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Sample records for palmi karny thysanoptera

  1. Detection and Localization of Wolbachia in Thrips palmi Karny (Thysanoptera: Thripidae).

    PubMed

    Saurav, Gunjan Kumar; Daimei, Guisuibou; Rana, Vipin Singh; Popli, Sonam; Rajagopal, Raman

    2016-06-01

    Thrips palmi Karny is a globally distributed polyphagous agricultural pest. It causes huge economic loss by its biological behaviors like feeding, reproduction and transmission of tospoviruses. Since T. palmi shows close morphological similarities with other thrips species, we employed mitochondrial cytochrome oxidase 1 (mtCO1) gene as a molecular marker. BLAST analysis of this sequence helped us to identify the collected specimen as T. palmi. We observed the female to male ratio of about 3:1 from collected samples and suspected the presence of Wolbachia. The presence of Wolbachia was detected by PCR using genus specific primers of 16S rRNA gene. Further confirmation of Wolbachia strain was achieved by conducting PCR amplification of three ubiquitous genes ftsZ, gatB and groEL. A phylogenetic tree was constructed with concatenated sequences of ftsZ and gatB gene to assign supergroup to Wolbachia. Finally, we localized Wolbachia in abdominal region of the insect using fluorescent in situ hybridization with the help of confocal microscope. Our result confirmed the presence of Wolbachia supergroup B strain for the first time in T. palmi. PMID:27570308

  2. The First Report of miRNAs from a Thysanopteran Insect, Thrips palmi Karny Using High-Throughput Sequencing

    PubMed Central

    Asokan, R.; Hande, H. Ranjitha; Krishna Kumar, N. K.

    2016-01-01

    Thrips palmi Karny (Thysanoptera: Thripidae) is the sole vector of Watermelon bud necrosis tospovirus, where the crop loss has been estimated to be around USD 50 million annually. Chemical insecticides are of limited use in the management of T. palmi due to the thigmokinetic behaviour and development of high levels of resistance to insecticides. There is an urgent need to find out an effective futuristic management strategy, where the small RNAs especially microRNAs hold great promise as a key player in the growth and development. miRNAs are a class of short non-coding RNAs involved in regulation of gene expression either by mRNA cleavage or by translational repression. We identified and characterized a total of 77 miRNAs from T. palmi using high-throughput deep sequencing. Functional classifications of the targets for these miRNAs revealed that majority of them are involved in the regulation of transcription and translation, nucleotide binding and signal transduction. We have also validated few of these miRNAs employing stem-loop RT-PCR, qRT-PCR and Northern blot. The present study not only provides an in-depth understanding of the biological and physiological roles of miRNAs in governing gene expression but may also lead as an invaluable tool for the management of thysanopteran insects in the future. PMID:27685664

  3. Effects of temperature on the development and population growth of the melon thrips, Thrips palmi, on eggplant, Solanum melongena.

    PubMed

    Yadav, Ramchandra; Chang, Niann-Tai

    2014-05-30

    The effects of temperature on the melon thrips, Thrips palmi Karny (Thysanoptera: Thripidae), preimaginal development, survival, fecundity, longevity of females and males, and population growth were investigated at 16, 19, 22, 25, 28, and 31° C, 70-80% RH, and a photoperiod of 12:12 L:D. The results indicated that the duration of egg, larval, and pupal stages was significantly influenced by increased temperature. The egg-to-adult developmental period of T. palmi declined from 35.7 to 9.6 days as the temperature increased from 16 to 31° C. The developmental threshold temperature estimated for egg-to-adult was 11.25° C, with a thermal constant of 196.1 degree-days. The developmental threshold temperature was 13.91, 11.82, 9.36, and 10.45° C for adult preoviposition period, total preoviposition period, female longevity, and male longevity, respectively. The thermal constants for completing the adult preoviposition period, total preoviposition period, female longevity, and male longevity were 29.3, 227.3, 454.6, and 344.8 degree-days, respectively. Female longevity was found to be shortest at 31° C (18.7 days) and longest at 16° C (56.7 days), and male longevity was shortest at 31° C (15.5 days) and longest at 16° C (50.7 days). Fecundity was highest at 25° C (64.2 eggs/female) and lowest at 16° C (23.4 eggs/female). The population trend index of T. palmi was highest at 25° C (31.3) and lowest at 16° C (7.6). The optimal developmental temperature for T. palmi in eggplant, Solanum melongena L. (Solanales: Solanaceae), was determined to be 25° C.

  4. Detection of the Quarantine Species Thrips palmi by Loop-Mediated Isothermal Amplification

    PubMed Central

    Przybylska, Arnika; Fiedler, Żaneta; Kucharczyk, Halina; Obrępalska-Stęplowska, Aleksandra

    2015-01-01

    Thrips palmi (from the order Thysanoptera) is a serious insect pest of various crops, including vegetables, fruits and ornamental plants, causing significant economic losses. Its presence constitutes a double threat; not only does T. palmi feed on the plants, it is also a vector for several plant viruses. T. palmi originated in Asia, but has spread to North and Central America, Africa, Oceania and the Caribbean in recent decades. This species has been sporadically noted in Europe and is under quarantine regulation in the European Union. For non-specialists its larval stages are indistinguishable morphologically from another widespread and serious insect pest Frankliniella occidentalis (a non-quarantine species in the European Union) as well as other frequently occurring thrips. In this study, we have developed a loop-mediated isothermal amplification protocol to amplify rDNA regions of T. palmi. The results were consistent whether isolated DNA or crushed insects were used as template, indicating that the DNA isolation step could be omitted. The described method is species-specific and sensitive and provides a rapid diagnostic tool to detect T. palmi in the field. PMID:25793743

  5. Specificity of accumulation and transmission of tomato spotted wilt virus (TSWV) in two genera, Frankliniella and Thrips (Thysanoptera: Thripidae).

    PubMed

    Inoue, T; Sakurai, T; Murai, T; Maeda, T

    2004-12-01

    The accumulation and transmission of tomato spotted wilt virus (TSWV) was examined in second instar larvae and adults of two thrips genera, Frankliniella and Thrips. The species tested were F. occidentalis (Pergande), F. intonsa (Trybom), T. tabaciLindeman, T. setosus Moulton, T. palmi Karny and T. hawaiiensis (Morgan). In a standard petunia leaf disc assay, the efficiencies of TSWV transmission by two species of Frankliniella were higher than those of any Thrips species in the adult stage. A triple antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) showed that large amounts of the TSWV-nucleocapsid (N) protein were present in the ELISA-positive larvae of each species, with the exception of T. palmi. The ELISA titre of and the proportion of virus-infected individuals of the two Frankliniella species increased or did not significantly change from the larval to the adult stages, whereas those of the four Thrips species decreased significantly. These results show that the specificity of virus transmission by adult thrips is probably affected by the amount of viral N protein accumulation in the adults and that the accumulation pattern from the larval to the adult stages is in between the two genera tested in the present study.

  6. Thysanoptera of bulgaria.

    PubMed

    Karadjova, Olia; Krumov, Vladimir

    2015-01-01

    The present checklist includes data on the species composition, geographic distribution and feeding preferences of thrips species in Bulgaria. In total, 155 species in 48 genera are listed. Of these, 125 species belong to suborder Terebrantia and include 103 species of 33 genera in family Thripidae, 14 species of two genera in Aeolothripidae, seven species of two genera in Melanthripidae and one species in Fauriellidae. In suborder Tubulifera, 30 species of 10 genera in the single family Phlaeothripidae are listed. Of the 155 Bulgarian thrips species, 87.7% are phytophagous, 4.5% are obligate predators, 5.8% are mycophagous and 1.9% are with unknown feeding preferences. Fourteen pest species are listed for Bulgaria, of which Frankliniellaoccidentalis, Thripstabaci and Haplothripstritici are of economic importance. The list provides detailed information on the horizontal and vertical distribution of Thysanoptera in 5 regions and 45 subregions of Bulgaria. The present paper also includes an evaluation of the biodiversity of Thysanoptera and the extent to which each region of the country has been studied. PMID:26019678

  7. Thysanoptera of Bulgaria

    PubMed Central

    Karadjova, Olia; Krumov, Vladimir

    2015-01-01

    Abstract The present checklist includes data on the species composition, geographic distribution and feeding preferences of thrips species in Bulgaria. In total, 155 species in 48 genera are listed. Of these, 125 species belong to suborder Terebrantia and include 103 species of 33 genera in family Thripidae, 14 species of two genera in Aeolothripidae, seven species of two genera in Melanthripidae and one species in Fauriellidae. In suborder Tubulifera, 30 species of 10 genera in the single family Phlaeothripidae are listed. Of the 155 Bulgarian thrips species, 87.7% are phytophagous, 4.5% are obligate predators, 5.8% are mycophagous and 1.9% are with unknown feeding preferences. Fourteen pest species are listed for Bulgaria, of which Frankliniella occidentalis, Thrips tabaci and Haplothrips tritici are of economic importance. The list provides detailed information on the horizontal and vertical distribution of Thysanoptera in 5 regions and 45 subregions of Bulgaria. The present paper also includes an evaluation of the biodiversity of Thysanoptera and the extent to which each region of the country has been studied. PMID:26019678

  8. Identification of the Aggregation Pheromone of the Melon Thrips, Thrips palmi

    PubMed Central

    Akella, Sudhakar V. S.; Kirk, William D. J.; Lu, Yao-bin; Murai, Tamotsu; Walters, Keith F. A.; Hamilton, James G. C.

    2014-01-01

    The objective of this study was to identify the aggregation pheromone of the melon thrips Thrips palmi, a major pest of vegetable and ornamental plants around the world. The species causes damage both through feeding activities and as a vector of tospoviruses, and is a threat to world trade and European horticulture. Improved methods of detecting and controlling this species are needed and the identification of an aggregation pheromone will contribute to this requirement. Bioassays with a Y-tube olfactometer showed that virgin female T. palmi were attracted to the odour of live males, but not to that of live females, and that mixed-age adults of both sexes were attracted to the odour of live males, indicating the presence of a male-produced aggregation pheromone. Examination of the headspace volatiles of adult male T. palmi revealed only one compound that was not found in adult females. It was identified by comparison of its mass spectrum and chromatographic details with those of similar compounds. This compound had a structure like that of the previously identified male-produced aggregation pheromone of the western flower thrips Frankliniella occidentalis. The compound was synthesised and tested in eggplant crops infested with T. palmi in Japan. Significantly greater numbers of both males and females were attracted to traps baited with the putative aggregation pheromone compared to unbaited traps. The aggregation pheromone of T. palmi is thus identified as (R)-lavandulyl 3-methyl-3-butenoate by spectroscopic, chromatographic and behavioural analysis. PMID:25101871

  9. Meniscus ascent by thrips (Thysanoptera).

    PubMed

    Ortega-Jiménez, Victor Manuel; Arriaga-Ramirez, Sarahi; Dudley, Robert

    2016-09-01

    Meniscus climbing using a fixed body posture has been well documented for various aquatic and neustonic insects, but is not known from small flying insects that inadvertently become trapped on water surfaces. Here, we show that thrips (order Thysanoptera) can ascend a meniscus by arching their non-wetting bodies to translate head-first and upward along a water surface; if initially oriented backwards, they can turn by 180° to ascend head-first, and climb upward on a surrounding boundary. Using variable-concentration sucrose solutions, we show that translational and climbing speeds during meniscus ascent vary inversely with fluid viscosity. Becoming trapped in water is a frequent event for flying insects, and given that most of them are very small, dedicated behaviours to escape water may be commonplace among pterygotes. PMID:27624795

  10. Effect of Watermelon Silver Mottle Virus on the Life History and Feeding Preference of Thrips palmi

    PubMed Central

    Chen, Wei-Te; Tseng, Chien-Hao; Tsai, Chi-Wei

    2014-01-01

    Thrips-borne tospoviruses cause numerous plant diseases that produce severe economic losses worldwide. In the disease system, thrips not only damage plants through feeding but also transmit causative agents of epidemics. In addition, thrips are infected with tospoviruses in the course of virus transmission. Most studies on the effect of tospoviruses on vector thrips have focused on the Tomato spotted wilt virus–Frankliniella occidentalis system. Thus, we focused on another thrips-borne tospovirus, Watermelon silver mottle virus (WSMoV), to examine the effect of virus infection on its vector, Thrips palmi. In this study, the direct and indirect effects of WSMoV on the life history traits and feeding preference of T. palmi were examined. The survival rate and developmental time of the WSMoV-infected larval thrips did not differ significantly from those of the virus-free thrips. Comparing the developmental time of larval thrips fed on the healthy plants, thrips-damaged plants, and thrips-inoculated plants (the WSMoV-infected plants caused by thrips feeding), feeding on the thrips-damaged plants reduced the developmental time, and the WSMoV infection in host plants partially canceled the effect of thrips damage on the developmental time. In addition, no significant variations between the virus-free and WSMoV-infected adult thrips regarding longevity and fecundity were observed. These results implied that WSMoV did not directly affect the life history traits of T. palmi, but the WSMoV infection indirectly affected the development of T. palmi through the virus-infected plants. Furthermore, feeding preference tests indicated that T. palmi preferred feeding on either the thrips-damaged plants or the thrips-inoculated plants to the healthy plants. The effect of tospoviruses on the life history and feeding preference of vector thrips might vary among host plants, virus species, vector species, and environmental factors. PMID:25010157

  11. Thysanoptera-Terebrantia of the Hawaiian Islands: an identification manual

    PubMed Central

    Mound, Laurence; Nakahara, Sueo; Tsuda, Dick M.

    2016-01-01

    Abstract An illustrated identification system is presented to 99 species and 49 genera in three families recorded from the Hawaiian Islands in the Thysanoptera suborder Terebrantia. Only seven (possibly eight) of these species are considered endemic, the remainder being adventive to these islands. The only previous study of Hawaiian Thysanoptera, by Zimmerman in 1948, included 47 Terebrantia species in 21 genera. PMID:26843832

  12. The fine structure of the rectal pads of Zorotypus caudelli Karny (Zoraptera, Insecta).

    PubMed

    Dallai, R; Mercati, D; Mashimo, Y; Machida, R; Beutel, R G

    2016-07-01

    The rectal pads of a species of the controversial polyneopteran order Zoraptera were examined using histological sections and TEM micrographs. Six pads are present along the thin rectal epithelium. Each pad consists of a few large principal cells surrounded by flattened junctional cells, which extend also beneath the principal cells. The cells are lined by a thin apical cuticle. No basal cells and no cavity have been observed beneath the pad. Principal cells have a regular layer of apical microvilli and are joined by intercellular septate junctions, which are interrupted by short dilatations of the intercellular space. At these levels the two adjacent plasma membranes are joined by short zonulae adhaerentes. In the cytoplasm, a rich system of strict associations between lateral plasma membranes and mitochondria forms scalariform junctions. Rectal pads share ultrastructural features with similar excretory organs of several neopteran groups, in particular with Blattodea (roaches and termites) and Thysanoptera, and are involved in fluid reabsorption and ion regulation. PMID:27368527

  13. A Trichodorus (Triplonchida: Trichodoridae) nematode from thrips (Thysanoptera: Panchaetothripinae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A thrips insect Caliothrips sp. (Thysanoptera: Panchaetothripinae) from persimmon fruit (Ebenaceae: Diospyros sp.) from an unknown origin, possibly Asia, was intercepted in a passenger bag in November 2012 at the Peace Arch Border Crossing from Surrey, British Columbia to Blaine, Washington by an AP...

  14. Gynaikothrips uzeli (Thysanoptera: Phlaeothripidae), new record from Tartous, Syria.

    PubMed

    Ali, Ali Yaseen

    2014-01-01

    The weeping fig thrips Gynaikothrips uzeli Zimmermann (Thysanoptera: Phlaeothripidae) is newly recorded for the first time in the leaf galls of the weeping fig tree Ficus benjamina L. (Rosales: Moraceae) in the coastal area of Tartous, Syria. The thrips caused purplish red spots on the leaf surface of the host plant and the leaves curl. G. uzeili appears to be successfully adapted to this area.

  15. Ecology and behavior of Pezothrips kellyanus (Thysanoptera: Thripidae) on citrus.

    PubMed

    Vassiliou, V A

    2010-02-01

    The most common thrips species found in Cyprus citrus orchards between 2003 and 2008 were Pezothrips kellyanus (Bagnall) (Thysanoptera: Thripidae), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and Thrips tabaci (Lindeman) (Thysanoptera: Thripidae). Only Pezothrips kellyanus, Kelly's citrus thrips (KCT) causes feeding damage on citrus fruits in Cyprus. KCT adults prefer to concentrate mostly in the northern and eastern sides of both lemon and grapefruit canopies. The attractiveness of white, sky blue, marine blue, and yellow color to KCT was evaluated. White was found to be the most attractive color to adults of KCT, F. occidentalis, and T. tabaci. A range of incidental and breeding host plants grown within and outside citrus orchards in Cyprus were identified. KCT adults were found on flowers of all citrus varieties, and various other flowering plants including Malva nicaeensis, Malva silvestris, Sinapis alba, Oxalis pes-caprae, Calendula arvensis, Urospermum picroides, Jasminum officinale, Gardenia jasminoides, Jasminum sambac, Prunus dulcis, Mangifera indica, Persea americana, and Eriobotrya japonica. KCT larvae were found only on lemon, grapefruit, Jasmine spp., and Gardenia flowers. PMID:20214367

  16. Analysis of the thrips fauna (Thysanoptera) on flowers of herbs.

    PubMed

    Pobozniak, Maria

    2007-01-01

    Studies of Thysanoptera were realized at the Agricultural Experimental Station in Mydlniki near Cracow over the years 2003-2005. This research work covers the observations of the species composition of thrips and the periods of the occurrence of the particulars species of thrips and their numerousness. The thrips were collected from flowers of Valeriana officinalis L., Hypericum perforatum L. and Levisticum officinale Koch. Following thrips species dominated samples collected directly from plants: Frankliniella intonsa (Trybom), Thrips fuscipennis Haliday, Thrips tabaci Lindeman and Thrips major Uzel. The greatest number of thrips was noticed during flowering period on Valeriana officinalis L., and Hypericum perforatum L.

  17. Thrips (Insecta, Thysanoptera) of Iran: a revised and updated checklist

    PubMed Central

    Minaei, Kambiz

    2013-01-01

    Abstract In Iran, as a result of recent changes in nomenclature 201 species and one species group of the insect Order Thysanoptera, are here listed in 70 genera and five families. In considering species listed previously from this country, the presence of 7 species is considered not confirmed, and 12 species are excluded from the Iranian list. Problems in the study of Iranian Thysanoptera are discussed briefly. PMID:24146555

  18. Distribution and ecology of Frankliniella occidentalis (Thysanoptera: Thripidae) bacterial symbionts.

    PubMed

    Chanbusarakum, Lisa J; Ullman, Diane E

    2009-08-01

    Bacterial populations in Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) collected in diverse California environments consisted of two bacterial symbionts: BFo-1 and BFo-2 (B = bacteria, Fo = Frankliniella occidentalis, numbers reflect different types). Dual infections of BFo-1 and BFo-2 were found in 50% of the thrips, 18% had neither bacterium, and 24 and 8% were infected solely with BFo-1 and BFo-2, respectively. No other bacteria consistently infected F. occidentalis. Dual infections occurred more often in male thrips and in thrips of both sexes from southern mountain and valley sites. As average collection year or month minimum temperature decreased, infections of BFo-1, alone or in dual infections, increased significantly. As yearly precipitation increased, infection with BFo-1 alone also increased. F. occidentalis color morphology did not affect bacterial infection. BFo-1 created weak biofilms at 25 and 32 degrees C; BFo-2 made strong biofilms at 25 degrees C and no biofilms at 32 degrees C. When the bacteria were grown in culture together, weak biofilms formed at both temperatures studied, although there was no way to determine what each bacterium contributed to the biofilm. BFo-1 and BFo-2 grew at similar rates at 25 and 30 degrees C. Our data show BFo-1 and BFo-2 occur in natural populations of F. occidentalis and support the hypothesis BFo have a symbiotic relationship with F. occidentalis. Regional differences in bacterial prevalence suggest bacterial infection is associated with environmental conditions, and altitude, temperature, and precipitation may be important factors. PMID:19689885

  19. A Trichodorus (Triplonchida: Trichodoridae) Nematode from Thrips (Thysanoptera: Panchaetothripinae)

    PubMed Central

    Carta, L. K.; Skantar, A. M.

    2014-01-01

    A thrips insect Caliothrips sp. (Thysanoptera: Panchaetothripinae) from persimmon fruit (Ebenaceae: Diospyros sp.) from an unknown origin, possibly Asia, was intercepted in a passenger bag in November 2012 at the Peace Arch Border Crossing from Canada to Blaine, WA, by a USDA-APHIS-PPQ port inspector. Nematodes were attached to the abdomen of the female insect and sent to us in saline. Seven nematodes (five females, two males) were measured and these and others were processed for permanent slides. An adult female and a female juvenile were prepared for PCR. Morphologically these nematodes belonged to the Trichodorus sparsus group, and the 28S rDNA D2-D3 sequence showed greatest similarity to Trichodorus paragiennensis (94%) and T. giennensis (93%), with greatest morphological similarity to the latter species. Among other morphological differences, the innermost uterus width is wider than in related species. Trichodorus spp. are normally found in soil, so this is the first population seen in the atypical habitat of an insect. Morphological and molecular characteristics of Trichodorus sp. are presented, but a putative new species name is not currently advisable because of relatively poor condition of specimens. Ecological associations are also discussed. PMID:25276005

  20. An overview of chilli thrips. Scirtothrips dorsalis (Thysanoptera: Thripidae) biology, distribution and management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In the insect order Thysanoptera, the genus Scirtothrips Shull contains more than 100 thrips species, among which 10 species have been reported as serious pests of agricultural crops. Within this genus, Scirtothrips dorsalis Hood is an emerging pest of various economically important host crops in th...

  1. An illustrated key to the genera of Thripinae (Thysanoptera, Thripidae) from Iran

    PubMed Central

    Mirab-balou, Majid; Minaei, Kambiz; Chen, Xue-Xin

    2013-01-01

    Abstract An illustrated key is provided for the identification of 35 genera of Thripinae (Thysanoptera: Thripidae) from Iran with comments for each genus. Chirothrips maximi Ananthakrishnan and Limothrips cerealium Haliday are recorded from Iran for the first time. A checklist is provided of Thripinae recorded from this country. PMID:23950669

  2. Thysanoptera intercepted in the Netherlands on plant products from Ethiopia, with description of two new species of the genus Thrips.

    PubMed

    Vierbergen, Gijsbertus

    2014-01-01

    An overview is given of 18 Thysanoptera species found on Ethiopian cut flowers, cuttings and vegetables during import inspection in the Netherlands. Consignments consisted mostly of cut flowers, in total belonging to twelve plant genera. Details on geographical distribution and host plants of the thrips encountered are given, and two are newly described: T. cacuminis sp. n. and T. dezeeuwi sp. n. The results do not give any serious indication of increased invasiveness by Ethiopian Thysanoptera

  3. Genomic analyses of sodium channel α-subunit genes from strains of melon thrips, Thrips palmi, with different sensitivities to cypermethrin.

    PubMed

    Bao, Wen Xue; Kataoka, Yoko; Kohara, Yoko; Sonoda, Shoji

    2014-01-01

    We examined the genomic organization of the sodium channel α-subunit gene in two strains of melon thrips, Thrips palmi, having differing sensitivity to cypermethrin. The nucleotide sequences of the strains included 18 or 16 putative exons which covered the entire coding region of the gene producing 2039 amino acid residues. Deduced amino acid sequences of both strains showed 80% homology with those of Periplaneta americana and Cimex lectularius. Comparison of deduced amino acid sequences of both strains showed no consistent amino acid difference. In addition to the previously reported resistant amino acid (Ile) at the T929I site, both strains encoded another resistant amino acids at two positions which are involved in pyrethroid resistance in other arthropods. These amino acids might also involve in the basal levels of resistance to pyrethroids of both strains.

  4. ESTIMATING BACTERIAL DIVERSITY IN SCIRTOTHRIPS DORSALIS (THYSANOPTERA: THRIPIDAE) VIA NEXT GENERATION SEQUENCING.

    PubMed

    Dickey, Aaron M; Trease, Andrew J; Jara-Cavieres, Antonella; Kumar, Vivek; Christenson, Matthew K; Potluri, Lakshmi-Prasad; Morgan, J Kent; Shatters, Robert G; Mckenzie, Cindy L; Davis, Paul H; Osborne, Lance S

    2014-06-01

    The last 2 decades have produced a better understanding of insect-microbial associations and yielded some important opportunities for insect control. However, most of our knowledge comes from model systems. Thrips (Thysanoptera: Thripidae) have been understudied despite their global importance as invasive species, plant pests and disease vectors. Using a culture and primer independent next-generation sequencing and metagenomics pipeline, we surveyed the bacteria of the globally important pest, Scirtothrips dorsalis Hood. The most abundant bacterial phyla identified were Actinobacteria and Proteobacteria and the most abundant genera were Propionibacterium, Stenotrophomonas, and Pseudomonas. A total of 189 genera of bacteria were identified. The absence of any vertically transferred symbiont taxa commonly found in insects is consistent with other studies suggesting that thrips primarilly acquire resident microbes from their environment. This does not preclude a possible beneficial/intimate association between S. dorsalis and the dominant taxa identified and future work should determine the nature of these associations. PMID:25382863

  5. Night of the living thrips: an unusual outbreak of Thysanoptera dermatitis.

    PubMed

    Carness, Jeffrey M; Winchester, Jonathan C; Oras, Michael J; Arora, Navin S

    2016-03-01

    Identifying the etiology of a cutaneous eruption in the setting of an acute cluster outbreak is of utmost importance due to the inherent potential public health impact. The differential diagnosis ranges from innocuous arthropod bites to more concerning causes such as infection, medication reaction, and environmental exposure. We report the simultaneous presentation of 15 US Marines who presented with numerous discrete papular skin eruptions. Subsequent thorough patient evaluation and history, literature review, immunization status reconciliation, entomological assessment, site survey, and skin biopsy were performed. This case series is one of the largest reported to date of a cluster outbreak of a papular dermatitis secondary to bites from thrips (ie, insects of the order Thysanoptera). PMID:27023090

  6. Night of the living thrips: an unusual outbreak of Thysanoptera dermatitis.

    PubMed

    Carness, Jeffrey M; Winchester, Jonathan C; Oras, Michael J; Arora, Navin S

    2016-03-01

    Identifying the etiology of a cutaneous eruption in the setting of an acute cluster outbreak is of utmost importance due to the inherent potential public health impact. The differential diagnosis ranges from innocuous arthropod bites to more concerning causes such as infection, medication reaction, and environmental exposure. We report the simultaneous presentation of 15 US Marines who presented with numerous discrete papular skin eruptions. Subsequent thorough patient evaluation and history, literature review, immunization status reconciliation, entomological assessment, site survey, and skin biopsy were performed. This case series is one of the largest reported to date of a cluster outbreak of a papular dermatitis secondary to bites from thrips (ie, insects of the order Thysanoptera).

  7. Selection of colour of sticky trap for monitoring adult bean thrips, Caliothrips fasciatus (Thysanoptera: Thripidae).

    PubMed

    Harman, J Alex; Mao, Chang Xuan; Morse, Joseph G

    2007-02-01

    Adult bean thrips, Caliothrips fasciatus (Pergande), overwintering inside the navel of navel oranges shipped from California to Australia, are an actionable pest for the importing country, i.e. infested lots are fumigated with methyl bromide. Strict quarantine regulations regarding C. fasciatus prompted studies on the best colour sticky trap that might be used to monitor for bean thrips populations in the vicinity of California citrus groves prior to harvesting fruit for export. Preliminary experiments identified the most attractive trap of each of four colours (blue, green, white, yellow) commonly used to sample adult Thysanoptera. Three trials of a field study were conducted, comparing C. fasciatus capture on the best card of each colour using asparagus ferns naturally infested with high levels of this pest. Based on significantly higher catch on green sticky cards, this colour trap is recommended for potential use in California's bean thrips mitigation plan designed to reduce thrips levels on citrus exported to Australia.

  8. Identification of the terebrantian thrips (Insecta, Thysanoptera) associated with cultivated plants in Java, Indonesia

    PubMed Central

    Sartiami, Dewi; Mound, Laurence A.

    2013-01-01

    Abstract An illustrated identification key is provided to 49 species of Thysanoptera, Terebrantia that have been found in association with cultivated plants in Java. This is the first published identification system to this group of insects from Indonesia, and includes 15 species not previously recorded from Indonesia, and a further three species not previously recorded from Java. A table is provided indicating the plants from which thrips were taken. PMID:23794915

  9. Identification of the terebrantian thrips (Insecta, Thysanoptera) associated with cultivated plants in Java, Indonesia.

    PubMed

    Sartiami, Dewi; Mound, Laurence A

    2013-01-01

    An illustrated identification key is provided to 49 species of Thysanoptera, Terebrantia that have been found in association with cultivated plants in Java. This is the first published identification system to this group of insects from Indonesia, and includes 15 species not previously recorded from Indonesia, and a further three species not previously recorded from Java. A table is provided indicating the plants from which thrips were taken.

  10. DNA Barcode Analysis of Thrips (Thysanoptera) Diversity in Pakistan Reveals Cryptic Species Complexes

    PubMed Central

    Iftikhar, Romana; Ashfaq, Muhammad; Rasool, Akhtar; Hebert, Paul D. N.

    2016-01-01

    Although thrips are globally important crop pests and vectors of viral disease, species identifications are difficult because of their small size and inconspicuous morphological differences. Sequence variation in the mitochondrial COI-5ʹ (DNA barcode) region has proven effective for the identification of species in many groups of insect pests. We analyzed barcode sequence variation among 471 thrips from various plant hosts in north-central Pakistan. The Barcode Index Number (BIN) system assigned these sequences to 55 BINs, while the Automatic Barcode Gap Discovery detected 56 partitions, a count that coincided with the number of monophyletic lineages recognized by Neighbor-Joining analysis and Bayesian inference. Congeneric species showed an average of 19% sequence divergence (range = 5.6% - 27%) at COI, while intraspecific distances averaged 0.6% (range = 0.0% - 7.6%). BIN analysis suggested that all intraspecific divergence >3.0% actually involved a species complex. In fact, sequences for three major pest species (Haplothrips reuteri, Thrips palmi, Thrips tabaci), and one predatory thrips (Aeolothrips intermedius) showed deep intraspecific divergences, providing evidence that each is a cryptic species complex. The study compiles the first barcode reference library for the thrips of Pakistan, and examines global haplotype diversity in four important pest thrips. PMID:26741134

  11. Onion thrips (Thysanoptera: Thripidae): a global pest of increasing concern in onion.

    PubMed

    Diaz-Montano, John; Fuchs, Marc; Nault, Brian A; Fail, József; Shelton, Anthony M

    2011-02-01

    During the past two decades, onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), has become a global pest of increasing concern in commercial onion (Allium cepa L.), because of its development of resistance to insecticides, ability to transmit plant pathogens, and frequency of producing more generations at high temperatures. T. tabaci feeds directly on leaves, causing blotches and premature senescence as well as distorted and undersized bulbs. T. tabaci can cause yield loss > 50% but can be even more problematic when it transmits Iris yellow spot virus (family Bunyaviridae, genus Tospovirus, IYSV). IYSV was identified in 1981 in Brazil and has spread to many important onion-producing regions of the world, including several U.S. states. IYSV symptoms include straw-colored, dry, tan, spindle- or diamond-shaped lesions on the leaves and scapes of onion plants and can cause yield loss up to 100%. Here, we review the biology and ecology of T. tabaci and discuss current management strategies based on chemical, biological, and cultural control as well as host resistance. Future directions for research in integrated pest management are examined and discussed. PMID:21404832

  12. Within-plant distribution of onion thrips (Thysanoptera: Thripidae) in onions.

    PubMed

    Mo, Jianhua; Munro, Scott; Boulton, Alan; Stevens, Mark

    2008-08-01

    Two aspects of the within-plant distribution of Thrips tabaci Lindeman (Thysanoptera: Thripidae) on onion, Allium cepa L., plants were investigated: 1) diurnal variations in the distribution of adults and larvae between basal and upper sections of onion leaves, and 2) between-leaf and within-leaf distribution of the eggs. The diurnal investigations showed that higher proportions of larvae than of adults congregated at the basal sections of plants, particularly when plants were young and thrips density was low. As plants matured and thrips density increased, the larvae became more dispersed. Regardless of plant size, there were always more adults in the upper than basal plant sections. There were no clear time-windows during the 24-h diurnal cycle when more thrips were in the upper plant parts. T. tabaci eggs were laid everywhere in the plant. Leaves of intermediate ages had more eggs than older or younger leaves. Within leaves, the white leaf sheath received the least eggs and leaf tips received slightly more eggs than leaf sheaths. The highest egg density was found between the green leaf base and the leaf tips. Regardless of plant size, more than half of all eggs were laid above the basal sections. The percentage increased to >95% in mature plants. Except when plants were small the outer leaves were preferred over inner leaves and upper leaf sections preferred over lower leaf sections as egg-laying sites by adults. Implications of the results in the management of T. tabaci are discussed.

  13. Holopothrips molzi sp.n. (Thysanoptera, Phlaeothripidae): natural history and interactions in Myrtaceae galls.

    PubMed

    Lindner, Mariana Flores; Mendonça, Milton De Souza Jr; Cavalleri, Adriano

    2016-01-01

    Holopothrips molzi sp. n. (Thysanoptera: Phlaeothripidae) is described from southern Brazil inducing leaf galls on Myrcia guianensis (Myrtaceae). Field observations revealed that the numbers of this thrips were highly variable within galls, and two other insect species were recorded living in these galls: Myrciathrips variabilis Cavalleri et al. (Phlaeothripidae) and an eulophid wasp (Hymenoptera). We investigated here if morphological traits of leaf and gall and abundance of the invader thrips were correlated with the gall inducer's abundance. In order to determine the feeding habit and behaviour of M. variabilis and its interactions with the gall inducer we performed observations ad libitum and attack simulation tests on both thrips species to observe their response to possible invaders. Our results showed that leaf size is not related to H. molzi abundance, and gall size is relevant only when total numbers of both thrips species are considered. Myrciathrips variabilis was observed feeding on gall tissues, and no direct antagonistic interactions between the two thrips were recorded. The results of the behavioural tests simulating attacks were remarkably different in the two thrips species, indicating different strategies when threatened or disturbed. The interaction between the two thrips species is probably a case of inquilinism. PMID:27395120

  14. Natural Enemies of the Frankliniella Complex Species (Thysanoptera: Thripidae) in Ataulfo Mango Agroecosystems.

    PubMed

    Rocha, Franklin H; Infante, Francisco; Castillo, Alfredo; Ibarra-Nuñez, Guillermo; Goldarazena, Arturo; Funderburk, Joe E

    2015-01-01

    A field survey was conducted in Ataulfo mango (Mangifera indica L.) orchards in Chiapas, Mexico, with the objective of determining the natural enemies of the Frankliniella complex species (Thysanoptera: Thripidae). Seven species of this genus feed and reproduce in large numbers during the mango flowering. Two representative orchards were selected: the orchard "Tres A" characterized by an intensive use of agrochemicals directed against thrips, and the orchard "La Escondida" that did not spray insecticides. During mango flowering, five inflorescences were randomly collected every 5 d in both orchards, for a total of 18 sampling dates. Results revealed the presence of 18 species of arthropods that were found predating on Frankliniella. There were 11 species in the families Aeolothripidae, Phlaeothripidae, Formicidae, Anthocoridae and Chrysopidae; and seven species of spiders in the families Araneidae, Tetragnathidae, and Uloboridae. Over 88% of predators were anthocorids, including, Paratriphleps sp. (Champion), Orius insidiosus (Say), Orius tristicolor (White), and O. perpunctatus (Reuter). The orchard that did not spray insecticides had a significantly higher number of predators suggesting a negative effect of the insecticides on the abundance of these organisms.

  15. Natural Enemies of the Frankliniella Complex Species (Thysanoptera: Thripidae) in Ataulfo Mango Agroecosystems

    PubMed Central

    Rocha, Franklin H.; Infante, Francisco; Castillo, Alfredo; Ibarra-Nuñez, Guillermo; Goldarazena, Arturo; Funderburk, Joe E.

    2015-01-01

    A field survey was conducted in Ataulfo mango (Mangifera indica L.) orchards in Chiapas, Mexico, with the objective of determining the natural enemies of the Frankliniella complex species (Thysanoptera: Thripidae). Seven species of this genus feed and reproduce in large numbers during the mango flowering. Two representative orchards were selected: the orchard “Tres A” characterized by an intensive use of agrochemicals directed against thrips, and the orchard “La Escondida” that did not spray insecticides. During mango flowering, five inflorescences were randomly collected every 5 d in both orchards, for a total of 18 sampling dates. Results revealed the presence of 18 species of arthropods that were found predating on Frankliniella. There were 11 species in the families Aeolothripidae, Phlaeothripidae, Formicidae, Anthocoridae and Chrysopidae; and seven species of spiders in the families Araneidae, Tetragnathidae, and Uloboridae. Over 88% of predators were anthocorids, including, Paratriphleps sp. (Champion), Orius insidiosus (Say), Orius tristicolor (White), and O. perpunctatus (Reuter). The orchard that did not spray insecticides had a significantly higher number of predators suggesting a negative effect of the insecticides on the abundance of these organisms. PMID:26246440

  16. Within-plant distribution of onion thrips (Thysanoptera: Thripidae) in onions.

    PubMed

    Mo, Jianhua; Munro, Scott; Boulton, Alan; Stevens, Mark

    2008-08-01

    Two aspects of the within-plant distribution of Thrips tabaci Lindeman (Thysanoptera: Thripidae) on onion, Allium cepa L., plants were investigated: 1) diurnal variations in the distribution of adults and larvae between basal and upper sections of onion leaves, and 2) between-leaf and within-leaf distribution of the eggs. The diurnal investigations showed that higher proportions of larvae than of adults congregated at the basal sections of plants, particularly when plants were young and thrips density was low. As plants matured and thrips density increased, the larvae became more dispersed. Regardless of plant size, there were always more adults in the upper than basal plant sections. There were no clear time-windows during the 24-h diurnal cycle when more thrips were in the upper plant parts. T. tabaci eggs were laid everywhere in the plant. Leaves of intermediate ages had more eggs than older or younger leaves. Within leaves, the white leaf sheath received the least eggs and leaf tips received slightly more eggs than leaf sheaths. The highest egg density was found between the green leaf base and the leaf tips. Regardless of plant size, more than half of all eggs were laid above the basal sections. The percentage increased to >95% in mature plants. Except when plants were small the outer leaves were preferred over inner leaves and upper leaf sections preferred over lower leaf sections as egg-laying sites by adults. Implications of the results in the management of T. tabaci are discussed. PMID:18767744

  17. Evaluation of onion cultivars for resistance to onion thrips (Thysanoptera: Thripidae) and Iris yellow spot virus.

    PubMed

    Diaz-Montano, John; Fuchs, Marc; Nault, Brian A; Shelton, Anthony M

    2010-06-01

    Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), a worldwide pest of onion, Allium cepa L., can reduce onion yield by > 50% and be even more problematic when it transmits Iris yellow spot virus (family Bunyaviridae, genus Tospovirus, IYSV). Because T. tabaci is difficult to control with insecticides and other strategies, field studies on onion, Allium cepa L., resistance to T. tabaci and IYSV were conducted in 2007 and 2008 in two locations in New York state. Forty-nine cultivars were evaluated for resistance by counting the number of larvae weekly and recording leaf damage. In another experiment, the impact of T. tabaci and IYSV on plant growth and yield was examined by spraying half of the plants with an insecticide. Eleven of the 49 cultivars had very little leaf damage and were considered resistant to T. tabaci. Visual assessment indicated that all resistant cultivars had yellow-green- colored foliage, whereas the other 38 had blue-green- colored foliage. The visual assessment of color agreed with data on color taken with a HunterLab Ultra Scan XE colorimeter. The onions 'Colorado 6' and 'NMSU 03-52-1' had the lowest numbers of T. tabaci, suggesting strong antibiosis and/or antixenosis. The other nine cultivars had variable numbers of T. tabaci, indicating a possible combination of categories of resistance. In the nonprotected treatments there were significant reductions in plant height and plant weight in most of the resistant cultivars, but there were reductions in bulb weight only in a few of them. The average of plants infected with IYSV was 10% in 2007 and 60% in 2008. Our findings indicate potential for developing onion resistance to T. tabaci as part of an overall integrated pest management strategy but suggest difficulties in identifying resistance to IYSV. PMID:20568640

  18. Investigating alternatives to traditional insecticides: effectiveness of entomopathogenic fungi and Bacillus thuringiensis against citrus thrips and avocado thrips (Thysanoptera: Thripidae).

    PubMed

    Zahn, Deane K; Morse, Joseph G

    2013-02-01

    Citrus thrips, Scirtothrips citri (Moulton) (Thysanoptera: Thripidae), is a plant-feeding pest most widely recognized for causing damage to citrus (Citrus spp. L. [Rutaceae]) and mango (Mangifera indica L. [Anacardiaceae]) fruits. This insect has recently broadened its known host range to become a significant pest of California grown blueberries. Avocado thrips, Scirtothrips. perseae Nakahara (Thysanoptera: Thripidae), is a recent, invasive pest of California avocados, Persea americana Mill. (Laurales: Lauraceae). Effective alternatives to traditional pesticides are desirable for both pests to reduce impacts on natural enemies and broaden control options in an effort to minimize pesticide resistance via rotation of control materials. We evaluated Bacillus thuringiensis (Bt) subsp. israelensis proteins (Cyt 1A and Cry 11A, activated and inactivated) and multiple strains (GHA, 1741ss, SFBb1, S44ss, NI1ss, and 3769ss) of Beauveria bassiana (Balsamo) Vuillemin against both species. Avocado thrips and citrus thrips were not susceptible to either Bt protein tested, regardless of activation status. All strains of B. bassiana were able to infect both avocado thrips and citrus thrips. However, the commercially available GHA strain was the most effective strain against both species and had a faster rate of infection then the other strains tested. Citrus thrips were more susceptible than avocado thrips to all B. bassiana strains (LC50 and LC95 of 8.6 x 10(4) and 4.8 x 10(6) conidia per ml for citrus thrips, respectively). Investigation of citrus thrips field control using the GHA strain of B. bassiana is therefore justified. PMID:23448016

  19. Investigating alternatives to traditional insecticides: effectiveness of entomopathogenic fungi and Bacillus thuringiensis against citrus thrips and avocado thrips (Thysanoptera: Thripidae).

    PubMed

    Zahn, Deane K; Morse, Joseph G

    2013-02-01

    Citrus thrips, Scirtothrips citri (Moulton) (Thysanoptera: Thripidae), is a plant-feeding pest most widely recognized for causing damage to citrus (Citrus spp. L. [Rutaceae]) and mango (Mangifera indica L. [Anacardiaceae]) fruits. This insect has recently broadened its known host range to become a significant pest of California grown blueberries. Avocado thrips, Scirtothrips. perseae Nakahara (Thysanoptera: Thripidae), is a recent, invasive pest of California avocados, Persea americana Mill. (Laurales: Lauraceae). Effective alternatives to traditional pesticides are desirable for both pests to reduce impacts on natural enemies and broaden control options in an effort to minimize pesticide resistance via rotation of control materials. We evaluated Bacillus thuringiensis (Bt) subsp. israelensis proteins (Cyt 1A and Cry 11A, activated and inactivated) and multiple strains (GHA, 1741ss, SFBb1, S44ss, NI1ss, and 3769ss) of Beauveria bassiana (Balsamo) Vuillemin against both species. Avocado thrips and citrus thrips were not susceptible to either Bt protein tested, regardless of activation status. All strains of B. bassiana were able to infect both avocado thrips and citrus thrips. However, the commercially available GHA strain was the most effective strain against both species and had a faster rate of infection then the other strains tested. Citrus thrips were more susceptible than avocado thrips to all B. bassiana strains (LC50 and LC95 of 8.6 x 10(4) and 4.8 x 10(6) conidia per ml for citrus thrips, respectively). Investigation of citrus thrips field control using the GHA strain of B. bassiana is therefore justified.

  20. Temporal dynamics of iris yellow spot virus and its vector, Thrips tabaci (Thysanoptera: Thripidae), in seeded and transplanted onion fields.

    PubMed

    Hsu, Cynthia L; Hoepting, Christine A; Fuchs, Marc; Shelton, Anthony M; Nault, Brian A

    2010-04-01

    Onion thrips, Thrips tabaci (Lindeman) (Thysanoptera: Thripidae), can reduce onion bulb yield and transmit iris yellow spot virus (IYSV) (Bunyaviridae: Tospovirus), which can cause additional yield losses. In New York, onions are planted using seeds and imported transplants. IYSV is not seed transmitted, but infected transplants have been found in other U.S. states. Transplants are also larger than seeded onions early in the season, and thrips, some of which may be viruliferous, may preferentially colonize larger plants. Limited information is available on the temporal dynamics of IYSV and its vector in onion fields. In 2007 and 2008, T. tabaci and IYSV levels were monitored in six seeded and six transplanted fields. We found significantly more thrips in transplanted fields early in the season, but by the end of the season seeded fields had higher levels of IYSV. The percentage of sample sites with IYSV-infected plants remained low (<12%) until August, when infection levels increased dramatically in some fields. The densities of adult and larval thrips in August and September were better predictors of final IYSV levels than early season thrips densities. For 2007 and 2008, the time onions were harvested may have been more important in determining IYSV levels than whether the onions were seeded or transplanted. Viruliferous thrips emigrating from harvested onion fields into nonharvested ones may be increasing the primary spread of IYSV in late-harvested onions. Managing T. tabaci populations before harvest, and manipulating the spatial arrangement of fields based on harvest date could mitigate the spread of IYSV.

  1. Overwintering locations and hosts for onion thrips (Thysanoptera: Thripidae) in the onion cropping ecosystem in New York.

    PubMed

    Larentzaki, E; Shelton, A M; Musser, F R; Nault, B A; Plate, J

    2007-08-01

    Identifying locations where onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), overwinter and subsequently disperse is important for designing control strategies. In upstate New York from 2003 through 2006, potential overwintering sites in the commercial onion, Allium cepa L., cropping system were investigated early in the spring before onion seedling emergence and again late in the season after onions were harvested. Onion thrips adults were sampled directly from the soil and indirectly from the soil by using emergence cages. Sampling locations included onion field interiors and edges and areas outside of these fields, including woods. Host material sampled included onion culls; volunteer onions, which sprout from cull onions left behind after harvest; and weeds. Onion thrips adults were found in all sections of onion fields and in locations outside of onion fields, with the fewest emerging from woods. Emergence began in early May and extended into June. Peak emergence occurred during the last half of May, at which time 50-75% of the population had emerged. Adults colonized volunteer onions as early as late March and as late as mid-November. No adults were found overwintering in onion cull piles. Adults also colonized several weed species, especially pigweed, Amaranthus hybridis L., and lambsquarters, Chenopodium album L., late in the fall. Our results indicate that onion thrips adults overwinter in the soil within and near onion fields and that they probably colonize volunteer onion plants before subsequent generations infest the onion crop in the spring. Volunteer onions and weeds also provide onion thrips with a host after onions are harvested. Consequently, onion thrips management strategies should include tactics that reduce volunteer onion and weed abundance.

  2. Evaluating an Action Threshold-Based Insecticide Program on Onion Cultivars Varying in Resistance to Onion Thrips (Thysanoptera: Thripidae).

    PubMed

    Nault, Brian A; Huseth, Anders S

    2016-08-01

    Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), is a highly destructive pest of onion, Allium cepa L., and its management relies on multiple applications of foliar insecticides. Development of insecticide resistance is common in T. tabaci populations, and new strategies are needed to relax existing levels of insecticide use, but still provide protection against T. tabaci without compromising marketable onion yield. An action threshold-based insecticide program combined with or without a thrips-resistant onion cultivar was investigated as an improved approach for managing T. tabaci infestations in commercial onion fields. Regardless of cultivar type, the average number of insecticide applications needed to manage T. tabaci infestations in the action-threshold based program was 4.3, while the average number of sprays in the standard weekly program was 7.2 (a 40% reduction). The mean percent reduction in numbers of applications following the action threshold treatment in the thrips-resistant onion cultivar, 'Advantage', was 46.7% (range 40-50%) compared with the standard program, whereas the percentage reduction in applications in action threshold treatments in the thrips-susceptible onion cultivar, 'Santana', was 34.3% (range 13-50%) compared with the standard program, suggesting a benefit of the thrips-resistant cultivar. Marketable bulb yields for both 'Advantage' and 'Santana' in the action threshold-based program were nearly identical to those in the standard program, indicating that commercially acceptable bulb yields will be generated with fewer insecticide sprays following an action threshold-based program, saving money, time and benefiting the environment. PMID:27329626

  3. Potential new insecticides for the control of western flower thrips (Thysanoptera: Thripidae) on sweet pepper, tomato, and lettuce.

    PubMed

    Broughton, S; Herron, G A

    2009-04-01

    New pesticides are required to maintain effective resistance management strategies for control of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). We tested the efficacy of acetamiprid, and thiamethoxam, two neonicotinoids that represent a newer class of insecticides for the control of thrips. We also tested chlorfenapyr, a pyrrol compound, and a lower than registered rate of the biopesticide spinosad. Laboratory bioassays were used to predict the relative efficacy of insecticides against F. occidentalis and to forecast likely field rates. Two doses within the calculated LC99.99 range were used to predict field rates and trial rates of 0.5 g and 1.0 active ingredient (AI)/liter acetamiprid, 0.025 and 0.05 g (AI)/liter chlorfenapyr, 0.3 and 0.6 g (AI)/liter thiamethoxam, and 0.01 g (AI)/ liter spinosad were tested in the greenhouse against pepper, lettuce, and tomato. With the exception of acetamiprid, field trial doses predicted from laboratory bioassay translated to effective field efficacy. All products controlled F. occidentalis at the rates trialed and so have potential to augment current chemical controls. Increasing mortality correlated with increasing acetamiprid concentration in a greenhouse lettuce trial, suggesting that the higher trial rate (1.0 g [AI]/liter) may be required in some lettuce crops. The lower than registered (0.01 g [AI]/liter) rate of spinosad also significantly reduced F. occidentalis numbers and is a viable control option that may be useful in specific integrated pest management programs. The implications of introducing neonicotinoids into existing insecticide resistance management strategies for F. occidentalis are discussed. PMID:19449645

  4. Evaluating an Action Threshold-Based Insecticide Program on Onion Cultivars Varying in Resistance to Onion Thrips (Thysanoptera: Thripidae).

    PubMed

    Nault, Brian A; Huseth, Anders S

    2016-08-01

    Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), is a highly destructive pest of onion, Allium cepa L., and its management relies on multiple applications of foliar insecticides. Development of insecticide resistance is common in T. tabaci populations, and new strategies are needed to relax existing levels of insecticide use, but still provide protection against T. tabaci without compromising marketable onion yield. An action threshold-based insecticide program combined with or without a thrips-resistant onion cultivar was investigated as an improved approach for managing T. tabaci infestations in commercial onion fields. Regardless of cultivar type, the average number of insecticide applications needed to manage T. tabaci infestations in the action-threshold based program was 4.3, while the average number of sprays in the standard weekly program was 7.2 (a 40% reduction). The mean percent reduction in numbers of applications following the action threshold treatment in the thrips-resistant onion cultivar, 'Advantage', was 46.7% (range 40-50%) compared with the standard program, whereas the percentage reduction in applications in action threshold treatments in the thrips-susceptible onion cultivar, 'Santana', was 34.3% (range 13-50%) compared with the standard program, suggesting a benefit of the thrips-resistant cultivar. Marketable bulb yields for both 'Advantage' and 'Santana' in the action threshold-based program were nearly identical to those in the standard program, indicating that commercially acceptable bulb yields will be generated with fewer insecticide sprays following an action threshold-based program, saving money, time and benefiting the environment.

  5. Overwintering locations and hosts for onion thrips (Thysanoptera: Thripidae) in the onion cropping ecosystem in New York.

    PubMed

    Larentzaki, E; Shelton, A M; Musser, F R; Nault, B A; Plate, J

    2007-08-01

    Identifying locations where onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), overwinter and subsequently disperse is important for designing control strategies. In upstate New York from 2003 through 2006, potential overwintering sites in the commercial onion, Allium cepa L., cropping system were investigated early in the spring before onion seedling emergence and again late in the season after onions were harvested. Onion thrips adults were sampled directly from the soil and indirectly from the soil by using emergence cages. Sampling locations included onion field interiors and edges and areas outside of these fields, including woods. Host material sampled included onion culls; volunteer onions, which sprout from cull onions left behind after harvest; and weeds. Onion thrips adults were found in all sections of onion fields and in locations outside of onion fields, with the fewest emerging from woods. Emergence began in early May and extended into June. Peak emergence occurred during the last half of May, at which time 50-75% of the population had emerged. Adults colonized volunteer onions as early as late March and as late as mid-November. No adults were found overwintering in onion cull piles. Adults also colonized several weed species, especially pigweed, Amaranthus hybridis L., and lambsquarters, Chenopodium album L., late in the fall. Our results indicate that onion thrips adults overwinter in the soil within and near onion fields and that they probably colonize volunteer onion plants before subsequent generations infest the onion crop in the spring. Volunteer onions and weeds also provide onion thrips with a host after onions are harvested. Consequently, onion thrips management strategies should include tactics that reduce volunteer onion and weed abundance. PMID:17849870

  6. Temporal dynamics of iris yellow spot virus and its vector, Thrips tabaci (Thysanoptera: Thripidae), in seeded and transplanted onion fields.

    PubMed

    Hsu, Cynthia L; Hoepting, Christine A; Fuchs, Marc; Shelton, Anthony M; Nault, Brian A

    2010-04-01

    Onion thrips, Thrips tabaci (Lindeman) (Thysanoptera: Thripidae), can reduce onion bulb yield and transmit iris yellow spot virus (IYSV) (Bunyaviridae: Tospovirus), which can cause additional yield losses. In New York, onions are planted using seeds and imported transplants. IYSV is not seed transmitted, but infected transplants have been found in other U.S. states. Transplants are also larger than seeded onions early in the season, and thrips, some of which may be viruliferous, may preferentially colonize larger plants. Limited information is available on the temporal dynamics of IYSV and its vector in onion fields. In 2007 and 2008, T. tabaci and IYSV levels were monitored in six seeded and six transplanted fields. We found significantly more thrips in transplanted fields early in the season, but by the end of the season seeded fields had higher levels of IYSV. The percentage of sample sites with IYSV-infected plants remained low (<12%) until August, when infection levels increased dramatically in some fields. The densities of adult and larval thrips in August and September were better predictors of final IYSV levels than early season thrips densities. For 2007 and 2008, the time onions were harvested may have been more important in determining IYSV levels than whether the onions were seeded or transplanted. Viruliferous thrips emigrating from harvested onion fields into nonharvested ones may be increasing the primary spread of IYSV in late-harvested onions. Managing T. tabaci populations before harvest, and manipulating the spatial arrangement of fields based on harvest date could mitigate the spread of IYSV. PMID:20388253

  7. Population dynamics of Scirtothrips dorsalis (Thysanoptera: Thripidae) and other thrips species on two ornamental host plant species in Southern Florida.

    PubMed

    Mannion, Catharine M; Derksen, Andrew I; Seal, Dakshina R; Osborne, Lance S; Martin, Cliff G

    2014-08-01

    Since its 2005 introduction into the United States, chilli thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae), has become a problematic pest of agronomic, vegetable, fruit, and ornamental plants. Knowledge of its population dynamics may help managers better monitor and control S. dorsalis. Population estimates were recorded for S. dorsalis and other thrips species on Knock-Out rose (Rosa 'Radrazz') and green buttonwood (Conocarpus erectus L.) from July 2007 to September 2008 in two field plots (one per plant species) in Homestead, FL. Yellow sticky card traps and samples of terminals, flowers, buds, and leaves were collected. S. dorsalis accounted for 95% of all thrips individuals collected from plants and 84% from traps with the remainder including at least 18 other thrips species. More thrips were caught on or flying near rose plants (47,438) than on or near buttonwoods (5,898), and on-plant densities of S. dorsalis appeared higher for rose than for buttonwood. Compared with rose leaves, rose buds, terminals, and flowers each had higher numbers of S. dorsalis, and buds and terminals had higher densities. On each host plant species, S. dorsalis density fluctuated over time with peaks in the late spring, summer, and fall, but populations were consistently low in the late winter and early spring. On roses, increased plant damage ratings correlated with reduced numbers of flowers and buds, reduced mean flower areas, and increased on-plant number and density of S. dorsalis. There were positive correlations over time between S. dorsalis density and plant damage rating for rose flowers (R = 0.78; P = 0.0003) and for buttonwood terminals (R = 0.90; P = 0.0001). Yellow sticky card traps were effective for monitoring S. dorsalis and may be especially useful and economically justified for the most susceptible hosts, but they also work well for less susceptible hosts. A good S. dorsalis scouting program should hence consider trap catches and symptoms such as leaf

  8. Performance of arrhenotokous and thelytokous Thrips tabaci (Thysanoptera: Thripidae) on onion and cabbage and its implications on evolution and pest management.

    PubMed

    Li, Xiao-Wei; Fail, Jozsef; Wang, Ping; Feng, Ji-Nian; Shelton, A M

    2014-08-01

    Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), is an important pest on onion and cabbage. Two reproductive modes--arrhenotoky and thelytoky--are found in this species and co-occur in the field. We compared life table traits between arrhenotokous and thelytokous T. tabaci on cabbage and onion. Experiments were conducted in cages to determine which reproductive mode is more competitive. Additionally, host adaption of the arrhenotokous and thelytokous T. tabaci between onion and cabbage was investigated. On onion, arrhenotokous T. tabaci performed better than thelytokous T. tabaci, while on cabbage the opposite occurred. When comparing life table and demographic growth parameters (net reproductive rates R(o), mean generation time T, the intrinsic rate of natural increase r(m), finite rate of increase A, and population doubling time T(d)) on different host plants, we found that arrhenotokous T. tabaci performed better on onion than on cabbage, whereas thelytokous T. tabaci performed better on cabbage than on onion. Host-related performance differences in this species suggest that the divergence between two reproductive modes might be associated with host adaption. Pest management strategies for this global pest should recognize that the two reproductive modes can impact population dynamics on different crops.

  9. Postharvest control of western flower thrips (Thysanoptera: Thripidae) and California red scale (Hemiptera: Diaspididae) with ethyl formate and its impact on citrus fruit quality.

    PubMed

    Pupin, Francine; Bikoba, Veronique; Biasi, William B; Pedroso, Gabriel M; Ouyang, Yuling; Grafton-Cardwell, Elizabeth E; Mitcham, Elizabeth J

    2013-12-01

    The postharvest control of arthropod pests is a challenge that the California citrus industry must overcome when exporting fruit overseas. Currently, methyl bromide fumigation is used to control postharvest pests on exported citrus, but it may soon be unavailable because of use restrictions and cost of this health-hazard ozone-depleting chemical. Ethyl formate is a natural plant volatile and possible alternative to methyl bromide in postharvest insect control. The objectives of this study were 1) to evaluate the mortality of third instar California red scale [Aonidiella aurantii (Maskell)] (Hemiptera: Diaspididae) and adult western flower thrips [Frankliniella occidentalis (Pergande)] (Thysanoptera: Thripidae) under a wide range of ethyl formate concentrations, 2) to determine the ethyl formate concentration required to reach a Probit 9 level of control for both pests, and 3) to test the effects of ethyl formate fumigation on the quality of navel oranges [Citrus sinensis (L.) Osbeck] and lemons [Citrus limon (L.) Burman f.] at 24 h after fumigation, and at different time periods to simulate shipping plus storage (5 wk at 5 degrees C), and shipping, storage, handling, and shelf-life (5 wk at 5 degrees C, plus 5 d at 15 degrees C, and 2 d at 20 degrees C). The results indicate that ethyl formate is a promising alternative to methyl bromide for the California citrus industry, because of successful control of adult western flower thips and third instar California red scale and no deleterious effect on fruit quality at any of the evaluated periods and quality parameters.

  10. Population Dynamics of Frankliniella bispinosa (Thysanoptera: Thripidae) and the Predator Orius insidiosus (Hemiptera: Anthocoridae) as Influenced by Flower Color of Lagerstroemia (Lythraceae).

    PubMed

    Funderburk, Charles; Funderburk, Joe; Tyler-Julian, Kara; Srivastava, Mrittunjai; Knox, Gary; Andersen, Peter; Adkins, Scott

    2015-06-01

    Crapemyrtle is a common landscape planting that is a resource subsidy for beneficial insects. Field studies were conducted to determine the influence of crapemyrtle flower color on the population abundances and predator-prey dynamics of the herbivorous Frankliniella species and the predator Orius insidiosus. Adults and immatures of predator and prey were highly anthophilous, preferring white 'Acoma' flowers compared with lavender 'Apalachee', red 'Carolina Beauty', and pink 'Choctaw'. The predator was aggregated with its prey in a density-dependent manner: the adults by preferring the crapemyrtle clones also preferred by the thrips and the nymphs by direct tracking or as a function of increased prey and fecundity. Acoma was best for preference and buildup of O. insidiosus populations, and it was the only clone where there was no buildup in thrips populations. Two species of Karnyothrips (Thysanoptera: Phlaoethripidae), predators of small insects, were common in Tillandsia usneoides, an epiphyte on the crapemyrtle. Crapemyrtle is a bridge to enhance populations of O. insidiosus during summer months when there are few other hosts in the southern USA. PMID:26313973

  11. Thysanoptera (Thrips) Within Citrus Orchards in Florida: Species Distribution, Relative and Seasonal Abundance Within Trees, and Species on Vines and Ground Cover Plants

    PubMed Central

    Childers, Carl C.; Nakahara, Sueo

    2006-01-01

    Seven citrus orchards on reduced to no pesticide spray programs were sampled for Thysanoptera in central and south central Florida. Inner and outer canopy leaves, fruits, twigs, trunk scrapings, vines and ground cover plants were sampled monthly between January 1995 and January 1996. Thirty-six species of thrips were identified from 2,979 specimens collected from within citrus tree canopies and 18,266 specimens from vines and ground cover plants within the seven citrus orchards. The thrips species included seven predators [Aleurodothrips fasciapennis (Franklin), Karnyothrips flavipes (Jones), K. melaleucus (Bagnall), Leptothrips cassiae (Watson), L. macroocellatus (Watson), L. pini (Watson), and Scolothrips sexmaculatus (Pergande)] 21 plant feeding species [Anaphothrips n. sp., Arorathrips mexicanus (Crawford), Aurantothrips orchidaceous (Bagnall), Baileyothrips limbatus (Hood), Chaetanaphothrips orchidii (Moulton), Danothrips trifasciatus (Sakimura), Echinothrips americanus (Morgan), Frankliniella bispinosa (Morgan), F. cephalica (Crawford), F. fusca (Hinds), F. gossypiana (Hood), Frankliniella sp. (runneri group), Haplothrips gowdeyi (Franklin), Heliothrips haemorrhoidalis (Bouché), Leucothrips piercei (Morgan), Microcephalothrips abdominalis (Crawford), Neohydatothrips floridanus (Watson), N. portoricensis (Morgan), Pseudothrips inequalis (Beach), Scirtothrips sp., and Thrips hawaiiensis (Morgan)]; and eight fungivorous feeding species [Adraneothrips decorus (Hood), Hoplandrothrips pergandei (Hinds), Idolothripinae sp., Merothrips floridensis (Watson), M. morgani (Hood), Neurothrips magnafemoralis (Hinds), Stephanothrips occidentalis Hood and Williams, and Symphyothrips sp.]. Only F. bispinosa, C. orchidii, D. trifasciatus, and H. haemorrhoidalis have been considered economic pests on Florida citrus. Scirtothrips sp. and T. hawaiiensis were recovered in low numbers within Florida citrus orchards. Both are potential pest species to citrus and possibly other

  12. Impact of insecticide efficacy on developing action thresholds for pest management: a case study of onion thrips (Thysanoptera: Thripidae) on onion.

    PubMed

    Nault, Brian A; Shelton, Anthony M

    2010-08-01

    An action threshold (AT) is one of the most important decision-making elements in integrated pest management. Unlike economic thresholds, ATs are not typically derived from an economic injury level model, but they are more commonly used. ATs may be identified from research-based, pest-crop relationships, but they also may be based on experience. ATs may be adjusted depending on, e.g., weather and plant variety, but modifying ATs to accommodate differences in insecticide efficacy has received little attention. To examine this point, several combinations of ATs and insecticides were evaluated against onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), a major pest of onion (Allium cepa L.). Studies were conducted in New York onion fields from 2006 to 2008 by using registered insecticides for T. tabaci on onions. We hypothesized that the most efficacious insecticides would provide acceptable control of thrips populations regardless of AT (one, three, and five thrips per leaf), whereas less effective products would only control populations using the lowest AT (one thrips per leaf). Results indicated that T. tabaci infestations were managed effectively when spinetoram was applied after a three larvae per leaf threshold, but not when using lambda-cyhalothrin, methomyl or formetanate hydrochloride. However, T. tabaci infestations were managed well when methomyl and formetanate hydrochloride were applied after a one larva per leaf threshold. T. tabaci infestations were never controlled using lambda-cyhalothrin, regardless of the AT used. None of the products reduced T. tabaci populations to an acceptable level when applied at a five larvae per leaf threshold. Implications of adjusting ATs based on efficacy of different insecticides are discussed. PMID:20857743

  13. Characterization of resistance, evaluation of the attractiveness of plant odors, and effect of leaf color on different onion cultivars to onion thrips (Thysanoptera: Thripidae).

    PubMed

    Diaz-Montano, John; Fail, József; Deutschlander, Mark; Nault, Brian A; Shelton, Anthony M

    2012-04-01

    Onion thrips, Thrips tabaci Lindeman (Thysanoptera: Thripidae), is a worldwide pest of onion, Allium cepa L. In field studies on onion resistance conducted in 2007 and 2008 using 49 cultivars, 11 showed low leaf damage by T. tabaci. In laboratory studies, the 11 cultivars, along with two susceptible checks and four additional cultivars, were evaluated to characterize resistance to T. tabaci and to determine if color and/or light reflectance were associated with resistance to T tabaci. No-choice tests were performed with adults and the numbers of eggs and larvae were counted on each cultivar after three and 10 d, respectively. In choice tests in which all cultivars were planted together in a circle in a single pot, 100 adults were released and the number of adults on each plant was evaluated 24 h later. The behavioral response of walking T. tabaci adults to plant odors was studied in a glass Y-tube olfactometer. The reflectance spectrum of leaves was measured using a UV-VIS spectrophotometer. Results indicate that resistant cultivars showed an intermediate-high antibiotic effect to T. tabaci and all of them showed a very strong antixenotic effect. There were no significant preferences in the response of walking T. tabaci adults to plant odors. The two susceptible cultivars had the highest values of leaf reflectance for the first (275-375 nm) and second (310-410 nm) theoretical photopigment-system of T. tabaci, and these values were significantly different from most resistant cultivars. These results suggest a strong response of T. tabaci to onion cultivars with higher reflectance in the ultraviolet range (270-400 nm). Overall, these results appear promising in helping to identify categories of resistance to T. tabaci in onions that can be used in breeding programs.

  14. Thiamethoxam resistance selected in the western flower thrips Frankliniella occidentalis (Thysanoptera: Thripidae): cross-resistance patterns, possible biochemical mechanisms and fitness costs analysis.

    PubMed

    Gao, Cong-Fen; Ma, Shao-Zhi; Shan, Cai-Hui; Wu, Shun-Fan

    2014-09-01

    The western flower thrips (WFT) Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), an important pest of various crops in the world, has invaded China since 2003. To understand the risks and to determine possible mechanisms of resistance to thiamethoxam in WFT, a resistant strain was selected under the laboratory conditions. Cross-resistance and the possible biochemical resistance mechanisms were investigated in this study. A 15.1-fold thiamethoxam-resistant WFT strain (TH-R) was established after selection for 55 generations. Compared with the susceptible strain (TH-S), the selected TH-R strain showed extremely high level cross-resistance to imidaclothiz (392.1-fold) and low level cross-resistance to dinotefuran (5.7-fold), acetamiprid (2.9-fold) and emamectin benzoate (2.1-fold), respectively. No cross-resistance to other fourteen insecticides was detected. Synergism tests showed that piperonyl butoxide (PBO) and triphenyl phosphate (TPP) produced a high synergism of thiamethoxam effects in the TH-R strain (2.6- and 2.6-fold respectively). However, diethyl maleate (DEM) did not act synergistically with thiamethoxam. Biochemical assays showed that mixed function oxidase (MFO) activities and carboxylesterase (CarE) activity of the TH-R strain were 2.8- and 1.5-fold higher than that of the TH-S strain, respectively. When compared with the TH-S strain, the TH-R strain had a relative fitness of 0.64. The results show that WFT develops resistance to thiamethoxam after continuous application and thiamethoxam resistance had considerable fitness costs in the WFT. It appears that enhanced metabolism mediated by cytochrome P450 monooxygenases and CarE was a major mechanism for thiamethoxam resistance in the WFT. The use of cross-resistance insecticides, including imidaclothiz and dinotefuran, should be avoided for sustainable resistance management. PMID:25175655

  15. Efficacy of entomopathogenic nematode Steinernema feltiae (Rhabditida: Steinernematidae) as influenced by Frankliniella occidentalis (Thysanoptera: Thripidae) developmental stage and host plant stage.

    PubMed

    Buitenhuis, R; Shipp, J L

    2005-10-01

    Entomopathogenic nematodes were investigated as an alternative biological control strategy for western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), in ornamental greenhouse crops, by using potted chrysanthemum as a model crop. The susceptibility of various life stages of F. occidentalis to different concentrations of the nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) was investigated in petri dish bioassays. This was followed with trials using potted chrysanthemums comparing the efficacy of nematode application to plants in vegetative (exposed habitat) versus flowering (cryptic habitat) stages. In both trials, the effect of the wetting agent Agral 90 (nonylphenoxy polyethoxyethanol), which is used in combination with the nematode spray, on F. occidentalis mortality was assessed. In petri dish trials, the prepupae and pupae were the most susceptible developmental stages of F. occidentalis to infection by S. feltiae. First and second instars were killed by very high rates of nematodes (> or =20,000 infective juveniles per milliliter), but corrected mortality was only approximately 28-37%. No significant mortality was observed for adult thrips. Results from the petri dish trials were confirmed on chrysanthemum plants. Foliar application of S. feltiae did not result in significant mortality in larvae or adults. No significant differences in efficacy were detected by application of nematodes on vegetative versus flowering chrysanthemum. Agral 90 had a significant impact on mortality on the first stage larvae and prepupae in the petri dish trials but not in the plant trials. Thrips control by S. feltiae in greenhouses may be partly or completely due to prepupal and pupal mortality. PMID:16334313

  16. Insecticidal Activity of α-Methylene-γ-butyrolactone against Several Insect Pests.

    PubMed

    Datta, P K; Kim, C S; Hara, T; Itoh, E; Horiike, M

    1999-01-01

    α-Methylene-γ-butyrolactone (tulipalin A), which has been found to possess effective insecticidal activity against Thrips palmi (Thysanoptera; Thripinae), was examined on several insect pests. This compound caused high mortality against thrips species such as Frankliniella occidentallis and Frankliniella intonsa. In addition, some mortality was observed against other agricultural pest species. It is considered that α-methylene-γ-butyrolactone has a wide spectrum of insecticidal activity.

  17. The male reproductive system of Zorotypus caudelli Karny (Zoraptera): Sperm structure and spermiogenesis.

    PubMed

    Dallai, R; Mercati, D; Gottardo, M; Machida, R; Mashimo, Y; Beutel, R G

    2011-11-01

    Considering the overall uniformity of the morphology of Zoraptera, the structural diversity of the male genital system is remarkable. Structures related to the male reproductive system of Zorotypus caudelli differ profoundly from those of Zorotypus hubbardi. The testes are elongated rather than spherical, the seminal vesicle is apparently absent, and the deferent ducts are very long. A feature shared by these two species and other zorapterans examined is that the two accessory glands are closely adherent to each other and form a single large structure, from which the ejaculatory duct originates. This is a potential zorapteran autapomorphy. Another feature possibly present in the groundplan of the order is the strong elongation of the sperm cells. This may be connected with a reproductive strategy of males trying to avoid re-mating of females with other males after the first copulation. The extremely long and coiled spermathecal duct of Z. caudelli and other zorapteran species is possibly correlated with the sperm elongation, and both features combined may result in a sexual isolating mechanism. The short duration of mating of Zorotypus barberi and Zorotypus gurneyi suggests that the male introduces sperm into the female tract up to the opening of the spermathecal duct using their long coiled aedeagus. A thick glycocalyx around the sperm in the distal part of the deferent ducts probably protects the sperm cells during their forward progression towards the long spermathecal duct, and is removed when they reach the apical receptacle. The spermatogenesis of Z. caudelli follows a pattern commonly found in insects, but differs distinctly from that of Z. hubbardi in the number of spermatids in each sperm cyst. An unusual and possibly autapomorphic feature of Z. caudelli is a disconnection of sub-tubules A and B at the level of microtubule doublets 1 and 6 of the mature sperm cells. It is conceivable that this results in a shorter period of sperm motility. The character combination found in different zorapteran species supports the view that the sperm, a very compact functional unit, does not evolve as a unit, but like in other more complex body regions, sperm components can also be modified independently from each other. This results in different mosaic patterns of plesiomorphic and derived features in a very compact entity in different species of the very small and otherwise uniform order Zoraptera. In Z. caudelli, for instance, the bi-layered acrosome and small accessory bodies are plesiomorphic states among several others, whereas the mitochondrial derivatives and the elongate nucleus are apparently derived conditions. Other combinations likely occur in other zorapteran species. Only few but noteworthy sperm characters indicate possible phylogenetic affinities of Zoraptera. A possible synapomorphic feature, the presence of dense laminae radiating in a cartwheel array between neighbouring centriolar triplets, is shared with Phasmatodea and Embioptera. Another potential synapomorphy shared with Phasmatodea is the presence of 17 protofilaments in the tubular wall of the outer accessory microtubules.

  18. New sericothripine thrips of South America (Thysanoptera, Thripidae, Neohydatothrips)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-seven species of Hydatothrips and Neohydatothrips occurring in South America are reviewed. Five new species of Neohydatothrips are described. An additional species from Asia, Neohydatothrips samayunkur Kudo, a pest of marigolds and various crops, has been transported via commerce into Europe,...

  19. Species-richness in Neotropical Sericothripinae (Thysanoptera: Thripidae).

    PubMed

    Lima, Élison Fabrício B; Mound, Laurence A

    2016-09-08

    Two of the three recognized genera of Sericothripinae are known from the Neotropics, and 14 new species from this area are here described in this subfamily. Illustrated keys are provided to females of seven species of Hydatothrips, and 41 species of Neohydatothrips, mainly from Brazil but including all recorded species south of the border between Mexico and USA. Plant species on which breeding has been recorded are indicated where possible, notes are provided on the few species of economic importance, and a key is appended to second instar larvae of seven species. Neohydatothrips burungae (Hood) stat. rev. and N. aztecus Johansen stat. rev. are recalled from synonymy with Neohydatothrips signifer (Priesner), and N. denigratus (De Santis) syn. n. is synonymized with N. burungae. Hydatothrips williamsi (Hood) comb. n. is relocated from Neohydatothrips, and as this produces a homonym in the genus, Hydatothrips tareei nom. nov. is proposed for Hydatothrips williamsi Mound & Tree from Australia.

  20. Species-richness in Neotropical Sericothripinae (Thysanoptera: Thripidae).

    PubMed

    Lima, Élison Fabrício B; Mound, Laurence A

    2016-01-01

    Two of the three recognized genera of Sericothripinae are known from the Neotropics, and 14 new species from this area are here described in this subfamily. Illustrated keys are provided to females of seven species of Hydatothrips, and 41 species of Neohydatothrips, mainly from Brazil but including all recorded species south of the border between Mexico and USA. Plant species on which breeding has been recorded are indicated where possible, notes are provided on the few species of economic importance, and a key is appended to second instar larvae of seven species. Neohydatothrips burungae (Hood) stat. rev. and N. aztecus Johansen stat. rev. are recalled from synonymy with Neohydatothrips signifer (Priesner), and N. denigratus (De Santis) syn. n. is synonymized with N. burungae. Hydatothrips williamsi (Hood) comb. n. is relocated from Neohydatothrips, and as this produces a homonym in the genus, Hydatothrips tareei nom. nov. is proposed for Hydatothrips williamsi Mound & Tree from Australia. PMID:27615957

  1. A new species of Danothrips from Southwestern China (Thysanoptera: Thripidae).

    PubMed

    Li, Yajin; Xie, Yonghui; Zhang, Hongrui

    2016-01-01

    Danothrips salicis sp. n. is described from young leaves of Salix sp. in Southwestern China. This species is similar to D. moundi, D. theifolii and D. trifasciatus, but can be distinguished by the colour of the fore wing, the median longitudinal split on tergite X of females, and in males by the situation of the median short thorn-like setae on tergite IX. PMID:27615912

  2. First description of the male of Yaobinthrips yangtzei (Thysanoptera: Thripidae).

    PubMed

    Li, Yajin; Xie, Yong-Hui; Zhang, Hongrui

    2016-01-01

    The monobasic Thripinae genus Yaobinthrips has been known only from females, and the objective here is to provide a description of the male. A member of the Frankliniella genus-group, the type species, yangtzei Zhang et al. (2010) was described from specimens taken in Sichuan Province of Southwestern China from the flowers of Dalbergia yunnanensis [Fabaceae]. In April, 2015 a sample of both sexes of this thrips species was taken from the white flowers of the same plant species, but in Yunnan Province. This plant is actually widespread in southwestern China in Yunnan, Sichuan, Guizhou Provinces and Guangxi Zhuang Autonomous Region. Provinces, growing at an elevation ranging from 1400 to 2200 meters, and flowering from April to May (Li et al. 2007). PMID:27395534

  3. Management of winter weeds affects Frankliniella fusca (Thysanoptera: Thripidae) dispersal.

    PubMed

    Beaudoin, A L P; Kennedy, G G

    2012-04-01

    Frankliniella fusca (Hinds) naturally disperses from winter weeds to crops in spring, causing direct and indirect damage. Field preparation before planting includes use of herbicides or cultivation to kill unwanted vegetation, which adversely affects F. fusca host plants and potentially influences F. fusca dispersal. Common chickweed, Stellaria media (L.), infested with F. fusca, was used as a model to study effects of timing and type of vegetation management on adult dispersal. Infested weeds were caged and F. fusca weekly dispersal was monitored using sticky traps. Weed management treatments performed at an early (14 April-11 May) or late (2 wk after early treatment) date consisted of glyphosate, paraquat, disking, hoeing, or untreated control. Late glyphosate and hoeing treatments resulted in cumulative dispersal statistically similar to or greater than from control plots. Compared with the control, significantly more F. fusca dispersed from the glyphosate and hoeing plots during the 3 wk after treatment. More thrips dispersed from the late paraquat treatment 1 wk post-application than from the control. Dispersal from the disked treatment and early paraquat treatment was similar to that of the control 1- to 3-wk post-treatment. Early treatments resulted in significantly smaller cumulative dispersal than the control in all but one instance. Late disking and paraquat treatments resulted in cumulative F. fusca captures that were statistically similar or less than that in the control. Winter weed management type and timing affect F. fusca dispersal magnitude and duration.

  4. [Taxonomic revision of the Haplothrips-Karnyothrips group (Thysanoptera: Phlaeothripidae)].

    PubMed

    Retana-Salazar, Axel P; Soto-Rodríguez, Gerardo A

    2007-06-01

    The generic group ("ensemble") Haplothrips-Karnyothrips is reviewed, following the most recently published criteria for distinguishing generic characters. We establish a new diagnosis for each genus. A review of a Central American collection is included and a new genus of Phlaeothripidae is described from the Central Pacific of Costa Rica from specimens collected on Cyperaceae flowers during the dry season. The genus can be distinguished by widely separated maxillary stylets, absent maxillary bridge, pelta shape and the setae B1, which measures two thirds of the tube length. We include a key based on characters of phylogenetic importance. PMID:19069772

  5. The occurrence and composition of thrips (Thysanoptera) species on leek.

    PubMed

    Pobozniak, M; Bujak, P; Rataj, S

    2006-01-01

    The aim of the present research work was to investigate the population density and species composition of thrips infesting crops of leek in south Poland. The flight activity of thrips was monitored using blue sticky traps and plant samples were taken to record the number of adult and larvae of thrips on leek. In 2004, the thrips were caught into blue sticky traps from the middle of June to the end of second decade of October. The first peak flight activity was noticed on the beginning of the third decade of July. The next peak flight activity was recorded in the middle and at the end of August. In 2004 the rapid growth of the numerousness of adult thrips was recorded at the third decade of September. The evident growth of the number of the adult thrips was continued until the third decade of October. Thrips larvae were observed from the second decade of September to the third decade of October. In 2005 the highest number of adult thrips on both cultivars was noticed at the third decade of July and this corresponded to a period of intensive flight activity. 2004, the most numerous species was Thrips tabaci Lindeman, which amounted to the 98.5% of the total number of collected thrips. The second most numerous species was Frankliniella intonsa Trybom (1.1%). In 2005, the most dominant was Frankliniella intonsa (Trybom) (78.3%). The percentage participation of Thrips tabaci Lindeman was 9.8%.

  6. The occurrence and species composition of thrips (Thysanoptera) on onion.

    PubMed

    Pobozniak, Maria; Palacz, Anna; Rataj, Agnieszka

    2007-01-01

    The aim of the present research work was to investigate the population density and species composition of thrips infesting crops of onion in South Poland. The flight activity of thrips was monitored using blue sticky traps and plant samples were taken to record the number of adult and Larvae of thrips on onion. In 2004 the thrips were caught into blue sticky traps from the start of June to the end of the first decade of September. The peak flight activity was noticed in the middle of July. In 2004 the significant growth of the numerousness of adult thrips on onion grown from seeds was recorded in the middle and in the third decade of August, whereas on onion grown from sets in the first decade of August. Thrips larvae were not observed during the whole vegetation season. In 2005, the thrips were caught into blue sticky traps form the half of June to the first decade of September. The peak flight activity was noticed in the first decade of August. In 2005 the rapid growth of the numerousness of adult thrips on onion grown from seeds was recorded in the third decade of July. The highest number of adult thrips on onion grown from sets was noticed at the beginning of August. Thrips larvae were observed on onion grown from seeds in the third decade of July and at the end of the second decade of August. In both years of observations the most numerous species was Frankliniella intonsa Tryb. The second most numerous species was Thrips tabaci Lindeman. In 2004, the most numerous species was predacious Aeolothrips intermedius Bagnall.

  7. An Evaluation of Frankliniella occidentalis (Thysanoptera: Thripidae) and Frankliniella intonsa (Thysanoptera: Thripidae) Performance on Different Plant Leaves Based on Life History Characteristics

    PubMed Central

    Li, Wei-Di; Zhang, Peng-Jun; Zhang, Jing-Ming; Zhang, Zhi-Jun; Huang, Fang; Bei, Ya-Wei; Lin, Wen-Cai; Lu, Yao-Bin

    2015-01-01

    To compare the performance of Frankliniella occidentalis (Pergande) and native Frankliniella intonsa (Trybom) on cucumber and tomato leaves in laboratory, life history characters were investigated, and life tables were constructed using the method of age-stage, two-sex table life. Compared with tomato leaf, there were shorter total preoviposition period (TPOP), higher fecundity, longer female longevity, and higher intrinsic rate of increase (r) of both F. occidentalis and F. intonsa on cucumber leaf. Meanwhile, on cucumber leaf, the shorter TPOP, higher fecundity, longer female longevity, and higher value of r were found on population of F. intonsa but on tomato leaf which were found on population of F. occidentalis. From above, cucumber leaf was the preference to population development of both F. occidentalis and F. intonsa compared with tomato leaf. Nevertheless, on cucumber leaf, population of F. intonsa would grow faster than that of F. occidentalis, which was the opposite on tomato leaf. As to the population development in fields, much more factors would be taken into account, such as pollen, insecticide resistance, and effects of natural enemies etc. PMID:25673049

  8. An evaluation of Frankliniella occidentalis (Thysanoptera: Thripidae) and Frankliniella intonsa (Thysanoptera: Thripidae) performance on different plant leaves based on life history characteristics.

    PubMed

    Li, Wei-Di; Zhang, Peng-Jun; Zhang, Jing-Ming; Zhang, Zhi-Jun; Huang, Fang; Bei, Ya-Wei; Lin, Wen-Cai; Lu, Yao-Bin

    2015-01-01

    To compare the performance of Frankliniella occidentalis (Pergande) and native Frankliniella intonsa (Trybom) on cucumber and tomato leaves in laboratory, life history characters were investigated, and life tables were constructed using the method of age-stage, two-sex table life. Compared with tomato leaf, there were shorter total preoviposition period (TPOP), higher fecundity, longer female longevity, and higher intrinsic rate of increase (r) of both F. occidentalis and F. intonsa on cucumber leaf. Meanwhile, on cucumber leaf, the shorter TPOP, higher fecundity, longer female longevity, and higher value of r were found on population of F. intonsa but on tomato leaf which were found on population of F. occidentalis. From above, cucumber leaf was the preference to population development of both F. occidentalis and F. intonsa compared with tomato leaf. Nevertheless, on cucumber leaf, population of F. intonsa would grow faster than that of F. occidentalis, which was the opposite on tomato leaf. As to the population development in fields, much more factors would be taken into account, such as pollen, insecticide resistance, and effects of natural enemies etc.

  9. Biology of Thripinema nicklewoodi (Tylenchida), an Obligate Frankliniella occidentalis (Thysanoptera) Parasite

    PubMed Central

    Mason, Judy M.; Heinz, Kevin M.

    2002-01-01

    Frankliniella occidentalis, a serious pest of agricultural crops, is difficult to manage because chemical and biological control measures frequently fail to affect F. occidentalis in their preferred microhabitats. Parasitism by the host-specific, entomopathogenic nematode Thripinema nicklewoodi may provide a much-needed alternative to current control strategies. Infection does not cause death of the host; rather, the result is sterilization that leads to suppression of F. occidentalis populations. We describe a simple rearing method and the results from studies aimed at providing details on its biology-both essential first steps to examining its biological control potential. All F. occidentalis life stages are susceptible to infection, but to varying degrees (most susceptible to least susceptible): female pupae, second instar larvae, first instar larvae, male pupae, adult females, adult males. Nematodes emerge from female and male F. occidentalis for approximately 15 and 9 days, with approximately 14 and 7 nematodes emerging per day, respectively. Females and males are short-lived outside of the host, with mean survival rates ranging between 7 and 86 hours. Transmission does not occur in the soil but rather on or within plant structures that are preferred microhabitats visited by F. occidentalis. Results from a dose-response study suggest that augmentative applications of T. nicklewoodi may be useful to generate increased infection rates and subsequent suppression of F. occidentalis populations. PMID:19265952

  10. Repellency of Plant Extracts against the Legume Flower Thrips Megalurothrips sjostedti (Thysanoptera: Thripidae)

    PubMed Central

    Abtew, Andnet; Subramanian, Sevgan; Cheseto, Xavier; Kreiter, Serge; Tropea Garzia, Giovanna; Martin, Thibaud

    2015-01-01

    Megalurothrips sjostedti Trybom is an important pest of cowpea (Vigna unguiculata L.) in Africa. To propose an alternative to chemical control, the repellency of 24 plant extracts was evaluated against adult female thrips of M. sjostedti in the laboratory. Plant extracts in ethanol were separately applied on a filter paper disk in a still air visual cue olfactometer. The results showed highly significant differences in repellency among extract type, concentration and their interactions. We classified the level of repellency into four categories as strong, good, moderate and weak or non- repellent based on hierarchical ascendant classification. We identified Piper nigrum, Cinnamomum zeylanicum, Cinnamomum cassia as strong repellents. Five extracts were classified as good, eight as moderate and the remaining eight extracts were weak or non-repellent. Repellency of the extracts increased with the concentration suggesting that the behavioral response of M. sjostedti was dose-dependent. Mono- and sesquiterpene hydrocarbon compounds from seven highly repellent extracts were identified by gas chromatography-mass spectrometry (GC/MS). The use of repellent extracts could be useful in developing integrated pest management strategies for thrips on legume crops. In this regard, the specific modes of action of the identified compounds need to be investigated to incorporate them into the existing crop protection strategies. PMID:26463406

  11. Repellency of Plant Extracts against the Legume Flower Thrips Megalurothrips sjostedti (Thysanoptera: Thripidae).

    PubMed

    Abtew, Andnet; Subramanian, Sevgan; Cheseto, Xavier; Kreiter, Serge; Garzia, Giovanna Tropea; Martin, Thibaud

    2015-01-01

    Megalurothrips sjostedti Trybom is an important pest of cowpea (Vigna unguiculata L.) in Africa. To propose an alternative to chemical control, the repellency of 24 plant extracts was evaluated against adult female thrips of M. sjostedti in the laboratory. Plant extracts in ethanol were separately applied on a filter paper disk in a still air visual cue olfactometer. The results showed highly significant differences in repellency among extract type, concentration and their interactions. We classified the level of repellency into four categories as strong, good, moderate and weak or non- repellent based on hierarchical ascendant classification. We identified Piper nigrum, Cinnamomum zeylanicum, Cinnamomum cassia as strong repellents. Five extracts were classified as good, eight as moderate and the remaining eight extracts were weak or non-repellent. Repellency of the extracts increased with the concentration suggesting that the behavioral response of M. sjostedti was dose-dependent. Mono- and sesquiterpene hydrocarbon compounds from seven highly repellent extracts were identified by gas chromatography-mass spectrometry (GC/MS). The use of repellent extracts could be useful in developing integrated pest management strategies for thrips on legume crops. In this regard, the specific modes of action of the identified compounds need to be investigated to incorporate them into the existing crop protection strategies. PMID:26463406

  12. One new species and two new records of the genus Aeolothrips from Iran (Insecta, Thysanoptera, Aeolothripidae)

    PubMed Central

    Alavi, Jalil; Awal, Mehdi Modarres; Fekrat, Lida; Minaei, Kambiz; Manzari, Shahab

    2016-01-01

    Abstract Aeolothrips gundeliae sp. n. is described, and two bicolored species of the same genus, Aeolothrips ericae Bagnall and Aeolothrips albithorax Pelikan are newly reported from northeast of Iran. Diagnostic characters are provided for each species as well as illustrations to distinguish these species. PMID:26884701

  13. Temporal and spatial distribution of an invasive thrips species Scirtothrips dorsalis (Thysanoptera: Thripidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Dispersion of a new invasive thrips species, chilli thrips Scirtothrips dorsalis Hood, was studied on three hosts, i.e., cotton (Gossypium hirsutum L.), peanut (Arachis hypogeal L.) and pepper (Capsicum annum L.) in the greenhouse and under field conditions in Homestead, Florida. The study of horizo...

  14. Sequential sampling plans for western flower thrips (Thysanoptera: Thripidae) on greenhouse cucumbers.

    PubMed

    Wang, K; Shipp, J L

    2001-04-01

    The development of cost-effective and reliable sampling programs for the management of western flower thrips, Frankliniella occidentalis (Pergande), on greenhouse cucumbers is important for getting growers to adopt economic injury levels and economic thresholds. The objectives of this study were to develop two sequential sampling plans. A fixed-precision sequential sampling plan was designed for estimating F. occidentalis adult density at a fixed-precision level on cucumber flowers. Also, a sequential sampling plan for classifying thrips population levels as below or above economic thresholds was developed to assist in decision making for the timing of pesticide applications. Both sequential sampling plans were validated using a resampling simulation technique on nine independent data sets ranging in density from 1.25 to 12.95 adults per flower. With the fixed-precision sampling plan, average means obtained in 100 repeated simulation runs were within the 95% CI of the estimated mean for all data sets. Appropriate levels of precision for the different population densities were recommended based on the simulation results. With sequential sampling for classifying the population levels of thrips in terms of an economic threshold, it has the advantage of requiring smaller sample sizes to determine the population status when the population densities differ greatly from the critical density (i.e., economic threshold). However, this plan needs a great number of samples when population density is close to the critical density. In this case, use of a combination of both sampling plans is recommended. PMID:11332857

  15. The first micropterous species of the southern European genus Kakothrips (Thysanoptera: Thripidae).

    PubMed

    Marullo, Rita; Ravazzi, Giorgio

    2016-01-01

    The European genus Kakothrips Williams includes seven species (ThripsWiki 2015) that are known to be flower-living mainly on Fabaceae plants. The genus is recorded across Europe from Morocco to England, and eastwards to Syria and Iran (zur Strassen 2003). Only K. pisivorus (Westwood) is known from northern Europe, and this is the senior synonym of the type species K. robustus (Uzel) (Collins 2010). Closely related to Frankliniella, the species share with the members of that genus the character states of ctenidia present on tergite VIII anterolateral to the spiracles, and a complete row of setae on both longitudinal veins of the fore wing. Also, the pronotal anteromarginal and anteroangular setae are half as long as the posteroangular setae. The character states of the genus Kakothrips include: ocellar setae pair III arising between posterior ocelli; fore tarsus with an apical tooth, laterally; pronotal posterior margin without a pair of small setae between the major posteromarginal setae. In some of the species the males bear a pair of stout tubercles laterally on tergite VIII, and sternites III-VI or III-VII of males have a transverse pore plate. All the described species are known only from macropterae, and they are similar to each other in structure. A few distinguishing characters include colour of body, fore wings and antennal segments; the shape, length and position of the fore tarsal tooth; size of body, antennal segments, and major setae; and in males, shape of sternal pore plates, and length of setae on tergite IX. PMID:27395885

  16. Next-generation DNA sequencing of the globally invasive plant pest, Scirtothrips dorsalis hood (Thysanoptera: Thripidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the highest profile thrips species to invade the U.S. in the last ten years is the chilli thrips. This thrips is difficult to identify due to few distinct morphological characters and molecular data suggest that it is actually a complex containing multiple, morphologically indistinguishable, ...

  17. Evaluation of Beauveria bassiana for management of citrus thrips (Thysanoptera: Thripidae) in California blueberries.

    PubMed

    Zahn, Deane K; Haviland, David R; Stanghellini, M E; Morsel, Joseph G

    2013-10-01

    Citrus thrips, Scirtothrips citri (Moulton), is a plant-feeding pest most widely recognized for causing damage to citrus and mango fruits. This insect has broadened its host range to become a significant pest of commercial blueberries grown in the San Joaquin Valley of California. We evaluated Beauveria bassiana (Balsamo) for control of citrus thrips in blueberries grown under two watering regimes (drip irrigation with and without overhead sprinklers) and using two fungal formulations (commercially available spores in suspension vs. colonized seed) over two sampling periods, that is, for two 3-d periods after treatment. We found significant differences in thrips densities as a function of water regime treatment and fungal formulation. Thrips levels were reduced significantly with both fungal treatments at 3 d after treatment, but at 6 d, only results with colonized seed differed from the control treatment. These data suggest entomopathogenic fungi might be useful for control of citrus thrips on blueberries in particular situations (in organic production or as a resistance management tool) but that traditional pesticides will likely remain the preferred management option. PMID:24224239

  18. Detection of Gene Flow from Sexual to Asexual Lineages in Thrips tabaci (Thysanoptera: Thripidae).

    PubMed

    Li, Xiao-Wei; Wang, Ping; Fail, Jozsef; Shelton, Anthony M

    2015-01-01

    Populations of Thrips tabaci are known to have two sympatric but genetically isolated reproductive modes, arrhenotoky (sexual reproduction) and thelytoky (asexual reproduction). Herein, we report behavioral, ecological and genetic studies to determine whether there is gene flow between arrhenotokous and thelytokous T. tabaci. We did not detect significant preference by arrhenotokous males to mate with females of a particular reproductive mode, nor did we detect significant behavioral differences between arrhenotokous males mated with arrhenotokous or thelytokous females in their pre-copulation, copulation duration and mating frequency. Productive gene transfer resulting from the mating between the two modes was experimentally confirmed. Gene transfer from arrhenotokous T. tabaci to thelytokous T. tabaci was further validated by confirmation of the passage of the arrhenotokous male-originated nuclear gene (histone H3 gene) allele to the F2 generation. These behavioral, ecological and genetic studies confirmed gene transfer from the sexual arrhenotokous mode to the asexual thelytokous mode of T. tabaci in the laboratory. These results demonstrate that asexual T. tabaci populations may acquire genetic variability from sexual populations, which could offset the long-term disadvantage of asexual reproduction. PMID:26375283

  19. Systemic effects of neem on western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae).

    PubMed

    Thoeming, G; Borgemeister, C; Sétamou, M; Poehling, H M

    2003-06-01

    The systemic effects of neem on the western flower thrips, Frankliniella occidentalis (Pergande), were investigated in laboratory trials using green bean, Phaseolus vulgaris L., in arena and microcosm experiments. In arena experiments, systemic effects of neem against western flower thrips larvae on primary bean leaves were observed with maximum corrected mortality of 50.6%. In microcosm experiments using bean seedlings, higher efficacy in the control of western flower thrips were observed with soil applications of neem on a substrate mixture (i.e., Fruhstorfer Erde, Type P, and sand) in a 1:1 ratio (93% corrected mortality) compared with application on the commercial substrate only (76% corrected mortality). However, longer persistence of neem was observed with soil application on the commercial substrate, which showed effects against thrips for up to 6 d after application. In addition to systemic effects observed on all foliage-feeding stages of western flower thrips, mortality on contact and repellent effects were observed on soil-inhabiting stages after soil applications of neem. Finally, bean seedlings grown from seeds pregerminated for 3 d in neem emulsion were also toxic to western flower thrips. PMID:12852622

  20. Detection of Gene Flow from Sexual to Asexual Lineages in Thrips tabaci (Thysanoptera: Thripidae)

    PubMed Central

    Li, Xiao-Wei; Wang, Ping; Fail, Jozsef; Shelton, Anthony M.

    2015-01-01

    Populations of Thrips tabaci are known to have two sympatric but genetically isolated reproductive modes, arrhenotoky (sexual reproduction) and thelytoky (asexual reproduction). Herein, we report behavioral, ecological and genetic studies to determine whether there is gene flow between arrhenotokous and thelytokous T. tabaci. We did not detect significant preference by arrhenotokous males to mate with females of a particular reproductive mode, nor did we detect significant behavioral differences between arrhenotokous males mated with arrhenotokous or thelytokous females in their pre-copulation, copulation duration and mating frequency. Productive gene transfer resulting from the mating between the two modes was experimentally confirmed. Gene transfer from arrhenotokous T. tabaci to thelytokous T. tabaci was further validated by confirmation of the passage of the arrhenotokous male-originated nuclear gene (histone H3 gene) allele to the F2 generation. These behavioral, ecological and genetic studies confirmed gene transfer from the sexual arrhenotokous mode to the asexual thelytokous mode of T. tabaci in the laboratory. These results demonstrate that asexual T. tabaci populations may acquire genetic variability from sexual populations, which could offset the long-term disadvantage of asexual reproduction. PMID:26375283

  1. Evolution of asexuality via different mechanisms in grass thrips (thysanoptera: Aptinothrips).

    PubMed

    van der Kooi, Casper J; Schwander, Tanja

    2014-07-01

    Asexual lineages can derive from sexual ancestors via different mechanisms and at variable rates, which affects the diversity of the asexual population and thereby its ecological success. We investigated the variation and evolution of reproductive systems in Aptinothrips, a genus of grass thrips comprising four species. Extensive population surveys and breeding experiments indicated sexual reproduction in A. elegans, asexuality in A. stylifer and A. karnyi, and both sexual and asexual lineages in A. rufus. Asexuality in A. stylifer and A. rufus coincides with a worldwide distribution, with sexual A. rufus lineages confined to a limited area. Inference of molecular phylogenies and antibiotic treatment revealed different causes of asexuality in different species. Asexuality in A. stylifer and A. karnyi has most likely genetic causes, while it is induced by endosymbionts in A. rufus. Endosymbiont-community characterization revealed presence of Wolbachia, and lack of other bacteria known to manipulate host reproduction. However, only 69% asexual A. rufus females are Wolbachia-infected, indicating that either an undescribed endosymbiont causes asexuality in this species or that Wolbachia was lost in several lineages that remained asexual. These results open new perspectives for studies on the maintenance of mixed sexual and asexual reproduction in natural populations.

  2. Australian thrips of the Haplothrips lineage (Insecta: Thysanoptera)

    SciTech Connect

    Mound, Laurence A.; Minaei, Kambiz

    2007-12-01

    Water is important and ubiquitous and surprisingly not understood. Just because is it common, does not mean its understood "Poets say science takes away from the beauty of the stars-mere globs of gas atoms. I too can see the stars on a desert night, and feel them. But do I see less or more? ... What is the pattern, or the meaning, or the why? It does not do harm to the mystery to know a little about it. For far more marvelous is the truth than any artists of the past imagined it." - Richard P. Feynman, The Feynman Lectures on Physics, 1963. (Cited in the introduction to Chapter 3 of "The Snowflake, Winter's Secret Beauty, Text by Kenneth Libbrecht, Photography by Patricia Rasmussen.) 1. Highlight the fact that water is still one of the most active and challenging research areas in chemistry and physics 2. Describe in general terms why water is unique from the point of view of its properties o Large dipole-moment o Very polarizable o Involved in is own chemistry (e.g. auto ionization defining the pH scale) • Atomic view: o Oxygen and Hydrogen. o Hydrogen is a quantum mechanical in nature. Classical physics is no good. o Water’s Charge-charge interaction described by classical physics laws (e.g. Coulomb) o The statistical mechanics of water. Why counting is important. o You need the full arsenal of theoretical methods to understand water • Waters well known bulk properties do not explain waters anomalies o Surface tension, heat capacity • Understanding the microscopic nature of water and how this gives rise to the known bulk quantities is the thrust of state-of-the-art research o Hydrogen bonding o Liquid structure o The so-called “spherical cow” model gets you no where with water o There are 10s-100s of different water models available in the scientific literature. It is a hard business • All of life takes place at the interfaces of solid, liquid, and gas o Biology takes advantage of waters varying properties in different geometries (e.g. confined, surfaces, etc. o Water behaves differently in confined environments • Water is the most abundant greenhouse gas o How does a microscopic understanding of water impact our knowledge of the radiation budget of the earth o How does a microscopic understanding of water impact our knowledge of weather.

  3. Detection of Gene Flow from Sexual to Asexual Lineages in Thrips tabaci (Thysanoptera: Thripidae).

    PubMed

    Li, Xiao-Wei; Wang, Ping; Fail, Jozsef; Shelton, Anthony M

    2015-01-01

    Populations of Thrips tabaci are known to have two sympatric but genetically isolated reproductive modes, arrhenotoky (sexual reproduction) and thelytoky (asexual reproduction). Herein, we report behavioral, ecological and genetic studies to determine whether there is gene flow between arrhenotokous and thelytokous T. tabaci. We did not detect significant preference by arrhenotokous males to mate with females of a particular reproductive mode, nor did we detect significant behavioral differences between arrhenotokous males mated with arrhenotokous or thelytokous females in their pre-copulation, copulation duration and mating frequency. Productive gene transfer resulting from the mating between the two modes was experimentally confirmed. Gene transfer from arrhenotokous T. tabaci to thelytokous T. tabaci was further validated by confirmation of the passage of the arrhenotokous male-originated nuclear gene (histone H3 gene) allele to the F2 generation. These behavioral, ecological and genetic studies confirmed gene transfer from the sexual arrhenotokous mode to the asexual thelytokous mode of T. tabaci in the laboratory. These results demonstrate that asexual T. tabaci populations may acquire genetic variability from sexual populations, which could offset the long-term disadvantage of asexual reproduction.

  4. The Scirtothrips perseae species-group (Thysanoptera), with one new species from avocado, Persea americana.

    PubMed

    Mound, Laurence A; Hoddle, Mark S

    2016-01-01

    Following recent molecular studies on avocado thrips, a new species is described from Costa Rica, Ecuador, and Colombia from the young leaves of avocado, Persea americana. Scirtothrips hansoni sp.n. is closely related to the Californian pest, S. perseae, and also to S. astrictus from Costa Rica that remains known from a single female. An illustrated key to these three species is provided. PMID:27396014

  5. Life History Characteristics of Frankliniella occidentalis and Frankliniella intonsa (Thysanoptera: Thripidae) in Constant and Fluctuating Temperatures.

    PubMed

    Ullah, Mohammad Shaef; Lim, Un Taek

    2015-06-01

    Frankliniella occidentalis (Pergande) and Frankliniella intonsa (Trybom) are sympatric pests of many greenhouse and field crops in Korea. We compared the influence of constant (27.3°C) and fluctuating temperatures (23.8-31.5°C, with an average of 27.3°C) on the life table characteristics of F. occidentalis and F. intonsa held at a photoperiod of 16:8 (L:D) h and 45±5% relative humidity. The development times of both F. occidentalis and F. intonsa were significantly affected by temperature fluctuation, species, and sex. The development time from egg to adult of F. intonsa was shorter than that for F. occidentalis at both constant and fluctuating temperatures. Survival of immature life stages was higher under fluctuating than constant temperature for both thrips species. The total and daily production of first instars was higher in F. intonsa (90.4 and 4.2 at constant temperature, and 95.7 and 3.9 at fluctuating temperatures) than that of F. occidentalis (58.7 and 3.3 at constant temperature, and 60.5 and 3.1 at fluctuating temperatures) under both constant and fluctuating temperatures. The percentage of female offspring was greater in F. intonsa (72.1-75.7%) than in F. occidentalis (57.4-58.7%) under both temperature regimes. The intrinsic rate of natural increase (rm) was higher at constant temperature than at fluctuating temperature for both thrips species. F. intonsa had a higher rm value (0.2146 and 0.2004) than did F. occidentalis (0.1808 and 0.1733), under both constant and fluctuating temperatures, respectively. The biological response of F. occidentalis and F. intonsa to constant and fluctuating temperature was found to be interspecifically different, and F. intonsa may have higher pest potential than F. occidentalis based on the life table parameters we are reporting first here.

  6. The Scirtothrips perseae species-group (Thysanoptera), with one new species from avocado, Persea americana.

    PubMed

    Mound, Laurence A; Hoddle, Mark S

    2016-02-12

    Following recent molecular studies on avocado thrips, a new species is described from Costa Rica, Ecuador, and Colombia from the young leaves of avocado, Persea americana. Scirtothrips hansoni sp.n. is closely related to the Californian pest, S. perseae, and also to S. astrictus from Costa Rica that remains known from a single female. An illustrated key to these three species is provided.

  7. Species of Thripinae (Thysanoptera) from bamboo in Malaysia, with one new species and six new records.

    PubMed

    Ng, Y F; Mound, L A

    2015-01-01

    Nine species of Thripinae that inhabit bamboo are recorded from Malaysia. Clypeothrips idrisi sp.n. is described as a second species in the genus, and Trichromothrips bruncurrum Reyes is considered a syn.n. of Neocorynothrips asiaticus Ramakrishna & Margabandhu. Six species are newly recorded from Malaysia: N. asiaticus, Okajimaella tubercula, Simulothrips banpoti, Stenchaetothrips bambusicola, S. bambusae and S. spinalis. Seven species of Stenchaetothrips are now known from Malaysia. Illustrations and descriptions of each species are provided.

  8. Influence of temperature on the development, reproduction and longevity of Ceratothripoides claratris (Thysanoptera: Thripidae) on tomatoes.

    PubMed

    Premachandra, W T S D; Borgemeister, C; Chabi-Olaye, A; Poehling, H-M

    2004-08-01

    Ceratothripoides claratris (Shumsher) is a serious pest attacking tomatoes in Thailand. Temperature-dependent development of C. claratris was studied at seven constant temperatures, i.e. 22, 25, 27, 30, 34, 35 and 40 degrees C. Pre-adult survivorship was greatest (95%) at 25 and 30 degrees C and shortest at 22 degrees C. Egg-to-adult time decreased within the range of 20 to 30 degrees C and at 34 degrees C it started to increase. The lower thermal threshold for egg-to-adult development was estimated at 16 and 18 degrees C by linear regression and the modified Logan model, respectively. The optimum temperature for egg-to-adult development was estimated at 32-33 degrees C by the modified Logan model. The influence of temperature on reproduction and longevity of C. claratris was determined at 25, 30 and 35 and 40 degrees C. Both inseminated and virgin females failed to reproduce at 40 degrees C. Virgin females produced only male offspring, confirming arrhenotoky. The sex ratio of the offspring of fertilized females was strongly female-biased, except at 25 degrees C. Mean total fecundity per female and mean daily total fecundity per female were highest for both virgin and inseminated females at 30 degrees C. Female longevity was longest at 25 degrees C and shortest at 40 degrees C. Male longevity was longest at 30 degrees C and shortest at 40 degrees C. The net reproductive rate (R0) and intrinsic rate of natural increase (rm) was greatest at 30 degrees C while, mean generation time (G) and the doubling time (t) were highest at 25 degrees C. The finite rate of increase (lambda) was fairly constant (1.1-1.5 days) over the three temperatures tested. The pest potential of C. claratris for tropical Asia is discussed.

  9. Minute pollinators: The role of thrips (Thysanoptera) as pollinators of pointleaf manzanita, Arctostaphylos pungens (Ericaceae)

    PubMed Central

    Eliyahu, Dorit; McCall, Andrew C.; Lauck, Marina; Trakhtenbrot, Ana; Bronstein, Judith L.

    2015-01-01

    The feeding habits of thrips on plant tissue, and their ability to transmit viral diseases to their host plants, have usually placed these insects in the general category of pests. However, the characteristics that make them economically important, their high abundance and short- and long-distance movement capability, may also make them effective pollinators. We investigated this lesser-known role of thrips in pointleaf manzanita (Arctostaphylos pungens), a Southwestern US shrub. We measured the abundance of three species of thrips (Orothrips kelloggii, Oligothrips oreios, and Frankliniella occidentalis), examined their pollen-carrying capability, and conducted an exclusion experiment in order to determine whether thrips are able to pollinate this species, and if they do, whether they actually contribute to the reproductive success of the plant. Our data suggest that indeed thrips pollinate and do contribute significantly to reproductive success. Flowers exposed to thrips only produced significantly more fruit than did flowers from which all visitors were excluded. The roles of thrips as antagonists/mutualists are examined in the context of the numerous other floral visitors to the plant. PMID:26207155

  10. Transmission of Iris yellow spot virus by Frankliniella fusca and Thrips tabaci (Thysanoptera: Thripidae).

    PubMed

    Srinivasan, Rajagopalbabu; Sundaraj, Sivamani; Pappu, Hanu R; Diffie, Stan; Riley, David G; Gitaitis, Ron D

    2012-02-01

    Thrips-transmitted Iris yellow spot virus (IYSV) (Family Bunyaviridae, Genus Tospovirus) affects onion production in the United States and worldwide. The presence of IYSV in Georgia was confirmed in 2003. Two important thrips species that transmit tospoviruses, the onion thrips (Thrips tabaci (Lindeman)) and the tobacco thrips (Frankliniella fusca (Hinds)) are known to infest onion in Georgia. However, T. tabaci is the only confirmed vector of IYSV. Experiments were conducted to test the vector status of F. fusca in comparison with T. tabaci. F. fusca and T. tabaci larvae and adults reared on IYSV-infected hosts were tested with antiserum specific to the nonstructural protein of IYSV through an antigen coated plate ELISA. The detection rates for F. fusca larvae and adults were 4.5 and 5.1%, respectively, and for T. tabaci larvae and adults they were 20.0 and 24.0%, respectively, indicating that both F. fusca and T. tabaci can transmit IYSV. Further, transmission efficiencies of F. fusca and T. tabaci were evaluated by using an indicator host, lisianthus (Eustoma russellianum (Salisbury)). Both F. fusca and T. tabaci transmitted IYSV at 18.3 and 76.6%, respectively. Results confirmed that F. fusca also can transmit IYSV but at a lower efficiency than T. tabaci. To attest if low vector competency of our laboratory-reared F. fusca population affected its IYSV transmission capability, a Tomato spotted wilt virus (Family Bunyaviridae, Genus Tospovirus) transmission experiment was conducted. F. fusca transmitted Tomato spotted wilt virus at a competent rate (90%) suggesting that the transmission efficiency of a competent thrips vector can widely vary between two closely related viruses.

  11. Infestation of Caliothrips phaseoli (Thysanoptera: Thripidae) on Bean Cultivars Grown in the Winter, Rainy, and Dry Seasons in Brazil.

    PubMed

    Boiça Júnior, Arlindo Leal; Costa, Eduardo Neves; De Souza, Bruno Henrique Sardinha; Da Silva, Anderson Gonçalves; Chiorato, Alisson Fernando

    2015-08-01

    The present study aimed to identify common bean (Phaseolus vulgaris L.) cultivars less susceptible to Caliothrips phaseoli (Hood) in different growing seasons, to evaluate whether climatic conditions influence plant resistance to C. phaseoli infestation, and to investigate the preferred plant part for insect feeding. Eighteen common bean cultivars were evaluated in the winter season, and 19 cultivars were assessed in the rainy and dry seasons, under field conditions in the municipality of Jaboticabal, state of São Paulo, Brazil. Infestation of C. phaseoli nymphs in the upper and lower parts of the beans plants was recorded at weekly intervals from 25 days after plant emergence (DAE) to 60 DAE. In the winter season, the cultivars 'IAC Galante,' 'IAC Centauro,' 'IAC Carioca Eté,' and 'IAC Formoso' had significantly lower number of thrips than the cultivar 'IAC Diplomata.' In the rainy season, the cultivars 'IAC Harmonia' and 'IPR Siriri' had the lowest thrips infestation, differing from the cultivars 'BRS Pontal' and 'IAC Una.' The bean cultivars were equally susceptible to C. phaseoli in the dry season. The results suggest that C. phaseoli nymphs prefer to infest leaves of the lower part of bean plants, like most generalist herbivorous insects. In the winter and dry seasons, the highest thrips infestation was observed at 60 DAE, while in the rainy season, it was recorded from 32 to 46 DAE. Overall, C. phaseoli infestation on bean cultivars was not influenced by either temperature, relative humidity, or rainfall.

  12. Occurrence in Japan of Frankliniella hemerocallis (Thysanoptera, Thripidae), with description of the larva and key to Frankliniella species from Japan.

    PubMed

    Masumoto, Masami; Okajima, Shuji

    2013-01-01

    The occurrence in Japan of the daylily thrips, Frankliniella hemerocallis, is confirmed. This thrips probably originated in Asia or Eurasia, because it is highly specific to Hemerocallis [Liliaceae] which is native to these areas. This thrips feeds on leaf, stem and petals rather than pollen. The second instar larva is described, and a key provided to the adults of Frankliniella species recorded from Japan. PMID:26258207

  13. New tropical fruit hosts of Scirtothrips dorsalis (Thysanoptera: Thripidae) and its relative abundance on them in South Florida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chilli thrips, Scritothrips dorsalis Hood, recently established in the southeast region of the United States, poses an economic threat to a wide-range of ornamental and vegetable plants. During scouting and sampling various hosts at different commercial nursery locations in Florida (Miami-Dade Count...

  14. Ambaeolothrips: a new genus of Neotropical Aeolothripidae (Thysanoptera), with observations on the type-species from mango trees in Mexico.

    PubMed

    Mound, Laurence; Cavalleri, Adriano; O'donnell, Cheryle; Infante, Francisco; Ortiz, Antonio; Goldarazena, Arturo

    2016-01-01

    Ambaeolothrips gen. n. is diagnosed for three Neotropical species: the type species romanruizi Ruiz-De la Cruz et al. comb. n. from Mexico, microstriatus Hood comb. n. from Panama, and pampeanus sp. n. from southern Brazil. Variation is discussed among character states that are used in the generic classification of the family Aeolothripidae, including segmentation of the antennae and maxillary palps, sculpture of the metanotum and presence of sternal discal setae. New field observations on the biology of romanruizi indicate that this species is phytophagous in flowers and on leaves, with no evidence of predation on the larvae of other thrips. PMID:27395682

  15. Evaluation and validation of reference genes for qRT-PCR normalization in Frankliniella occidentalis (Thysanoptera: Thripidae).

    PubMed

    Zheng, Yu-Tao; Li, Hong-Bo; Lu, Ming-Xing; Du, Yu-Zhou

    2014-01-01

    Quantitative real time PCR (qRT-PCR) has emerged as a reliable and reproducible technique for studying gene expression analysis. For accurate results, the normalization of data with reference genes is particularly essential. Once the transcriptome sequencing of Frankliniella occidentalis was completed, numerous unigenes were identified and annotated. Unfortunately, there are no studies on the stability of reference genes used in F. occidentalis. In this work, seven candidate reference genes, including actin, 18S rRNA, H3, tubulin, GAPDH, EF-1 and RPL32, were evaluated for their suitability as normalization genes under different experimental conditions using the statistical software programs BestKeeper, geNorm, Normfinder and the comparative ΔCt method. Because the rankings of the reference genes provided by each of the four programs were different, we chose a user-friendly web-based comprehensive tool RefFinder to get the final ranking. The result demonstrated that EF-1 and RPL32 displayed the most stable expression in different developmental stages; RPL32 and GAPDH showed the most stable expression at high temperatures, while 18S and EF-1 exhibited the most stable expression at low temperatures. In this study, we validated the suitable reference genes in F. occidentalis for gene expression profiling under different experimental conditions. The choice of internal standard is very important in the normalization of the target gene expression levels, thus validating and selecting the best genes will help improve the quality of gene expression data of F. occidentalis. What is more, these validated reference genes could serve as the basis for the selection of candidate reference genes in other insects.

  16. Insecticide Rotation Programs with Entomopathogenic Organisms for Suppression of Western Flower Thrips (Thysanoptera: Thripidae) Adult Populations under Greenhouse Conditions.

    PubMed

    Kivett, Jessica M; Cloyd, Raymond A; Bello, Nora M

    2015-08-01

    Western flower thrips, Frankliniella occidentalis (Pergande), is one of the most destructive insect pests of greenhouse production systems with the ability to develop resistance to a wide variety of insecticides. A common resistance management strategy is rotating insecticides with different modes of action. By incorporating entomopathogenic organisms (fungi and bacteria), which have discrete modes of action compared to standard insecticides, greenhouse producers may preserve the effectiveness of insecticides used for suppression of western flower thrips populations. The objective of this study was to determine how different rotation programs that include entomopathogenic organisms (Beauveria bassiana, Isaria fumosoroseus, Metarhizium anisopliae, and Chromobacterium subtsugae) and commonly used standard insecticides (spinosad, chlorfenapyr, abamectin, and pyridalyl) may impact the population dynamics of western flower thrips adult populations by means of suppression. Eight-week rotation programs were applied to chrysanthemum, Dendranthema x morifolium plants and weekly counts of western flower thrips adults captured on yellow sticky cards were recorded as a means to evaluate the impact of the rotation programs. A final quality assessment of damage caused by western flower thrips feeding on foliage and flowers was also recorded. Furthermore, a cost comparison of each rotation program was conducted. Overall, insecticide rotation programs that incorporated entomopathogenic organisms were not significantly different than the standard insecticide rotation programs without entomopathogenic organisms in suppressing western flower thrips adult populations. However, there were no significant differences among any of the rotation programs compared to the water control. Moreover, there was no differential effect of the rotation programs on foliage and flower quality. Cost savings of up to 34% (in US dollars) are possible when including entomopathogenic organisms in the rotation program. Therefore, by incorporating entomopathogenic organisms into insecticide rotation programs, greenhouse producers can decrease costs without affecting suppression, as well as diminish selection pressure on western flower thrips adult populations, which may avoid or delay resistance development. PMID:26470338

  17. Thrips tabaci (Thysanoptera: Thripidae) and Iris yellow spot virus associated with onion transplants, onion volunteers, and weeds in Colorado

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thrips tabaci infestation was determined on onion transplants received in Colorado during March and April from out of state sources (Imperial Valley, near Phoenix Arizona, and southern Texas) during 2004 to 2008. In the five years of the study, 50% to 100% of the transplant lots sampled were found ...

  18. A new record of Holarctic genus Odontothrips (Thysanoptera, Thripidae) from India with a new species.

    PubMed

    Tyagi, Kaomud; Kumar, Vikas

    2016-01-01

    The Holarctic genus Odontothrips of Megalurothrips genus-group was established by Amyot & Serville in 1843 with type species Thrips phaleratus Haliday (Mound & Palmer 1981, Mirab-balou & Chen 2011). This genus is known by 32 species from the Palearctic and Nearctic regions (ThripsWiki 2015), and these species are flower-living and mainly associated with flowers of family Fabaceae (Xie et al. 2010). The pest status of Odontothrips species is uncertain, but some species are reported to cause superficial damage to the flowers on which they feed. O. confusus Priesner is reported as a pest on lucerne in France and Czech Republic (Pitkin 1972), and also on legumes in Romania (Pustai et al. 2015). O. loti (Haliday) is reported as a major pest on Alfalfa in north China, where it feeds on tender leaves and causes leaf curling, whitening and withering (Kou et al. 2011). PMID:27395891

  19. Insecticide Rotation Programs with Entomopathogenic Organisms for Suppression of Western Flower Thrips (Thysanoptera: Thripidae) Adult Populations under Greenhouse Conditions.

    PubMed

    Kivett, Jessica M; Cloyd, Raymond A; Bello, Nora M

    2015-08-01

    Western flower thrips, Frankliniella occidentalis (Pergande), is one of the most destructive insect pests of greenhouse production systems with the ability to develop resistance to a wide variety of insecticides. A common resistance management strategy is rotating insecticides with different modes of action. By incorporating entomopathogenic organisms (fungi and bacteria), which have discrete modes of action compared to standard insecticides, greenhouse producers may preserve the effectiveness of insecticides used for suppression of western flower thrips populations. The objective of this study was to determine how different rotation programs that include entomopathogenic organisms (Beauveria bassiana, Isaria fumosoroseus, Metarhizium anisopliae, and Chromobacterium subtsugae) and commonly used standard insecticides (spinosad, chlorfenapyr, abamectin, and pyridalyl) may impact the population dynamics of western flower thrips adult populations by means of suppression. Eight-week rotation programs were applied to chrysanthemum, Dendranthema x morifolium plants and weekly counts of western flower thrips adults captured on yellow sticky cards were recorded as a means to evaluate the impact of the rotation programs. A final quality assessment of damage caused by western flower thrips feeding on foliage and flowers was also recorded. Furthermore, a cost comparison of each rotation program was conducted. Overall, insecticide rotation programs that incorporated entomopathogenic organisms were not significantly different than the standard insecticide rotation programs without entomopathogenic organisms in suppressing western flower thrips adult populations. However, there were no significant differences among any of the rotation programs compared to the water control. Moreover, there was no differential effect of the rotation programs on foliage and flower quality. Cost savings of up to 34% (in US dollars) are possible when including entomopathogenic organisms in the rotation program. Therefore, by incorporating entomopathogenic organisms into insecticide rotation programs, greenhouse producers can decrease costs without affecting suppression, as well as diminish selection pressure on western flower thrips adult populations, which may avoid or delay resistance development.

  20. A novel mitochondrial genome architecture in thrips (Insecta: Thysanoptera): extreme size asymmetry among chromosomes and possible recent control region duplication

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multi-partite mitochondrial genomes are very rare in animals but have been found previously in two insect orders with highly rearranged genomes, the Phthiraptera (parasitic lice), and the Psocoptera (booklice/barklice). We provide the first report of a multi-partite mitochondrial genome architecture...

  1. Effectiveness of different emulsifiers for neem oil against the western flower thrips (Thysanoptera, Thripidae) and the warehouse moth (Lepidoptera, Pyralidae).

    PubMed

    Schroer, S; Sermann, H; Reichmuth, C; Büttner, C

    2001-01-01

    The neem tree produces highly specified acting insecticides mainly in its seeds. By pressurizing or extracting the seeds an insecticide oil can be manufactured. For successful application emulsifiers are needed to render the oil soluble in water. The heavy oil has to be stable in emulsion, but on the other hand the surfactant should not reduce the ecological property of the neem oil. The emulsifiers Lutensol TO10, Emulan ELP, Rimulgan and Tween 80 and for comparison the formulation NeemAzal-T/S were tested in their emulsion stability, as well as in their insecticidal effects towards two different insect pests: The western flower thrips Frankliniella occidentalis and the ware house moth Ephestia elutella. The emulsifiers were applied purely, and in different contents mixed in neem oil. Data showed significant differences of mortality and development on the tested pests. Lutensol TO10 and Emulan ELP caused spontaneous mortality on the western flower thrips and an additive efficacy when mixed with neem oil. Rimulgan led to mortality of the larvae of the warehouse moth. NeemAzal showed in both bioassays the highest efficacy of 95% mortality. PMID:12425067

  2. The Old-World genus Ceratothripoides (Thysanoptera: Thripidae) with a new genus for related New-World species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A key is provided to five Old World species that comprise the genus Ceratothripoides Bagnall, and the species C. revelatus (Priesner) is recalled from synonymy with C. brunneus Bagnall. Five New World species previously placed in this genus are here allocated to Retanathrips Mound & Nickle gen.n., w...

  3. Bell and banana pepper exhibit mature-plant resistance to tomato spotted wilt Tospovirus transmitted by Frankliniella fusca (Thysanoptera: Thripidae).

    PubMed

    Beaudoin, A L P; Kahn, N D; Kennedy, G G

    2009-02-01

    Tomato spotted wilt virus (family Bunyaviridae, genus Tospovirus, TSWV) causes annual economic losses in pepper, Capsicum annuum L., across the southern United States and is transmitted by several species of thrips, including the tobacco thrips, Frankliniella fusca (Hinds). Reduced virus transmission and symptom severity as plant age increases is known as mature-plant resistance. TSWV transmission to pepper plants was examined in three and four age classes in field and greenhouse trials, respectively. In the field trial, 'Camelot' bell pepper plants were exposed to potentially viruliferous F. fusca 37, 51, or 65 d postsowing. Two greenhouse trials of Camelot bell and one trial each of 'Bounty' and 'Pageant' banana pepper plants were exposed to potentially viruliferous F. fusca, 43, 57, 71, or 85; 48, 62, 75, or 90; 42, 56, 70, or 84; and 43, 57, 71, or 85 d postsowing, respectively. Linear and hyperbolic regressions of percentage of infected plants per block on days postsowing indicated mature-plant resistance in all trials. All models were significant, but hyperbolic curves better fit the data than linear models. Hyperbolic models were used to calculate the number of days posttransplant at which a 50% decrease from the predicted percentage of infected plants at transplant age (42 d postsowing) was expected. This was referred to as days posttransplant-50 (DPT50). DPRT50 occurred within 9 days posttransplant age for all trials, indicating that early TSWV management in pepper is critical.

  4. Evaluation of a push-pull strategy for the management of Frankliniella bispinosa (Thysanoptera: Thripidae) in bell peppers.

    PubMed

    Tyler-Julian, Kara; Funderburk, Joe; Frantz, Galen; Mellinger, Charles

    2014-10-01

    A push-pull strategy for managing the anthophilous Frankliniella bispinosa (Morgan) in pepper and increasing conservation biological control was evaluated. Push components of ultraviolet (UV)-reflective mulch and foliar applications of kaolin and the pull component of sunflower companion plants were evaluated in replicated field experiments in 2011 and 2012. Adult F. bispinosa rapidly colonized and reproduced in the peppers and sunflowers during early flowering, but populations declined later, as numbers of the predatory Orius insidiosus (Say) and Orius pumilio (Champion) increased in both hosts. Numbers of F. bispinosa were reduced by kaolin during early pepper flowering. Thrips numbers were increased on some of the later sample dates, apparently due to reduced predation that resulted from negative effects of kaolin and UV-reflective mulch on Orius populations. Numbers of thrips increased in peppers with companion plants during the first week of flowering each year, followed by declines in thrips numbers during the next 2 wk in 2011. There was little effect each year of the companion plants on the numbers of Orius in the pepper flowers. There was one date in 2011 and no dates in 2012 in which UV-reflective mulch or kaolin acted in concert with the presence of the companion plants to reduce thrips numbers in the main crop of pepper. Yield effects were not attributed to thrips damage. We conclude that sunflower companion plants did not act additively or synergistically with kaolin or UV-reflective mulch to reduce thrips and increase Orius populations in pepper.

  5. The mitochondrial genome of Frankliniella intonsa: insights into the evolution of mitochondrial genomes at lower taxonomic levels in Thysanoptera.

    PubMed

    Yan, Dankan; Tang, Yunxia; Hu, Min; Liu, Fengquan; Zhang, Dongfang; Fan, Jiaqin

    2014-10-01

    Thrips is an ideal group for studying the evolution of mitochondrial (mt) genomes in the genus and family due to independent rearrangements within this order. The complete sequence of the mitochondrial DNA (mtDNA) of the flower thrips Frankliniella intonsa has been completed and annotated in this study. The circular genome is 15,215bp in length with an A+T content of 75.9% and contains the typical 37 genes and it has triplicate putative control regions. Nucleotide composition is A+T biased, and the majority of the protein-coding genes present opposite CG skew which is reflected by the nucleotide composition, codon and amino acid usage. Although the known thrips have massive gene rearrangements, it showed no reversal of strand asymmetry. Gene rearrangements have been found in the lower taxonomic levels of thrips. Three tRNA genes were translocated in the genus Frankliniella and eight tRNA genes in the family Thripidae. Although the gene arrangements of mt genomes of all three thrips species differ massively from the ancestral insect, they are all very similar to each other, indicating that there was a large rearrangement somewhere before the most recent common ancestor of these three species and very little genomic evolution or rearrangements after then. The extremely similar sequences among the CRs suggest that they are ongoing concerted evolution. Analyses of the up and downstream sequence of CRs reveal that the CR2 is actually the ancestral CR. The three CRs are in the same spot in each of the three thrips mt genomes which have the identical inverted genes. These characteristics might be obtained from the most recent common ancestor of this three thrips. Above observations suggest that the mt genomes of the three thrips keep a single massive rearrangement from the common ancestor and have low evolutionary rates among them.

  6. Evaluation of a push-pull strategy for the management of Frankliniella bispinosa (Thysanoptera: Thripidae) in bell peppers.

    PubMed

    Tyler-Julian, Kara; Funderburk, Joe; Frantz, Galen; Mellinger, Charles

    2014-10-01

    A push-pull strategy for managing the anthophilous Frankliniella bispinosa (Morgan) in pepper and increasing conservation biological control was evaluated. Push components of ultraviolet (UV)-reflective mulch and foliar applications of kaolin and the pull component of sunflower companion plants were evaluated in replicated field experiments in 2011 and 2012. Adult F. bispinosa rapidly colonized and reproduced in the peppers and sunflowers during early flowering, but populations declined later, as numbers of the predatory Orius insidiosus (Say) and Orius pumilio (Champion) increased in both hosts. Numbers of F. bispinosa were reduced by kaolin during early pepper flowering. Thrips numbers were increased on some of the later sample dates, apparently due to reduced predation that resulted from negative effects of kaolin and UV-reflective mulch on Orius populations. Numbers of thrips increased in peppers with companion plants during the first week of flowering each year, followed by declines in thrips numbers during the next 2 wk in 2011. There was little effect each year of the companion plants on the numbers of Orius in the pepper flowers. There was one date in 2011 and no dates in 2012 in which UV-reflective mulch or kaolin acted in concert with the presence of the companion plants to reduce thrips numbers in the main crop of pepper. Yield effects were not attributed to thrips damage. We conclude that sunflower companion plants did not act additively or synergistically with kaolin or UV-reflective mulch to reduce thrips and increase Orius populations in pepper. PMID:25199151

  7. A revision of the Axylus group of Agraeciini (Orthoptera: Tettigoniidae: Conocephalinae) and of some other species formerly included in Nicsara or Anthracites Revision of the Indo-Australian Conocephalinae, Part 3.

    PubMed

    Ingrisch, Sigfrid

    2015-01-01

    Axylus group is used to include the five genera Axylus Stål, 1877, Anthracites Redtenbacher, 1891 sensu stricto, Eucoptaspis Willemse, 1966, Eulobaspis gen. nov., and Heminicsara Karny, 1912. It is mainly based on a combination of the characters shape of pronotum, spiniform meso- and metasternal lobes, and similar basic ground plans of the male cerci, titillators and female subgenital plates. The five genera together with two superficially similar genera Euanthracites gen. nov. and Sulasara gen. nov. are fully revised. Papuacites gen. nov. is proposed for two New Guinean species formerly included in Anthracites. Nicsara Walker, 1869 is restricted to Australian species; Spinisternum Willemse, 1942 is synonymised with Heminicsara Karny, 1912; Odontocoryphus Karny, 1907 based on two nymphs is synonymised with Macroxiphus Pictet, 1888; Pseudoliara Karny, 1907 described after one nymph is regarded incertae sedis. 40 new combination of species are proposed: Axylus bimaculatus (Redtenbacher, 1891) comb. nov., A. inferior (Brunner, 1898) comb. nov., A. inflatus (Brunner, 1898) comb. nov., A. loboensis (De Haan, 1842) comb. nov., A. minutus (Dohrn, 1905) comb. nov., A. nigrifrons (Brunner, 1898) comb. nov., A. philippinus (Hebard, 1922) comb. nov., A, taylori (Hebard, 1922) comb. nov., and A. thoracicus (Dohrn, 1905) comb. nov. (all from Nicsara); Euanthracites apoensis (Hebard, 1922) comb. nov., E. femoralis (Dohrn, 1905) comb. nov., E. rufus (Ingrisch, 1998) comb. nov., and E. tibialis (Karny, 1931) comb. nov. (from Anthracites); Eucoptaspis inexpectatus (Willemse, 1953) comb. nov. (from Gonatacanthus Karny, 1907); Eulobaspis dehaani (Karny, 1920) comb. nov., E. emarginata (Karny, 1926) comb. nov., E. moluccana (Redtenbacher, 1891) comb. nov., E. personata (Karny, 1926) comb. nov., E. quadrimaculata (Karny, 1926) comb. nov., E. rotundata (Karny, 1926) comb. nov., and E. strigatipes (Bolivar, 1898) comb. nov. (from Nicsara); Eulobaspis lobaspoides (Karny, 1907) comb. nov

  8. Effects of Interplanting Flowering Plants on the Biological Control of Corn Earworm (Lepidoptera: Noctuidae) and Thrips (Thysanoptera: Thripidae) in Sweet Corn.

    PubMed

    Manandhar, Roshan; Wright, Mark G

    2016-02-01

    Natural enemy exploitation of food resources and alternative hosts in noncrop vegetation has been shown to be an effective means of enhancing natural enemy populations in diversified agro-ecosystem. Field trials were conducted in Hawaii to examine effects of interplanting flowering plants on 1) parasitism of corn earworm, Helicoverpa zea (Boddie) eggs by Trichogramma spp., and 2) abundance of Orius spp. in relation to prey (H. zea eggs and thrips [primarily, Frankliniella occidentalis (Pergande) and Frankliniella williamsi Hood]). Sweet corn (maize), Zea mays L., was interplanted with three flowering plants, buckwheat, Fagopyrum esculentum Moench, cowpea, Vigna unguiculata (L.), and sunn hemp, Crotolaria juncea L., at 2:1 and 4:1 (corn: flowering plant) ratios in 2009 and 2010, respectively. In 2009, the abundance of Orius spp. was significantly greater in the buckwheat-interplanted treatment compared to the monocrop control at similar levels of prey availability, indicating buckwheat flowers might have provided both prey and nectar resources. In 2010, cowpea and sunn hemp flowering plants provided a source of an alternate host insect's eggs for Trichogramma spp. oviposition, resulting in significantly higher parasitism of H. zea eggs in the cowpea- and sunn hemp-interplanted treatments compared to the monocrop control. Despite of differences in pest and natural enemy interactions in two field trials, our findings suggested that provisioning of an alternate host insect's eggs through flowering plants is an effective means for enhancing Trichogramma spp. and provisioning of both nectar and prey resources through flowering plants is important for enhancing predation by Orius spp. PMID:26500338

  9. Incidence and characterization of resistance to pyrethroid and organophosphorus insecticides in Thrips tabaci (Thysanoptera: Thripidae) in onion fields in Isfahan, Iran.

    PubMed

    Nazemi, A; Khajehali, J; Van Leeuwen, T

    2016-05-01

    Onion thrips, Thrips tabaci Lindeman, is the main pest of onion-growing fields in Isfahan and is mainly controlled by frequently spraying several insecticides. To investigate the resistance status and mechanisms, the susceptibility of ten field populations collected from Isfahan onion-growing regions were tested to several currently used pesticides. Resistance to the tested insecticides was observed in most populations when compared with the susceptible reference population. Enhanced detoxification, implicated by the use of inhibitors of major metabolic detoxification enzymes, was observed in the populations resistant to profenofos and chlorpyrifos. In the deltamethrin resistant populations, the amino acid substitution T929I was detected in the voltage gated sodium channel, which is known to confer pyrethroid resistance. These data are a first step towards more efficient resistance management tactics through early detection of resistant onion thrips in Iran. PMID:27017878

  10. Long-Distance Dispersal Potential for Onion Thrips (Thysanoptera: Thripidae) and Iris yellow spot virus (Bunyaviridae: Tospovirus) in an Onion Ecosystem.

    PubMed

    Smith, Erik A; Fuchs, M; Shields, E J; Nault, B A

    2015-08-01

    Onion thrips, Thrips tabaci Lindeman, is a worldwide pest of onion whose feeding damage and transmission of Iris yellow spot virus (IYSV) may reduce onion yields. Little is known about the seasonal dynamics of T. tabaci dispersal, the distance of dispersal, or the movement of thrips infected with IYSV during the onion-growing season. To address these questions, T. tabaci adults were collected using transparent sticky card traps in commercial onion fields three times during the onion-growing season (June, July, and late August) at varying heights above the canopy (0.5-6 m above soil surface) and with trap-equipped unmanned aircraft (UAVs) flying 50-60 m above onion fields during August sampling periods in 2012 and 2013. Randomly selected subsamples of captured T. tabaci were tested for IYSV using RT-PCR. Most T. tabaci adults were captured in late August and near the onion canopy (<2 m) throughout the season. However, 4% of T. tabaci adults captured on sticky cards were at altitudes ≥2 m, and T. tabaci were also captured on UAV-mounted traps. These data strongly suggest that long-distance dispersal occurs. More T. tabaci captured on sticky cards tested positive for IYSV in August (53.6%) than earlier in the season (2.3 to 21.5% in June and July, respectively), and 20 and 15% of T. tabaci captured on UAV-mounted traps tested positive for IYSV in 2012 and 2013, respectively. Our results indicate that T. tabaci adults, including viruliferous individuals, engage in long-distance dispersal late in the season and likely contribute to the spread of IYSV. PMID:26314037

  11. Genetic and host-associated differentiation within Thrips tabaci Lindeman (Thysanoptera: Thripidae) and its links to Tomato spotted wilt virus-vector competence.

    PubMed

    Westmore, G C; Poke, F S; Allen, G R; Wilson, C R

    2013-09-01

    Of eight thelytokous populations of onion thrips (Thrips tabaci) collected from potato (three populations), onion (four) or Chrysanthemum (one) hosts from various regions of Australia, only those from potato were capable of transmitting Tomato spotted wilt virus (TSWV) in controlled transmission experiments. Genetic differentiation of seven of these eight populations, and nine others not tested for TSWV vector competence, was examined by comparison of the DNA sequences of mitochondrial cytochrome oxidase subunit 1 (COI) gene. All Australian populations of T. tabaci grouped within the European 'L2' clade of Brunner et al. (2004). Within this clade the seven populations from potato, the three from onion, and the four from other hosts (Chrysanthemum, Impatiens, lucerne, blackberry nightshade) clustered as three distinct sub-groupings characterised by source host. Geographical source of thrips populations had no influence on genetic diversity. These results link genetic differentiation of thelytokous T. tabaci to source host and to TSWV vector capacity for the first time.

  12. Long-Distance Dispersal Potential for Onion Thrips (Thysanoptera: Thripidae) and Iris yellow spot virus (Bunyaviridae: Tospovirus) in an Onion Ecosystem.

    PubMed

    Smith, Erik A; Fuchs, M; Shields, E J; Nault, B A

    2015-08-01

    Onion thrips, Thrips tabaci Lindeman, is a worldwide pest of onion whose feeding damage and transmission of Iris yellow spot virus (IYSV) may reduce onion yields. Little is known about the seasonal dynamics of T. tabaci dispersal, the distance of dispersal, or the movement of thrips infected with IYSV during the onion-growing season. To address these questions, T. tabaci adults were collected using transparent sticky card traps in commercial onion fields three times during the onion-growing season (June, July, and late August) at varying heights above the canopy (0.5-6 m above soil surface) and with trap-equipped unmanned aircraft (UAVs) flying 50-60 m above onion fields during August sampling periods in 2012 and 2013. Randomly selected subsamples of captured T. tabaci were tested for IYSV using RT-PCR. Most T. tabaci adults were captured in late August and near the onion canopy (<2 m) throughout the season. However, 4% of T. tabaci adults captured on sticky cards were at altitudes ≥2 m, and T. tabaci were also captured on UAV-mounted traps. These data strongly suggest that long-distance dispersal occurs. More T. tabaci captured on sticky cards tested positive for IYSV in August (53.6%) than earlier in the season (2.3 to 21.5% in June and July, respectively), and 20 and 15% of T. tabaci captured on UAV-mounted traps tested positive for IYSV in 2012 and 2013, respectively. Our results indicate that T. tabaci adults, including viruliferous individuals, engage in long-distance dispersal late in the season and likely contribute to the spread of IYSV.

  13. Investigating the effect of invasion characteristics on onion thrips (Thysanoptera: Thripidae) populations in onions with a temperature-driven process model.

    PubMed

    Mo, Jianhua; Stevens, Mark; Liu, De Li; Herron, Grant

    2009-12-01

    A temperature-driven process model was developed to describe the seasonal patterns of populations of onion thrips, Thrips tabaci Lindeman, in onions. The model used daily cohorts (individuals of the same developmental stage and daily age) as the population unit. Stage transitions were modeled as a logistic function of accumulated degree-days to account for variability in development rate among individuals. Daily survival was modeled as a logistic function of daily mean temperature. Parameters for development, survival, and fecundity were estimated from published data. A single invasion event was used to initiate the population process, starting at 1-100 d after onion emergence (DAE) for 10-100 d at the daily rate of 0.001-0.9 adults/plant/d. The model was validated against five observed seasonal patterns of onion thrips populations from two unsprayed sites in the Riverina, New South Wales, Australia, during 2003-2006. Performance of the model was measured by a fit index based on the proportion of variations in observed data explained by the model (R (2)) and the differences in total thrips-days between observed and predicted populations. Satisfactory matching between simulated and observed seasonal patterns was obtained within the ranges of invasion parameters tested. Model best-fit was obtained at invasion starting dates of 6-98 DAE with a daily invasion rate of 0.002-0.2 adults/plant/d and an invasion duration of 30-100 d. Under the best-fit invasion scenarios, the model closely reproduced the observed seasonal patterns, explaining 73-95% of variability in adult and larval densities during population increase periods. The results showed that small invasions of adult thrips followed by a gradual population build-up of thrips within onion crops were sufficient to bring about the observed seasonal patterns of onion thrips populations in onion. Implications of the model on timing of chemical controls are discussed.

  14. Manipulation of Frankliniella occidentalis (Thysanoptera: Thripidae) by Tomato Spotted Wilt Virus (Tospovirus) Via the Host Plant Nutrients to Enhance Its Transmission and Spread

    PubMed Central

    Shalileh, Sheida; Moualeu, Dany Pascal; Poehling, Hans-Michael

    2016-01-01

    Earlier studies have shown that Tomato spotted wilt virus (TSWV) influences the biology, performance, and behavioral patterns of its vector Frankliniella occidentalis Pergande. In this study, using Capsicum annuum L. as the host plant, we aimed to determine the manipulation of F. occidentalis by TSWV through switching of the diet (+ or −TSWV) during vector’s development. Behavioral patterns, fitness, as well as vector performance were evaluated. The specific parameters investigated included longevity/survival, fecundity, development time, feeding, and preferential behavior. F. occidentalis were reared on either TSWV-infected (exposed) or healthy leaves (non-exposed) throughout their larval stages. The emerging adults were then individually transferred to either healthy or TSWV-infected leaf disks. This resulted into four treatments, consisting of exposed or non-exposed thrips reared on either infected or healthy leaf disks as adults. All F. occidentalis exposed to TSWV in their larval stages had shorter development time regardless of the adults’ diet. Whereas, the ones that were later reared on healthy leaf disks as adults recorded the highest longevity and reproduction rate. Furthermore, adults of F. occidentalis that were exposed to TSWV in their larval stages showed preference toward healthy leaf disks (−TSWV), whereas the non-exposed significantly preferred the infected leaf disks (+TSWV). These are further indications that TSWV modifies the nutritional content of its host plants, which influences vector’s biology and preferential behavior, in favor of its multiplication and dispersal. The findings offer additional explanation to the often aggressive spread of the virus in crop stands. PMID:27566527

  15. Low temperature phosphine fumigation of pre-chilled iceberg lettuce under insulation cover for postharvest control of western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fumigation of chilled iceberg lettuce under an insulation cover was studied to develop economical alternatives to conduct low temperature phosphine fumigation for control of western flower thrips, Frankliniella occidentalis (Pergande), on exported lettuce. Vacuum cooled commercial iceberg lettuce o...

  16. Low temperature–scanning electron microscopy to evaluate morphology and predation of Scolothrips sexmaculatus Pergande (Thysanoptera: Thripidae) against spider mites (Acari: Tetranychidae: Tetranychus species)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper evaluates the potential usefulness of low temperature-scanning electron microscopy (LT-SEM) to evaluate morphology and predation behavior of the six-spotted thrips (Scolothrips sexmaculatus Pergande) against the two-spotted spider mite (Tetranychus urticae (Koch)). Morphological features...

  17. Genetic and host-associated differentiation within Thrips tabaci Lindeman (Thysanoptera: Thripidae) and its links to Tomato spotted wilt virus-vector competence.

    PubMed

    Westmore, G C; Poke, F S; Allen, G R; Wilson, C R

    2013-09-01

    Of eight thelytokous populations of onion thrips (Thrips tabaci) collected from potato (three populations), onion (four) or Chrysanthemum (one) hosts from various regions of Australia, only those from potato were capable of transmitting Tomato spotted wilt virus (TSWV) in controlled transmission experiments. Genetic differentiation of seven of these eight populations, and nine others not tested for TSWV vector competence, was examined by comparison of the DNA sequences of mitochondrial cytochrome oxidase subunit 1 (COI) gene. All Australian populations of T. tabaci grouped within the European 'L2' clade of Brunner et al. (2004). Within this clade the seven populations from potato, the three from onion, and the four from other hosts (Chrysanthemum, Impatiens, lucerne, blackberry nightshade) clustered as three distinct sub-groupings characterised by source host. Geographical source of thrips populations had no influence on genetic diversity. These results link genetic differentiation of thelytokous T. tabaci to source host and to TSWV vector capacity for the first time. PMID:23632893

  18. Two years research on efficiency of two intercrops, birdsfoot trefoil and summer savory, to reduce damage caused by onion thrips(Thrips tabaci Lindeman, Thysanoptera, Thripidae) on leek.

    PubMed

    Gombac, P; Trdan, S

    2012-01-01

    In 2009 and 2011, a field experiment was carried out at the Laboratory Field at the Biotechnical Faculty in Ljubljana, Slovenia, with the aim to investigate suitability of two intercrops, birdsfoot trefoil (Lotus corniculatus L) and summer savory (Satureja hortensis L.), for reducing damage caused by onion thrips (Thrips tabaci Lindeman) on leek (Allium porrum L.). Four leek cultivars--'Columbus', 'Forrest', 'Lancelot' and 'Lincoln'--were used in the research (Bejo Zaden B.V., Netherlands). In both years, the mean index of damage caused by feeding of the pest on the leek leaves increased from the first evaluation (13 July 2009 and 18 June 2011) in both treatments with intercrops and in control treatment (without intercrop). Leek grown with birdsfoot trefoil as intercrop was in both years statistically the least damaged from thrips. Also summer savory was efficient in the same context in comparison with control treatment. In year 2009 cultivar 'Lancelot' was the least damaged in all treatments, and in year 2011 'Lancelot' and 'Forrest'. In both years intercrop and cultivar also had a significant influence on the yield of leek. The highest yield was obtained on the control plots, meanwhile birdsfoot trefoil and summer savory were pretty competitive and yield of leek grown with them as intercrops was therefore significantly lower.

  19. Post-Mating Interactions and Their Effects on Fitness of Female and Male Echinothrips americanus (Thysanoptera: Thripidae), a New Insect Pest in China

    PubMed Central

    Li, Xiao-Wei; Jiang, Hong-Xue; Zhang, Xiao-Chen; Shelton, Anthony M.; Feng, Ji-Nian

    2014-01-01

    Post-mating, sexual interactions of opposite sexes differ considerably in different organisms. Post-mating interactions such as re-mating behavior and male harassment can affect the fitness of both sexes. Echinothrips americanus is a new insect pest in Mainland China, and little is known about its post-mating interactions. In this study, we observed re-mating frequency and male harassment frequency and their effects on fitness parameters and offspring sex ratios of E. americanus females. Furthermore, we tested the impact of mating and post-mating interactions on fitness parameters of males. Our results revealed that the re-mating frequency in female adults was extremely low during a 30-day period. However, post-mating interactions between females and males, consisting mainly of male harassment and female resistance, did occur and significantly reduced female longevity and fecundity. Interestingly, increased access to males did not affect the ratio of female offspring. For males, mating dramatically reduced their longevity. However, post-mating interactions with females had no effects on the longevity of mated males. These results enrich our basic knowledge about female and male mating and post-mating behaviors in this species and provide important information about factors that may influence population regulation of this important pest species. PMID:24489956

  20. Potential of a strain of the entomopathogenic fungus Beauveria bassiana (Hypocreales: Cordycipitaceae) as a biological control agent against western flower thrips, Frankliniella occidentalis (Thysanoptera: Thripidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Five Beauveria bassiana strains were evaluated for control of western flower thrips. Strain RSB was the most virulent, causing 69-96% mortality at concentrations of 1×104 – 1×107 conidia mL-1, 10 days after inoculation of first instars. In greenhouse trials, RSB applied to broccoli foliage signifi...

  1. Evaluation of visual and olfactory cues for sampling three thrips species (Thysanoptera: Thripidae) in deciduous forests of the northern United States.

    PubMed

    Rieske, L K; Raffa, K F

    2003-06-01

    The introduced basswood thrips, Thrips calcaratus Uzel pear thrips, Taeniothrips inconsequens (Uzel), and native basswood thrips, Neohydatothrips tiliae (Hood), form a thrips complex that attacks buds and foliage of basswood, Tilia americana L., trees in the northern United States. We assessed the potential for exploiting visual and olfactory cues to monitor these forest thrips. We tested blue, green, red, white, and yellow for thrips' response to visual stimuli, and anisaldehyde, ethyl nicotinate, and polar and nonpolar extracts of basswood buds or leaves for thrips' response to olfactory stimuli over a 2-yr period. Generally, yellow traps tended to elicit the greatest visual response from all three species. None of the species showed significant attraction to the test volatiles compared with controls. The introduced basswood thrips, which is closely associated with expanding buds, was the most abundant species, and occurred earlier in the spring than the two flower- or foliage-associated species. The implications of these behaviors are discussed with respect to a forest pest monitoring program.

  2. Genetic and host-associated differentiation within Thrips tabaci Lindeman (Thysanoptera: Thripidae) and its links to Tomato spotted wilt virus-vector competence

    PubMed Central

    Westmore, G C; Poke, F S; Allen, G R; Wilson, C R

    2013-01-01

    Of eight thelytokous populations of onion thrips (Thrips tabaci) collected from potato (three populations), onion (four) or Chrysanthemum (one) hosts from various regions of Australia, only those from potato were capable of transmitting Tomato spotted wilt virus (TSWV) in controlled transmission experiments. Genetic differentiation of seven of these eight populations, and nine others not tested for TSWV vector competence, was examined by comparison of the DNA sequences of mitochondrial cytochrome oxidase subunit 1 (COI) gene. All Australian populations of T. tabaci grouped within the European ‘L2' clade of Brunner et al. (2004). Within this clade the seven populations from potato, the three from onion, and the four from other hosts (Chrysanthemum, Impatiens, lucerne, blackberry nightshade) clustered as three distinct sub-groupings characterised by source host. Geographical source of thrips populations had no influence on genetic diversity. These results link genetic differentiation of thelytokous T. tabaci to source host and to TSWV vector capacity for the first time. PMID:23632893

  3. The Liothrips-lineage of thrips (Thysanoptera: Phlaeothripidae) from Iran with the first record of micropterous morph of a Liothrips species.

    PubMed

    Minaei, Kambiz; Mound, Laurence

    2014-01-01

    A key is provided to the three Phlaeothripinae genera of the Liothrips-lineage known from Iran, Cephalothrips, Liothrips, and Liophloeothrips. Ataliothrips is placed as a new synonym of Liothrips, and the micropterous morph of L. reuteri described, this morph being unique among species of Liothrips. Illustrated keys are provided to the species of these genera recorded from Iran, all of which are considered to be leaf-feeding. In addition, a key is provided to the three species of Liophloeothrips from Europe, because L. hungaricus has been recorded from Iran although with no known voucher specimens.

  4. Commonly Intercepted Thrips at U.S. Ports-of-Entry from Africa, Europe, and the Mediterranean. IV. Miscellaneous thripine genera excluding Frankliniella, Iridothrips, and Thrips (Thysanoptera: Thripidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A total of 130 species of thrips occurring in Africa, Europe, and the Mediterranean region were intercepted by U. S. agricultural quarantine officers from shipments of plants and cut flowers at various ports-of-entry in the United States from 1983 to 1999. This paper is Part 4 of a guide to the iden...

  5. Winter weeds as inoculum sources of tomato spotted wilt virus and as reservoirs for its vector, Frankliniella fusca (Thysanoptera: Thripidae) in farmscapes of Georgia.

    PubMed

    Srinivasan, Rajagopalbabu; Riley, David; Diffie, Stan; Shrestha, Anita; Culbreath, Albert

    2014-04-01

    Thrips-transmitted Tomato spotted wilt virus (TSWV) has a broad host range including crops and weeds. In Georgia, TSWV is known to consistently affect peanut, tomato, pepper, and tobacco production. These crops are grown from March through November. In the crop-free period, weeds are presumed to serve as a green bridge for thrips and TSWV. Previous studies have identified several winter weeds as TSWV and thrips hosts. However, their ability to influence TSWV transmission in crops is still not completely understood. To further understand these interactions, population dynamics of two prevalent vectors, viz., Frankliniella fusca (Hinds) and Frankliniella occidentalis (Pergande), on selected winter weeds were monitored from October through April in four counties from 2004 to 2008. Peak populations were typically recorded in March. F. fusca and F. occidentalis adults were found on winter weeds and their percentages ranged from 0 to 68% in comparison with other adults. Immatures outnumbered all adults. Microcosm experiments indicated that the selected winter weeds differentially supported F. fusca reproduction and development. The time required to complete one generation (adult to adult) ranged from 11 to 16 d. Adult recovery ranged from 0.97 to 2.2 per female released. In addition, transmission assays revealed that thrips efficiently transmitted TSWV from peanut to weeds, the incidence of infection ranged from 10 to 55%. Back transmission assays with thrips from TSWV-infected weeds resulted in up to 75% TSWV infection in peanut. These whole-plant transmission and back transmission assays provide the basis for TSWV persistence in farmscapes year round.

  6. Regional and temporal variation in susceptibility to lambda-cyhalothrin in onion thrips, Thrips tabaci (Thysanoptera: Thripidae), in onion fields in New York.

    PubMed

    Shelton, A M; Nault, B A; Plate, J; Zhao, J Z

    2003-12-01

    Populations of onion thrips, Thrips tabaci Lindeman, from commercial onion fields in New York were evaluated for their susceptibility to the commonly used pyrethroid, lambda-cyhalothrin (Warrior T), using a novel system called the Thrips Insecticide Bioassay System (TIBS). To use TIBS, thrips are collected directly from the plant into an insecticide-treated 0.5-ml microcentrifuge tube that has a flexible plastic cap with a small well into which 0.08 ml of a 10% sugar-water solution with food colorant is deposited. The solution is sealed into the well with a small piece of stretched parafilm through which the thrips can feed on the solution. Thrips mortality is assessed after 24 h with the help of a dissecting stereoscope. In 2001, onion thrips populations were collected from 16 different sites and resistance ratios were >1,000 in five populations. Percent mortality at 100 ppm, a recommended field rate, varied from 9 to 100%, indicating high levels of variation in susceptibility. Particular instances of resistance appeared to be the result of practices within an individual field rather than a regional phenomenon. In 2002, we also observed large differences in onion thrips susceptibility, not only between individual fields but also between thrips collected in a single field at mid season and late season, again suggesting that insecticide-use practices within an individual field caused differences in susceptibility. Additional tests indicated no differences in susceptibility between adult and larval onion thrips populations and only relatively minor differences between populations collected from different parts of the same field. Using TIBS, several populations of onion thrips with different susceptibilities to lambda-cyhalothrin were identified and then subjected to lambda-cyhalothrin-treated onion plants. There was a highly significant positive relationship between percent mortality of thrips from TIBS and percent mortality from the treated onion plants, indicating that results from TIBS could be used to predict spray performance. These data suggest that use of TIBS for evaluating susceptibility to particular insecticides could be instrumental for developing a resistance management strategy for onion thrips. PMID:14977125

  7. Investigating the effect of invasion characteristics on onion thrips (Thysanoptera: Thripidae) populations in onions with a temperature-driven process model.

    PubMed

    Mo, Jianhua; Stevens, Mark; Liu, De Li; Herron, Grant

    2009-12-01

    A temperature-driven process model was developed to describe the seasonal patterns of populations of onion thrips, Thrips tabaci Lindeman, in onions. The model used daily cohorts (individuals of the same developmental stage and daily age) as the population unit. Stage transitions were modeled as a logistic function of accumulated degree-days to account for variability in development rate among individuals. Daily survival was modeled as a logistic function of daily mean temperature. Parameters for development, survival, and fecundity were estimated from published data. A single invasion event was used to initiate the population process, starting at 1-100 d after onion emergence (DAE) for 10-100 d at the daily rate of 0.001-0.9 adults/plant/d. The model was validated against five observed seasonal patterns of onion thrips populations from two unsprayed sites in the Riverina, New South Wales, Australia, during 2003-2006. Performance of the model was measured by a fit index based on the proportion of variations in observed data explained by the model (R (2)) and the differences in total thrips-days between observed and predicted populations. Satisfactory matching between simulated and observed seasonal patterns was obtained within the ranges of invasion parameters tested. Model best-fit was obtained at invasion starting dates of 6-98 DAE with a daily invasion rate of 0.002-0.2 adults/plant/d and an invasion duration of 30-100 d. Under the best-fit invasion scenarios, the model closely reproduced the observed seasonal patterns, explaining 73-95% of variability in adult and larval densities during population increase periods. The results showed that small invasions of adult thrips followed by a gradual population build-up of thrips within onion crops were sufficient to bring about the observed seasonal patterns of onion thrips populations in onion. Implications of the model on timing of chemical controls are discussed. PMID:20021751

  8. Manipulation of Frankliniella occidentalis (Thysanoptera: Thripidae) by Tomato Spotted Wilt Virus (Tospovirus) Via the Host Plant Nutrients to Enhance Its Transmission and Spread

    PubMed Central

    Shalileh, Sheida; Moualeu, Dany Pascal; Poehling, Hans-Michael

    2016-01-01

    Earlier studies have shown that Tomato spotted wilt virus (TSWV) influences the biology, performance, and behavioral patterns of its vector Frankliniella occidentalis Pergande. In this study, using Capsicum annuum L. as the host plant, we aimed to determine the manipulation of F. occidentalis by TSWV through switching of the diet (+ or −TSWV) during vector’s development. Behavioral patterns, fitness, as well as vector performance were evaluated. The specific parameters investigated included longevity/survival, fecundity, development time, feeding, and preferential behavior. F. occidentalis were reared on either TSWV-infected (exposed) or healthy leaves (non-exposed) throughout their larval stages. The emerging adults were then individually transferred to either healthy or TSWV-infected leaf disks. This resulted into four treatments, consisting of exposed or non-exposed thrips reared on either infected or healthy leaf disks as adults. All F. occidentalis exposed to TSWV in their larval stages had shorter development time regardless of the adults’ diet. Whereas, the ones that were later reared on healthy leaf disks as adults recorded the highest longevity and reproduction rate. Furthermore, adults of F. occidentalis that were exposed to TSWV in their larval stages showed preference toward healthy leaf disks (−TSWV), whereas the non-exposed significantly preferred the infected leaf disks (+TSWV). These are further indications that TSWV modifies the nutritional content of its host plants, which influences vector’s biology and preferential behavior, in favor of its multiplication and dispersal. The findings offer additional explanation to the often aggressive spread of the virus in crop stands.

  9. Potential use of the fungus Beauveria bassiana against the western flower thrips Frankliniella occidentalis without reducing the effectiveness of its natural predator Orius sauteri (Hemiptera: Anthocoridae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important predator of western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Orius sauteri would be directly exposed to the entomopathogenic fungus Beauveria bassiana (Bals.) Vuillemin in the field should the fu...

  10. Analyzing predation of hoverflies (Diptera: Syrphidae) in Mediterranean lettuce crops using molecular techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hoverflies are generalist predators of a great variety of primary pests. Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) and Frankliniella occidentalis (Thysanoptera: Thripidae) are two common pests in Mediterranean lettuce crops, where they occur alongside alternative prey (e.g., Collembola). ...

  11. Zorotypus weiweii (Zoraptera: Zorotypidae), a new species of angel insects, from Sabah, East Malaysia.

    PubMed

    Wang, Jianyun; Li, Hu; Cai, Wanzhi

    2016-01-01

    A new species of the insect order Zoraptera, Zorotypus weiweii, is described and figured from Sabah, East Malaysia. The new species represents the second angel insect from Borneo. Z. caudelli Karny was also collected near the type locality of Z. weiweii. Methods of specimen collection and a brief note of angel insects in Malaysia were provided based on new materials and biological observations. PMID:27615990

  12. Characteristic time-stepping or local preconditioning of the Euler equations

    NASA Technical Reports Server (NTRS)

    Van Leer, Bram; Lee, Wen-Tzong; Roe, Philip L.

    1991-01-01

    A derivation is presented of a local preconditioning matrix for multidimensional Euler equations, that reduces the spread of the characteristic speeds to the lowest attainable value. Numerical experiments with this preconditioning matrix are applied to an explicit upwind discretization of the two-dimensional Euler equations, showing that this matrix significantly increases the rate of convergence to a steady solution. It is predicted that local preconditioning will also simplify convergence-acceleration boundary procedures such as the Karni (1991) procedure for the far field and the Mazaheri and Roe (1991) procedure for a solid wall.

  13. Migration arising from gradients in shear stress: Particle distributions in Poiseuille flow

    NASA Technical Reports Server (NTRS)

    Leighton, D. T., Jr.

    1988-01-01

    Experimental evidence for the existence of shear induced migration processes is reviewed and the mechanism by Leighton and Acrivos (1987b) is described in detail. The proposed mechanism is shown to lead to the existence of an additional shear induced migration in the presence of gradients in shear stress such as would be found in Poiseuille flow, and which may be used to predict the amplitude of the observed short-term viscosity increase. The concentration and velocity profiles which result from such a migration are discussed in detail and are compared to the experimental observations of Karnis, Goldsmith and Mason (1966).

  14. Multiple origins of parasitism in lice: phylogenetic analysis of SSU rDNA indicates that the Phthiraptera and Psocoptera are not monophyletic.

    PubMed

    Murrell, Anna; Barker, Stephen C

    2005-10-01

    The Paraneoptera (Hemipteroid Assemblage) comprises the orders Thysanoptera (thrips), Hemiptera (bugs), Phthiraptera (lice) and Psocoptera (booklice and barklice). The phylogenetic relationships among the Psocodea (Phthiraptera and Psocoptera), Thysanoptera and Hemiptera are unresolved, as are some relationships within the Psocodea. Here, we present phylogenetic hypotheses inferred from SSU rDNA sequences; the most controversial of which is the apparent paraphyly of the Phthiraptera, which are parasites of birds and mammals, with respect to one family of Psocoptera, the Liposcelididae. The order Psocoptera and the suborder that contains the Liposcelididae, the Troctomorpha, are also paraphyletic. The two remaining psocopteran suborders, the Psocomorpha and the Trogiomorpha, are apparently monophyletic. The Liposcelididae is most closely related to lice from the suborder Amblycera. These results suggest that the taxonomy of the Psocodea needs revision. In addition, there are implications for the evolution of parasitism in insects; parasitism may have evolved twice in lice or have evolved once and been subsequently lost in the Liposcelididae.

  15. Application of cytochrome oxidase I sequences for phylogenetic analysis and identification of thrips species occurring on vegetable crops.

    PubMed

    Kadirvel, P; Srinivasan, R; Hsu, Yun-Che; Su, Fu-Cheng; De La Peña, R

    2013-02-01

    Thrips are direct pests as well as vectors of important viruses infecting crop plants. One of the major constraints in studying the relationship between thrips vectors and tospoviruses is the difficulty of identifying the vector species because of high intraspecific variation among thrips populations. Molecular approaches have been used to identify species differences. In this study, partial cytochrome oxidase I (COI) sequences were used to understand the phylogenetic relationship among thrips populations, and assess their usefulness to identify and classify unknown thrips species collected from different crops. In total, 29 COI variants were obtained while examining the sequence polymorphisms in COI of 182 insects analyzed in this study, which were collected from six countries on tomato, chilli, onion, cabbage, cucumber, watermelon, Ethiopian mustard, French bean, and peanut. The phylogenetic analysis showed that the insects used in this study clustered with five distinct species-groups designated as Thrips palmi group, T. tabaci group, Frankliniella occidentalis group, Scirtothrips dorsalis group and an unclassified group. Higher intraspecific genetic variation was observed in S. dorsalis and T. palmi followed by T. tabaci and F. occidentalis. Thus, it was confirmed that the COI gene could be useful in grouping different thrips species and genera that coexist in a particular cropping system. PMID:23448058

  16. Assessing the effects of cultivating genetically modified glyphosate-tolerant varieties of soybeans (Glycine max (L.) Merr.) on populations of field arthropods.

    PubMed

    Imura, Osamu; Shi, Kun; Iimura, Keiji; Takamizo, Tadashi

    2010-01-01

    We assessed the effects of cultivating two genetically modified (GM) glyphosate-tolerant soybean varieties (Glycine max (L.) Merr.) derived from Event 40-3-2 and a Japanese conventional variety on arthropods under field conditions, with weed control using glyphosate and conventional weed control for two years. Plant height and dry weight of the conventional variety were significantly larger than those of the GM varieties, but the GM varieties bore more pods than the conventional variety. We found arthropods of nine taxonomic orders (Araneae, Acari, Thysanoptera, Homoptera, Heteroptera, Coleoptera, Diptera, Lepidoptera, and Hymenoptera) on the plants. The arthropod incidence (number per plant unit weight pooled for each taxonomic order) on the soybean stems and leaves generally did not differ significantly between the GM and conventional varieties. However, the incidence of Thysanoptera and total incidence (all orders combined) were greater on the GM variety in the second year. The weed control regimes had no significant influence on the arthropod incidence on the soybean stems and leaves. The number of flower-inhabiting Thysanoptera (the dominant arthropod in the flowers) was not significantly different between the GM and conventional varieties. Asphondylia yushimai (Diptera, Cecidomyiidae) was more numerous on the pods of the GM variety in both years. Neither the soybean variety nor the weed control regime significantly affected the density of soil macro-organisms. However, the glyphosate weed control affected arthropods between the rows of plants by decreasing the abundances of Homoptera, Heteroptera, Coleoptera and Lepidoptera, and diversity of arthropods.

  17. Higher-level phylogeny of paraneopteran insects inferred from mitochondrial genome sequences

    PubMed Central

    Li, Hu; Shao, Renfu; Song, Nan; Song, Fan; Jiang, Pei; Li, Zhihong; Cai, Wanzhi

    2015-01-01

    Mitochondrial (mt) genome data have been proven to be informative for animal phylogenetic studies but may also suffer from systematic errors, due to the effects of accelerated substitution rate and compositional heterogeneity. We analyzed the mt genomes of 25 insect species from the four paraneopteran orders, aiming to better understand how accelerated substitution rate and compositional heterogeneity affect the inferences of the higher-level phylogeny of this diverse group of hemimetabolous insects. We found substantial heterogeneity in base composition and contrasting rates in nucleotide substitution among these paraneopteran insects, which complicate the inference of higher-level phylogeny. The phylogenies inferred with concatenated sequences of mt genes using maximum likelihood and Bayesian methods and homogeneous models failed to recover Psocodea and Hemiptera as monophyletic groups but grouped, instead, the taxa that had accelerated substitution rates together, including Sternorrhyncha (a suborder of Hemiptera), Thysanoptera, Phthiraptera and Liposcelididae (a family of Psocoptera). Bayesian inference with nucleotide sequences and heterogeneous models (CAT and CAT + GTR), however, recovered Psocodea, Thysanoptera and Hemiptera each as a monophyletic group. Within Psocodea, Liposcelididae is more closely related to Phthiraptera than to other species of Psocoptera. Furthermore, Thysanoptera was recovered as the sister group to Hemiptera. PMID:25704094

  18. Higher-level phylogeny of paraneopteran insects inferred from mitochondrial genome sequences.

    PubMed

    Li, Hu; Shao, Renfu; Song, Nan; Song, Fan; Jiang, Pei; Li, Zhihong; Cai, Wanzhi

    2015-02-23

    Mitochondrial (mt) genome data have been proven to be informative for animal phylogenetic studies but may also suffer from systematic errors, due to the effects of accelerated substitution rate and compositional heterogeneity. We analyzed the mt genomes of 25 insect species from the four paraneopteran orders, aiming to better understand how accelerated substitution rate and compositional heterogeneity affect the inferences of the higher-level phylogeny of this diverse group of hemimetabolous insects. We found substantial heterogeneity in base composition and contrasting rates in nucleotide substitution among these paraneopteran insects, which complicate the inference of higher-level phylogeny. The phylogenies inferred with concatenated sequences of mt genes using maximum likelihood and Bayesian methods and homogeneous models failed to recover Psocodea and Hemiptera as monophyletic groups but grouped, instead, the taxa that had accelerated substitution rates together, including Sternorrhyncha (a suborder of Hemiptera), Thysanoptera, Phthiraptera and Liposcelididae (a family of Psocoptera). Bayesian inference with nucleotide sequences and heterogeneous models (CAT and CAT + GTR), however, recovered Psocodea, Thysanoptera and Hemiptera each as a monophyletic group. Within Psocodea, Liposcelididae is more closely related to Phthiraptera than to other species of Psocoptera. Furthermore, Thysanoptera was recovered as the sister group to Hemiptera.

  19. Impact of factitious foods and prey on the oviposition of the predatory mites Gaeolaelaps aculeifer and Stratiolaelaps scimitus (Acari: Laelapidae).

    PubMed

    Navarro-Campos, C; Wäckers, F L; Pekas, A

    2016-09-01

    The soil-dwelling predatory mites Gaeolaelaps aculeifer and Stratiolaelaps scimitus (Mesostigmata: Laelapidae) are important biocontrol agents of several pests (Astigmata, Thysanoptera, Diptera). There is little information regarding the use of factitious foods that potentially improve their mass rearing and population development once released in the field. Here we tested the suitability of several types of factitious food and prey for G. aculeifer and S. scimitus. Factitious foods included eggs of Ephestia kuehniella (Lepidoptera: Pyralidae), hydrated encapsulated cysts of the brine shrimp Artemia sp. (Anostraca: Artemiidae), two species of saprophytic nematodes (Panagrellus redivivus and Panagrellus sp.) (Nematoda: Panagrolaimidae) and pollen of cattail Typha angustifolia (Poales: Typhaceae). Parameters tested were oviposition over a 3-day period compared with controls provided with either second instars of the thrips Frankliniella occidentalis (Thysanoptera: Thripidae) or a mix of instars of the commercially used prey mite Tyrophagus putrescentiae (Astigmatina: Acaridae) or the absence of food. Compared to the standard prey mite T. putrescentiae, G. aculeifer showed elevated oviposition when fed thrips larvae, E. kuehniella eggs, Artemia sp. cysts or the saprophytic P. redivivus. Oviposition by S. scimitus was high when provided with thrips larvae and P. redivivus, but not significantly different from oviposition on T. putrescentiae. Oviposition for both predatory mite species was very low or zero when provided with T. angustifolia pollen. Finally, G. aculeifer consumed significantly more thrips larvae than S. scimitus. The implication of these results for the mass-rearing of G. aculeifer and S. scimitus are discussed. PMID:27388446

  20. Embryonic development of Zoraptera with special reference to external morphology, and its phylogenetic implications (Insecta).

    PubMed

    Mashimo, Yuta; Beutel, Rolf G; Dallai, Romano; Lee, Chow-Yang; Machida, Ryuichiro

    2014-03-01

    The embryonic development of Zorotypus caudelli Karny (Zoraptera) is described with the main focus on its external features. A small heart-shaped embryo is formed on the dorsal side of the egg by the fusion of paired blastoderm regions with higher cellular density. The orientation of its anteroposterior axis is opposed to that of the egg. This unusual condition shows the potential autapomorphy of Zoraptera. The embryo extends along the egg surface and after reaching its full length, it migrates into the yolk. After developing there for a period of time, it reappears on the surface, accompanied by a reversion of its anteroposterior axis, finally taking its position on the ventral side of the egg. The definitive dorsal closure completes, and the prelarva hatches after perforating the chorion with very long egg tooth formed on the embryonic cuticle. Embryological data suggest the placement of Zoraptera among the "lower neopteran" or polyneopteran lineage: features supporting this are embryo formation by the fusion of paired regions with higher cellular density and blastokinesis accompanied by full elongation of the embryo on the egg surface. The extraordinarily long egg tooth has potential synapomorphy with Embioptera or Eukinolabia (= Embioptera + Phasmatodea). Together with the results from our previous studies on the egg structure, male reproductive system and spermatozoa, the close affinity of Zoraptera with Eukinolabia appears likely, that is, a clade Zoraptera + (Embioptera + Phasmatodea).

  1. Annotated list of Ensifera (Orthoptera) and further records on Caelifera (Orthoptera) of Mt Kilimanjaro, Tanzania.

    PubMed

    Hemp, Claudia

    2013-02-12

    A list of the Tettigoniidae and Gryllacrididae (Orthoptera: Ensifera) of Mt Kilimanjaro is presented. A total number of 63 Ensifera was recorded for this mountain, of which 25 species belonged to Phaneropterinae, 18 to Conocephalinae, 6 to Hetrodinae and three to Pseudophyllinae. The subfamily Meconematinae contributed two species while only one species of the subfamilies Hexacentrinae, Mecopodinae and Saginae was found. Gryllacrididae contributed six species. Three species recorded in literature were not found again during the research period. 15 species are newly recorded for Mt Kilimanjaro in this study and one species of Agraeciini newly described. Two new genera, Afroanthracites Hemp & Ingrisch n. gen. (type species: Anthracites montium Sjöstedt, 1910) and Afroagraecia Ingrisch & Hemp n. gen. (type species: Agraecia sansibara Redtenbacher, 1891), are erected on African Agraeciini (Conocephalinae). Anthracites kilimandjaricus Sjöstedt, 1910 is snonymized with A. montium Sjöstedt, 1910. Agraecia sansibara (Redtenbacher, 1891), Anthracites bloyeti Brongniart, 1897 and Anelytra panteli Karny are transferred to Afroagraecia. Aethiomerus stenorhinus Saussure, 1899 is synonymised with Afroagraecia sansibara (Redtenbacher, 1891). In Caelifera two Catantopinae (Acrididae) species are newly recorded for Mt Kilimanjaro and one pyrgomorphid species, Maura lurida (Fabricius, 1781), recovered again for the area.

  2. When hymenopteran males reinvented diploidy.

    PubMed

    Aron, Serge; de Menten, Ludivine; Van Bockstaele, Dirk R; Blank, Stephan M; Roisin, Yves

    2005-05-10

    In most plants and animals, a consistent relationship exists between the DNA content of a cell and its metabolic activity. The male-haploid sex determination of Hymenoptera and other arthropods may therefore impose a particular selective pressure upon males, which must evolve adaptations to cope with a genomic DNA reduced by half compared with that of females. Here, we show that a nuclear DNA content similar to that of females is restored in muscles of males in all hymenopteran lineages tested except the most basal one (Xyelidae). This doubling of DNA content in males does not occur in other haplodiploid insects, such as thrips (Thysanoptera) and whiteflies (Sternorrhyncha). These results indicate that this adaptation probably occurred early in hymenopteran history, possibly because males acquired strong flying and dispersal abilities.

  3. Insect galls from Serra de São José (Tiradentes, MG, Brazil).

    PubMed

    Maia, V C; Fernandes, G W

    2004-08-01

    One hundred thirty-seven morphotypes of insect galls were found on 73 plant species (47 genera and 30 families) in Serra de São José, in Tiradentes, MG, Brazil. Fabaceae, Myrtaceae, Asteraceae, and Melastomataceae were the plant families that supported most of the galls (49.6% of the total). Galls were mostly found on leaves and stems (66.4% and 25.5%, respectively). Galls were induced by Diptera, Lepidoptera, Coleoptera, Hemiptera (Sternorrhyncha), Hymenoptera, and Thysanoptera. The majority of them (73.7%) were induced by gall midges (Cecidomyiidae: Diptera). Besides the gall inducers, other insects found associated with the galls were parasitoids (Hymenoptera), inquilines (Coleoptera, Lepidoptera, Diptera, and Hemiptera), and predators (Diptera).

  4. Elevated air temperature alters an old-field insect community in a multi-factor climate change experiment

    SciTech Connect

    Villalpando, Sean; Williams, Ray; Norby, Richard J

    2009-01-01

    To address how multiple, interacting climate drivers may affect plant-insect community associations, we sampled the insect community from a constructed old-field plant community grown under simultaneous [CO2], temperature, and water manipulation. Insects were identified to morphospecies, assigned to feeding guilds and abundance, richness and evenness quantified. Warming significantly increased Order Thysanoptera abundance and reduced overall morphospecies richness and evenness. Non-metric multidimensional scaling clearly supported the effect of warming on insect community composition. Reductions in richness for herbivores and parasitoids suggest trophic-level effects within the insect community. Analysis of dominant insects demonstrated the effects of warming were limited to a relatively small number of morphospecies. Reported reductions in whole-community foliar N at elevated [CO2] unexpectedly did not result in any effects on herbivores. These results demonstrate climatic warming may alter certain insect communities via effects on insect species most responsive to higher temperature, contributing to a change in community structure.

  5. Thrips transmission of tospoviruses.

    PubMed

    Rotenberg, Dorith; Jacobson, Alana L; Schneweis, Derek J; Whitfield, Anna E

    2015-12-01

    One hundred years ago, the disease tomato spotted wilt was first described in Australia. Since that time, knowledge of this disease caused by Tomato spotted wilt virus (TSWV) and transmitted by thrips (insects in the order Thysanoptera) has revealed a complex relationship between the virus, vector, plant host, and environment. Numerous tospoviruses and thrips vectors have been described, revealing diversity in plant host range and geographical distributions. Advances in characterization of the tripartite interaction between the virus, vector, and plant host have provided insight into molecular and ecological relationships. Comparison to animal-infecting viruses in the family Bunyaviridae has enabled the identification of commonalities between tospoviruses and other bunyaviruses in transmission by arthropod vectors and molecular interactions with hosts. This review provides a special emphasis on TSWV and Frankliniella occidentalis, the model tospovirus-thrips pathosystem. However, other virus-vector combinations are also of importance and where possible, comparisons are made between different viruses and thrips vectors. PMID:26340723

  6. Onion Thrips, Thrips tabaci, Have Gut Bacteria That are Closely Related to the Symbionts of the Western Flower Thrips, Frankliniella occidentalis

    PubMed Central

    de Vries, Egbert J.; van der Wurff, André W. G.; Jacobs, Gerrit; Breeuwer, Johannes A. J.

    2008-01-01

    It has been shown that many insects have Enterobacteriaceae bacteria in their gut system. The western flower thrips, Frankliniella occidentalis Pergande [Thysanoptera: Thripidae], has a symbiotic relation with Erwinia species gut bacteria. To determine if other Thripidae species have similar bacterial symbionts, the onion thrips, Thrips tabaci, was studied because, like F. occidentalis, it is phytophagous. Contrary to F. occidentalis, T. tabaci is endemic in Europe and biotypes have been described. Bacteria were isolated from the majority of populations and biotypes of T. tabaci examined. Bacteria were present in high numbers in most individuals of the populations studied. Like F. occidentalis, T. tabaci contained one type of bacterium that clearly outnumbered all other types present in the gut. This bacterium was identified as an Erwinia species, as was also the case for F. occidentalis. However, its biochemical characteristics and 16S rDNA sequence differed from the bacteria present in F. occidentalis. PMID:20298113

  7. Development of a Ribosomal DNA ITS2 Marker for the Identification of the Thrips, Scirtothrips dorsalis

    PubMed Central

    Farris, R E; Ruiz-Arce, R; Ciomperlik, M; Vasquez, J D; DeLeón, R

    2010-01-01

    The thrips Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) is an invasive pest that poses a significant economical threat to U.S. agriculture and trade. In this study, DNA sequence data and polymerase chain reaction (PCR) were utilized to develop a molecular diagnostic marker for S. dorsalis. The DNA sequence variation from the internal transcribed spacer 2 (ITS2) region of nuclear ribosomal DNA (rDNA) was analyzed from various thrips species, including S. dorsalis. A primer set and polymerase chain reaction cycling parameters were designed for the amplification of a single marker fragment of S. dorsalis ITS2 rDNA. Specificity tests performed on ten thrips species, efficacy tests performed on fifteen S. dorsalis populations, and tests on primer sensitivity and robustness all demonstrated the diagnostic utility of this marker. This diagnostic PCR assay provides a quick, simple, and reliable molecular technique to be used in the identification of S. dorsalis. PMID:20578948

  8. Flight of the smallest insects

    NASA Astrophysics Data System (ADS)

    Miller, Laura; Santhanakrishnan, Arvind; Hedrick, Tyson; Robinson, Alice

    2009-11-01

    A vast body of research has described the complexity of flight in insects ranging from the fruit fly, Drosophila melanogaster, to the hawk moth, Manduca sexta. Over this range of scales, flight aerodynamics as well as the relative lift and drag forces generated are surprisingly similar. The smallest flying insects (Re˜10) have received far less attention, although previous work has shown that flight kinematics and aerodynamics can be significantly different. In this presentation, we have used a three-pronged approach that consists of measurements of flight kinematics in the tiny insect Thysanoptera (thrips), measurements of flow velocities using physical models, and direct numerical simulations to compute lift and drag forces. We find that drag forces can be an order of magnitude larger than lift forces, particularly during the clap and fling motion used by all tiny insects recorded to date.

  9. Development of a protocol for the identification of tospoviruses and thrips species in individual thrips.

    PubMed

    Seepiban, Channarong; Charoenvilaisiri, Saengsoon; Kumpoosiri, Mallika; Bhunchoth, Anjana; Chatchawankanphanich, Orawan; Gajanandana, Oraprapai

    2015-09-15

    A protocol for identifying tospovirus and thrips species in an individual thrips sample was successfully developed. First, an individual thrips was soaked in an RNA stabilization solution to preserve protein and nucleic acids and ground in a carbonate buffer containing 0.2% sodium diethyldithiocarbamate. Initially, the thrips extracts were screened for tospovirus infection by dot blot analysis using antibodies to nucleocapsid (N) proteins of tospoviruses. Thrips extracts with positive results by dot blot analysis were further subjected to RNA extraction. Next, tospovirus species were identified by reverse transcription-polymerase chain reaction (RT-PCR) using species-specific primers for the N genes of four tospoviruses known to occur in Thailand, including Capsicum chlorosis virus (CaCV), Melon yellow spot virus (MYSV), Tomato necrotic ringspot virus (TNRV) and Watermelon silver mottle virus (WSMoV). The residual genomic DNA in the thrips RNA extract was used as a template to identify thrips species by PCR with species-specific primers to the internal transcribed spacer 2 regions of the rRNA of Ceratothripoides claratris, Frankliniella intonsa, Scirtothrips dorsalis and Thrips palmi. This protocol was initially validated against laboratory-reared thrips and then used to determine the occurrence of viruliferous thrips species collected from tomato, pepper, watermelon and cucumber fields in Thailand.

  10. Preliminary study of urine metabolism in type two diabetic patients based on GC-MS

    PubMed Central

    Zhang, Ning; Geng, Fang; Hu, Zhong-Hua; Liu, Bin; Wang, Ye-Qiu; Liu, Jun-Cen; Qi, Yong-Hua; Li, Li-Jing

    2016-01-01

    Objective: Comparative study of type 2 diabetes and healthy controls by metabolomics methods to explore the pathogenesis of Type II diabetes. Methods: Gas chromatography - mass spectrometry (GC-MS) with a variety of multivariate statistical analysis methods to the healthy control group 58 cases, 68 cases of Type II diabetes group were analyzed. Chromatographic conditions: DB-5MS column; the carrier gas He; flow rate of 1 mL·min-1, the injection volume 1 uL; split ratio is 100: 1. MS conditions: electron impact (EI) ion source, an auxiliary temperature of 280°C, the ion source 230°C, quadrupole 150°C; mass scan range 30~600 mAu. Results: Established analytical method based on urine metabolomics GC-MS of Type II diabetes, determine the urine succinic acid, L-leucine, L-isoleucine, tyrosine, slanine, acetoace acid, mannose, L-isoleucine, L-threonine, Phenylalanine, fructose, D-glucose, palmi acid, oleic acid and arachidonic acid were significantly were significantly changed. Conclusion: Based on metabolomics of GC-MS detection and analysis metabolites can be found differences between type 2 diabetes and healthy control group, PCA diagram can effectively distinguish Type II diabetes and healthy control group, with load diagrams and PLS-DA VIP value metabolite screening, the resulting differences in metabolic pathways involved metabolites, including amino acid metabolism, lipid metabolism, glucose metabolism and energy metabolism. PMID:27508010

  11. Atmospheric deposition impacts on nutrients and biological budgets of the Mediterranean Sea, results from the high resolution coupled model NEMOMED12/PISCES

    NASA Astrophysics Data System (ADS)

    Richon, Camille; Dutay, Jean-Claude; Dulac, François; Desboeufs, Karine; Nabat, Pierre; Guieu, Cécile; Aumont, Olivier; Palmieri, Julien

    2016-04-01

    Atmospheric deposition is at present not included in regional oceanic biogeochemical models of the Mediterranean Sea, whereas, along with river inputs, it represents a significant source of nutrients at the basin scale, especially through intense desert dust events. Moreover, observations (e.g. DUNE campaign, Guieu et al. 2010) show that these events significantly modify the biogeochemistry of the oligotrophic Mediterranean Sea. We use a high resolution (1/12°) version of the 3D coupled model NEMOMED12/PISCES to investigate the effects of high resolution atmospheric dust deposition forcings on the biogeochemistry of the Mediterranean basin. The biogeochemical model PISCES represents the evolution of 24 prognostic tracers including five nutrients (nitrate, ammonium, phosphate, silicate and iron) and two phytoplankton and zooplanktons groups (Palmiéri, 2014). From decadal simulations (1982-2012) we evaluate the influence of natural dust and anthropogenic nitrogen deposition on the budget of nutrients in the basin and its impact on the biogeochemistry (primary production, plankton distributions...). Our results show that natural dust deposition accounts for 15% of global PO4 budget and that it influences primarily the southern part of the basin. Anthropogenic nitrogen accounts for 50% of bioavailable N supply for the northern part. Deposition events significantly affect biological production; primary productivity enhancement can be as high as 30% in the areas of high deposition, especially during the stratified period. Further developments of the model will include 0D and 1D modeling of bacteria in the frame of the PEACETIME project.

  12. Seafloor characterization and benthic megafaunal distribution of an active submarine canyon and surrounding sectors: The case of Gioia Canyon (Southern Tyrrhenian Sea)

    NASA Astrophysics Data System (ADS)

    Pierdomenico, Martina; Martorelli, Eleonora; Dominguez-Carrió, Carlos; Gili, Josep Maria; Chiocci, Francesco Latino

    2016-05-01

    In this paper, we used multibeam bathymetry and backscatter, high-resolution seismic profiles, ROV video images and sediment samples to identify the principal morpho-sedimentary features and related megabenthic communities along the upper reach of the Gioia Canyon (depth < 600 m) and the surrounding shelf and slope areas. Interpretation of the multidisciplinary dataset was undertaken to evaluate the relationships between seafloor characteristics and faunal distribution along a submarine canyon in an active tectonic setting. The results from this study indicate that physical disturbance on the seafloor at the canyon head and surrounding shelf, related to high sedimentation rates and occasional turbidite flows, may limit the variability of megabenthic communities. Evidence of diffuse trawl marks over soft sedimentary bottoms indicates anthropogenic impact due to fishing activities, which could explain low abundances of megabenthic species observed locally. The canyon margins and flanks along the continental slope host octocorals Funiculina quadrangularis and Isidella elongata, species that are indicative of vulnerable marine ecosystems (VMEs) and relevant in terms of sustainable management priorities. At the Palmi Ridge, the occurrence of outcropping rocks and bottom currents related to the presence of Levantine Intermediate Waters, provide conditions for the development of hard-bottom assemblages, including the black coral Antipathella subpinnata and deep-sea sponges fields.

  13. Development of a protocol for the identification of tospoviruses and thrips species in individual thrips.

    PubMed

    Seepiban, Channarong; Charoenvilaisiri, Saengsoon; Kumpoosiri, Mallika; Bhunchoth, Anjana; Chatchawankanphanich, Orawan; Gajanandana, Oraprapai

    2015-09-15

    A protocol for identifying tospovirus and thrips species in an individual thrips sample was successfully developed. First, an individual thrips was soaked in an RNA stabilization solution to preserve protein and nucleic acids and ground in a carbonate buffer containing 0.2% sodium diethyldithiocarbamate. Initially, the thrips extracts were screened for tospovirus infection by dot blot analysis using antibodies to nucleocapsid (N) proteins of tospoviruses. Thrips extracts with positive results by dot blot analysis were further subjected to RNA extraction. Next, tospovirus species were identified by reverse transcription-polymerase chain reaction (RT-PCR) using species-specific primers for the N genes of four tospoviruses known to occur in Thailand, including Capsicum chlorosis virus (CaCV), Melon yellow spot virus (MYSV), Tomato necrotic ringspot virus (TNRV) and Watermelon silver mottle virus (WSMoV). The residual genomic DNA in the thrips RNA extract was used as a template to identify thrips species by PCR with species-specific primers to the internal transcribed spacer 2 regions of the rRNA of Ceratothripoides claratris, Frankliniella intonsa, Scirtothrips dorsalis and Thrips palmi. This protocol was initially validated against laboratory-reared thrips and then used to determine the occurrence of viruliferous thrips species collected from tomato, pepper, watermelon and cucumber fields in Thailand. PMID:26141731

  14. Characterization of motor skill and instrumental learning time scales in a skilled reaching task in rat.

    PubMed

    Buitrago, Manuel M; Ringer, Thomas; Schulz, Jörg B; Dichgans, Johannes; Luft, Andreas R

    2004-12-01

    Successful motor skill learning requires repetitive training interrupted by rest periods. In humans, improvement occurs within and between training sessions reflecting fast and slow components of motor learning [Karni A, Meyer G, Rey-Hipolito C, Jezzard P, Adams MM, Turner R, et al. The acquisition of skilled motor performance: fast and slow experience-driven changes in primary motor cortex. Proc Natl Acad Sci USA 1998;95:861-8]. Here, these components are characterized in male and female rats using a model of skilled forelimb reaching and are compared to time scales of instrumental learning. Twenty female and 14 male adult Long-Evans rats were pre-trained to operate a motorized door (via a sensor in the opposite cage wall) to access a food pellet by tongue. Latencies between pellet removal and door opening were recorded as measures of instrumental learning. After criterion performance was achieved, skilled forelimb reaching was requested by increasing the pellet-window distance to 1.5cm. Reaching success was recorded per trial. Mean latencies decreased exponentially over sessions and no improvement within-session was found. Skill learning over eight training sessions followed an exponential course in females and a sigmoid course in males. Females acquired the skill significantly faster than males starting at higher baseline levels (P < 0.001) but reaching similar plateaus. Within-session improvement was found during the sessions 1-3 in females and 1-4 in males. Performance at the end of session 1 was not carried over to session 2. Learning curves of individual animals were highly variable. These findings confirm in rat that motor skill learning has fast and slow components. No within-session improvement is seen in instrumental learning.

  15. RNA interference tools for the western flower thrips, Frankliniella occidentalis.

    PubMed

    Badillo-Vargas, Ismael E; Rotenberg, Dorith; Schneweis, Brandi A; Whitfield, Anna E

    2015-05-01

    The insect order Thysanoptera is exclusively comprised of small insects commonly known as thrips. The western flower thrips, Frankliniella occidentalis, is an economically important pest amongst thysanopterans due to extensive feeding damage and tospovirus transmission to hundreds of plant species worldwide. Geographically-distinct populations of F. occidentalis have developed resistance against many types of traditional chemical insecticides, and as such, management of thrips and tospoviruses are a persistent challenge in agriculture. Molecular methods for defining the role(s) of specific genes in thrips-tospovirus interactions and for assessing their potential as gene targets in thrips management strategies is currently lacking. The goal of this work was to develop an RNA interference (RNAi) tool that enables functional genomic assays and to evaluate RNAi for its potential as a biologically-based approach for controlling F. occidentalis. Using a microinjection system, we delivered double-stranded RNA (dsRNA) directly to the hemocoel of female thrips to target the vacuolar ATP synthase subunit B (V-ATPase-B) gene of F. occidentalis. Gene expression analysis using real-time quantitative reverse transcriptase-PCR (qRT-PCR) revealed significant reductions of V-ATPase-B transcripts at 2 and 3 days post-injection (dpi) with dsRNA of V-ATPase-B compared to injection with dsRNA of GFP. Furthermore, the effect of knockdown of the V-ATPase-B gene in females at these two time points was mirrored by the decreased abundance of V-ATPase-B protein as determined by quantitative analysis of Western blots. Reduction in V-ATPase-B expression in thrips resulted in increased female mortality and reduced fertility, i.e., number of viable offspring produced. Survivorship decreased significantly by six dpi compared to the dsRNA-GFP control group, which continued decreasing significantly until the end of the bioassay. Surviving female thrips injected with dsRNA-V-ATPase-B produced

  16. Occurrence of entomopathogenic fungi from agricultural and natural ecosystems in Saltillo, México, and their virulence towards thrips and whiteflies.

    PubMed

    Sánchez-Peña, Sergio R; Lara, Jorge San-Juan; Medina, Raúl F

    2011-01-01

    Entomopathogenic fungi were collected from soil in four adjacent habitats (oak forest, agricultural soil, pine reforestation and chaparral habitat) in Saltillo, México using the insect bait method with Tenebrio molitor (L.) (Coleoptera: Tenebrionidae) larvae as bait. Overall, of the larvae exposed to soil, 171 (20%) hosted Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), 25 (3%) hosted Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and 1 (0.1%) hosted lsaria (=Paecilomyces) sp. (Hypocreales: Cordycipitaceae). B. bassiana was significantly more frequent on larvae exposed to oak forest soil. M. anisopliae was significantly more frequent on larvae exposed to agricultural soil. From the infected bait insects, 93 isolates of B. bassiana and 24 isolates of M. anisopliae were obtained. Strains were tested for their infectivity against Cuban laurel thrips, Gynaikothrips uzeli Zimmerman (Thysanoptera: Phlaeothripidae) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae). B. bassiana isolates caused the highest mortality on thrips (some causing 88% mortality after 6 days); both fungal species caused similarly high mortality levels against whiteflies (75%) after 6 days. Large amounts of germplasm of entomopathogenic fungi, fundamentally B. bassiana and M. anisopliae, exist in the habitats sampled; pathogenicity varied among strains, and some strains possessed significant virulence. Soils in these habitats are reservoirs of diverse strains with potential for use in biocontrol.

  17. Stable Reference Gene Selection for RT-qPCR Analysis in Nonviruliferous and Viruliferous Frankliniella occidentalis.

    PubMed

    Yang, Chunxiao; Li, Hui; Pan, Huipeng; Ma, Yabin; Zhang, Deyong; Liu, Yong; Zhang, Zhanhong; Zheng, Changying; Chu, Dong

    2015-01-01

    Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for measuring and evaluating gene expression during variable biological processes. To facilitate gene expression studies, normalization of genes of interest relative to stable reference genes is crucial. The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), the main vector of tomato spotted wilt virus (TSWV), is a destructive invasive species. In this study, the expression profiles of 11 candidate reference genes from nonviruliferous and viruliferous F. occidentalis were investigated. Five distinct algorithms, geNorm, NormFinder, BestKeeper, the ΔCt method, and RefFinder, were used to determine the performance of these genes. geNorm, NormFinder, BestKeeper, and RefFinder identified heat shock protein 70 (HSP70), heat shock protein 60 (HSP60), elongation factor 1 α, and ribosomal protein l32 (RPL32) as the most stable reference genes, and the ΔCt method identified HSP60, HSP70, RPL32, and heat shock protein 90 as the most stable reference genes. Additionally, two reference genes were sufficient for reliable normalization in nonviruliferous and viruliferous F. occidentalis. This work provides a foundation for investigating the molecular mechanisms of TSWV and F. occidentalis interactions. PMID:26244556

  18. Colored Sticky Traps to Selectively Survey Thrips in Cowpea Ecosystem.

    PubMed

    Tang, L D; Zhao, H Y; Fu, B L; Han, Y; Liu, K; Wu, J H

    2016-02-01

    The bean flower thrips, Megalurothrips usitatus (Bagrall) (Thysanoptera: Thripidae), is an important pest of legume crops in South China. Yellow, blue, or white sticky traps are currently recommended for monitoring and controlling thrips, but it is not known whether one is more efficient than the other or if selectivity could be optimized by trap color. We investigated the response of thrips and beneficial insects to different-colored sticky traps on cowpea, Vigna unguiculata. More thrips were caught on blue, light blue, white, and purple traps than on yellow, green, pink, gray, red, or black traps. There was a weak correlation on the number of thrips caught on yellow traps and survey from flowers (r = 0.139), whereas a strong correlation was found for blue traps and thrips' survey on flowers (r = 0.929). On commercially available sticky traps (Jiaduo®), two and five times more thrips were caught on blue traps than on white and yellow traps, respectively. Otherwise, capture of beneficial insects was 1.7 times higher on yellow than on blue traps. The major natural enemies were the predatory ladybird beetles (63%) and pirate bugs Orius spp. (29%), followed by a number of less representative predators and parasitoids (8%). We conclude the blue sticky trap was the best to monitor thrips on cowpea in South China. PMID:26429578

  19. The molecular action of the novel insecticide, Pyridalyl.

    PubMed

    Powell, Gerard F; Ward, Deborah A; Prescott, Mark C; Spiller, David G; White, Michael R H; Turner, Phillip C; Earley, Fergus G P; Phillips, Janet; Rees, Huw H

    2011-07-01

    Pyridalyl is a recently discovered insecticide that exhibits high insecticidal activity against Lepidoptera and Thysanoptera. Pyridalyl action requires cytochrome P450 activity, possibly for production of a bioactive derivative, Pyridalyl metabolism being prevented by general P450 inhibitors. Apoptosis is apparently not involved in the cytotoxicity. Continuous culture of Spodoptera frugiperda Sf21 cells in sub-lethal doses of Pyridalyl, results in a Pyridalyl-resistant cell line. Probing the molecular action of Pyridalyl by comparison of the proteomes of Pyridalyl-resistant and -susceptible cell lines, revealed differential expression of a number of proteins, including the up-regulation of thiol peroxiredoxin (TPx), in the resistant cells. Treatment of Bombyx mori larvae with Pyridalyl, followed by comparison of the midgut microsomal sub-proteome, revealed the up-regulation of three proteasome subunits. Such subunits, together with Hsp70 stress proteins, glyceraldehyde 3-phosphate dehydrogenases (GAPDHs) and thiol peroxiredoxin (TPx) were also up-regulated in the whole proteome of B. mori BM36 cells following treatment with the insecticide. The foregoing results lead to the hypothesis that cytochrome P450 action leads to an active Pyridalyl metabolite, which results in production of reactive oxygen species (ROS), that leads to damage to cellular macromolecules (e.g., proteins) and enhanced proteasome activity leads to increased protein degradation and necrotic cell death.

  20. Diversity of insect galls associated with coastal shrub vegetation in Rio de Janeiro, Brazil.

    PubMed

    Carvalho-Fernandes, Sheila P; Ascendino, Sharlene; Maia, Valéria C; Couri, Márcia S

    2016-09-01

    Surveys in the coastal sandy plains (restingas) of Rio de Janeiro have shown a great richness of galls. We investigated the galling insects in two preserved restingas areas of Rio de Janeiro state: Parque Estadual da Costa do Sol and Reserva Particular do Patrimônio Natural Fazenda Caruara. The collections were done each two months, from June 2011 to May 2012. We investigated 38 points during 45 minutes each per collection. The galls were taken to the laboratory for rearing the insects. A total number of 151 insect galls were found in 82 plant species distributed into 34 botanic families. Most of the galls occurred on leaves and the plant families with the highest richness of galls were Myrtaceae and Fabaceae. All the six insect orders with galling species were found in this survey, where Cecidomyiidae (Diptera) was the main galler group. Hymenoptera and Thysanoptera were found as parasitoids and inquilines in 29 galls. The richness of galls in the surveyed areas reveals the importance of restinga for the composition and diversity of gall-inducing insect fauna.

  1. Influences of extreme weather, climate and pesticide use on invertebrates in cereal fields over 42 years.

    PubMed

    Ewald, Julie A; Wheatley, Christopher J; Aebischer, Nicholas J; Moreby, Stephen J; Duffield, Simon J; Crick, Humphrey Q P; Morecroft, Michael B

    2015-11-01

    Cereal fields are central to balancing food production and environmental health in the face of climate change. Within them, invertebrates provide key ecosystem services. Using 42 years of monitoring data collected in southern England, we investigated the sensitivity and resilience of invertebrates in cereal fields to extreme weather events and examined the effect of long-term changes in temperature, rainfall and pesticide use on invertebrate abundance. Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae. The average abundance of Delphacidae, Cryptophagidae and Mycetophilidae increased in both hot/dry and cold/wet years relative to other years. The abundance of all 10 groups usually returned to their long-term trend within a year after the extreme event. For five of them, sensitivity to cold/wet events was lowest (translating into higher abundances) at locations with a westerly aspect. Some long-term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change. PMID:26149473

  2. Influences of extreme weather, climate and pesticide use on invertebrates in cereal fields over 42 years.

    PubMed

    Ewald, Julie A; Wheatley, Christopher J; Aebischer, Nicholas J; Moreby, Stephen J; Duffield, Simon J; Crick, Humphrey Q P; Morecroft, Michael B

    2015-11-01

    Cereal fields are central to balancing food production and environmental health in the face of climate change. Within them, invertebrates provide key ecosystem services. Using 42 years of monitoring data collected in southern England, we investigated the sensitivity and resilience of invertebrates in cereal fields to extreme weather events and examined the effect of long-term changes in temperature, rainfall and pesticide use on invertebrate abundance. Of the 26 invertebrate groups examined, eleven proved sensitive to extreme weather events. Average abundance increased in hot/dry years and decreased in cold/wet years for Araneae, Cicadellidae, adult Heteroptera, Thysanoptera, Braconidae, Enicmus and Lathridiidae. The average abundance of Delphacidae, Cryptophagidae and Mycetophilidae increased in both hot/dry and cold/wet years relative to other years. The abundance of all 10 groups usually returned to their long-term trend within a year after the extreme event. For five of them, sensitivity to cold/wet events was lowest (translating into higher abundances) at locations with a westerly aspect. Some long-term trends in invertebrate abundance correlated with temperature and rainfall, indicating that climate change may affect them. However, pesticide use was more important in explaining the trends, suggesting that reduced pesticide use would mitigate the effects of climate change.

  3. Two new species of Scirtothrips genus-group (Thripidae) of Northern Peninsular Malaysia.

    PubMed

    Ng, Y F; Mound, L A

    2016-03-07

    The survey of Thysanoptera in peninsular Malaysia has been concentrated largely in areas growing crops and flowers around Kuala Lumpur, and the Cameron Highlands, and there are few records of these insects from native forests particularly in the northern part of the country. The two species described here were collected during a recent visit to Belum-Temengor Forest Complex, in Perak State, part of the second largest forested area on the peninsular, and connected to the Bang Lang National Park, in Yala Province, Thailand. This forest has been well known as home to a number of endangered animals, including Malayan tigers and Asian elephants, as well as remarkable plant species such as Rafflesia with the world's largest flowers (Abdullah et al. 2011). Despite this, forest areas are facing a major challenge from the insatiable demand for timber, palm oil and minerals, with an 80% increase in deforestation rate in Malaysia between 1990 and 2005 (FAO 2010). Forested land in peninsular Malaysia has been estimated at 5.88 million-ha or 44% of total area, but the coverage of reserved virgin forest is about 0.40 % or 23,002-ha (Dahlan 2008).

  4. Continuous exposure to the deterrents cis-jasmone and methyl jasmonate does not alter the behavioural responses of Frankliniella occidentalis

    PubMed Central

    Egger, Barbara; Spangl, Bernhard; Koschier, Elisabeth Helene

    2016-01-01

    Behavioural responses of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), a generalist, cell sap-feeding insect species with piercing-sucking mouthparts, after continuous exposure to two deterrent secondary plant compounds are investigated. We compared in choice assays on bean leaf discs, the settling, feeding, and oviposition preferences of F. occidentalis females that had no experience with the two fatty acid derivatives methyl jasmonate and cis-jasmone before testing (naïve thrips) vs. females that had been exposed to the deterrent compounds before testing (experienced thrips). The thrips were exposed to the deterrents at low or high concentrations for varied time periods and subsequently tested on bean leaf discs treated with the respective deterrent at either a low or a high concentration. Frankliniella occidentalis females avoided settling on the deterrent-treated bean leaf discs for an observation period of 6 h, independent of their previous experience. Our results demonstrate that feeding and oviposition deterrence of the jasmonates to the thrips were not altered by continuous exposure of the thrips to the jasmonates. Habituation was not induced, neither by exposure to the low concentration of the deterrents nor by exposure to the high concentration. These results indicate that the risk of habituation to two volatile deterrent compounds after repeated exposure is not evident in F. occidentalis. This makes the two compounds potential candidates to be integrated in pest management strategies. PMID:26726263

  5. Susceptibility of Dalotia coriaria (Kraatz) (Coleoptera: Staphylinidae) to Entomopathogenic Nematodes (Rhabditida: Heterorhabditidae and Steinernematidae)

    PubMed Central

    Tourtois, Joseph; Grieshop, Matthew J.

    2015-01-01

    Dalotia coriaria (Kraatz) (Coleoptera: Staphylinidae) and entomopathogenic nematodes (Rhabditida: Heterorhabditidae and Steinernematidae) are two soil-dwelling biological control agents used to manage western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) and fungus gnats Bradysis spp. (Diptera: Sciaridae) in glasshouses. Growers often use multiple natural enemies to achieve economic control, but knowledge of interactions among natural enemies is lacking. We conducted a laboratory bioassay to test the pathogenicity of four commercially available nematode species—Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhbditidae), Steinernema carpocapsae (Weiser) (Rhabditida: Steinernematidae), S. feltiae (Filipjev), and S. riobrave Cabanillas et al.—to third instar and adult D. coriaria. Third instars were three times more susceptible than the adults to the entomopathogenic nematodes. Mortality for D. coriaria adults and third instars treated with S. feltiae and H. bacteriophora was lower than the mortality for D. coriaria adults and third instars treated with S. carpocapsae and S. riobrave. Neither infective juvenile foraging behavior nor size correlates with D. coriaria mortality. Dalotia coriaria appears to be most likely compatible with applications of S. feltiae and H. bacteriophora. PMID:26463077

  6. The green lacewing, Chrysoperla carnea: preference between lettuce aphids, Nasonovia ribisnigri, and Western flower thrips, Frankliniella occidentalis.

    PubMed

    Shrestha, Govinda; Enkegaard, Annie

    2013-01-01

    This study investigated the prey preference of 3(rd) instar green lacewing, Chrysoperla carnea Stephens (Neuroptera: Chrysopidae), between western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and lettuce aphids, Nasonovia ribisnigri (Mosley) (Hemiptera: Aphididae) in laboratory experiments at 25 ± 1° C and 70 ± 5% RH with five prey ratios (10 aphids:80 thrips, 25 aphids:65 thrips, 45 aphids:45 thrips, 65 aphids:25 thrips, and 80 aphids:10 thrips). Third instar C. carnea larvae readily preyed upon both thrips and aphids, with thrips mortality varying between 40 and 90%, and aphid mortality between 52 and 98%. Chrysoperla carnea had a significant preference for N. ribisnigri at two ratios (10 aphids:80 thrips, 65 aphids:25 thrips), but no preference for either prey at the other ratios. There was no significant linear relationship between preference index and prey ratio, but a significant intercept of the linear regression indicated an overall preference of C. carnea for aphids with a value of 0.651 ± 0.054. The possible implications of these findings for control of N. ribisnigri and F. occidentalis by C. carnea are discussed.

  7. Diversity of insect galls associated with coastal shrub vegetation in Rio de Janeiro, Brazil.

    PubMed

    Carvalho-Fernandes, Sheila P; Ascendino, Sharlene; Maia, Valéria C; Couri, Márcia S

    2016-09-01

    Surveys in the coastal sandy plains (restingas) of Rio de Janeiro have shown a great richness of galls. We investigated the galling insects in two preserved restingas areas of Rio de Janeiro state: Parque Estadual da Costa do Sol and Reserva Particular do Patrimônio Natural Fazenda Caruara. The collections were done each two months, from June 2011 to May 2012. We investigated 38 points during 45 minutes each per collection. The galls were taken to the laboratory for rearing the insects. A total number of 151 insect galls were found in 82 plant species distributed into 34 botanic families. Most of the galls occurred on leaves and the plant families with the highest richness of galls were Myrtaceae and Fabaceae. All the six insect orders with galling species were found in this survey, where Cecidomyiidae (Diptera) was the main galler group. Hymenoptera and Thysanoptera were found as parasitoids and inquilines in 29 galls. The richness of galls in the surveyed areas reveals the importance of restinga for the composition and diversity of gall-inducing insect fauna. PMID:27627066

  8. Effect of Different Temperatures on Consumption of Two Spotted Mite, Tetranychus urticae, Eggs by the Predatory Thrips, Scolothrips longicornis

    PubMed Central

    Pakyari, Hajar; Enkegaard, Annie

    2012-01-01

    Environmental variables such as temperature are important factors affecting the efficacy of biological control agents. This study evaluated the predation rate of the predatory thrips Scolothrips longicornis Priesner (Thysanoptera: Thripidae) against the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) under laboratory conditions. Based on daily and total prey consumption of different life stages of S. longicornis on spider mite eggs at temperatures covering the range suitable for development and survival of the predator (15° C to 37° C, 60 ± 10% RH, 16:8 L:D), there was a significant effect of temperature on prey consumption. The number of prey consumed daily by first and second instar larvae increased linearly with increasing temperature from 15 °C to 37 °C, whereas daily consumption of preovipositing and postovipositing females was uninfluenced by temperature. Lower temperature thresholds for consumption by first and second instar larvae of S. longicornis was estimated to be 6.8 ± 0.04° C and 4.6 ± 0.03° C, respectively. The daily consumption of ovipositing females followed a nonlinear pattern, with maximum daily predation estimated at 32.8° C. From the model used to describe consumption of ovipositing females, an upper threshold for consumption of 41.4° C was estimated. The performance of S. longicornis at the different temperatures is discussed in relation to its practical use in integrated pest control programs. PMID:23425212

  9. Stable Reference Gene Selection for RT-qPCR Analysis in Nonviruliferous and Viruliferous Frankliniella occidentalis

    PubMed Central

    Pan, Huipeng; Ma, Yabin; Zhang, Deyong; Liu, Yong; Zhang, Zhanhong; Zheng, Changying; Chu, Dong

    2015-01-01

    Reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) is a reliable technique for measuring and evaluating gene expression during variable biological processes. To facilitate gene expression studies, normalization of genes of interest relative to stable reference genes is crucial. The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), the main vector of tomato spotted wilt virus (TSWV), is a destructive invasive species. In this study, the expression profiles of 11 candidate reference genes from nonviruliferous and viruliferous F. occidentalis were investigated. Five distinct algorithms, geNorm, NormFinder, BestKeeper, the ΔCt method, and RefFinder, were used to determine the performance of these genes. geNorm, NormFinder, BestKeeper, and RefFinder identified heat shock protein 70 (HSP70), heat shock protein 60 (HSP60), elongation factor 1 α, and ribosomal protein l32 (RPL32) as the most stable reference genes, and the ΔCt method identified HSP60, HSP70, RPL32, and heat shock protein 90 as the most stable reference genes. Additionally, two reference genes were sufficient for reliable normalization in nonviruliferous and viruliferous F. occidentalis. This work provides a foundation for investigating the molecular mechanisms of TSWV and F. occidentalis interactions. PMID:26244556

  10. Occurrence of Entomopathogenic Fungi from Agricultural and Natural Ecosystems in Saltillo, México, and their Virulence Towards Thrips and Whiteflies

    PubMed Central

    Sánchez-Peña, Sergio R.; Lara, Jorge San-Juan; Medina, Raúl F.

    2011-01-01

    Entomopathogenic fungi were collected from soil in four adjacent habitats (oak forest, agricultural soil, pine reforestation and chaparral habitat) in Saltillo, México using the insect bait method with Tenebrio molitor (L.) (Coleoptera: Tenebrionidae) larvae as bait. Overall, of the larvae exposed to soil, 171 (20%) hosted Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), 25 (3%) hosted Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and 1 (0.1%) hosted lsaria (=Paecilomyces) sp. (Hypocreales: Cordycipitaceae). B. bassiana was significantly more frequent on larvae exposed to oak forest soil. M. anisopliae was significantly more frequent on larvae exposed to agricultural soil. From the infected bait insects, 93 isolates of B. bassiana and 24 isolates of M. anisopliae were obtained. Strains were tested for their infectivity against Cuban laurel thrips, Gynaikothrips uzeli Zimmerman (Thysanoptera: Phlaeothripidae) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae). B. bassiana isolates caused the highest mortality on thrips (some causing 88% mortality after 6 days); both fungal species caused similarly high mortality levels against whiteflies (75%) after 6 days. Large amounts of germplasm of entomopathogenic fungi, fundamentally B. bassiana and M. anisopliae, exist in the habitats sampled; pathogenicity varied among strains, and some strains possessed significant virulence. Soils in these habitats are reservoirs of diverse strains with potential for use in biocontrol. PMID:21521145

  11. The diversity and abundance of small arthropods in onion, Allium cepa, seed crops, and their potential role in pollination.

    PubMed

    Walker, M K; Howlett, B G; Wallace, A R; McCallum, J A; Teulon, D A J

    2011-01-01

    Onion, Allium cepa L. (Asparagales: Amaryllidaceae), crop fields grown for seed production require arthropod pollination for adequate seed yield. Although many arthropod species visit A. cepa flowers, for most there is little information on their role as pollinators. Small flower visiting arthropods (body width < 3 mm) in particular are rarely assessed. A survey of eight flowering commercial A. cepa seed fields in the North and South Islands of New Zealand using window traps revealed that small arthropods were highly abundant among all except one field. Insects belonging to the orders Diptera and Thysanoptera were the most abundant and Hymenoptera, Collembola, Psocoptera, Hemiptera, and Coleoptera were also present. To test whether small arthropods might contribute to pollination, seed sets from umbels caged within 3 mm diameter mesh cages were compared with similarly caged, hand-pollinated umbels and uncaged umbels. Caged umbels that were not hand-pollinated set significantly fewer seeds (average eight seeds/umbel, n = 10) than caged hand-pollinated umbels (average 146 seeds/umbel) and uncaged umbels (average 481 seeds/umbel). Moreover, sticky traps placed on umbels within cages captured similar numbers of small arthropods as sticky traps placed on uncaged umbels, suggesting cages did not inhibit the movement of small arthropods to umbels. Therefore, despite the high abundance of small arthropods within fields, evidence to support their role as significant pollinators of commercial A. cepa seed crops was not found.

  12. Perception of solar UVB radiation by phytophagous insects: Behavioral responses and ecosystem implications

    PubMed Central

    Mazza, Carlos A.; Zavala, Jorge; Scopel, Ana L.; Ballaré, Carlos L.

    1999-01-01

    Most of our present knowledge about the impacts of solar UVB radiation on terrestrial ecosystems comes from studies with plants. Recently, the effects of UVB on the growth and survival of consumer species have begun to receive attention, but very little is known about UVB impacts on animal behavior. Here we report that manipulations of the flux of solar UVB received by field-grown soybean crops had large and consistent effects on the density of the thrips (Caliothrips phaseoli, Thysanoptera: Thripidae) populations that invaded the canopies, as well as on the amount of leaf damage caused by the insects. Solar UVB strongly reduced thrips herbivory. Thrips not only preferred leaves from plants that were not exposed to solar UVB over leaves from UVB-exposed plants in laboratory and field choice experiments, but they also appeared to directly sense and avoid exposure to solar UVB. Additional choice experiments showed that soybean leaf consumption by the late-season soybean worm Anticarsia gemmatalis (Lepidoptera: Noctuidae) was much less intense in leaves with even slight symptoms of an early thrips attack than in undamaged leaves. These experiments suggest that phytophagous insects can present direct and indirect behavioral responses to solar UVB. The indirect responses are mediated by changes in the plant host that are induced by UVB and, possibly, by other insects whose behavior is affected by UVB. PMID:9927679

  13. Development and characterization of 18 novel EST-SSRs from the western flower Thrips, Frankliniella occidentalis (Pergande).

    PubMed

    Yang, Xian-Ming; Sun, Jing-Tao; Xue, Xiao-Feng; Zhu, Wen-Chao; Hong, Xiao-Yue

    2012-01-01

    The western flower thrips, Frankliniella occidentalis (Pergande), is an invasive species and the most economically important pest within the insect order Thysanoptera. For a better understanding of the genetic makeup and migration patterns of F. occidentalis throughout the world, we characterized 18 novel polymorphic EST-derived microsatellites. The mutational mechanism of these EST-SSRs was also investigated to facilitate the selection of appropriate combinations of markers for population genetic studies. Genetic diversity of these novel markers was assessed in 96 individuals from three populations in China (Harbin, Dali, and Guiyang). The results showed that all these 18 loci were highly polymorphic; the number of alleles ranged from 2 to 15, with an average of 5.50 alleles per locus. The observed (H(O)) and expected (H(E)) heterozygosities ranged from 0.072 to 0.707 and 0.089 to 0.851, respectively. Furthermore, only two locus/population combinations (WFT144 in Dali and WFT50 in Guiyang) significantly deviated from Hardy-Weinberg equilibrium (HWE). Pairwise F(ST) analysis showed a low but significant differentiation (0.026 < F(ST) < 0.032) among all three pairwise population comparisons. Sequence analysis of alleles per locus revealed a complex mutational pattern of these EST-SSRs. Thus, these EST-SSRs are useful markers but greater attention should be paid to the mutational characteristics of these microsatellites when they are used in population genetic studies.

  14. Active aggregation among sexes in bean flower thrips (Megalurothrips sjostedti) on cowpea (Vigna unguiculata)

    PubMed Central

    Niassy, Saliou; Ekesi, Sunday; Maniania, Nguya K; Orindi, Benedict; Moritz, Gerald B; de Kogel, Willem J; Subramanian, Sevgan

    2016-01-01

    Male sexual aggregations are a common territorial, mating-related or resource-based, behaviour observed in diverse organisms, including insects such as thrips. The influence of factors such as plant substrate, time of day, and geographic location on aggregation of thrips is uncertain, therefore we monitored the dispersion of male and female bean flower thrips (BFT), Megalurothrips sjostedti (Trybom) (Thysanoptera: Thripidae), on cowpea, Vigna unguiculata (L.) Walp. (Fabaceae), over three cowpea growth stages and across three cowpea-growing areas of Kenya. Our results indicated that for all the crop growth stages, the density of BFTs varied over the time of day, with higher densities at 10:00, 13:00, and 16:00 hours than at 07:00 hours. Thrips densities did not differ among blocks at the budding stage, but they did at peak flowering and podding stages. Dispersion indices suggested that both male and female BFTs were aggregated. Active male aggregation occurred only on green plant parts and it varied across blocks, crop stages, and locations. Similarly, active female aggregation was observed in peak flowering and podding stages. Such active aggregation indicates a semiochemical or behaviour-mediated aggregation. Identification of such a semiochemical may offer new opportunities for refining monitoring and management strategies for BFT on cowpea, the most important grain legume in sub-Saharan Africa. PMID:26726262

  15. Intra- and interspecific molecular polymorphism of thrips species.

    PubMed

    Bayar, K; Törjék, O; Kiss, Erzsébet; Gyulai, G; Heszky, L

    2002-01-01

    Molecular polymorphism of six species of Thysanoptera of both sexes, collected from different locations and host plants in Hungary was studied by using RAPD-PCR technique. The specimens were classified according to sampling sites (Gödöllö, Nagykovácsi and Valkó), host plants (Lathyrus tuberosus, Medicago sativa, Taraxacum officinale, Trifolium pratense), sexes, and larvae in case of Aeolothrips intermedius. On the basis of the total of 103 fragments generated by 15 RAPD primers the genetic distances were calculated by cluster analysis using simple matching method. The dendrogram resulted in two main groups: Aeolothripidae (Aeolothrips intermedius) and Thripidae (Frankliniella intonsa, Kakothrips robustus, Odontothrips confusus, Thrips dilatatus and T. tabaci). Within the family Thripidae two subgroups were observed including (i) F. intonsa, T. dilatatus and T. tabaci, and (ii) K. robustus and O. confusus. Two population-specific and one sex-linked fragments were identified by the RAPD primers, OPQ 14, NO11 and OPA08, respectively.

  16. Ontogenetic shifts in intraguild predation on thrips by phytoseiid mites: the relevance of body size and diet specialization.

    PubMed

    Walzer, A; Paulus, H F; Schausberger, P

    2004-12-01

    In greenhouse agroecosystems, a guild of spider mite predators may consist of the oligophagous predatory mite Phytoseiulus persimilis Athias-Henriot, the polyphagous predatory mite Neoseiulus californicus McGregor (both Acari: Phytoseiidae) and the primarily herbivorous but facultatively predatory western flower thrips Frankliniella occidentalis Pergande (Thysanoptera: Thripidae). Diet-specialization and the predator body size relative to prey are crucial factors in predation on F. occidentalis by P. persimilis and N. californicus. Here, it was tested whether the relevance of these factors changes during predator ontogeny. First, the predator (protonymphs and adult females of P. persimilis and N. californicus): prey (F. occidentalis first instars) body size ratios were measured. Second, the aggressiveness of P. persimilis and N. californicus towards F. occidentalis was assessed. Third, survival, development and oviposition of P. persimilis and N. californicus with F. occidentalis prey was determined. The body size ranking was P. persimilis females > N. californicus females > P. persimilis protonymphs > N. californicus protonymphs. Neoseiulus californicus females were the most aggressive predators, followed by highly aggressive N. californicus protonymphs and moderately aggressive P. persimilis protonymphs. Phytoseiulus persimilis females did not attack thrips. Frankliniella occidentalis larvae are an alternative prey for juvenile N. californicus and P. persimilis, enabling them to reach adulthood. Females of N. californicus but not P. persimilis sustained egg production with thrips prey. Within the guild studied here, N. californicus females are the most harmful predators for F. occidentalis larvae, followed by N. californicus and P. persimilis juveniles. Phytoseiulus persimilis females are harmless to F. occidentalis.

  17. The molecular action of the novel insecticide, Pyridalyl.

    PubMed

    Powell, Gerard F; Ward, Deborah A; Prescott, Mark C; Spiller, David G; White, Michael R H; Turner, Phillip C; Earley, Fergus G P; Phillips, Janet; Rees, Huw H

    2011-07-01

    Pyridalyl is a recently discovered insecticide that exhibits high insecticidal activity against Lepidoptera and Thysanoptera. Pyridalyl action requires cytochrome P450 activity, possibly for production of a bioactive derivative, Pyridalyl metabolism being prevented by general P450 inhibitors. Apoptosis is apparently not involved in the cytotoxicity. Continuous culture of Spodoptera frugiperda Sf21 cells in sub-lethal doses of Pyridalyl, results in a Pyridalyl-resistant cell line. Probing the molecular action of Pyridalyl by comparison of the proteomes of Pyridalyl-resistant and -susceptible cell lines, revealed differential expression of a number of proteins, including the up-regulation of thiol peroxiredoxin (TPx), in the resistant cells. Treatment of Bombyx mori larvae with Pyridalyl, followed by comparison of the midgut microsomal sub-proteome, revealed the up-regulation of three proteasome subunits. Such subunits, together with Hsp70 stress proteins, glyceraldehyde 3-phosphate dehydrogenases (GAPDHs) and thiol peroxiredoxin (TPx) were also up-regulated in the whole proteome of B. mori BM36 cells following treatment with the insecticide. The foregoing results lead to the hypothesis that cytochrome P450 action leads to an active Pyridalyl metabolite, which results in production of reactive oxygen species (ROS), that leads to damage to cellular macromolecules (e.g., proteins) and enhanced proteasome activity leads to increased protein degradation and necrotic cell death. PMID:21497652

  18. Colored Sticky Traps to Selectively Survey Thrips in Cowpea Ecosystem.

    PubMed

    Tang, L D; Zhao, H Y; Fu, B L; Han, Y; Liu, K; Wu, J H

    2016-02-01

    The bean flower thrips, Megalurothrips usitatus (Bagrall) (Thysanoptera: Thripidae), is an important pest of legume crops in South China. Yellow, blue, or white sticky traps are currently recommended for monitoring and controlling thrips, but it is not known whether one is more efficient than the other or if selectivity could be optimized by trap color. We investigated the response of thrips and beneficial insects to different-colored sticky traps on cowpea, Vigna unguiculata. More thrips were caught on blue, light blue, white, and purple traps than on yellow, green, pink, gray, red, or black traps. There was a weak correlation on the number of thrips caught on yellow traps and survey from flowers (r = 0.139), whereas a strong correlation was found for blue traps and thrips' survey on flowers (r = 0.929). On commercially available sticky traps (Jiaduo®), two and five times more thrips were caught on blue traps than on white and yellow traps, respectively. Otherwise, capture of beneficial insects was 1.7 times higher on yellow than on blue traps. The major natural enemies were the predatory ladybird beetles (63%) and pirate bugs Orius spp. (29%), followed by a number of less representative predators and parasitoids (8%). We conclude the blue sticky trap was the best to monitor thrips on cowpea in South China.

  19. The effect of latitudinal gradient on the species diversity of Chinese litter-dwelling thrips

    PubMed Central

    Wang, Jun; Tong, Xiaoli; Wu, Donghui

    2014-01-01

    Abstract To understand the global distribution patterns of litter-dwelling thrips, a total 150 leaf litter samples were collected from 6 natural reserves located in three climatic regions, temperate, subtropical and tropical. The results showed the relative abundance of Thysanoptera was over 3.0% in 4 natural reserves from subtropical and tropical zone, and reached 5.9% in one tropical reserve, only less than Acarina and Collembola. In contrast it was only 0.3% in the warm temperate natural reserves, and no thrips were collected in a mid temperate reserve. The order on the average species numbers per plot of litter thrips was tropic > subtropics > temperate (n=25, p<0.05). Mean density of litter thrips per plots in the tropics and subtropics was significantly higher than that in the temperate region (n=25, p<0.05), but the average density was not significantly different between tropical and subtropical zones (n=25, p>0.05). The diversity of litter thrips in the tropics and subtropics was much higher than that in the temperate area based on comparsions of Shannon-Wiener diversity index (H’), Pielou eveness index (J), and Simpson dominance index (D). All of these results indicated that litter-dwelling thrips lived mainly in tropical and subtropical regions; meanwhile, species number and relative abundance increased with decreasing latitude. PMID:25061351

  20. Occurrence of entomopathogenic fungi from agricultural and natural ecosystems in Saltillo, México, and their virulence towards thrips and whiteflies.

    PubMed

    Sánchez-Peña, Sergio R; Lara, Jorge San-Juan; Medina, Raúl F

    2011-01-01

    Entomopathogenic fungi were collected from soil in four adjacent habitats (oak forest, agricultural soil, pine reforestation and chaparral habitat) in Saltillo, México using the insect bait method with Tenebrio molitor (L.) (Coleoptera: Tenebrionidae) larvae as bait. Overall, of the larvae exposed to soil, 171 (20%) hosted Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), 25 (3%) hosted Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and 1 (0.1%) hosted lsaria (=Paecilomyces) sp. (Hypocreales: Cordycipitaceae). B. bassiana was significantly more frequent on larvae exposed to oak forest soil. M. anisopliae was significantly more frequent on larvae exposed to agricultural soil. From the infected bait insects, 93 isolates of B. bassiana and 24 isolates of M. anisopliae were obtained. Strains were tested for their infectivity against Cuban laurel thrips, Gynaikothrips uzeli Zimmerman (Thysanoptera: Phlaeothripidae) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae). B. bassiana isolates caused the highest mortality on thrips (some causing 88% mortality after 6 days); both fungal species caused similarly high mortality levels against whiteflies (75%) after 6 days. Large amounts of germplasm of entomopathogenic fungi, fundamentally B. bassiana and M. anisopliae, exist in the habitats sampled; pathogenicity varied among strains, and some strains possessed significant virulence. Soils in these habitats are reservoirs of diverse strains with potential for use in biocontrol. PMID:21521145

  1. Arthropods, plants, and transmission lines in Arizona: secondary succession in a Sonoran Desert habitat

    SciTech Connect

    Johnson, C.D.; Ditsworth, T.M.; Beley, J.R.

    1981-09-01

    Overall arthropod densities were low at this site, but the arthropod densities on the disturbed areas appeared to be enhanced after several years. No taxa were found to be statistically different in density between control and disturbed plots. Diversity decreased on the disturbed area after construction. Arthropod community similarity (C) was lower after construction, but C values appear to be related to presence or absence of annual herbs and grasses and not to total cover. Except for globe mallow, there were no pioneer plant species on the experimental plot. Effects of powerline construction on the experimental plant community were a brief reduction in total cover and a slight increase in cover of herbs and annual grasses. The 1976 and 1977 samples exhibit comparable cover values of these plants on both experimental and control plots. The dominant arthropod taxa on the experimental area (especially Thysanoptera, Cicadellidae, Coccinellidae, and Melyridae) appear to be responding numerically to the annual herbs and grasses which are becoming established on the plot.

  2. Two new species of Scirtothrips genus-group (Thripidae) of Northern Peninsular Malaysia.

    PubMed

    Ng, Y F; Mound, L A

    2016-01-01

    The survey of Thysanoptera in peninsular Malaysia has been concentrated largely in areas growing crops and flowers around Kuala Lumpur, and the Cameron Highlands, and there are few records of these insects from native forests particularly in the northern part of the country. The two species described here were collected during a recent visit to Belum-Temengor Forest Complex, in Perak State, part of the second largest forested area on the peninsular, and connected to the Bang Lang National Park, in Yala Province, Thailand. This forest has been well known as home to a number of endangered animals, including Malayan tigers and Asian elephants, as well as remarkable plant species such as Rafflesia with the world's largest flowers (Abdullah et al. 2011). Despite this, forest areas are facing a major challenge from the insatiable demand for timber, palm oil and minerals, with an 80% increase in deforestation rate in Malaysia between 1990 and 2005 (FAO 2010). Forested land in peninsular Malaysia has been estimated at 5.88 million-ha or 44% of total area, but the coverage of reserved virgin forest is about 0.40 % or 23,002-ha (Dahlan 2008). PMID:27394331

  3. Development of reference transcriptomes for the major field insect pests of cowpea: a toolbox for insect pest management approaches in west Africa.

    PubMed

    Agunbiade, Tolulope A; Sun, Weilin; Coates, Brad S; Djouaka, Rousseau; Tamò, Manuele; Ba, Malick N; Binso-Dabire, Clementine; Baoua, Ibrahim; Olds, Brett P; Pittendrigh, Barry R

    2013-01-01

    Cowpea is a widely cultivated and major nutritional source of protein for many people that live in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include the pod sucking bugs, Anoplocnemis curvipes Fabricius (Hemiptera: Coreidae) and Clavigralla tomentosicollis Stål (Hemiptera: Coreidae); as well as phloem-feeding cowpea aphids, Aphis craccivora Koch (Hemiptera: Aphididae) and flower thrips, Megalurothrips sjostedti Trybom (Thysanoptera: Thripidae). Efforts to control these pests remain a challenge and there is a need to understand the structure and movement of these pest populations in order to facilitate the development of integrated pest management strategies (IPM). Molecular tools have the potential to help facilitate a better understanding of pest populations. Towards this goal, we used 454 pyrosequencing technology to generate 319,126, 176,262, 320,722 and 227,882 raw reads from A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. The reads were de novo assembled into 11,687, 7,647, 10,652 and 7,348 transcripts for A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. Functional annotation of the resulting transcripts identified genes putatively involved in insecticide resistance, pathogen defense and immunity. Additionally, sequences that matched the primary aphid endosymbiont, Buchnera aphidicola, were identified among A. craccivora transcripts. Furthermore, 742, 97, 607 and 180 single nucleotide polymorphisms (SNPs) were respectively predicted among A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti transcripts, and will likely be valuable tools for future molecular genetic marker development. These results demonstrate that Roche 454-based transcriptome sequencing could be useful for the development of genomic resources for cowpea pest insects in West Africa. PMID:24278221

  4. Can mass trapping reduce thrips damage and is it economically viable? Management of the Western flower thrips in strawberry.

    PubMed

    Sampson, Clare; Kirk, William D J

    2013-01-01

    The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a cosmopolitan, polyphagous insect pest that causes bronzing to fruit of strawberry (Fragaria x ananassa). The main aim of this study was to test whether mass trapping could reduce damage and to predict whether this approach would be economically viable. In semi-protected strawberry crops, mass trapping of F. occidentalis using blue sticky roller traps reduced adult thrips numbers per flower by 61% and fruit bronzing by 55%. The addition of the F. occidentalis aggregation pheromone, neryl (S)-2-methylbutanoate, to the traps doubled the trap catch, reduced adult thrips numbers per flower by 73% and fruit bronzing by 68%. The factors affecting trapping efficiency through the season are discussed. Damage that would result in downgrading of fruit to a cheaper price occurred when bronzing affected about 10% of the red fruit surface. Cost-benefit analysis using this threshold showed that mass trapping of thrips using blue sticky roller traps can be cost-effective in high-value crops. The addition of blue sticky roller traps to an integrated pest management programme maintained thrips numbers below the damage threshold and increased grower returns by a conservative estimate of £2.2k per hectare. Further work is required to develop the F. occidentalis aggregation pheromone for mass trapping and to determine the best timing for trap deployment. Mass trapping of thrips is likely to be cost-effective in other countries and other high-value crops affected by F. occidentalis damage, such as cucumber and cut flowers. PMID:24282554

  5. Insect Herbivores Associated With Ludwigia Species, Oligospermum Section, in Their Argentine Distribution

    PubMed Central

    Hernández, M. Cristina; Cabrera Walsh, Guillermo

    2014-01-01

    The South American water primroses, Ludwigia grandiflora (Michx.) Greuter & Burdet, L. grandiflora subsp. hexapetala (Hook. & Arn.) G.L. Nesom & Kartesz, Ludwigia peploides (Kunth) P.H. Raven, and L. p. subsp. montevidensis (Spreng.) P.H. Raven (Onagraceae, Section Oligospermum), have become invasive in several watersheds of the United States and Europe. Surveys were carried out in center-east of Argentina to find insect species that might serve as biological control agents for L. g. subsp. hexapetala in California and elsewhere. Stems (0.5–0.6 m) of Ludwigia species, Sect. Oligospermum, were collected in 41 sites and analyzed in the laboratory; immature insects were reared to adults. The plant species found in the area were L. grandiflora (2 sites), L. g. subsp. hexapetala (33 sites), and L. p. subsp. montevidensis (4 sites). There was a variety of insect guilds feeding on L. g. subsp. hexapetala, including six species with stem-borer larvae, one species with fruit-feeding larvae, four species with defoliating larvae, two species with defoliating larvae on young leaves and axil meristems, one species of cell content feeder, and three species of sap feeders. Nine of these species also have defoliating adults. Biological information on most of them is provided. Of these insect herbivores, only two species were also found on L. grandiflora, and one on L. peploides. Several of the species found on L. g. hexapetala, such as the cell-content feeder Liothrips ludwigi (Thysanoptera), the stem-borers Merocnemus binotatus (Boheman) and Tyloderma spp. (Coleoptera), are promising candidates for biocontrol agents. PMID:25502037

  6. Primordial enemies: fungal pathogens in thrips societies.

    PubMed

    Turnbull, Christine; Wilson, Peter D; Hoggard, Stephen; Gillings, Michael; Palmer, Chris; Smith, Shannon; Beattie, Doug; Hussey, Sam; Stow, Adam; Beattie, Andrew

    2012-01-01

    Microbial pathogens are ancient selective agents that have driven many aspects of multicellular evolution, including genetic, behavioural, chemical and immune defence systems. It appears that fungi specialised to attack insects were already present in the environments in which social insects first evolved and we hypothesise that if the early stages of social evolution required antifungal defences, then covariance between levels of sociality and antifungal defences might be evident in extant lineages, the defences becoming stronger with group size and increasing social organisation. Thus, we compared the activity of cuticular antifungal compounds in thrips species (Insecta: Thysanoptera) representing a gradient of increasing group size and sociality: solitary, communal, social and eusocial, against the entomopathogen Cordyceps bassiana. Solitary and communal species showed little or no activity. In contrast, the social and eusocial species killed this fungus, suggesting that the evolution of sociality has been accompanied by sharp increases in the effectiveness of antifungal compounds. The antiquity of fungal entomopathogens, demonstrated by fossil finds, coupled with the unequivocal response of thrips colonies to them shown here, suggests two new insights into the evolution of thrips sociality: First, traits that enabled nascent colonies to defend themselves against microbial pathogens should be added to those considered essential for social evolution. Second, limits to the strength of antimicrobials, through resource constraints or self-antibiosis, may have been overcome by increase in the numbers of individuals secreting them, thus driving increases in colony size. If this is the case for social thrips, then we may ask: did antimicrobial traits and microbes such as fungal entomopathogens play an integral part in the evolution of insect sociality in general? PMID:23185420

  7. Economic Benefit for Cuban Laurel Thrips Biological Control.

    PubMed

    Shogren, C; Paine, T D

    2016-02-01

    The Cuban laurel thrips, Gynaikothrips ficorum Marchal (Thysanoptera: Phlaeothripidae), is a critical insect pest of Ficus microcarpa in California urban landscapes and production nurseries. Female thrips feed and oviposit on young Ficus leaves, causing the expanding leaves to fold or curl into a discolored leaf gall. There have been attempts to establish specialist predator natural enemies of the thrips, but no success has been reported. We resampled the same areas in 2013-2014 where we had released Montandoniola confusa (= morguesi) Streito and Matocq (Hemiptera: Anthocoridae) in southern California in 1995 but had been unable to recover individuals in 1997-1998. Thrips galls were significantly reduced in all three of the locations in the recent samples compared with the earlier samples. M. confusa was present in all locations and appears to be providing successful biological control. The value of the biological control, the difference between street trees in good foliage condition and trees with poor foliage, was $58,766,166. If thrips damage reduced the foliage to very poor condition, the value of biological control was $73,402,683. Total cost for the project was $61,830. The benefit accrued for every dollar spent on the biological control of the thrips ranged from $950, if the foliage was in poor condition, to $1,187, if the foliage was in very poor condition. The value of urban forest is often underappreciated. Economic analyses that clearly demonstrate the very substantial rates of return on investment in successful biological control in urban forests provide compelling arguments for supporting future efforts.

  8. Thrips Settling, Oviposition and IYSV Distribution on Onion Foliage.

    PubMed

    Chitturi, Anitha; Riley, David; Nischwitz, Claudia; Gitaitis, Ron; Srinivasan, Rajagopalbabu

    2015-06-01

    Thrips tabaci Lindeman (Thysanoptera: Thripidae) adult and larval settling and oviposition on onion (Allium cepa L.) foliage were investigated in relation to leaf position and leaf length at prebulb plant growth stages under controlled conditions. In the laboratory, four and six adult females of T. tabaci were released on onion plants at three-leaf stage and six- to eight-leaf stage, respectively, and thrips egg, nymph, and adult count data were collected on each of the three inner most leaves at every 2-cm leaf segment. Thrips settling and oviposition parameters were quantified during the light period on the above ground portion of onion plants from the distal end of the bulb or leaf sheath "neck" through the tips of the foliage. Results from studies confirmed that distribution of thrips adults, nymphs, and eggs were skewed toward the base of the plant. The settling distributions of thrips adults and nymphs differed slightly from the egg distribution in that oviposition occurred all the way to the tip of the leaf while adults and nymphs were typically not observed near the tip. In a field study, the foliage was divided into three equal partitions, i.e., top, middle, basal thirds, and thrips adults by species, primarily Frankliniella fusca (Hinds) and T. tabaci, were collected from each partition to determine if there was a similar bias of all adult thrips toward the base of the plant. The results suggested that adults of different species appear to segregate along leaf length. Finally, thrips oviposition on 2-cm segments and Iris yellow spot virus positive leaf segments were quantified in the field, irrespective of thrips species. Both variables demonstrated a very similar pattern of bias toward the base of the plant and were significantly correlated. PMID:26470242

  9. Dynamics of the leaf-litter arthropod fauna following fire in a neotropical woodland savanna.

    PubMed

    Vasconcelos, Heraldo L; Pacheco, Renata; Silva, Raphael C; Vasconcelos, Pedro B; Lopes, Cauê T; Costa, Alan N; Bruna, Emilio M

    2009-11-09

    Fire is an important agent of disturbance in tropical savannas, but relatively few studies have analyzed how soil-and-litter dwelling arthropods respond to fire disturbance despite the critical role these organisms play in nutrient cycling and other biogeochemical processes. Following the incursion of a fire into a woodland savanna ecological reserve in Central Brazil, we monitored the dynamics of litter-arthropod populations for nearly two years in one burned and one unburned area of the reserve. We also performed a reciprocal transplant experiment to determine the effects of fire and litter type on the dynamics of litter colonization by arthropods. Overall arthropod abundance, the abundance of individual taxa, the richness of taxonomic groups, and the species richness of individual taxa (Formiciade) were lower in the burned site. However, both the ordinal-level composition of the litter arthropod fauna and the species-level composition of the litter ant fauna were not dramatically different in the burned and unburned sites. There is evidence that seasonality of rainfall interacts with fire, as differences in arthropod abundance and diversity were more pronounced in the dry than in the wet season. For many taxa the differences in abundance between burned and unburned sites were maintained even when controlling for litter availability and quality. In contrast, differences in abundance for Collembola, Formicidae, and Thysanoptera were only detected in the unmanipulated samples, which had a lower amount of litter in the burned than in the unburned site throughout most of our study period. Together these results suggest that arthropod density declines in fire-disturbed areas as a result of direct mortality, diminished resources (i.e., reduced litter cover) and less favorable microclimate (i.e., increased litter desiccation due to reduction in tree cover). Although these effects were transitory, there is evidence that the increasingly prevalent fire return interval of

  10. Thrips domiciles protect larvae from desiccation in an arid environment.

    PubMed

    Gilbert, James D J

    2014-11-01

    Desiccation is a particular risk for small animals in arid environments. In response, many organisms "construct niches," favorable microenvironments where they spend part or all of their life cycle. Some maintain such environments for their offspring via parental care. Insect eggs are often protected from desiccation by parentally derived gels, casings, or cocoons, but active parental protection of offspring from desiccation has never been demonstrated. Most free-living thrips (Thysanoptera) alleviate water loss via thigmotaxis (crevice seeking). In arid Australia, Acacia thrips (Phlaeothripidae) construct many kinds of niche. Some thrips induce galls; others, like Dunatothrips aneurae, live and breed within "domiciles" made from loosely glued phyllodes. The function of domiciles is unknown; like other constructed niches, they may 1) create favorable microenvironments, 2) facilitate feeding, 3) protect from enemies, or a combination. To test the first 2 alternatives experimentally, field-collected domiciles were destroyed or left intact. Seven-day survival of feeding and nonfeeding larval stages was monitored at high (70-80%) or low (8-10%, approximately ambient) humidity. Regardless of humidity, most individuals survived in intact domiciles, whereas for destroyed domiciles, survival depended on humidity, suggesting parents construct and maintain domiciles to prevent offspring desiccating. Feeding and nonfeeding larvae had similar survival patterns, suggesting the domicile's role is not nutritional. Outside domiciles, survival at "high" humidity was intermediate, suggesting very high humidity requirements, or energetic costs of wandering outside domiciles. D. aneurae commonly cofound domiciles; cofoundresses may benefit both from shared nestbuilding costs, and from "deferred byproduct mutualism," that is, backup parental care in case of mortality.

  11. Neither insects nor wind: ambophily in dioecious Chamaedorea palms (Arecaceae).

    PubMed

    Rios, L D; Fuchs, E J; Hodel, D R; Cascante-Marín, A

    2014-07-01

    Pollination of Neotropical dioecious trees is commonly related to generalist insects. Similar data for non-tree species with separated genders are inconclusive. Recent studies on pollination of dioecious Chamaedorea palms (Arecaceae) suggest that species are either insect- or wind-pollinated. However, the wide variety of inflorescence and floral attributes within the genus suggests mixed pollination mode involving entomophily and anemophily. To evaluate this hypothesis, we studied the pollination of Chamaedorea costaricana, C. macrospadix, C. pinnatifrons and C. tepejilote in two montane forests in Costa Rica. A complementary morphological analysis of floral traits was carried out to distinguish species groups within the genus according to their most probable pollination mechanism. We conducted pollinator exclusion experiments, field observations on visitors to pistillate and staminate inflorescences, and trapped airborne pollen. A cluster analysis using 18 floral traits selected for their association with wind and insect pollination syndromes was carried out using 52 Chamaedorea species. Exclusion experiments showed that both wind and insects, mostly thrips (Thysanoptera), pollinated the studied species. Thrips used staminate inflorescences as brood sites and pollinated pistillate flowers by deception. Insects caught on pistillate inflorescences transported pollen, while traps proved that pollen is wind-borne. Our empirical findings clearly suggest that pollination of dioecious Chamaedorea palms is likely to involve both insects and wind. A cluster analysis showed that the majority of studied species have a combination of floral traits that allow for both pollination modes. Our pollination experiments and morphological analysis both suggest that while some species may be completely entomophilous or anemophilous, ambophily might be a common condition within Chamaedorea. Our results propose a higher diversity of pollination mechanisms of Neotropical dioecious

  12. Insecticidal properties of a Chenopodium-based botanical.

    PubMed

    Chiasson, H; Vincent, C; Bostanian, N J

    2004-08-01

    The emulsifiable concentrate UDA-245 based on an essential oil extract from Chenopodium ambrosioides variety near ambrosioides, a North American herbaceous plant, was compared with commercially available pesticides for their effectiveness to control green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae), western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and greenhouse whitefly, Trialeurodes vaporariorium (Westwood) (Homoptera: Aleyrodidae). Side effects on the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) also were determined. With green peach aphid, UDA-245 at 0.5% concentration was significantly more effective than the control (water) treatment in a laboratory bioassay and significantly more effective than neem oil and the control treatment and as effective as insecticidal soap in a greenhouse assay. With the western flower thrips, UDA-245 at 0.5% was significantly more effective than neem oil, insecticidal soap and the control treatment in a laboratory bioassay, whereas in a greenhouse assay, UDA-245 at 1.0% was the only treatment that maintained control of the western flower thrips 2 wk after the last treatment period. UDA-245 at 0.5% (laboratory bioassay) was significantly more effective in managing greenhouse whitefly than neem oil, endosulfan, and the control treatment and as effective as insecticidal soap. Insecticidal soap proved to be toxic to the parasitoid E. formosa (71.9% mortality), whereas UDA-245 at 0.5% was not significantly more toxic than the control (11.2 and 4.6% mortality, respectively). Our results suggest that a greenhouse integrated pest management (IPM) program using a botanical such as UDA-245 could effectively control infestations of major pests present while having a negligible effect on biological control agents.

  13. Variation within and between Frankliniella thrips species in host plant utilization.

    PubMed

    Baez, Ignacio; Reitz, Stuart R; Funderburk, Joseph E; Olson, Steve M

    2011-01-01

    Anthophilous flower thrips in the genus Frankliniella (Thysanoptera: Thripidae) exploit ephemeral plant resources and therefore must be capable of successfully locating appropriate hosts on a repeated basis, yet little is known of interspecific and intraspecific variation in responses to host plant type and nutritional quality. Field trials were conducted over two seasons to determine if the abundance of males and females of three common Frankliniella species, F. occidentalis (Pergande), F. tritici (Fitch) and F. bispinosa (Morgan), their larvae, and a key predator, Orius insidiosus (Say) (Hemiptera: Anthocoridae) were affected by host plant type and plant nutritional quality. Two host plants, pepper, Capsicum annuum L. (Solanales: Solanaceae) and tomato, Solanum lycopersicum L. that vary in suitability for these species were examined, and their nutritional quality was manipulated by applying three levels of nitrogen fertilization (101 kg/ha, 202 kg/ha, 404 kg/ha). F. occidentalis females were more abundant in pepper than in tomato, but males did not show a differential response. Both sexes of F. tritici and F. bispinosa were more abundant in tomato than in pepper. Larval thrips were more abundant in pepper than in tomato. Likewise, O. insidiosus females and nymphs were more abundant in pepper than in tomato. Only F. occidentalis females showed a distinct response to nitrogen fertilization, with abundance increasing with fertilization. These results show that host plant utilization patterns vary among Frankliniella spp. and should not be generalized from results of the intensively studied F. occidentalis. Given the different pest status of these species and their differential abundance in pepper and tomato, it is critical that scouting programs include species identifications for proper management. PMID:21539418

  14. Neither insects nor wind: ambophily in dioecious Chamaedorea palms (Arecaceae).

    PubMed

    Rios, L D; Fuchs, E J; Hodel, D R; Cascante-Marín, A

    2014-07-01

    Pollination of Neotropical dioecious trees is commonly related to generalist insects. Similar data for non-tree species with separated genders are inconclusive. Recent studies on pollination of dioecious Chamaedorea palms (Arecaceae) suggest that species are either insect- or wind-pollinated. However, the wide variety of inflorescence and floral attributes within the genus suggests mixed pollination mode involving entomophily and anemophily. To evaluate this hypothesis, we studied the pollination of Chamaedorea costaricana, C. macrospadix, C. pinnatifrons and C. tepejilote in two montane forests in Costa Rica. A complementary morphological analysis of floral traits was carried out to distinguish species groups within the genus according to their most probable pollination mechanism. We conducted pollinator exclusion experiments, field observations on visitors to pistillate and staminate inflorescences, and trapped airborne pollen. A cluster analysis using 18 floral traits selected for their association with wind and insect pollination syndromes was carried out using 52 Chamaedorea species. Exclusion experiments showed that both wind and insects, mostly thrips (Thysanoptera), pollinated the studied species. Thrips used staminate inflorescences as brood sites and pollinated pistillate flowers by deception. Insects caught on pistillate inflorescences transported pollen, while traps proved that pollen is wind-borne. Our empirical findings clearly suggest that pollination of dioecious Chamaedorea palms is likely to involve both insects and wind. A cluster analysis showed that the majority of studied species have a combination of floral traits that allow for both pollination modes. Our pollination experiments and morphological analysis both suggest that while some species may be completely entomophilous or anemophilous, ambophily might be a common condition within Chamaedorea. Our results propose a higher diversity of pollination mechanisms of Neotropical dioecious

  15. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting?

    PubMed Central

    Spafford, Ryan D; Lortie, Christopher J

    2013-01-01

    Arthropods are critical ecosystem components due to their high diversity and sensitivity to perturbation. Furthermore, due to their ease of capture they are often the focus of environmental health surveys. There is much debate regarding the best sampling method to use in these surveys. Sweep netting and pan trapping are two sampling methods commonly used in agricultural arthropod surveys, but have not been contrasted in natural grassland systems at the community level. The purpose of this study was to determine whether sweep netting was effective at estimating arthropod diversity at the community level in grasslands or if supplemental pan trapping was needed. Arthropods were collected from grassland sites in Montana, USA, in the summer of 2011. The following three standardized evaluation criteria (consistency, reliability, and precision) were developed to assess the efficacy of sweep netting and pan trapping, based on analyses of variations in arthropod abundances, species richness, evenness, capture frequency, and community composition. Neither sampling method was sufficient in any criteria to be used alone for community-level arthropod surveys. On a taxa-specific basis, however, sweep netting was consistent, reliable, and precise for Thysanoptera, infrequently collected (i.e., rare) insects, and Arachnida, whereas pan trapping was consistent, reliable, and precise for Collembola and bees, which is especially significant given current threats to the latter's populations worldwide. Species-level identifications increase the detected dissimilarity between sweep netting and pan trapping. We recommend that community-level arthropod surveys use both sampling methods concurrently, at least in grasslands, but likely in most nonagricultural systems. Target surveys, such as monitoring bee communities in fragmented grassland habitat or where detailed information on behavior of the target arthropod groups is available can in some instances employ singular methods. As a

  16. How Predictable Are the Behavioral Responses of Insects to Herbivore Induced Changes in Plants? Responses of Two Congeneric Thrips to Induced Cotton Plants

    PubMed Central

    Silva, Rehan; Furlong, Michael J.; Wilson, Lewis J.; Walter, Gimme H.

    2013-01-01

    Changes in plants following insect attack are referred to as induced responses. These responses are widely viewed as a form of defence against further insect attack. In the current study we explore whether it is possible to make generalizations about induced plant responses given the unpredictability and variability observed in insect-plant interactions. Experiments were conducted to test for consistency in the responses of two congeneric thrips, Frankliniella schultzei Trybom and Frankliniella occidentalis Pergrande (Thysanoptera: Thripidae) to cotton seedlings (Gossypium hirsutum Linneaus (Malvales: Malvaceae)) damaged by various insect herbivores. In dual-choice experiments that compared intact and damaged cotton seedlings, F. schultzei was attracted to seedlings damaged by Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), Tetranychus urticae (Koch) (Trombidiforms: Tetranychidae), Tenebrio molitor Linnaeus (Coleoptera: Tenebrionidae), F. schultzei and F. occidentalis but not to mechanically damaged seedlings. In similar tests, F. occidentalis was attracted to undamaged cotton seedlings when simultaneously exposed to seedlings damaged by H. armigera, T. molitor or F. occidentalis. However, when exposed to F. schultzei or T. urticae damaged plants, F. occidentalis was more attracted towards damaged plants. A quantitative relationship was also apparent, F. schultzei showed increased attraction to damaged seedlings as the density of T. urticae or F. schultzei increased. In contrast, although F. occidentalis demonstrated increased attraction to plants damaged by higher densities of T. urticae, there was a negative relationship between attraction and the density of damaging conspecifics. Both species showed greater attraction to T. urticae damaged seedlings than to seedlings damaged by conspecifics. Results demonstrate that the responses of both species of thrips were context dependent, making generalizations difficult to formulate. PMID:23691075

  17. Insecticidal properties of a Chenopodium-based botanical.

    PubMed

    Chiasson, H; Vincent, C; Bostanian, N J

    2004-08-01

    The emulsifiable concentrate UDA-245 based on an essential oil extract from Chenopodium ambrosioides variety near ambrosioides, a North American herbaceous plant, was compared with commercially available pesticides for their effectiveness to control green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae), western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), and greenhouse whitefly, Trialeurodes vaporariorium (Westwood) (Homoptera: Aleyrodidae). Side effects on the whitefly parasitoid Encarsia formosa Gahan (Hymenoptera: Aphelinidae) also were determined. With green peach aphid, UDA-245 at 0.5% concentration was significantly more effective than the control (water) treatment in a laboratory bioassay and significantly more effective than neem oil and the control treatment and as effective as insecticidal soap in a greenhouse assay. With the western flower thrips, UDA-245 at 0.5% was significantly more effective than neem oil, insecticidal soap and the control treatment in a laboratory bioassay, whereas in a greenhouse assay, UDA-245 at 1.0% was the only treatment that maintained control of the western flower thrips 2 wk after the last treatment period. UDA-245 at 0.5% (laboratory bioassay) was significantly more effective in managing greenhouse whitefly than neem oil, endosulfan, and the control treatment and as effective as insecticidal soap. Insecticidal soap proved to be toxic to the parasitoid E. formosa (71.9% mortality), whereas UDA-245 at 0.5% was not significantly more toxic than the control (11.2 and 4.6% mortality, respectively). Our results suggest that a greenhouse integrated pest management (IPM) program using a botanical such as UDA-245 could effectively control infestations of major pests present while having a negligible effect on biological control agents. PMID:15384351

  18. Development of Reference Transcriptomes for the Major Field Insect Pests of Cowpea: A Toolbox for Insect Pest Management Approaches in West Africa

    PubMed Central

    Agunbiade, Tolulope A.; Sun, Weilin; Coates, Brad S.; Djouaka, Rousseau; Tamò, Manuele; Ba, Malick N.; Binso-Dabire, Clementine; Baoua, Ibrahim; Olds, Brett P.; Pittendrigh, Barry R.

    2013-01-01

    Cowpea is a widely cultivated and major nutritional source of protein for many people that live in West Africa. Annual yields and longevity of grain storage is greatly reduced by feeding damage caused by a complex of insect pests that include the pod sucking bugs, Anoplocnemis curvipes Fabricius (Hemiptera: Coreidae) and Clavigralla tomentosicollis Stål (Hemiptera: Coreidae); as well as phloem-feeding cowpea aphids, Aphis craccivora Koch (Hemiptera: Aphididae) and flower thrips, Megalurothrips sjostedti Trybom (Thysanoptera: Thripidae). Efforts to control these pests remain a challenge and there is a need to understand the structure and movement of these pest populations in order to facilitate the development of integrated pest management strategies (IPM). Molecular tools have the potential to help facilitate a better understanding of pest populations. Towards this goal, we used 454 pyrosequencing technology to generate 319,126, 176,262, 320,722 and 227,882 raw reads from A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. The reads were de novo assembled into 11,687, 7,647, 10,652 and 7,348 transcripts for A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti, respectively. Functional annotation of the resulting transcripts identified genes putatively involved in insecticide resistance, pathogen defense and immunity. Additionally, sequences that matched the primary aphid endosymbiont, Buchnera aphidicola, were identified among A. craccivora transcripts. Furthermore, 742, 97, 607 and 180 single nucleotide polymorphisms (SNPs) were respectively predicted among A. curvipes, A. craccivora, C. tomentosicollis and M. sjostedti transcripts, and will likely be valuable tools for future molecular genetic marker development. These results demonstrate that Roche 454-based transcriptome sequencing could be useful for the development of genomic resources for cowpea pest insects in West Africa. PMID:24278221

  19. Invasion Genetics of the Western Flower Thrips in China: Evidence for Genetic Bottleneck, Hybridization and Bridgehead Effect

    PubMed Central

    Yang, Xian-Ming; Sun, Jing-Tao; Xue, Xiao-Feng; Li, Jin-Bo; Hong, Xiao-Yue

    2012-01-01

    The western flower thrips, Frankliniella occidentalis (Pergande), is an invasive species and the most economically important pest within the insect order Thysanoptera. F. occidentalis, which is endemic to North America, was initially detected in Kunming in southwestern China in 2000 and since then it has rapidly invaded several other localities in China where it has greatly damaged greenhouse vegetables and ornamental crops. Controlling this invasive pest in China requires an understanding of its genetic makeup and migration patterns. Using the mitochondrial COI gene and 10 microsatellites, eight of which were newly isolated and are highly polymorphic, we investigated the genetic structure and the routes of range expansion of 14 F. occidentalis populations in China. Both the mitochondrial and microsatellite data revealed that the genetic diversity of F. occidentalis of the Chinese populations is lower than that in its native range. Two previously reported cryptic species (or ecotypes) were found in the study. The divergence in the mitochondrial COI of two Chinese cryptic species (or ecotypes) was about 3.3% but they cannot be distinguished by nuclear markers. Hybridization might produce such substantial mitochondrial-nuclear discordance. Furthermore, we found low genetic differentiation (global FST = 0.043, P<0.001) among all the populations and strong evidence for gene flow, especially from the three southwestern populations (Baoshan, Dali and Kunming) to the other Chinese populations. The directional gene flow was further supported by the higher genetic diversity of these three southwestern populations. Thus, quarantine and management of F. occidentalis should focus on preventing it from spreading from the putative source populations to other parts of China. PMID:22509325

  20. Thrips Settling, Oviposition and IYSV Distribution on Onion Foliage.

    PubMed

    Chitturi, Anitha; Riley, David; Nischwitz, Claudia; Gitaitis, Ron; Srinivasan, Rajagopalbabu

    2015-06-01

    Thrips tabaci Lindeman (Thysanoptera: Thripidae) adult and larval settling and oviposition on onion (Allium cepa L.) foliage were investigated in relation to leaf position and leaf length at prebulb plant growth stages under controlled conditions. In the laboratory, four and six adult females of T. tabaci were released on onion plants at three-leaf stage and six- to eight-leaf stage, respectively, and thrips egg, nymph, and adult count data were collected on each of the three inner most leaves at every 2-cm leaf segment. Thrips settling and oviposition parameters were quantified during the light period on the above ground portion of onion plants from the distal end of the bulb or leaf sheath "neck" through the tips of the foliage. Results from studies confirmed that distribution of thrips adults, nymphs, and eggs were skewed toward the base of the plant. The settling distributions of thrips adults and nymphs differed slightly from the egg distribution in that oviposition occurred all the way to the tip of the leaf while adults and nymphs were typically not observed near the tip. In a field study, the foliage was divided into three equal partitions, i.e., top, middle, basal thirds, and thrips adults by species, primarily Frankliniella fusca (Hinds) and T. tabaci, were collected from each partition to determine if there was a similar bias of all adult thrips toward the base of the plant. The results suggested that adults of different species appear to segregate along leaf length. Finally, thrips oviposition on 2-cm segments and Iris yellow spot virus positive leaf segments were quantified in the field, irrespective of thrips species. Both variables demonstrated a very similar pattern of bias toward the base of the plant and were significantly correlated.

  1. Can Mass Trapping Reduce Thrips Damage and Is It Economically Viable? Management of the Western Flower Thrips in Strawberry

    PubMed Central

    Sampson, Clare; Kirk, William D. J.

    2013-01-01

    The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a cosmopolitan, polyphagous insect pest that causes bronzing to fruit of strawberry (Fragaria x ananassa). The main aim of this study was to test whether mass trapping could reduce damage and to predict whether this approach would be economically viable. In semi-protected strawberry crops, mass trapping of F. occidentalis using blue sticky roller traps reduced adult thrips numbers per flower by 61% and fruit bronzing by 55%. The addition of the F. occidentalis aggregation pheromone, neryl (S)-2-methylbutanoate, to the traps doubled the trap catch, reduced adult thrips numbers per flower by 73% and fruit bronzing by 68%. The factors affecting trapping efficiency through the season are discussed. Damage that would result in downgrading of fruit to a cheaper price occurred when bronzing affected about 10% of the red fruit surface. Cost-benefit analysis using this threshold showed that mass trapping of thrips using blue sticky roller traps can be cost-effective in high-value crops. The addition of blue sticky roller traps to an integrated pest management programme maintained thrips numbers below the damage threshold and increased grower returns by a conservative estimate of £2.2k per hectare. Further work is required to develop the F. occidentalis aggregation pheromone for mass trapping and to determine the best timing for trap deployment. Mass trapping of thrips is likely to be cost-effective in other countries and other high-value crops affected by F. occidentalis damage, such as cucumber and cut flowers. PMID:24282554

  2. Silicon reduces impact of plant nitrogen in promoting stalk borer (Eldana saccharina) but not sugarcane thrips (Fulmekiola serrata) infestations in sugarcane

    PubMed Central

    Keeping, Malcolm G.; Miles, Neil; Sewpersad, Chandini

    2014-01-01

    The stalk borer Eldana saccharina Walker (Lepidoptera: Pyralidae) is a major limiting factor in South African sugarcane production, while yield is also reduced by sugarcane thrips Fulmekiola serrata Kobus (Thysanoptera: Thripidae). Borer management options include appropriate nitrogen (N) and enhanced silicon (Si) nutrition; the effect of N on sugarcane thrips is unknown. We tested the effects of these nutrients, in combination with resistant (N33) and susceptible (N27) sugarcane cultivars, on E. saccharina and F. serrata infestation. Two pot trials with three levels of N (60, 120, and 180 kg ha-1) and two levels each of calcium silicate and dolomitic lime (5 and 10 t ha-1) were naturally infested with thrips, then artificially water stressed and infested with borer. Higher N levels increased borer survival and stalk damage, while Si reduced these compared with controls. Silicon significantly reduced stalk damage in N27 but not in N33; hence, Si provided relatively greater protection for susceptible cultivars than for resistant ones. High N treatments were associated with greater thrips numbers, while Si treatments did not significantly influence thrips infestation. The reduction in borer survival and stalk damage by Si application at all N rates indicates that under field conditions, the opportunity exists for optimizing sugarcane yields through maintaining adequate N nutrition, while reducing populations of E. saccharina using integrated pest management (IPM) tactics that include improved Si nutrition of the crop and reduced plant water stress. Improved management of N nutrition may also provide an option for thrips IPM. The contrasting effects of Si on stalk borer and thrips indicate that Si-mediated resistance to insect herbivores in sugarcane has mechanical and biochemical components that are well developed in the stalk tissues targeted by E. saccharina but poorly developed in the young leaf spindles where F. serrata occurs. PMID:24999349

  3. Dynamics of the Leaf-Litter Arthropod Fauna Following Fire in a Neotropical Woodland Savanna

    PubMed Central

    Vasconcelos, Heraldo L.; Pacheco, Renata; Silva, Raphael C.; Vasconcelos, Pedro B.; Lopes, Cauê T.; Costa, Alan N.; Bruna, Emilio M.

    2009-01-01

    Fire is an important agent of disturbance in tropical savannas, but relatively few studies have analyzed how soil-and-litter dwelling arthropods respond to fire disturbance despite the critical role these organisms play in nutrient cycling and other biogeochemical processes. Following the incursion of a fire into a woodland savanna ecological reserve in Central Brazil, we monitored the dynamics of litter-arthropod populations for nearly two years in one burned and one unburned area of the reserve. We also performed a reciprocal transplant experiment to determine the effects of fire and litter type on the dynamics of litter colonization by arthropods. Overall arthropod abundance, the abundance of individual taxa, the richness of taxonomic groups, and the species richness of individual taxa (Formiciade) were lower in the burned site. However, both the ordinal-level composition of the litter arthropod fauna and the species-level composition of the litter ant fauna were not dramatically different in the burned and unburned sites. There is evidence that seasonality of rainfall interacts with fire, as differences in arthropod abundance and diversity were more pronounced in the dry than in the wet season. For many taxa the differences in abundance between burned and unburned sites were maintained even when controlling for litter availability and quality. In contrast, differences in abundance for Collembola, Formicidae, and Thysanoptera were only detected in the unmanipulated samples, which had a lower amount of litter in the burned than in the unburned site throughout most of our study period. Together these results suggest that arthropod density declines in fire-disturbed areas as a result of direct mortality, diminished resources (i.e., reduced litter cover) and less favorable microclimate (i.e., increased litter desiccation due to reduction in tree cover). Although these effects were transitory, there is evidence that the increasingly prevalent fire return interval of

  4. Thrips domiciles protect larvae from desiccation in an arid environment

    PubMed Central

    2014-01-01

    Desiccation is a particular risk for small animals in arid environments. In response, many organisms “construct niches,” favorable microenvironments where they spend part or all of their life cycle. Some maintain such environments for their offspring via parental care. Insect eggs are often protected from desiccation by parentally derived gels, casings, or cocoons, but active parental protection of offspring from desiccation has never been demonstrated. Most free-living thrips (Thysanoptera) alleviate water loss via thigmotaxis (crevice seeking). In arid Australia, Acacia thrips (Phlaeothripidae) construct many kinds of niche. Some thrips induce galls; others, like Dunatothrips aneurae, live and breed within “domiciles” made from loosely glued phyllodes. The function of domiciles is unknown; like other constructed niches, they may 1) create favorable microenvironments, 2) facilitate feeding, 3) protect from enemies, or a combination. To test the first 2 alternatives experimentally, field-collected domiciles were destroyed or left intact. Seven-day survival of feeding and nonfeeding larval stages was monitored at high (70–80%) or low (8–10%, approximately ambient) humidity. Regardless of humidity, most individuals survived in intact domiciles, whereas for destroyed domiciles, survival depended on humidity, suggesting parents construct and maintain domiciles to prevent offspring desiccating. Feeding and nonfeeding larvae had similar survival patterns, suggesting the domicile’s role is not nutritional. Outside domiciles, survival at “high” humidity was intermediate, suggesting very high humidity requirements, or energetic costs of wandering outside domiciles. D. aneurae commonly cofound domiciles; cofoundresses may benefit both from shared nestbuilding costs, and from “deferred byproduct mutualism,” that is, backup parental care in case of mortality. PMID:25419084

  5. Can mass trapping reduce thrips damage and is it economically viable? Management of the Western flower thrips in strawberry.

    PubMed

    Sampson, Clare; Kirk, William D J

    2013-01-01

    The western flower thrips Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a cosmopolitan, polyphagous insect pest that causes bronzing to fruit of strawberry (Fragaria x ananassa). The main aim of this study was to test whether mass trapping could reduce damage and to predict whether this approach would be economically viable. In semi-protected strawberry crops, mass trapping of F. occidentalis using blue sticky roller traps reduced adult thrips numbers per flower by 61% and fruit bronzing by 55%. The addition of the F. occidentalis aggregation pheromone, neryl (S)-2-methylbutanoate, to the traps doubled the trap catch, reduced adult thrips numbers per flower by 73% and fruit bronzing by 68%. The factors affecting trapping efficiency through the season are discussed. Damage that would result in downgrading of fruit to a cheaper price occurred when bronzing affected about 10% of the red fruit surface. Cost-benefit analysis using this threshold showed that mass trapping of thrips using blue sticky roller traps can be cost-effective in high-value crops. The addition of blue sticky roller traps to an integrated pest management programme maintained thrips numbers below the damage threshold and increased grower returns by a conservative estimate of £2.2k per hectare. Further work is required to develop the F. occidentalis aggregation pheromone for mass trapping and to determine the best timing for trap deployment. Mass trapping of thrips is likely to be cost-effective in other countries and other high-value crops affected by F. occidentalis damage, such as cucumber and cut flowers.

  6. Sweeping beauty: is grassland arthropod community composition effectively estimated by sweep netting?

    PubMed

    Spafford, Ryan D; Lortie, Christopher J

    2013-09-01

    Arthropods are critical ecosystem components due to their high diversity and sensitivity to perturbation. Furthermore, due to their ease of capture they are often the focus of environmental health surveys. There is much debate regarding the best sampling method to use in these surveys. Sweep netting and pan trapping are two sampling methods commonly used in agricultural arthropod surveys, but have not been contrasted in natural grassland systems at the community level. The purpose of this study was to determine whether sweep netting was effective at estimating arthropod diversity at the community level in grasslands or if supplemental pan trapping was needed. Arthropods were collected from grassland sites in Montana, USA, in the summer of 2011. The following three standardized evaluation criteria (consistency, reliability, and precision) were developed to assess the efficacy of sweep netting and pan trapping, based on analyses of variations in arthropod abundances, species richness, evenness, capture frequency, and community composition. Neither sampling method was sufficient in any criteria to be used alone for community-level arthropod surveys. On a taxa-specific basis, however, sweep netting was consistent, reliable, and precise for Thysanoptera, infrequently collected (i.e., rare) insects, and Arachnida, whereas pan trapping was consistent, reliable, and precise for Collembola and bees, which is especially significant given current threats to the latter's populations worldwide. Species-level identifications increase the detected dissimilarity between sweep netting and pan trapping. We recommend that community-level arthropod surveys use both sampling methods concurrently, at least in grasslands, but likely in most nonagricultural systems. Target surveys, such as monitoring bee communities in fragmented grassland habitat or where detailed information on behavior of the target arthropod groups is available can in some instances employ singular methods. As a

  7. Hyperspectral sensors and the conservation of monumental buildings

    NASA Astrophysics Data System (ADS)

    Camaiti, Mara; Benvenuti, Marco; Chiarantini, Leandro; Costagliola, Pilar; Moretti, Sandro; Paba, Francesca; Pecchioni, Elena; Vettori, Silvia

    2010-05-01

    -FieldSpec FP Pro spectroradiometer), which continuously acquires punctual reflectance spectra in the range 350-2500 nm, both in natural light conditions and by a contact probe (fixed geometry of shot). This instrument is used on field for the identification of different materials, as well as for the definition of maps (e.g geological maps) if coupled with other hyperspectral instruments. 2) Hyperspectral sensor SIM-GA (Selex Galileo Multisensor Hyperspectral System), a system with spatial acquisition of data which may be used on an earth as well as on an airborne platform. SIM-GA consists of two electro-optical heads, which operate in the VNIR and SWIR regions, respectively, between 400-1000 nm and 1000-2500 nm (3). Although the spectral signature in the VNIR of many minerals is known, the co-presence of more minerals on a surface can affect the quantitative analysis of gypsum. Different minerals, such as gypsum, calcite, weddellite, whewellite, and other components (i.e. carbon particles in black crusts) are, in fact, commonly found on historical surfaces. In order to illustrate the complexity, but also the potentiality of hyperspectral sensors (portable or remote sensing) for the characterization of stone surfaces, a case study, the Facade of Santa Maria Novella in Florence - Italy, will be presented. References 1) R.N. Clark and G.A. Swayze, 1995, "Mapping minerals, amorphous materials, environmental materials, vegetation, water, ice, and snow, and other materials: The USGS Tricorder Algorithm", in "Summaries of the Fifth Annual JPL Airborne Earth Science Workshop", JPL Publication 95-1,1,39-40 2) E. Ben-Dor, K. Patin, A. Banin and A. Karnieli, 2002, "Mapping of several soil properties using DATS-7915 hyperspectral scanner data. A case study over clayely soils in Israel", International Journal of Remote Sensing, 23(6), 1043-1062 3) S. Vettori, M. Benvenuti, M. Camaiti, L. Chiarantini, P. Costagliola, S. Moretti, E. Pecchioni, 2008, "Assessment of the deterioration status of

  8. Hyperspectral sensors and the conservation of monumental buildings

    NASA Astrophysics Data System (ADS)

    Camaiti, Mara; Benvenuti, Marco; Chiarantini, Leandro; Costagliola, Pilar; Moretti, Sandro; Paba, Francesca; Pecchioni, Elena; Vettori, Silvia

    2010-05-01

    -FieldSpec FP Pro spectroradiometer), which continuously acquires punctual reflectance spectra in the range 350-2500 nm, both in natural light conditions and by a contact probe (fixed geometry of shot). This instrument is used on field for the identification of different materials, as well as for the definition of maps (e.g geological maps) if coupled with other hyperspectral instruments. 2) Hyperspectral sensor SIM-GA (Selex Galileo Multisensor Hyperspectral System), a system with spatial acquisition of data which may be used on an earth as well as on an airborne platform. SIM-GA consists of two electro-optical heads, which operate in the VNIR and SWIR regions, respectively, between 400-1000 nm and 1000-2500 nm (3). Although the spectral signature in the VNIR of many minerals is known, the co-presence of more minerals on a surface can affect the quantitative analysis of gypsum. Different minerals, such as gypsum, calcite, weddellite, whewellite, and other components (i.e. carbon particles in black crusts) are, in fact, commonly found on historical surfaces. In order to illustrate the complexity, but also the potentiality of hyperspectral sensors (portable or remote sensing) for the characterization of stone surfaces, a case study, the Facade of Santa Maria Novella in Florence - Italy, will be presented. References 1) R.N. Clark and G.A. Swayze, 1995, "Mapping minerals, amorphous materials, environmental materials, vegetation, water, ice, and snow, and other materials: The USGS Tricorder Algorithm", in "Summaries of the Fifth Annual JPL Airborne Earth Science Workshop", JPL Publication 95-1,1,39-40 2) E. Ben-Dor, K. Patin, A. Banin and A. Karnieli, 2002, "Mapping of several soil properties using DATS-7915 hyperspectral scanner data. A case study over clayely soils in Israel", International Journal of Remote Sensing, 23(6), 1043-1062 3) S. Vettori, M. Benvenuti, M. Camaiti, L. Chiarantini, P. Costagliola, S. Moretti, E. Pecchioni, 2008, "Assessment of the deterioration status of

  9. Railway infrastructure monitoring with COSMO/SkyMed imagery and multi-temporal SAR interferometry

    NASA Astrophysics Data System (ADS)

    Chiaradia, M.; Nutricato, R.; Nitti, D. O.; Bovenga, F.; Guerriero, L.

    2012-12-01

    stripmap images (pol.: HH; look side: right; pass direction: ascending; beam: H4-03; resolution: 3x3 m2) have been acquired from October 2009 to April 2012, covering the Calabria's Tyrrhenian coast, between the towns of Palmi and Reggio Calabria. The imaged area is of strategic importance since the two towns are connected by a stretch of the Tyrrhenian railway line, a fundamental line (as classified by RFI, the Italian Rail Network) belonging to the TEN-T network, i.e. the trans-european transport network defined since early '90 by the European Commission. Moreover, Calabria region is a challenging area where carrying on an analysis on weathering-related slope movements . In Calabria, on 2009the geo-hydrological crisis was so severe that the Italian Government had to declare the "state of emergency ". This paper concerns the processing of the CSK dataset performed through the SPINUA algorithm a Persistent Scatterers Interferometry technique originally developed with the aim of detection and monitoring of coherent targets in non- or scarcely urbanized areas. The displacement maps derived on the area of interest will be presented and commented with particular attention to the potential impact that such EO-based product can have on the railway networks monitoring. Acknowledgments CSK data provided by ASI in the framework of the project CAR-SLIDE, funded by MIUR (PON01_00536)

  10. What is the phylogenetic signal limit from mitogenomes? The reconciliation between mitochondrial and nuclear data in the Insecta class phylogeny

    PubMed Central

    2011-01-01

    Background Efforts to solve higher-level evolutionary relationships within the class Insecta by using mitochondrial genomic data are hindered due to fast sequence evolution of several groups, most notably Hymenoptera, Strepsiptera, Phthiraptera, Hemiptera and Thysanoptera. Accelerated rates of substitution on their sequences have been shown to have negative consequences in phylogenetic inference. In this study, we tested several methodological approaches to recover phylogenetic signal from whole mitochondrial genomes. As a model, we used two classical problems in insect phylogenetics: The relationships within Paraneoptera and within Holometabola. Moreover, we assessed the mitochondrial phylogenetic signal limits in the deeper Eumetabola dataset, and we studied the contribution of individual genes. Results Long-branch attraction (LBA) artefacts were detected in all the datasets. Methods using Bayesian inference outperformed maximum likelihood approaches, and LBA was avoided in Paraneoptera and Holometabola when using protein sequences and the site-heterogeneous mixture model CAT. The better performance of this method was evidenced by resulting topologies matching generally accepted hypotheses based on nuclear and/or morphological data, and was confirmed by cross-validation and simulation analyses. Using the CAT model, the order Strepsiptera was recovered as sister to Coleoptera for the first time using mitochondrial sequences, in agreement with recent results based on large nuclear and morphological datasets. Also the Hymenoptera-Mecopterida association was obtained, leaving Coleoptera and Strepsiptera as the basal groups of the holometabolan insects, which coincides with one of the two main competing hypotheses. For the Paraneroptera, the currently accepted non-monophyly of Homoptera was documented as a phylogenetic novelty for mitochondrial data. However, results were not satisfactory when exploring the entire Eumetabola, revealing the limits of the phylogenetic

  11. Study of microarthropod communities to assess soil quality in different managed vineyards

    NASA Astrophysics Data System (ADS)

    Gagnarli, Elena; Vignozzi, Nadia; Valboa, Giuseppe; Bouneb, Mabrouk; Corino, Lorenzo; Goggioli, Donatella; Guidi, Silvia; Lottero, Mariarosa; Tarchi, Franca; Simoni, Sauro

    2014-05-01

    conventional/IPM management). The mites represented about 50% of the arthropodofauna recorded, collembolans 30%, and 20% other microarthropods (Blattaria, Chilopoda, Coleoptera, Diplopoda, Diplura, Diptera, Hemiptera, Hymenoptera, Isopoda, Homoptera, Pauropoda, Protura, Pseudoscopionida, Psocoptera, Symphyla, Thysanoptera). The mesofauna abundance was affected by the type of management (P=0.015) and soil texture (P=0.029). At the identification level considered, the biological indices calculated showed no substantial differences between different crop managements (H'=1.26, D=0.97 in organic vineyard, H'=1.30, D=0.89 in IPM vineyard). The analysis of microarthropod communities by QBSar, however, showed higher values in organic compared to IPM managed vineyards (QBSar 199 vs 98 in 2011 and 205 vs 188 in 2012, respectively) which are close to figures characteristic of preserved soils.

  12. Artificial and factitious foods support the development and reproduction of the predatory mite Amblyseius swirskii.

    PubMed

    Nguyen, Duc Tung; Vangansbeke, Dominiek; De Clercq, Patrick

    2014-02-01

    The generalist predatory mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) was reared on Ephestia kuehniella Zeller eggs (Lepidoptera: Pyralidae), decapsulated dry cysts of the brine shrimp Artemia franciscana Kellogg (Anostraca: Artemiidae), and on meridic artificial diets (composed of honey, sucrose, tryptone, yeast extract, and egg yolk) supplemented with pupal hemolymph of the Chinese oak silkworm Antheraea pernyi (Guérin-Méneville) (Lepidoptera: Saturniidae) (AD1), with E. kuehniella eggs (AD2) or with A. franciscana cysts (AD3). Development, reproduction and predation capacity of the predatory mites were assessed in the first (G1) and sixth generation (G6) of rearing on the different diets. Immature survival rates in G1 were similar on all diets (96.8-100 %). After six generations, however, survival of A. swirskii was significantly reduced on all diets except on A. franciscana cysts. Oviposition rates did not differ between generations when females were fed on E. kuehniella, AD2 or AD3. The total number of deposited eggs was similar among diets except in G6 where the females fed on A. franciscana cysts produced more eggs than those maintained on E. kuehniella eggs. On most diets the intrinsic rates of increase in G1 were superior to those in G6, except for predators supplied with A. franciscana cysts where no differences were observed among generations. Female mites did not lose their capacity to kill first instar Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) after six generations on the different diets, but predation rates in G6 on E. kuehniella were lower than in G1. In conclusion, the different factitious and artificial diets tested in the present study supported the development and reproduction of A. swirskii for a single generation but fitness losses occurred to a varying degree after several generations on E. kuehniella eggs or the artificial diets. Artificial diet enriched with A. franciscana cysts yielded better results

  13. Developmental profile and hormonal regulation of the transcription factors broad and Krüppel homolog 1 in hemimetabolous thrips.

    PubMed

    Minakuchi, Chieka; Tanaka, Miho; Miura, Ken; Tanaka, Toshiharu

    2011-02-01

    In holometabolous insects, Krüppel homolog 1 (Kr-h1) and broad (br) are key players in the juvenile hormone (JH) regulation of metamorphosis: Kr-h1 is an early JH-response gene, while br is a transcription factor that directs pupal development. Thrips (Thysanoptera) are classified as hemimetabolous insects that develop directly from nymph to adult, but they have quiescent and non-feeding stages called propupa and pupa. We analyzed the developmental profiles of br and Kr-h1 in the western flower thrips Frankliniella occidentalis (Thripidae) that has one propupal instar and one pupal instar, and Haplothrips brevitubus (Phlaeothripidae) that has one propupal instar and two pupal instars, i.e. pupa I and pupa II. In F. occidentalis, the br mRNA levels were moderate in the embryonic stage, high at the larva-propupa transition, and low in the pre-final larval instar and the pupal stage, while Kr-h1 mRNA levels were high in the embryonic stage, remained at a moderate level in the larval and propupal stages, and low in the pupal stage. The expression profiles in H. brevitubus were very similar to those in F. occidentalis, except that the increase of br expression in the final larval stage occurs more slowly in H. brevitubus, and that the mRNA levels of br and Kr-h1 remained high in pupa I of H. brevitubus and then decreased. These profiles of br and Kr-h1 were comparable to those in holometabolous insects, although br expression found in thrips' embryogenesis is reminiscent of several hemimetabolous species. Treatment with an exogenous JH mimic (JHM) in distinct developmental stages consistently resulted in lethality as pupa of F. occidentalis or pupa II of H. brevitubus. Treatment with JHM to newly molted propupae caused prolonged expression of Kr-h1 and br in both species, suggesting that Kr-h1 and br could be involved in mediating anti-metamorphic signals of JHM.

  14. Fusarium semitectum, a potential mycopathogen against thrips and mites in chilli, Capsicum annuum.

    PubMed

    Mikunthan, G; Manjunatha, M

    2006-01-01

    In India, chilli (Capsicum annuum L.) suffers with a characteristic leaf curl symptoms due to the attack of mite, Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae) and thrips, Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) or both. Experiments were conducted in the fields of College of Agriculture, Shimoga, India during kharif (September 2003 to January 2004) and summer (March-June) 2004. After proving its pathogenicity, the potential of the mycopathogen, Fusarium semitectum was evaluated under field conditions using the popular chilli variety "Byadagi". Different combinations of Fusarium semitectum formulations with monocrotophos (0.025% and 0.05%) were tested. Oil-emulsion and dust-water formulations (DWF) at 1x 10(8) spore/ml, DWF with monocrotophos and 5% Neem Seed Kernal Extract (NSKE) were evaluated. Population of S. dorsalis, P. latus, predatory mite Amblyseius ovalis and damage index were estimated. Populations of thrips, mite and the predatory mite were estimated at 15 days interval after 30 days of transplanting. Damage index was assessed using a visual rating method. Plant height, fruit length and dry chilli yield of each treatment were also taken. Among the treatments, oil-emulsion formulation and dust water formulation of F. semitectum in combination with monocrotophos (0.05%) reduced the population of thrips significantly over other treatments. Dust water formulation was achieved a significant decline of thrips population in chilli plants after 60 days of transplanting. This reduction of thrips population could be achieved due to the effect of second spraying, which was given at 50 days after transplanting. Chilli plant height and fruit length did not vary significantly among the treatment in both seasons. The highest dry chilli yield of 512 and 1058 kg/ha was recorded in dust water formulation in combination with monocrotophos (0.05%) followed by oil formulation (432 kg/ha and 763 kg/ha) in Kharif and summer seasons, respectively

  15. Entomological fauna from Reserva Biológica do Atol das Rocas, RN, Brazil: I. Morphospecies composition.

    PubMed

    Almeida; Marchon-Silva; Ribeiro; Serpa-Filho; Almeida; Costa

    2000-05-01

    Atol das Rocas, the unique atoll in the South-western Atlantic, is located 144 nautical miles (266 Km) northeast from the city of Natal, NE Brazil and 80 nautical miles from Arquipélago de Fernando de Noronha, with geographic co-ordinates 3 masculine51'S and 33 masculine49"W. It's of volcanic origin and coralline formation. The reef is ellipsoid, its largest axis (E-W) is approximately 3.7 km long, and the shortest (N-S) is 2.5 km. Inside the lagoon, there are two islands: the Ilha do Farol and Ilha do Cemitério, which comprehend 7.2 Km2 of emerged area. The Atol das Rocas lodges 143,000 birds, mainly by Sula dactilatra, S. leucogaster, Anous stolidus, A. minuta and Sterna fuscata. Due to their remote location, the islands remain largely undisturbed by the human activities. Aiming to a first characterization of the entomological diversity and the general trophic niches of atoll's entomofauna, three collects were made (1994, 1995 and 1996) utilizing several methods for a wide sample. One thousand six hundred and six insect specimens were collected belonging to eight orders: 1. Coleoptera - 333 individuals of Dermestidae (Dermestes cadaverinus); Tenebrionidae (Phaleria testacea and morphospecies) and Curculionidae (one morphospecies); 2. Dermaptera - 50 individuals of Carcinophoridae (Anisolabis maritima); 3. Diptera - 281 individuals of Ephydridae (Scatella sp. and Hecamede sp.) and Hippoboscidae (one morphospecies); 4. Hymenoptera - 45 individuals of Formicidae (Brachymyrmex sp.); 5. Lepidoptera - 111 individuals of Microlepidoptera (one morphospecies); 6. Mallophaga - 18 individuals in birds (two morphospecies); 7. Orthoptera - 237 individuals of Acrididae (Schistocerca cancellata), Tridactylidae (one morphospecies) and Blattidae (three morphospecies); 8. Thysanoptera -531 individuals (one morphospecies). Also were collected 112 individuals of Arachnida. The taxa of the Order Araneae were represented by the families: 1. Miturgidae (Cheiracanthium inclusum); 2

  16. The Strepsiptera problem: phylogeny of the holometabolous insect orders inferred from 18S and 28S ribosomal DNA sequences and morphology.

    PubMed

    Whiting, M F; Carpenter, J C; Wheeler, Q D; Wheeler, W C

    1997-03-01

    Phylogenetic relationships among the holometabolous insect orders were inferred from cladistic analysis of nucleotide sequences of 18S ribosomal DNA (rDNA) (85 exemplars) and 28S rDNA (52 exemplars) and morphological characters. Exemplar outgroup taxa were Collembola (1 sequence), Archaeognatha (1), Ephemerida (1), Odonata (2), Plecoptera (2), Blattodea (1), Mantodea (1), Dermaptera (1), Orthoptera (1), Phasmatodea (1), Embioptera (1), Psocoptera (1), Phthiraptera (1), Hemiptera (4), and Thysanoptera (1). Exemplar ingroup taxa were Coleoptera: Archostemata (1), Adephaga (2), and Polyphaga (7); Megaloptera (1); Raphidioptera (1); Neuroptera (sensu stricto = Planipennia): Mantispoidea (2), Hemerobioidea (2), and Myrmeleontoidea (2); Hymenoptera: Symphyta (4) and Apocrita (19); Trichoptera: Hydropsychoidea (1) and Limnephiloidea (2); Lepidoptera: Ditrysia (3); Siphonaptera: Pulicoidea (1) and Ceratophylloidea (2); Mecoptera: Meropeidae (1), Boreidae (1), Panorpidae (1), and Bittacidae (2); Diptera: Nematocera (1), Brachycera (2), and Cyclorrhapha (1); and Strepsiptera: Corioxenidae (1), Myrmecolacidae (1), Elenchidae (1), and Stylopidae (3). We analyzed approximately 1 kilobase of 18S rDNA, starting 398 nucleotides downstream of the 5' end, and approximately 400 bp of 28S rDNA in expansion segment D3. Multiple alignment of the 18S and 28S sequences resulted in 1,116 nucleotide positions with 24 insert regions and 398 positions with 14 insert regions, respectively. All Strepsiptera and Neuroptera have large insert regions in 18S and 28S. The secondary structure of 18S insert 23 is composed of long stems that are GC rich in the basal Strepsiptera and AT rich in the more derived Strepsiptera. A matrix of 176 morphological characters was analyzed for holometabolous orders. Incongruence length difference tests indicate that the 28S + morphological data sets are incongruent but that 28S + 18S, 18S + morphology, and 28S + 18S + morphology fail to reject the hypothesis of

  17. Studies on Neotropical Phasmatodea XVI: Revision of Haplopodini Günther, 1953 (rev. stat.), with notes on the subfamily Cladomorphinae Bradley & Galil, 1977 and the descriptions of a new tribe, four new genera and nine new species (Phasmatodea: "Anareolatae": Phasmatidae: Cladomorphinae).

    PubMed

    Hennemann, Frank H; Conle, Oskar V; Perez-Gelabert, Daniel E

    2016-01-01

    The anareolate New World subfamily Cladomorphinae Bradley & Galil, 1977 is reviewed and keys to the six tribes currently included are presented; these are: Cladomorphini Bradley & Galil, 1977, Cladoxerini Karny, 1923, Cranidiini Günther, 1953, Pterinoxylini n. trib., Hesperophasmatini Bradley & Galil, 1977 and Haplopodini Günther, 1953 rev. stat.. New diagnoses are presented for all these tribes and possible relationships within Cladomorphinae are discusssed. Morphology of the genitalia and egg-structures indicate Cladomorphinae as presently treated to be polyphyletic. Two subordinate groups are recognized within present Cladomorphinae, which differ considerably in numerous morphological characters of the insects and eggs. The first group and here regarded as Cladomorphinae sensu stricto is formed by the mostly South American Cladomorphini + Cranidiini + Cladoxerini, while the second group is formed by the predominantly Caribbean Hesperophasmatini + Pterinoxylini n. trib. + Haplopodini.        Members of the first group (= Cladomorphini sensu stricto) share the dorsally carinate basitarsus in which the two dorsal carinae are melted with another, increasingly elongated gonapophyses VIII of females which are noticeably longer than gonapophyses IX and lamellate as well as strongly displaced medioventral carina of the profemora. Cranidiini + Cladomorphini share the strongly elongated and filiform gonapophyses VIII and presence of gonoplacs in the females, specialized poculum of males and presence of a median line in the eggs. Cranidiini differs from all other tribes of Cladomorphinae by the entirely unarmed legs of both sexes, distinctly broadened and leaf-like body and prominent longitudinal keel of the mesosternum of females, prominently enlarged poculum and spinulose phallus of males as well as the conspicuous narrowing of the posteromedian gap of the internal micropylar plate of the eggs and noticeably separated median line. Cladomorphini is characteristic