.

  10. Reproductive Isolation of Ips nitidus and I. shangrila in Mountain Forests of Western China: Responses to Chiral and Achiral Candidate Pheromone Components.

    PubMed

    Schlyter, Fredrik; Jakuš, Rastislav; Han, Fu-Zhong; Ma, Jian-Hai; Kalinová, Blanka; Mezei, Pavel; Sun, Jiang-Hua; Ujhelyiová, Liana; Zhang, Qing-He

    2015-07-01

    Eastern Palearctic conifers are subject to frequent bark beetle outbreaks. However, neither the species responsible nor the semiochemicals guiding these attacks are well understood. Two high-mountain Ips species on Qinghai spruce, Picea crassifolia, I. shangrila and I. nitidus, are typical in this regard. Six synthetic candidate pheromone components that we earlier identified from hindguts of unmated males of these two Ips species were tested for field activity in Qinghai province, P. R. China. For I. nitidus, racemic ipsdienol ((±)-Id) could replace the naturally-produced blend of enantiomers containing 74% (-)-(S)-Id (74:26 S:R), in attractive ternary or binary blends. In contrast, sympatric I. shangrila were attracted mainly to blends including Id of opposite chirality, 97%-(+)-(R)-Id. Of the verbenols, (-)-trans-verbenol was inactive for I. nitidus or inhibitory for I. shangrila, but (-)-cis-verbenol (cV) was a key component of the pheromone in both species. Two fully factorial experiments demonstrated that (±)-Id, cV, and 2-methyl-3-buten-2-ol (MB) are components of the aggregation pheromone of I. nitidus, whereas only (+)-Id and cV are essential components of the aggregation pheromone of I. shangrila. While MB is not necessary for attraction of I. shangrila, it is an active antagonist and likely functions in species isolation. A review of the pheromone production and responses in Palearctic Ips and Pseudoips showed that cV is more common than methylbutenols, and both elicit qualitatively variable responses. Ipsdienol is the most common component with variable chirality, and is a necessary, but often not sufficient, factor for determining pheromone specificity.

  11. 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.

  12. Efficacy of systemic insecticides for protection of loblolly pine against southern pine engraver beetles (Coleoptera: Curculionidae: Scolytinae) and wood borers (Coleoptera: Cerambycidae).

    PubMed

    Grosman, Donald M; Upton, William W

    2006-02-01

    We evaluated the efficacy of the systemic insecticides dinotefuran, emamectin benzoate, fipronil, and imidacloprid for preventing attacks and brood production of southern pine engraver beetles (Coleoptera: Curculionidae: Scolytinae) and wood borers (Coleoptera: Cerambycidae) on standing, stressed trees and bolt sections of loblolly pine, Pinus taeda L., in eastern Texas. Emamectin benzoate significantly reduced the colonization success of engraver beetles and associated wood borers in both stressed trees and pine bolt sections. Fipronil was nearly as effective as emamectin benzoate in reducing insect colonization of bolts 3 and 5 mo after injection but only moderately effective 1 mo after injection. Fipronil also significantly reduced bark beetle-caused mortality of stressed trees. Imidacloprid and dinotefuran were ineffective in preventing bark beetle and wood borer colonization of bolts or standing, stressed trees. The injected formulation of emamectin benzoate was found to cause long vertical lesions in the sapwood-phloem interface at each injection point.

  13. 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)

  14. Carabid Beetles as Parasitoids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The parasitoid habit is uncommon in beetles; only 11 beetle families include parasitoid species. Three tribes of 76 in the Carabidae are known to have species in which larvae are pupal ectoparasitoids: Brachinini, Peleciini, and Lebiini. The first larval instar is the free-living, host-finding stage...

  15. 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

  16. Effect of larval growth conditions on adult body mass and long-distance flight endurance in a wood-boring beetle: Do smaller beetles fly better?

    PubMed

    Brown, Stav; Soroker, Victoria; Ribak, Gal

    2017-02-22

    The tropical fig borer, Batocera rufomaculata De Geer, is a large beetle that is a pest on a number of fruit trees, including fig and mango. Adults feed on the leaves and twigs and females lay their eggs under the bark of the tree. The larvae bore into the tree trunk, causing substantial damage that may lead to the collapse and death of the host tree. We studied how larval development under inferior feeding conditions (experienced during development in dying trees) affects flight endurance in the adult insect. We grew larvae either in their natural host or on sawdust enriched with stale fig tree twigs. Flight endurance of the adults was measured using a custom-built flight-mill. Beetles emerging from the natural host were significantly larger but flew shorter distances than beetles reared on less favourable substrates. There was no difference in the allometric slope of wing area with body mass between the beetles groups; however flight muscle mass scaled with total body mass with an exponent significantly lower than 1.0. Hence, smaller beetles had proportionally larger flight muscles. These findings suggest that beetles that developed smaller as a result from poor nutritional conditions in deteriorating hosts, are better equipped to fly longer distances in search of a new host tree.

  17. Observation and modeling of polarized light from scarab beetles

    NASA Astrophysics Data System (ADS)

    Lowrey, Sam; de Silva, Lakshman; Hodgkinson, Ian; Leader, John

    2007-08-01

    The light reflected from scarab beetles illuminated with unpolarized white light is analyzed ellipsometrically and displayed as the sum of an elliptically polarized spectrum Ip and an unpolarized spectrum Iu. A chirped stack of chiral resonators, each with a characteristic Bragg wavelength and partial realignment of birefringent material to a fixed axis, is proposed as a model for simulation of both reflection and polarization spectra. Possible mechanisms that effectively eliminate impedance mismatch at the air-elytron interface and allow some beetles to exhibit nearly perfect circularly polarized reflections are discussed. Results are presented for three representative beetles, Ischiosopha bifasciata, which is shown to be a narrowband left-circular polarizer; Chrysophora chrysochlora, a broadband left-circular polarizer; and Chrysina woodi, an elliptical polarizer. The methods that are developed are applicable to the more general problem of synthesis of reflectors with prescribed reflection and polarization spectra.

  18. "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.

  19. Ethanolic extract of Boswellia ovalifoliolata bark and leaf attenuates doxorubicin-induced cardiotoxicity in mice.

    PubMed

    Uma Mahesh, Bandari; Shrivastava, Shweta; Kuncha, Madhusudhana; Sahu, Bidya Dhar; Swamy, Challa Veerabhadra; Pragada, Rajeswara Rao; Naidu, V G M; Sistla, Ramakrishna

    2013-11-01

    The aim of the study was to investigate the potential protective effect of ethanolic extract of Boswellia ovalifoliolata (BO) bark and leaf against doxorubicin (DOX)-induced cardiotoxicity in mice. Ethanolic extracts of BO bark (400 mg/kg) and leaves (250 mg/kg) were given orally to mice for 9 consecutive days and DOX (15 mg/kg; i.p.) was administered on the seventh day. Extract protected against DOX-induced ECG changes. It significantly inhibited DOX-provoked glutathione depletion and accumulation of malondialdehyde. The decrease in antioxidant enzyme activities of catalase, superoxide dismutase, glutathione peroxidase in cardiac tissue were significantly (p<0.05) mitigated after treatment with BO bark and leaf extracts. Pretreatment with BO significantly (p<0.05) restored the levels of DOX-induced rise of SGPT, SGOT, serum lactate dehydrogenase and creatine kinase-MB levels. These findings suggest that ethanolic extract of BO has protective effects against DOX-induced cardiotoxicity.

  20. Lumber recovery and deterioration of beetle-killed douglas-fir and grand fir in the Blue Mountains of eastern Oregon. Forest Service general technical report

    SciTech Connect

    Parry, D.L.; Filip, G.M.; Willits, S.A.; Parks, C.G.

    1996-09-01

    The purpose of this study was to determine the effect of time since death over a 4-year period on the amount of usable product volume and value, and to determine the species of fungi associated with wood deterioration in the stems of Douglas-fir and grand fir trees killed by bark beetles in northeastern Oregon.

  1. 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

  2. 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...

  3. Interactions between the yeast Ogataea pini and filamentous fungi associated with the western pine beetle.

    PubMed

    Davis, Thomas S; Hofstetter, Richard W; Foster, Jeffrey T; Foote, Nathaniel E; Keim, Paul

    2011-04-01

    Ecologically important microbes other than filamentous fungi can be housed within the fungal-transport structures (mycangia) of Dendroctonus bark beetles. The yeast Ogataea pini (Saccharomycetales: Saccharomycetaceae) was isolated from the mycangia of western pine beetle (Dendroctonus brevicomis) populations in northern Arizona (USA) with a frequency of 56%. We performed a series of in vitro assays to test whether volatile organic compounds produced by O. pini affected radial growth rates of mutualistic and antagonistic species of filamentous fungi that are commonly found in association with the beetle including Entomocorticium sp. B, Ophiostoma minus, Beauvaria bassiana, and an Aspergillus sp. We determined the compounds O. pini produced when grown on 2% malt extract agar using a gas chromatography/mass spectrometry (GC/MS) analysis of headspace volatiles. Volatiles produced by O. pini on artificial media significantly enhanced the growth of the mutualistic Entomocorticium sp. B, and inhibited growth of the entomopathogenic fungus B. bassiana. GC/MS revealed that O. pini produced ethanol, carbon disulfide (CS(2)), and Δ-3-carene in headspace. The results of these studies implicate O. pini as an important component in D. brevicomis community ecology, and we introduce multiple hypotheses for future tests of the effects of yeasts in the symbiont assemblages associated with Dendroctonus bark beetles.

  4. Genetic and genomic evidence of niche partitioning and adaptive radiation in mountain pine beetle fungal symbionts.

    PubMed

    Ojeda Alayon, Dario I; Tsui, Clement K M; Feau, Nicolas; Capron, Arnaud; Dhillon, Braham; Zhang, Yiyuan; Massoumi Alamouti, Sepideh; Boone, Celia K; Carroll, Allan L; Cooke, Janice E K; Roe, Amanda D; Sperling, Felix A H; Hamelin, Richard C

    2017-02-23

    Bark beetles form multipartite symbiotic associations with blue stain fungi (Ophiostomatales, Ascomycota). These fungal symbionts play an important role during the beetle's life cycle by providing nutritional supplementation, overcoming tree defences and modifying host tissues to favour brood development. The maintenance of stable multipartite symbioses with seemingly less competitive symbionts in similar habitats is of fundamental interest to ecology and evolution. We tested the hypothesis that the coexistence of three fungal species associated with the mountain pine beetle is the result of niche partitioning and adaptive radiation using SNP genotyping coupled with genotype-environment association analysis and phenotypic characterization of growth rate under different temperatures. We found that genetic variation and population structure within each species is best explained by distinct spatial and environmental variables. We observed both common (temperature seasonality and the host species) and distinct (drought, cold stress, precipitation) environmental and spatial factors that shaped the genomes of these fungi resulting in contrasting outcomes. Phenotypic intraspecific variations in Grosmannia clavigera and Leptographium longiclavatum, together with high heritability, suggest potential for adaptive selection in these species. By contrast, Ophiostoma montium displayed narrower intraspecific variation but greater tolerance to extreme high temperatures. Our study highlights unique phenotypic and genotypic characteristics in these symbionts that are consistent with our hypothesis. By maintaining this multipartite relationship, the bark beetles have a greater likelihood of obtaining the benefits afforded by the fungi and reduce the risk of being left aposymbiotic. Complementarity among species could facilitate colonization of new habitats and survival under adverse conditions.

  5. CXCL10/IP-10

    PubMed Central

    Gotsch, Francesca; Romero, Roberto; Friel, Lara; Kusanovic, Juan Pedro; Espinoza, Jimmy; Erez, Offer; Than, Nandor Gabor; Mittal, Pooja; Edwin, Samuel; Yoon, Bo Hyun; Kim, Chong Jai; Mazaki-Tovi, Shali; Chaiworapongsa, Tinnakorn; Hassan, Sonia S.

    2008-01-01

    OBJECTIVE Interferon (IFN)-γ inducible protein, CXCL10/IP-10, is a member of the CXC chemokine family with pro-inflammatory and anti-angiogenic properties. This chemokine has been proposed to be a key link between inflammation and angiogenesis. The aim of this study was to determine whether preeclampsia and delivery of a small for gestational age (SGA) neonate are associated with changes in maternal serum concentration of CXCL10/IP-10. STUDY DESIGN This cross-sectional study included patients in the following groups: (1) non pregnant women (N=49); (2) women with normal pregnancies (N=89); (3) patients with preeclampsia (N=100); and (4) patients who delivered an SGA neonate (N=78). SGA was defined as birth weight below the 10th percentile. Maternal serum concentrations of CXCL10/IP-10 were measured by sensitive immunoassay. Non-parametric statistics were used for analysis. RESULTS (1) Patients with normal pregnancies had a significantly higher median serum concentration of CXCL10/IP-10 than non-pregnant women (median: 116.1 pg/mL, range: 40.7-1314.3 vs. median: 90.3 pg/mL, range: 49.2-214.7, respectively; p=0.002); (2) no significant correlation was found between maternal serum concentration of CXCL10/IP-10 and gestational age (between 19 and 38 weeks); (3) there were no differences in median serum CXCL10/IP-10 concentrations between patients who delivered an SGA neonate and those with normal pregnancies (median: 122.4 pg/mL, range: 37.3-693.5 vs. median: 116.1 pg/mL, range: 40.7-1314.3, respectively; p>0.05); (4) patients with preeclampsia had a higher median serum concentration of CXCL10/IP-10 than normal pregnant women (median: 156.4 pg/mL, range: 47.4-645.9 vs. median: 116.1 pg/mL, range: 40.7-1314.3, respectively; p<0.05); (5) patients with preeclampsia had a higher median concentration of CXCL10/IP-10 than those who delivered an SGA neonate (median: 156.4 pg/mL, range: 47.4-645.9 vs. median: 122.4 pg/mL, range: 37.3-693.5, respectively; p<0.05). CONCLUSIONS

  6. Pesticide treatments affect mountain pine beetle abundance and woodpecker foraging behavior.

    PubMed

    Morrissey, Christy A; Dods, Patti L; Elliott, John E

    2008-01-01

    In British Columbia, Canada, management efforts used to control mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have included treatment of infested trees with an organic arsenic pesticide, monosodium methanearsonate (MSMA). Cumulative pesticide applications over a large geographic area have generated concerns about arsenic loading in the environment and potential toxicity to nontarget wildlife. We investigated woodpecker foraging patterns in infested stands with and without MSMA treatment using a combination of tree debarking indices, point count surveys, and radiotelemetry methods in addition to insect flight traps to measure mountain pine beetle emergence. Debarking indices indicated woodpecker foraging of MSMA-treated trees was significantly lower than nontreated trees in all sampling years. However, approximately 40% of MSMA trees had some evidence of foraging. Focal observations of foraging woodpeckers and point count surveys in MSMA treatment areas further confirmed that several species of woodpeckers regularly used MSMA stands during the breeding season. Radio-tagged Hairy (Picoides villosus) and Three-toed (Picoides dorsalis) Woodpeckers spent on average 13% and 23% (range 0-66%) of their time, respectively, in treated stands, despite the fact that these areas only comprised on average 1-2% of their core home range (1 km2). MSMA strongly reduced the emergence of several bark beetle (Coleoptera, Scolytidae) species including the mountain pine beetle, and there was a highly significant positive relationship between Dendroctonus beetle abundance and Three-toed Woodpecker abundance. This study identifies the potential negative impact that forest management practices using pesticides can have on woodpecker populations that depend on bark beetles and their host trees.

  7. Effects of postfire salvage logging on deadwood-associated beetles.

    PubMed

    Cobb, T P; Morissette, J L; Jacobs, J M; Koivula, M J; Spence, J R; Langor, D W

    2011-02-01

    In Canada and the United States pressure to recoup financial costs of wildfire by harvesting burned timber is increasing, despite insufficient understanding of the ecological consequences of postfire salvage logging. We compared the species richness and composition of deadwood-associated beetle assemblages among undisturbed, recently burned, logged, and salvage-logged, boreal, mixed-wood stands. Species richness was lowest in salvage-logged stands, largely due to a negative effect of harvesting on the occurrence of wood- and bark-boring species. In comparison with undisturbed stands, the combination of wildfire and logging in salvage-logged stands had a greater effect on species composition than either disturbance alone. Strong differences in species composition among stand treatments were linked to differences in quantity and quality (e.g., decay stage) of coarse woody debris. We found that the effects of wildfire and logging on deadwood-associated beetles were synergistic, such that the effects of postfire salvage logging could not be predicted reliably on the basis of data on either disturbance alone. Thus, increases in salvage logging of burned forests may have serious negative consequences for deadwood-associated beetles and their ecological functions in early postfire successional forests.

  8. 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.

  9. Beetles, Biofuel, and Coffee

    ScienceCinema

    Ceja-Navarro, Javier

    2016-07-12

    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.

  10. 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)

  11. 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.

  12. 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.

  13. CANOPEN Controller IP Core

    NASA Astrophysics Data System (ADS)

    Caramia, Maurizio; Montagna, Mario; Furano, Gianluca; Winton, Alistair

    2010-08-01

    This paper will describe the activities performed by Thales Alenia Space Italia supported by the European Space Agency in the definition of a CAN bus interface to be used on Exomars. The final goal of this activity is the development of an IP core, to be used in a slave node, able to manage both the CAN bus Data Link and Application Layer totally in hardware. The activity has been focused on the needs of the EXOMARS mission where devices with different computational performances are all managed by the onboard computer through the CAN bus.

  14. Lack of nucleotide variability in a beetle pest with extreme inbreeding.

    PubMed

    Andreev, D; Breilid, H; Kirkendall, L; Brun, L O; ffrench-Constant, R H

    1998-05-01

    The coffee berry borer beetle Hypothenemus hampei (Ferrari) (Curculionidae: Scolytinae) is the major insect pest of coffee and has spread to most of the coffee-growing countries of the world. This beetle also displays an unusual life cycle, with regular sibling mating. This regular inbreeding and the population bottlenecks occurring on colonization of new regions should lead to low levels of genetic diversity. We were therefore interested in determining the level of nucleotide variation in nuclear and mitochondrial genomes of this beetle worldwide. Here we show that two nuclear loci (Resistance to dieldrin and ITS2) are completely invariant, whereas some variability is maintained at a mitochondrial locus (COI), probably corresponding to a higher mutation rate in the mitochondrial genome. Phylogenetic analysis of the mitochondrial data shows only two clades of beetle haplotypes outside of Kenya, the proposed origin of the species. These data confirm that inbreeding greatly reduces nucleotide variation and suggest the recent global spread of only two inbreeding lines of this bark beetle.

  15. Area burned in the western United States is unaffected by recent mountain pine beetle outbreaks

    PubMed Central

    Hart, Sarah J.; Schoennagel, Tania; Veblen, Thomas T.; Chapman, Teresa B.

    2015-01-01

    In the western United States, mountain pine beetles (MPBs) have killed pine trees across 71,000 km2 of forest since the mid-1990s, leading to widespread concern that abundant dead fuels may increase area burned and exacerbate fire behavior. Although stand-level fire behavior models suggest that bark beetle-induced tree mortality increases flammability of stands by changing canopy and forest floor fuels, the actual effect of an MPB outbreak on subsequent wildfire activity remains widely debated. To address this knowledge gap, we superimposed areas burned on areas infested by MPBs for the three peak years of wildfire activity since 2002 across the western United States. Here, we show that the observed effect of MPB infestation on the area burned in years of extreme fire appears negligible at broad spatial extents. Contrary to the expectation of increased wildfire activity in recently infested red-stage stands, we found no difference between observed area and expected area burned in red-stage or subsequent gray-stage stands during three peak years of wildfire activity, which account for 46% of area burned during the 2002–2013 period. Although MPB infestation and fire activity both independently increased in conjunction with recent warming, our results demonstrate that the annual area burned in the western United States has not increased in direct response to bark beetle activity. Therefore, policy discussions should focus on societal adaptation to the effects of recent increases in wildfire activity related to increased drought severity. PMID:25831541

  16. 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

  17. Simulating stand-level water and carbon fluxes in beetle-attacked conifer forests in the Western U.S

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    In recent decades, forest mortality due to bark beetle infestation in conifer forests of western North America has reached epidemic levels, which may have profound effects on both present and future water and carbon cycling. The responses of evaporation, transpiration, and net photosynthesis to changing climate and disturbance are a major concern as they control the carbon balance of forests and the hydrologic cycle in a region that relies on water from montane and subalpine forest systems. Tree mortality during bark beetle infestation in this region is due to hydraulic failure resulting from fungal infection spread by the beetles. We modified the terrestrial regional ecosystem exchange simulator (TREES) model to incorporate xylem-occlusion effects on hydraulic conductance to simulate beetle attack over the period 2005-2012 in a subalpine conifer forest at the Glacier Lakes Ecosystem Experiment Site (GLEES) and over 2008-2012 at a lodgepole pine dominated site in southeast Wyoming. Model simulations with and without beetle effects were compared to eddy-covariance and sap-flux data measured at the sites. The simulations were run at a 30-minute time step and covered the pre- to post-beetle infestation period. Simulated NEE at GLEES ranged from 200 to -625 g C m-2 yr-1, annual ET ranged from 250 to 800 mm yr-1 over the seven years and standard error in predicted half-hourly NEE was <3 μmol CO2 m-2 s-1 and <2e-05 mm s-1 for ET. The stand transitioned from a C sink to C source during the beetle attack and our modified model captured this dynamic, while simulations without the beetle effect did not (i.e. continued C sink). However, simulated NEE was underestimated compared to flux data later in the infestation period (2011) by over 100 g C m-2 yr-1. ET decreased during beetle attack in both the observed and simulated data, but the modified model underestimated ET in the later phase of attack (2010-2011). These results suggest that ET and NEE in these conifer forests may

  18. Effects of Extensive Beetle-Induced Forest Mortality on Aromatic Organic Carbon Loading and Disinfection Byproduct Formation Potential

    NASA Astrophysics Data System (ADS)

    Brouillard, B.; Mikkelson, K. M.; Dickenson, E.; Sharp, J.

    2015-12-01

    Recent drought and warmer temperatures associated with climate change have caused increased pest-induced forest mortality with impacts on biogeochemical and hydrologic processes. To better understand the seasonal impacts of bark beetle infestation on water quality, samples were collected regularly over two overlapping snow free seasons at surface water intakes of six water treatment facilities in the Rocky Mountain region of Colorado displaying varying levels of bark beetle infestation (high >40%, moderate 20-40%, and low <20%). Organic carbon concentrations were typically 3 to 6 times higher in waters sourced from high beetle-impacted watersheds compared to moderate and low impact watersheds, revealing elevated specific ultraviolet absorbance, fluorescence, and humic-like intensity indicative of elevated aromatic carbon signatures. Accordingly, an increase in disinfection byproduct (DBP) formation potential of 400 to 600% was quantified when contrasted with watersheds containing less tree mortality. Beetle impact exasperated seasonal increases in carbon loading and DBP formation potential following both runoff and precipitation events indicating windows when enhanced water treatment may be utilized by water providers in highly infested regions. Additionally, elevated carbon concentrations throughout the summer and fall along with peaks following precipitation events provide evidence of shifting hydrologic flow paths in areas experiencing high forest mortality from decreased tree water uptake and interception. Collectively, these results demonstrate the need for continued watershed protection and monitoring with a changing climate as the resultant perturbations can have adverse effects on biogeochemistry and water quality in heavily impacted areas.

  19. Volatile Hydrocarbon Pheromones from Beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This chapter reviews literature about hydrocarbons from beetles that serve as long-range pheromones. The most thoroughly studied beetles that use volatile hydrocarbon pheromones belong to the family Nitidulidae in the genera Carpophilus and Colopterus. Published pheromone research deals with behav...

  20. Bark functional ecology: evidence for tradeoffs, functional coordination, and environment producing bark diversity.

    PubMed

    Rosell, Julieta A; Gleason, Sean; Méndez-Alonzo, Rodrigo; Chang, Yvonne; Westoby, Mark

    2014-01-01

    The causes underlying bark diversity are unclear. Variation has been frequently attributed to environmental differences across sites. However, variation may also result from tradeoffs and coordination between bark's multiple functions. Bark traits may also covary with wood and leaf traits as part of major dimensions of plant variation. To assess hypotheses regarding tradeoffs and functional coordination, we measured bark traits reflecting protection, storage, mechanics, and photosynthesis in branches of 90 species spanning a wide phylogenetic and environmental range. We also tested associations between bark, wood, and leaf traits. We partitioned trait variation within species, and within and across communities to quantify variation associated with across-site differences. We observed associations between bark mechanics and storage, density and thickness, and thickness and photosynthetic activity. Increasing bark thickness contributed significantly to stiffer stems and greater water storage. Bark density, water content, and mechanics covaried strongly with the equivalent wood traits, and to a lesser degree with leaf size, xylem conductivity, and vessel diameter. Most variation was observed within sites and had low phylogenetic signal. Compared with relatively minor across-site differences, tradeoffs and coordination among functions of bark, leaves, and wood are likely to be major and overlooked factors shaping bark ecology and evolution.

  1. Identification of a major IP5 kinase in Cryptococcus neoformans confirms that PP-IP5/IP7, not IP6, is essential for virulence

    PubMed Central

    Li, Cecilia; Lev, Sophie; Saiardi, Adolfo; Desmarini, Desmarini; Sorrell, Tania C.; Djordjevic, Julianne T.

    2016-01-01

    Fungal inositol polyphosphate (IP) kinases catalyse phosphorylation of IP3 to inositol pyrophosphate, PP-IP5/IP7, which is essential for virulence of Cryptococcus neoformans. Cryptococcal Kcs1 converts IP6 to PP-IP5/IP7, but the kinase converting IP5 to IP6 is unknown. Deletion of a putative IP5 kinase-encoding gene (IPK1) alone (ipk1Δ), and in combination with KCS1 (ipk1Δkcs1Δ), profoundly reduced virulence in mice. However, deletion of KCS1 and IPK1 had a greater impact on virulence attenuation than that of IPK1 alone. ipk1Δkcs1Δ and kcs1Δ lung burdens were also lower than those of ipk1Δ. Unlike ipk1Δ, ipk1Δkcs1Δ and kcs1Δ failed to disseminate to the brain. IP profiling confirmed Ipk1 as the major IP5 kinase in C. neoformans: ipk1Δ produced no IP6 or PP-IP5/IP7 and, in contrast to ipk1Δkcs1Δ, accumulated IP5 and its pyrophosphorylated PP-IP4 derivative. Kcs1 is therefore a dual specificity (IP5 and IP6) kinase producing PP-IP4 and PP-IP5/IP7. All mutants were similarly attenuated in virulence phenotypes including laccase, urease and growth under oxidative/nitrosative stress. Alternative carbon source utilisation was also reduced significantly in all mutants except ipk1Δ, suggesting that PP-IP4 partially compensates for absent PP-IP5/IP7 in ipk1Δ grown under this condition. In conclusion, PP-IP5/IP7, not IP6, is essential for fungal virulence. PMID:27033523

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

    PubMed

    Lerch, Andrew P; Pfammatter, Jesse A; Bentz, Barbara J; Raffa, Kenneth F

    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.

  3. 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

  4. Photosynthetic bark: Use of chlorophyll absorption continuum index to estimate Boswellia papyrifera bark chlorophyll content

    NASA Astrophysics Data System (ADS)

    Girma, Atkilt; Skidmore, Andrew K.; de Bie, C. A. J. M.; Bongers, Frans; Schlerf, Martin

    2013-08-01

    Quantification of chlorophyll content provides useful insight into the physiological performance of plants. Several leaf chlorophyll estimation techniques, using hyperspectral instruments, are available. However, to our knowledge, a non-destructive bark chlorophyll estimation technique is not available. We set out to assess Boswellia papyrifera tree bark chlorophyll content and to provide an appropriate bark chlorophyll estimation technique using hyperspectral remote sensing techniques. In contrast to the leaves, the bark of B. papyrifera has several outer layers masking the inner photosynthetic bark layer. Thus, our interest includes understanding how much light energy is transmitted to the photosynthetic inner bark and to what extent the inner photosynthetic bark chlorophyll activity could be remotely sensed during both the wet and the dry season. In this study, chlorophyll estimation using the chlorophyll absorption continuum index (CACI) yielded a higher R2 (0.87) than others indices and methods, such as the use of single band, simple ratios, normalized differences, and conventional red edge position (REP) based estimation techniques. The chlorophyll absorption continuum index approach considers the increase or widening in area of the chlorophyll absorption region, attributed to high concentrations of chlorophyll causing spectral shifts in both the yellow and the red edge. During the wet season B. papyrifera trees contain more bark layers than during the dry season. Having less bark layers during the dry season (leaf off condition) is an advantage for the plants as then their inner photosynthetic bark is more exposed to light, enabling them to trap light energy. It is concluded that B. papyrifera bark chlorophyll content can be reliably estimated using the chlorophyll absorption continuum index analysis. Further research on the use of bark signatures is recommended, in order to discriminate the deciduous B. papyrifera from other species during the dry season.

  5. Phenolic glycosides of Paulownia tomentosa bark.

    PubMed

    Sticher, O; Lahloub, M F

    1982-11-01

    The isolation of acteoside and coniferin from Paulownia tomentosa bark along with the previously reported phenolic glucoside syringin is described. The structure of both, acteoside and coniferin, have been assigned by (1)H- and (13)C-NMR spectroscopy.

  6. Locating POPs Sources with Tree Bark.

    PubMed

    Peverly, Angela A; Salamova, Amina; Hites, Ronald A

    2015-12-01

    Locating sources of persistent organic pollutants (POPs) to the atmosphere can sometimes be difficult. We suggest that tree bark makes an excellent passive atmospheric sampler and that spatial analysis of tree bark POPs concentrations can often pinpoint their sources. This is an effective strategy because tree bark is lipophilic and readily adsorbs and collects POPs from the atmosphere. As such, tree bark is an ideal sampler to find POPs sources globally, regionally, or locally. This article summarizes some work on this subject with an emphasis on kriged maps and a simple power-law model, both of which have been used to locate sources. Three of the four examples led directly to the pollutant's manufacturing plant.

  7. Ethanol attracts scolytid beetles to Phytophthora ramorum cankers on coast live oak.

    PubMed

    Kelsey, Rick G; Beh, Maia M; Shaw, David C; Manter, Daniel K

    2013-04-01

    Ethanol in sapwood was analyzed along vertical transects, through small spot cankers and larger basal cankers, of Phytophthora ramorum-infected stems of Quercus agrifolia at three sites in California. Trees with large basal cankers, known to attract scolytid beetles, had a 4.3 times higher ethanol level than trees with spot cankers that attract fewer beetles. Ethanol concentrations inside cankers, where scolytid beetles preferentially attack, varied by about four orders of magnitude among samples, with a median level of 16.0 μg.g(-1) fresh mass. This concentration was 4.3 and 15.5 times greater, respectively, than the concentrations at 1 cm or 15-30 cm outside the canker boundaries. In the laboratory, we demonstrated that ethanol escaped through the bark of a Q. garryana log just 3 days after it was added to the sapwood. At the three study sites, traps baited with ethanol captured more Xyleborinus saxesenii, Pseudopityophthorus pubipennis, and Monarthrum dentiger (all Coleoptera: Curculionidae: Scolytinae) than traps baited with ethanol plus (-)-α-pinene, or ethanol plus 4-allylanisole (4AA). Logs of Q. agrifolia with a 50 % ethanol solution added to the sapwood were placed at the study sites, with or without additional bark treatments above the ethanol. The number of scolytid beetle gallery holes above the ethanol-infused sapwood was 4.4 times greater than that on the opposite side of the log where no ethanol was added. Attachment of ultra-high release (-)-α-pinene pouches to the bark surface above the 50 % ethanol solution reduced scolytid attacks to a density of 19.1 % that of logs without this treatment. We conclude that ethanol in P. ramorum cankers functions as a primary host attractant for scolytid beetles and is an important link in colonization of these cankers and accelerated mortality of Q. agrifolia. The results of this research shed light on the chemical ecology behind the focused scolytid attacks on P. ramorum-infected coast live oaks, and lay the

  8. 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.

  9. 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

  10. 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.

  11. New Insights into the Consequences of Post-Windthrow Salvage Logging Revealed by Functional Structure of Saproxylic Beetles Assemblages

    PubMed Central

    Thorn, Simon; Bässler, Claus; Gottschalk, Thomas; Hothorn, Torsten; Bussler, Heinz; Raffa, Kenneth; Müller, Jörg

    2014-01-01

    Windstorms, bark beetle outbreaks and fires are important natural disturbances in coniferous forests worldwide. Wind-thrown trees promote biodiversity and restoration within production forests, but also cause large economic losses due to bark beetle infestation and accelerated fungal decomposition. Such damaged trees are often removed by salvage logging, which leads to decreased biodiversity and thus increasingly evokes discussions between economists and ecologists about appropriate strategies. To reveal the reasons behind species loss after salvage logging, we used a functional approach based on four habitat-related ecological traits and focused on saproxylic beetles. We predicted that salvage logging would decrease functional diversity (measured as effect sizes of mean pairwise distances using null models) as well as mean values of beetle body size, wood diameter niche and canopy cover niche, but would increase decay stage niche. As expected, salvage logging caused a decrease in species richness, but led to an increase in functional diversity by altering the species composition from habitat-filtered assemblages toward random assemblages. Even though salvage logging removes tree trunks, the most negative effects were found for small and heliophilous species and for species specialized on wood of small diameter. Our results suggested that salvage logging disrupts the natural assembly process on windthrown trees and that negative ecological impacts are caused more by microclimate alteration of the dead-wood objects than by loss of resource amount. These insights underline the power of functional approaches to detect ecosystem responses to anthropogenic disturbance and form a basis for management decisions in conservation. To mitigate negative effects on saproxylic beetle diversity after windthrows, we recommend preserving single windthrown trees or at least their tops with exposed branches during salvage logging. Such an extension of the green-tree retention

  12. New insights into the consequences of post-windthrow salvage logging revealed by functional structure of saproxylic beetles assemblages.

    PubMed

    Thorn, Simon; Bässler, Claus; Gottschalk, Thomas; Hothorn, Torsten; Bussler, Heinz; Raffa, Kenneth; Müller, Jörg

    2014-01-01

    Windstorms, bark beetle outbreaks and fires are important natural disturbances in coniferous forests worldwide. Wind-thrown trees promote biodiversity and restoration within production forests, but also cause large economic losses due to bark beetle infestation and accelerated fungal decomposition. Such damaged trees are often removed by salvage logging, which leads to decreased biodiversity and thus increasingly evokes discussions between economists and ecologists about appropriate strategies. To reveal the reasons behind species loss after salvage logging, we used a functional approach based on four habitat-related ecological traits and focused on saproxylic beetles. We predicted that salvage logging would decrease functional diversity (measured as effect sizes of mean pairwise distances using null models) as well as mean values of beetle body size, wood diameter niche and canopy cover niche, but would increase decay stage niche. As expected, salvage logging caused a decrease in species richness, but led to an increase in functional diversity by altering the species composition from habitat-filtered assemblages toward random assemblages. Even though salvage logging removes tree trunks, the most negative effects were found for small and heliophilous species and for species specialized on wood of small diameter. Our results suggested that salvage logging disrupts the natural assembly process on windthrown trees and that negative ecological impacts are caused more by microclimate alteration of the dead-wood objects than by loss of resource amount. These insights underline the power of functional approaches to detect ecosystem responses to anthropogenic disturbance and form a basis for management decisions in conservation. To mitigate negative effects on saproxylic beetle diversity after windthrows, we recommend preserving single windthrown trees or at least their tops with exposed branches during salvage logging. Such an extension of the green-tree retention

  13. Quantum non-barking dogs

    NASA Astrophysics Data System (ADS)

    Imari Walker, Sara; Davies, Paul C. W.; Samantray, Prasant; Aharonov, Yakir

    2014-06-01

    Quantum weak measurements with states both pre- and post-selected offer a window into a hitherto neglected sector of quantum mechanics. A class of such systems involves time dependent evolution with transitions possible. In this paper we explore two very simple systems in this class. The first is a toy model representing the decay of an excited atom. The second is the tunneling of a particle through a barrier. The post-selection criteria are chosen as follows: at the final time, the atom remains in its initial excited state for the first example and the particle remains behind the barrier for the second. We then ask what weak values are predicted in the physical environment of the atom (to which no net energy has been transferred) and in the region beyond the barrier (to which the particle has not tunneled). Thus, just as the dog that didn't bark in Arthur Conan Doyle's story Silver Blaze gave Sherlock Holmes meaningful information about the dog's non-canine environment, here we probe whether the particle that has not decayed or has not tunneled can provide measurable information about physical changes in the environment. Previous work suggests that very large weak values might arise in these regions for long durations between pre- and post-selection times. Our calculations reveal some distinct differences between the two model systems.

  14. An Automated Instrument for the Measurement of Bark Microrelief

    NASA Astrophysics Data System (ADS)

    van Stan, J. T.; Jarvis, M.; Levia, D. F.

    2009-05-01

    Bark microrelief is of importance to the physiological ecology of forested ecosystems because it has been documented to influence the distribution of corticolous lichens, stemflow generation, and forest biogeochemical cycles. Hitherto no instrument existed to characterize the inherent variability of bark microrelief with high spatial resolution. Our newly-designed bark microrelief instrument, the LaserBarkTM, consists of a hinged ring, laser rangefinder, and motor linked to a standard laptop. The LaserBarkTM produces trunk cross- sections at a 0.33 degree horizontal resolution and detects bark ridge-to furrow heights at < 1 mm resolution. The LaserBarkTM was validated by comparing measurements of bark microrelief between the instrument and digital calipers. The mean absolute error of the instrument was 0.83 mm. Our bark microrelief instrument can supply critical requisite information of bark microstructure that be used by researchers to interpret the distribution of lichens and bryophytes on tree surfaces, relate stemflow yield and chemistry to bark microrelief, and provide detailed measurements of the changes of bark microrelief with stem dehydration. In short, the LaserBarkTM can be used to gain a more holistic understanding of the functional ecology of forest ecosystems.

  15. 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

  16. 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

  17. Climate and weather influences on spatial temporal patterns of mountain pine beetle populations in Washington and Oregon.

    PubMed

    Preisler, Haiganoush K; Hicke, Jeffrey A; Ager, Alan A; Hayes, Jane L

    2012-11-01

    Widespread outbreaks of mountain pine beetle in North America have drawn the attention of scientists, forest managers, and the public. There is strong evidence that climate change has contributed to the extent and severity of recent outbreaks. Scientists are interested in quantifying relationships between bark beetle population dynamics and trends in climate. Process models that simulate climate suitability for mountain pine beetle outbreaks have advanced our understanding of beetle population dynamics; however, there are few studies that have assessed their accuracy across multiple outbreaks or at larger spatial scales. This study used the observed number of trees killed by mountain pine beetles per square kilometer in Oregon and Washington, USA, over the past three decades to quantify and assess the influence of climate and weather variables on beetle activity over longer time periods and larger scales than previously studied. Influences of temperature and precipitation in addition to process model output variables were assessed at annual and climatological time scales. The statistical analysis showed that new attacks are more likely to occur at locations with climatological mean August temperatures >15 degrees C. After controlling for beetle pressure, the variables with the largest effect on the odds of an outbreak exceeding a certain size were minimum winter temperature (positive relationship) and drought conditions in current and previous years. Precipitation levels in the year prior to the outbreak had a positive effect, possibly an indication of the influence of this driver on brood size. Two-year cumulative precipitation had a negative effect, a possible indication of the influence of drought on tree stress. Among the process model variables, cold tolerance was the strongest indicator of an outbreak increasing to epidemic size. A weather suitability index developed from the regression analysis indicated a 2.5x increase in the odds of outbreak at locations

  18. 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

  19. 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.

  20. Running TCP/IP over ATM Networks.

    ERIC Educational Resources Information Center

    Witt, Michael

    1995-01-01

    Discusses Internet protocol (IP) and subnets and describes how IP may operate over asynchronous transfer mode (ATM). Topics include TCP (transmission control protocol), ATM cells and adaptation layers, a basic architectural model for IP over ATM, address resolution, mapping IP to a subnet technology, and connection management strategy. (LRW)

  1. Geosmithia morbida sp. nov., a new phytopathogenic species living in symbiosis with the walnut twig beetle (Pityophthorus juglandis) on Juglans in USA.

    PubMed

    Kolarík, Miroslav; Freeland, Emily; Utley, Curtis; Tisserat, Ned

    2011-01-01

    Widespread morbidity and mortality of Juglans nigra has occurred in the western USA over the past decade. Tree mortality is the result of aggressive feeding by the walnut twig beetle (Pityophthorus juglandis) and subsequent canker development around beetle galleries caused by a filamentous ascomycete in genus Geosmithia (Ascomycota: Hypocreales). Thirty-seven Geosmithia strains collected from J. californica, J. hindsii, J. major and J. nigra in seven USA states (AZ, CA, CO, ID, OR, UT, WA) were compared with morphological and molecular methods (ITS rDNA sequences). Strains had common characteristics including yellowish conidia en masse, growth at 37 C and absence of growth on Czapek-Dox agar and belonged to a single species described here as G. morbida. Whereas Geosmithia are common saprobes associated with bark beetles attacking hardwoods and conifers worldwide, G. morbida is the first species documented as a plant pathogen.

  2. Dynamic IP Reputation from DNS

    DTIC Science & Technology

    2016-06-21

    Dynamic IP Reputation from DNS Manos Antonakakis, Roberto Perdisci, and Wenke Lee Georgia Institute of Technology Report Documentation Page Form...Institute of Technology ,College of Computing,Atlanta,GA,30332 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS

  3. Continuously Connected With Mobile IP

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Cisco Systems developed Cisco Mobile Networks, making IP devices mobile. With this innovation, a Cisco router and its connected IP devices can roam across network boundaries and connection types. Because a mobile user is able to keep the same IP address while roaming, a live IP connection can be maintained without interruption. Glenn Research Center jointly tested the technology with Cisco, and is working to use it on low-earth-orbiting research craft. With Cisco's Mobile Networks functionality now available in Cisco IOS Software release 12.2(4)T, the commercial advantages and benefits are numerous. The technology can be applied to public safety, military/homeland security, emergency management services, railroad and shipping systems, and the automotive industry. It will allow ambulances, police, firemen, and the U.S. Coast Guard to stay connected to their networks while on the move. In the wireless battlefield, the technology will provide rapid infrastructure deployment for U.S. national defense. Airline, train, and cruise passengers utilizing Cisco Mobile Networks can fly all around the world with a continuous Internet connection. Cisco IOS(R) Software is a registered trademark of Cisco Systems.

  4. 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.

  5. Large Shift in Symbiont Assemblage in the Invasive Red Turpentine Beetle

    PubMed Central

    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. PMID:24205124

  6. 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

  7. 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.

  8. Metals bioaccumulation mechanism in neem bark

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this work was to define the bioaccumulation mechanism of metals onto the non-living biomaterial prepared from an extensively available plant bark biomass of neem (Azadirachta indica). Based on maximum ultimate fixation capacities (mmol/g) of the product, metals ions could be arranged as H...

  9. Constituents from the bark of Tabebuia impetiginosa.

    PubMed

    Warashina, Tsutomu; Nagatani, Yoshimi; Noro, Tadataka

    2006-01-01

    Thirteen new phenolic glycosides were obtained by further study of constituents from the bark of Tabebuia impetiginosa (MART. ex DC) Standley (Bignoniaceae). The structures of these compounds were determined based on NMR, mass spectral and chemical evidence. Most of them have a glycosyl unit esterified by a benzoic acid derivative.

  10. Amending pine bark with alternative substrates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Due to a number of factors, pine bark supplies have significantly decreased over the past few years. While alternative substrates are being evaluated, many growers are asking if these alternative substrates can be used to stretch existing PB supplies. In this study, two alternative substrates, “Cl...

  11. 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.

  12. 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.

  13. 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.

  14. Standardization efforts in IP telephony

    NASA Astrophysics Data System (ADS)

    Sengodan, Senthil; Bansal, Raj

    1999-11-01

    The recent interest in IP telephony has led to a tremendous increase of standardization activities in the area. The three main standards bodies in the area of IP telephony are the International Telecommunication Union's (ITU-T) Study Group (SG) 16, the Internet Engineering Task Force (IETF) and the European Telecommunication Standards Institute's (ETSI) TIPHON project. In addition, forums such as the International Multimedia Teleconferencing Consortium (IMTC), the Intelligent Network Forum (INF), the International Softswitch Consortium (ISC), the Electronic Computer Telephony Forum (ECTF), and the MIT's Internet Telephony Consortium (ITC) are looking into various other aspects that aim at the growth of this industry. This paper describes the main tasks (completed and in progress) undertaken by these organizations. In describing such work, an overview of the underlying technology is also provided.

  15. OSI and TCP/IP

    NASA Technical Reports Server (NTRS)

    Randolph, Lynwood P.

    1994-01-01

    The Open Systems Interconnection Transmission Control Protocol/Internet Protocol (OSI TCP/IP) and the Government Open Systems Interconnection Profile (GOSIP) are compared and described in terms of Federal internetworking. The organization and functions of the Federal Internetworking Requirements Panel (FIRP) are discussed and the panel's conclusions and recommendations with respect to the standards and implementation of the National Information Infrastructure (NII) are presented.

  16. 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…

  17. [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.

  18. 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

  19. 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.

  20. Relative importance of climate and mountain pine beetle outbreaks on the occurrence of large wildfires in the western USA.

    PubMed

    Mietkiewicz, Nathan; Kulakowski, Dominik

    2016-12-01

    Extensive outbreaks of bark beetles have killed trees across millions of hectares of forests and woodlands in western North America. These outbreaks have led to spirited scientific, public, and policy debates about consequential increases in fire risk, especially in the wildland-urban interface (WUI), where homes and communities are at particular risk from wildfires. At the same time, large wildfires have become more frequent across this region. Widespread expectations that outbreaks increase extent, severity, and/or frequency of wildfires are based partly on visible and dramatic changes in foliar moisture content and other fuel properties following outbreaks, as well as associated modeling projections. A competing explanation is that increasing wildfires are driven primarily by climatic extremes, which are becoming more common with climate change. However, the relative importance of bark beetle outbreaks vs. climate on fire occurrence has not been empirically examined across very large areas and remains poorly understood. The most extensive outbreaks of tree-killing insects across the western United States have been of mountain pine beetle (MPB; Dendroctonus ponderosae), which have killed trees over >650,000 km(2) , mostly in forests dominated by lodgepole pine (Pinus contorta). We show that outbreaks of MPB in lodgepole pine forests of the western United States have been less important than climatic variability for the occurrence of large fires over the past 29 years. In lodgepole pine forests in general, as well as those in the WUI, occurrence of large fires was determined primarily by current and antecedent high temperatures and low precipitation but was unaffected by preceding outbreaks. Trends of increasing co-occurrence of wildfires and outbreaks are due to a common climatic driver rather than interactions between these disturbances. Reducing wildfire risk hinges on addressing the underlying climatic drivers rather than treating beetle-affected forests.

  1. A preliminary pharmacokinetic study of betulin, the main pentacyclic triterpene from extract of outer bark of birch (Betulae alba cortex).

    PubMed

    Jäger, Sebastian; Laszczyk, Melanie N; Scheffler, Armin

    2008-12-18

    During the last two decades triterpenes have attracted attention because of their pharmacological potential. Triterpene extract (TE) from outer bark of birch consisting mainly of betulin is able to form an oleogel which was successfully tested in the treatment of actinic keratosis. Some aspects of TE in vitro pharmacology are already known. Now we show preliminary pharmacokinetics of betulin and results of a subchronic toxicity study of TE in rats and dogs. Because of poor aqueous solubility of the TE-triterpenes (< 0.1 microg/mL respectively), for pharmacokinetic studies it was suspended in sesame oil (rats, i.p.) and PEG 400 / 0.9 % NaCl (dogs, s.c.). I.p. administered, betulin, the main component of TE, shows time dependency over a period of 4 h and reaches a dose-independent serum level of 0.13 microg/mL. Dose dependency was observed with s.c. administration. At 300 mg/kg a maximum plasma concentration of 0.33 microg/mL betulin was detected after 28 daily applications. The subchronic toxicity study showed no toxicity of TE in rats (i.p.) and dogs (s.c.). In conclusion, triterpene extract from birch bark is safe, its betulin is bioavailable and in addition to published triterpene biological activities TE provides high potential for further pharmaceutical and pharmacological research.

  2. VoIP in a Campus Environment

    ERIC Educational Resources Information Center

    Young, Dan

    2005-01-01

    Internet Protocol (IP) Telephony, or voice-over IP (VoIP), has proved to be a wise decision for many organizations. This technology crosses the boundaries of public and private networks, enterprise and residential markets, voice and data technologies, as well as local and long-distance services. The convergence of voice and data into a single,…

  3. Visualizing the mesothoracic spiracles in a bark beetle: The coffee berry borer, Hypothenemus hampei

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In a low-temperature scanning electron microscopy study aimed at determining whether the coffee berry borer (Hypothenemus hampei (Ferrari); Coleoptera: Curculionidae: Scolytinae) possesses mycangia, we fortuitously detected the mesothoracic spiracles, which are usually concealed. The mesothoracic s...

  4. Phylogeography of the bark beetle Dendroctonus mexicanus Hopkins (Coleoptera: Curculionidae: Scolytinae).

    PubMed

    Anducho-Reyes, Miguel A; Cognato, Anthony I; Hayes, Jane L; Zúñiga, Gerardo

    2008-12-01

    Dendroctonus mexicanus is polyphagous within the Pinus genus and has a wide geographical distribution in Mexico and Guatemala. We examined the pattern of genetic variation across the range of this species to explore its demographic history and its phylogeographic pattern. Analysis of the mtDNA sequences of 173 individuals from 25 Mexican populations allowed to us identify 53 geographically structured haplotypes. High haplotype and low nucleotide diversities and Tajima's D indicate that D. mexicanus experienced rapid population expansion during its dispersal across mountain systems within its current range. The nested clade phylogeographic analysis indicates that the phylogeographic pattern of D. mexicanus is explained by continuous dispersion among lineages from the Sierra Madre Occidental, the Sierra Madre Oriental and the Trans-Mexican Volcanic Belt. However, we also observed isolation events among haplotypes from the Cofre de Perote/Trans-Mexican Volcanic Belt/Sierra Madre Oriental and the Trans-Mexican Volcanic Belt/Sierra Madre del Sur, which is consistent with the present conformation of mountain systems in Mexico and the emergence of geographical barriers during the Pleistocene.

  5. Separation of hydrocarbons and lipid from water using treated bark.

    PubMed

    Haussard, M; Gaballah, I; Kanari, N; de Donato, Ph; Barrès, O; Villieras, F

    2003-01-01

    This paper explores the possibility of using treated bark to remove oily compounds from water. Bark was first biologically or chemically treated and saturated with transition metal ions (TMI) to avoid the release of soluble organic compounds from the bark in the treated effluents. Several experimental parameters affecting the oil removal efficiency (RE) were studied (initial oil concentration, temperature, time, etc.). Saturated bark was characterized using Fourier transform infrared (FTIR) spectroscopy and bark wetting index was determined. Results of the retention of lipids suggested that their removal could exceed 95% of initial oil concentration. The uptake of lipid by treated bark varied from 0.2 to 2.0 g of organic oil/g of dry sorbent. No significant chemical modifications of saturated bark were observed in infrared spectroscopy after the sorption of oleic acid on bark treated with transition metal ions. The structure of adsorbed tridimensional layer of oleic acid molecules seemed to take place through the double bond. The hydrocarbon RE exceeded 95% using oil-water mixture with a hydrocarbon/bark ratio of one. The sorption reaction of hydrocarbons and lipids was quasi-instantaneous and seemed to be influenced by the temperature. This indicated that the retention mechanism was related to the capillary action. Results of FTIR spectroscopy suggested that no chemical bonds between barks and oily compounds were established.

  6. Early Cretaceous angiosperms and beetle evolution.

    PubMed

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

    2013-09-12

    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.

  7. 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.

  8. Climate Change Effects on Multiple Disturbance Interactions: Wildland Fire, Mountain Pine Beetles, and Blister Rust Simulations on a Yellowstone National Park Landscape

    NASA Astrophysics Data System (ADS)

    Keane, R. E.; Loehman, R.; Smithwick, E. A.

    2011-12-01

    Complex interactions between disturbance, climate, and vegetation will dramatically alter spatial patterns and ecosystem processes in the future, but the interactions between multiple disturbances may ultimately determine vegetation response and landscape dynamics. The frequency and extent of wildland fire, mountain pine beetles, and blister rust are predicted to increase with global warming, but the interactions and reciprocal feedbacks between these three disturbances could also alter landscape trajectories. We used the mechanistic, spatially explicit, landscape FireBGCv2 model parameterized for Yellowstone National Park to determine the extent to which climate altered ecosystem carbon storage, landscape composition and structure, and interacting disturbance regimes that include wildland fire, mountain pine beetles, and white pine blister rust for lodgepole and whitebark pine forests. Under two simulated future climate scenarios (B2 and A2) and three disturbance scenarios (fire only, fire and beetles/rust, beetles/rust only), it appears fire and bark beetle disturbance events interacted to moderate burn area and decrease insect/disease mortality. Landscape composition and structure was roughly the same across disturbance scenarios except whitebark pine disappears when rust is present in the simulation. Overall, we conclude that disturbance interactions are important to landscape dynamics under future climates and these interactions may overwhelm the direct effects of climate or single disturbances.

  9. Mobile-ip Aeronautical Network Simulation Study

    NASA Technical Reports Server (NTRS)

    Ivancic, William D.; Tran, Diepchi T.

    2001-01-01

    NASA is interested in applying mobile Internet protocol (mobile-ip) technologies to its space and aeronautics programs. In particular, mobile-ip will play a major role in the Advanced Aeronautic Transportation Technology (AATT), the Weather Information Communication (WINCOMM), and the Small Aircraft Transportation System (SATS) aeronautics programs. This report presents the results of a simulation study of mobile-ip for an aeronautical network. The study was performed to determine the performance of the transmission control protocol (TCP) in a mobile-ip environment and to gain an understanding of how long delays, handoffs, and noisy channels affect mobile-ip performance.

  10. Challenges Regarding IP Core Functional Reliability

    NASA Technical Reports Server (NTRS)

    Berg, Melanie D.; LaBel, Kenneth A.

    2017-01-01

    For many years, intellectual property (IP) cores have been incorporated into field programmable gate array (FPGA) and application specific integrated circuit (ASIC) design flows. However, the usage of large complex IP cores were limited within products that required a high level of reliability. This is no longer the case. IP core insertion has become mainstream including their use in highly reliable products. Due to limited visibility and control, challenges exist when using IP cores and subsequently compromise product reliability. We discuss challenges and suggest potential solutions to critical application IP insertion.

  11. Hepatoprotective properties of Bauhinia variegata bark extract.

    PubMed

    Bodakhe, Surendra H; Ram, Alpana

    2007-09-01

    Bauhinia variegata (Leguminosae) commonly known as Kachnar, is widely used in Ayurveda as tonic to the liver. The present work was carried out to assess the potential of Bauhinia variegata bark as hepatoprotective agent. The hepatoprotective activity was investigated in carbon tetrachloride (CCl(4)) intoxicated Sprague-Dawley rats. Bauhinia variegata alcoholic Stem Bark Extract (SBE) at different doses (100 and 200 mg/kg) were administered orally to male Sprague-Dawley rats weighing between 100-120 g. The effect of SBE on the serum marker enzymes, viz., AST, ALT, ALP and GGT and liver protein and lipids were assessed. The extract exhibited significant hepatoprotective activity. Hence, B. variegata appears to be a promising hepatoprotective agent.

  12. IP Profiling via Service Cluster Membership Vectors

    SciTech Connect

    Bartoletti, A

    2009-02-23

    This study investigates the feasibility of establishing and maintaining a system of compact IP behavioral profiles as a robust means of computer anomaly definition and detection. These profiles are based upon the degree to which a system's (IP's) network traffic is distributed among stable characteristic clusters derived of the aggregate session traffic generated by each of the major network services. In short, an IP's profile represents its degree of membership in these derived service clusters. The goal is to quantify and rank behaviors that are outside of the statistical norm for the services in question, or present significant deviation from profile for individual client IPs. Herein, we establish stable clusters for accessible features of common session traffic, migrate these clusters over time, define IP behavior profiles with respect to these clusters, migrate individual IP profiles over time, and demonstrate the detection of IP behavioral changes in terms of deviation from profile.

  13. Assessment of beetle diversity, community composition and potential threats to forestry using kairomone-baited traps.

    PubMed

    Olivier-Espejel, S; Hurley, B P; Garnas, J

    2017-02-01

    Traps designed to capture insects during normal movement/dispersal, or via attraction to non-specific (plant) volatile lures, yield by-catch that carries valuable information about patterns of community diversity and composition. In order to identify potential native/introduced pests and detect predictors of colonization of non-native pines, we examined beetle assemblages captured in intercept panel traps baited with kairomone lures used during a national monitoring of the woodwasp, Sirex noctilio, in Southern Africa. We identified 50 families and 436 morphospecies of beetles from nine sites sampled in both 2008 and 2009 and six areas in 2007 (trap catch pooled by region) across a latitudinal and elevational gradient. The most diverse groups were mainly those strongly associated with trees, known to include damaging pests. While native species dominated the samples in terms of richness, the dominant species was the introduced bark beetle Orthotomicus erosus (Curculionidae: Scolytinae) (22 ± 34 individuals/site). Four Scolytinae species without previous records in South Africa, namely Coccotrypes niger, Hypocryphalus robustus (formerly Hypocryphalus mangiferae), Hypothenemus birmanus and Xyleborus perforans, were captured in low abundances. Communities showed temporal stability within sites and strong biogeographic patterns across the landscape. The strongest single predictors of community composition were potential evaporation, latitude and maximum relative humidity, while the strongest multifactor model contained elevation, potential evaporation and maximum relative humidity. Temperature, land use variables and distance to natural areas did not significantly correlate with community composition. Non-phytophagous beetles were also captured and were highly diverse (32 families) perhaps representing important beneficial insects.

  14. Snow distribution throughout small subalpine catchment post-insect infestation of spruce and pine beetle.

    NASA Astrophysics Data System (ADS)

    Beverly, D.; Ewers, B. E.; Hyde, K.; Ohara, N.; Speckman, H. N.

    2015-12-01

    High elevation watersheds of the Rocky Mountains region contribute over 70% of the streamflow needed for infrastructure, agriculture, and ecological processes. Snow-water yields are heterogeneous in space and time and are driven by a multitude of snow distribution processes, including snowpack evolution driven by physical and biological factors. Quantifying heterogeneity of snowpack is further complicated by vegetation perturbations; much of the Rocky Mountains have experienced significant tree mortality due to bark beetle outbreaks. Reduction of living crown area decreases canopy interception while increasing radiation to snow surfaces, which alters snowpack distribution throughout the catchment. We hypothesize that, in a complex watershed, topographic variation (i.e., slope and aspect) will have a greater effect on snowpack evolution and distribution than densities of canopy mortality due to beetle infestation. The 120 ha No Name watershed, located in southern Wyoming at 3000 m elevation was divided into twenty-one 175 m2 parcels, in which plots were randomly assigned within each parcel. Peak snow was measured in April; in the 50 m2 plots, depths were measured every 2 m along north-south and east-west transects. Twenty-one snow pits were excavated to quantify snow densities in 10 cm increments throughout the pit profile. Forest inventories occurred the following summer. Peak snowpack levels occurred in April with mean depth of 92.3 ­­± 2.4 cm and peak SWE of 34.0 ± 0.84 cm. Binary decision trees accounted for 63% of the variability after including topographic indices, beetle condition of the trees, LAI, and basal area. Snow depth showed a slight positive relationship with increased in beetle mortality on slopes less than 11 degrees. Overall, topographic indices are greater drivers for snow distributions compared to effects of tree mortality.

  15. Triterpenoid glycosides from bark of Meliosma lanceolata.

    PubMed

    Abe, F; Yamauchi, T; Shibuya, H; Kitagawa, I

    1996-06-01

    From the bark of Meliosma lanceolate, nine triterpenoid glycosides including the 28-O-beta-D-glucopyranosyl ester of bayogenin-3-O-beta-D-glucuronopyranoside, its 4'-O-beta-D-galactopyranoside and 4'-O-alpha-L-arabinopyranoside were isolated and the structures characterized along with that of 28-O-beta-D-glucopyranosyl-bayogenin-3-O-beta-D-4'-anhydro-4', 5'-didehydroglucuronopyranoside. Bisdesmosidic triosides of hederagenin were obtained as minor components.

  16. Phytochemical analysis of Pinus eldarica bark

    PubMed Central

    Iravani, S.; Zolfaghari, B.

    2014-01-01

    Bark extract of Pinus pinaster contains numerous phenolic compounds such as catechins, taxifolin, and phenolic acids. These compounds have received considerable attentions because of their anti-inflammatory, antimutagenic, anticarcinogenic, antimetastatic and high antioxidant activities. Although P. pinaster bark has been intensely investigated in the past; there is comparably less information available in the literature in regard to P. eldarica bark. Therefore, the aim of this study was to determine the chemical composition of P. eldarica commonly found in Iran. A reversed-phase high pressure liquid chromatography (RP-HPLC) method for the determination of catechin, caffeic acid, ferulic acid, and taxifolin in P. pinaster and P. eldarica was developed. A mixture of 0.1% formic acid in deionized water and 0.1% formic acid in acetonitrile was used as the mobile phase, and chromatographic separation was achieved on a Nova pack C18 at 280 nm. The two studied Pinus species contained high amounts of polyphenolic compounds. Among four marker compounds, the main substances identified in P. pinaster and P. eldarica were taxifolin and catechin, respectively. Furthermore, the composition of the bark oil of P. eldarica obtained by hydrodistillation was analyzed by gas chromatography/mass spectroscopy (GC/MS). Thirty-three compounds accounting for 95.1 % of the oil were identified. The oils consisted mainly of mono- and sesquiterpenoid fractions, especially α-pinene (24.6%), caryophyllene oxide (14.0%), δ-3-carene (10.7%), (E)-β-caryophyllene (7.9%), and myrtenal (3.1%). PMID:25657795

  17. Lunar orientation in a beetle.

    PubMed

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

    2004-02-22

    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.

  18. The 'WHY?' files: the case of the barking dog

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In this program, students are invited to actively join the tree house detectives as they investigate the 'Case of the Barking Dogs.' The tree house detectives accept the challenge of determining why dogs in the surrounding neighborhoods have unexpectedly started barking early in the morning and late at night. Using scientific inquiry, our detectives discover what is causing the neighborhood dogs to bark. In determining the 'why,' the detectives learn about sound: what it is, how it is transmitted, how people and animals hear, and NASA's research on noise. While solving the case, the tree house detectives learn that determining the source of the barking requires the use of logic and 'sound' reasoning.

  19. Unusual coloration in scarabaeid beetles

    NASA Astrophysics Data System (ADS)

    Brink, D. J.; van der Berg, N. G.; Prinsloo, L. C.; Hodgkinson, I. J.

    2007-04-01

    In this paper we investigate the reflection of circularly polarized light from the exocuticle of the scarabaeid beetle Gymnopleurus virens. Reflection spectra are deeply modulated, exhibiting a number of relatively narrow well-defined peaks, which differ from previously studied specimens. By comparing model calculations and electron microscopy work with the recorded spectra, we can propose the presence of specific structural defects responsible for the unusual spectra.

  20. Newly Discovered Transmission Pathway of Bursaphelenchus xylophilus from Males of the Beetle Monochamus alternatus to Pinus densiflora Trees via Oviposition Wounds.

    PubMed

    Arakawa, Yoh; Togashi, Katsumi

    2002-12-01

    The transmission of Bursaphelenchus xylophilus from Monochamus alternatus males to Pinus densiflora trees via oviposition wounds has been determined. Nematode-infested males, with mandibles fixed experimentally to prevent feeding, were placed for 48 hours with pine bolts containing oviposition wounds that had been made by nematode-free females. After removal of the nematode-infested males, the pine bolts were held for 1 month and then examined for the presence of nematodes. Reproducing nematode populations were recovered from pine bolts that were exposed to male beetles carrying a high number of nematodes. No reproducing nematode population could be recovered from pine bolts exposed to beetles with a small number of nematodes. Nematode reproduction in the pine bolts was not related to the number of oviposition wounds per bolt. Fourth-stage dispersal B. xylophilus juveniles, collected from beetle body surfaces, were inoculated on pine bolt bark 0, 5, 10, and 15 cm away from a single artificial, small hole. These dauer juveniles successfully entered some bolts. The probability of successful nematode reproduction decreased with increased distance between inoculation point and artificial hole. The results indicated that B. xylophilus can move a significant distance to oviposition wounds along the bark surface and enter a tree via the wounds. The new transmission pathway is considered important for the nematode to persist in pine forests such as in North America where pine wilt disease does not occur.

  1. Mountain pine beetle disturbance effects on soil respiration and nutrient pools

    NASA Astrophysics Data System (ADS)

    Trahan, N. A.; Moore, D. J.; Brayden, B. H.; Dynes, E.; Monson, R. K.

    2011-12-01

    Over the past decade, the mountain pine beetle Dendroctonos ponderosae has infested more than 86 million hectares of high elevation forest in the Western U.S.A. While bark beetles are endemic to western forests and important agents of regeneration, the current mountain pine beetle outbreak is larger than any other on record and the resulting tree mortality has significant consequences for nutrient cycling and regional carbon exchange. We established decade-long parallel disturbance chronosequences in two lodgepole pine (Pinus contorta) forests in Colorado: one composed of mountain pine beetle killed lodgepole stands and one consisting of trees where beetle mortality was simulated by stem girdling. Over the 2010 and 2011 growing season we measured plot level soil respiration fluxes, as well as soil extractable dissolved organic carbon, nitrogen, microbial biomass carbon and nitrogen, and pools of ammonium, nitrate and inorganic phosphorus. We show that soil respiration sharply declines with gross primary productivity after tree mortality, but rebounds during the next 4 years, then declines again from 6-8 years post-disturbance. Soil extractable dissolved organic carbon, microbial biomass carbon, and inorganic phosphorous pools follow the pattern observed in soil respiration fluxes across disturbance age classes for both sites, while patterns in total dissolved nitrogen exhibit site specific variation. Levels of detectable soil nitrate were low and did not significantly change across the chronosequence, while soil ammonium increased in a similar pattern with soil moisture in disturbed plots. These patterns in soil respiration and nutrient pools reflect the loss of autotrophic respiration and rhizodeposition immediately after tree mortality, followed by a pulse in soil efflux linked to the decomposition of older, less labile carbon pools. This pulse is likely controlled by the fall rate of litter, coarse woody debris and the relative impact of post-disturbance water

  2. Applying a gaming approach to IP strategy.

    PubMed

    Gasnier, Arnaud; Vandamme, Luc

    2010-02-01

    Adopting an appropriate IP strategy is an important but complex area, particularly in the pharmaceutical and biotechnology sectors, in which aspects such as regulatory submissions, high competitive activity, and public health and safety information requirements limit the amount of information that can be protected effectively through secrecy. As a result, and considering the existing time limits for patent protection, decisions on how to approach IP in these sectors must be made with knowledge of the options and consequences of IP positioning. Because of the specialized nature of IP, it is necessary to impart knowledge regarding the options and impact of IP to decision-makers, whether at the level of inventors, marketers or strategic business managers. This feature review provides some insight on IP strategy, with a focus on the use of a new 'gaming' approach for transferring the skills and understanding needed to make informed IP-related decisions; the game Patentopolis is discussed as an example of such an approach. Patentopolis involves interactive activities with IP-related business decisions, including the exploitation and enforcement of IP rights, and can be used to gain knowledge on the impact of adopting different IP strategies.

  3. Vaccines and IP Rights: A Multifaceted Relationship.

    PubMed

    Durell, Karen

    2016-01-01

    Just as there are many forms of vaccines and components to vaccines-particular compositions, delivery systems, components, and distribution networks-there are a variety of intellectual property (IP) protections applicable for vaccines. IP rights such as patent, copyright, trademarks, plant breeders' rights, and trade secrets may all be applicable to vaccines. Thus, discussion of IP rights and vaccines should not begin and end with the application of one IP right to a vaccine. The discussion should engage considerations of multiple IP rights applicable to a vaccine and how these can be utilized in an integrated manner in a strategy aimed at supporting the development and distribution of the vaccine. Such an approach to IP rights to vaccines allows for the integrated rights to be considered in light of the justifications for protecting vaccines with IP rights, as well as the issues relating to specific IP rights for vaccines, such as compulsory license regimes, available humanitarian purpose IP credits, etc. To view vaccines as the subject of multiple IP protections involves a refocusing, but the outcome can provide significant benefits for vaccine development and distribution.

  4. Acoustic characteristics of rhinoceros beetle stridulations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stridulation behavior has been reported for adults and larvae of many dynastids. This report describes acoustic recordings and analyses of stridulations by larvae of two Southeastern Asia rhinoceros beetle species and by adults of the coconut rhinoceros beetle. The behavioral context of the strid...

  5. Ground beetle (Coleoptera: Carabidae) feeding ecology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This article reviews some general and applied aspects of the feeding ecology of carabid beetles. General aspects included feeding preferences, prey searching, prey capture, and digestion. Applied aspects included evidence of impact, such as predation of aphids, leafhoppers, flies, beetles and moth...

  6. Ground beetle (Coleoptera: Carabidae) feeding ecology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The article reviews some general and applied aspects of the feeding ecology of carabid beetles. General aspects included feeding preferences, prey searching, prey capture, and digestion. Applied aspects included evidence of impact, such as predation of aphids, leafhoppers, flies, beetles and moths...

  7. 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...

  8. 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...

  9. 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...

  10. Analysis of Handoff Mechanisms in Mobile IP

    NASA Astrophysics Data System (ADS)

    Jayaraj, Maria Nadine Simonel; Issac, Biju; Haldar, Manas Kumar

    2011-06-01

    One of the most important challenges in mobile Internet Protocol (IP) is to provide service for a mobile node to maintain its connectivity to network when it moves from one domain to another. IP is responsible for routing packets across network. The first major version of IP is the Internet Protocol version 4 (IPv4). It is one of the dominant protocols relevant to wireless network. Later a newer version of IP called the IPv6 was proposed. Mobile IPv6 is mainly introduced for the purpose of mobility. Mobility management enables network to locate roaming nodes in order to deliver packets and maintain connections with them when moving into new domains. Handoff occurs when a mobile node moves from one network to another. It is a key factor of mobility because a mobile node can trigger several handoffs during a session. This paper briefly explains on mobile IP and its handoff issues, along with the drawbacks of mobile IP.

  11. [iPS cells in dentistry].

    PubMed

    Egusa, Hiroshi

    2012-01-01

    The discovery of the induced pluripotent stem (iPS) cell technology, which enables us to produce pluripotent stem cells by introducing a few genetic factors, commands considerable attention in the field of dentistry. These iPS cells may be of particular importance for developing innovative technologies to regenerate missing jaw bones and lost teeth, and there are expectations that several types of tissue stem cells and mucosal cells in the oral area can be used as an ideal iPS cell source. We previously reported that the gingiva, which is often resected during general dental treatments and treated as biomedical waste, is a promising source of iPS cells. In this review, the current trends in iPS cell research in dentistry are outlined, and future aspects of potential applications of the iPS cell technologies to dental treatments will be discussed.

  12. 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

  13. 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.

  14. Antinociceptive effect of aqueous extracts from the bark of Croton guatemalensis Lotsy in mice.

    PubMed

    Del Carmen, Rejón-Orantes José; Willam, Hernández Macías John; Del Carmen, Grajales Morales Azucena; Nataly, Jiménez-García; Stefany, Coutiño Ochoa Samantha; Anahi, Cañas Avalos; Domingo, Parcero Torres Jorge; Leonardo, Gordillo Páez; Miguel, Pérez de la Mora

    2016-01-01

    Croton guatemalensis Lotsy (CGL), known as "copalchi" in Chiapas, Mexico, is used for the treatment of fever, abdominal pain and malaria and also as a remedy for chills and for treating rheumatism. The aim of this study was to evaluate whether aqueous extracts from the bark of this plant possesses indeed antinociceptive properties by using two different animal models of nociception, the acetic acid-induced writhing test and the hot plate model. The results showed that i.p. administration of this extract (0, 100, 200 and 400 mg/kg) 30 min prior testing had significant dose-dependent antinociceptive effects in the acetic acid-induced writhing test and that the reduction of writhings (85.5 % as compared to the control) at the highest dose tested is similar to that exhibited by dipyrone (250 mg/kg). This effect was not reversed by naloxone, a non-selective opioid receptor antagonist, suggesting that the endogenous opioid system does not underlie the antinociceptive effects of CGL in the acetic acid-induced writhing test. No effects were however observed in the hot-plate model. Our results indicate that aqueous extracts from Croton guatemalensis bark contain pharmacologically active constituents endowed with antinociceptive activity. It is suggested that cyclooxygenase inhibition might be at least partially involved in the antinociceptive effects of this extract.

  15. Antinociceptive effect of aqueous extracts from the bark of Croton guatemalensis Lotsy in mice

    PubMed Central

    del Carmen, Rejón-Orantes José; Willam, Hernández Macías John; del Carmen, Grajales Morales Azucena; Nataly, Jiménez-García; Stefany, Coutiño Ochoa Samantha; Anahi, Cañas Avalos; Domingo, Parcero Torres Jorge; Leonardo, Gordillo Páez; Miguel, Pérez de la Mora

    2016-01-01

    Croton guatemalensis Lotsy (CGL), known as “copalchi” in Chiapas, Mexico, is used for the treatment of fever, abdominal pain and malaria and also as a remedy for chills and for treating rheumatism. The aim of this study was to evaluate whether aqueous extracts from the bark of this plant possesses indeed antinociceptive properties by using two different animal models of nociception, the acetic acid-induced writhing test and the hot plate model. The results showed that i.p. administration of this extract (0, 100, 200 and 400 mg/kg) 30 min prior testing had significant dose-dependent antinociceptive effects in the acetic acid-induced writhing test and that the reduction of writhings (85.5 % as compared to the control) at the highest dose tested is similar to that exhibited by dipyrone (250 mg/kg). This effect was not reversed by naloxone, a non-selective opioid receptor antagonist, suggesting that the endogenous opioid system does not underlie the antinociceptive effects of CGL in the acetic acid-induced writhing test. No effects were however observed in the hot-plate model. Our results indicate that aqueous extracts from Croton guatemalensis bark contain pharmacologically active constituents endowed with antinociceptive activity. It is suggested that cyclooxygenase inhibition might be at least partially involved in the antinociceptive effects of this extract. PMID:27051428

  16. Toxicological and phytochemical studies of Aspidosperma subincanum Mart. stem bark (Guatambu).

    PubMed

    Santos, S R; Rangel, E T; Lima, J C S; Silva, R M; Lopes, L; Noldin, V F; Cechinel Filho, V; Delle Monache, F; Martins, D T O

    2009-12-01

    Aspidosperma subincanum Mart. is widely used in Brazilian folk medicine to treat digestive disorders. In this study, acute and subchronic toxicity and cytotoxicity of stem bark ethanolic extract of Aspidosperma subincanum (EEAs) have been evaluated. In addition, phytochemical analysis was performed. The EEAs had low acute toxicity in mice with LD50 =1129 +/- 154mg/kg p.o. and 397 +/- 15 mg/kg i.p. The LC50 was 1340 +/- 428 microg/mL in the brine shrimp assay. There was no relevance of serious changes in behavioral, hematological and biochemical parameters and no deleterious effect on vital organs of rats that resulted after 30 days daily exposure to 5 and 100 mg/kg of EEAs. Phytochemical analysis of stem bark of A. subincanum revealed the presence of indole alkaloids, saponins, terpenoids, steroids and tannins and resulted in the isolation of oleic acid and guatambuine as major constituents. Using the method of the dose by factor approach, the human safe dose was 210 mg/70 kg/day. The EEAs appears to be safe and non-toxic in low doses in rodents and domestic preparations used by population have relatively security.

  17. Preventive effects of Eleutherococcus senticosus bark extract in OVX-induced osteoporosis in rats.

    PubMed

    Lim, Dong Wook; Kim, Jae Goo; Lee, Youngseok; Cha, Seok Ho; Kim, Yun Tai

    2013-07-08

    Eleutherococcus senticosus (Siberian ginseng), has been used as a powerful tonic herb with an impressive range of health benefits. This medicinal herb has been commonly used to treat bone metabolism diseases due to its traditional Korean medicine use to strengthen muscle and bone. This study was conducted to investigate prevention of bone loss by a standardized extract of dried E. senticosus stem bark in an ovariectomized (OVX) rat model of osteoporosis. The OVX groups were divided into five groups treated with distilled water, 17β-estradiol (E2 10 μg/kg, once daily, i.p) and dried stem bark of E. senticosus extracts (DES 10, 30, and 100 mg/kg, once daily, p.o) for eight weeks, respectively. After eight weeks of treatments, the femur bone mineral density of the 100 mg/kg DES-treated group was significantly higher than that of the OVX-control group (16.7%, p < 0.01) without affecting the body, organs, and uterus weights, and serum estradiol levels. Additionally, bone markers such as serum ALP, CTx, and OC levels were significantly decreased in the DES 100 mg/kg treated group. These results show that DES is able to prevent OVX-induced in bone loss without the influence of hormones such as estrogen.

  18. Structure of mouse IP-10, a chemokine

    SciTech Connect

    Jabeen, Talat; Leonard, Philip; Jamaluddin, Haryati; Acharya, K. Ravi

    2008-06-01

    The structure of mouse IP-10 shows a novel tetrameric association. Interferon-γ-inducible protein (IP-10) belongs to the CXC class of chemokines and plays a significant role in the pathophysiology of various immune and inflammatory responses. It is also a potent angiostatic factor with antifibrotic properties. The biological activities of IP-10 are exerted by interactions with the G-protein-coupled receptor CXCR3 expressed on Th1 lymphocytes. IP-10 thus forms an attractive target for structure-based rational drug design of anti-inflammatory molecules. The crystal structure of mouse IP-10 has been determined and reveals a novel tetrameric association. In the tetramer, two conventional CXC chemokine dimers are associated through their N-terminal regions to form a 12-stranded elongated β-sheet of ∼90 Å in length. This association differs significantly from the previously studied tetramers of human IP-10, platelet factor 4 and neutrophil-activating peptide-2. In addition, heparin- and receptor-binding residues were mapped on the surface of IP-10 tetramer. Two heparin-binding sites were observed on the surface and were present at the interface of each of the two β-sheet dimers. The structure supports the formation of higher order oligomers of IP-10, as observed in recent in vivo studies with mouse IP-10, which will have functional relevance.

  19. alpha-Glucosidase inhibitory activity of Mangifera indica bark.

    PubMed

    Prashanth, D; Amit, A; Samiulla, D S; Asha, M K; Padmaja, R

    2001-08-01

    The ethanolic extracts of Lawsonia inermis leaves, Holarrhena antidysenterica bark, Swertia chirata whole plant and Mangifera indica bark were tested (in-vitro) for alpha-glucosidase inhibitory activity. M. indica extract was found to be the most potent, with an IC(50) value of 314 microg/ml.

  20. A Solution for Irregular IP Multicast Packet Flooding — For Heavy Traffic IP Multicast Communication

    NASA Astrophysics Data System (ADS)

    Misumi, Makoto; Nakagawa, Shin-Ichi; Chinen, Ken-Ichi; Shinoda, Yoichi; Yamaoka, Katsunori

    When an IP Multicast network is constructed on a switch-based network, many IP Multicast packet broadcasts are generated, and these broadcasts cause trouble for all of the other kinds of communication. To solve this problem, implementing IGMP Snooping on various switches has been proposed. However, some switches have insufficient IP Multicast packet-handling capability. This problem is also mentioned in RFC4541. In this paper, we propose the IGMP Snooping Activator (ISA) mechanism as a way to solve the IP Multicast packet-handling problem. The ISA transmits dummy IGMP Queries to maintain the IP Multicast network, and it joins the flooding IP Multicast group to activate IGMP Snooping in switches that are unable to handle IP Multicast packets. The experimental evaluation shows the effectiveness of our proposed method: the network load decreases because of the method's effective restraint of IP Multicast packet flooding.

  1. Polychlorinated biphenyl accumulation in tree bark and wood growth rings

    SciTech Connect

    Meredith, M.L.; Hites, R.A.

    1987-07-01

    Polychlorinated biphenyls (PCBs) were found in the bark of black walnut and tulip poplar trees growing near a PCB-contaminated landfill. PCBs were also found in the bark of white oak trees growing 14 km away from the landfill. The concentration of individual congeners in the bark averaged 18 ppb at the landfill and 0.5 ppb at the other site. The PCB congeners were accumulated into the bark in proportion to their lipophilicity (as measured by octanol-water partition coefficients). The authors findings suggest that tree bark could be used for biomonitoring of lipophilic organic pollutants in the atmosphere. There is little evidence that PCBs are present in the wood of trees. The signal to blank ratios are always less than 3, and the relative concentrations between 20-year time intervals do not show trends that correlate with the known inputs of PCBs in Bloomington, IN. 2 tables.

  2. Approaches for Resolving Dynamic IP Addressing.

    ERIC Educational Resources Information Center

    Foo, Schubert; Hui, Siu Cheung; Yip, See Wai; He, Yulan

    1997-01-01

    A problem with dynamic Internet protocol (IP) addressing arises when the Internet connection is through an Internet provider since the IP address is allocated only at connection time. This article examines a number of online and offline methods for resolving the problem. Suggests dynamic domain name system (DNS) and directory service look-up are…

  3. VoIP to the Rescue

    ERIC Educational Resources Information Center

    Milner, Jacob

    2005-01-01

    Voice over Internet Protocol (VoIP) is everywhere. The technology lets users make and receive phone calls over the Internet, transporting voice traffic alongside data traffic such as instant messages (IMs) and e-mail. While the number of consumer customers using VoIP increases every week, the technology is finding its way into K-12 education as…

  4. Evaluating a humane alternative to the bark collar: Automated differential reinforcement of not barking in a home-alone setting.

    PubMed

    Protopopova, Alexandra; Kisten, Dmitri; Wynne, Clive

    2016-12-01

    The aim of this study was to develop a humane alternative to the traditional remote devices that deliver punishers contingent on home-alone dog barking. Specifically, we evaluated the use of remote delivery of food contingent on intervals of not barking during the pet owner's absence. In Experiment 1, 5 dogs with a history of home-alone nuisance barking were recruited. Using an ABAB reversal design, we demonstrated that contingent remote delivery of food decreased home-alone barking for 3 of the dogs. In Experiment 2, we demonstrated that it is possible to thin the differential-reinforcement-of-other-behavior (DRO) schedule gradually, resulting in a potentially more acceptable treatment. Our results benefit the dog training community by providing a humane tool to combat nuisance barking.

  5. SN2009ip at Very Late Times

    NASA Astrophysics Data System (ADS)

    Bigley, Andrew Christopher; Graham, Melissa Lynn

    2016-01-01

    The 2012 eruption of SN 2009ip resembled a Type IIn supernovae, dominated by emission from interaction of the ejecta with circumstellar material, but the question remains: was the 2012 outburst of SN 2009ip truly the terminal explosion of a massive star? We present time series photometric and spectroscopic data for the transient SN2009ip from 260 to 1026 days after the peak of its 2012 outburst. These data were collected at the Las Cumbres Observatory Global Telescope Network and Keck Observatory. We will show that SN 2009ip continues to decline linearly in brightness at very late epochs, analyze the evolution in flux and asymmetry of the Balmer emission lines, and investigate the geometry of the circumstellar material from the progenitor star system and the true nature of SN 2009ip.

  6. Analysis of all-optical IP routers

    NASA Astrophysics Data System (ADS)

    Tamil, Lakshman S.; Masetti, Francesco B.; McDermott, Thomas C.; Castanon, Gerardo; Ge, Andrew; Tancevski, Ljubisa

    1998-10-01

    The increased data traffic experienced today and the projected increase in the data traffic in the future demand exploration of novel approaches to IP transport such as transport of IP traffic over optics. The bimodal nature of the IP traffic short packets which are typical of transactional-style flows and large packets or bursts which are encountered in the transport of large data blocks requires, design of routers that are capable of routing packets with variable lengths efficiently. In this paper, we discuss the design aspects of such all-optical IP-switches. The broadcast and select architecture is a prime candidate for implementing optical IP routers. Construction of optical routers with buffering, wavelength conversion and multipath routing are considered. The merits and demerits of all these cases and the effect of buffer size, wavelength conversion and multiple-path routing on the blocking probability and probability of packet loss are discussed.

  7. 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

  8. Space Network IP Services (SNIS): An Architecture for Supporting Low Earth Orbiting IP Satellite Missions

    NASA Technical Reports Server (NTRS)

    Israel, David J.

    2005-01-01

    The NASA Space Network (SN) supports a variety of missions using the Tracking and Data Relay Satellite System (TDRSS), which includes ground stations in White Sands, New Mexico and Guam. A Space Network IP Services (SNIS) architecture is being developed to support future users with requirements for end-to-end Internet Protocol (IP) communications. This architecture will support all IP protocols, including Mobile IP, over TDRSS Single Access, Multiple Access, and Demand Access Radio Frequency (RF) links. This paper will describe this architecture and how it can enable Low Earth Orbiting IP satellite missions.

  9. Semiochemical-mediated flight responses of sap beetle vectors of oak wilt, Ceratocystis fagacearum.

    PubMed

    Kyhl, John F; Bartelt, Robert J; Cossé, Allard; Juzwik, Jennifer; Seybold, Steven J

    2002-08-01

    The sap beetle, Colopterus truncatus (Coleoptera: Nitidulidae), is one of the primary vectors of the oak wilt pathogen, Ceratocystis fagacearum, in the north-central United States. Field behavioral assays utilizing various release rates and blends of three methyl-branched hydrocarbon aggregation pheromone components showed that flight responses of this beetle were similar in Illinois and Minnesota populations. In both locations, both sexes of the beetle responded synergistically to a combination of the three-component pheromone and fermenting whole-wheat bread dough. Further, Colopterus truncatus preferred a high release rate over a low release rate of the three-component blend. In both locations, the response of C. truncatus to a simplified version of the pheromone consisting of (2E,4E,6E)-3,5-dimethyl-2,4,6-octatriene (1) and (2E,4E,6E,8E)-3,5,7-trimethyl-2,4,6,8-decatetraene (3) was not significantly different from the response to the three-component blend. An experiment in Illinois with all possible combinations of the components demonstrated that the decatetraene (3) was the crucial component in the blend; of all treatments, the maximal response was elicited by 3 + dough. Chipped bark, phloem, and xylem from northern pin oak, Quercus ellipsoidalis, was not attractive to C. truncatus in Minnesota. During a weekly survey over two seasons in Minnesota, C. truncatus flew in response to the three-component pheromone between early April and early July, with the maximum responses coming on May 4, 2000 and April 20, 2001. During both years, more than 98% of the beetles were trapped between April 14 and June 1. During the same survey, Glischrochilus spp. (Nitiduildae) flew during longer periods of the summer, particularly in 2001. The sex ratio of C. truncatus responding during all experiments was female-biased (1.8:1, female-male), which is characteristic of other male-produced coleopteran aggregation pheromones. Other sap beetles that play a minor role in the

  10. Aboveground Tree Carbon Stocks and Flux Following Mountain Pine Beetle Outbreaks

    NASA Astrophysics Data System (ADS)

    Pfeifer, E. M.; Hicke, J. A.

    2008-12-01

    Mountain pine beetle outbreaks result in tree mortality across millions of acres in North America, with significant effects on forest ecosystem processes such as carbon cycling. Following outbreak-related mortality, forest stands continue taking up carbon (C) via the growth of 1) surviving trees and/or 2) tree seedlings that establish during and after outbreaks. To date, the degree to which surviving trees can, in the absence of post-outbreak seedling establishment, recover pre-outbreak C stocks and flux is largely unknown. To address this uncertainty we asked: (1) Do aboveground stocks and flux among pure lodgepole pine stands recover to pre-outbreak levels independent of post-outbreak regeneration? 2) What is the long-term effect of the mountain pine beetle outbreaks on modeled aboveground C stocks and flux? We used measurements from several stands affected by a recent mountain pine beetle outbreak as input to the Forest Vegetation Simulator, an individual tree-based growth model, to predict stand-level aboveground C stocks and flux. The simulation time period spanned from just prior to the bark beetle outbreak and for 200 years following outbreak collapse. At five-year intervals, we compared C stocks and fluxes in stands affected by the disturbance to conditions in the same stands immediately preceding the outbreak, as well as identical stands modeled as if the outbreak had not occurred. Crown closure of surviving trees was predicted by the model in all stands following outbreak collapse, but measured outbreak mortality did not significantly reverse increases of growth dominance by relatively large trees. Stand-level growth dominance and increases of stand density following crown closure have been associated with declines in stand-level primary productivity and productivity efficiency. Thus, unlike stand- level C stocks, predicted C flux did not recover relative to pre-outbreak levels, although we observed basic patterns of C flux rise, peak, and long

  11. Outbreeding depression, but no inbreeding depression in haplodiploid Ambrosia beetles with regular sibling mating.

    PubMed

    Peer, Katharina; Taborsky, Michael

    2005-02-01

    In sexual reproduction the genetic similarity or dissimilarity between mates strongly affects offspring fitness. When mating partners are too closely related, increased homozygosity generally causes inbreeding depression, whereas crossing between too distantly related individuals may disrupt local adaptations or coadaptations within the genome and result in outbreeding depression. The optimal degree of inbreeding or outbreeding depends on population structure. A long history of inbreeding is expected to reduce inbreeding depression due to purging of deleterious alleles, and to promote outbreeding depression because of increased genetic variation between lineages. Ambrosia beetles (Xyleborini) are bark beetles with haplodiploid sex determination, strong local mate competition due to regular sibling mating within the natal chamber, and heavily biased sex ratios. We experimentally mated females of Xylosandrus germanus to brothers and unrelated males and measured offspring fitness. Inbred matings did not produce offspring with reduced fitness in any of the examined life-history traits. In contrast, outcrossed offspring suffered from reduced hatching rates. Reduction in inbreeding depression is usually attributed to purging of deleterious alleles, and the absence of inbreeding depression in X. germanus may represent the highest degree of purging of all examined species so far. Outbreeding depression within the same population has previously only been reported from plants. The causes and consequences of our findings are discussed with respect to mating strategies, sex ratios, and speciation in this unusual system.

  12. Bioactive Fraction of Annona reticulata Bark (or) Ziziphus jujuba Root Bark along with Insulin Attenuates Painful Diabetic Neuropathy through Inhibiting NF-κB Inflammatory Cascade

    PubMed Central

    Kandimalla, Raghuram; Dash, Suvakanta; Kalita, Sanjeeb; Choudhury, Bhaswati; Malampati, Sandeep; Devi, Rajlakshmi; Ramanathan, Muthiah; Talukdar, Narayan C.; Kotoky, Jibon

    2017-01-01

    The present study explains the neuroprotective ability of bioactive fractions of Annona reticulata bark (ARB) and Ziziphus jujuba root bark (ZJ) along with insulin against diabetic neuropathy. By using different solvents of increasing polarity ARB and ZJ were undergone for bioactive guided fractionation. The neuroprotective ability of the all the plant fractions were tested against H2O2 induced toxicity in SHSY5Y neuroblastoma cell lines and DRG neuronal cells. Among all the fractions tested, the methanol extract of ARB and ZJ (ARBME and ZJME) and its water fractions (ARBWF and ZJWF) exhibited significant neuroprotection against H2O2 induced toxicity in SHSY5Y cells and DRG neuronal cells. Further both the active fractions were tested against streptozotocin (55 mg/kg i.p.) induced diabetic neuropathy in male Wistar rats. Body weight changes, blood glucose levels and pain threshold through hot plate, tail immersion, cold plate and Randall-Sillitto methods were measured throughout the study at weekly interval. After completion of the drug treatment period, all the animals were sacrificed to measure the sciatic nerve lipid peroxidation, antioxidative enzyme levels (SOD, catalase, and GSH) and cytokine levels (IL-1β, IL-6, IL-10, TNF-α, iNOS, and NFκB) through ELISA and western blotting analysis. Results of this study explain that ARBME, ZJME, ARBWF, and ZJWF along with insulin potentially attenuate the thermal, mechanical hyperalgesia and cold allodynia in diabetic neuropathic rats, where insulin treatment alone failed to diminish the same. Reduction of sciatic nerve oxidative stress, NF-κB and iNOS mediated inflammatory cascade and normalization of abnormal cytokine release confirms the possible mechanism of action. The present study confirms the neuroprotective ability of ARB and ZJ against painful diabetic neuropathy through inhibiting oxidative stress and NF-κB inflammatory cascade. PMID:28381989

  13. Bioactive Fraction of Annona reticulata Bark (or) Ziziphus jujuba Root Bark along with Insulin Attenuates Painful Diabetic Neuropathy through Inhibiting NF-κB Inflammatory Cascade.

    PubMed

    Kandimalla, Raghuram; Dash, Suvakanta; Kalita, Sanjeeb; Choudhury, Bhaswati; Malampati, Sandeep; Devi, Rajlakshmi; Ramanathan, Muthiah; Talukdar, Narayan C; Kotoky, Jibon

    2017-01-01

    The present study explains the neuroprotective ability of bioactive fractions of Annona reticulata bark (ARB) and Ziziphus jujuba root bark (ZJ) along with insulin against diabetic neuropathy. By using different solvents of increasing polarity ARB and ZJ were undergone for bioactive guided fractionation. The neuroprotective ability of the all the plant fractions were tested against H2O2 induced toxicity in SHSY5Y neuroblastoma cell lines and DRG neuronal cells. Among all the fractions tested, the methanol extract of ARB and ZJ (ARBME and ZJME) and its water fractions (ARBWF and ZJWF) exhibited significant neuroprotection against H2O2 induced toxicity in SHSY5Y cells and DRG neuronal cells. Further both the active fractions were tested against streptozotocin (55 mg/kg i.p.) induced diabetic neuropathy in male Wistar rats. Body weight changes, blood glucose levels and pain threshold through hot plate, tail immersion, cold plate and Randall-Sillitto methods were measured throughout the study at weekly interval. After completion of the drug treatment period, all the animals were sacrificed to measure the sciatic nerve lipid peroxidation, antioxidative enzyme levels (SOD, catalase, and GSH) and cytokine levels (IL-1β, IL-6, IL-10, TNF-α, iNOS, and NFκB) through ELISA and western blotting analysis. Results of this study explain that ARBME, ZJME, ARBWF, and ZJWF along with insulin potentially attenuate the thermal, mechanical hyperalgesia and cold allodynia in diabetic neuropathic rats, where insulin treatment alone failed to diminish the same. Reduction of sciatic nerve oxidative stress, NF-κB and iNOS mediated inflammatory cascade and normalization of abnormal cytokine release confirms the possible mechanism of action. The present study confirms the neuroprotective ability of ARB and ZJ against painful diabetic neuropathy through inhibiting oxidative stress and NF-κB inflammatory cascade.

  14. Scalable IP switching based on optical interconnect

    NASA Astrophysics Data System (ADS)

    Luo, Zhixiang; Cao, Mingcui; Liu, Erwu

    2000-10-01

    IP traffic on the Internet and enterprise networks has been growing exponentially in the last several years, and much attention is being focused on the use of IP multicast for real-time multimedia applications. The current soft and general-purpose CPU-based routers face great stress since they have great latency and low forwarding speeds. Based on the ASICs, layer 2 switching provides high-speed packet forwarding. Integrating high-speed of Layer 2 switching with the flexibility of Layer 3 routing, Layer 3 switching (IP switching) has been put forward in order to avoid the performance bottleneck associated with Layer 3 forwarding. In this paper, we present a prototype system of a scalable IP switching based on scalable ATM switching fabric and optical interconnect. The IP switching system mainly consists of the input/output interface unit, scalable ATM switching fabric and IP control component. Optical interconnects between the input fan-out stage and the interconnect stage, also the interconnect stage and the output concentration stage provide high-speed data paths. And the interconnect stage is composed of 16 X 16 CMOS-SEED ATM switching modules. With 64 ports of OC-12 interface, the maximum throughput of the prototype system is about 20 million packets per second (MPPS) for 256 bytes average packet length, and the packet loss ratio is less than 10e-9. Benefiting from the scalable architecture and the optical interconnect, this IP switching system can easily scale to very large network size.

  15. A model for peak and width of signaling windows: Ips duplicatus and Chilo partellus pheromone component proportions--does response have a wider window than production?

    PubMed

    Schlyter, F; Svensson, M; Zhang, Q H; Knízek, M; Krokene, P; Ivarsson, P; Birgersson, G

    2001-07-01

    (mu = 0.13) but a narrower width, 2sigma = 0.14. Literature data from other moth species showed similar patterns, with a wider male response relative to the female production windows. Literature data on response to enantiomer ratios in a hymenopteran and to pheromone amounts in a dipteran were also described by our model. In a bark beetle population (Ips pini), with two hybridizing enantiomeric strains, the production peaks were narrower (0.1) than the response peaks (0.5). Thus, it in general, seems that in the pheromone systems analyzed, the width of the response window (2sigma = 0.1 to 0.8) is larger than that of the production window (2sigma = 0.03 to 0.14), irrespective of the sex of the sender.

  16. Modeling net ecosystem exchange of carbon dioxide in a beetle-attacked subalpine forest using a data-constrained ecosystem model

    NASA Astrophysics Data System (ADS)

    Peckham, S. D.; Ewers, B. E.; Mackay, D. S.; Frank, J. M.; Massman, W. J.; Ryan, M. G.; Scott, H.; Pendall, E.

    2012-12-01

    The mountain pine and spruce bark beetles and associated blue-stain fungi have caused widespread mortality in the forests of the western U.S. during the past decade, impacting over 1.6 Mha in Northern Colorado and Southeast Wyoming alone. Both the beetles and fungi they carry block tree xylem and eventually cause mortality due to hydraulic failure. Previous studies of bark beetle mortality in Canadian forests have suggested a net loss of carbon following beetle attack. This study aimed to determine if forests in the southern Rocky Mountains showed a similar response. We simulated carbon fluxes over a time period of six years (2005-2010) at the Glacier Lakes Ecosystem Experiment sites (GLEES) Ameriflux site using the Terrestrial Regional Ecosystem Exchange Simulator (TREES) model. This time period included a beetle infestation during the last three years that resulted in mortality of 51% of the spruce trees that accounted for 90% of the spruce basal area. Model estimates of net ecosystem exchange of CO2 (NEE) were compared to eddy-covariance measurements before, during, and after beetle attack. Model predictions of NEE were generated two ways, 1) using the standard set of maintenance respiration coefficients, and 2) constraining modeled respiration using equations derived from field measurements of stem, leaf, and soil respiration at GLEES, and were compared to NEE observations before, during, and after the presence of bark beetles. Model changes included both simple modification of the exponential temperature response curve (Q10) and adding new equations based on both temperature and live tissue nitrogen content. Pre-beetle observed growing season mean NEE averaged -1.49 μmol C m-2 s-1 and simulation means ranged from -4.10 to 0.64 μmol C m-2 s-1. Changing the model's computation of maintenance respiration to incorporate site-specific temperature response (Q10) resulted in an over-prediction of nighttime NEE by up to 100%, but a 10-30% improvement during the day

  17. Bioconversion of eucalyptus bark waste into soil conditioner.

    PubMed

    Yadav, K R; Sharma, R K; Kothari, R M

    2002-01-01

    An optimized protocol for the bioconversion of eucalyptus bark was devised. It comprised: (i) mechanical reduction in bark size to 0.5-3.0 cm, (ii) moistening to 60-65%, (iii) fortification with ligninase-rich fungus Volvariella sp. (S-1) and 2% urea and (iv) maintenance of this composting mix under aerobic and ambient condition for 14-15 weeks. The resulting bark soil conditioner (BSC) was an easily crumbling, reddish brown biomass, with physico-chemical and microbial properties which would enrich soil fertility/productivity.

  18. Polarisation vision: beetles see circularly polarised light.

    PubMed

    Warrant, Eric J

    2010-07-27

    It has long been known that the iridescent cuticle of many scarab beetles reflects circularly polarised light. It now turns out that scarabs can also see this light, potentially using it as a covert visual signal.

  19. Uniform communications software using TCP/IP

    SciTech Connect

    Bernett, M.; Oleynik, G.

    1989-05-01

    Data acquisition applications at Fermilab require a reliable, distributed communication system for downloading, diagnostics, control, and data distribution. TCP/IP over Ethernet was chosen because of its uniform user interface and commercial availability for a number of processors and operating systems. This paper describes our software and hardware support for TCP/IP on VAX/VMS, VME/pSOS, FASTBUS/pSOS, and Unix systems. It includes plans to provide a portable, hardware independent implementation of TCP/IP based on Berkeley BSD software. 8 refs., 3 figs.

  20. IPS guidestar selection for stellar mode (ASTRO)

    NASA Technical Reports Server (NTRS)

    Mullins, Larry; Wooten, Lewis

    1988-01-01

    This report describes how guide stars are selected for the Optical Sensor Package (OSP) for the Instrument Pointing System (IPS) when it is operating in the stellar mode on the ASTRO missions. It also describes how the objective loads are written and how the various roll angles are related; i.e., the celestial roll or position angle, the objective load roll angles, and the IPS gimbal angles. There is a brief description of how the IPS operates and its various modes of operation; i.e., IDOP, IDIN, and OSPCAL.

  1. 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.

  2. The impact of beetle-induced conifer death on stand-scale canopy snow interception

    NASA Astrophysics Data System (ADS)

    Pugh, E. T.; Small, E. E.

    2011-12-01

    Snow that falls on a forest either passes through the canopy to the ground or is intercepted by the canopy on needles, branches or bark. The interception of snowfall in forest canopies impacts the water budget because intercepted snow is more likely to sublimate than subcanopy snow. Because forest canopy characteristics are a primary control of canopy snow interception, which in turn controls subcanopy snow accumulation, reductions in canopy density have important implications for snow accumulation on the forest floor. Forest structure can be drastically and rapidly altered by forest disturbance, such as insect attack, wildfire and blowdown. Here, we look at the impact that changing forest characteristics associated with beetle infestation have on canopy snow interception. The mountain pine beetle is currently impacting more than 100,000 km2 of pine forest in western North America. Trees killed by bark beetles eventually lose the majority of their canopy material. We hypothesize that tree death significantly reduces available interception platforms, leading to greater subcanopy snow accumulation than pre-infestation conditions. These potential impacts on snow accumulation are especially important for water resources in the western U.S., where the hydrologic cycle is dominated by snowmelt. We test this hypothesis using extensive data collected from adjacent living and grey phase dead stands. We employ multiple methods to measure canopy snow interception, at both the storm- and season-scales. During the winter of 2011, we made more than 10,000 spatially distributed measurements of subcanopy snow accumulation in three living and two dead lodgepole pine stands as well as three clearings. Measurements were made daily as well as immediately prior to and following storm events, allowing us to calculate storm-scale canopy interception. Interception is estimated by comparing subcanopy snow accumulation in clearings and forests. Additionally, by taking repeated daily

  3. Constituents from the bark of Tabebuia impetiginosa.

    PubMed

    Warashina, Tsutomu; Nagatani, Yoshimi; Noro, Tadataka

    2004-07-01

    The bark of Tabebuia impetiginosa afforded nineteen glycosides, consisting of four iridoid glycosides, two lignan glycosides, two isocoumarin glycosides, three phenylethanoid glycosides and eight phenolic glycosides. Their structures were determined using both spectroscopic and chemical methods. Iridoid glycosides, phenylethanoid glycosides and lignan glycosides had ajugol, osmanthuside H and secoisolariciresinol 4-O-beta-D-glucopyranoside as their structural elements, respectively, whereas the aglycone moieties of the isocoumarin glycosides were considered to be (-)-6-hydroxymellein. Phenolic glycosides had 4-methoxyphenol, 2,4-dimethoxyphenol, 3,4-dimethoxyphenol, 3,4,5-trimethoxyphenol and vanillyl 4-hydroxybenzoate as each aglycone moiety. Additionally, the sugar chains of these isocoumarin glycosides and phenolic glycosides were concluded to be beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside as well as those of osmanthuside H and above phenylethanoid glycosides.

  4. Antidepressant-Like Effects of Sanggenon G, Isolated from the Root Bark of Morus alba, in Rats: Involvement of the Serotonergic System.

    PubMed

    Lim, Dong Wook; Jung, Jae-Woo; Park, Ji-Hae; Baek, Nam-In; Kim, Yun Tai; Kim, In-Ho; Han, Daeseok

    2015-01-01

    The root bark of Morus alba is commonly used as an alternative medicine due to its numerous health benefits in humans. However, the antidepressant effects of various active components from M. alba have not been fully elucidated. In this study, we aimed to determine whether sanggenon G, an active compound isolated from the root bark of M. alba, exhibited antidepressant-like activity in rats subjected to forced swim test (FST)-induced depression. Acute treatment of rats with sanggenon G (30 mg/kg, intraperitoneally (i.p.)) significantly reduced immobility time and increased swimming time without any significant change in climbing. Rats treated with sanggenon G also exhibited a decrease in the limbic hypothalamic-pituitary-adrenal (HPA) axis response to the FST, as indicated by attenuation of the corticosterone response and decreased c-Fos immunoreactivity in the hypothalamic paraventricular nucleus (PVN). In addition, the antidepressant-like effects of sanggenon G were significantly inhibited by WAY100635 (1 mg/kg, i.p.; a selective 5-hydroxytryptamine1A (5-HT1A) receptor antagonist), but not SCH23390 (0.05 mg/kg, i.p.; a dopamine D1 receptor antagonist). Our findings suggested that the antidepressant-like effects of sanggenon G were mediated by an interaction with the serotonergic system. Further studies are needed to evaluate the potential of sanggenon G as an alternative therapeutic approach for the treatment of depression.

  5. MALDI-TOF MS analysis of condensed tannins with potent antioxidant activity from the leaf, stem bark and root bark of Acacia confusa.

    PubMed

    Wei, Shu-Dong; Zhou, Hai-Chao; Lin, Yi-Ming; Liao, Meng-Meng; Chai, Wei-Ming

    2010-06-15

    The structures of the condensed tannins from leaf, stem bark and root bark of Acacia confusa were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, and their antioxidant activities were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric reducing/antioxidant power (FRAP) assays. The results showed that the condensed tannins from stem bark and root bark include propelargonidin and procyanidin, and the leaf condensed tannins include propelargonidin, procyanidin and prodelphinidin, all with the procyanidin dominating. The condensed tannins had different polymer chain lengths, varying from trimers to undecamers for leaf and root bark and to dodecamers for stem bark. The condensed tannins extracted from the leaf, stem bark and root bark all showed a very good DPPH radical scavenging activity and ferric reducing power.

  6. 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...

  7. IP-1 Certification of Cargo Containers

    SciTech Connect

    Hagler, Lisle

    2010-10-05

    The purpose and scope of this engineering note is to demonstrate that the structural design of the cargo container complies with the IP-1 container requirements of 49 CFR 173.410 as required by CFR 173.411.

  8. Hypoglycaemic effect of Helicteres isora bark extract in rats.

    PubMed

    Kumar, G; Banu, G Sharmila; Murugesan, A G; Pandian, M Rajasekara

    2006-09-19

    The hypoglycaemic effect of the aqueous extract of the bark of Helicteres isora L. (Sterculiaceae) was investigated in normal, glucose load conditions and streptozotocin (STZ)-induced diabetic rats. In normal rats, the aqueous extract of the bark of Helicteres isora L. (100 and 200 mg/kg/p.o.) significantly (P<0.001) reduced the blood glucose levels from 64.5-48.5 and 67-47 mg% 2h after oral administration of bark extract and also significantly lowered the blood glucose in STZ diabetic rats from 68-105 and 66-85.5 mg% 21 days after daily oral administration of the extract (P<0.001). The results suggested that the aqueous extract of bark of Helicteres isora L. possesses a potential hypoglycaemic effect in diabetic rats.

  9. 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...

  10. BOREAS TE-8 Aspen Bark Spectral Reflectance Data

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Papagno, Andrea (Editor); Spencer, Shannon L.; Rock, Barrett N.

    2000-01-01

    The BOREAS TE-08 team collected in-lab spectral reflectance data for aspen bark and leaves from three sites within the BOREAS SSA from 24-May-1994 to 16-Jun-1994 (IFC 1), 19-Jul-1994 to 08-Aug-1994 (IFC 2), and 30-Aug-1994 to 19-Sep-1994 (IFC 3). One to nine trees from each site were sampled during the three IFCs. Each tree was sampled in five different locations for bark spectral properties: BS, US, BR, BT, and BO. Additionally, a limited number of LV were collected. Bark samples were removed from the stem of the tree and placed in ziplock bags for transport to UNH, where they were scanned with a spectroradiometer in a controlled environment. Each sample was scanned twice: the first set of measurements was made with the bark surface moistened, and the second set was made with the bark surface air-dried for a period of 30 minutes. These data represent continuous spectra of bark reflectance. Each sample was scanned three times, rotating the sample when possible. The reported values for each sample are an average over the three scans. The data are provided in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC).

  11. DNA Extraction and Amplification from Contemporary Polynesian Bark-Cloth

    PubMed Central

    Moncada, Ximena; Payacán, Claudia; Arriaza, Francisco; Lobos, Sergio; Seelenfreund, Daniela; Seelenfreund, Andrea

    2013-01-01

    Background Paper mulberry has been used for thousands of years in Asia and Oceania for making paper and bark-cloth, respectively. Museums around the world hold valuable collections of Polynesian bark-cloth. Genetic analysis of the plant fibers from which the textiles were made may answer a number of questions of interest related to provenance, authenticity or species used in the manufacture of these textiles. Recovery of nucleic acids from paper mulberry bark-cloth has not been reported before. Methodology We describe a simple method for the extraction of PCR-amplifiable DNA from small samples of contemporary Polynesian bark-cloth (tapa) using two types of nuclear markers. We report the amplification of about 300 bp sequences of the ITS1 region and of a microsatellite marker. Conclusions Sufficient DNA was retrieved from all bark-cloth samples to permit successful PCR amplification. This method shows a means of obtaining useful genetic information from modern bark-cloth samples and opens perspectives for the analyses of small fragments derived from ethnographic materials. PMID:23437166

  12. Research note: the effects of darkling beetles on broiler performance.

    PubMed

    Skewes, P A; Monroe, J L

    1991-04-01

    Six polyvinylchlorine pipe darkling beetle traps were placed in 20 commercial broiler production facilities, and the relative level of beetle infestation was determined from weekly sampling during 4 wk of the growout period. The average number of beetles found at each facility was compared with the following production parameters: mortality, feed conversion, condemnation rate, and production cost. In the 20 commercial broiler flocks evaluated, the level of darkling beetles within the facility was not related to any of the production parameters measured.

  13. Management, morphological, and environmental factors influencing Douglas-fir bark furrows in the Oregon Coast Range

    USGS Publications Warehouse

    Sheridan, Christopher D.; Puettmann, Klaus J.; Huso, Manuela M.P.; Hagar, Joan C.; Falk, Kristen R.

    2013-01-01

    Many land managers in the Pacific Northwest have the goal of increasing late-successional forest structures. Despite the documented importance of Douglas-fir tree bark structure in forested ecosystems, little is known about factors influencing bark development and how foresters can manage development. This study investigated the relative importance of tree size, growth, environmental factors, and thinning on Douglas-fir bark furrow characteristics in the Oregon Coast Range. Bark furrow depth, area, and bark roughness were measured for Douglas-fir trees in young heavily thinned and unthinned sites and compared to older reference sites. We tested models for relationships between bark furrow response and thinning, tree diameter, diameter growth, and environmental factors. Separately, we compared bark responses measured on trees used by bark-foraging birds with trees with no observed usage. Tree diameter and diameter growth were the most important variables in predicting bark characteristics in young trees. Measured environmental variables were not strongly related to bark characteristics. Bark furrow characteristics in old trees were influenced by tree diameter and surrounding tree densities. Young trees used by bark foragers did not have different bark characteristics than unused trees. Efforts to enhance Douglas-fir bark characteristics should emphasize retention of larger diameter trees' growth enhancement.

  14. 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...

  15. 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...

  16. Water-deficit and fungal infection can differentially affect the production of different classes of defense compounds in two host pines of mountain pine beetle.

    PubMed

    Erbilgin, Nadir; Cale, Jonathan A; Lusebrink, Inka; Najar, Ahmed; Klutsch, Jennifer G; Sherwood, Patrick; Enrico Bonello, Pierluigi; Evenden, Maya L

    2016-11-22

    Bark beetles are important agents of tree mortality in conifer forests and their interaction with trees is influenced by host defense chemicals, such as monoterpenes and phenolics. Since mountain pine beetle (Dendroctonus ponderosae Hopkins) has expanded its host range from lodgepole pine (Pinus contorta Doug. ex Loud. (var. latifolia Engelm.))-dominated forests to the novel jack pine (Pinus banksiana Lamb.) forests in western Canada, studies investigating the jack pine suitability as a host for this beetle have exclusively focused on monoterpenes, and whether phenolics affect jack pine suitability to mountain pine beetle and its symbiotic fungus Grosmannia clavigera is unknown. We investigated the phenolic and monoterpene composition in phloem and foliage of jack and lodgepole pines, and their subsequent change in response to water deficit and G. clavigera inoculation treatments. In lodgepole pine phloem, water deficit treatment inhibited the accumulation of both the total and richness of phenolics, but had no effect on total monoterpene production or richness. Fungal infection also inhibited the total phenolic production and had no effect on phenolic or monoterpene richness, but increased total monoterpene synthesis by 71%. In jack pine phloem, water deficit treatment reduced phenolic production, but had no effect on phenolic or monoterpene richness or total monoterpenes. Fungal infection did not affect phenolic or monoterpene production. Lesions of both species contained lower phenolics but higher monoterpenes than non-infected phloem in the same tree. In both species, richness of monoterpenes and phenolics was greater in non-infected phloem than in lesions. We conclude that monoterpenes seem to be a critical component of induced defenses against G. clavigera in both jack and lodgepole pines; however, a lack of increased monoterpene response to fungal infection is an important evolutionary factor defining jack pine suitability to the mountain pine beetle

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. Antioxidative compounds from Garcinia buchananii stem bark.

    PubMed

    Stark, Timo D; Salger, Mathias; Frank, Oliver; Balemba, Onesmo B; Wakamatsu, Junichiro; Hofmann, Thomas

    2015-02-27

    An aqueous ethanolic extract of the stem bark of Garcinia buchananii showed strong antioxidative activity using H2O2 scavenging, oxygen radical absorbance capacity (ORAC), and Trolox equivalent antioxidant capacity (TEAC) assays. Activity-guided fractionation afforded three new compounds, isomanniflavanone (1), an ent-eriodictyol-(3α→6)-dihydroquercetin-linked biflavanone, 1,5-dimethoxyajacareubin (2), and the depsidone garcinisidone-G (3), and six known compounds, (2″R,3″R)-preussianon, euxanthone, 2-isoprenyl-1,3,5,6-tetrahydroxyxanthone, jacareubin, isogarcinol, and garcinol. All compounds were described for the first time in Garcinia buchananii. The absolute configurations were determined by a combination of NMR, ECD spectroscopy, and polarimetry. These natural products showed high in vitro antioxidative power, especially isomanniflavanone, with an EC50 value of 8.5 μM (H2O2 scavenging), 3.50/4.95 mmol TE/mmol (H/L-TEAC), and 7.54/14.56 mmol TE/mmol (H/L-ORAC).

  2. A survey of IP over ATM architectures

    SciTech Connect

    Chen, H.; Tsang, R.; Brandt, J.; Hutchins, J.

    1997-07-01

    Over the past decade, the Internet has burgeoned into a worldwide information highway consisting of approximately 5 million hosts on over 45,000 interconnected networks. This unprecedented growth, together with the introduction of multimedia workstations, has spurred the development of innovative applications that require high speed, low latency, and real-time transport. Today`s Internet can neither scale in its bandwidth nor guarantee the Quality of Services (QoS) necessary to meet these performance requirements. Many network researchers propose to use the Asynchronous Transfer Mode (ATM) technology as the underlying infrastructure for the next generation of workgroup, campus, and enterprise IP networks. Since ATM is significantly different from today`s legacy network technologies, efficient implementation of IP over ATM is especially challenging. This tutorial paper covers several existing proposals that integrate IP over ATM.

  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. Bark flammability as a fire-response trait for subalpine trees

    PubMed Central

    Frejaville, Thibaut; Curt, Thomas; Carcaillet, Christopher

    2013-01-01

    Relationships between the flammability properties of a given plant and its chances of survival after a fire still remain unknown. We hypothesize that the bark flammability of a tree reduces the potential for tree survival following surface fires, and that if tree resistance to fire is provided by a thick insulating bark, the latter must be few flammable. We test, on subalpine tree species, the relationship between the flammability of bark and its insulating ability, identifies the biological traits that determine bark flammability, and assesses their relative susceptibility to surface fires from their bark properties. The experimental set of burning properties was analyzed by Principal Component Analysis to assess the bark flammability. Bark insulating ability was expressed by the critical time to cambium kill computed from bark thickness. Log-linear regressions indicated that bark flammability varies with the bark thickness and the density of wood under bark and that the most flammable barks have poor insulating ability. Susceptibility to surface fires increases from gymnosperm to angiosperm subalpine trees. The co-dominant subalpine species Larix decidua (Mill.) and Pinus cembra (L.) exhibit large differences in both flammability and insulating ability of the bark that should partly explain their contrasted responses to fires in the past. PMID:24324473

  5. Ground beetles of the Ukraine (Coleoptera, Carabidae).

    PubMed

    Putchkov, Alexander

    2011-01-01

    A review of the ground beetles of the Ukrainian fauna is given. Almost 750 species from 117 genera of Carabidae are known to occur in the Ukraine. Approximately 450 species of ground beetles are registered in the Carpathian region. No less than 300 species of ground beetles are found in the forest zone. Approximately 400 species of Carabidae present in the forest-steppe zone are relatively similar in species composition to those in the forest territories. Some 450 species of Carabidae are inhabitants of the steppe zone. Representatives of many other regions of heterogeneous biotopes such as forest, semi desert, intrazonal, etc. can be found in the steppe areas. The fauna of Carabidae (ca. 100 species) of the lowlands of southern Ukraine (sandy biotopes), situated mostly in the Kherson region, is very peculiar. The fauna of the Crimean mountains contains about 300 species. Conservation measures for the Carabidae are discussed.

  6. Ground beetles of the Ukraine (Coleoptera, Carabidae)

    PubMed Central

    Putchkov, Alexander

    2011-01-01

    Abstract A review of the ground beetles of the Ukrainian fauna is given. Almost 750 species from 117 genera of Carabidae are known to occur in the Ukraine. Approximately 450 species of ground beetles are registered in the Carpathian region. No less than 300 species of ground beetles are found in the forest zone. Approximately 400 species of Carabidae present in the forest-steppe zone are relatively similar in species composition to those in the forest territories. Some 450 species of Carabidae are inhabitants of the steppe zone. Representatives of many other regions of heterogeneous biotopes such as forest, semi desert, intrazonal, etc. can be found in the steppe areas. The fauna of Carabidae (ca. 100 species) of the lowlands of southern Ukraine (sandy biotopes), situated mostly in the Kherson region, is very peculiar. The fauna of the Crimean mountains contains about 300 species. Conservation measures for the Carabidae are discussed. PMID:21738430

  7. IP-RFID Based Container Monitoring System

    NASA Astrophysics Data System (ADS)

    Choi, Hyung-Rim; Park, Byung-Kwon; Park, Yong-Sung; Lee, Chang-Sup; Park, Chang-Hyun

    RFID technology in container management field is considered for increasing productivity and efficiency in logistics industry. But there are a lot of problems caused by inappropriate application of RFID technology in shipping logistics. Therefore, technology development based on IP is needed for accepting diverse technology applied before and offering better service to develop container management technology involved with RFID. In this study, realtime container monitoring system using IP-RFID is designed and implemented for supplementing weakness of information gathering using existing RFID and transferring data in real time to user.

  8. Space-Based Voice over IP Networks

    NASA Technical Reports Server (NTRS)

    Nguyen, Sam P.; Okino, Clayton; Walsh, William; Clare, Loren

    2007-01-01

    In human space exploration missions (e.g. a return to the Moon and for future missions to Mars), there will be a need to provide voice communications services. In this work we focus on the performance of Voice over IP (VoIP) techniques applied to space networks, where long range latencies, simplex links, and significant bit error rates occur. Link layer and network layer overhead issues are examined. Finally, we provide some discussion on issues related to voice conferencing in the space network environment.

  9. Dung beetles and fecal helminth transmission: patterns, mechanisms and questions.

    PubMed

    Nichols, Elizabeth; Gómez, Andrés

    2014-04-01

    Dung beetles are detrivorous insects that feed on and reproduce in the fecal material of vertebrates. This dependency on vertebrate feces implies frequent contact between dung beetles and parasitic helminths with a fecal component to their life-cycle. Interactions between dung beetles and helminths carry both positive and negative consequences for successful parasite transmission, however to date there has been no systematic review of dung beetle-helminth interactions, their epidemiological importance, or their underlying mechanisms. Here we review the observational evidence of beetle biodiversity-helminth transmission relationships, propose five mechanisms by which dung beetles influence helminth survival and transmission, and highlight areas for future research. Efforts to understand how anthropogenic impacts on biodiversity may influence parasite transmission must include the development of detailed, mechanistic understanding of the multiple interactions between free-living and parasitic species within ecological communities. The dung beetle-helminth system may be a promising future model system with which to understand these complex relationships.

  10. Utilization of flavonoid compounds from bark and wood: a review.

    PubMed

    Yazaki, Yoshikazu

    2015-03-01

    Flavonoid compounds, which are extracted from bark and wood and used commercially, are flavan 3-ols as monomers and their polymers, which are called "condensed tannins". Reactions of the condensed tannins with formaldehyde are the basis for wood adhesives. In the late 1940s, tannin research for wood adhesives was begun and the world-first commercial use of wattle tannin from black wattle (Acacia mearnsii) bark as wood adhesives occurred in Australia in the 1960s. In addition, wattle tannin-based adhesives were further developed in South Africa and the uses of these adhesives have been continuing to date. The success of wattle tannin in wood adhesives is demonstrated by the collaboration of the ACIAR with the CAF in the early 1990s. Although radiata pine bark (Pinus radiata) could be a useful resource for the production of wood adhesives, three problems prevented its use in this application: low extractive yields from the bark, variable quality of the tannin extracts and excessive viscosity of the formulated tannin adhesives. In order to overcome these problems, various extraction methods have been proposed. Studies on tannin adhesives from bark of other pine species are also described. Furthermore, the use of the tannin in the bark without extraction is described as "bark adhesives" from radiata pine and black wattle. The use of radiata tannin without formaldehyde for moulded wood products is also described. Owing to the strong antioxidant activity of flavonoid compounds, bark extracts from French maritime pine (Pinus pinaster, synonym P. maritima) and radiata pine have been commercialized as nutritional supplements: Pycnogenol and Enzogenol, respectively. The background and the development of Pycnogenol and the basic difference in the preparation processes between Pycnogenol and Enzogenol are described. On the basis of the discovery that the SOSA value for wattle tannin is approximately 10 times that of extracts from pine bark supplements (Pycnogenol and Enzogenol

  11. Hepatoprotective activity of Mammea africana ethanol stem bark extract

    PubMed Central

    Okokon, Jude Efiom; Bawo, Michael Burata; Mbagwu, Herbert Orji

    2016-01-01

    Objective: The stem bark of Mammea africana Sabine (Guttiferae), (M. africana) a common plant that has been traditionally used to treat various diseases and ailments was evaluated for hepatoprotective potentials against paracetamol-induced liver injury in rats. Materials and Methods: The hepatoprotective effect of the stem bark extract (30-90 mg/kg) was evaluated by the assay of liver function parameters, namely total and direct bilirubin, serum protein and albumin, total cholesterol, alanine aminotransaminase (ALT), aspartate aminotransaminase (AST), and alkaline phosphatase activities (ALP), antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH) and histopathological study of the liver. Results: Administration of the stem bark extract caused a significant (p<0.05 – 0.001) dose-dependent reduction of high levels of liver enzymes (ALT, AST and ALP), total cholesterol, direct and total bilirubin as well as elevation of serum levels of total protein, albumin and antioxidant enzymes (SOD, CAT, GPx and GSH). Histology of the liver sections of extract and silymarin-treated animals showed reductions in the pathological features compared to the paracetamol-treated animals. The chemical pathological changes were consistent with histopathological observations suggesting marked hepatoprotective effect of the stem bark extract of M. africana. Conclusion: The results show that the stem bark extract of M. africana has hepatoprotective potential which may be due to its antioxidant activity. PMID:27222838

  12. Efficacy and Safety of White Willow Bark (Salix alba) Extracts.

    PubMed

    Shara, Mohd; Stohs, Sidney J

    2015-08-01

    Willow bark extract has been used for thousands of years as an anti-inflammatory, antipyretic, and analgesic. In spite of its long history of use, relatively few human and animal studies have been published that confirm anecdotal observations. A small number of clinical studies have been conducted that support the use of willow bark extracts in chronic lower back and joint pain and osteoarthritis. Willow bark extracts also are widely used in sports performance and weight loss products presumably because of anti-inflammatory and analgesic activities, although no human studies have been published that specifically and directly document beneficial effects. In recent years, various in vitro and animal studies have demonstrated that the anti-inflammatory activity of willow bark extract is associated with down regulation of the inflammatory mediators tumor necrosis factor-α and nuclear factor-kappa B. Although willow bark extracts are generally standardized to salicin, other ingredients in the extracts including other salicylates as well as polyphenols, and flavonoids may also play prominent roles in the therapeutic actions. Adverse effects appear to be minimal as compared to non-steroidal anti-inflammatory drugs including aspirin. The primary cause for concern may relate to allergic reactions in salicylate-sensitive individuals.

  13. Reducing hazardous heavy metal ions using mangium bark waste.

    PubMed

    Khabibi, Jauhar; Syafii, Wasrin; Sari, Rita Kartika

    2016-08-01

    The objective of this study was to evaluate the characteristics of mangium bark and its biosorbent ability to reduce heavy metal ions in standard solutions and wastewater and to assess changes in bark characteristics after heavy metal absorption. The experiments were conducted to determine heavy metal absorption from solutions of heavy metals alone and in mixtures as well as from wastewater. The results show that mangium bark can absorb heavy metals. Absorption percentages and capacities from single heavy metal solutions showed that Cu(2+) > Ni(2+) > Pb(2+) > Hg(2+), while those from mixture solutions showed that Hg(2+) > Cu(2+) > Pb(2+) > Ni(2+). Wastewater from gold mining only contained Cu, with an absorption percentage and capacity of 42.87 % and 0.75 mg/g, respectively. The highest absorption percentage and capacity of 92.77 % and 5.18 mg/g, respectively, were found for Hg(2+) in a mixture solution and Cu(2+) in single-metal solution. The Cu(2+) absorption process in a single-metal solution changed the biosorbent characteristics of the mangium bark, yielding a decreased crystalline fraction; changed transmittance on hydroxyl, carboxyl, and carbonyl groups; and increased the presence of Cu. In conclusion, mangium bark biosorbent can reduce hazardous heavy metal ions in both standard solutions and wastewater.

  14. Antioxidant Potential of Bark Extracts from Boreal Forest Conifers

    PubMed Central

    Legault, Jean; Girard-Lalancette, Karl; Dufour, Dominic; Pichette, André

    2013-01-01

    The bark of boreal forest conifers has been traditionally used by Native Americans to treat various ailments and diseases. Some of these diseases involve reactive oxygen species (ROS) that can be prevented by the consumption of antioxidants such as phenolic compounds that can be found in medicinal plants. In this study, ultrasonic assisted extraction has been performed under various solvent conditions (water:ethanol mixtures) on the bark of seven boreal forest conifers used by Native Americans including: Pinus strobus, Pinus resinosa, Pinus banksiana, Picea mariana, Picea glauca, Larix laricina, and Abies balsamea. The total phenolic content, as well as ORACFL potency and cellular antioxidant activity (IC50), were evaluated for all bark extracts, and compared with the standardized water extract of Pinus maritima bark (Pycnogenol), which showed clinical efficiency to prevent ROS deleterious effects. The best overall phenolic extraction yield and antioxidant potential was obtained with Picea glauca and Picea mariana. Interestingly, total phenolic content of these bark extracts was similar to Pycnogenol but their antioxidant activity were higher. Moreover, most of the extracts did not inhibit the growth of human skin fibroblasts, WS1. A significant correlation was found between the total phenolic content and the antioxidant activity for water extracts suggesting that these compounds are involved in the activity. PMID:26784337

  15. Antioxidant Potential of Bark Extracts from Boreal Forest Conifers.

    PubMed

    Legault, Jean; Girard-Lalancette, Karl; Dufour, Dominic; Pichette, André

    2013-07-11

    The bark of boreal forest conifers has been traditionally used by Native Americans to treat various ailments and diseases. Some of these diseases involve reactive oxygen species (ROS) that can be prevented by the consumption of antioxidants such as phenolic compounds that can be found in medicinal plants. In this study, ultrasonic assisted extraction has been performed under various solvent conditions (water:ethanol mixtures) on the bark of seven boreal forest conifers used by Native Americans including: Pinus strobus, Pinus resinosa, Pinus banksiana, Picea mariana, Picea glauca, Larix laricina, and Abies balsamea. The total phenolic content, as well as ORACFL potency and cellular antioxidant activity (IC50), were evaluated for all bark extracts, and compared with the standardized water extract of Pinus maritima bark (Pycnogenol), which showed clinical efficiency to prevent ROS deleterious effects. The best overall phenolic extraction yield and antioxidant potential was obtained with Picea glauca and Picea mariana. Interestingly, total phenolic content of these bark extracts was similar to Pycnogenol but their antioxidant activity were higher. Moreover, most of the extracts did not inhibit the growth of human skin fibroblasts, WS1. A significant correlation was found between the total phenolic content and the antioxidant activity for water extracts suggesting that these compounds are involved in the activity.

  16. Using Quasi-Dynamic Land Cover to Investigate Hydrologic Disturbance from Beetle-kill and Dust in the Upper Colorado River Basin

    NASA Astrophysics Data System (ADS)

    Livneh, B.; Deems, J. S.; Buma, B.; Barsugli, J. J.

    2013-12-01

    Since 2002, the headwaters of the Colorado River Basin have experienced changes in land cover, occurring at sub-annual timescales. Widespread tree mortality from bark beetle infestation has taken place across a range of forest types, elevation, and latitude. Extent and severity of forest structure alteration have been observed through a combination of aerial survey data, MODIS-derived leaf area index (LAI), and in situ measurements. Additional disturbance has resulted from deposition of dust from regional dryland sources on mountain snowpacks that strongly alter the snow surface albedo, driving earlier and faster snowmelt runoff. Severity of dust-on-snow events have been estimated via satellite, field, and in-situ observations. In this study, we explore the combined impacts of forest disturbance and dust on snow within a hydrologic modeling framework. We force the Distributed Hydrology and Vegetation Model (DHSVM) with observed meteorology, time-varying maps of forest properties to emulate bark beetle impacts, and variable parameterizations of snow albedo based on dust events. Preliminary results from beetle-killed canopy alteration suggest slightly greater snow accumulation as a result of less snow interception and reduced canopy sublimation, which outweigh increases in sub-canopy snow ablation fluxes. The primary hydrologic control of dust-on-snow events is on the rate of snowmelt, with more rapid melt rates associated with more extreme dust deposition. The use of a process-based model at relatively fine spatial scales (~100m) together with quasi-dynamic vegetation and snow properties is expected to provide new insights into the mechanisms driving disturbance related hydrologic impacts and better inform mitigation strategies.

  17. Toxicity of the Essential Oil of Illicium difengpi Stem Bark and Its Constituent Compounds Towards Two Grain Storage Insects

    PubMed Central

    Sha Chu, Sha; Fang Wang, Cheng; Shan Du, Shu; Liang Liu, Shao; Long Liu, Zhi

    2011-01-01

    During our screening program for new agrochemicals from Chinese medicinal herbs, the essential oil of Illicium difengpi stem bark was found to possess strong insecticidal activities against the maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae) and red flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae). A total of 37 components of the essential oil of I. difengpi were identified. The main components of the essential oil were safrole (23.61%), linalool (12.93%), and germacrene D (5.35%). Bioactivities-directed chromatographic separation on repeated silica gel columns led to the isolation of two compounds: safrole and linalool. Safrole showed pronounced contact toxicity against both insect species and (LD50 = 8.54 for S. zeamais; 4.67 µg/adult for T. castaneum) and was more toxic than linalool (LD50 = 24.88 for S. zeamais; 8.12 µg/adult for T. castaneum). The essential oil acting against the two species of insects showed LD50 values of 13.83 and 6.33 µg/adult, respectively. Linalool also possessed strong fumigant toxicity against both insect species (LC50 = 10.02 for S. zeamais; 9.34 mg/L for T. castaneum) and was more toxic than safrole (LD50 = 32.96 and 38.25 mg/L), while the crude essential oil acting against the two species of insects showed LC50 values of 14.62 and 16.22 mg/L, respectively. These results suggest that the essential oil of I. difengpi stem bark and the two compounds may be used in grain storage to combat insect pests. PMID:22236213

  18. Toxicity of the essential oil of Illicium difengpi stem bark and its constituent compounds towards two grain storage insects.

    PubMed

    Chu, Sha Sha; Wang, Cheng Fang; Du, Shu Shan; Liu, Shao Liang; Liu, Zhi Long

    2011-01-01

    During our screening program for new agrochemicals from Chinese medicinal herbs, the essential oil of Illicium difengpi stem bark was found to possess strong insecticidal activities against the maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae) and red flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae). A total of 37 components of the essential oil of I. difengpi were identified. The main components of the essential oil were safrole (23.61%), linalool (12.93%), and germacrene D (5.35%). Bioactivities-directed chromatographic separation on repeated silica gel columns led to the isolation of two compounds: safrole and linalool. Safrole showed pronounced contact toxicity against both insect species and (LD₅₀ = 8.54 for S. zeamais; 4.67 µg/adult for T. castaneum) and was more toxic than linalool (LD₅₀ = 24.88 for S. zeamais; 8.12 µg/adult for T. castaneum). The essential oil acting against the two species of insects showed LD₅₀ values of 13.83 and 6.33 µg/adult, respectively. Linalool also possessed strong fumigant toxicity against both insect species (LC₅₀ = 10.02 for S. zeamais; 9.34 mg/L for T. castaneum) and was more toxic than safrole (LD₅₀ = 32.96 and 38.25 mg/L), while the crude essential oil acting against the two species of insects showed LC₅₀ values of 14.62 and 16.22 mg/L, respectively. These results suggest that the essential oil of I. difengpi stem bark and the two compounds may be used in grain storage to combat insect pests.

  19. A small animal model study of perlite and fir bark dust on guinea pig lungs.

    PubMed

    McMichael, R F; DiPalma, J R; Blumenstein, R; Amenta, P S; Freedman, A P; Barbieri, E J

    1983-05-01

    Fir bark (Abies) and perlite (noncrystalline silicate) dusts have been reported to cause pulmonary disease in humans. Guinea pigs were exposed to either fir bark or perlite dust in a special chamber. Severe pathologic changes occurred in the lungs, consisting of lymphoid aggregated and a perivascular inflammatory response. Both dusts caused similar changes although one was vegetable (fir bark) and the other mineral (perlite). Fir bark and perlite dust appeared to be more than just nuisance dusts.

  20. 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

  1. EQuIP-ped for Success

    ERIC Educational Resources Information Center

    Ewing, Molly

    2015-01-01

    The Educators Evaluating the Quality of Instructional Products (EQuIP) Rubric for science is a new tool for science educators that provides criteria by which to examine the alignment and overall quality of lessons and units with respect to the "Next Generation Science Standards" ("NGSS"). The rubric criteria are divided into…

  2. Is VoIP Worth It?

    ERIC Educational Resources Information Center

    Schaffhauser, Dian

    2008-01-01

    School districts have by and large had great results implementing VoIP, which has become the conduit for delivering expanded functionality, achieving greater internal control, and gaining freedom from onerous monthly phone bills. But demonstrating a financial return on what is a substantial investment can be an elusive effort. The goal of…

  3. How To: Be VoIP-Savvy

    ERIC Educational Resources Information Center

    Branzburg, Jeffrey

    2005-01-01

    Cablevision, Comcast, Verizon, and many other high-speed broadband Internet providers are now also offering telephone services through "Voice over Internet Protocol" (VoIP). This technology sends ordinary telephone calls over the Internet rather than over telephone lines. While impractical without the use of a broadband Internet connection, with…

  4. 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

  5. Factors controlling bark decomposition and its role in wood decomposition in five tropical tree species.

    PubMed

    Dossa, Gbadamassi G O; Paudel, Ekananda; Cao, Kunfang; Schaefer, Douglas; Harrison, Rhett D

    2016-10-04

    Organic matter decomposition represents a vital ecosystem process by which nutrients are made available for plant uptake and is a major flux in the global carbon cycle. Previous studies have investigated decomposition of different plant parts, but few considered bark decomposition or its role in decomposition of wood. However, bark can comprise a large fraction of tree biomass. We used a common litter-bed approach to investigate factors affecting bark decomposition and its role in wood decomposition for five tree species in a secondary seasonal tropical rain forest in SW China. For bark, we implemented a litter bag experiment over 12 mo, using different mesh sizes to investigate effects of litter meso- and macro-fauna. For wood, we compared the decomposition of branches with and without bark over 24 mo. Bark in coarse mesh bags decomposed 1.11-1.76 times faster than bark in fine mesh bags. For wood decomposition, responses to bark removal were species dependent. Three species with slow wood decomposition rates showed significant negative effects of bark-removal, but there was no significant effect in the other two species. Future research should also separately examine bark and wood decomposition, and consider bark-removal experiments to better understand roles of bark in wood decomposition.

  6. Relative density, equilibrium moisture content, and dimensional stability of western hemlock bark

    SciTech Connect

    Meyer, R.W.; Kellogg, R.M.; Warren, W.G.

    1980-04-01

    The measurement of western hemlock bark samples from three coastal sites in British Columbia revealed that inner bark relative density (0.382) is less than that of the adjacent sapwood (0.413) and markedly less than that of outer bark (0.463). The equilibrium moisture content of the inner and outer bark are equivalent at both 70 and 30% relative humidity, and slightly higher than that of the sapwood. The generally higher shrinkage of bark compared with wood is the result of bark cell collapse during drying. In the outer bark, some collapse or crushing takes place in the standing tree. This compacting of tissue reduces the shrinkage of outer bark relative to the inner bark. The actual shrinkage per unit change in moisture content of the inner bark is the same as that for the sapwood. The outer bark appears to be more dimensionally stable. The longitudinal shrinkage of both inner (2.9%) and outer (2.2%) bark is markedly greater than that of the sapwood (0.1-0.2%). (Refs. 10).

  7. Factors controlling bark decomposition and its role in wood decomposition in five tropical tree species

    PubMed Central

    Dossa, Gbadamassi G. O.; Paudel, Ekananda; Cao, Kunfang; Schaefer, Douglas; Harrison, Rhett D.

    2016-01-01

    Organic matter decomposition represents a vital ecosystem process by which nutrients are made available for plant uptake and is a major flux in the global carbon cycle. Previous studies have investigated decomposition of different plant parts, but few considered bark decomposition or its role in decomposition of wood. However, bark can comprise a large fraction of tree biomass. We used a common litter-bed approach to investigate factors affecting bark decomposition and its role in wood decomposition for five tree species in a secondary seasonal tropical rain forest in SW China. For bark, we implemented a litter bag experiment over 12 mo, using different mesh sizes to investigate effects of litter meso- and macro-fauna. For wood, we compared the decomposition of branches with and without bark over 24 mo. Bark in coarse mesh bags decomposed 1.11–1.76 times faster than bark in fine mesh bags. For wood decomposition, responses to bark removal were species dependent. Three species with slow wood decomposition rates showed significant negative effects of bark-removal, but there was no significant effect in the other two species. Future research should also separately examine bark and wood decomposition, and consider bark-removal experiments to better understand roles of bark in wood decomposition. PMID:27698461

  8. Depositional characteristics of atmospheric polybrominated diphenyl ethers on tree barks

    PubMed Central

    Chun, Man Young

    2014-01-01

    Objectives This study was conducted to determine the depositional characteristics of several tree barks, including Ginkgo (Ginkgo biloba), Pine (Pinus densiflora), Platanus (Platanus), and Metasequoia (Metasequoia glyptostroboides). These were used as passive air sampler (PAS) of atmospheric polybrominated diphenyl ethers (PBDEs). Methods Tree barks were sampled from the same site. PBDEs were analyzed by highresolution gas chromatography/high-resolution mass spectrometer, and the lipid content was measured using the gravimetric method by n-hexane extraction. Results Gingko contained the highest lipid content (7.82 mg/g dry), whereas pine (4.85 mg/g dry), Platanus (3.61 mg/g dry), and Metasequoia (0.97 mg/g dry) had relatively lower content. The highest total PBDEs concentration was observed in Metasequoia (83,159.0 pg/g dry), followed by Ginkgo (53,538.4 pg/g dry), Pine (20,266.4 pg/g dry), and Platanus (12,572.0 pg/g dry). There were poor correlations between lipid content and total PBDE concentrations in tree barks (R2=0.1011, p =0.682). Among the PBDE congeners, BDE 206, 207 and 209 were highly brominated PBDEs that are sorbed to particulates in ambient air, which accounted for 90.5% (84.3-95.6%) of the concentration and were therefore identified as the main PBDE congener. The concentrations of particulate PBDEs deposited on tree barks were dependent on morphological characteristics such as surface area or roughness of barks. Conclusions Therefore, when using the tree barks as the PAS of the atmospheric PBDEs, samples belonging to same tree species should be collected to reduce errors and to obtain reliable data. PMID:25116365

  9. (BOREAS) BOREAS TE-8 Aspen Bark Chemistry Data

    NASA Technical Reports Server (NTRS)

    Hall, Forrest G. (Editor); Papagno, Andrea (Editor); Spencer, Shannon L.; Rock, Barrett N.

    2000-01-01

    The BOREAS TE-8 team collected pigment density data from aspen bark and leaves from four sites within the BOREAS SSA from 24-May-1994 to 16-Jun-1994 (IFC-1), 19-Jul-1994 to 08-Aug- 1994 (IFC-2), and 30-Aug-1994 to 19-Sep-1994 (IFC-3). One to nine trees from each site were sampled during the three IFCs. Each tree was sampled in five different locations for bark pigment properties: basal stem section, which was any bark sample taken below one-half the tree height; upper stem section, which was any bark sample taken from the main stem above one-half the tree height; bark taken from branches up to 3 years old; a 2-year-old branch segment, and a 1-year-old branch segment. Additionally, a limited number of leaves were collected. Bark samples were removed from the stem of the tree, placed in ziplock bags, and transported to UNH, where they were processed and analyzed by a spectrophotometer. In each data file, samples are identified by Site, Date, Tree#, and Sample Location (see I st paragraph above. Pigment density values are normalized to mg/m2. Density values for the following pigments are provided: Chi a, Chi b, Total Chi (Chi a+b), Carotenoids, Chi a to b ratio, and the Total Chi to carotenoids ratio. The data are stored in ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distrobuted Activity Archive Center (DAAC).

  10. The Utilization of Bark to Make Rigid Polyurethane Foams

    NASA Astrophysics Data System (ADS)

    D'Souza, Jason

    This work focused on the characterization of polyols derived from the liquefaction or alkoxylation of bark. Regarding liquefaction, it was found that both temperature and solvent structure played a significant role in polyol properties. High temperature liquefaction resulted in the degradation of sugars, while liquefaction at mild temperatures preserved sugar structures as shown by 31P-NMR. It was also shown that liquefaction at 130°C was ideal in terms of producing a polyol with a relatively at, broad, plateau of molecular weight distribution, whereas liquefaction at 90 and 160°C produced polyols with a large amount of low molecular weight compounds. Regarding solvent structure, it was found that polyhydric alcohols with short chain primary hydroxyls resulted in less sugar degradation products and less formation of condensation side-products. It is proposed that the highly polar environment promoted grafting and prevented condensation onto other biopolymers. Using organic solvents it was found that ketonic solvents like acetyl acetone and cyclohexanone, through their highly polar carbonyl group could engage in hydrogen bonding through electron donation/proton accepting interactions. These enabled the solvent to reduce the amount of condensation reactions and improve liquefaction yield. The liquefied bark-based polyols were then used to make polyurethane foams. It was found that when a diversity of hydroxyl groups were present the foaming rate was reduced and this may react a slower rate of curing and explain why the bark foams had a greater amount of cells that underwent coalescence. It was also observed that the bark foams had a low amount of closed-cell content. Since closed-cell content plays a role in dictating elastic compression, this may explain why the bark foams exhibited a lower elastic modulus. Finally, as a contrast to liquefaction, bark was alkoxylated. It was observed that the conversion yield was higher than liquefaction. The polyols had a high

  11. 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...

  12. Cuticle formation and pigmentation in beetles.

    PubMed

    Noh, Mi Young; Muthukrishnan, Subbaratnam; Kramer, Karl J; Arakane, Yasuyuki

    2016-10-01

    Adult beetles (Coleoptera) are covered primarily by a hard exoskeleton or cuticle. For example, the beetle elytron is a cuticle-rich highly modified forewing structure that shields the underlying hindwing and dorsal body surface from a variety of harmful environmental factors by acting as an armor plate. The elytron comes in a variety of colors and shapes depending on the coleopteran species. As in many other insect species, the cuticular tanning pathway begins with tyrosine and is responsible for production of a variety of melanin-like and other types of pigments. Tanning metabolism involves quinones and quinone methides, which also act as protein cross-linking agents for cuticle sclerotization. Electron microscopic analyses of rigid cuticles of the red flour beetle, Tribolium castaneum, have revealed not only numerous horizontal chitin-protein laminae but also vertically oriented columnar structures called pore canal fibers. This structural architecture together with tyrosine metabolism for cuticle tanning is likely to contribute to the rigidity and coloration of the beetle exoskeleton.

  13. Systematics of Fusaria associated with Ambrosia beetles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Here, I summarize research efforts directed at char