Cotesia vestalis parasitization suppresses expression of a Plutella xylostella thioredoxin.

Science.gov (United States)

Shi, M; Zhao, S; Wang, Z-H; Stanley, D; Chen, X-X

2016-12-01

Thioredoxins (Trxs) are a family of small, highly conserved and ubiquitous proteins involved in protecting organisms against toxic reactive oxygen species. In this study, a typical thioredoxin gene, PxTrx, was isolated from Plutella xylostella. The full-length cDNA sequence is composed of 959 bp containing a 321 bp open reading frame that encodes a predicted protein of 106 amino acids, a predicted molecular weight of 11.7 kDa and an isoelectric point of 5.03. PxTrx was mainly expressed in larval Malpighian tubules and the fat body. An enriched recombinant PxTrx had insulin disulphide reductase activity and stimulated Human Embryonic Kidney 293 (HEK293) cell proliferation. It also protected supercoiled DNA and living HEK293 cells from H 2 O 2 -induced damage. Parasitization by Cotesia vestalis and injections of 0.05 and 0.01 equivalents of C. vestalis Bracovirus (CvBv), the symbiotic virus carried by the parasitoid, led to down-regulation of PxTrx expression in host fat body. Taken together, our results indicate that PxTrx contributes to the maintenance of P. xylostella cellular haemostasis. Host fat body expression of PxTrx is strongly attenuated by parasitization and by injections of CvBv. © 2016 The Royal Entomological Society.

Systematics and biology of Cotesia typhae sp. n. (Hymenoptera, Braconidae, Microgastrinae, a potential biological control agent against the noctuid Mediterranean corn borer, Sesamia nonagrioides

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Laure Kaiser

2017-07-01

Full Text Available Many parasitoid species are subjected to strong selective pressures from their host, and their adaptive response may result in the formation of genetically differentiated populations, called host races. When environmental factors and reproduction traits prevent gene flow, host races become distinct species. Such a process has recently been documented within the Cotesia flavipes species complex, all of which are larval parasitoids of moth species whose larvae are stem borers of Poales. A previous study on the African species C. sesamiae, incorporating molecular, ecological and biological data on various samples, showed that a particular population could be considered as a distinct species, because it was specialized at both host (Sesamia nonagrioides and plant (Typha domingensis levels, and reproductively isolated from other C. sesamiae. Due to its potential for the biological control of S. nonagrioides, a serious corn pest in Mediterranean countries and even in Iran, we describe here Cotesia typhae Fernandez-Triana sp. n. The new species is characterized on the basis of morphological, molecular, ecological and geographical data, which proved to be useful for future collection and rapid identification of the species within the species complex. Fecundity traits and parasitism success on African and European S. nonagrioides populations, estimated by laboratory studies, are also included.

Impact of terbufos on Cotesia flavipes, a parasitoid of Diatraea saccharalis

International Nuclear Information System (INIS)

Vargas, E.; Valverde, B.; Carazo, E.

1999-01-01

The effect of terbufos on larvae of Diatraea saccharalis and its parasitoid, Cotesia flavipes was evaluated in the laboratory. Bioassays were conducted to determine the dose response of non-parasitized larvae of D. saccharalis feeding on artificial diet contaminated with terbufos. From the dose-response curve based on larval fresh weight, sublethal doses ranging from 1.32 ppm to 108 ppm of terbufos were selected for further studying the effect of the insecticide on both species. Both parasitized and non-parasitized larvae were exposed to the selected sublethal doses of terbufos in the diet. Consumption of the insecticide by the host resulted in mortality of the parasitoid, increased length of its larval and pupal periods, decreased adult fresh weight and changes in sex proportions. These negative effects were more severe as the dose of the insecticide increased. D. saccharalis was also affected by terbufos; larvae showed abnormalities, the length of the larval and pupal periods increased and the proportion of the females was reduced. In a preliminary greenhouse bioassay, only traces of terbufos or its metabolites were found in treated maize plants and in tissue of D. saccharalis larvae feeding on them. (author)

PARASITISASI DAN KAPASITAS REPRODUKSI COTESIA FLAVIPES CAMERON (HYMENOPTERA: BRACONIDAE PADA INANG DAN INSTAR YANG BERBEDA DI LABORATORIUM

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Purnomo .

2012-02-01

Full Text Available Parasitization and reproductive capacity of Cotesia flavipes Cameron (Hymenoptaera: Braconidae on different hosts and instar in laboratory. C. flavipes is an important parasitoid on sugar cane spotted borer, Chilo sacchariphagus Bojer.  The biology informations of C. flavipes is needed in order to make more effective as acontroling agent. The objectives of this research were to investigate the effect of host species (C. sacchariphagus, C. auricilius, Scirpophaga nivella and different instar on parasitization and reproductive capacity of C. flavipes. The results showed that the best host for                    C.  flavipes is  C. sacchariphagus and at fifth instar of  C. sacchariphagus.

A Horizontally Transferred Autonomous Helitron Became a Full Polydnavirus Segment in Cotesia vestalis

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Pedro Heringer

2017-12-01

Full Text Available Bracoviruses associate symbiotically with thousands of parasitoid wasp species in the family Braconidae, working as virulence gene vectors, and allowing the development of wasp larvae within hosts. These viruses are composed of multiple DNA circles that are packaged into infective particles, and injected together with wasp’s eggs during parasitization. One of the viral segments of Cotesia vestalis bracovirus contains a gene that has been previously described as a helicase of unknown origin. Here, we demonstrate that this gene is a Rep/Helicase from an intact Helitron transposable element that covers the viral segment almost entirely. We also provide evidence that this element underwent at least two horizontal transfers, which appear to have occurred consecutively: first from a Drosophila host ancestor to the genome of the parasitoid wasp C. vestalis and its bracovirus, and then from C. vestalis to a lepidopteran host (Bombyx mori. Our results reinforce the idea of parasitoid wasps as frequent agents of horizontal transfers in eukaryotes. Additionally, this Helitron-bracovirus segment is the first example of a transposable element that effectively became a whole viral circle.

Mensuração dos custos de laboratório para produção da vespa Cotesia flavipes - inimigo natural da broca da cana-de-açúcar na Usina Naviraí S.A.: uma análise comparativa = Laboratory costs for production of the wasp Cotesia flavipes - natural enemy of the sugar cane borer at the Navirai S.A. factory: A comparative analysis

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Adélia Megumi Suguiyama

2015-04-01

Full Text Available O controle biológico usando parasitoides larvais e parasitóides de ovos específicos ou entomopatógenos (fungos, bactérias ou vírus, manipulados em criatórios artificiais e liberados massivamente para o controle da broca é o mais difundido. Dentre estes, no entanto, o que tem sido comumente utilizado em escala comercial é o controle biológico com parasitóides larvais. Neste contexto, a espécie Cotesia flavipes, é uma vespa parasitóide que combate a broca da cana-de-açúcar Diatraea saccharalis (Lepidóptera, uma praga que causa grandes perdas na produção da cana-de-açúcar. Em função da importância desse tipo de controle biológico, este trabalho tem como objetivo mensurar os custos do sistema de produção de Cotesia flavipes na Usina Naviraí S.A. – Açúcar e Álcool (USINAVI, localizada em Naviraí, Mato Grosso do Sul. Ressalta-se que devido aos danos causados pela broca, os prejuízos no campo chegam a 25% de perda da produtividade da cultura Neste sentido, como principais resultados do presente estudo, sugere-se: 1. Investir em treinamento e qualificação de pessoal de laboratório e de campo; 2. Pesquisas no sentido de ajustar à técnica de controle biológico às condições ecofisiológicas da região de plantio; 3. Controle rigoroso do processo em termos de assepsia e higienização. = The biological control using parasitoids and larval parasitoid eggs or specific entomopathogens (fungi, bacteria or viruses, manipulated in artificial breeding sites and released massively to control drill, is the most widespread. Among these, however, has commonly been used on a commercial scale is biological control using larval parasitoids. In this context, the Cotesia flavipes species is a parasitoid wasp that fighting drill cane sugar Diatraea saccharalis (Lepidoptera, a pest that causes major losses in the production of cane sugar. Because of the importance of this kind of biological control, this paper aims to measure the

Dicty_cDB: Contig-U12435-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available hromosome 2 map 4915084... 40 0.24 7 ( AY934834 ) Cotesia plutellae clone 501-510 NADH dehydrogenas... 40 0....25 2 ( AY934846 ) Cotesia plutellae clone 641-646 NADH dehydrogenas... 40 0.25 2 ( AY934845 ) Cotesia plutella...e clone 631-636 NADH dehydrogenas... 40 0.25 2 ( AY934844 ) Cotesia plutellae c...lone 611-620 NADH dehydrogenas... 40 0.25 2 ( AY934842 ) Cotesia plutellae clone 581-583 NADH dehydrogenas...... 40 0.25 2 ( AY934840 ) Cotesia plutellae clone 561-570 NADH dehydrogenas... 40 0.25 2 ( AY934839 ) Cotesia plutella

Description of a new species of the Nitidulid genus Platynema, Rits. (Orthogramma, Murray nec Guenée)

NARCIS (Netherlands)

Ritsema Cz., C.

1885-01-01

Of this species I have seen three specimens, captured in the Andaman Islands, and of these Mr. A. Sidney Olliff has been good enough to let the Leyden Museum have two; I therefore propose to call the species Platynema Olliffi. Length 4,5 mm. — Elongate, subparallel, gradually widening a little

Host location behavior of Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) in ambient and moderately elevated ozone in field conditions

International Nuclear Information System (INIS)

Pinto, D.M.; Himanen, S.J.; Nissinen, A.; Nerg, A.-M.; Holopainen, J.K.

2008-01-01

In field O 3 -enrichment experiments increased herbivore densities have been reported, which could be due to negatively affected host location behavior of natural enemies. We addressed the impact of doubling background O 3 on the host location of the parasitoid Cotesia plutellae by conducting 24-h trials in an open-air O 3 -fumigation system during two consecutive years. Two circles (radii 1.40 and 4.00 m) of Plutella xylostella-infested potted cabbage plants were placed in the O 3 and ambient plots. Female wasps were released into each plot from the center, and observed 5 times over a 24-h period to assess their host location capability. Thereafter, plants were kept in laboratory conditions until larvae pupation to determine parasitism rates. No significant differences were detected between ambient and O 3 -enriched environments either in the number of wasps found in the field, or in the percentages of parasitized larvae. This suggests that moderately elevated O 3 will not affect the behavior of this parasitoid. - Atmospheric ozone increases do not directly affect the biological control of the cabbage pest, Plutella xylostella

Host location behavior of Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) in ambient and moderately elevated ozone in field conditions

Energy Technology Data Exchange (ETDEWEB)

Pinto, D.M. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland)], E-mail: delia.pinto@uku.fi; Himanen, S.J. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland); Nissinen, A. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland); Agrifood Research Finland, Plant Protection, FIN-31600 Jokioinen (Finland); Nerg, A.-M.; Holopainen, J.K. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland)

2008-11-15

In field O{sub 3}-enrichment experiments increased herbivore densities have been reported, which could be due to negatively affected host location behavior of natural enemies. We addressed the impact of doubling background O{sub 3} on the host location of the parasitoid Cotesia plutellae by conducting 24-h trials in an open-air O{sub 3}-fumigation system during two consecutive years. Two circles (radii 1.40 and 4.00 m) of Plutella xylostella-infested potted cabbage plants were placed in the O{sub 3} and ambient plots. Female wasps were released into each plot from the center, and observed 5 times over a 24-h period to assess their host location capability. Thereafter, plants were kept in laboratory conditions until larvae pupation to determine parasitism rates. No significant differences were detected between ambient and O{sub 3}-enriched environments either in the number of wasps found in the field, or in the percentages of parasitized larvae. This suggests that moderately elevated O{sub 3} will not affect the behavior of this parasitoid. - Atmospheric ozone increases do not directly affect the biological control of the cabbage pest, Plutella xylostella.

Transient expression of protein tyrosine phosphatases encoded in Cotesia plutellae bracovirus inhibits insect cellular immune responses

Science.gov (United States)

Ibrahim, Ahmed M. A.; Kim, Yonggyun

2008-01-01

Several immunosuppressive factors are associated with parasitism of an endoparasitoid wasp, Cotesia plutellae, on the diamondback moth, Plutella xylostella. C. plutellae bracovirus (CpBV) encodes a large number of putative protein tyrosine phosphatases (PTPs), which may play a role in inhibiting host cellular immunity. To address this inhibitory hypothesis of CpBV-PTPs, we performed transient expression of individual CpBV-PTPs in hemocytes of the beet armyworm, Spodoptera exigua, and analyzed their cellular immune responses. Two different forms of CpBV-PTPs were chosen and cloned into a eukaryotic expression vector under the control of the p10 promoter of baculovirus: one with the normal cysteine active site (CpBV-PTP1) and the other with a mutated active site (CpBV-PTP5). The hemocytes transfected with CpBV-PTP1 significantly increased in PTP activity compared to control hemocytes, but those with CpBV-PTP5 exhibited a significant decrease in the PTP activity. All transfected hemocytes exhibited a significant reduction in both cell spreading and encapsulation activities compared to control hemocytes. Co-transfection of CpBV-PTP1 together with its double-stranded RNA reduced the messenger RNA (mRNA) level of CpBV-PTP1 and resulted in recovery of both hemocyte behaviors. This is the first report demonstrating that the polydnaviral PTPs can manipulate PTP activity of the hemocytes to interrupt cellular immune responses.

Characterization of a novel gene encoding ankyrin repeat domain from Cotesia vestalis polydnavirus (CvBV)

International Nuclear Information System (INIS)

Shi Min; Chen Yafeng; Huang Fang; Liu Pengcheng; Zhou Xueping; Chen Xuexin

2008-01-01

Cotesia vestalis (Haliday) is an endoparasitoid of Plutella xylostella (L.) larvae and injects a polydnavirus (CvBV) into its host during oviposition. In this report we describe the characterization of a gene (CvBV805) and its products. CvBV805 is located on the segment S8 of CvBV genome; it has a size of 909 bp and encodes a predicted protein of 125 amino acids. This protein contains an ankyrin repeat domain with a high degree of similarity with IκB-like genes. Gene transcripts were detected in extracts of the host as early as 2 h post-parasitization (p.p.) and continued to be detected through 24 h. Tissue-specific expression patterns showed that CvBV805 might be involved in early host immunosuppression. CvBV805 was detected in parasitized hosts at 12 h p.p. and in rBac-eGFP-CvBV805-infected Tn-5B1-4 cells at 72 h.p.i. by using western blots analysis. The size of the protein expressed in the host hemocytes and infected Tn-5B1-4 cells was 17 kDa and 56 kDa (including eGFP), respectively, which nearly corresponded with the predicted molecular weight (14.31 kDa) of CvBV805, suggesting that the protein did not undergo extensive post-translational modification. The protein was confirmed to be present within the nuclear region in hemocytes of the parasitized P. xylostella larvae at 48 h p.p. using confocal laser scanning microscopy

Relationship between oviposition, virulence gene expression and parasitism success in Cotesia typhae nov. sp. parasitoid strains.

Science.gov (United States)

Benoist, R; Chantre, C; Capdevielle-Dulac, C; Bodet, M; Mougel, F; Calatayud, P A; Dupas, S; Huguet, E; Jeannette, R; Obonyo, J; Odorico, C; Silvain, J F; Le Ru, B; Kaiser, L

2017-12-01

Studying mechanisms that drive host adaptation in parasitoids is crucial for the efficient use of parasitoids in biocontrol programs. Cotesia typhae nov. sp. (Fernández-Triana) (Hymenoptera: Braconidae) is a newly described parasitoid of the Mediterranean corn borer Sesamia nonagrioides (Lefebvre) (Lepidoptera: Noctuidae). Braconidae are known for their domesticated bracovirus, which is injected with eggs in the host larva to overcome its resistance. In this context, we compared reproductive success traits of four Kenyan strains of C. typhae on a French and a Kenyan populations of its host. Differences were found between the four strains and the two most contrasted ones were studied more thoroughly on the French host population. Parasitoid offspring size was correlated with parasitism success and the expression of bracovirus virulence genes (CrV1 and Cystatin) in the host larva after parasitism. Hybrids between these two parasitoid strains showed phenotype and gene expression profiles similar to the most successful parental strain, suggesting the involvement of dominant alleles in the reproductive traits. Ovary dissections revealed that the most successful strain injected more eggs in a single host larva than the less successful one, despite an equal initial ovocyte number in ovaries. It can be expected that the amount of viral particles increase with the number of eggs injected. The ability to bypass the resistance of the allopatric host may in consequence be related to the oviposition behaviour (eggs allocation). The influence of the number of injected eggs on parasitism success and on virulence gene expression was evaluated by oviposition interruption experiments.

Dicty_cDB: Contig-U13401-1 [Dicty_cDB

Lifescience Database Archive (English)

Full Text Available musculus c... 139 2e-31 AY651828_5( AY651828 |pid:none) Cotesia plutellae polydnavirus seg... 139 2e-31 AK30... 1e-29 AY651829_10( AY651829 |pid:none) Cotesia plutellae polydnavirus se... 132 1e-29 Z36237_5( Z36237 |pid...K294673_1( AK294673 |pid:none) Homo sapiens cDNA FLJ59320 complet... 127 6e-28 EF067328_9( EF067328 |pid:none) Cotesia plutella..._1( U20807 |pid:none) Bos taurus protein tyrosine phosphatas... 127 8e-28 AY651829_1( AY651829 |pid:none) Cotesia plutella...sph... 126 1e-27 EF067324_5( EF067324 |pid:none) Cotesia plutellae polydnavirus seg... 126 1e-27 AK064263_1(

Toxicity of Lavandula angustifolia oil constituents and spray formulations to insecticide-susceptible and pyrethroid-resistant Plutella xylostella and its endoparasitoid Cotesia glomerata.

Science.gov (United States)

Yi, Chang Geun; Hieu, Tran Trung; Lee, Si Hyeock; Choi, Byeoung-Ryeol; Kwon, Min; Ahn, Young-Joon

2016-06-01

Plutella xylostella is one of the most serious insect pests of cruciferous crops. This study was conducted to determine the toxicity of 21 constituents from Lavandula angustifolia essential oil (LA-EO) and another 16 previously known LA-EO constituents and the toxicity of six experimental spray formulations containing the oil (1-6 g L(-1) sprays) to susceptible KS-PX and pyrethroid-resistant JJ-PX P. xylostella larvae, as well as to its endoparasitoid Cotesia glomerata adults. Linalool and linalool oxide (LC50 = 0.016 mg cm(-3) ) were the most toxic fumigant compounds and were 10.7-fold less toxic than dichlorvos to KS-PX larvae. Either residual or fumigant toxicity of these compounds was almost identical against larvae from either of the two strains. Against C. glomerata, dichlorvos (LC50 = 7 × 10(-6)  mg cm(-3) ) was the most toxic insecticide. LA-EO was ∼1430 times less toxic than dichlorvos. The oil applied as 6 g L(-1) spray and emamectin benzoate 21.5 g L(-1) emulsifiable concentrate provided 100% mortality against larvae from either of the two strains. Reasonable P. xylostella control in greenhouses can be achieved by a spray formulation containing the 6 g L(-1) oil as potential contact-action fumigant. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Parasitism performance and fitness of Cotesia vestalis (Hymenoptera: Braconidae infected with Nosema sp. (Microsporidia: Nosematidae: implications in integrated pest management strategy.

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Nadia Kermani

Full Text Available The diamondback moth (DBM Plutella xylostella (L. has traditionally been managed using synthetic insecticides. However, the increasing resistance of DBM to insecticides offers an impetus to practice integrated pest management (IPM strategies by exploiting its natural enemies such as pathogens, parasitoids, and predators. Nevertheless, the interactions between pathogens and parasitoids and/or predators might affect the effectiveness of the parasitoids in regulating the host population. Thus, the parasitism rate of Nosema-infected DBM by Cotesia vestalis (Haliday (Hym., Braconidae can be negatively influenced by such interactions. In this study, we investigated the effects of Nosema infection in DBM on the parasitism performance of C. vestalis. The results of no-choice test showed that C. vestalis had a higher parasitism rate on non-infected host larvae than on Nosema-treated host larvae. The C. vestalis individuals that emerged from Nosema-infected DBM (F1 and their progeny (F2 had smaller pupae, a decreased rate of emergence, lowered fecundity, and a prolonged development period compared to those of the control group. DBM infection by Nosema sp. also negatively affected the morphometrics of C. vestalis. The eggs of female C. vestalis that developed in Nosema-infected DBM were larger than those of females that developed in non-infected DBM. These detrimental effects on the F1 and F2 generations of C. vestalis might severely impact the effectiveness of combining pathogens and parasitoids as parts of an IPM strategy for DBM control.

Protein tyrosine phosphatase encoded in Cotesia plutellae bracovirus suppresses a larva-to-pupa metamorphosis of the diamondback moth, Plutella xylostella.

Science.gov (United States)

Kim, Jiwan; Hepat, Rahul; Lee, Daeweon; Kim, Yonggyun

2013-09-01

Parasitization by an endoparasitoid wasp, Cotesia plutellae, inhibits a larva-to-pupa metamorphosis of the diamondback moth, Plutella xylostella. This study tested an inhibitory effect of C. plutellae bracovirus (CpBV) on the metamorphosis of P. xylostella. Parasitized P. xylostella exhibited significantly reduced prothoracic gland (PTG) development at the last instar compared to nonparasitized larvae. Expression of the ecdysone receptor (EcR) was markedly suppressed during the last instar larvae parasitized by C. plutellae. By contrast, expression of the insulin receptor (InR) significantly increased in the parasitized larvae. Microinjection of CpBV significantly inhibited the larva-to-pupa metamorphosis of nonparasitized larvae in a dose-dependent manner. Injection of CpBV also inhibited the expression of the EcR and increased the expression of the InR. Individual CpBV segments were transiently expressed in its encoded genes in nonparasitized larvae and screened to determine antimetamorphic viral gene(s). Out of 21 CpBV segments, two viral segments (CpBV-S22 and CpBV-S27) were proved to inhibit larva-to-pupa metamorphosis by transient expression assay. RNA interference of each gene encoded in the viral segments was applied to determine antimetamorphic gene(s). Protein tyrosine phosphatase, early expressed gene, and four hypothetical genes were selected to be associated with the antimetamorphic activity of CpBV. These results suggest that antimetamorphosis of P. xylostella parasitized by C. plutellae is induced by inhibiting PTG development and subsequent ecdysteroid signaling with viral factors of CpBV. Copyright © 2013 Elsevier Inc. All rights reserved.

Intrinsic competition among solitary and gregarious endoparasitoid wasps and phenomenon of resource sharing

NARCIS (Netherlands)

Magdaraog, P.M.; Harvey, J.A.; Tanaka, T.; Gols, R.

2012-01-01

1. Intrinsic competition was compared in three species of braconid wasps, the solitary Meteorus pulchricornis Wesmael, and the gregarious Cotesia kariyai (Watanabe) and Cotesia ruficrus Haliday in caterpillars of their common host, the armyworm Mythimna separata Walker. Competition was determined in

Intrinsic competition among solitary and gregarious endoparasitoid wasps and the phenomenon of ‘resource sharing’

NARCIS (Netherlands)

Magdaraog, P.M.; Harvey, J.A.; Tanaka, T.; Gols, R.

2012-01-01

1. Intrinsic competition was compared in three species of braconid wasps, the solitary Meteorus pulchricornis Wesmael, and the gregarious Cotesia kariyai (Watanabe) and Cotesia ruficrus Haliday in caterpillars of their common host, the armyworm Mythimna separata Walker. Competition was determined in

CREB expression in the brains of two closely related parasitic wasp species that differ in long-term memory formation

NARCIS (Netherlands)

Van den Berg, M.; Verbaarschot, P.; Hontelez, S.; Vet, L.E.M.; Dicke, M.; Smid, H.M.

2010-01-01

The cAMP/PKA signalling pathway and transcription factor cAMP response element-binding protein (CREB) play key roles in long-term memory (LTM) formation. We used two closely related parasitic wasp species, Cotesia glomerata and Cotesia rubecula, which were previously shown to be different in LTM

Efeito de Extratos Aquosos de Azadirachta indica na Sobrevivência de Diatraea saccharalis e do Parasitóide Cotesia flavipes

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Fábio Mazzonetto

2013-09-01

Full Text Available O objetivo do presente trabalho foi avaliar o efeito de extratos aquosos de Azadirachta indica na sobrevivência de Diatraea saccharalis e do parasitóide Cotesia flavipes. Para a obtenção do extrato vegetal de A. indica, as folhas secas em estufa de circulação forçada de ar (40oC durante 48h, posteriormente trituradas em moinho de facas até obtenção do pó. Os extratos foram obtidos a partir da adição de 0,5; 1,0; 2,0; 3,0 e 5,0g do pó vegetal em 100ml de água destilada formando respectivamente as concentrações. O delineamento experimental foi inteiramente casualizado, com seis tratamentos (testemunha, 0,5%, 1%, 2%, 3% e 5% de extrato aquoso de A. indica e 40 repetições. Para a análise estatística utilizou-se o método de Kaplan-Meier e o teste de Log-Rank na obtenção e comparação das curvas de sobrevivência. Já para a análise dos dados de emergência de adultos do parasitóide C. flavipes foi utilizado o teste de Scott-Knott ao nível de 5% de probabilidade.  As lagartas D. saccharalis apresentaram um menor tempo de sobrevivência quando expostas as dietas artificiais contendo as diferentes concentrações do extrato aquoso de A. indica.  A utilização de extrato aquoso de A. indica afetou negativamente a emergência de adultos de C. flavipes, importante parasitóide de D. saccharalis, quando submetidos ao parasitismo de lagartas tratadas com extrato aquoso de folhas deste vegetal.

Duration of plant damage by host larvae affects attraction of two parasitoid species (Microplitis croceipes and Cotesia marginiventris) to cotton: implications for interspecific competition.

Science.gov (United States)

Morawo, Tolulope; Fadamiro, Henry

2014-12-01

Volatile organic compounds (VOCs) released by herbivore-damaged plants can guide parasitoids to their hosts. The quantity and quality of VOC blends emitted by plants may be affected by the duration of plant damage by herbivores, which could have potential ramifications on the recruitment of competing parasitoids. We used two parasitoid species, Microplitis croceipes and Cotesia marginiventris (Hymenoptera: Braconidae), to address the question of whether duration of plant damage affects parasitoid use of plant VOCs for host location. Both wasp species are larval endoparasitoids of Heliothis virescens (Lepidoptera: Noctuidae), an important pest of cotton. Attraction of the two parasitoid species to odors emitted by undamaged (UD), fresh (6 h infestation) damage (FD), and old (24 h infestation) damage (OD) cotton plants infested by H. virescens larvae was investigated using a headspace volatile collection system coupled with four-choice olfactometer bioassay. Both sexes of M. croceipes showed a preference for FD- and OD-plant odors over UD-plants. On the other hand, more C. marginiventris females were attracted to UD- and FD-plants than to OD-plants. GC/MS analyses showed qualitative and quantitative differences in the VOC profiles of UD, FD, and OD-plants, which may explain the observed preferences of the parasitoids. These results suggest a temporal partitioning in the recruitment of M. croceipes and C. marginiventris to H. virescens-damaged cotton, and may have potential implications for interspecific competition between the two parasitoid species.

Eco Control of Agro Pests using Imaging, Modelling & Natural Predators

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Fina Faithpraise

2014-10-01

Full Text Available Caterpillars in their various forms: size, shape, and colour cause significant harm to crops and humans. This paper offers a solution for the detection and control of caterpillars through the use of a sustainable pest control system that does not require the application of chemical pesticides, which damage human health and destroy the naturally beneficial insects within the environment. The proposed system is capable of controlling 80% of the population of caterpillars in less than 65 days by deploying a controlled number of larval parasitoid wasps (Cotesia Flavipes, Cameron into the crop environment. This is made possible by using a continuous time model of the interaction between the caterpillar and the Cotesia Flavipes (Cameron wasps using a set of simultaneous, non-linear, ordinary differential equations incorporating natural death rates based on the Weibull probability distribution function. A negative binomial distribution is used to model the efficiency and the probability that the wasp will find and parasitize a host larva. The caterpillar is presented in all its life-cycle stages of: egg, larva, pupa and adult and the Cotesia Flavipes (Cameron wasp is present as an adult larval parasitoid. Biological control modelling is used to estimate the quantity of the Cotesia Flavipes (Cameron wasps that should be introduced into the caterpillar infested environment to suppress its population density to an economically acceptable level within a prescribed number of days.

Permanent Genetic Resources added to Molecular Ecology Resources database 1 January 2009-30 April 2009.

Science.gov (United States)

Abercrombie, L G; Anderson, C M; Baldwin, B G; Bang, I C; Beldade, R; Bernardi, G; Boubou, A; Branca, A; Bretagnolle, F; Bruford, M W; Buonamici, A; Burnett, R K; Canal, D; Cárdenas, H; Caullet, C; Chen, S Y; Chun, Y J; Cossu, C; Crane, C F; Cros-Arteil, S; Cudney-Bueno, R; Danti, R; Dávila, J A; Della Rocca, G; Dobata, S; Dunkle, L D; Dupas, S; Faure, N; Ferrero, M E; Fumanal, B; Gigot, G; González, I; Goodwin, S B; Groth, D; Hardesty, B D; Hasegawa, E; Hoffman, E A; Hou, M L; Jamsari, A F J; Ji, H J; Johnson, D H; Joseph, L; Justy, F; Kang, E J; Kaufmann, B; Kim, K S; Kim, W J; Koehler, A V; Laitung, B; Latch, P; Liu, Y D; Manjerovic, M B; Martel, E; Metcalfe, S S; Miller, J N; Midgley, J J; Migeon, A; Moore, A J; Moore, W L; Morris, V R F; Navajas, M; Navia, D; Neel, M C; De Nova, P J G; Olivieri, I; Omura, T; Othman, A S; Oudot-Canaff, J; Panthee, D R; Parkinson, C L; Patimah, I; Pérez-Galindo, C A; Pettengill, J B; Pfautsch, S; Piola, F; Potti, J; Poulin, R; Raimondi, P T; Rinehart, T A; Ruzainah, A; Sarver, S K; Scheffler, B E; Schneider, A R R; Silvain, J F; Siti Azizah, M N; Springer, Y P; Stewart, C N; Sun, W; Tiedemann, R; Tsuji, K; Trigiano, R N; Vendramin, G G; Wadl, P A; Wang, L; Wang, X; Watanabe, K; Waterman, J M; Weisser, W W; Westcott, D A; Wiesner, K R; Xu, X F; Yaegashi, S; Yuan, J S

2009-09-01

This article documents the addition of 283 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Agalinis acuta; Ambrosia artemisiifolia; Berula erecta; Casuarius casuarius; Cercospora zeae-maydis; Chorthippus parallelus; Conyza canadensis; Cotesia sesamiae; Epinephelus acanthistius; Ficedula hypoleuca; Grindelia hirsutula; Guadua angustifolia; Leucadendron rubrum; Maritrema novaezealandensis; Meretrix meretrix; Nilaparvata lugens; Oxyeleotris marmoratus; Phoxinus neogaeus; Pristomyrmex punctatus; Pseudobagrus brevicorpus; Seiridium cardinale; Stenopsyche marmorata; Tetranychus evansi and Xerus inauris. These loci were cross-tested on the following species: Agalinis decemloba; Agalinis tenella; Agalinis obtusifolia; Agalinis setacea; Agalinis skinneriana; Cercospora zeina; Cercospora kikuchii; Cercospora sorghi; Mycosphaerella graminicola; Setosphaeria turcica; Magnaporthe oryzae; Cotesia flavipes; Cotesia marginiventris; Grindelia Xpaludosa; Grindelia chiloensis; Grindelia fastigiata; Grindelia lanceolata; Grindelia squarrosa; Leucadendron coniferum; Leucadendron salicifolium; Leucadendron tinctum; Leucadendron meridianum; Laodelphax striatellus; Sogatella furcifera; Phoxinus eos; Phoxinus rigidus; Phoxinus brevispinosus; Phoxinus bicolor; Tetranychus urticae; Tetranychus turkestani; Tetranychus ludeni; Tetranychus neocaledonicus; Tetranychus amicus; Amphitetranychus viennensis; Eotetranychus rubiphilus; Eotetranychus tiliarium; Oligonychus perseae; Panonychus citri; Bryobia rubrioculus; Schizonobia bundi; Petrobia harti; Xerus princeps; Spermophilus tridecemlineatus and Sciurus carolinensis. © 2009 Blackwell Publishing Ltd.

The Cotesia sesamiae story: insight into host-range evolution in a Hymenoptera parasitoid and implication for its use in biological control programs.

Science.gov (United States)

Kaiser, L; Dupas, S; Branca, A; Herniou, E A; Clarke, C W; Capdevielle Dulac, C; Obonyo, J; Benoist, R; Gauthier, J; Calatayud, P A; Silvain, J F; Le Ru, B P

2017-12-01

This review covers nearly 20 years of studies on the ecology, physiology and genetics of the Hymenoptera Cotesia sesamiae, an African parasitoid of Lepidoptera that reduces populations of common maize borers in East and South Africa. The first part of the review presents studies based on sampling of C. sesamiae from maize crops in Kenya. From this agrosystem including one host plant and three main host borer species, studies revealed two genetically differentiated populations of C. sesamiae species adapted to their local host community, and showed that their differentiation involved the joint evolution of virulence genes and sensory mechanisms of host acceptance, reinforced by reproductive incompatibility due to Wolbachia infection status and natural inbreeding. In the second part, we consider the larger ecosystem of wild Poales plant species hosting many Lepidoptera stem borer species that are potential hosts for C. sesamiae. The hypothesis of other host-adapted C. sesamiae populations was investigated based on a large sampling of stem borer larvae on various Poales across sub-Saharan Africa. The sampling provided information on the respective contribution of local hosts, biogeography and Wolbachia in the genetic structure of C. sesamiae populations. Molecular evolution analyses highlighted that several bracovirus genes were under positive selection, some of them being under different selection pressure in C. sesamiae populations adapted to different hosts. This suggests that C. sesamiae host races result from co-evolution acting at the local scale on different bracovirus genes. The third part considers the mechanisms driving specialization. C. sesamiae host races are more or less host-specialized. This character is crucial for efficient and environmentally-safe use of natural enemies for biological control of pests. One method to get an insight in the evolutionary stability of host-parasite associations is to characterize the phylogenetic relationships between

Author Details

African Journals Online (AJOL)

Lepidoptera: Plutellidae) Populations on Cabbage Brassica oleracea var. capitata (L.) by Cotesia plutellae (Kurdjumov) (Hymenoptera: Braconidae) in Ghana Abstract PDF. ISSN: 0855-4307. AJOL African Journals Online. HOW TO USE AJOL.

Assessing the suitability of flowering herbs as parasitoid food sources: flower attractiveness and nectar accessibility

NARCIS (Netherlands)

Wäckers, F.L.

2004-01-01

Eleven insect-pollinated plant species were investigated with respect to their olfactory attractiveness and nectar accessibility for the parasitoid species Cotesia glomerata (Hymenoptera: Braconidae), Heterospilus prosopidis (Hymenoptera: Braconidae), and Pimpla turionellae (Hymenoptera:

Development of two related endoparasitoids in larvae of the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae)

NARCIS (Netherlands)

Malčická, Mima; Harvey, Jeffrey A.

2015-01-01

We compare the growth and development of two related solitary endoparasitoids (Braconidae, Microgastinae) in different instars (second and third) of the diamondback moth Plutella xylostella. Cotesia vestalis is a well-studied parasitoid whose larvae feed primarily on host hemolymph and fat body

Differences in memory dynamics between two closely related parasitoid wasp species

NARCIS (Netherlands)

Bleeker, M.A.K.; Smid, H.M.; Steidle, J.L.M.; Kruidhof, H.M.; van Loon, J.J.A.; Vet, L.E.M.

2006-01-01

The two closely related parasitoids Cotesia glomerata and C. rubecula (Hymenoptera: Braconidae) coexist in The Netherlands where they occupy slightly different niches. When searching for their caterpillar hosts, they use host plant odours that are released upon feeding by the caterpillars. The

Interactions between microbial agents and gypsy moth parasites

Science.gov (United States)

Ronald M. Weseloh

1985-01-01

The parasite Cotesia melanoscelus attacks small gypsy moth larvae more successfully than large ones, and Bacillus thuringiensis retards the growth of caterpillars it does not kill. Together, both factors lead to higher parasitism by C. melanoscelus in areas sprayed with B. thuringiensis than...

ß-Glucosidase: an elicitor of herbivore-induced plant odor that attracts host-searching parasitic wasps.

NARCIS (Netherlands)

Mattiacci, L.; Dicke, M.; Posthumus, M.A.

1995-01-01

Cabbage plants respond to caterpillar (Pieris brassicae) herbivory by releasing a mixture of volatiles that makes them highly attractive to parasitic wasps (Cotesia glomerata) that attack the herbivores. Cabbage leaves that are artificially damaged and subsequently treated with gut regurgitant of P.

Impact of botanical pesticides derived from Melia azedarach and Azadirachta indica on the biology of two parasitoid species of the diamondback moth

NARCIS (Netherlands)

Charleston, D.S.; Kfir, R.; Dicke, M.; Vet, L.E.M.

2005-01-01

The effect of two botanical pesticides was tested on two species of parasitoids, Cotesia plutellae and Diadromus collaris. Aqueous leaf extracts from the syringa tree, Melia azedarach and commercial formulations from the neem tree, Azadirachta indica, Neemix 4.5 were investigated in the laboratory

Ambient ultraviolet radiation induces protective responses in soybean but does not attenuate indirect defense

International Nuclear Information System (INIS)

Winter, Thorsten R.; Rostas, Michael

2008-01-01

We investigated the effects of ambient ultraviolet (UV) radiation on (i) the performance and chemistry of soybean plants, (ii) the performance of Spodoptera frugiperda and (iii) the foraging behavior of the herbivore's natural enemy Cotesia marginiventris which exploits herbivore-induced plant volatiles (VOC) for host location. The accumulation of protective phenolics was faster in plants receiving ambient UV than in controls exposed to sun light lacking UV. Accordingly, isorhamnetin- and quercetin-based flavonoids were increased in UV exposed plants. No UV effects were found on the performance and feeding behavior of S. frugiperda. Herbivore-damaged plants emitted the same VOC when grown under ambient or attenuated UV for 5, 10 or 30 days. Consequently, C. marginiventris was attracted but did not discriminate between exposed and unexposed soybeans. In summary, ambient UV radiation affected soybean morphology and physiology but did not destabilize interactions between trophic levels. - Ambient ultraviolet radiation does not alter induced VOC emission in soybean and thus host location of the parasitoid Cotesia marginiventris remains effective

Ambient ultraviolet radiation induces protective responses in soybean but does not attenuate indirect defense

Energy Technology Data Exchange (ETDEWEB)

Winter, Thorsten R. [Department of Botany II, Julius-von-Sachs Institute for Biosciences, University of Wuerzburg, Julius-von-Sachs-Platz 3, 97082 Wuerzburg (Germany); Rostas, Michael [Department of Botany II, Julius-von-Sachs Institute for Biosciences, University of Wuerzburg, Julius-von-Sachs-Platz 3, 97082 Wuerzburg (Germany)], E-mail: rostas@botanik.uni-wuerzburg.de

2008-09-15

We investigated the effects of ambient ultraviolet (UV) radiation on (i) the performance and chemistry of soybean plants, (ii) the performance of Spodoptera frugiperda and (iii) the foraging behavior of the herbivore's natural enemy Cotesia marginiventris which exploits herbivore-induced plant volatiles (VOC) for host location. The accumulation of protective phenolics was faster in plants receiving ambient UV than in controls exposed to sun light lacking UV. Accordingly, isorhamnetin- and quercetin-based flavonoids were increased in UV exposed plants. No UV effects were found on the performance and feeding behavior of S. frugiperda. Herbivore-damaged plants emitted the same VOC when grown under ambient or attenuated UV for 5, 10 or 30 days. Consequently, C. marginiventris was attracted but did not discriminate between exposed and unexposed soybeans. In summary, ambient UV radiation affected soybean morphology and physiology but did not destabilize interactions between trophic levels. - Ambient ultraviolet radiation does not alter induced VOC emission in soybean and thus host location of the parasitoid Cotesia marginiventris remains effective.

¿Multiplicar Tetrastichus howardi (Hymenoptera: Eulophidae en la oruga de la seda afecta su biología?

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Nahara Gabriela Piñeyro

2016-01-01

Full Text Available La multiplicación sucesiva de parasitoides en hospederos alternativos, puede afectar las características biológicas y comprometer los sistemas de cría masiva de estos. El objetivo de este trabajo fue evaluar la multiplicación de Tetrastichus howardi (Olliff, 1893 (Hymenoptera: Eulophidae en pupas del hospedero alternativo Bombyx mori (Linnaeus, 1758 (Lepidoptera: Bombycidae, durante tres generaciones. Y si eso afecta su desempeño reproductivo, cuando se cría, posteriormente, en pupas del hospedero natural Diatraea saccharalis (Fabricius, 1794 (Lepidoptera: Crambidae. Las informaciones obtenidas en este estudio pueden mejorar y facilitar el control biológico de plagas, principalmente, con la utilización de parasitoides, debido a que T. howardi parasita y se desarrolla en pupas de B. mori. De forma general, la multiplicación de T. howardi durante tres generaciones en pupas del hospedero alternativo B. mori no compromete las características biológicas de este parasitoide cuando se multiplica en su hospedero natural D. saccharalis a los efectos de su utilización en programas de control biológico.

Reward value determines memory consolidation in parasitic wasps.

Science.gov (United States)

Kruidhof, H Marjolein; Pashalidou, Foteini G; Fatouros, Nina E; Figueroa, Ilich A; Vet, Louise E M; Smid, Hans M; Huigens, Martinus E

2012-01-01

Animals can store learned information in their brains through a series of distinct memory forms. Short-lasting memory forms can be followed by longer-lasting, consolidated memory forms. However, the factors determining variation in memory consolidation encountered in nature have thus far not been fully elucidated. Here, we show that two parasitic wasp species belonging to different families, Cotesia glomerata (Hymenoptera: Braconidae) and Trichogramma evanescens (Hymenoptera; Trichogrammatidae), similarly adjust the memory form they consolidate to a fitness-determining reward: egg-laying into a host-insect that serves as food for their offspring. Protein synthesis-dependent long-term memory (LTM) was consolidated after single-trial conditioning with a high-value host. However, single-trial conditioning with a low-value host induced consolidation of a shorter-lasting memory form. For Cotesia glomerata, we subsequently identified this shorter-lasting memory form as anesthesia-resistant memory (ARM) because it was not sensitive to protein synthesis inhibitors or anesthesia. Associative conditioning using a single reward of different value thus induced a physiologically different mechanism of memory formation in this species. We conclude that the memory form that is consolidated does not only change in response to relatively large differences in conditioning, such as the number and type of conditioning trials, but is also sensitive to more subtle differences, such as reward value. Reward-dependent consolidation of exclusive ARM or LTM provides excellent opportunities for within-species comparison of mechanisms underlying memory consolidation.

Differential performance and parasitism of caterpillars on maize inbred lines with distinctly different herbivore-induced volatile emissions.

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Thomas Degen

Full Text Available Plant volatiles induced by insect feeding are known to attract natural enemies of the herbivores. Six maize inbred lines that showed distinctly different patterns of volatile emission in laboratory assays were planted in randomized plots in the Central Mexican Highlands to test their ability to recruit parasitic wasps under field conditions. The plants were artificially infested with neonate larvae of the fall armyworm Spodoptera frugiperda, and two of its main endoparasitoids, Campoletis sonorensis and Cotesia marginiventris, were released in the plots. Volatiles were collected from equally treated reference plants in the neighbourhood of the experimental field. The cumulative amount of 36 quantified volatile compounds determined for each line was in good accordance with findings from the laboratory; there was an almost 15-fold difference in total emission between the two extreme lines. We found significant differences among the lines with respect to the numbers of armyworms recovered from the plants, their average weight gain and parasitism rates. Average weight of the caterpillars was negatively correlated with the average total amount of volatiles released by the six inbred lines. However, neither total volatile emission nor any specific single compound within the blend could explain the differential parasitism rates among the lines, with the possible exception of (E-2-hexenal for Campoletis sonorensis and methyl salicylate for Cotesia marginiventris. Herbivore-induced plant volatiles and/or correlates thereof contribute to reducing insect damage of maize plants through direct plant defence and enhanced attraction of parasitoids, alleged indirect defence. The potential to exploit these volatiles for pest control deserves to be further evaluated.

WASP-ASSOCIATED FACTORS ACT IN INTERSPECIES COMPETITION DURING MULTIPARASITISM.

Science.gov (United States)

Magdaraog, Peter M; Tanaka, Toshiharu; Harvey, Jeffrey A

2016-06-01

Coexistence or displacement of parasitoids in hosts during intrinsic competitive interactions between different parasitoid species (multiparasitism) may depend on their life history traits and behavior. Intense competition for possession of hosts may lead to the elimination of the inferior competitor through physical attack and/or physiological suppression. However, the mechanisms of physiological suppression during multiparasitism remain unclear. Previous work has shown that first instar larvae of the solitary endoparasitoid Meteorus pulchricornis possess well-developed mandibles that are used to kill competitors. Two gregarious endoparasitoids, Cotesia kariyai and C. rufricus, share host resources especially when the time gap of oviposition is short. Here, we investigated the physiological influence of wasp-regulatory factors of the three endoparasitoids, M. pulchricornis, C. kariyai, and C. ruficrus, in their common host Mythimna separata. We found that MpVLP alone (or with venom) deleteriously affected the development of the two gregarious species. Similarly, CkPDV plus venom had toxic effect on M. pulchricornis eggs and immature larvae, although they were not harmful to immature stages of C. ruficrus. Cotesia kariyai and C. ruficrus were able to coexist mainly through the expression of regulatory factors and both could successfully emerge from a multiparasitized host. The injection of CkPDV plus venom after oviposition in L5 host larvae facilitated C. ruficrus development and increased the rate of successful parasitism from 9% to 62%. This suggests that the two gregarious parasitoid wasps exhibit strong phylogenetic affinity, favoring their coexistence and success in multiparasitized hosts. © 2016 Wiley Periodicals, Inc.

Aspectos bionômicos de Eois tegularia (Guenée e Eois glauculata (Walker (Lepidoptera, Geometridae, Larentiinae e seus parasitóides Bionomic aspects of Eois tegularia (Guenée and Eois glauculata (Walker (Lepidoptera, Geometridae, Larentiinae and their parasitoids

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Sandra Maria Pasenow Braga

2001-09-01

Full Text Available Eois tegularia (Guenée, [1858] and Eois glauculata (Walker, [1863] larvae were studied by one year in semidec iduous forest at Canchim Farm (EMBRAPA, São Carlos, São Paulo, Brazil. Specimens were hosted by species of Piper Linnaeus (Piperaceae: P. mollicomum Kunth, P. amalogo Linnaeus, P. glabratum Kunth and P. gaudichaudianum Kunth. Some parasitoids were reared from the larvae of Eois Hübner, 1818 species, as follow. Hymenoptera: Cotesia Cameron, 1891, Apanteles Foerster, 1862, Glyptapanteles Ashmead, 1904, Dolichogenidea Viereck, 1911, Meteorus Haliday, 1835 (Braconidae; Mesochorus Gravenhorst, 1829, Venturia Schrottky, 1902 (Ichneumonidae; Elachertus Spinola, 1811 (Eulophidae; Perilampus Latreille, 1809 (Perilampidae, Diptera: Myiopharus Brauer & Bergenstamm, 1889 (Tachinidae.

Herbivore-specific, density-dependent induction of plant volatiles: honest or "cry wolf" signals?

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Kaori Shiojiri

Full Text Available Plants release volatile chemicals upon attack by herbivorous arthropods. They do so commonly in a dose-dependent manner: the more herbivores, the more volatiles released. The volatiles attract predatory arthropods and the amount determines the probability of predator response. We show that seedlings of a cabbage variety (Brassica oleracea var. capitata, cv Shikidori also show such a response to the density of cabbage white (Pieris rapae larvae and attract more (naive parasitoids (Cotesia glomerata when there are more herbivores on the plant. However, when attacked by diamondback moth (Plutella xylostella larvae, seedlings of the same variety (cv Shikidori release volatiles, the total amount of which is high and constant and thus independent of caterpillar density, and naive parasitoids (Cotesia vestalis of diamondback moth larvae fail to discriminate herbivore-rich from herbivore-poor plants. In contrast, seedlings of another cabbage variety of B. oleracea (var. acephala: kale respond in a dose-dependent manner to the density of diamondback moth larvae and attract more parasitoids when there are more herbivores. Assuming these responses of the cabbage cultivars reflect behaviour of at least some genotypes of wild plants, we provide arguments why the behaviour of kale (B. oleracea var acephala is best interpreted as an honest signaling strategy and that of cabbage cv Shikidori (B. oleracea var capitata as a "cry wolf" signaling strategy, implying a conflict of interest between the plant and the enemies of its herbivores: the plant profits from being visited by the herbivore's enemies, but the latter would be better off by visiting other plants with more herbivores. If so, evolutionary theory on alarm signaling predicts consequences of major interest to students of plant protection, tritrophic systems and communication alike.

Hunting for hiding hosts : the behavioral ecology of the stemborer parasitoid Cotesia flavipes

NARCIS (Netherlands)

Potting, R.P.J.

1996-01-01

Classical biological control involves the introduction of an exotic natural enemy to control an introduced pest species. In 1991 the department of Entomology of the Wageningen Agricultural University started a collaborative project with the International Centre for Insect Physiology and

Study on the Hymenoptera parasitoid associated with Lepidoptera larvae in reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste) São Carlos, SP, Brazil.

Science.gov (United States)

Pereira, A G; Silva, R B; Dias, M M; Penteado-Dias, A M

2015-11-01

The aim of this study was to characterize the local fauna of Hymenoptera parasitoids associated with Lepidoptera larvae in areas of reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP, Brazil). Lepidoptera larvae collected with entomological umbrella were kept in the laboratory until emergence of adults or their parasitoids. From those collected in the agrosilvopastoral system, emerged 267 specimens of hymenopteran parasitoids belonging to 16 genera: Braconidae, Agathidinae (Alabagrus), Braconinae (Bracon), Microgastrinae (Cotesia, Diolcogaster, Glyptapanteles, Pholetesor and Protapanteles), Orgilinae (Orgilus); Ichneumonidae, Campopleginae (Casinaria, Charops and Microcharops); Chalcididae, Chalcidinae (Brachymeria and Conura); Eulophidae, Entedoninae (Horismenus), Eulophinae (Elachertus and Euplectrus). From the Lepidoptera larvae collected in the reforestation, emerged 68 specimens of hymenopteran parasitoids, belonging to 8 genera: Chalcididae, Chalcidinae (Conura); Ichneumonidae, Pimplinae (Neotheronia), Campopleginae (Charops and Microcharops) and Braconidae, Microgastrinae (Apanteles, Diolcogaster, Distatrix, Glyptapanteles and Protapanteles). The results of this study suggest the occurrence of a wide variety of Hymenoptera parasitoids in the studied environments.

Study on the Hymenoptera parasitoid associated with Lepidoptera larvae in reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste São Carlos, SP, Brazil

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A. G. Pereira

Full Text Available Abstract The aim of this study was to characterize the local fauna of Hymenoptera parasitoids associated with Lepidoptera larvae in areas of reforestation and agrosilvopastoral systems at Fazenda Canchim (Embrapa Pecuária Sudeste, São Carlos, SP, Brazil. Lepidoptera larvae collected with entomological umbrella were kept in the laboratory until emergence of adults or their parasitoids. From those collected in the agrosilvopastoral system, emerged 267 specimens of hymenopteran parasitoids belonging to 16 genera: Braconidae, Agathidinae (Alabagrus, Braconinae (Bracon, Microgastrinae (Cotesia, Diolcogaster, Glyptapanteles, Pholetesor and Protapanteles, Orgilinae (Orgilus; Ichneumonidae, Campopleginae (Casinaria, Charops and Microcharops; Chalcididae, Chalcidinae (Brachymeria and Conura; Eulophidae, Entedoninae (Horismenus, Eulophinae (Elachertus and Euplectrus. From the Lepidoptera larvae collected in the reforestation, emerged 68 specimens of hymenopteran parasitoids, belonging to 8 genera: Chalcididae, Chalcidinae (Conura; Ichneumonidae, Pimplinae (Neotheronia, Campopleginae (Charops and Microcharops and Braconidae, Microgastrinae (Apanteles, Diolcogaster, Distatrix, Glyptapanteles and Protapanteles. The results of this study suggest the occurrence of a wide variety of Hymenoptera parasitoids in the studied environments.

Parasitoid complex of Zygaena filipendulae L. (Lepidoptera: Zygaenidae

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Žikić V.

2013-01-01

Full Text Available Caterpillars of Zygaena filipendulae Linnaeus were sampled during May and June in the Sićevo Gorge in southern Serbia. All parasitized larvae were found on grey elm trees (Ulmus canescens. During the short period before metamorphosis of Z. filipendulae, we found the whole specter of parasitoid wasps: Cotesia zygaenarum Marshall (Braconidae, Gelis agilis (Fabricius and Mesochorus velox Holmgren (Ichneumonidae, Elasmus platyedrae Ferrière and Pediobius sp. (Eulophidae, Eupelmus vesicularis (Retzius (Eupelmidae and Brachymeria tibialis (Walker (Chalcididae. Beside hymenopteran parasitoids, we found parasitoid flies from the family Tachinidae, Phryxe nemea (Meigen (Diptera. All 46 observed Z. filipendulae larvae found on grey elm trees were parasitized, but three pupae were found directly on Lotus corniculatus. Two species are newly reported as parasitoids of Z. filipendulae: E. platyedrae and Eupelmus vesicularis and three species (G. agilis, M. velox and E. platyedrae are new to the fauna of Serbia. [Projekat Ministarstva nauke Republike Srbije, br. 43001

Laccase 1 gene from Plutella xylostella (PxLac1) and its functions in humoral immune response.

Science.gov (United States)

Wang, Ze-Hua; Hu, Rong-Min; Ye, Xi-Qian; Huang, Jian-Hua; Chen, Xue-Xin; Shi, Min

Laccase (EC 1.10.3.2) is a phenoloxidase found in many insect species. The Laccase 1 gene from Plutella xylostella (PxLac1) was cloned, and its expression patterns and functions were determined using qPCR and RNAi methods. The results showed that the expression levels of PxLac1 were consistently high in all larval stages, and the most abundant was in the midgut during the 4th instar stage. Moreover, the expression of PxLac1 was up-regulated in response to bacterial infection, and decreased 24 h after being parasitized by Cotesia vestalis. Further analyses indicated that the effect of parasitization on PxLac1 was induced by active C. vestalis Bracovirus (CvBV). Haemocyte-free hemolymph phenoloxidase (PO) activity was suppressed when PxLac1 was treated with RNAi. Our results provide evidence for a connection between the Laccase 1 gene and insect immunity, and revealed that parasitoid polydnavirus suppresses host PO activity via PxLac1 regulation. Copyright © 2018. Published by Elsevier Ltd.

Tritrophic choice experiments with Bt plants, the diamondback moth (Plutella xylostella) and the parasitoid Cotesia plutellae

NARCIS (Netherlands)

Schuler, T.H.; Potting, R.P.J.; Denholm, I.; Clark, S.J.; Clark, A.J.; Stewart, C.N.; Poppy, G.M.

2003-01-01

Parasitoids are important natural enemies of many pest species and are used extensively in biological and integrated control programmes. Crop plants transformed to express toxin genes derived from Bacillus thuringiensis (Bt) provide high levels of resistance to certain pest species, which is likely

Protein discovery: combined transcriptomic and proteomic analyses of venom from the endoparasitoid Cotesia chilonis (Hymenoptera: Brachonidae)

Science.gov (United States)

Background: Many species of endoparasitoid wasps provide biological control services in agroecosystems. Although there is a great deal of information on the ecology and physiology of host/parasitoid interactions, relatively little is known on the protein composition of venom and how specific venom p...

Development of the herbivore Pieris rapae and its endoparasitoid Cotesia rubecula on crucifers of field edges

NARCIS (Netherlands)

Harvey, J.A.; Wagenaar, R.

2006-01-01

Several studies have reported that flowering herbs, which grow naturally or are sown adjacent to agricultural fields, may be an important source of nutrients for natural enemies. Many parasitoids readily feed on plant exudates such as floral nectar, which contain different types of sugars that

Parasitoid dan Parasitisasi Plutella xylostella (L. (Lepidoptera: Yponomeutidae di Sumatera Selatan

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SITI HERLINDA

2005-12-01

Full Text Available Surveys from May 2003 to January 2004 in South Sumatera were conducted to determine parasitoid attacking Plutella xylostella (L. and to estimate P. xylostella parasitization by the parasitoids. The eggs and the larvae of P. xylostella were collected from brassicaceous crops, i.e. mustard, Indian mustard, and cabbage. Six parasitoids found were Trichogrammatoidea cojuangcoi Nagaraja (Hymenoptera: Trichogrammatidae, Cotesia plutellae (Kurdj. (Hymenoptera: Braconidae, Diadegma semiclausum Hellen (Hymenoptera: Ichneumonidae, Oomyzus sokolowskii (Kurdj. (Hymenoptera: Eulophidae, Tetrastichus (Hymenoptera: Eulophidae, and a ceraphronid wasp (unidentified species. Trichogrammatoidea cojuangcoi parasitized P. xylostella eggs, however, the others parasitized the larvae except the ceraphronid wasp. In South Sumatera, the ceraphronid wasp was reported for the first time parasitizing D. semiclausum pupae, and its parasitization reached 6.2%. Oomyzus sokolowskii and Tetrastichus were found in this area for the first time, as well. In the highland, D. semiclausum was the most abundant compared to the others where its parasitization reached 79.2%. In the lowland P. xylostella larvae was mainly attacked by C. plutellae with the parasitization reaching 64.9% In the dry and rainy seasons, the parasitization was mainly exerted by T. cojuangcoi (77.0% and D. semiclausum (79.2%.

Parasitoid and Parasitization of Plutella xylostella (L. (Lepidoptera: Yponomeutidae in South Sumatera

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SITI HERLINDA

2005-12-01

Full Text Available Surveys from May 2003 to January 2004 in South Sumatera were conducted to determine parasitoid attacking Plutella xylostella (L. and to estimate P. xylostella parasitization by the parasitoids. The eggs and the larvae of P. xylostella were collected from brassicaceous crops, i.e. mustard, Indian mustard, and cabbage. Six parasitoids found were Trichogrammatoidea cojuangcoi Nagaraja (Hymenoptera: Trichogrammatidae, Cotesia plutellae (Kurdj. (Hymenoptera: Braconidae, Diadegma semiclausum Hellen (Hymenoptera: Ichneumonidae, Oomyzus sokolowskii (Kurdj. (Hymenoptera: Eulophidae, Tetrastichus (Hymenoptera: Eulophidae, and a ceraphronid wasp (unidentified species. Trichogrammatoidea cojuangcoi parasitized P. xylostella eggs, however, the others parasitized the larvae except the ceraphronid wasp. In South Sumatera, the ceraphronid wasp was reported for the first time parasitizing D. semiclausum pupae, and its parasitization reached 6.2%. Oomyzus sokolowskii and Tetrastichus were found in this area for the first time, as well. In the highland, D. semiclausum was the most abundant compared to the others where its parasitization reached 79.2%. In the lowland P. xylostella larvae was mainly attacked by C. plutellae with the parasitization reaching 64.9%. In the dry and rainy seasons, the parasitization was mainly exerted by T. cojuangcoi (77.0% and D. semiclausum (79.2%.

Hymenopteran parasitoids associated with the banana-skipper Erionota thrax L. (Insecta: Lepidoptera, Hesperiidae in Java, Indonesia

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ERNIWATI

2011-04-01

Full Text Available Erniwati, Ubaidillah R (2011 Hymenopteran parasitoids associated with the banana-skipper Erionota thrax L. (Insecta: Lepidoptera, Hesperiidae in Java, Indonesia. Biodiversitas 12: 76-85. Hymenopteran parasitoids of banana-skipper Erionota thrax L. (Insecta: Lepidoptera, Hesperiidae from Java, Indonesia are reviewed and an illustrated key to 12 species is presented to include Theronia zebra zebra, Xanthopimpla gamsura, Casinaria sp., Charops sp., Cotesia (Apanteles erionotae, Brachymeria lasus, B. thracis, Ooencyrtus pallidipes, Anastatus sp., Pediobius erionotae, Agiommatus sumatraensis and Sympiesis sp. The surveys of the natural enemies of the banana-skipper were conducted in 1990-2006 in several localities in Java. The aim of this study was to assess the native natural enemies of E. thrax, especially the parasitic Hymenoptera. Infested eggs, larvae and pupae of E. thrax were collected and reared in the laboratory. Emerging parasitoids were preserved in both dry mounting and in 80% alcohol for the species identification. Members of families Braconidae, Ichneumonidae, Encyrtidae, Pteromalidae, Chalcididae, Eupelmidae and Eulophidae were recorded as parasitoids of the banana skipper E. thrax from Java, Indonesia. Species distribution and alternative hosts of the parasitoids are presented.

Hostplant suitability and defensive chemistry of the Catalpa sphinx, Ceratomia catalpae.

Science.gov (United States)

Bowers, M Deane

2003-10-01

The growth and survival of the Catalpa sphinx, Ceratomia catalpae (Sphingidae), were measured on five different species of Catalpa: C. bignonioides, C. bungeii, C. fargeseii, C. ovata, and C. speciosa. Larval growth varied significantly among these host plant species; however, survival did not differ. Quantification of the iridoid glycoside content of larvae, pupae, adults, larval frass, and leaves of the larval host plant, C. bignonioides, by gas chromatography showed that leaves contained both catalpol and catalposide; larvae, pupae, and frass contained only catalpol; and the adults contained no detectable iridoid glycosides. Amounts were highest in the larvae and declined in the pupal stage. Very small amounts of catalpol were detected in adults of the parasitoid, Cotesia congregata, and in the silken cocoons. The hemolymph in which the parasitoid larvae grew contained over 50% dry weight catalpol. Larvae of C. catalpae often regurgitate when disturbed. This may serve as a defense against predators. A comparison of the growth of larvae pinched with forceps to induce regurgitation with those that were not so treated showed that larvae that were pinched, and usually regurgitated, grew significantly more slowly than those that were not.

Toxicidade de inseticidas a Diatraea saccharalis (Fabr., 1794) (Lepidoptera:Crambidae) e Cotesia flavipes (Cameron, 1891) (Hymenoptera: Braconidae)

OpenAIRE

Edgar Francisco Gaona Mena

2010-01-01

A magnitude do problema de Diatraea saccharalis (Fabricius) tem aumentado nos últimos anos, principalmente nas culturas de cana-de-açúcar e milho no Brasil. Tradicionalmente, D. saccharalis tem sido controlado com agentes de controle biológico, principalmente na cultura da cana-de-açúcar. No entanto, a intervenção química tem sido necessária para o controle de D. saccharalis em ambas as culturas. Visando estabelecer estratégias proativas para o manejo da resistência de D. saccharalis a inseti...

Parasitoid-host endocrine relations: self-reliance or co-optation?

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Cole, T J; Beckage, N E; Tan, F F; Srinivasan, A; Ramaswamy, S B

2002-12-01

High titers of juvenile hormone (JH) maintain developmental arrest in Manduca sexta larvae parasitized by Cotesia congregata. Parasitized hosts exhibit up to 9.5 times greater amounts of total hemolymph JH (from 0.6+/-0.09 to 2.51+/-0.43ng/ml) compared to non-parasitized controls. Elevated titers are observed throughout the fifth instar, even beyond egression of the parasitoids on day 5. GC-MS analysis revealed that in hemolymph of unparasitized control larvae, JH I is the major homolog and levels of JH III are negligible; in parasitized individuals the amounts of JH I, II, and III rise, and JH III predominates. Neck ligation ensured separation of M. sexta's corpora allata from the posterior section, which contained most of the parasitoids in the infected insects. When the posterior region was sampled, JHs were not detected in the non-parasitzed larvae, but in those parasitized, JH III was found (1.98+/-0.29ng/ml, 24 h post-ligation). JH III was the only homolog produced and secreted by the parasitoid in in vitro culture. This is the first report stating that a parasitoid secretes JH III and may contribute, at least in part, to the circulating titer in the host hemocoel, concurrently promoting host production of JH I and II.

Mating Frequency and Effects on Sex Ratio in Female Parasitoids of xanthopimpla Stemmator (Thunberg). Implications in biological control Programmes

International Nuclear Information System (INIS)

Gitau, C.W.

2002-01-01

Cereals, especially maize and sorghum are the most important field crops in Africa. classical biological Control is a management strategy that employs natural enemies against exotic pests on cereal crops. The method has been used against Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), an introduced pest of maize, using the larval parasitoid cotesia flavipes (Cameron). However, C. flavipes is not able to attack all stem borer species in targeted areas. to complement its work, Xanthopimpla stemmator has successfully been established in Mauritius on Chilo sacchariphagus (Bojer). It is a common phenomenon for haplo-diploid parasitoids to give rise to male progeny when insemination does not take place. Mating becomes important to the parasitoid population since a male biased sex ratio can bring about collapse of the population. The aim of this study was to determine wether xanthopimpla stemmator females mat more than once and wether sex ratio of progeny is affected by multiple mating in female X. stemmator. The female showed a tendency to mate once. Multiple mating did not have any significant effect on either sex ratio or longevity. More males were produced in multiple mated females than once mated females.The effect of multiple mating in X. stemmator on sex ratio in relation to biocontrol programmes are discussed

Long-distance assessment of patch profitability through volatile infochemicals by the parasitoids Cotesia glomerata and C. rubecula (Hymenoptera: Braconidae).

NARCIS (Netherlands)

Geervliet, J.B.F.; Ariens, S.; Dicke, M.; Vet, L.E.M.

1998-01-01

Using two closely related larval parasitoids (Cotesiaspp.) ofPieriscaterpillars we tested the hypothesis that parasitoids are capable of assessing patch profitability from a distance by showing differential responses to odors from plants infested with different host densities. We furthermore tested

Plant surface wax affects parasitoid's response to host footprints

Science.gov (United States)

Rostás, Michael; Ruf, Daniel; Zabka, Vanessa; Hildebrandt, Ulrich

2008-10-01

The plant surface is the substrate upon which herbivorous insects and natural enemies meet and thus represents the stage for interactions between the three trophic levels. Plant surfaces are covered by an epicuticular wax layer which is highly variable depending on species, cultivar or plant part. Differences in wax chemistry may modulate ecological interactions. We explored whether caterpillars of Spodoptera frugiperda, when walking over a plant surface, leave a chemical trail (kairomones) that can be detected by the parasitoid Cotesia marginiventris. Chemistry and micromorphology of cuticular waxes of two barley eceriferum wax mutants ( cer-za.126, cer-yp.949) and wild-type cv. Bonus (wt) were assessed. The plants were then used to investigate potential surface effects on the detectability of caterpillar kairomones. Here we provide evidence that C. marginiventris responds to chemical footprints of its host. Parasitoids were able to detect the kairomone on wild-type plants and on both cer mutants but the response to cer-yp.949 (reduced wax, high aldehyde fraction) was less pronounced. Experiments with caterpillar-treated wt and mutant leaves offered simultaneously, confirmed this observation: no difference in wasp response was found when wt was tested against cer-za.126 (reduced wax, wt-like chemical composition) but wt was significantly more attractive than cer-yp.949. This demonstrates for the first time that the wax layer can modulate the detectability of host kairomones.

Eliminating host-mediated effects demonstrates Bt maize producing Cry1F has no adverse effects on the parasitoid Cotesia marginiventris

Science.gov (United States)

The fall armyworm, Spodoptera frugiperda, is an important pest of maize in the United States and many tropical areas in the western hemisphere. In 2001, Herculex I ® (Cry1F) maize was commercially planted in the United States to control Lepidoptera, including S. frugiperda. In 2006, a population of ...

Herbivore-induced volatile production by Arabidopsis thaliana leads to attraction of the parasitoid Cotesia rubecula: chemical, behavioral, and gene-expression analysis

NARCIS (Netherlands)

Poecke, R.M.P.; Posthumus, M.A.; Dicke, M.

2001-01-01

Many plant species defend themselves against herbivorous insects indirectly by producing volatiles in response to herbivory. These volatiles attract carnivorous enemies of the herbivores. Research on the model plant Arabidopsis thaliana (L.) Heynh. has contributed considerably to the unraveling of

Critical electrolyte concentration of silk gland chromatin of the sugarcane borer Diatraea saccharalis, induced using agrochemicals.

Science.gov (United States)

Santos, S A; Fermino, F; Moreira, B M T; Araujo, K F; Falco, J R P; Ruvolo-Takasusuki, M C C

2014-09-29

The sugarcane borer Diatraea saccharalis is widely known as the main pest of sugarcane crop, causing increased damage to the entire fields. Measures to control this pest involve the use of chemicals and biological control with Cotesia flavipes wasps. In this study, we evaluated the insecticides fipronil (Frontline; 0.0025%), malathion (Malatol Bio Carb; 0.4%), cipermetrina (Galgotrin; 10%), and neem oil (Natuneem; 100%) and the herbicide nicosulfuron (Sanson 40 SC; 100%) in the posterior region silk glands of 3rd- and 5th-instar D. saccharalis by studying the variation in the critical electrolyte concentration (CEC). Observations of 3rd-instar larvae indicated that malathion, cipermetrina, and neem oil induced increased chromatin condensation that may consequently disable genes. Tests with fipronil showed no alteration in chromatin condensation. With the use of nicosulfuron, there was chromatin and probable gene decompaction. In the 5th-instar larvae, the larval CEC values indicated that malathion and neem oil induced increased chromatin condensation. The CEC values for 5th-instar larvae using cipermetrina, fipronil, and nicosulfuron indicated chromatin unpacking. These observations led us to conclude that the quantity of the pesticide does not affect the mortality of these pests, can change the conformation of complexes of DNA, RNA, and protein from the posterior region of silk gland cells of D. saccharalis, activating or repressing the expression of genes related to the defense mechanism of the insect and contributing to the selection and survival of resistant individuals.

Mortality of Plutella xylostella (Lepidoptera, Plutellidae by parasitoids in the Province of Santa Fe, Argentina

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Isabel Bertolaccini

2011-09-01

Full Text Available Mortality of Plutella xylostella (Lepidoptera, Plutellidae by parasitoids in the Province of Santa Fe, Argentina. Plutella xylostella (Linnaeus, 1758 (Lepidoptera, Plutellidae larvae cause severe economic damage on cabbage, Brassica oleracea L. variety capitata (Brassicaceae, in the horticultural fields in the Province of Santa Fe, Argentina. Overuse of broad spectrum insecticides affects the action of natural enemies of this insect on cabbage. The objectives of this work were to identify the parasitoids of P. xylostella and to determine their influence on larva and pupa mortality. Weekly collections of larvae and pupae were randomly conducted in cabbage crops during spring 2006 and 2007. The immature forms collected were classified according to their developmental stage: L1 and L2 (Ls = small larvae, L3 (Lm = medium larvae, L4 (Ll = large larvae, pre-pupae and pupae (P. Each individual was observed daily in the laboratory until the adult pest or parasitoid emergence. We identified parasitoids, the number of instar and the percentage of mortality of P. xylostella for each species of parasitoid. Parasitoids recorded were: Diadegma insulare (Cresson, 1875 (Hymenoptera, Ichneumonidae, Oomyzus sokolowskii (Kurdjumov, 1912 (Hymenoptera, Eulophidae, Cotesia plutellae (Kurdjumov, 1912 (Hymenoptera, Braconidae and an unidentified species of Chalcididae (Hymenoptera. Besides parasitoids, an unidentified entomopathogenic fungus was also recorded in 2006 and 2007. In 2006, the most successful parasitoids were D. insulare and O. sokolowskii, while in 2007 only D. insulare exerted a satisfactory control and it attacked the early instars of the pest.

Priming of cowpea volatile emissions with defense inducers enhances the plant's attractiveness to parasitoids when attacked by caterpillars.

Science.gov (United States)

Sobhy, Islam S; Bruce, Toby Ja; Turlings, Ted Cj

2018-04-01

The manipulation of herbivore-induced volatile organic compounds (HI-VOCs) via the application of the inducers benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) and laminarin (β-1,3-glucan) is known to enhance the attractiveness of caterpillar-damaged cotton and maize plants to parasitoids. To test if this is also the case for legumes, we treated cowpea (Vigna unguiculata var. unguiculata) with these inducers and studied the effects on HI-VOC emissions and the attraction of three generalist endoparasitoids. After the inducers had been applied and the plants subjected to either real or mimicked herbivory by Spodoptera littoralis caterpillars, females of the parasitoids Campoletis sonorensis and Microplitis rufiventris showed a strong preference for BTH-treated plants, whereas Cotesia females were strongly attracted to both BTH- and laminarin-treated plants with real or mimicked herbivory. Treated plants emitted more of certain HI-VOCs, but considerably less indole and linalool and less of several sesquiterpenes. Multivariate data analysis revealed that enhanced wasp attraction after treatment was correlated with high relative concentrations of nonanal, α-pinene, (E)-β-ocimene and (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), and with low relative concentrations of indole, (S)-linalool and (E)-β-farnesene. Inducer treatments had no significant effect on leaf consumption by the caterpillars. Our findings confirm that treating cowpea plants with inducers can enhance their attractiveness to biological control agents. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

KEMELIMPAHAN DAN KERAGAMAN JENIS PARASITOID HAMA PENGGULUNG DAUN PISANG ERIONOTA THRAX L. DI KABUPATEN LAMPUNG SELATAN

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Lestari Wibowo

2015-03-01

Full Text Available The abundance and diversity of the parasitoid of banana leaf skipper pest (Erionota thrax L. in South Lampung Regency. This research was conducted to determine the abundance, diversity, and parasitation ability of several parasitoids of the banana skipper or banana leafroller (Erionota thrax in South Lampung Regency. This research was carried out with a survey method by taking out samples of larvae and pupae of E. thrax in the District of Natar, Jati Agung, and Tanjung Bintang, South Lampung. Results of the survey showed that there were 8 types of parasitoids recovered from larvae or pupae of E. thrax, i.e. Brachymeria lasus (Chalcididae: Hymenoptera, B. thracis (Chalcididae: Hymenoptera, Charops sp. (Ichneumonidae: Hymenoptera, Casinaria sp. (Ichneumonidae: Hymenoptera, Xanthopimpla sp. (Ichneumonidae: Hymenoptera, Cotesia erionotae (Braconidae: Hymenoptera, and two parasitoids Diptera (Tachinidae and Sarcophagidae. The highest abundance of parasitoid was found in Tanjung Bintang with 171 parasitoids (index of diversity (H’ = 1.0256 and index of evenness (E = 0.5724. In Natar District, the abundance of parasitoid was 63 parasitoids, but it had a greater H’ value (1.4396 and E-value (0.7398. Meanwhile, in Jati Agung District, the abundance of parasitoid was 56 individuals but the value of H’ was also high, which was 1.012 with the value of E of 0.6064. The percentages of parasitation to the larvae and pupae E. thrax were 55.01% (Tanjung Bintang District, 31.68% (Natar District and 33.34% (Jati Agung District.

DNA-based confirmation that the parasitic wasp Cotesia glomerata (Braconidae, Hymenoptera) is a new threat to endemic butterflies of the Canary Islands

Czech Academy of Sciences Publication Activity Database

Lozan, Aurel; Monaghan, M. T.; Spitzer, Karel; Jaroš, Josef; Žurovcová, Martina; Brož, V.

2008-01-01

Roč. 9, č. 6 (2008), s. 1431-1437 ISSN 1566-0621 R&D Projects: GA AV ČR 1QS500070505 Grant - others:EU SYNTHESIS(BE) GB-TAF-2063; UK Biotechnology and Biological Sciences Research Council(GB) BBS/B/04358 Institutional research plan: CEZ:AV0Z50070508 Keywords : alien parasitoids * threatened butterflies * laurel forests Subject RIV: EH - Ecology, Behaviour Impact factor: 2.408, year: 2008

Gamma irradiation on canola seeds affects herbivore-plant and host-parasitoid interactions

International Nuclear Information System (INIS)

Akandeh, M.; Kocheili, F.; Rasekh, A.; Soufbaf, M.

2017-01-01

As an agricultural modernization, gamma irradiation is an important method for enhancing crop yield and quality. Nevertheless, its use can alter other plant traits such as nutrition and resistance to different biotic/abiotic stresses that consequently affect plant-insect interactions. A tritrophic system was utilized based on two canola mutant lines produced through gamma irradiation (RGS 8-1 and Talaye 8-3). Plutella xylostella (L.), as a worldwide pest of Brassicaceae and Cotesia vestalis (Holiday) as a key biocontrol agent of P. xylostella were examined for the potential indirect effects of canola seed irradiation on the experimental insects' performance when acting on the respective mutant lines. This study showed that physical mutation did not affect plant nitrogen and herbivore-damaged total phenolics; however, phenolic compounds showed greater concentration in damaged leaves than undamaged leaves of both mutant and control plants. The relative growth rate and pupal weight of P. xylostella reared on RGS 8-1 were significantly higher than those reared on the control RGS. There was no significant difference by performance parameters of the parasitoid, C. vestalis, including total pre-oviposition period, adult longevity, adult fresh body weight of males and females, pupal weight, forewing area, and total longevity of both sexes on tested canola cultivars in comparison with their mutant lines. Life table parameters of C. vestalis on mutant lines of both cultivars, RGS and Talaye, were not significantly different from their control treatments. Comprehensive studies should be conducted to find out the mechanisms under which gamma rays affect plant-insect interactions. (author)

The Gastropod Menace: Slugs on Brassica Plants Affect Caterpillar Survival through Consumption and Interference with Parasitoid Attraction.

Science.gov (United States)

Desurmont, Gaylord A; Zemanova, Miriam A; Turlings, Ted C J

2016-03-01

Terrestrial molluscs and insect herbivores play a major role as plant consumers in a number of ecosystems, but their direct and indirect interactions have hardly been explored. The omnivorous nature of slugs makes them potential disrupters of predator-prey relationships, as a direct threat to small insects and through indirect, plant-mediated effects. Here, we examined the effects of the presence of two species of slugs, Arion rufus (native) and A. vulgaris (invasive) on the survivorship of young Pieris brassicae caterpillars when feeding on Brassica rapa plants, and on plant attractiveness to the main natural enemy of P. brassicae, the parasitoid Cotesia glomerata. In two separate predation experiments, caterpillar mortality was significantly higher on plants co-infested with A. rufus or A. vulgaris. Moreover, caterpillar mortality correlated positively with slug mass and leaf consumption by A. vulgaris. At the third trophic level, plants infested with slugs and plants co-infested with slugs and caterpillars were far less attractive to parasitoids than plants damaged by caterpillars only, independently of slug species. Chemical analyses confirmed that volatile emissions, which provide foraging cues for parasitoids, were strongly reduced in co-infested plants. Our study shows that the presence of slugs has the potential to affect insect populations, directly via consumptive effects, and indirectly via changes in plant volatiles that result in a reduced attraction of natural enemies. The fitness cost for P. brassicae imposed by increased mortality in presence of slugs may be counterbalanced by the benefit of escaping its parasitoids.

Plant strengtheners enhance parasitoid attraction to herbivore-damaged cotton via qualitative and quantitative changes in induced volatiles.

Science.gov (United States)

Sobhy, Islam S; Erb, Matthias; Turlings, Ted C J

2015-05-01

Herbivore-damaged plants release a blend of volatile organic compounds (VOCs) that differs from undamaged plants. These induced changes are known to attract the natural enemies of the herbivores and therefore are expected to be important determinants of the effectiveness of biological control in agriculture. One way of boosting this phenomenon is the application of plant strengtheners, which has been shown to enhance parasitoid attraction in maize. It is unclear whether this is also the case for other important crops. The plant strengtheners BTH [benzo (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester] and laminarin were applied to cotton plants, and the effects on volatile releases and the attraction of three hymenopteran parasitoids, Cotesia marginiventris, Campoletis sonorensis and Microplitis rufiventris, were studied. After treated and untreated plants were induced by real or simulated caterpillar feeding, it was found that BTH treatment increased the attraction of the parasitoids, whereas laminarin had no significant effect. BTH treatment selectively increased the release of two homoterpenes and reduced the emission of indole, the latter of which had been shown to interfere with parasitoid attraction in earlier studies. Canonical variate analyses of the data show that the parasitoid responses were dependent on the quality rather than the quantity of volatile emission in this tritrophic interaction. Overall, these results strengthen the emerging paradigm that induction of plant defences with chemical elicitors such as BTH could provide a sustainable and environmentally friendly strategy for biological control of pests by enhancing the attractiveness of cultivated plants to natural enemies of insect herbivores. © 2014 Society of Chemical Industry.

A survey of hymenopteran parasitoids of forest macrolepidoptera in the central Appalachians.

Science.gov (United States)

Petrice, T R; Strazanac, J S; Butler, L

2004-04-01

In 1995 and 1996, we conducted a study of the hymenopteran parasitoids of macrolepidopteran larvae in the George Washington National Forest (GWNF), Augusta County, Virginia, and the Monongahela National Forest (MNF), Pocahontas County, West Virginia. Macrolepidopteran larvae were collected from canopy foliage and from under canvas bands placed around tree boles. A total of 115 macrolepidopteran species and 5,235 individual larvae were reared. Forty-two percent (2,221) of the larvae were gypsy moth, Lymantria dispar (L.) (Lymantriidae). A total of 43 primary and secondary (hyperparasitoid) hymenopteran parasitoid species were reared from 46 macrolepidopteran species. Hymenopteran families represented included Ichneumonidae (23 species), Braconidae (19), Eulophidae (6), Perilampidae (1), and Trigonalidae (1). We reared 41 and 28 parasitoid species from the GWNF and the MNF, respectively, with 19 species reared from both forests. Many parasitoid species were collected infrequently, suggesting that they are relatively rare on the sampled hosts. The introduced species Cotesia melanoscela (Ratzeburg) (Braconidae), and Euplectrus bicolor (Swederus) (Eulophidae) were among the most commonly reared parasitoids, the latter reared from native hosts. The four most commonly reared native parasitoids were Meteorus hyphantriae, Riley (Braconidae), Microplitis near hyphantriae (Ashmead) (Braconidae), Aleiodes preclarus Marsh & Shaw, and Euplectrus maculiventris (Westwood) (Eulophidae). A total of 53 new hymenopteran parasitoid-macrolepidopteran host records were documented. Results from this study will be used to evaluate long-term treatment effects of regional applications of Bacillus thuringiensis kurstaki, and the gypsy moth fungus Entomophaga maimaiga Humber, Shimazu & Soper on hymenopteran parasitoids of macrolepidopteran larvae.

Gamma irradiation on canola seeds affects herbivore-plant and host-parasitoid interactions

Energy Technology Data Exchange (ETDEWEB)

Akandeh, M.; Kocheili, F.; Rasekh, A. [Dept. of Entomology, Shahid Chamran Univ of Ahvaz (Iran, Islamic Republic of); Soufbaf, M., E-mail: msoufbaf@nrcam.org [Agricultural, Medical and Industrial Research School, Karaj (Iran, Islamic Republic of)

2017-06-15

As an agricultural modernization, gamma irradiation is an important method for enhancing crop yield and quality. Nevertheless, its use can alter other plant traits such as nutrition and resistance to different biotic/abiotic stresses that consequently affect plant-insect interactions. A tritrophic system was utilized based on two canola mutant lines produced through gamma irradiation (RGS 8-1 and Talaye 8-3). Plutella xylostella (L.), as a worldwide pest of Brassicaceae and Cotesia vestalis (Holiday) as a key biocontrol agent of P. xylostella were examined for the potential indirect effects of canola seed irradiation on the experimental insects' performance when acting on the respective mutant lines. This study showed that physical mutation did not affect plant nitrogen and herbivore-damaged total phenolics; however, phenolic compounds showed greater concentration in damaged leaves than undamaged leaves of both mutant and control plants. The relative growth rate and pupal weight of P. xylostella reared on RGS 8-1 were significantly higher than those reared on the control RGS. There was no significant difference by performance parameters of the parasitoid, C. vestalis, including total pre-oviposition period, adult longevity, adult fresh body weight of males and females, pupal weight, forewing area, and total longevity of both sexes on tested canola cultivars in comparison with their mutant lines. Life table parameters of C. vestalis on mutant lines of both cultivars, RGS and Talaye, were not significantly different from their control treatments. Comprehensive studies should be conducted to find out the mechanisms under which gamma rays affect plant-insect interactions. (author)

Phylogeny of economically important insect pests that infesting several crops species in Malaysia

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Ghazali, Siti Zafirah; Zain, Badrul Munir Md.; Yaakop, Salmah

2014-09-01

This paper reported molecular data on insect pests of commercial crops in Peninsular Malaysia. Fifteen insect pests (Metisa plana, Calliteara horsefeldii, Cotesia vestalis, Bactrocera papayae, Bactrocera carambolae, Bactrocera latifrons, Conopomorpha cramella, Sesamia inferens, Chilo polychrysa, Rhynchophorus vulneratus, and Rhynchophorus ferrugineus) of nine crops were sampled (oil palm, coconut, paddy, cocoa, starfruit, angled loofah, guava, chili and mustard) and also four species that belong to the fern's pest (Herpetogramma platycapna) and storage and rice pests (Tribolium castaneum, Oryzaephilus surinamensis and Cadra cautella). The presented phylogeny summarized the initial phylogenetic hypothesis, which concerning by implementation of the economically important insect pests. In this paper, phylogenetic relationships among 39 individuals of 15 species that belonging to three orders under 12 genera were inferred from DNA sequences of mitochondrial marker, cytochrome oxidase subunit I (COI) and nuclear marker, ribosomal DNA 28S D2 region. The phylogenies resulted from the phylogenetic analyses of both genes are relatively similar, but differ in the sequence of evolution. Interestingly, this most recent molecular data of COI sequences data by using Bayesian Inference analysis resulted a more-resolved phylogeny that corroborated with traditional hypotheses of holometabolan relationships based on traditional hypotheses of holometabolan relationships and most of recently molecular study compared to 28S sequences. This finding provides the information on relationships of pests species, which infested several crops in Malaysia and also estimation on Holometabola's order relationships. The identification of the larval stages of insect pests could be done accurately, without waiting the emergence of adults and supported by the phylogenetic tree.

Eco-toxicological risk and impact of pesticides on important parasitoids of cabbage butterflies in cruciferous ecosystem.

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Firake, D M; Thubru, D P; Behere, G T

2017-02-01

Eco-toxicological risk and impact of pesticides was estimated on three important parasitoids of butterflies viz., Hyposoter ebeninus, Cotesia glomerata and Pteromalus puparum. Four commonly used pesticides were evaluated using standard protocol (of IOBC/WPRS-group). In laboratory tests, the survival of the female wasps decreased significantly on fresh contact and ingestion of deltamethrin, spinosad and azadirachtin; whereas Bacillus thuringiensis var kurstaki (Btk) was found harmless pesticide. Under semi-field conditions, parasitoid mortality decreased significantly on fresh contact with the pesticides. Although, at 72 h after treatment, spinosad and deltamethrin were found harmful (Class-IV) and azadirachtin was moderately harmful (Class-III), whereas Btk was harmless (Class-I). Furthermore, 15-day-old residues of pesticides (except deltamethrin) were harmless to all parasitoid species under semi-field conditions. Notably, adult emergence and pupal duration in pesticide-treated cocoons were not significantly affected; however, their survival decreased after emergence except in Btk. The contact and oral toxicity trends of the pesticides were almost similar for three species of parasitoid females and pupae; however little variability was observed in toxicity to the host caterpillars parasitized by H. ebeninus (HCPHE) and C. glomerata (HCPCG). In semi-field tests, fresh residues of all the pesticides were harmful to HCPHE and HCPCG. However, action of Btk was slightly delayed and toxicity was rather low for HCPCG. In 15-day-old residues, deltamethrin and azadirachtin were slightly harmful to the parasitized caterpillars, whereas those of Btk and spinosad were harmless. Since, Btk appeared to be safe for parasitoids; it could be used for managing cabbage butterflies in brassicaceous crops. Copyright © 2016 Elsevier Ltd. All rights reserved.

Characterization of joining sites of a viral histone H4 on host insect chromosomes.

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Sunil Kumar

Full Text Available A viral histone H4 (CpBV-H4 is encoded in a polydnavirus, Cotesia plutellae bracovirus (CpBV. It plays a crucial role in parasitism of an endoparasitoid wasp, C. plutellae, against diamondback moth, Plutella xylostella, by altering host gene expression in an epigenetic mode by its N-terminal tail after joining host nucleosomes. Comparative transcriptomic analysis between parasitized and nonparasitized P. xylostella by RNA-Seq indicated that 1,858 genes were altered at more than two folds in expression levels at late parasitic stage, including 877 up-regulated genes and 981 down-regulated genes. Among parasitic factors altering host gene expression, CpBV-H4 alone explained 16.3% of these expressional changes. To characterize the joining sites of CpBV-H4 on host chromosomes, ChIP-Seq (chromatin immunoprecipitation followed by deep sequencing was applied to chromatins extracted from parasitized larvae. It identified specific 538 ChIP targets. Joining sites were rich (60.2% in AT sequence. Almost 40% of ChIP targets included short nucleotide repeat sequences presumably recognizable by transcriptional factors and chromatin remodeling factors. To further validate these CpBV-H4 targets, CpBV-H4 was transiently expressed in nonparasitized host at late larval stage and subjected to ChIP-Seq. Two kinds of ChIP-Seqs shared 51 core joining sites. Common targets were close (within 1 kb to genes regulated at expression levels by CpBV-H4. However, other host genes not close to CpBV-H4 joining sites were also regulated by CpBV-H4. These results indicate that CpBV-H4 joins specific chromatin regions of P. xylostella and controls about one sixth of the total host genes that were regulated by C. plutellae parasitism in an epigenetic mode.

Translational Control of Host Gene Expression by a Cys-Motif Protein Encoded in a Bracovirus.

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Eunseong Kim

Full Text Available Translational control is a strategy that various viruses use to manipulate their hosts to suppress acute antiviral response. Polydnaviruses, a group of insect double-stranded DNA viruses symbiotic to some endoparasitoid wasps, are divided into two genera: ichnovirus (IV and bracovirus (BV. In IV, some Cys-motif genes are known as host translation-inhibitory factors (HTIF. The genome of endoparasitoid wasp Cotesia plutellae contains a Cys-motif gene (Cp-TSP13 homologous to an HTIF known as teratocyte-secretory protein 14 (TSP14 of Microplitis croceipes. Cp-TSP13 consists of 129 amino acid residues with a predicted molecular weight of 13.987 kDa and pI value of 7.928. Genomic DNA region encoding its open reading frame has three introns. Cp-TSP13 possesses six conserved cysteine residues as other Cys-motif genes functioning as HTIF. Cp-TSP13 was expressed in Plutella xylostella larvae parasitized by C. plutellae. C. plutellae bracovirus (CpBV was purified and injected into non-parasitized P. xylostella that expressed Cp-TSP13. Cp-TSP13 was cloned into a eukaryotic expression vector and used to infect Sf9 cells to transiently express Cp-TSP13. The synthesized Cp-TSP13 protein was detected in culture broth. An overlaying experiment showed that the purified Cp-TSP13 entered hemocytes. It was localized in the cytosol. Recombinant Cp-TSP13 significantly inhibited protein synthesis of secretory proteins when it was added to in vitro cultured fat body. In addition, the recombinant Cp-TSP13 directly inhibited the translation of fat body mRNAs in in vitro translation assay using rabbit reticulocyte lysate. Moreover, the recombinant Cp-TSP13 significantly suppressed cellular immune responses by inhibiting hemocyte-spreading behavior. It also exhibited significant insecticidal activities by both injection and feeding routes. These results indicate that Cp-TSP13 is a viral HTIF.

Species and cultivar influences on survival and parasitism of fall armyworm.

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Braman, S K; Duncan, R R; Hanna, W W; Engelke, M C

2004-12-01

Interactions between host plant resistance and biological control may benefit or hinder pest management efforts. Turfgrass cultivars have rarely been tested for extrinsic resistance characteristics such as occurrence and performance of beneficial arthropods on plant genotypes with resistance to known turf pests. Parasitism of fall armyworm, Spodoptera frugiperda (J.E. Smith), among six turfgrass genotypes was evaluated. The six grasses tested [Sea Isle-1 and 561-79 seashore paspalum, Paspalum vaginatum Swartz; TifSport and TifEagle hybrid Bermuda grass, Cynodon dactylon (L.) x C. transvaalensis (Burtt-Davy); and Cavalier and Palisades zoysiagrass, Zoysia japonica von Steudel and Z. matrella (L.) Merrill, respectively] represented a range in resistance to S. frugiperda. Differential recovery of larvae released as first instars reflected this gradient in resistance of Cavalier > or = Palisades > or = TifSport = TifEagle > or = 561- = Sea Isle-1 Larval recovery (percentage of initial number released) was greatest in May, less in July and August, and least in October, probably reflecting the increase in activity of on-site predators and disease pressure. Parasitism of the fall armyworm by the braconid Aleiodes laphygmae Viereck varied among turfgrass genotypes. Parasitism was greatest during July. In total, 20,400 first instars were placed in the field; 2,368 were recovered; 468 parasitoids were subsequently reared; 92.2% were A. laphygmae. In the field, the greatest percentage of reduction in S. frugiperda larvae by A. laphygmae occurred on the armyworm-susceptible seashore paspalums (51.9% on Sea Isle-1 in July). Cotesia marginiventris Cresson and Meteorus sp. also were reared from collected larvae. No parasitoids were reared from larvae collected from resistant Cavalier zoysiagrass. A. laphygmae and C. marginiventris were reared from larvae collected from the other five grass cultivars. No parasitoids of older larvae or pupae were observed.

Immunoevasive protein (IEP)-containing surface layer covering polydnavirus particles is essential for viral infection.

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Furihata, Shunsuke; Tanaka, Kohjiro; Ryuda, Masasuke; Ochiai, Masanori; Matsumoto, Hitoshi; Csikos, Gyorge; Hayakawa, Yoichi

2014-01-01

Polydnaviruses (PDVs) are unique symbiotic viruses associated with parasitoid wasps: PDV particles are injected into lepidopteran hosts along with the wasp eggs and express genes that interfere with aspects of host physiology such as immune defenses and development. Recent comparative genomic studies of PDVs have significantly improved our understanding of their origin as well as the genome organization. However, the structural features of functional PDV particles remain ambiguous. To clear up the structure of Cotesia kariyai PDV (CkPDV) particles, we focused on immunoevasive protein (IEP), which is a mediator of immunoevasion by the wasp from the encapsulation reaction of the host insect's hemocytes, because it has been demonstrated to be present on the surface of the virus particle. We discovered that IEP tends to polymerize and constitutes a previously unidentified thin surface layer covering CkPDV particles. This outermost surface layer looked fragile and was easily removed from CkPVD particles by mechanical stressors such as shaking, which prevented CkPDV from expressing the encoded genes in the host target tissues such as fat body or hemocytes. Furthermore, we detected IEP homologue gene expression in the wasp's venom reservoirs, implying IEP has another unknown biological function in the wasp or parasitized hosts. Taken together, the present results demonstrated that female C. kariyai wasps produce the fragile thin layer partly composed of IEP to cover the outer surfaces of CkPDV particles; otherwise, they cannot function as infectious agents in the wasp's host. The fact that IEP family proteins are expressed in both venom reservoirs and oviducts suggests an intimate relationship between both tissues in the development of the parasitism strategy of the wasp. Copyright © 2013 Elsevier Inc. All rights reserved.

Bestrijding schadelijke rupsensoorten in de glastuinbouw met sluipwespen : toetsing van Cotesia vanessae in het laboratorium en toetsing van Meteorus gyrator tegen turkse mot (Chrysodeixis chalcites) in komkommer

NARCIS (Netherlands)

Bloemhard, C.M.J.; Haaring, M.A.

2005-01-01

Zowel in groente- als sierteelten onder glas komen rupsen voor uit de families Noctuidae, Tortricidae en Pyralidae. Bestaande chemische middelen of biologische bestrijders voldoen vaak niet. Uit literatuuronderzoek zijn een aantal sluipwespsoorten gekomen die kandidaat zijn voor de bestrijding van

Olfactory responses of Plutella xylostella natural enemies to host pheromone, larval frass, and green leaf cabbage volatiles.

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Reddy, G V P; Holopainen, J K; Guerrero, A

2002-01-01

The parasitoids Trichogramma chilonis (Hymenoptera: Trichogrammatidae) and Cotesia plutellae (Hymenoptera: Braconidae), and the predator Chrysoperla carnea (Neuroptera: Chrysopidae), are potential biological control agents for the diamondback moth, Plutella xylostella (Lepidoptera: Yponomeutidae). We present studies on the interactions between these bioagents and various host-associated volatiles using a Y olfactometer. T chilonis was attracted to a synthetic pheromone blend (Z11-16:Ald, Z11-16:Ac, and Z11-16:OH in a 1:1:0.01 ratio), to Z11-16:Ac alone, and to a 1:1 blend of Z11-16:Ac and Z11-16:Ald. C. plutellae responded to the blend and to Z11-16:Ac and Z11-16:Ald. Male and female C. carnea responded to the blend and to a 1:1 blend of the major components of the pheromone, although no response was elicited by single compounds. Among the four host larval frass volatiles tested (dipropyl disulfide, dimethyl disulfide, allyl isothiocyanate, and dimethyl trisulfide), only allyl isothiocyanate elicited significant responses in the parasitoids and predator, but C. plutellae and both sexes of C. carnea did respond to all four volatiles. Among the green leaf volatiles of cabbage (Brassica oleracea subsp. capitata), only Z3-6:Ac elicited significant responses from T. chilonis, C. plutellae, and C. carnea, but C. plutellae also responded to E2-6:Ald and Z3-6:OH. When these volatiles were blended with the pheromone, the responses were similar to those elicited by the pheromone alone, except for C. carnea males, which had an increased response. The effect of temperature on the response of the biological agents to a mixture of the pheromone blend and Z3-6:Ac was also studied. T. chilonis was attracted at temperatures of 25-35 degrees C, while C. plutellae and C. carnea responded optimally at 30-35 degrees C and 20-25 degrees C, respectively. These results indicate that the sex pheromone and larval frass volatiles from the diamondback moth, as well as volatile compounds from

Comparative mitogenomics of Braconidae (Insecta: Hymenoptera) and the phylogenetic utility of mitochondrial genomes with special reference to Holometabolous insects

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2010-01-01

Background Animal mitochondrial genomes are potential models for molecular evolution and markers for phylogenetic and population studies. Previous research has shown interesting features in hymenopteran mitochondrial genomes. Here, we conducted a comparative study of mitochondrial genomes of the family Braconidae, one of the largest families of Hymenoptera, and assessed the utility of mitochondrial genomic data for phylogenetic inference at three different hierarchical levels, i.e., Braconidae, Hymenoptera, and Holometabola. Results Seven mitochondrial genomes from seven subfamilies of Braconidae were sequenced. Three of the four sequenced A+T-rich regions are shown to be inverted. Furthermore, all species showed reversal of strand asymmetry, suggesting that inversion of the A+T-rich region might be a synapomorphy of the Braconidae. Gene rearrangement events occurred in all braconid species, but gene rearrangement rates were not taxonomically correlated. Most rearranged genes were tRNAs, except those of Cotesia vestalis, in which 13 protein-coding genes and 14 tRNA genes changed positions or/and directions through three kinds of gene rearrangement events. Remote inversion is posited to be the result of two independent recombination events. Evolutionary rates were lower in species of the cyclostome group than those of noncyclostomes. Phylogenetic analyses based on complete mitochondrial genomes and secondary structure of rrnS supported a sister-group relationship between Aphidiinae and cyclostomes. Many well accepted relationships within Hymenoptera, such as paraphyly of Symphyta and Evaniomorpha, a sister-group relationship between Orussoidea and Apocrita, and monophyly of Proctotrupomorpha, Ichneumonoidea and Aculeata were robustly confirmed. New hypotheses, such as a sister-group relationship between Evanioidea and Aculeata, were generated. Among holometabolous insects, Hymenoptera was shown to be the sister to all other orders. Mecoptera was recovered as the

Comparative mitogenomics of Braconidae (Insecta: Hymenoptera and the phylogenetic utility of mitochondrial genomes with special reference to Holometabolous insects

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Shi Min

2010-06-01

Full Text Available Abstract Background Animal mitochondrial genomes are potential models for molecular evolution and markers for phylogenetic and population studies. Previous research has shown interesting features in hymenopteran mitochondrial genomes. Here, we conducted a comparative study of mitochondrial genomes of the family Braconidae, one of the largest families of Hymenoptera, and assessed the utility of mitochondrial genomic data for phylogenetic inference at three different hierarchical levels, i.e., Braconidae, Hymenoptera, and Holometabola. Results Seven mitochondrial genomes from seven subfamilies of Braconidae were sequenced. Three of the four sequenced A+T-rich regions are shown to be inverted. Furthermore, all species showed reversal of strand asymmetry, suggesting that inversion of the A+T-rich region might be a synapomorphy of the Braconidae. Gene rearrangement events occurred in all braconid species, but gene rearrangement rates were not taxonomically correlated. Most rearranged genes were tRNAs, except those of Cotesia vestalis, in which 13 protein-coding genes and 14 tRNA genes changed positions or/and directions through three kinds of gene rearrangement events. Remote inversion is posited to be the result of two independent recombination events. Evolutionary rates were lower in species of the cyclostome group than those of noncyclostomes. Phylogenetic analyses based on complete mitochondrial genomes and secondary structure of rrnS supported a sister-group relationship between Aphidiinae and cyclostomes. Many well accepted relationships within Hymenoptera, such as paraphyly of Symphyta and Evaniomorpha, a sister-group relationship between Orussoidea and Apocrita, and monophyly of Proctotrupomorpha, Ichneumonoidea and Aculeata were robustly confirmed. New hypotheses, such as a sister-group relationship between Evanioidea and Aculeata, were generated. Among holometabolous insects, Hymenoptera was shown to be the sister to all other orders

Seasonal phenology of interactions involving short-lived annual plants, a multivoltine herbivore and its endoparasitoid wasp.

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Fei, Minghui; Gols, Rieta; Harvey, Jeffrey A

2014-01-01

Spatial-temporal realism is often missing in many studies of multitrophic interactions, which are conducted at a single time frame and/or involving interactions between insects with a single species of plant. In this scenario, an underlying assumption is that the host-plant species is ubiquitous throughout the season and that the insects always interact with it. We studied interactions involving three naturally occurring wild species of cruciferous plants, Brassica rapa, Sinapis arvensis and Brassica nigra, that exhibit different seasonal phenologies, and a multivoltine herbivore, the large cabbage white butterfly, Pieris brassicae, and its gregarious endoparasitoid wasp, Cotesia glomerata. The three plants have very short life cycles. In central Europe, B. rapa grows in early spring, S. arvensis in late spring and early summer, and B. nigra in mid to late summer. P. brassicae generally has three generations per year, and C. glomerata at least two. This means that different generations of the insects must find and exploit different plant species that may differ in quality and which may be found some distance from one another. Insects were either reared on each of the three plant species for three successive generations or shifted between generations from B. rapa to S. arvensis to B. nigra. Development time from neonate to pupation and pupal fresh mass were determined in P. brassicae and egg-to-adult development time and body mass in C. glomerata. Overall, herbivores performed marginally better on S. arvensis and B. nigra plants than on B. rapa plants. Parasitoids performance was closely tailored with that of the host. Irrespective as to whether the insects were shifted to a new plant in successive generations or not, development time of P. brassicae and C. glomerata decreased dramatically over time. Our results show that there were some differences in insect development on different plant species and when transferred from one species to another. However, all three

An Indirect Defence Trait Mediated through Egg-Induced Maize Volatiles from Neighbouring Plants.

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Daniel M Mutyambai

Full Text Available Attack of plants by herbivorous arthropods may result in considerable changes to the plant's chemical phenotype with respect to emission of herbivore-induced plant volatiles (HIPVs. These HIPVs have been shown to act as repellents to the attacking insects as well as attractants for the insects antagonistic to these herbivores. Plants can also respond to HIPV signals from other plants that warn them of impending attack. Recent investigations have shown that certain maize varieties are able to emit volatiles following stemborer egg deposition. These volatiles attract the herbivore's parasitoids and directly deter further oviposition. However, it was not known whether these oviposition-induced maize (Zea mays, L. volatiles can mediate chemical phenotypic changes in neighbouring unattacked maize plants. Therefore, this study sought to investigate the effect of oviposition-induced maize volatiles on intact neighbouring maize plants in 'Nyamula', a landrace known to respond to oviposition, and a standard commercial hybrid, HB515, that did not. Headspace volatile samples were collected from maize plants exposed to Chilo partellus (Swinhoe (Lepidoptera: Crambidae egg deposition and unoviposited neighbouring plants as well as from control plants kept away from the volatile emitting ones. Behavioural bioassays were carried out in a four-arm olfactometer using egg (Trichogramma bournieri Pintureau & Babault (Hymenoptera: Trichogrammatidae and larval (Cotesia sesamiae Cameron (Hymenoptera: Braconidae parasitoids. Coupled Gas Chromatography-Mass Spectrometry (GC-MS was used for volatile analysis. For the 'Nyamula' landrace, GC-MS analysis revealed HIPV production not only in the oviposited plants but also in neighbouring plants not exposed to insect eggs. Higher amounts of EAG-active biogenic volatiles such as (E-4,8-dimethyl-1,3,7-nonatriene were emitted from these plants compared to control plants. Subsequent behavioural assays with female T. bournieri and

Climate change and genetically modified insecticidal plants. Plant-herbivore interactions and secondary chemistry of Bt Cry1Ac-toxin producing oilseed rape (Brassica napus L.) under elevated CO{sub 2} or O{sub 3}

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Himanen, S.

2008-07-01

} and temperature despite differences in carbon and nitrogen concentrations between the non-Bt and Bt line. Feeding of Bt-susceptible diamondback moth (Plutella xylostella) larvae was equally inhibited on the Bt line in control conditions, under elevated CO{sub 2} and under O{sub 3} exposure. Constitutive glucosinolate and volatile terpenoid profiles of the non-Bt and Bt line plants were equal. Despite reduced feeding by Bt-susceptible P. xylostella on the Bt line, herbivore-induced increases in volatile terpenoids and glucosinolates were mostly comparable to those on the non-Bt line, with the exception of lowered increases in foliar concentration of 4-methoxy-3- indolylmethylglucosinolate and emissions of (E)-4,8-dimethyl-1,3,7-nonatriene, (E,E)-alpha-farnesene and alpha- thujene in the Bt-transgenic line. The effectiveness of the transgenic trait, measured as Bt toxin concentration of leaves, was maintained under elevated CO{sub 2} and temperature, separately and in combination, and enhanced under elevated O{sub 3}. As an effect of elevated CO{sub 2}, increased glucosinolate and volatile terpenoid concentrations were detected in both non-Bt and Bt plant lines, whereas O{sub 3} exposure changed concentrations of specific glucosinolates and decreased total terpenoid emissions in both plant types. In tritrophic bioassays, an endoparasitoid of P. xylostella, Cotesia vestalis, was attracted to host-damaged non-Bt and Bt plants under elevated CO{sub 2} compared to control plants, whereas with elevated O{sub 3} the host-damaged Bt plants, which had reduced feeding damage, did not attract the parasitoids. This is in contrast to non-Bt plants, which also remained attractive under O{sub 3} exposure. To conclude, Bt-producing oilseed rape showed equal responses as the non-Bt parent line to the studied abiotic variations in terms of vegetative growth, allocation to constitutive glucosinolates and volatile terpenoids and nontarget herbivore susceptibility. This suggests that these