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Sample records for armyworm spodoptera exigua

  1. Biochemical mechanisms for metaflumizone resistance in beet armyworm, Spodoptera exigua.

    Science.gov (United States)

    Tian, Xiangrui; Sun, Xingxing; Su, Jianya

    2014-07-01

    The metaflumizone, which belongs to the class of voltage-dependent sodium channel blockers, was registered to control Spodoptera exigua on vegetables in China in 2009. The present study revealed S. exigua has developed high resistance to this novel chemistry insecticide shortly after 2-3 years application in Guangdong Province of China. The metabolic mechanisms for metaflumizone resistance in this insect were analysed. The inhibitor of esterases greatly potentiates the toxicity of this chemical against the field resistant populations. The synergism ratio is 5.7 and 3.4-fold for S. exigua collected from Huizhou, Guangdong Province in 2011 and 2012, respectively. The activity of esterases in field populations (HZ12) is also significantly greater than that in the susceptible strain, and further significantly increased by challenge with metaflumizone for 3 generations. However, the inhibitor of P450s or GSTs only has slight synergism on metaflumizone toxicity against resistant populations, and there are no obvious differences in activities of P450s or GSTs between resistant populations and the susceptible strain. These results suggest that esterases might take pivotal role in conferring metabolic resistance to metaflumizone in the field populations of S. exigua, and P450s or GSTs are not involved in this resistance. Moreover, flavin-dependent monooxygenases (FMOs) are discovered to involve in metaflumizone resistance in the field populations of S. exigua. The FMO inhibitor, methimazole, potentiates metaflumizone toxicity in resistant larva of this species substantially. The synergism ratios for methimazole in resistant populations HZ11 and HZ12 were 3.1 and 1.9, respectively. Enzymatic assays also revealed higher FMO activities in resistant populations than in the susceptible strain, and successive selection with metaflumizone further increased the FMO activity in the field resistant population, but not significantly. The higher FMO activities in the older larval

  2. Projecting overwintering regions of the beet armyworm, Spodoptera exigua in China using the CLIMEX model.

    Science.gov (United States)

    Zheng, Xia-Lin; Wang, Pan; Cheng, Wen-Jie; Wang, Xiao-Ping; Lei, Chao-Liang

    2012-01-01

    The beet armyworm, Spodoptera exigua Hübner (Lepidoptera: Noctuidae) is a serious agricultural pest worldwide. However, population sources of S. exigua in outbreak regions are still vague due to the lack of understanding the distribution of overwintering regions, especially in China. In the present study, the potential overwintering regions of S. exigua in China are projected using the method of Compare Location in the CLIMEX model in order to understand the population sources in outbreak regions and establish an accurate forecasting system. The results showed the southern and northern overwintering boundaries near the Tropic of Cancer (about 23.5 (°)N) and the Yangtze River valley (about 30 (°)N), respectively. Meanwhile, the projection was supported by the data of fieldwork in 14 countries/cities during winter from 2008-2010. In conclusion, results of this study indicated that the overwintering regions of S. exigua were accurately projected by the CLIMEX model.

  3. Process-based modeling of the control of beet armyworm, Spodoptera exigua, with baculoviruses in greenhouse chrysanthemum

    NARCIS (Netherlands)

    Bianchi, F.J.J.A.

    2001-01-01

    This thesis describes the development of a process-based simulation model for the population dynamics of beet armyworm, Spodoptera exigua , and baculoviruses in greenhouse chrysanthemum. The model (BACSIM) has been validated for two baculoviruses with clear differences in biological characteristics,

  4. Various eicosanoids modulate the cellular and humoral immune responses of the beet armyworm, Spodoptera exigua.

    Science.gov (United States)

    Shrestha, Sony; Kim, Yonggyun

    2009-09-01

    Cyclooxygenase (COX) and lipoxygenase (LOX) can catalyze the oxidation of C20 fatty acids to produce certain eicosanoids, which play roles in mediating immune responses in insects. Despite their critical role in insect immunity, there have been few studies of the unique effects of different eicosanoids on immune responses. This study analyzed cellular and humoral immune responses of the beet armyworm, Spodoptera exigua, using seven eicosanoids selected from two major eicosanoid subgroups: prostaglandin (PG) and leukotriene (LT), derived from catalytic activities of COX and LOX respectively. Upon bacterial challenge, all seven eicosanoids (PGA(1), PGB(2), PGD(2), PGE(1), PGE(2), PGF(1alpha), and LTB(4)) significantly induced hemocyte nodulation and phagocytosis in the presence of dexamethasone, an eicosanoid biosynthesis inhibitor. However, only PGs induced cell lysis of oenocytoids to release prophenoloxidase, which resulted in an increase in phenoloxidase activity. These seven eicosanoids also induced expression of humoral immune-associated genes, including prophenoloxidase, serpin, dopa decarboxylase, cecropin, and lysozyme, in which PGB(2) and PGE(1) did not induce gene expression of prophenoloxidase. To understand the interactions between different eicosanoids, mixture effects of these eicosanoids were compared with their individual eicosanoid effects on mediating nodule formation in response to bacterial challenge. All six single PGs showed increases in nodule formation in a dose-dependent manner without significant difference among the different types. LTB(4) was more potent than the tested PGs in mediating the cellular immune response. At low doses, all combinations of two eicosanoids showed significant additive effects on nodule formation. These results indicate that immune target cells, such as hemocyte and fat body, of S. exigua can respond to different COX and LOX products to express cellular and humoral immune responses, and their overlapping, additive

  5. Does secondary plant metabolism provide a mechanism for plant defenses in the tropical soda apple Solanum viarum (Solanales: Solanaceae) against the beet armyworm Spodoptera exigua and southern armyworm S. eridania?

    Science.gov (United States)

    Survival assays were conducted with beet armyworm Spodoptera exigua and southern armyworm S. eridania with tropical soda apple Solanum viarum a relative of tomato. In addition, polyphenol oxidase (PPO) enzyme assays were conducted to determine if secondary plant defense compounds are being produce...

  6. The respiration rate of the beet armyworm pupae (Spodoptera exigua) after multi-generation intoxication with cadmium and zinc

    Energy Technology Data Exchange (ETDEWEB)

    Kramarz, Paulina; Kafel, Alina

    2003-11-01

    Zinc, but not cadmium, increased the respiration rate of pupae. - The beet armyworm (Spodoptera exigua) were fed on artificial food contaminated with zinc (200 mg kg{sup -1} dry mass) or cadmium (66 mg kg{sup -1} dry mass) for 15 generations. In 15th generation, O{sub 2} output and CO{sub 2} production of pupae were measured. Exposure to cadmium did not cause any effects whilst exposure to zinc led to a significant increase in the respiration rate of pupae. The average respiratory quotient (RQ) did not differ between treatments (ca. 0.7)

  7. Transcriptome Analysis and Screening for Potential Target Genes for RNAi-Mediated Pest Control of the Beet Armyworm, Spodoptera exigua.

    Science.gov (United States)

    Li, Hang; Jiang, Weihua; Zhang, Zan; Xing, Yanru; Li, Fei

    2013-01-01

    The beet armyworm, Spodoptera exigua (Hübner), is a serious pest worldwide that causes significant losses in crops. Unfortunately, genetic resources for the beet armyworm is extremely scarce. To improve these resources we sequenced the transcriptome of S. exigua representing all stages including eggs, 1(st) to 5(th) instar larvae, pupae, male and female adults using the Illumina Solexa platform. We assembled the transcriptome with Trinity that yielded 31,414 contigs. Of these contigs, 18,592 were annotated as protein coding genes by Blast searches against the NCBI nr database. It has been shown that knockdown of important insect genes by dsRNAs or siRNAs is a feasible mechanism to control insect pests. The first key step towards developing an efficient RNAi-mediated pest control technique is to find suitable target genes. To screen for effective target genes in the beet armyworm, we selected nine candidate genes. The sequences of these genes were amplified using the RACE strategy. Then, siRNAs were designed and chemically synthesized. We injected 2 µl siRNA (2 µg/µl) into the 4(th) instar larvae to knock down the respective target genes. The mRNA abundance of target genes decreased to different levels (∼20-94.3%) after injection of siRNAs. Knockdown of eight genes including chitinase7, PGCP, chitinase1, ATPase, tubulin1, arf2, tubulin2 and arf1 caused a significantly high level of mortality compared to the negative control (Ppest control.

  8. Effects of Tebufenozide on the Biological Characteristics of Beet Armyworm (Spodoptera exigua Hübner) and Its Resistance Selection

    Institute of Scientific and Technical Information of China (English)

    LIU Wei-wei; MU Wei; ZHU Bing-yu; LIU Feng

    2008-01-01

    In this article, the selection of tebufenozide to beet armyworm (Spodoptera exigua Hubner) was studied by the treatments to alternative generations' 3rd-instar larvae with LC50 dose and to continuous generations' larvae with LC10 dose; the effects of tebufenozide on the biological characteristics of current and subsequent generations were examined by the treatments to 3rd-instar larvae and egg pods in different concentrations. After treatments with LC50 dose till F11, the toxicity of tebufenozide to beet armyworm had no significant change, whereas the pupation rate, pupal weight, and fecundity were reduced markedly. After treatments with LC10 dose till F19, the beet armyworm only developed 3.52-fold resistance, and the main biological characteristics were nearly accordant in each generation. The livability was reduced 72 h later after treatments to 3rd-instar larvae, respectively in 2.5-40 (ig mL-', and larval duration, pupation rate, and pupal weight changed considerably with the increase in concentrations. The fecundity, larval livability, larval weight and pupal weight of subsequent generations were reduced as the dose increased over 10 ug mL-1. The hatching rate of egg pods did not differ with that of the controls obviously after treatment in 10-300 ug mL-1. But the larval livability, larval weight and pupal weight were reduced when eggs were exposed to 50 ug mL-1 dose or more. The results indicated that tebufenozide had low resistance risk to the current and subsequent generations of beet armyworm even if tebufenozide had significant effects on the biological characteristics of this insect.

  9. Molecular characterization and developmental expression of the gene encoding the prothoracicotropic hormone in the beet armyworm,Spodoptera exigua

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Prothoracicotropic hormone (PTTH), a neuropeptide hormone stimulating the prothoracic glands to synthesize ecdysone, plays an important role in regulating postembryonic development in insects. The cDNA encoding PTTH was isolated and sequenced from the beet armyworm, Spodoptera exigua (Spe). The deduced a?mino acid sequence is composed of a signal peptide, a peptide (65 amino acids) of un-known function, and a mature PTTH molecule (111 amino acids). The Spe-PTTH shows similarities (45.5%―70.3%) to other known PTTHs reported in Lepidoptera species, but 7 cysteine r?esidues and the hydrophobic regions were conserved. Whole-mount immunocytochemistry by using an antiserum against recombinant Helicoverpa armigera PTTH showed that Spe-PTTH was synthesized in two pairs of neurosecretory cells in the S. exigua brain. Northern blot analysis demonstrates the presence of a 1.2-kb transcript in the brain. The Spe-PTTH mRNA is detectable at high levels at the wandering larval stage, early pupal stage, and pharate adult stage, suggesting that the Spe-PTTH gene might be corre-lated with molting, metamorphosis, and reproduction.

  10. Molecular characterization and developmental expression of the gene encoding the prothoracicotropic hormone in the beet armyworm, Spodoptera exigua

    Institute of Scientific and Technical Information of China (English)

    XU Jun; SU JianYa; SHEN JinLiang; XU WeiHua

    2007-01-01

    Prothoracicotropic hormone (PTTH), a neuropeptide hormone stimulating the prothoracic glands to synthesize ecdysone, plays an important role in regulating postembryonic development in insects. The cDNA encoding PTTH was isolated and sequenced from the beet armyworm, Spodoptera exigua (Spe).The deduced amino acid sequence is composed of a signal peptide, a peptide (65 amino acids) of unknown function, and a mature PTTH molecule (111 amino acids). The Spe-PTTH shows similarities(45.5%-70.3%) to other known PTTHs reported in Lepidoptera species, but 7 cysteine residues and the hydrophobic regions were conserved. Whole-mount immunocytochemistry by using an antiserum against recombinant Helicoverpa armigera PTTH showed that Spe-PTTH was synthesized in two pairs of neurosecretory cells in the S. exigua brain. Northern blot analysis demonstrates the presence of a 1.2-kb transcript in the brain. The Spe-PTTH mRNA is detectable at high levels at the wandering larval stage, early pupal stage, and pharate adult stage, suggesting that the Spe-PTTH gene might be correlated with molting, metamorphosis, and reproduction.

  11. Transcriptome Analysis and Screening for Potential Target Genes for RNAi-Mediated Pest Control of the Beet Armyworm, Spodoptera exigua.

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    Hang Li

    Full Text Available The beet armyworm, Spodoptera exigua (Hübner, is a serious pest worldwide that causes significant losses in crops. Unfortunately, genetic resources for the beet armyworm is extremely scarce. To improve these resources we sequenced the transcriptome of S. exigua representing all stages including eggs, 1(st to 5(th instar larvae, pupae, male and female adults using the Illumina Solexa platform. We assembled the transcriptome with Trinity that yielded 31,414 contigs. Of these contigs, 18,592 were annotated as protein coding genes by Blast searches against the NCBI nr database. It has been shown that knockdown of important insect genes by dsRNAs or siRNAs is a feasible mechanism to control insect pests. The first key step towards developing an efficient RNAi-mediated pest control technique is to find suitable target genes. To screen for effective target genes in the beet armyworm, we selected nine candidate genes. The sequences of these genes were amplified using the RACE strategy. Then, siRNAs were designed and chemically synthesized. We injected 2 µl siRNA (2 µg/µl into the 4(th instar larvae to knock down the respective target genes. The mRNA abundance of target genes decreased to different levels (∼20-94.3% after injection of siRNAs. Knockdown of eight genes including chitinase7, PGCP, chitinase1, ATPase, tubulin1, arf2, tubulin2 and arf1 caused a significantly high level of mortality compared to the negative control (P<0.05. About 80% of the surviving insects in the siRNA-treated group of five genes (PGCP, chitinase1, tubulin1, tubulin2 and helicase showed retarded development. In chitinase1-siRNA and chitinase7-siRNA administered groups, 12.5% survivors exhibited "half-ecdysis". In arf1-siRNA and arf2-siRNA groups, the body color of 15% became black 48 h after injections. In summary, the transcriptome could be a valuable genetic resource for identification of genes in S. exigua and this study provided putative targets for RNAi pest

  12. Cadherin is involved in the action of Bacillus thuringiensis toxins Cry1Ac and Cry2Aa in the beet armyworm, Spodoptera exigua.

    Science.gov (United States)

    Qiu, Lin; Hou, Leilei; Zhang, Boyao; Liu, Lang; Li, Bo; Deng, Pan; Ma, Weihua; Wang, Xiaoping; Fabrick, Jeffrey A; Chen, Lizhen; Lei, Chaoliang

    2015-05-01

    Bacillus thuringiensis (Bt) insecticidal crystal (Cry) proteins are effective against some insect pests in sprays and transgenic crops, although the evolution of resistance could threaten the long-term efficacy of such Bt use. One strategy to delay resistance to Bt crops is to "pyramid" two or more Bt proteins that bind to distinct receptor proteins within the insect midgut. The most common Bt pyramid in cotton (Gossypium hirsutum L.) employs Cry1Ac with Cry2Ab to target several key lepidopteran pests, including the beet armyworm, Spodoptera exigua (Hübner), which is a serious migratory pest of many vegetable crops and is increasingly important in cotton in China. While cadherin and aminopeptidase-N are key receptors of Cry1 toxins in many lepidopterans including S. exigua, the receptor for Cry2A toxins remains poorly characterized. Here, we show that a heterologous expressed peptide corresponding to cadherin repeat 7 to the membrane proximal extracellular domain (CR7-MPED) in the S. exigua cadherin 1b (SeCad1b) binds Cry1Ac and Cry2Aa. Moreover, SeCad1b transcription was suppressed in S. exigua larvae by oral RNA interference and susceptibility to Cry1Ac and Cry2Aa was significantly reduced. These results indicate that SeCad1b plays important functional roles of both Cry1Ac and Cry2Aa, having major implications for resistance management for S. exigua in Bt crops.

  13. Comprehensive analysis of gene expression profiles of the beet armyworm Spodoptera exigua larvae challenged with Bacillus thuringiensis Vip3Aa toxin.

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    Yolanda Bel

    Full Text Available Host-pathogen interactions result in complex relationship, many aspects of which are not completely understood. Vip proteins, which are Bacillus thuringensis (Bt insecticidal toxins produced during the vegetative stage, are selectively effective against specific insect pests. This new group of Bt proteins represents an interesting alternative to the classical Bt Cry toxins because current data suggests that they do not share the same mode of action. We have designed and developed a genome-wide microarray for the beet armyworm Spodoptera exigua, a serious lepidopteran pest of many agricultural crops, and used it to better understand how lepidopteran larvae respond to the treatment with the insecticidal protein Vip3Aa. With this approach, the goal of our study was to evaluate the changes in gene expression levels caused by treatment with sublethal doses of Vip3Aa (causing 99% growth inhibition at 8 and 24 h after feeding. Results indicated that the toxin provoked a wide transcriptional response, with 19% of the microarray unigenes responding significantly to treatment. The number of up- and down-regulated unigenes was very similar. The number of genes whose expression was regulated at 8 h was similar to the number of genes whose expression was regulated after 24 h of treatment. The up-regulated sequences were enriched for genes involved in innate immune response and in pathogen response such as antimicrobial peptides (AMPs and repat genes. The down-regulated sequences were mainly unigenes with homology to genes involved in metabolism. Genes related to the mode of action of Bt Cry proteins were found, in general, to be slightly overexpressed. The present study is the first genome-wide analysis of the response of lepidopteran insects to Vip3Aa intoxication. An insight into the molecular mechanisms and components related to Vip intoxication will allow designing of more effective management strategies for pest control.

  14. Comprehensive analysis of gene expression profiles of the beet armyworm Spodoptera exigua larvae challenged with Bacillus thuringiensis Vip3Aa toxin.

    Science.gov (United States)

    Bel, Yolanda; Jakubowska, Agata K; Costa, Juliana; Herrero, Salvador; Escriche, Baltasar

    2013-01-01

    Host-pathogen interactions result in complex relationship, many aspects of which are not completely understood. Vip proteins, which are Bacillus thuringensis (Bt) insecticidal toxins produced during the vegetative stage, are selectively effective against specific insect pests. This new group of Bt proteins represents an interesting alternative to the classical Bt Cry toxins because current data suggests that they do not share the same mode of action. We have designed and developed a genome-wide microarray for the beet armyworm Spodoptera exigua, a serious lepidopteran pest of many agricultural crops, and used it to better understand how lepidopteran larvae respond to the treatment with the insecticidal protein Vip3Aa. With this approach, the goal of our study was to evaluate the changes in gene expression levels caused by treatment with sublethal doses of Vip3Aa (causing 99% growth inhibition) at 8 and 24 h after feeding. Results indicated that the toxin provoked a wide transcriptional response, with 19% of the microarray unigenes responding significantly to treatment. The number of up- and down-regulated unigenes was very similar. The number of genes whose expression was regulated at 8 h was similar to the number of genes whose expression was regulated after 24 h of treatment. The up-regulated sequences were enriched for genes involved in innate immune response and in pathogen response such as antimicrobial peptides (AMPs) and repat genes. The down-regulated sequences were mainly unigenes with homology to genes involved in metabolism. Genes related to the mode of action of Bt Cry proteins were found, in general, to be slightly overexpressed. The present study is the first genome-wide analysis of the response of lepidopteran insects to Vip3Aa intoxication. An insight into the molecular mechanisms and components related to Vip intoxication will allow designing of more effective management strategies for pest control.

  15. A novel Cry9Aa with increased toxicity for Spodoptera exigua (Hübner)

    NARCIS (Netherlands)

    Naimov, S.; Nedyalkova, R.; Staykov, N.; Weemen-Hendriks, M.; Minkov, I.; Maagd, de R.A.

    2014-01-01

    Cry9Aa, produced by Bacillus thuringiensis is reported to be not active against Spodoptera exigua (beet armyworm). In this study we have cloned a new cry9Aa5 gene encoding a protoxin with increased activity against S. exigua as compared to Cry9Aa1. When aligned to Cry9Aa1, four amino acid substituti

  16. Tropical soda apple (Solanum viarum) mediated competition via induced resistance: Interaction between Gratiana boliviana, Spodoptera exigua and Frankliniella occidentalis

    Science.gov (United States)

    Survival assays were conducted with beet armyworm (BAW) Spodoptera exigua (Hübner), a tortoise beetle Gratiana bolivana Spaeth and western flower thrips (WFT) Frankliniella occidentalis (Pergande) on tropical soda apple (TSA) Solanum viarum Dunal, a relative of tomato. Both S. exigua and G. bolivia...

  17. 甜菜夜蛾在四种寄主植物上的生命表参数比较研究%Comparative life table parameters of the beet armyworm,Spodoptera exigua, on four host plants

    Institute of Scientific and Technical Information of China (English)

    董钧锋; 张友军; 朱国仁; 王少丽

    2012-01-01

    在控制条件下对甜菜夜蛾Spodoptera exigua (Hübner)在白菜、大葱、甘蓝和豇豆上的生命表参数进行了比较研究.结果表明,甜菜夜蛾幼虫在4种寄主植物上均为5个龄期.幼虫和蛹在大葱上的发育历期最长,在白菜上最短.甘蓝叶片饲养的甜菜夜蛾生殖力最高,单雌产卵量为1 015.8粒,豇豆叶片上饲养的生殖力最低,为496.1粒.甜菜夜蛾在甘蓝上的内禀增长率和净增殖率最高,分别为0.237和287.82,在大葱上最低,分别为0.172和173.90.在大葱上甜菜夜蛾幼虫存活率较低,在其他3种寄主植物上较高.甜菜夜蛾的特定年龄生殖率在甘蓝叶片上最高,第22天单雌产卵量高达453.6粒.研究结果表明,在选取的4种植物中,甘蓝是甜菜夜蛾的最适寄主.%The effects of four host plants on life table parameters of beet armyworm, Spodoptera exigua (Hubner) , were studied in the laboratory at ( 27 ± 1 )℃ , relative humidity of 65% ±5% and photoperiod of 18L: 6D. The host plants tested were Chinese cabbage (Brassica campestris L. ssp. pekinensis (Lour. ) Olsson) , Chinese onion (Alliumfistulosum L. var. giganteum Makino) , cabbage (Brassica oleracea L. var. capitata L. ) , and bean ( Vigna unguiculata W. ssp. sesquipedalis ( L. ) Verd). The results show that five larval stages of 5, exigua occur on the four host plants tested. The larval and pupal periods were longest on Chinese onion, and shortest on Chinese cabbage. Among the different host plants, S. exigua exhibited the highest fecundity on cabbage, with 1 015.8 eggs/female and the lowest on bean, with 496. 1 eggs/female. The intrinsic rate of increase (rm) ranged from 0. 172 to 0. 237 , with the highest rate on cabbage and the lowest on Chinese onion. The highest net reproductive rate ( R0 ) was on cabbage, with 287.82 female/female/ generation and the lowest was on Chinese onion with 173. 90 female/female/generation. Larval survival was lower on Chinese onion than on the other

  18. Molecular genetics of the Spodoptera exigua multicapsid nucleopolyhedrovirus genome.

    NARCIS (Netherlands)

    Heldens, J.G.M.

    1998-01-01

    Spodoptera exigua multicapsid nucleopolyhedrovirus (SeMNPV) is an attractive biological control agent for the beet army worm S. exigua . This baculovirus has a narrow host range and is relatively, compared to other baculoviruses, virulent for beet army worm larvae. The molecular principles that spec

  19. 甜菜夜蛾雌蛾求偶行为及性信息素产生的时间节律%DIEL RHYTHMS OF CALLING BEHAVIOR AND SEX PHEROMONE PRODUCTION OF BEET ARMYWORM,SPODOPTERA EXIGUA ( LEPIDOPTERA: NOCTUIDAE)

    Institute of Scientific and Technical Information of China (English)

    董双林; 杜家纬

    2001-01-01

    研究了甜菜夜蛾雌蛾求偶行为和腺体中性信息素滴度时日变化的规律.结果表明,雌蛾求偶行为和性信息素滴度均呈明显的昼夜节律,且均在暗期的中后期达到高峰.比较而言,雌蛾的求偶活动期较短,在暗期中期开始,暗期结束后很快停止;但峰期较长,从中后期达到高峰后一直保持到暗期结束.而腺体内4种性信息素组份从暗期前0.5 h到下一个光期4.5 h均有产生;但峰期很短,暗期6.5 h显著增加达到高峰后,在8.5 h又迅速回落.日变化研究表明,甜菜夜蛾当日龄即可求偶,3日龄起进入求偶盛期,至7日龄末有明显减退.0~3日龄雌蛾的平均初始求偶时间逐日显著提前,以后则稳定在暗期5 h左右.不同日龄间性信息素滴度的变化较小.%Beet armyworm (BAW), Spodoptera exigua, is becoming one of more and more serious pests in China in recent years. As a part of research program of sex pheromone and its application of BAW in China,the hourly and daily variation of calling behavior and pheromone production of BAW females were investigated. Both calling behavior and titers of 4 sex pheromone components showed distinct diel rhythms, and the two peak periods were synchronous. In comparison, the calling activity lasted shorter period of time with a longer peak time, whereas the production of the sex pheromone lasted throughout the whole scotophase and part of the photophase with a very short peak time. The calling behavior began at the middle scotophase, reached the maximum at the middle-later scotophase, and continued the maximal calling activity until the end of the scotophase. When the light was on, the calling percentage reduced sharply, and all females stopped calling 1 hour later. The variation patterns of the 4 pheromone components in the glands of the 3 day old moths were similar from one to another. From 0.5 h before to 4.5 h into scotophase, the titers increased slightly, but at 6.5 h they showed a

  20. Virulence of Entomopathogenic Fungi Metarhizium anisopliae and Paecilomyces fumosoroseus for the Microbial Control of Spodoptera exigua.

    Science.gov (United States)

    Han, Ji Hee; Jin, Byung Rae; Kim, Jeong Jun; Lee, Sang Yeob

    2014-12-01

    The beet armyworm Spodoptera exigua (Lepidoptera: Noctuidae) is difficult to control using chemical insecticides because of the development of insecticide resistance. Several pest control agents are used to control the beet armyworm. Entomopathogenic fungi are one of the candidates for eco-friendly pest control instead of chemical control agents. In this study, among various entomopathogenic fungal strains isolated from soil two isolates were selected as high virulence pathogens against larva of beet armyworm. Control efficacy of fungal conidia was influenced by conidia concentration, temperature, and relative humidity (RH). The isolates Metarhizium anisopliae FT83 showed 100% cumulative mortality against second instar larvae of S. exigua 3 days after treatment at 1 × 10(7) conidia/mL and Paecilomyces fumosoroseus FG340 caused 100% mortality 6 days after treatment at 1 × 10(4) conidia/mL. Both M. anisopliae FT83 and P. fumosoroseus FG340 effectively controlled the moth at 20~30℃. M. anisopliae FT83 was significantly affected mortality by RH: mortality was 86.7% at 85% RH and 13.4% at 45% RH. P. fumosoroseus FG340 showed high mortality as 90% at 45% RH and 100% at 75% RH 6 days after conidia treatments. These results suggest that P. fumosoroseus FG340 and M. anisopliae FT83 have high potential to develop as a biocontrol agent against the beet armyworm.

  1. Roles of peroxinectin in PGE2-mediated cellular immunity in Spodoptera exigua.

    Directory of Open Access Journals (Sweden)

    Jiyeong Park

    Full Text Available Prostaglandins (PGs mediate insect immune responses to infections and invasions. Although the presence of PGs has been confirmed in several insect species, their biosynthesis in insects remains a conundrum because orthologs of the mammalian cyclooxygenases (COXs have not been found in the known insect genomes. PG-mediated immune reactions have been documented in the beet armyworm, Spodoptera exigua. The purpose of this research is to identify the source of PGs in S. exigua.Peroxidases (POXs are a sister group of COX genes. Ten putative POXs (SePOX-A ∼ SePOX-J were expressed in S. exigua. Expressions of SePOX-F and -H were induced by bacterial challenge and expressed in the hemocytes and the fat body. RNAi of each POX was performed by hemocoelic injection of their specific double-stranded RNAs. dsPOX-F or, separately, dsPOX-H, but not the other eight dsRNA constructs, specifically suppressed hemocyte-spreading behavior and nodule formation; these two reactions were also inhibited by aspirin, a COX inhibitor. PGE2, but not arachidonic acid, treatment rescued the immunosuppression. Sequence analysis indicated that both POX genes were clustered with peroxinectin (Pxt and their cognate proteins shared some conserved domains corresponding to the Pxt of Drosophila melanogaster.SePOX-F and -H are Pxt-like genes associated with PG biosynthesis in S. exigua.

  2. 寄主植物对甜菜夜蛾种群动态的影响%Effects of host plants on the population dynamics parameters of the beet armyworm, Spodoptera exigua

    Institute of Scientific and Technical Information of China (English)

    范锦胜; 张李香; 王贵强; 王慧姝

    2012-01-01

    为了明确甜菜夜蛾在藜、苋菜、甜菜和葱上的种群动态,通过室内试验,测定了4种寄主植物对甜菜夜蛾生长发育和繁殖等种群增长参数的影响,组建了甜菜夜蛾在供试植物上的实验种群生命表.结果表明,取食苋菜和藜的幼虫发育历期最短,而取食葱的发育历期最长(平均为16.00 d).蛹的发育历期在藜上最短(8.70 d),在苋菜上最长(10.30 d).寄主植物不影响甜菜夜蛾卵的孵化率和蛹的存活率,但影响幼虫的存活率.幼虫的存活率在藜上最高(74.67%),葱上最低(26.25%).藜、苋菜、甜菜和葱上甜菜夜蛾单雌平均产卵量分别为589.80、376.40、454.60、532.70粒.甜菜夜蛾雌蛾在藜、苋菜、甜菜、葱上的产卵呈现明显的动态变化.取食藜组和甜菜组雌蛾的产卵高峰出现在羽化后第2天,苋菜组为羽化后第3天,而葱组则为羽化后第1天和第3天.甜菜夜蛾在藜上的种群净增殖率(R0)、内禀增长率(γm)和周限增长率(λ)最高,平均世代周期(T)、种群加倍时间(t)最低.4种寄主植物中,甜菜夜蛾的适宜寄主植物依次为藜、苋菜、甜菜和葱.%The objective of this study was to understand the effects of four different host plants (Chenopodium album ,Amaranthus mangostanu,Beta vulgaris and Allium fistulosum) on the population dynamics of the beet armyworm. Individuals of a laboratory population of the beet armyworm were taken to observe the development, survival and reproduction on four host plants, and the life tables of beet armyworm was set up. The larval and pupal development periods were influenced by the host plants. The larvae feeding on the amaranth and lambsquartcr had shorter developmental duration, followed by those on the sugarbeet, whereas those on green onion had the longest developmental duration (16. 00 d). The pupal period was the shortest (8. 70 d) on the lambsquarter and longest on the amaranth (10. 30 d). The S. Exigua egg's hatching

  3. 甜菜夜蛾过氧化氢酶cDNA序列克隆、序列分析和表达特征%Cloning, sequence analysis and expression profiling of cDNA coding for catalase from the beet armyworm, Spodoptera exigua (Lepidoptera:Noctuidae )

    Institute of Scientific and Technical Information of China (English)

    胡振; 左洪亮; 李亚楠; 黄劲飞; 胡美英

    2011-01-01

    过氧化氧酶( catalase,CAT)作为生物体内的重要物质,其主要功能是参与活性氧代谢过程,在清除H2O2、超氧自由基和过氧化物以及阻止羟基自由基形成等方面发挥着重要作用.本研究利用RT-PCR技术和RACE方法首次克隆和分析了甜菜夜蛾Spodoptera exigua (Hübner) CAT基因,命名为SexiCAT,GenBank登录号为JN051294,其cNI)A序列全长为1 755 bp,开放阅渎框长1 524 bp,推测编码507个氨基酸.经氨基酸序列比对,此多肽序列具有高度保守性,与其他昆虫CAT的序列一致性分别为:家蚕Bombyx mori( 87%)、黑腹果蝇Drosophila melanogaster (73%)、埃及伊蚊Aedes aegypti (71%)和赤拟谷盗Tribolium castaneum (70%).对该基因在甜菜夜蛾各个发育时期以及不同组织表达量的荧光定量PCR分析表明,SexiCA7基因在甜菜夜蛾各个发育阶段的表达水平存在显著差异,其中成虫期的表达量最高,是卵期表达量的7倍,幼虫期次之,卵期最低;SexiCAT基因在5龄幼虫体壁、中肠、脂肪体和马氏管组织中都有表达,但在脂肪体中表达量最高.甜菜夜蛾SexiCAT基因的成功克隆及同源建模将为今后对其功能研究以及作为靶标没计新型氧化酶抑制剂提供了基础.%Catalase (CAT) , one of most important enzymes in organism, plays an essential role in active oxygen metabolism and preventing the formation of free hydroxyl radicals by clearing hydrogen peroxide, superoxide radical and peroxides. In this study, the full-length cDNA of CAT gene from the beet armyworm, Spodoptera exigua, was cloned and characterized by RT-PCR and RACE technique, which is 1 755 bp in length and named as SexiCAT ( GenBank accession no. JN051294). The open reading frame (ORF) of SexiCAT is 1 524 bp encoding 507 amino acid residues. The amino acid sequence of SexiCAT shares a significant identity with catelases of Bombyx mori (87% ), Drosophila melanogaster (73% ), Aedes aegypti (71%), and Tribolium

  4. PENGARUH EKSTRAK LIMBAH DAUN TEMBAKAU MADURA TERHADAP AKTIVITAS MAKAN LARVA Spodoptera exigua

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    Harwanto -

    2012-03-01

    Full Text Available Ekstrak tanaman untuk insektisida nabati tidak hanya berpengaruh terhadap mortalitas saja akan tetapi juga berpengaruh terhadap aktivitas makan serangga. Tujuan pengujian ini adalah untuk mengetahui pengaruh ekstraklimbah daun tembakau madura terhadap aktivitas makan larva instar III Spodoptera exigua. Metode uji ada dua yakni pakan pilihan dan pakan tanpa pilihan. Rancangan yang digunakan adalah rancangan acak lengkap (RAL, dengan 6 perlakuan konsentrasi dan 1 kontrol yang diulang 5 kali. Hasil pengujian menunjukkan bahwa pemaparan ekstrak limbah daun tembakau dengan metode pakan pilihan: (1 berpengaruh nyata terhadap bobot daun yang dikonsumsi pada semua konsentrasi dibandingkan dengan kontrol, (2 bersifat antifeedant terhadap larva S. exigua dengan indeks hambatan makan berkisar 17,51 – 38,12%, sedang ekstrak limbah daun tembakau pada uji pakan tanpa pilihan (3 berpengaruh nyata pada konsentrasi > 0,21% terhadap bobot daun yang dikonsumsi dibandingkan dengan kontrol, dan (4 bersifat antifeedant dengan indeks hambatan makan lebih tinggi (22,87 – 69,39% daripada dengan pakan pilihan (17,51 – 32,12%. Plants extracts used for botanical insecticides do not only influence the mortality but also the feeding activity of insects. The aim of this test was to determine the activity of the extract of Madura tobacco leaf on the feeding activity of the third instar of beet armyworm Spodoptera exigua. There were two test methods, choice and no-choice feeding tests. The design of each test was a completely randomized design (CRD, with six treatment concentrations and one control, replicated five times. The results showed that the exposure of tobacco leaf extracts with the choice feeding: (1 had significant effect on the leaf weight consumed at all concentration compared to the controls, (2 act as antifeedant against the larvae of S. exigua with the index of food consumption barrier ranging from 17.51 to 38.12%; while the extract of

  5. Bacillus thuringiensis Cry1Ca-resistant Spodoptera exigua lacks expression of one of four Aminopeptidase N genes

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    Moar William J

    2005-06-01

    Full Text Available Abstract Background Insecticidal toxins from Bacillus thuringiensis bind to receptors on midgut epithelial cells of susceptible insect larvae. Aminopeptidases N (APNs from several insect species have been shown to be putative receptors for these toxins. Here we report the cloning and expression analysis of four APN cDNAs from Spodoptera exigua. Results Suppression Subtractive Hybridization (SSH was used to construct cDNA libraries of genes that are up-and down-regulated in the midgut of last instar larvae of beet armyworm, S. exigua exposed to B. thuringiensis Cry1Ca toxin. Among the clones from the SSH libraries, cDNA fragments coding for two different APNs were obtained (APN2 and APN4. A similar procedure was employed to compare mRNA differences between susceptible and Cry1Ca resistant S. exigua. Among the clones from this last comparison, cDNA fragments belonging to a third APN (APN1 were detected. Using sequences obtained from the three APN cDNA fragments and degenerate primers for a fourth APN (APN3, the full length sequences of four S. exigua APN cDNAs were obtained. Northern blot analysis of expression of the four APNs showed complete absence of APN1 expression in the resistant insects, while the other three APNs showed similar expression levels in the resistant and susceptible insects. Conclusion We have cloned and characterized four different midgut APN cDNAs from S. exigua. Expression analysis revealed the lack of expression of one of these APNs in the larvae of a Cry1Ca-resistant colony. Combined with previous evidence that shows the importance of APN in the mode of action of B. thuringiensis toxins, these results suggest that the lack of APN1 expression plays a role in the resistance to Cry1Ca in this S. exigua colony.

  6. Lysozymes and lysozyme-like proteins from the fall armyworm, Spodoptera frugiperda.

    Science.gov (United States)

    Chapelle, Michael; Girard, Pierre-Alain; Cousserans, François; Volkoff, Nathalie-Anne; Duvic, Bernard

    2009-12-01

    Lysozyme is an important component of the insect non-specific immune response against bacteria that is characterized by its ability to break down bacterial cell-walls. By searching an EST database from the fall armyworm, Spodoptera frugiperda (Negre et al., 2006), we identified five sequences encoding proteins of the lysozyme family. The deduced protein sequences corresponded to three classical c-type lysozymes Sf-Lys1, Sf-Lys2 and Sf-Lys3, and two lysozyme-like proteins, Sf-LLP1 and Sf-LLP2. Sf-Lys1 was purified from the hemolymph of Escherichia coli-challenged S. frugiperda larvae. The mature protein had a molecular mass of 13.975 Da with an isoelectric point of 8.77 and showed 98.3% and 96.7% identity with lysozymes from Spodoptera litura and Spodoptera exigua, respectively. As the other insect lysozymes, Sf-Lys1 was active against gram positive bacteria such as Micrococcus luteus but also induced a slight permeabilization of the inner membrane of E. coli. Genes encoding these five Sf-Lys or Sf-LLPs were differentially up-regulated in three immune-competent tissues (hemocytes, fat body and gut) after challenges with non-pathogenic bacteria, E. coli and M. luteus, or entomopathogenic bacterium, Photorhabdus luminescens. Sf-Lys1 and Sf-Lys2 were mainly induced in fat body in the presence of E. coli or P. luminescens. Sf-Lys3, which had an acidic isoelectric point, was found to be the most up-regulated of all five Sf-Lys or Sf-LLPs in hemocytes and gut after challenge with P. luminescens. More molecular data are now available to investigate differences in physiological functions of these different members of the lysozyme superfamily.

  7. Characterization of DNA topoisomerase-1 in Spodoptera exigua for toxicity evaluation of camptothecin and hydoxy-camptothecin.

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    Lan Zhang

    Full Text Available Camptothecin (CPT, a plant alkaloid originally isolated from the native Chinese tree, Camptotheca acuminate, exerts the toxic effect by targeting eukaryotic DNA topoisomerase 1 (DNA Topo1. Besides as potent anti-cancer agents, CPT and its derivatives are now being explored as potential pesticides for insect control. In this study, we assessed their toxicity to an insect homolog, the Topo1 protein from beet armyworms (Spodoptera exigua Hübner, a worldwide pest of many important crops. The S. exigua Topo1 gene contains an ORF of 2790 base pairs that is predicted to encode a polypeptide of 930 amino acids. The deduced polypeptide exhibits polymorphism at residue sites V420, L530, A653 and T729 (numbered according to human Topo1 among insect species, which are predicted to confer sensitivity to CPT. The DNA relaxation activity of this protein was subsequently examined using a truncated form that contained the residues 337-930 and was expressed in bacteria BL21 cells. The purified protein retained the ability to relax double-stranded DNA and was susceptible to CPT and its derivative hydroxy-camptothecin (HCPT in a dose-dependent manner. The same inhibitory effect was also found on the native Topo1 extracted from IOZCAS-Spex-II cells, a cell line established from beet armyworms. Additionally, CPT and HCPT treatment reduced the steady accumulation of Topo1 protein despite the increased mRNA expression in response to the treatment. Our studies provide information of the S. exigua Topo1 gene and its amino acid polymorphism in insects and uncover some clues about potential mechanisms of CPT toxicity against insect pests. These results also are useful for development of more effective Topo1-targeted CPT insecticides in the future.

  8. Cloning and Expression of PAP cDNA in the Larvae of Beet armyworm, Spodoptera exigua ( Lepidoptera: Noctuidae)under High Temperature Stress%甜菜夜蛾PAP基因克隆及在高温胁迫下其表达量的变化

    Institute of Scientific and Technical Information of China (English)

    胡振; 龚亮; 张彦博; 胡美英

    2011-01-01

    Purple acid phosphatase (PAP) plays a critical role of organism under adversity stress. However, little work has been reported on PAP associated with adversity stress in insect. In this study, Sexi-PAP, a partial cDNA of the 3' end (GeneBank accession NO; HM566114) encoding purple acid phosphatase of beet armyworm, Spodoptera exigua(Hübner)was cloned, sequenced and analyzed. The cDNA is 759 bp that encodes 252 putative amino acids, which exhibited a significant similarity to purple acid phosphatase of Aedes aegypti(84% ) , Drosophila melanogaster (52% ) and Tribolium castaneum (50% ). Semi - quantitative RT-PCR was used to understand the effect of high temperature on the expression of PAP. The results indicated that high temperature could significantly induce the expression of PAP. The detailed results were that the PAP expression levels in the second instar larvae under 30 ℃ ,35 ℃ ,and 40 t for 10 h and 20 h, respectively, weresignificantly higher than those of the control groups( P <0.05 ). Furthermore, the expression of the treatment at 30℃ for 20 h had the highest relative gray value, and that at 25 ℃ for 20 h was the lowest. This study has suggested the possibility physiological role of the PAP at high temperature stress.%紫色酸性磷酸酯酶(purple acid phosphatase,PAP)在生物逆境胁迫中具有至关重要的作用,而在昆虫中此类基因极少见于报道.首次克隆和分析了甜菜夜蛾PAP基因cDNA 3’末端序列,在GenBank登录后,获得序列号为HM566114,其长为759个碱基对,推测编码252个氨基酸.此多肽序列具有高度保守性,其相似性分别为:埃及伊蚊(Aedes aegypti 84%;黑腹果蝇(Drosophila melanogaster)52%,赤拟谷盗(Tribolium castaneum)50%.为了研究高温对甜菜夜蛾PAP基因表达量的影响,利用RT - PCR技术,检测30℃,35℃,40℃胁迫下甜菜夜蛾2龄幼虫体内PAP基因表达量的变化,其中设对照组为25℃.结果表明:高温对甜菜夜蛾2龄幼虫PAP基因表

  9. Susceptibility of Spodoptera exigua to 9 toxins from Bacillus thuringiensis.

    Science.gov (United States)

    Hernández-Martínez, Patricia; Ferré, Juan; Escriche, Baltasar

    2008-03-01

    Nine of the most common lepidopteran active Cry proteins from Bacillus thuringiensis have been tested for activity against Spodoptera exigua. Because of possible intraspecific variability, three laboratory strains (FRA, HOL, and MUR) have been used. Mortality assays were performed with the three strains. LC(50) values for the active toxins were determined to the FRA and the HOL strains, whereas susceptibility of the MUR strain was assessed using only two concentrations. The results showed that Cry1Ca, Cry1Da, and Cry1Fa were the most effective toxins with all strains. Cry1Ab was found effective for the HOL strain, but very little effective against FRA (6.5-fold) and MUR strains. Cry1Aa and Cry1Ac were marginally toxic to all strains, whereas the rest of the toxins tested (Cry1Ba, Cry2Aa, and Cry2Ab) were non toxic. Significant differences in susceptibility among strains were also found for Cry1Da, being the FRA strain 25-fold more susceptible than the HOL strain. Growth inhibition, as an additional susceptibility parameter, was determined in the FRA strain with the 9 toxins. The toxicity profile obtained differed from that observed in mortality assays. Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ca, Cry1Da, and Cry1Fa toxins produced a similar larval growth inhibition. Cry2Aa had a lower but clear effect on larval growth inhibition, whereas Cry1Ba and Cry2Ab did not have any effect.

  10. Juvenile hormone analog technology: effects on larval cannibalism and the production of Spodoptera exigua (Lepidoptera: Noctuidae) nucleopolyhedrovirus.

    Science.gov (United States)

    Elvira, Sonia; Williams, Trevor; Caballero, Primitivo

    2010-06-01

    The production of a multiple nucleopolyhedrovirus (SeMNPV) of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), has been markedly increased by using juvenile hormone analog (JHA) technology to generate a supernumerary sixth instar in the species. In the current study we compared the incidence of cannibalism in S. exigua fifth and sixth instars reared at low (two larvae per dish) and a high density (10 larvae per dish). The incidence of cannibalism was significantly higher in fifth instars compared with sixth instars and increased with rearing density on both instars. Infected larvae were more prone to become victims of cannibalism than healthy individuals in mixed groups comprising 50% healthy + 50% infected larvae in both instars reared at high density. Instar had a marked effect on occlusion body (OB) production because JHA-treated insects produced between 4.8- and 5.6-fold increase in OB production per dish compared with fifth instars at high and low densities, respectively. The insecticidal characteristics of OBs produced in JHA-treated insects, as indicated by LD50 values, were similar to those produced in untreated fourth or fifth instars. Because JHA technology did not increase the prevalence of cannibalism and had no adverse effect on the insecticidal properties of SeMNPV OBs, we conclude that the use of JHAs to generate a supernumerary instar is likely to be compatible with mass production systems that involve gregarious rearing of infected insects.

  11. REPAT, a new family of proteins induced by bacterial toxins and baculovirus infection in Spodoptera exigua

    NARCIS (Netherlands)

    Herrero, S.; Ansems, M.; Oers, van M.M.; Vlak, J.M.; Bakker, P.L.; Maagd, de R.A.

    2007-01-01

    Insect larvae spend most of their time eating and the digestive tract is the most crucial barrier for the entrance of many pathogens. In our study, suppression subtractive hybridization (SSH) was used to compare Spodoptera exigua midgut gene expression between larvae exposed to the Bacillus thuringi

  12. REPAT, a new family of proteins induced by bacterial toxins and baculovirus infection in Spodoptera exigua.

    NARCIS (Netherlands)

    Herrero, S.; Ansems, M.; Oers, M.M. van; Vlak, J.M.; Bakker, P.L.; Maagd, R.A. de

    2007-01-01

    Insect larvae spend most of their time eating and the digestive tract is the most crucial barrier for the entrance of many pathogens. In our study, suppression subtractive hybridization (SSH) was used to compare Spodoptera exigua midgut gene expression between larvae exposed to the Bacillus thuringi

  13. Proteomic analysis of Cry2Aa-binding proteins and their receptor function in Spodoptera exigua

    Science.gov (United States)

    Qiu, Lin; Zhang, Boyao; Liu, Lang; Ma, Weihua; Wang, Xiaoping; Lei, Chaoliang; Chen, Lizhen

    2017-01-01

    The bacterium Bacillus thuringiensis produces Crystal (Cry) proteins that are toxic to a diverse range of insects. Transgenic crops that produce Bt Cry proteins are grown worldwide because of their improved resistance to insect pests. Although Bt “pyramid” cotton that produces both Cry1A and Cry2A is predicted to be more resistant to several lepidopteran pests, including Spodoptera exigua, than plants that produce Cry1Ac alone, the mechanisms responsible for the toxicity of Cry2Aa in S. exigua are not well understood. We identified several proteins that bind Cry2Aa (polycalin, V-ATPase subunits A and B, actin, 4-hydroxybutyrate CoA-transferase [4-HB-CoAT]), and a receptor for activated protein kinase C (Rack), in S. exigua. Recombinant, expressed versions of these proteins were able to bind the Cry2Aa toxin in vitro assays. RNA interference gene knockdown of the Se-V-ATPase subunit B significantly decreased the susceptibility of S. exigua larvae to Cry2Aa, whereas knockdown of the other putative binding proteins did not. Moreover, an in vitro homologous competition assay demonstrated that the Se-V-ATPase subunit B binds specifically to the Cry2Aa toxin, suggesting that this protein acts as a functional receptor of Cry2Aa in S. exigua. This the first Cry2Aa toxin receptor identified in S. exigua brush-border membrane vesicles. PMID:28067269

  14. Modeling climate change impacts on overwintering of Spodoptera exigua Hübner in regions of China

    Directory of Open Access Journals (Sweden)

    Xia-Lin Zheng

    2015-09-01

    Full Text Available Inferential models are usually used to evaluate the effect of winter warming on range expansion of insects. Generally, correlative approaches used to predict changes in the distributions of organisms are based on the assumption that climatic boundaries are fixed. Spodoptera exigua Htibner (Lepidoptera: Noctuidae overwinters as larvae or pupae in China regions. To understand the climate change impacts on overwintering of this species in regions of China, CLIMEX and Arc-GIS models were used to predict possible changes of distribution based on temperature. The climate change projection clearly indicated that the northern boundary of overwintering for S. exigua will shift northward from current distribution. Thus, the ongoing winter warming is likely to increase the frequency of S. exigua outbreaks.

  15. Baculovirus-Induced Climbing Behavior Favors Intraspecific Necrophagy and Efficient Disease Transmission in Spodoptera exigua.

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    Dulce Rebolledo

    Full Text Available Shortly prior to death, many species of Lepidoptera infected with nucleopolyhedrovirus climb upwards on the host plant. This results in improved dissemination of viral occlusion bodies over plant foliage and an increased probability of transmission to healthy conspecific larvae. Following applications of Spodoptera exigua multiple nucleopolyhedrovirus for control of Spodoptera exigua on greenhouse-grown sweet pepper crops, necrophagy was observed by healthy S. exigua larvae that fed on virus-killed conspecifics. We examined whether this risky behavior was induced by olfactory or phagostimulant compounds associated with infected cadavers. Laboratory choice tests and olfactometer studies, involving infected and non-infected cadavers placed on spinach leaf discs, revealed no evidence for greater attraction of healthy larvae to virus-killed over non-infected cadavers. Physical contact or feeding on infected cadavers resulted in a very high incidence of transmission (82-93% lethal disease. Observations on the behavior of S. exigua larvae on pepper plants revealed that infected insects died on the uppermost 10% of foliage and closer to the plant stem than healthy conspecifics of the same stage, which we considered clear evidence of baculovirus-induced climbing behavior. Healthy larvae that subsequently foraged on the plant were more frequently observed closer to the infected than the non-infected cadaver. Healthy larvae also encountered and fed on infected cadavers significantly more frequently and more rapidly than larvae that fed on non-infected cadavers. Intraspecific necrophagy on infected cadavers invariably resulted in virus transmission and death of the necrophagous insect. We conclude that, in addition to improving the dissemination of virus particles over plant foliage, baculovirus-induced climbing behavior increases the incidence of intraspecific necrophagy in S. exigua, which is the most efficient mechanism of transmission of this lethal

  16. Baculovirus-Induced Climbing Behavior Favors Intraspecific Necrophagy and Efficient Disease Transmission in Spodoptera exigua.

    Science.gov (United States)

    Rebolledo, Dulce; Lasa, Rodrigo; Guevara, Roger; Murillo, Rosa; Williams, Trevor

    2015-01-01

    Shortly prior to death, many species of Lepidoptera infected with nucleopolyhedrovirus climb upwards on the host plant. This results in improved dissemination of viral occlusion bodies over plant foliage and an increased probability of transmission to healthy conspecific larvae. Following applications of Spodoptera exigua multiple nucleopolyhedrovirus for control of Spodoptera exigua on greenhouse-grown sweet pepper crops, necrophagy was observed by healthy S. exigua larvae that fed on virus-killed conspecifics. We examined whether this risky behavior was induced by olfactory or phagostimulant compounds associated with infected cadavers. Laboratory choice tests and olfactometer studies, involving infected and non-infected cadavers placed on spinach leaf discs, revealed no evidence for greater attraction of healthy larvae to virus-killed over non-infected cadavers. Physical contact or feeding on infected cadavers resulted in a very high incidence of transmission (82-93% lethal disease). Observations on the behavior of S. exigua larvae on pepper plants revealed that infected insects died on the uppermost 10% of foliage and closer to the plant stem than healthy conspecifics of the same stage, which we considered clear evidence of baculovirus-induced climbing behavior. Healthy larvae that subsequently foraged on the plant were more frequently observed closer to the infected than the non-infected cadaver. Healthy larvae also encountered and fed on infected cadavers significantly more frequently and more rapidly than larvae that fed on non-infected cadavers. Intraspecific necrophagy on infected cadavers invariably resulted in virus transmission and death of the necrophagous insect. We conclude that, in addition to improving the dissemination of virus particles over plant foliage, baculovirus-induced climbing behavior increases the incidence of intraspecific necrophagy in S. exigua, which is the most efficient mechanism of transmission of this lethal pathogen.

  17. Down-regulation of a chitin synthase a gene by RNA interference enhances pathogenicity of Beauveria bassiana ANU1 against Spodoptera exigua (HÜBNER).

    Science.gov (United States)

    Lee, Jung-Bok; Kim, Hyun Soo; Park, Youngjin

    2017-02-01

    Chitin synthase (CHS) is an important enzymatic component, which is required for chitin formation in the cuticles and cuticular linings of other tissues in insects. CHSs have been divided into two classes, classes A and B, based on their amino acid sequence similarities and functions. Class A CHS (CHS-A) is specifically expressed in the epidermis and related ectodermal cells such as tracheal cells, while class B CHS (CHS-B) is expressed in gut epithelial cells that produce peritrophic matrices. In this study, we cloned the CHS-A gene from the beet armyworm, Spodoptera exigua (SeCHS-A). The SeCHS-A contains an open reading frame of 4,698 nucleotides, encoding a protein of 1,565 amino acids with a predicted molecular mass of approximately 177.8 kDa. The SeCHS-A mRNA was expressed in all developmental stages and specifically in the epidermis and tracheae tissue by quantitative real-time-PCR analysis. Expression of SeCHS-A gene was suppressed by feeding double-stranded RNA (dsCHS-A, 400 ng/larva) in the third instar larvae of S. exigua. Suppression of the SeCHS-A gene expression significantly increased 35% of mortality on pupation of S. exigua. Also, the third instar larvae fed with dsCHS-A significantly increased susceptibility to entomopathogenic fungi, Beauveria bassiana ANU1 at 3 days after treatment. These results suggest that the SeCHS-A gene plays an important role in development of S. exigua and RNA interference may apply to effective pest control with B. bassiana.

  18. Three metabolites from an entomopathogenic bacterium, Xenorhabdus nematophila, inhibit larval development of Spodoptera exigua (Lepidoptera: Noctuidae) by inhibiting a digestive enzyme, phospholipase A2

    Institute of Scientific and Technical Information of China (English)

    Jaehyun Kim; Yonggyun Kim

    2011-01-01

    An entomopathogenic bacterium, Xenorhabdus nematophila, has been known to induce significant immunosuppression of target insects by inhibiting immune-associated phospholipase A2 (PLA2), which subsequently shuts down biosynthesis of eicosanoids that are critical in immune mediation in insects. Some metabolites originated from the bacterial culture broth have been identified and include benzylideneacetone, proline-tyrosine and acetylated phenylalanine-glycine-valine, which are known to inhibit enzyme activity of PLA2 extracted from hemocyte and fat body. This study tested their effects on digestive PLA2 of the beet armyworm, Spodoptera exigua. Young larvae fed different concentrations of the three metabolites resulted in significant adverse effects on larval development even at doses below 100 μg/mL. In particular, they induced significant reduction in digestive efficiency of ingested food. All three metabolites significantly inhibited catalytic activity of digestive PLA2 extracted from midgut lumen of the fifth instar larvae at a low micromolar range. These results suggest that the inhibitory activities of the three bacterial metabolites on digestive PLA2 of S. exigua midgut may explain some of their oral toxic effects.

  19. 甜菜夜蛾触角结合蛋白Ⅱ的cDNA克隆、组织分布及配体结合特性分析%cDNA cloning, tissue distribution and ligand binding characteristics of antennal binding protein 2 from the beet armyworm, Spodoptera exigua ( Lepidoptera: Noctuidae )

    Institute of Scientific and Technical Information of China (English)

    张婷; 刘乃勇; 董双林

    2012-01-01

    Antennal binding proteins (ABPs) represent a sub-class of odorant binding proteins (OBPs), and thus are assumed to play a role in insect olfaction. In order to explore the role of ABPs in olfaction, the full-length cDNA of an antennal binding protein 2 gene from Spodoptera exigua ( SexigABPl ) (GenBank accession no. HQ234486) was identified by transcriptome analysis and RACE technology. The sequence analysis showed that SexigABPl contains a 444 bp open reading frame that encodes 148 amino acids including the six conserved cysteine residues of typical OBPs. SexigABP2 shares the highest amino acid identity (up to 72% ) with an ABP2 from Heliothis virescens ( HvirABP2). The results of realtime quantitative PCR showed that SexigABPl was highly expressed in male and female antennae, but weakly expressed in proboscis, legs, and wings of both sexes. The expression levels in female antennae and legs were significantly higher than those in male antennae and legs, respectively. SexigABPl was further expressed in a prokaryotic expression system, and the protein was purified. By fluorescence competitive binding assay, the affinities of SexigABP2 with 35 odorant compounds were tested. Among the tested ligands, (Z)-9-tetradecenol (a sex pheromone component of S. exigua) and farnesol (a plant volatile compound) showed the highest affinity, with the Ki values of 8. 24 μmol/L and 8. 14 μmol/L, respectively. Affinity comparison indicated that long carbon-chain compounds with unsaturated bond(s) exhibited the higher affinities than short ones without unsaturated bond; among the unsaturated long carbon-chain compounds, however, alcohols displayed higher affinities than acetates. The results suggest that SexigABPZ might be involved in perception of plant volatile compounds with a long carbon-chain and unsaturated bonds.%触角结合蛋白(antennal binding proteins,ABPs)是气味结合蛋白(odorant binding proteins,oBPs)的一个亚类,推测其在昆虫嗅觉中起作用.为了探

  20. Susceptibility of Spodoptera frugiperda and S. exigua to Bacillus thuringiensis Vip3Aa insecticidal protein.

    Science.gov (United States)

    Chakroun, Maissa; Bel, Yolanda; Caccia, Silvia; Abdelkefi-Mesrati, Lobna; Escriche, Baltasar; Ferré, Juan

    2012-07-01

    The Vip3Aa protein is an insecticidal protein secreted by Bacillus thuringiensis during the vegetative stage of growth. The activity of this protein has been tested after different steps/protocols of purification using Spodoptera frugiperda as a control insect. The results showed that the Vip3Aa protoxin was stable and retained full toxicity after being subjected to common biochemical steps used in protein purification. Bioassays with the protoxin in S. frugiperda and S. exigua showed pronounced differences in LC(50) values when mortality was measured at 7 vs. 10d. At 7d most live larvae were arrested in their development. LC(50) values of "functional mortality" (dead larvae plus larvae remaining in the first instar), measured at 7d, were similar or even lower than the LC(50) values of mortality at 10d. This strong growth inhibition was not observed when testing the trypsin-activated protein (62 kDa) in either species. S. exigua was less susceptible than S. frugiperda to the protoxin form, with LC(50) values around 10-fold higher. However, both species were equally susceptible to the trypsin-activated form. Processing of Vip3Aa protoxin to the activated form was faster with S. frugiperda midgut juice than with S. exigua midgut juice. The results strongly suggest that the differences in the rate of activation of the Vip3Aa protoxin between both species are the basis for the differences in susceptibility towards the protoxin form.

  1. [Realized resistance heritability and resistance risk of spodoptera exigua to cyhalothrin, fenvalerate and alpha-cypermethrin].

    Science.gov (United States)

    Lan, Yiquan; Zhao, Shixi; Wu, Gang

    2006-03-01

    In this paper, Spodoptera exigua from Fuzhou of Fujian Province was continuously selected and bred to test its resistance to cyhalothrin, fenvalerate and alpha-cypermethrin, and to evaluate its realized resistance heritability (h2) and resistance risk. The results showed that after 12, 10, and 10 generations, the resistance of S. exigua to cyhalothrin, fenvalerate and alpha-cypermethrin was increased by 18.1-, 27.6-, and 45.4-fold, and the realized cyhalothrin, fenvalerate and alpha-cypermethrin was increased by 18.1-, 27.6-, and 45.4-fold, and the realized resistance heritability was 0. 2567, 0. 3571 and 0. 4239, respectively. Assuming that the h2 of field S. exigua population was half of these values, it required 9 to approximately 20 generations for cyhalothrin, 6 to approximately 14 generations for fenvalerate, and 5 to approximately12 generations for alpha-cypermethrin to obtain 10-fold increase in resistance under selective pressure of 50% to approximately 90 % mortality for each selective generation. Of the three pyrethroids, the resistance risk to cyhalothrin was smaller than that to fenvalerate and alpha-cypermethrin.

  2. Synthesis of tritiated sex pheromones of the processionary moth Thaumetopoea pityocampa and the Egyptian armyworm Spodoptera littoralis

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero, Angel; Feixas, Joan [CID (CDIC), Biological Organic Chemistry Dept., Barcelona (Spain)

    1996-10-01

    Synthesis of tritiated sex phenomones of the processionary moth Thaumetopoea pityocampa and the Egyptian armyworm Spodoptera littoralis has been accomplished by a simple route involving tritiated sodium borohydride reduction of the corresponding aldehyde followed by acetylation of the resulting radiolabelled alcohol. The process occurs with high chemical and radiochemical yields and the compounds have been used in pheromone catabolism studies. (author).

  3. Manejo convencional de Spodoptera exigua en cultivos del municipio de Los Reyes de Juárez, Puebla

    OpenAIRE

    2013-01-01

    Spodoptera exigua es un insecto plaga de importancia agrícola mundial que afecta una gran variedad de cultivos, entre los que destacan ornamentales, granos básicos y hortalizas. El método de control más utilizado son los insecticidas químicos de síntesis; sin embargo, se han reportado cambios en la susceptibilidad del insecto a diversos insecticidas. Esta adaptación ha venido en aumento, existiendo reportes de un gran número de insecticidas para los cuales S. exigua ha desarrollado resistenci...

  4. Constitutive activation of the midgut response to Bacillus thuringiensis in Bt-resistant Spodoptera exigua.

    Directory of Open Access Journals (Sweden)

    Patricia Hernández-Martínez

    Full Text Available Bacillus thuringiensis is the most effective microbial control agent for controlling numerous species from different insect orders. The main threat for the long term use of B. thuringiensis in pest control is the ability of insects to develop resistance. Thus, the identification of insect genes involved in conferring resistance is of paramount importance. A colony of Spodoptera exigua (Lepidoptera: Noctuidae was selected for 15 years in the laboratory for resistance to Xentari™, a B. thuringiensis-based insecticide, reaching a final resistance level of greater than 1,000-fold. Around 600 midgut ESTs were analyzed by DNA-macroarray in order to find differences in midgut gene expression between susceptible and resistant insects. Among the differentially expressed genes, repat and arylphorin were identified and their increased expression was correlated with B. thuringiensis resistance. We also found overlap among genes that were constitutively over-expressed in resistant insects with genes that were up-regulated in susceptible insects after exposure to Xentari™, suggesting a permanent activation of the response to Xentari™ in resistant insects. Increased aminopeptidase activity in the lumen of resistant insects in the absence of exposure to Xentari™ corroborated the hypothesis of permanent activation of response genes. Increase in midgut proliferation has been proposed as a mechanism of response to pathogens in the adult from several insect species. Analysis of S. exigua larvae revealed that midgut proliferation was neither increased in resistant insects nor induced by exposure of susceptible larvae to Xentari™, suggesting that mechanisms other than midgut proliferation are involved in the response to B. thuringiensis by S. exigua larvae.

  5. Microsatellite markers for genetic studies of the fall armyworm, Spodoptera frugiperda.

    Science.gov (United States)

    Pavinato, V A C; Martinelli, S; de Lima, P F; Zucchi, M I; Omoto, C

    2013-02-08

    We developed six microsatellite markers for the fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae). The SSR loci were isolated with enriched genomic library protocol by using native individuals as a genome source for markers. These loci were characterized in 48 individuals and they were tested for the ability to identify candidate migrants exchanged among the samples. The number of alleles per locus ranged from 5 to 18 (10.8 on average). The observed polymorphism information content ranged from 0.172 to 0.891. Beside the lower efficiency to obtain SSR loci, the six microsatellites were polymorphic and sufficiently discriminant for the genetic studies of S. frugiperda; it allowed us to identify migrants with both NJ clustering and the Bayesian methods. These markers will be useful for molecular ecology studies of this highly polyphagous species in order to understand the processes that determine genetic differentiation in the complex agro-ecosystems that it infests and improve local integrated pest management practices.

  6. Herbivore cues from the fall armyworm (Spodoptera frugiperda) larvae trigger direct defenses in maize.

    Science.gov (United States)

    Chuang, Wen-Po; Ray, Swayamjit; Acevedo, Flor Edith; Peiffer, Michelle; Felton, Gary W; Luthe, Dawn S

    2014-05-01

    In addition to feeding damage, herbivores release cues that are recognized by plants to elicit defenses. Caterpillar oral secretions have been shown to trigger herbivore defense responses in several different plant species. In this study, the effects of two fall armyworm (Spodoptera frugiperda) oral secretions (saliva and regurgitant) on caterpillar defense responses in maize (Zea mays) were examined. Only minute amounts of regurgitant were deposited on the maize leaf during larval feeding bouts and its application to leaves failed to induce the expression of several herbivore defense genes. On the other hand, caterpillars consistently deposited saliva on leaves during feeding and the expression of several maize defense genes significantly increased in response to saliva application and larval feeding. However, feeding by ablated caterpillars with impaired salivation did not induce these defenses. Furthermore, bioassays indicated that feeding by unablated caterpillars significantly enhanced defenses when compared with that of ablated caterpillars. Another critical finding was that the maize genotype and stage of development affected the expression of defense genes in response to wounding and regurgitant treatments. These results demonstrate that fall armyworm saliva contains elicitors that trigger herbivore defenses in maize.

  7. Phylogenetic position and replication kinetics of Heliothis virescens ascovirus 3h (HvAV-3h isolated from Spodoptera exigua.

    Directory of Open Access Journals (Sweden)

    Guo-Hua Huang

    Full Text Available Insect-specific ascoviruses with a circular genome are distributed in the USA, France, Australia and Indonesia. Here, we report the first ascovirus isolation from Spodoptera exigua in Hunan, China. DNA-DNA hybridization to published ascoviruses demonstrated that the new China ascovirus isolate is a variant of Heliothis virescens ascovirus 3a (HvAV-3a, thus named HvAV-3h. We investigated the phylogenetic position, cell infection, vesicle production and viral DNA replication kinetics of HvAV-3h, as well as its host-ranges. The major capsid protein (MCP gene and the delta DNA polymerase (DNA po1 gene of HvAV-3h were sequenced and compared with the available ascovirus isolates for phylogenetic analysis. This shows a close relationship with HvAV-3g, originally isolated from Indonesia, HvAV-3e from Australia and HvAV-3c from United States. HvAV-3h infection induced vesicle production in the SeE1 cells derived from S. exigua and Sf9 cells derived from S. frugiperda, resulting in more vesicles generated in Sf9 than SeE1. Viral DNA replication kinetics of HvAV-3h also demonstrated a difference between the two cell lines tested. HvAV-3h could readily infect three important insect pests Helicoverpa armigera (Hübner, Spodoptera exigua (Hübner and Spodoptera litura (Fabricius from two genera in different subfamilies with high mortalities.

  8. Characterization and expression patterns of a membrane-bound trehalase from Spodoptera exigua

    Directory of Open Access Journals (Sweden)

    Xu Weihua

    2008-05-01

    Full Text Available Abstract Background The chitin biosynthesis pathway starts with trehalose in insects and the main functions of trehalases are hydrolysis of trehalose to glucose. Although insects possess two types, soluble trehalase (Tre-1 and membrane-bound trehalase (Tre-2, very little is known about Tre-2 and the difference in function between Tre-1 and Tre-2. Results To gain an insight into trehalase functions in insects, we investigated a putative membrane-bound trehalase from Spodoptera exigua (SeTre-2 cloned from the fat body. The deduced amino acid sequence of SeTre-2 contains 645 residues and has a predicted molecular weight of ~74 kDa and pI of 6.01. Alignment of SeTre-2 with other insect trehalases showed that it contains two trehalase signature motifs and a putative transmembrane domain, which is an important characteristic of Tre-2. Comparison of the genomic DNA and cDNA sequences demonstrated that SeTre-2 comprises 13 exons and 12 introns. Southern blot analysis revealed that S. exigua has two trehalase genes and that SeTre-2 is a single-copy gene. Northern blot analyses showed that the SeTre-2 transcript is expressed not only in the midgut, as previously reported for Bombyx mori, but also in the fat body and Malpighian tubules, although expression patterns differed between the midgut and fat body. SeTre-2 transcripts were detected in the midgut of feeding stage larvae, but not in pupae, whereas SeTre-2 mRNA was detected in the fat body of fifth instar larvae and pupae. Conclusion These findings provide new data on the tissue distribution, expression patterns and potential function of membrane-bound trehalase. The results suggest that the SeTre-2 gene may have different functions in the midgut and fat body.

  9. [Resistance mechanisms of Spodoptera exigua (Hübner) to fenvalerate and alpha-cypermethrin].

    Science.gov (United States)

    Lan, Yi-Quan; Zhao, Shi-Xi

    2010-01-01

    By using synergist bioassay and biochemical analysis, this paper approached the resistance mechanisms of Spodoptera exigua (Hübner) to fenvalerate and alpha-cypermethrin. The synergistic ratios of piperonyl butoxide (PBO), o, o-diethyl-o-phenyl-thiophosphate (SV1), triphenyl phosphate (TPP), and diethyl maleate (DEM) between fenvalerate-resistant strain (Fen-R) and susceptible strain were 10.2, 7.8, 12.5, and 1.1, and those between alpha-cypermethrin resistant strain (Cyp-R) and susceptible strain were 21.6, 15.5, 8.6, and 1.2, respectively. Significant synergisms of PBO, SV1, and TPP to fenvalerate and alpha-cypermethrin were observed, implying that multifunctional oxidase and carboxylesterase were involved in the resistance to fenvalerate and alpha-cypermethrin. The carboxylesterase activities in the fourth instar larvae of Cyp-R and Fen-R strains were 1.9 and 2.2 folds of the corresponding susceptible strains, respectively, but no differences were found in the glutathione-S-transferase activities between the resistant and susceptible strains, which indicated that carboxylesterase played an important role in the resistance of S. exigua to fenvalerate and alpha-cypermethrin, while glutathione-S-transferase contributed little to the resistance. There were no significant differences in the Na-K-ATPase activities between the resistant and susceptible strains, but the inhibition of fenvalerate and alpha-cypermethrin on Na-K-ATPase was higher in the susceptible strains than in the resistant strains, indicating the decreased sensitivity of Na-K-ATPase in resistant strains.

  10. Toxicity of pyrrolizidine alkaloids to Spodoptera exigua using insect cell lines and injection bioassays.

    Science.gov (United States)

    Nuringtyas, Tri R; Verpoorte, Robert; Klinkhamer, Peter G L; van Oers, Monique M; Leiss, Kirsten A

    2014-06-01

    Pyrrolizidine alkaloids (PAs) are feeding deterrents and toxic compounds to generalist herbivores. Among the PAs of Jacobaea vulgaris Gaertn, jacobine and erucifoline are the most effective against insect herbivores as indicated by correlative studies. Because little is known about the effect of jacobine and erucifoline as individual PAs, we isolated these compounds from their respective Jacobaea chemotypes. These PAs and other commercially available senecionine-like PAs, including senecionine, seneciphylline, retrorsine, and senkirkine, were tested as free base and N-oxide forms at a range of 0-70 ppm. Feeding bioassays using live insects are closer to the natural pattern but require relatively large amounts of test compounds. We, therefore, compared the toxicity of PAs using both Spodoptera exigua cell line and larval injection bioassays. Both bioassays led to similar results in the order of PA toxicity, indicating that the cell lines are a valuable tool for a first toxicity screen. Testing individual PAs, jacobine and erucifoline were the most toxic PAs, suggesting their major role in plant defense against generalist herbivores. Senkirkine and seneciphylline were less toxic than jacobine and erucifoline but more toxic than retrorsine. Senecionine was not toxic at the tested concentrations. For all toxic PAs, the free base form was more toxic than the N-oxide form. Our results demonstrate that structural variation of PAs influences their effectiveness in plant defense.

  11. Gene knockout demonstrates that vip3A contributes to the pathogenesis of Bacillus thuringiensis toward Agrotis ipsilon and Spodoptera exigua.

    Science.gov (United States)

    Donovan, W P; Donovan, J C; Engleman, J T

    2001-07-01

    Vip3A is an 89-kDa protein secreted by Bacillus thuringiensis during vegetative growth. To determine the importance of Vip3A for the insect pathogenicity of B. thuringiensis the vip3A gene was deleted from strain HD1, yielding strain HD1Deltavip3A. Compared with HD1, strain HD1Deltavip3A was one-fourth as toxic to Agrotis ipsilon larvae and less than one-tenth as toxic to Spodoptera exigua larvae. When streptomycin was included in the S. exigua diet the toxicity of HD1Deltavip3A was approximately half that of HD1. Addition of HD1 spores increased the toxicity of purified Cry1 protein more than 600-fold against S. exigua, whereas addition of HD1Deltavip3A spores increased toxicity of Cry1 protein approximately 10-fold. These results demonstrate that an important component of B. thuringiensis insecticidal activity against S. exigua is the synthesis of Vip3A protein by B. thuringiensis cells after ingestion of spores and crystal proteins by insect larvae.

  12. Effects of gamma radiation on larvae of Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) fall armyworm

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Valter; Arthur, Paula B.; Silva, Lucia C.A.S.; Franco, Jose G.; Harder, Marcia N.C., E-mail: arthur@cena.usp.br, E-mail: mnharder@terra.com.br [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil); Franco, Suely S.H.; Machi, Andre R., E-mail: gilmita@uol.com.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    One of the most harmful insects the corn culture is the Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae), known commonly as fall armyworm, it is would originate of the tropical and subtropical areas of the American continent; its economical importance is due polyphagism, attacking countless grassy, such as corn, sorghum, wheat, barley, rice and pastures. One of the methods more used in the moment is the chemical control that during several applications the insect can turn resistant, then news researches has been made to the control of the insects. Due what was exposed the objective of the research was evaluated the effects of gamma radiation on larvae of S. frugiperda. Insects were rear in artificial diet. Each treatment had 5 repetitions with 20 larvae with 15-20 days of age in the total of 100 larvae per treatment. The larvae were irradiated with doses of gamma radiation of: 0 (control), 50, 100, 200 and 300 Gy, in source of Cobalt-60, type Gammacell-220, at dose rate of 0,508 kGy/hour. After irradiation the insects were keep in room with climatic conditions of 25 ± 5 dec C and 70 ± 5% R.H. Were evaluated the emergence of adults. The results showed that the dose of 300 Gy was the lethal dose to larvae irradiated, and 200 Gy the sterilizing dose to adults. (author)

  13. Potential of trap crops for integrated management of the tropical armyworm, Spodoptera litura in tobacco.

    Science.gov (United States)

    Zhou, Zhongshi; Chen, Zepeng; Xu, Zaifu

    2010-01-01

    The tropical armyworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae), is an important pest of tobacco, Nicotiana tabacum L. (Solanales: Solanaceae), in South China that is becoming increasingly resistant to pesticides. Six potential trap crops were evaluated to control S. litura on tobacco. Castor bean, Ricinus communis L. (Malpighiales: Euphorbiaceae), and taro, Colocasia esculenta (L.) Schott (Alismatales: Araceae), hosted significantly more S. litura than peanut, Arachis hypogaea L. (Fabales: Fabaceae), sweet potato, Ipomoea batata Lam. (Solanales: Convolvulaceae) or tobacoo in a greenhouse trial, and tobacco field plots with taro rows hosted significantly fewer S. litura than those with rows of other trap crops or without trap crops, provided the taro was in a fast-growing stage. When these crops were grown along with eggplant, Solanum melongena L. (Solanales: Solanaceae), and soybean, Glycines max L. (Fabales: Fabaceae), in separate plots in a randomized matrix, tobacco plots hosted more S. litura than the other crop plots early in the season, but late in the season, taro plots hosted significantly more S. litura than tobacco, soybean, sweet potato, peanut or eggplant plots. In addition, higher rates of S. litura parasitism by Microplitis prodeniae Rao and Chandry (Hymenoptera: Bracondidae) and Campoletis chlorideae Uchida (Ichnumonidae) were observed in taro plots compared to other crop plots. Although taro was an effective trap crop for managing S. litura on tobacco, it did not attract S. litura in the seedling stage, indicating that taro should either be planted 20-30 days before tobacco, or alternative control methods should be employed during the seedling stage.

  14. Inhibition of the responses to sex pheromone of the fall armyworm, Spodoptera frugiperda.

    Science.gov (United States)

    Malo, Edi A; Rojas, Julio C; Gago, Rafael; Guerrero, Ángel

    2013-01-01

    Trifluoromethyl ketones reversibly inhibit pheromone-degrading esterases in insect olfactory tissues, affecting pheromone detection and behavior of moth males. In this work, (Z)-9-tetradecenyl trifluoromethyl ketone (Z9-14:TFMK), a closely-related analogue of the pheromone of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), was prepared and tested in electroantennogram and field tests as possible inhibitors of the pheromone action. The electroantennogram parameters, amplitude, and the repolarization time of the antennal responses of S. frugiperda males were affected by Z9-14:TFMK vapors. Exposure of male antennae to a stream of air passing through 100 μg of the ketone produced a significant reduction of the amplitude and an increase of 2/3 repolarization time signals to the pheromone. The effect was reversible and dose-dependent. In the field, the analogue significantly decreased the number of males caught when mixed with the pheromone in 10:1 ratio. The results suggest that Z9-14:TFMK is a mating disruptant of S. frugiperda and may be a good candidate to consider in future strategies to control this pest.

  15. Mutations in the Bacillus thuringiensis Cry1Ca toxin demonstrate the role of domain II and III in the specificity towards Spodoptera exigua larvae

    NARCIS (Netherlands)

    Herrero Sendra, S.; González-Cabrera, J.; Ferré, J.; Bakker, P.L.; Maagd, de R.A.

    2004-01-01

    Several mutants of the Bacillus thuringiensis Cry1Ca toxin affected with regard to specific activity towards Spodoptera exigua were studied. Alanine was used to replace single residues in loops 2 and 3 of domain II (mutant pPB19) and to replace residues 541-544 in domain III (mutant pPB20). Addition

  16. Natural distribution of parasitoids of larvae of the fall armyworm, Spodoptera frugiperda, in Argentina.

    Science.gov (United States)

    Gabriela Murúa, M; Molina-Ochoa, Jaime; Fidalgo, Patricio

    2009-01-01

    To develop a better understanding of the natural distribution of the fall armyworm, Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae), and to update the knowledge of the incidence of its complex of parasitoids. S. frugiperda, samplings in whorl-stage corn were carried out in provinces of Argentina from 1999 to 2003. S. frugiperda larvae were collected from corn in localities of the provinces of Tucumán, Salta, Jujuy, Santiago del Estero, La Rioja, Córdoba, San Luis, Chaco and Misiones. In each locality 30 corn plants were sampled and only larvae located in those plants were collected. The parasitoids that emerged from S. frugiperda larvae were identified and counted. The abundance of the parasitoids and the parasitism rate were estimated. The S. frugiperda parasitoids collected were Campoletis grioti (Blanchard) (Hymenoptera: Ichneumonidae), Chelonus insularis (Cresson) (Hymenoptera: Braconidae), Archytas marmoratus (Townsend) (Diptera Tachinidae) and/or A. incertus (Macquart), Ophion sp. (Hymenoptera: Ichneumonidae), Euplectrus platyhypenae Howard (Hymenoptera: Eulophidae), and Incamyia chilensis (Aldrich) (Diptera Tachinidae). C. grioti was the most abundant and frequent during the five-year survey. Similar diversity of parasitoids was obtained in all the provinces, with the exception of I. chilensis and E. platyhypenae that were recovered only in the province of Salta. In the Northwestern region, in Tucumán, C. grioti and species of Archytas were the most abundant and frequent parasitoids. On the contrary, in Salta and Jujuy Ch. insularis was the parasitoid most abundant and frequently recovered. The parasitism rate obtained in Tucumán, Salta and Jujuy provinces were 21.96%, 17.87% and 6.63% respectively with an average of 18.93%. These results demonstrate that hymenopteran and dipteran parasitoids of S. frugiperda occurred differentially throughout the Argentinian provinces and played an important role on the natural control of the S. frugiperda larval

  17. Cry1F resistance in fall armyworm Spodoptera frugiperda: single gene versus pyramided Bt maize.

    Directory of Open Access Journals (Sweden)

    Fangneng Huang

    Full Text Available Evolution of insect resistance to transgenic crops containing Bacillus thuringiensis (Bt genes is a serious threat to the sustainability of this technology. However, field resistance related to the reduced efficacy of Bt maize has not been documented in any lepidopteran pest in the mainland U.S. after 18 years of intensive Bt maize planting. Here we report compelling evidence of field resistance in the fall armyworm, Spodoptera frugiperda (J.E. Smith, to Cry1F maize (TC 3507 in the southeastern region of the U.S. An F2 screen showed a surprisingly high (0.293 Cry1F resistance allele frequency in a population collected in 2011 from non-Bt maize in south Florida. Field populations from non-Bt maize in 2012-2013 exhibited 18.8-fold to >85.4-fold resistance to purified Cry1F protein and those collected from unexpectedly damaged Bt maize plants at several locations in Florida and North Carolina had >85.4-fold resistance. In addition, reduced efficacy and control failure of Cry1F maize against natural populations of S. frugiperda were documented in field trials using Cry1F-based and pyramided Bt maize products in south Florida. The Cry1F-resistant S. frugiperda also showed a low level of cross-resistance to Cry1A.105 and related maize products, but not to Cry2Ab2 or Vip3A. The occurrence of Cry1F resistance in the U.S. mainland populations of S. frugiperda likely represents migration of insects from Puerto Rico, indicating the great challenges faced in achieving effective resistance management for long-distance migratory pests like S. frugiperda.

  18. Cry1F resistance in fall armyworm Spodoptera frugiperda: single gene versus pyramided Bt maize.

    Science.gov (United States)

    Huang, Fangneng; Qureshi, Jawwad A; Meagher, Robert L; Reisig, Dominic D; Head, Graham P; Andow, David A; Ni, Xinzi; Kerns, David; Buntin, G David; Niu, Ying; Yang, Fei; Dangal, Vikash

    2014-01-01

    Evolution of insect resistance to transgenic crops containing Bacillus thuringiensis (Bt) genes is a serious threat to the sustainability of this technology. However, field resistance related to the reduced efficacy of Bt maize has not been documented in any lepidopteran pest in the mainland U.S. after 18 years of intensive Bt maize planting. Here we report compelling evidence of field resistance in the fall armyworm, Spodoptera frugiperda (J.E. Smith), to Cry1F maize (TC 3507) in the southeastern region of the U.S. An F2 screen showed a surprisingly high (0.293) Cry1F resistance allele frequency in a population collected in 2011 from non-Bt maize in south Florida. Field populations from non-Bt maize in 2012-2013 exhibited 18.8-fold to >85.4-fold resistance to purified Cry1F protein and those collected from unexpectedly damaged Bt maize plants at several locations in Florida and North Carolina had >85.4-fold resistance. In addition, reduced efficacy and control failure of Cry1F maize against natural populations of S. frugiperda were documented in field trials using Cry1F-based and pyramided Bt maize products in south Florida. The Cry1F-resistant S. frugiperda also showed a low level of cross-resistance to Cry1A.105 and related maize products, but not to Cry2Ab2 or Vip3A. The occurrence of Cry1F resistance in the U.S. mainland populations of S. frugiperda likely represents migration of insects from Puerto Rico, indicating the great challenges faced in achieving effective resistance management for long-distance migratory pests like S. frugiperda.

  19. Effects of neem-based insecticides on beet armyworm (Lepidoptera: Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    SHOILM.GREENBERG; ALLANT.SHOWLER; TONG-XIANLIU

    2005-01-01

    Three commercial neem [Azadirachta indica A. Juss (Meliaceae)]-based insecticides, Agroneem, Ecozin, and Neemix, and a non-commercial neem leaf powder,were evaluated for oviposition deterrence, antifeedant effect on larvae, and toxicity to eggs and larvae of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae),on cotton leaves in the laboratory. Oviposition deterrence in no-choice, and two- and fivechoice assays, was observed for the neem-based insecticide treatments when compared with a non-treated control. Neem-based insecticides also deterred feeding by beet armyworm larvae. Direct contact with neem-based insecticides decreased the survival of beet armyworm eggs. Survival of beet armyworm larvae fed for 7 days on leaves treated with neembased insecticides was reduced to 27, 33, 60, and 61% for neem leaf powder, Ecozin,Agroneem, and Neemix, respectively. Possibilities for adoption of neem-based insecticides in commercial cotton for beet armyworm control are discussed.

  20. Dissimilar Regulation of Antimicrobial Proteins in the Midgut of Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Toxins or Baculovirus

    Science.gov (United States)

    Crava, Cristina M.; Jakubowska, Agata K.; Escriche, Baltasar; Herrero, Salvador; Bel, Yolanda

    2015-01-01

    Antimicrobial peptides (AMPs) and lysozymes are the main effectors of the insect immune system, and they are involved in both local and systemic responses. Among local responses, midgut immune reaction plays an important role in fighting pathogens that reach the insect body through the oral route, as do many microorganisms used in pest control. Under this point of view, understanding how insects defend themselves locally during the first phases of infections caused by food-borne pathogens is important to further improve microbial control strategies. In the present study, we analyzed the transcriptional response of AMPs and lysozymes in the midgut of Spodoptera exigua (Lepidoptera: Noctuidae), a polyphagous pest that is commonly controlled by products based on Bacillus thuringiensis (Bt) or baculovirus. First, we comprehensively characterized the transcripts encoding AMPs and lysozymes expressed in S. exigua larval midgut, identifying 35 transcripts that represent the S. exigua arsenal against microbial infection. Secondly, we analyzed their expression in the midgut after ingestion of sub-lethal doses of two different pore-forming B. thuringiensis toxins, Cry1Ca and Vip3Aa, and the S. exigua nucleopolyhedrovirus (SeMNPV). We observed that both Bt toxins triggered a similar, wide and in some cases high transcriptional activation of genes encoding AMPs and lysozymes, which was not reflected in the activation of the classical systemic immune-marker phenoloxidase in hemolymph. Baculovirus ingestion resulted in the opposed reaction: Almost all transcripts coding for AMPs and lysozymes were down-regulated or not induced 96 hours post infection. Our results shed light on midgut response to different virulence factors or pathogens used nowadays as microbial control agents and point out the importance of the midgut immune response contribution to the larval immunity. PMID:25993013

  1. Dissimilar Regulation of Antimicrobial Proteins in the Midgut of Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Toxins or Baculovirus.

    Science.gov (United States)

    Crava, Cristina M; Jakubowska, Agata K; Escriche, Baltasar; Herrero, Salvador; Bel, Yolanda

    2015-01-01

    Antimicrobial peptides (AMPs) and lysozymes are the main effectors of the insect immune system, and they are involved in both local and systemic responses. Among local responses, midgut immune reaction plays an important role in fighting pathogens that reach the insect body through the oral route, as do many microorganisms used in pest control. Under this point of view, understanding how insects defend themselves locally during the first phases of infections caused by food-borne pathogens is important to further improve microbial control strategies. In the present study, we analyzed the transcriptional response of AMPs and lysozymes in the midgut of Spodoptera exigua (Lepidoptera: Noctuidae), a polyphagous pest that is commonly controlled by products based on Bacillus thuringiensis (Bt) or baculovirus. First, we comprehensively characterized the transcripts encoding AMPs and lysozymes expressed in S. exigua larval midgut, identifying 35 transcripts that represent the S. exigua arsenal against microbial infection. Secondly, we analyzed their expression in the midgut after ingestion of sub-lethal doses of two different pore-forming B. thuringiensis toxins, Cry1Ca and Vip3Aa, and the S. exigua nucleopolyhedrovirus (SeMNPV). We observed that both Bt toxins triggered a similar, wide and in some cases high transcriptional activation of genes encoding AMPs and lysozymes, which was not reflected in the activation of the classical systemic immune-marker phenoloxidase in hemolymph. Baculovirus ingestion resulted in the opposed reaction: Almost all transcripts coding for AMPs and lysozymes were down-regulated or not induced 96 hours post infection. Our results shed light on midgut response to different virulence factors or pathogens used nowadays as microbial control agents and point out the importance of the midgut immune response contribution to the larval immunity.

  2. A larval speciifc OBP able to bind the major female sex pheromone component in Spodoptera exigua (Hübner)

    Institute of Scientific and Technical Information of China (English)

    JIN Rong; LIU Nai-yong; LIU Yan; DONG Shuang-lin

    2015-01-01

    Odorant binding proteins (OBPs) in insects are postulated to solubilize and transport the hydrophobic odorants across the hydrophilic antennal lymph to the olfactory receptors (ORs) located on the dendrite membrane of the sensory neurons. OBPs in adult insects have been intensively reported, but those in larvae are rarely addressed. In our study, a ful-length OBP cDNA, namely SexiOBP13, was cloned by RT-PCR and RACE strategy from the heads of Spodoptera exigua larvae. The quantitative real-time PCR (qPCR) measurement indicated that SexiOBP13 was highly expressed in larval head, but very low in other parts of larva and was not detected in any tissues of adult. The binding afifnities of SexiOBP13 to plant volatiles and female sex pheromone components were measured by competitive binding assays. Interestingly, SexiOBP13 displayed a high binding afifnity (Ki=3.82μmol L–1) to Z9,E12–14:Ac, the major sex pheromone component of S. exigua, while low afifnities to the tested host plant volatiles (Ki>27μmol L–1). The behavioral tests further conifrmed that Z9,E12–14:Ac was indeed active to elicit the behavioral activity of the third instar larvae of S. exigua. Taken together, our results suggest that SexiOBP13 may play a role in reception of female sex pheromone in S. exigua larvae. The ecological signiifcance of the larvae preference to the adult female sex pheromone was discussed.

  3. Dissimilar Regulation of Antimicrobial Proteins in the Midgut of Spodoptera exigua Larvae Challenged with Bacillus thuringiensis Toxins or Baculovirus.

    Directory of Open Access Journals (Sweden)

    Cristina M Crava

    Full Text Available Antimicrobial peptides (AMPs and lysozymes are the main effectors of the insect immune system, and they are involved in both local and systemic responses. Among local responses, midgut immune reaction plays an important role in fighting pathogens that reach the insect body through the oral route, as do many microorganisms used in pest control. Under this point of view, understanding how insects defend themselves locally during the first phases of infections caused by food-borne pathogens is important to further improve microbial control strategies. In the present study, we analyzed the transcriptional response of AMPs and lysozymes in the midgut of Spodoptera exigua (Lepidoptera: Noctuidae, a polyphagous pest that is commonly controlled by products based on Bacillus thuringiensis (Bt or baculovirus. First, we comprehensively characterized the transcripts encoding AMPs and lysozymes expressed in S. exigua larval midgut, identifying 35 transcripts that represent the S. exigua arsenal against microbial infection. Secondly, we analyzed their expression in the midgut after ingestion of sub-lethal doses of two different pore-forming B. thuringiensis toxins, Cry1Ca and Vip3Aa, and the S. exigua nucleopolyhedrovirus (SeMNPV. We observed that both Bt toxins triggered a similar, wide and in some cases high transcriptional activation of genes encoding AMPs and lysozymes, which was not reflected in the activation of the classical systemic immune-marker phenoloxidase in hemolymph. Baculovirus ingestion resulted in the opposed reaction: Almost all transcripts coding for AMPs and lysozymes were down-regulated or not induced 96 hours post infection. Our results shed light on midgut response to different virulence factors or pathogens used nowadays as microbial control agents and point out the importance of the midgut immune response contribution to the larval immunity.

  4. Bacillus thuringiensis insecticidal crystal proteins affect lifespan and reproductive performance of Helicoverpa armigera and Spodoptera exigua adults.

    Science.gov (United States)

    Zhang, Ying; Ma, Yan; Wan, Pin-Jun; Mu, Li-Li; Li, Guo-Qing

    2013-04-01

    Being delivered as sprays or expressed in plant, Bacillus thuringiensis (Bt) crystalline proteins (Cry toxins) display insecticidal activities against numerous Lepidopteran, Dipteran, and Coleopteran larvae. Comparative study of toxicities of Bt Cry toxins between larvae and adults may afford important new insights into the interactions of the toxins with receptor proteins in host insect, and represent intriguing targets for the control of insect pests. However, the effectiveness of Bt Cry toxins in insect adults has paid less attention. In the present article, the effectiveness of Cry1Ac and Cry1Ca on lifespans and reproductive performance of Helicoverpa armigera (Hübner) and Spodoptera exigua (Hübner) adults were evaluated by in vivo experiments. Considering transgenic plants express modified, truncated versions of cry genes yielding active toxin fragment, we used activated Bt toxins at the concentration of 500, 100, and 20 microg/ml in a 10% sucrose aquous solution. At the highest concentration, Cry1Ac and Cry1Ca shortened 48.1 and 48.9% of H. armigera female lifespan, and 43.5 and 38.5% of S. exigua female lifespan, and they reduced 37.8 and 40.3%, and 50.5 and 47.4% of H. armigera and S. exigua male lifespans respectively. Bt toxins negatively affected copulation. Exposure to 500 microg/ml of Cry1Ac and Cry1Ca greatly reduced 50.0 and 46.8%, and 58.7 and 57.3% spermatophore acceptance by H. armigera and S. exigua females, respectively. Similarly, Cry1Ac and Cry1Ca exposure decreased 40.0 and 50.3%, and 61.3 and 60.0% of spermatophore transfer by H. armigera and S. exigua males, respectively. Moreover, exposure females rather than males to 500 microg/ml of Cry1Ac and Cry1Ca significantly dropped 57.5 and 57.5% of the number of eggs laid by H. armigera, and 35.4 and 45.8% of the number of egg masses deposited by S. exigua. In contrast, both Cry1Ac and Cry1Ca did not negatively influence the egg hatchability. At the middle and the lowest concentrations, however

  5. Investigating the molecular mechanisms of organophosphate and pyrethroid resistance in the fall armyworm Spodoptera frugiperda.

    Science.gov (United States)

    Carvalho, Renato A; Omoto, Celso; Field, Linda M; Williamson, Martin S; Bass, Chris

    2013-01-01

    The fall armyworm Spodoptera frugiperda is an economically important pest of small grain crops that occurs in all maize growing regions of the Americas. The intensive use of chemical pesticides for its control has led to the selection of resistant populations, however, to date, the molecular mechanisms underlying resistance have not been characterised. In this study the mechanisms involved in the resistance of two S. frugiperda strains collected in Brazil to chlorpyrifos (OP strain) or lambda-cyhalothrin (PYR strain) were investigated using molecular and genomic approaches. To examine the possible role of target-site insensitivity the genes encoding the organophosphate (acetylcholinesterase, AChE) and pyrethroid (voltage-gated sodium channel, VGSC) target-site proteins were PCR amplified. Sequencing of the S. frugiperda ace-1 gene identified several nucleotide changes in the OP strain when compared to a susceptible reference strain (SUS). These result in three amino acid substitutions, A201S, G227A and F290V, that have all been shown previously to confer organophosphate resistance in several other insect species. Sequencing of the gene encoding the VGSC in the PYR strain, identified mutations that result in three amino acid substitutions, T929I, L932F and L1014F, all of which have been shown previously to confer knockdown/super knockdown-type resistance in several arthropod species. To investigate the possible role of metabolic detoxification in the resistant phenotype of the OP and PYR stains all EST sequences available for S. frugiperda were used to design a gene-expression microarray. This was then used to compare gene expression in the resistant strains with the susceptible reference strain. Members of several gene families, previously implicated in metabolic resistance in other insects were found to be overexpressed in the resistant strains including glutathione S-transferases, cytochrome P450s and carboxylesterases. Taken together these results provide

  6. Investigating the molecular mechanisms of organophosphate and pyrethroid resistance in the fall armyworm Spodoptera frugiperda.

    Directory of Open Access Journals (Sweden)

    Renato A Carvalho

    Full Text Available The fall armyworm Spodoptera frugiperda is an economically important pest of small grain crops that occurs in all maize growing regions of the Americas. The intensive use of chemical pesticides for its control has led to the selection of resistant populations, however, to date, the molecular mechanisms underlying resistance have not been characterised. In this study the mechanisms involved in the resistance of two S. frugiperda strains collected in Brazil to chlorpyrifos (OP strain or lambda-cyhalothrin (PYR strain were investigated using molecular and genomic approaches. To examine the possible role of target-site insensitivity the genes encoding the organophosphate (acetylcholinesterase, AChE and pyrethroid (voltage-gated sodium channel, VGSC target-site proteins were PCR amplified. Sequencing of the S. frugiperda ace-1 gene identified several nucleotide changes in the OP strain when compared to a susceptible reference strain (SUS. These result in three amino acid substitutions, A201S, G227A and F290V, that have all been shown previously to confer organophosphate resistance in several other insect species. Sequencing of the gene encoding the VGSC in the PYR strain, identified mutations that result in three amino acid substitutions, T929I, L932F and L1014F, all of which have been shown previously to confer knockdown/super knockdown-type resistance in several arthropod species. To investigate the possible role of metabolic detoxification in the resistant phenotype of the OP and PYR stains all EST sequences available for S. frugiperda were used to design a gene-expression microarray. This was then used to compare gene expression in the resistant strains with the susceptible reference strain. Members of several gene families, previously implicated in metabolic resistance in other insects were found to be overexpressed in the resistant strains including glutathione S-transferases, cytochrome P450s and carboxylesterases. Taken together these results

  7. Elongation Factor 1β' Gene from Spodoptera exigua: Characterization and Function Identification through RNA Interference

    Directory of Open Access Journals (Sweden)

    Li-Na Zhao

    2012-06-01

    Full Text Available Elongation factor (EF is a key regulation factor for translation in many organisms, including plants, bacteria, fungi, animals and insects. To investigate the nature and function of elongation factor 1β' from Spodoptera exigua (SeEF-1β', its cDNA was cloned. This contained an open reading frame of 672 nucleotides encoding a protein of 223 amino acids with a predicted molecular weight of 24.04 kDa and pI of 4.53. Northern blotting revealed that SeEF-1β' mRNA is expressed in brain, epidermis, fat body, midgut, Malpighian tubules, ovary and tracheae. RT-PCR revealed that SeEF-1β' mRNA is expressed at different levels in fat body and whole body during different developmental stages. In RNAi experiments, the survival rate of insects injected with SeEF-1β' dsRNA was 58.7% at 36 h after injection, which was significantly lower than three control groups. Other elongation factors and transcription factors were also influenced when EF-1β' was suppressed. The results demonstrate that SeEF-1β' is a key gene in transcription in S. exigua.

  8. Efficacy of Spodoptera exigua Multicapsid Nucleopolyhedrovirus on Controlling Vegetable S. exigua in Fields%甜菜夜蛾核型多角体病毒防治蔬菜甜菜夜蛾田间药效试验

    Institute of Scientific and Technical Information of China (English)

    徐爱仙

    2013-01-01

      甜菜夜蛾核型多角体病毒防治蔬菜甜菜夜蛾田间药效试验结果表明,300亿PIB/g甜菜夜蛾核型多角体病毒对甜菜夜蛾有较好的防治效果,且持效期较长,同时可节本增收,对天敌、作物、环境无不良影响,但药效较慢,建议在害虫发生高峰期配合高效低毒低残留农药使用。%In the paper, we studied the control effect of Spodoptera exigua multicapsid nucleopolyhedrovirus against S. exigua in vegetable fields. The results showed that, 3.0×1010 PIB/g S. exigua multicapsid nucleopolyhedrovirus possessed better control effect on S. exigua and longer functioning duration and had no harmful effect on natural enemies, crops and environment, but it worked slowly, so it could be used with high-efficiency, low-toxicity and less persistent pesticides at the peak occourence period of S. exigua.

  9. The Binding Characterization of Cry Insecticidal Proteins to the Brush Border Membrane Vesicles of Helicoverpa armigera, Spodoptera exigua, Spodoptera litura and Agrotis ipsilon

    Institute of Scientific and Technical Information of China (English)

    LU Qiong; CAO Guang-chun; ZHANG Li-li; LIANG Ge-mei; GAO Xi-wu; ZHANG Yong-jun; GUO Yu-yuan

    2013-01-01

    Cry toxins produced by Bacillus thuringiensis (Bt) are effective biological insecticides against certain insect species. However, there are potential risks of the evolved resistance of insects to Cry toxin owing to decreased binding of toxins to target sites in the brush border membranes of the larva midgut. The Cry toxins with different binding sites in the larval midgut have been considered to be a good combination to deploy in delaying resistance evolution. Bioassay results demonstrated that the toxicity of different Cry toxins ranked differently for each species. The toxicity ranking was Cry1Ac>Cry1Ab>Cry2Ab for Helicoverpa armigera, Cry1B>Cry1C>Cry2Ab for Spodoptera exigua, and Cry2Ab>Cry1B>Cry1C for S. litura. Only Cry2Ab was toxic to Agrotis ipsilon. Binding experiments were performed with 125I-Cry1Ab, 125I-Cry1Ac, 125I-Cry1B, 125I-Cry1C, 125I-Cry2Ab and the brush border membranes vesicles (BBMV) from H. armigera, S. exigua, S. litura and A. ipsilon. The binding of Cry1Ab and Cry1Ac was shown to be saturable by incubating with increasing concentrations of H. armigera BBMV (Kd=(45.00±2.01) nmol L-1 and (12.80±0.18) nmol L-1, respectively;Bmax=(54.95±1.79) ng and (55.44±0.91) ng, separately). The binding of Cry1B was shown to be saturable by incubating with increasing concentrations of S. exigua BBMV (Kd=(23.26±1.66) nmol L-1;Bmax=(65.37±1.87) ng). The binding of 125I-Cry toxins was shown to be non-saturable by incubating with increasing concentrations of S. litura and A. ipsilon BBMV. In contrast, Cry1B and Cry1C showed some combination with the BBMV of S. litura, and a certain amount of Cry2Ab could bind to the BBMV of A. ipsilon. These observations suggest that a future strategy could be devised for the focused combination of specific cry genes in transgenic crops to control target pests, widen the spectrum of insecticide effectiveness and postpone insect resistance evolution.

  10. Migratory patterns of the fall armyworm (Spodoptera frugiperda) in the western hemisphere

    Science.gov (United States)

    Fall armyworm (FAW) is a serious pest of sweet corn in south Florida and a pest of other vegetable, row, and forage crops in the southeastern, mid-Atlantic, and central U.S. It is a migratory pest, moving north each season from overwintering areas in southern Texas and southern Florida. For the la...

  11. The Arabidopsis immune regulator SRFR1 dampens defences against herbivory by Spodoptera exigua and parasitism by Heterodera schachtii.

    Science.gov (United States)

    Nguyen, Phuong Dung T; Pike, Sharon; Wang, Jianying; Nepal Poudel, Arati; Heinz, Robert; Schultz, Jack C; Koo, Abraham J; Mitchum, Melissa G; Appel, Heidi M; Gassmann, Walter

    2016-05-01

    Plants have developed diverse mechanisms to fine tune defence responses to different types of enemy. Cross-regulation between signalling pathways may allow the prioritization of one response over another. Previously, we identified SUPPRESSOR OF rps4-RLD1 (SRFR1) as a negative regulator of ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1)-dependent effector-triggered immunity against the bacterial pathogen Pseudomonas syringae pv. tomato strain DC3000 expressing avrRps4. The use of multiple stresses is a powerful tool to further define gene function. Here, we examined whether SRFR1 also impacts resistance to a herbivorous insect in leaves and to a cyst nematode in roots. Interestingly, srfr1-1 plants showed increased resistance to herbivory by the beet army worm Spodoptera exigua and to parasitism by the cyst nematode Heterodera schachtii compared with the corresponding wild-type Arabidopsis accession RLD. Using quantitative real-time PCR (qRT-PCR) to measure the transcript levels of salicylic acid (SA) and jasmonate/ethylene (JA/ET) pathway genes, we found that enhanced resistance of srfr1-1 plants to S. exigua correlated with specific upregulation of the MYC2 branch of the JA pathway concurrent with suppression of the SA pathway. In contrast, the greater susceptibility of RLD was accompanied by simultaneously increased transcript levels of SA, JA and JA/ET signalling pathway genes. Surprisingly, mutation of either SRFR1 or EDS1 increased resistance to H. schachtii, indicating that the concurrent presence of both wild-type genes promotes susceptibility. This finding suggests a novel form of resistance in Arabidopsis to the biotrophic pathogen H. schachtii or a root-specific regulation of the SA pathway by EDS1, and places SRFR1 at an intersection between multiple defence pathways.

  12. The effect of leaf biopesticide Mirabilis jalapa and fungi Metarhizium anisopliae to immune response and mortality of Spodoptera exigua instar IV

    Science.gov (United States)

    Suryani, A. Irma; Anggraeni, Tjandra

    2014-03-01

    Spodoptera exigua is one of insect causing damage in agriculture sector. This insect can be controlled by a natural biopesticide by combining two agents of biological control, biopesticides Mirabilis jalapa and entomopathogenic fungi Metarhizium anisopliae, considered to be virulent toward a wide range of insects. The objective of research was to determine the effect of biopesticides M. jalapa and fungi M. anisopliae against immune system and mortality of S. exigua. This research used a complete randomized block design with five concentrations Mirabilis jalapa and optimum dose of M. anisopliae. A high dose of M. jalapa (0.8% w/v) is the most effective one to decrease total haemocytes especially granulocyt and plasmatocyt (cellular immune) and decrease the concentration of lectin (humoral immune) from S. exigua (p < 0.05). The combination of M. jalapa (0, 8% w/v) and lethal dose of M. anisopliae 2.59 × 107 spore/ml were significant to increase mortality of S. exigua within 48 hours (p < 0.05).

  13. Biological characteristics of black armyworm Spodoptera cosmioides on genetically modified soybean and corn crops that express insecticide Cry proteins

    Directory of Open Access Journals (Sweden)

    Gabriela Vieira Silva

    2016-09-01

    Full Text Available ABSTRACT This study aimed to evaluate the development and reproduction of the black armyworm, Spodoptera cosmioides when larvae fed on leaves of Bt-corn hybrids, expressing a single Cry1F and also Cry1F, Cry1A.105 and Cry2Ab2 in pyramided corn and their non-Bt-isoline (hybrid 2B688, as well as on leaves of two soybean isolines expressing the Cry1Ac protein and its non-Bt isoline (A5547-227. We also assessed the effect of these Bt and non-Bt plants on the leaf consumption rate of S. cosmioides larvae. This pest was unable to develop when fed on any of the corn isolines (Bt and non-Bt. When both 1st and 3rd instar larvae were fed on corn leaf, mortality was 100% in both Bt and non-Bt corn. In contrast, when corn leaves were offered to 5th instar larvae, there were survivors. Defoliation and leaf consumption was higher with non-Bt corn than with both of the Bt corn isolines. There was no negative effect of Bt soybean leaves on the development and reproduction of S. cosmioides with respect to all evaluated parameters. Our study indicates that both Bt and non-Bt corn adversely affect the development of S. cosmioides while Bt soybean did not affect its biology, suggesting that this lepidopteran has major potential to become an important pest in Bt soybean crops.

  14. Vip3A is responsible for the potency of Bacillus thuringiensis 9816C culture supernatant against Helicoverpa armigera and Spodoptera exigua.

    Science.gov (United States)

    Cai, Jun; Xiao, Liang; Yan, Bing; Bin, Guan; Chen, Yuehua; Ren, Gaixin

    2006-04-01

    Culture supernatant of Bacillus thuringiensis 9816C had high toxicity against Helicoverpa armigera and Spodoptera exigua. However, it lost insecticidal activities after being bathed in boiling water for 5 min. Acrystalliferous mutants of Bt9816C (Bt9816C-NP1 and Bt9816C-NP2) cured of its endogenous plasmids no longer possessed vip3A gene and toxicity. The 89 kD protein which existed in Bt9816C supernatant disappeared in the two mutants' supernatant; nevertheless, the two mutants still exhibited hemolytic and phospholipase C activity as Bt9816C did. The vip3A gene of Bt9816C, vip3Aa18, was cloned and expressed in Escherichia coli BL21. Bioassay demonstrated that the recombinant E. coli had high toxicity against S. exigua. Taken together, it suggested that Vip3A protein was responsible for the toxicity of Bt9816C culture supernatants.

  15. Spore stage expression of a vegetative insecticidal gene increase toxicity of Bacillus thuringiensis subsp. aizawai SP41 against Spodoptera exigua.

    Science.gov (United States)

    Thamthiankul Chankhamhaengdecha, S; Tantichodok, A; Panbangred, Watanalai

    2008-09-10

    To enhance the toxicity of the Bacillus thuringiensis subsp. aizawai strain SP41 (SP41), the vegetative insecticidal protein (Vip) gene vip3A from SP41 was redirected to the sporulation stage by replacing its native promoter with the strong promoter P19 of the cry11Aa operon. Compared to the wild type, SP41 with PVIP (vip3A with its native promoter and ter) had the relative expression ratios of 457, 548, and 290 at 8, 14, and 20 h of cultivation, respectively, as measured by quantitative reverse transcription polymerase chain reaction (PCR). SP41 transformed by P19VIP (vip3A controlled by P19 promoter with vip3A ter) showed higher expressions (23, 2055, 1831) at the same time points. SP41 with P19VIP20 (vip3A controlled by P19 promoter and containing P20 and operon ter) had the lowest expression levels (3, 11, 9) at any time point. SDS-PAGE analysis of proteins in the culture supernatant of the P19VIP at 8, 14, and 20 h demonstrated a significant increase in Vip3A at the sporulation stage. Using the surface contamination bioassay, the 50% lethal concentration (LC(50)) of whole culture of PVIP, P19VIP, and P19VIP20 at 20 and 48 h of cultivation against Spodoptera exigua larvae were (68.3, 21.2, and 60.2 microg cm(-2)) and (69.8, 41.8, and 74.6 microg cm(-2)), respectively, compared with 86.6 and 104.4 microg cm(-2) for SP41. The results showed that Vip from P19VIP, expressed at spore stage at 20 and 48 h, can increase the toxicity of SP41 for 4.1- and 2.5-fold, respectively.

  16. Eicosanoids up-regulate production of reactive oxygen species by NADPH-dependent oxidase in Spodoptera exigua phagocytic hemocytes.

    Science.gov (United States)

    Park, Youngjin; Stanley, David W; Kim, Yonggyun

    2015-08-01

    Eicosanoids mediate cellular immune responses in insects, including phagocytosis of invading microbes. Phagocytosis entails two major steps, the internalization of microbes and the subsequent killing of them via formation of reactive oxygen species (ROS). Here, we posed the hypothesis that eicosanoids mediate ROS production by activating NADPH-dependent oxidase (NOX) and tested the idea in the model insect, Spodoptera exigua. A NOX gene (we named SeNOX4) was identified and cloned, yielding a full open reading frame encoding 547 amino acid residues with a predicted molecular weight of 63,410Da and an isoelectric point at 9.28. A transmembrane domain and a large intracellular domain containing NADPH and FAD-binding sites were predicted. Phylogenetic analysis indicated SeNOX4 clusters with other NOX4 genes. SeNOX4 was expressed in all life stages except eggs, and exclusively in hemocytes. Bacterial challenge and, separately, arachidonic acid (AA, a precursor of eicosanoid biosynthesis) injection increased its expression. The internalization step was assessed by counting hemocytes engulfing fluorescence-labeled bacteria. The phagocytic behavior was inhibited by dsRNA suppression of SeNOX4 expression and, separately by dexamethasone (DEX, a specific inhibitor of eicosanoid biosynthesis) treatments. However, injecting AA to dsSeNOX4-treated larvae did not rescue the phagocytic activity. Hemocytic ROS production increased following bacterial challenge, which was sharply reduced in dsSeNOX4-treated, and separately, in DEX-treated larvae. AA partially reversed the suppressed ROS production in dsSeNOX4-treated larvae. Treating larvae with either the ROS-suppressing dsSeNOX4 construct or DEX rendered experimental larvae unable to inhibit bacterial proliferation in their hemocoels. We infer that eicosanoids mediate ROS production during phagocytosis by inducing expression of SeNOX4.

  17. First Report of Outbreaks of the Fall Armyworm Spodoptera frugiperda (J E Smith) (Lepidoptera, Noctuidae), a New Alien Invasive Pest in West and Central Africa

    Science.gov (United States)

    Sankung, Sagnia B.; Togola, Abou; Tamò, Manuele

    2016-01-01

    The fall armyworm Spodoptera frugiperda is a prime noctuid pest of maize on the American continents where it has remained confined despite occasional interceptions by European quarantine services in recent years. The pest has currently become a new invasive species in West and Central Africa where outbreaks were recorded for the first time in early 2016. The presence of at least two distinct haplotypes within samples collected on maize in Nigeria and São Tomé suggests multiple introductions into the African continent. Implications of this new threat to the maize crop in tropical Africa are briefly discussed. PMID:27788251

  18. Nuclear receptors HR96 and ultraspiracle from the fall armyworm (Spodoptera frugiperda), developmental expression and induction by xenobiotics.

    Science.gov (United States)

    Giraudo, Maeva; Audant, Pascaline; Feyereisen, René; Le Goff, Gaëlle

    2013-05-01

    The fall armyworm Spodoptera frugiperda is a major polyphagous pest in agriculture and little is known on how this insect can adapt to the diverse and potentially toxic plant allelochemicals that they ingest or to insecticides. To investigate the involvement of nuclear receptors in the response of S. frugiperda to its chemical environment, we cloned SfHR96, a nuclear receptor orthologous to the mammalian xenobiotic receptors, pregnane X receptor (PXR) and constitutive androstane receptor (CAR). We also cloned ultraspiracle (USP), the ortholog of retinoid X receptor (RXR) that serves as partner of dimerization of PXR and CAR. Cloning of SfUSP revealed the presence of two isoforms, SfUSP-1 and SfUSP-2 in this species, that differ in their N-terminal region. The expression of these receptors as well as the ecdysone receptor was studied during specific steps of development in different tissues. SfHR96 was constitutively expressed in larval midgut, fat body and Malpighian tubules throughout the last two instars and pupal stage, as well as in Sf9 cells. EcR and SfUSP-2 showed peaks of expression before larval moults and during metamorphosis, whereas SfUSP-1 was mainly expressed in the pre-pupal stage. Receptor induction was followed after exposure of larvae or cells to 11 chemical compounds. SfHR96 was not inducible by the tested compounds. EcR was significantly induced by the 20-hydroxyecdysone agonist, methoxyfenozide, and SfUSP showed an increase expression when exposed to the juvenile hormone analog, methoprene. The cloning of these nuclear receptors is a first step in understanding the important capacities of adaptation of this insect pest.

  19. Effects of cyanogenic plants on fitness in two host strains of the fall armyworm (Spodoptera frugiperda).

    Science.gov (United States)

    Hay-Roe, Mirian M; Meagher, Robert L; Nagoshi, Rodney N

    2011-12-01

    The generalist moth, Spodoptera frugiperda (J. E. Smith) consists of two genetic subgroups (host strains) that differ in their distribution among host plant species. The corn strain prefers crop plants such as corn, sorghum, and cotton, while the rice strain is found in small grasses such as Cynodon spp. and rice. Little is known about the physiological factors that drive this host preference. Here, we report a feeding study with natural host plants and an artificial diet containing cyanide. We found that corn, two Cynodon spp. (bermudagrass C. dactylon (L.) Persoon, 'NuMex Sahara', and stargrass C. nlemfuensis var. nlemfuensis Vanderyst, 'Florona'), and a hybrid between bermudagrass and stargrass, 'Tifton 85', exhibited differences in the concentration of the cyanogenic precursors or cyanogenic potential (HCNp) and the release of hydrogen cyanide per unit time or cyanogenic capacity (HCNc). Corn plants released low levels of hydrogen cyanide, while stargrass had greater HCNp/HCNc than bermudagrass and 'Tifton 85'. Feeding studies showed that corn strain larvae experienced higher mortality than the rice strain when fed stargrass or artificial diet supplemented with cyanide. Also, corn strain larvae excreted higher levels of cyanogenic compounds than the rice strain when fed Cynodon spp. These differences in excretion suggest potential disparities in cyanide metabolism between the two strains. We hypothesize that differences in the susceptibility to cyanide levels in various host plants could play a role in driving strain divergence and what appears to be the incipient speciation of this moth.

  20. Cytochrome P450s from the fall armyworm (Spodoptera frugiperda): responses to plant allelochemicals and pesticides.

    Science.gov (United States)

    Giraudo, M; Hilliou, F; Fricaux, T; Audant, P; Feyereisen, R; Le Goff, G

    2015-02-01

    Spodoptera frugiperda is a polyphagous lepidopteran pest that encounters a wide range of toxic plant metabolites in its diet. The ability of this insect to adapt to its chemical environment might be explained by the action of major detoxification enzymes such as cytochrome P450s (or CYP). Forty-two sequences coding for P450s were identified and most of the transcripts were found to be expressed in the midgut, Malpighian tubules and fat body of S. frugiperda larvae. Relatively few P450s were expressed in the established cell line Sf9. In order to gain information on how these genes respond to different chemical compounds, larvae and Sf9 cells were exposed to plant secondary metabolites (indole, indole-3-carbinol, quercetin, 2-tridecanone and xanthotoxin), insecticides (deltamethrin, fipronil, methoprene, methoxyfenozide) or model inducers (clofibrate and phenobarbital). Several genes were induced by plant chemicals such as P450s from the 6B, 321A and 9A subfamilies. Only a few genes responded to insecticides, belonging principally to the CYP9A family. There was little overlap between the response in vivo measured in the midgut and the response in vitro in Sf9 cells. In addition, regulatory elements were detected in the promoter region of these genes. In conclusion, several P450s were identified that could potentially be involved in the adaptation of S. frugiperda to its chemical environment.

  1. SfDronc, an initiator caspase involved in apoptosis in the fall armyworm Spodoptera frugiperda.

    Science.gov (United States)

    Huang, Ning; Civciristov, Srgjan; Hawkins, Christine J; Clem, Rollie J

    2013-05-01

    Initiator caspases are the first caspases that are activated following an apoptotic stimulus, and are responsible for cleaving and activating downstream effector caspases, which directly cause apoptosis. We have cloned a cDNA encoding an ortholog of the initiator caspase Dronc in the lepidopteran insect Spodoptera frugiperda. The SfDronc cDNA encodes a predicted protein of 447 amino acids with a molecular weight of 51 kDa. Overexpression of SfDronc induced apoptosis in Sf9 cells, while partial silencing of SfDronc expression in Sf9 cells reduced apoptosis induced by baculovirus infection or by treatment with UV or actinomycin D. Recombinant SfDronc exhibited several expected biochemical characteristics of an apoptotic initiator caspase: 1) SfDronc efficiently cleaved synthetic initiator caspase substrates, but had very little activity against effector caspase substrates; 2) mutation of a predicted cleavage site at position D340 blocked autoprocessing of recombinant SfDronc and reduced enzyme activity by approximately 10-fold; 3) SfDronc cleaved the effector caspase Sf-caspase-1 at the expected cleavage site, resulting in Sf-caspase-1 activation; and 4) SfDronc was strongly inhibited by the baculovirus caspase inhibitor SpliP49, but not by the related protein AcP35. These results indicate that SfDronc is an initiator caspase involved in caspase-dependent apoptosis in S. frugiperda, and as such is likely to be responsible for the initiator caspase activity in S. frugiperda cells known as Sf-caspase-X.

  2. Cadherin is a functional receptor of bacillus thuringiensis toxin Cry2Aa in the beet armyworm, spodoptera exigua

    Science.gov (United States)

    Bacillus thuringiensis (Bt) insecticidal crystal (Cry) proteins are effective against some insect pests in sprays and transgenic crops, although the evolution of resistance could threaten the long-term efficacy of such Bt use. One strategy to delay resistance to Bt crops is to “pyramid” two or more ...

  3. The Spodoptera exigua (Lepidoptera: Noctuidae) ABCC2 Mediates Cry1Ac Cytotoxicity and, in Conjunction with Cadherin, Contributes to Enhance Cry1Ca Toxicity in Sf9 Cells.

    Science.gov (United States)

    Ren, Xiang-Liang; Jiang, Wei-Li; Ma, Ya-Jie; Hu, Hong-Yan; Ma, Xiao-Yan; Ma, Yan; Li, Guo-Qing

    2016-12-01

    In insects, the mode of Cry1A toxins action has been studied in detail and many receptors that participate in the process are known. Recent evidence has revealed that an ABC transporter (ABCC2) is involved in conferring resistance to Cry1A toxins and that ABCC2 could be a receptor of Cry1A. However, it is not known whether Cry1Ca interacts with the same receptor proteins as Cry1A. In this study, we report the cloning of an ABC transporter gene, SeABCC2b, from the midgut of Spodoptera exigua (Hübner) larvae, and its expression in Sf9 cells for a functional analysis. The addition of Cry1Ca and Cry1Ac to Sf9 cell culture caused swelling in 28.5% and 93.9% of the SeABCC2-expressing cells, respectively. In contrast, only 7.4% and 1.3% of the controls cells swelled in the presence of Cry1Ca and Cry1Ac. Thus, SeABCC2b-expressing Sf9 cells had increased susceptibility to Cry1Ca and Cry1Ac. Similarly, S. exigua cadherin (SeCad1b) expressed in Sf9 cells caused 47.1% and 1.8% of the SeCad1b-expressing cells to swell to Cry1Ca and Cry1Ac exposure. Therefore, Sf9 cells expressing SeCad1b were more sensitive to Cry1Ca than Cry1Ac. Together, our data suggest that SeABCC2b from S. exigua mediates Cry1Ac cytotoxicity and, in conjunction with SeCad1b, contributes to enhance Cry1Ca toxicity in Sf9 cells.

  4. Lethal and sublethal effects of methoxyphenozide on the development, survival and reproduction of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

    Energy Technology Data Exchange (ETDEWEB)

    Zarate, N.; Diaz, O. [Universidad Autonoma de San Luis Potosi (Mexico). Facultad de Agronomia; Martinez, A.M.; Figueroa, J.I.; Pineda, S., E-mail: spineda_us@yahoo.co [Universidad Michoacana de San Nicolas de Hidalgo, Tarimbaro, Michoacan (Mexico). Inst. de Investigaciones Agropecuarias y Forestales; Schneider, M.I. [National Council of Scientific and Technical Research (CEPAVE/CCT/CONICET), La Plata (Argentina). Centro de Estudios Parasitologicos y de Vectores. Centro Cientifico Tecnologico; Smagghe, G. [Ghent University, Ghent (Belgium). Faculty of Bioscience Engineering. Lab of Agrozoology; Vinuela, E.; Budia, F. [Escuela Tecnica Superior de Ingenieros Agronomos, Madrid (Spain). Escuela Tecnica Superior de Ingenieros Agronomos. Proteccion de Cultivos

    2011-01-15

    The lethal and sublethal effects of the ecdysone agonist methoxyphenozide on the fall armyworm, Spodoptera frugiperda (J. E. Smith), were investigated by feeding a methoxyphenozide-treated diet to fifth instars until pupation in doses corresponding to the LC{sub 10} and LC{sub 25} for the compound. Larval mortality reached 8% and 26% in the low and high concentration groups, respectively, on the seventh day of the experiment. A progressive larval mortality of 12% for the LC{sub 10} and 60% for the LC{sub 25} was observed before pupation. Treated larvae exhibited lower pupal weights, higher pupal mortality, presence of deformed pupae, and more deformed adults than untreated larvae. The incorporation of methoxyfenozide into the diet had a significant effect on the timing of larval development. The development period for males and females was about seven days longer than the controls for both concentrations tested. In contrast, the compound affected neither pupae nor adult longevity. Finally, S. frugiperda adults that resulted from fifth instars treated with methoxyfenozide were not affected in their mean cumulative number of eggs laid per female (fecundity), nor percentages of eggs hatched (fertility), or the sex ratio. Our results suggest that the combination of lethal and sublethal effects of methoxyfenozide may have important implications for the population dynamics of the fall armyworm. (author)

  5. Study on Olfactory Behavior of Spodoptera exigua on Rosa chinensis Infected by Podosphaera pannosa%甜菜夜蛾对白粉菌侵染的中国月季的嗅觉行为研究

    Institute of Scientific and Technical Information of China (English)

    苏艳梅; 罗恒飞; 杨斌; 杨德强; 李向红; 杨发忠

    2011-01-01

    The influence and its spacial effect of Podosphaera pannosa-infection on Spodoptera exigua adult on Rosa chinensis plant were determined by using olfactometer. According to the number of response insects, the beet armyworm moths were significantly attracted by the volatiles emitted from healthy leaf tissues of roses (P =0. 002 ), while the females were obviously repelled by the volatiles emitted from infected leaves (P = 0.006 ), when compared to the clean air control. And the moths showed the significant differences between healthy and infected leaves (P = 0. 000). Therefore, the female's choosing for oviposition site was significantly inhibited by P. pannosa-infection. Further bioassays were conducted to elucidate the spacial scale .of the effect of this inhibition. In consequence, the obviously local and systemic effects were found: the local effect expanded within one leaf and the systemic effect expanded one leaf position up and down. The study will provide further basis for further study on selection mechanism of oviposition.%采用Y型嗅觉仪测试了白粉菌侵染中国月季对甜菜夜蛾成虫嗅觉行为的影响及这种影响的空间效应.根据反应虫数分析,健康叶片挥发性成分对甜菜夜蛾成虫有显著的引诱作用(P=0.002),同时感病叶片挥发性成分对雌蛾有显著的驱避作用(P=0.006),直接比较2种叶片时差异更显著(P=0.000).通过植物介导,中国月季感染白粉菌对甜菜夜蛾成虫产卵地的选择有明显抑制作用.进一步的空间效应研究结果显示,这种抑制作用存在局部效应和系统效应,能在同小叶内传递,并能向上或向下传递至同叶轴的其他相邻小叶,该研究为甜菜夜蛾成虫产卵地选择机制的深入研究提供了重要依据.

  6. Using satellite multispectral imagery for damage mapping armyworm (Spodoptera frugiperda) in maize damage at a regional scale

    Science.gov (United States)

    Armyworm, as a destructive insect for maize, causes wide range of damage in both China and U.S. in recent years. To obtain the spatial distribution of damage area and assess the damage severity, a fast and accurate loss assessment method is of great importance for effective management. This study, t...

  7. Impact of UV radiation on activity of linear furanocoumarins and Bacillus thuringiensis var. kurstaki against Spodoptera exigua: Implications for tritrophic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Trumble, J.T.; Moar, W.J.; Brewer, M.J.; Carson, W.G. (Univ. of California, Riverside (United States))

    1991-05-01

    Acidic fogs with a pH of 2.0 and duration of 2 hr did not reduce the efficacy of Bacillus thuringiensis var. kurstaki. Therefore, the impact of UV radiation was investigated on the interactions between (1) levels of the antibacterial linear furanocoumarins psoralen, bergapten, and xanthotoxin in Apium graveolens (L.) occurring following a 2.0 pH acidic fog episode, (2) the noctuid Spodoptera exigua, and (3) a sublethal dosage of the microbial pathogen B. thuringiensis var. kurstaki. Mean time to pupation in the absence of UV radiation was significantly extended by the addition of either psoralens or B. thuringiensis. Larvae developing on diets containing B. thuringiensis plus psoralens required nearly 40% longer to pupate than controls, but their effects were additive as the interaction was not significant. Mean time to mortality, a weighted average time of death, was not significantly affected by any of the treatments. In a 2 {times} 2 {times} 2 factorial analysis, all main effects reduced survival significantly, as did the three-way interaction. Thus, antagonistic interactions with psoralens that would reduce the effectiveness of B. thuringiensis in the field were not observed. When pairs of main effects were nested within the two levels of the third factor, several two-way interactions were found. Interestingly, the activity of B. thuringiensis and the psoralens, individually or in combination, was enhanced by exposure to UV radiation. Implications of this research are discussed for both natural and agricultural ecosystems.

  8. Sorghum seed maturity affects the weight and feeding duration of immature corn earworm, Helicoverpa zea, and fall armyworm, Spodoptera frugiperda, in the laboratory.

    Science.gov (United States)

    Soper, Alysha M; Whitworth, R Jeff; McCornack, Brian P

    2013-01-01

    Corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noctuidae), and fall armyworm, Spodoptera frugiperda J.E. Smith, are occasional pests in sorghum, Sorghum bicolor L. Moench (Poales: Poaceae), and can be economically damaging when conditions are favorable. Despite the frequent occurrence of mixed-species infestations, the quantitative data necessary for developing yield loss relationships for S. frugiperda are not available. Although these species share similar biological characteristics, it is unknown whether their damage potentials in developing grain sorghum panicles are the same. Using no-choice feeding assays in the laboratory, this study examined larval growth and feeding duration for H. zea and S. frugiperda in the absence of competition. Each species responded positively when exposed to sorghum seed in the soft-dough stage, supporting evidence for the interactions between host-quality and larval growth and development. The results of this study also confirmed the suitability of using laboratory-reared H. zea to develop sorghum yield loss estimates in the field, and provided insights into the biological responses of S. frugiperda feeding on developing sorghum seed.

  9. Isolation and identification of a new pathogenic bacterium strain for Spodoptera exigua H(u)nber%一种新的甜菜夜蛾致病菌的分离和鉴定

    Institute of Scientific and Technical Information of China (English)

    齐放军; 刘缨; 季志英

    2004-01-01

    近年来甜菜夜蛾Spodoptera exigua Hünber对我国农业生产的危害日趋严重,其抗药性发展甚为迅速,化学农药对其防治效果不佳,国内外尚缺乏能够有效防治甜菜夜蛾的生防菌资源。为此,我们进行了从自然罹病死亡的甜菜夜蛾中分离和筛选致病菌的初步研究。

  10. Studies on fall armyworm migration and monitoring

    Science.gov (United States)

    Spodoptera frugiperda (J.E. Smith; Lepidoptera: Noctuidae) or fall armyworm is an important agricultural pest of a number of crops in thewestern hemisphere. Two morphologically identical host strains of fall armyworm exist, the rice-strain and corn-strain, with the latter inflicting substantial eco...

  11. Temporal allocation of metabolic tolerance in the body of beet armyworm in response to three gossypol-cotton cultivars

    Institute of Scientific and Technical Information of China (English)

    Marvin; K; HARRIS

    2009-01-01

    The nutrient composition and enzyme activities in larvae of the beet armyworm, Spodoptera exigua (Hbner), fed on high, medium or low gossypol cotton cultivars were examined at different time intervals. Significantly lower free fatty acid was observed in larvae fed for 6 h on high gossypol ’M9101’ compared to larvae fed on the low (ZMS13) and intermediate (HZ401) gossypol cultivars. Significantly higher trypsin activity was observed in larvae fed on high gossypol ’M9101’ for 24 h compared to those fed for 1, 4 and 6 h. Significantly higher catalase and total superoxide dismutase enzyme activities were observed in larvae of S. exigua fed on high gossypol ’M9101’ compared with low gossypol cultivars ’ZMS13’ and ’HZ401’ for 1, 4, 6 and 24 h. However, significantly lower carboxylesterase and acetylcholinesterase enzyme activities were found in larvae fed on high gossypol ’M9101’ compared with the other cultivars for 1, 4, 6 and 24 h. The interaction between cotton variety and beet armyworm infestation time significantly affected the carboxylesterase enzyme activity in S. exigua. The characterization of the effects of plant allelochemicals on herbivorous larvae is important for aiding understanding of plant-insect interaction as well as in devising solutions to pest problems by breeding plant resistance, identifying metabolic targets for insecticide development, etc.

  12. Sustainable synthesis of flavonoid derivatives, QSAR study and insecticidal activity against the fall armyworm, Spodoptera frugiperda (Lep.: Noctuidae).

    Science.gov (United States)

    Romanelli, Gustavo P; Virla, Eduardo G; Duchowicz, Pablo R; Gaddi, Ana L; Ruiz, Diego M; Bennardi, Daniel O; Del Valle Ortiz, Erlinda; Autino, Juan C

    2010-05-26

    A simple, clean, solvent-free preparation of flavones by the use of a silica-supported Preyssler heteropolyacid as reusable catalyst is described. High selectivity and very good yields (87-94%) were obtained in short reaction times (7-13 min). Bioassays for insecticidal activity against Spodoptera frugiperda were carried out with a set of flavones. Bioassays showed that some of the flavones had moderate insecticidal activity. Quantitative structure-activity relationships were established on the available data with the purpose of predicting the insecticidal activity of a number of structurally related flavones. A relationship between the molecular structure and biological activity is proposed.

  13. AUTOCORRELAÇÃO ESPACIAL NA AVALIAÇÃO DE COMPOSTOS DE MILHO PARA RESISTÊNCIA À LAGARTA DO CARTUCHO (Spodoptera frugiperda SPATIAL AUTOCORRELATION IN THE EVALUATION OF MAIZE COMPOSITES FOR RESISTANCE TO FALL ARMYWORM (Spodoptera frugiperda

    Directory of Open Access Journals (Sweden)

    José Branco de Miranda Filho

    2007-09-01

    Full Text Available

    Foram gerados três compostos de milho (CRL-01, CRL-02 e CRL-03 entre materiais adaptados e materiais exóticos, com históricos de resistência à lagarta do cartucho (Spodoptera frugiperda. Famílias de irmãos germanos dos três compostos foram avaliadas para resistência à lagarta, usando uma escala de notas variando de 0 (sem danos a 5 (cartucho destruído. O delineamento experimental usado foi o de blocos completos casualizados com duas repetições. Dois modelos foram considerados: um modelo com erros independentes e outro assumindo erros espacialmente correlacionados (análise espacial. Na análise espacial a matriz de covariâncias de resíduos (R foi construída conforme a autocorrelação espacial detectada em cada experimento. O teste de Durbin-Watson foi usado para verificar presença da autocorrelação espacial entre parcelas, a qual foi altamente significativa. O alcance prático da autocorrelação espacial foi de cerca 1,5 m. A adoção da análise espacial permitiu uma melhoria no controle da variação local, resultando numa redução das estimativas das variâncias residuais e, conseqüentemente, num aumento dos coeficientes de herdabilidade estimados, com melhorias nos ganhos esperados com a seleção. O ordenamento das progênies foi alterado dependendo da escolha do modelo de análise. A analise espacial, nessas circunstâncias, foi mais apropriada que a análise com erros independentes.

    PALAVRAS-CHAVE: Germoplasma exótico; autocorrelação espacial; modelos mistos; BLUP.

    Composites of maize (CRL-01, CRL-02 and CRL-03 were synthesized from crosses of adapted materials with exotic materials that have shown resistance to fall armyworm (Spodoptera frugiperda. Full-sib progenies from the three composites were evaluated for

  14. Fall Armyworm in the Southeast

    Science.gov (United States)

    Two separate experiments testing fall armyworm (Spodoptera frugiperda) migration patterns were set up in the southeastern U.S. in 2012. Previous results showed that moths from progeny of overwintering populations from south Texas were found west of the Chattahoochee-Flint-Apalachicola river basin, ...

  15. Cross-Resistance between Cry1 Proteins in Fall Armyworm (Spodoptera frugiperda May Affect the Durability of Current Pyramided Bt Maize Hybrids in Brazil.

    Directory of Open Access Journals (Sweden)

    Daniel Bernardi

    Full Text Available Genetically modified plants expressing insecticidal proteins from Bacillus thuringiensis (Bt offer valuable options for managing insect pests with considerable environmental and economic benefits. Despite the benefits provided by Bt crops, the continuous expression of these insecticidal proteins imposes strong selection for resistance in target pest populations. Bt maize (Zea mays hybrids have been successful in controlling fall armyworm (Spodoptera frugiperda, the main maize pest in Brazil since 2008; however, field-evolved resistance to the protein Cry1F has recently been reported. Therefore it is important to assess the possibility of cross-resistance between Cry1F and other Cry proteins expressed in Bt maize hybrids. In this study, an F2 screen followed by subsequent selection on MON 89034 maize was used to select an S. frugiperda strain (RR able to survive on the Bt maize event MON 89034, which expresses the Cry1A.105 and Cry2Ab2 proteins. Field-collected insects from maize expressing the Cry1F protein (event TC1507 represented most of the positive (resistance allele-containing (isofamilies found. The RR strain showed high levels of resistance to Cry1F, which apparently also conferred high levels of cross resistance to Cry1A.105 and Cry1Ab, but had only low-level (10-fold resistance to Cry2Ab2. Life history studies to investigate fitness costs associated with the resistance in RR strain revealed only small reductions in reproductive rate when compared to susceptible and heterozygous strains, but the RR strain produced 32.2% and 28.4% fewer females from each female relative to the SS and RS (pooled strains, respectively. Consistent with the lack of significant resistance to Cry2Ab2, MON 89034 maize in combination with appropriate management practices continues to provide effective control of S. frugiperda in Brazil. Nevertheless, the occurrence of Cry1F resistance in S. frugiperda across Brazil, and the cross-resistance to Cry1Ab and Cry1A

  16. Fitness costs of Cry1F resistance in two populations of fall armyworm, Spodoptera frugiperda (J.E. Smith), collected from Puerto Rico and Florida.

    Science.gov (United States)

    Dangal, Vikash; Huang, Fangneng

    2015-05-01

    The development of resistance in target pest populations is a threat to the sustainability of transgenic crops expressing Bacillus thuringiensis (Bt) proteins. Fall armyworm, Spodoptera frugiperda (J.E. Smith), is a major target pest of Bt maize in North and South America. This insect is the first target pest that has developed field resistance to Bt maize at multiple locations in these regions. The objective of this study was to assess the fitness costs associated with the Cry1F resistance in two populations of S. frugiperda collected from Puerto Rico (RR-PR) and Florida (RR-FL). In the study, fitness costs were evaluated by comparing survival, growth, and developmental time of seven populations of S. frugiperda on (1) non-Bt meridic diet and (2) non-Bt maize leaf tissue and non-Bt diet. The seven populations were RR-PR, RR-FL, a Bt-susceptible strain (Bt-SS), and four F1 populations developed from reciprocal crosses between Bt-SS and the two resistant populations. Biological parameters measured were neonate-to-adult survivorship, neonate-to-adult developmental time, 10day larval weight on non-Bt maize leaf tissue, pupal weight, and sex ratios. Results of the study show that the Cry1F resistance in both RR-PR and RR-FL was associated with considerable fitness costs, especially for the Florida population. Compared to the Bt-susceptible population, RR-PR showed an average of 61.1% reduction in larval weight, 20.4% less in neonate-to-adult survivorship, and 3.7days delay in neonate-to-adult developmental time. These fitness costs for RR-FL were 66.9%, 31.7% and 4.4days, respectively. The fitness costs of RR-PR and RR-FL appeared to be non-recessive. The results indicate that a diversified genetic basis may exist for the Cry1F resistance in S. frugiperda.

  17. Cross-Resistance between Cry1 Proteins in Fall Armyworm (Spodoptera frugiperda) May Affect the Durability of Current Pyramided Bt Maize Hybrids in Brazil.

    Science.gov (United States)

    Bernardi, Daniel; Salmeron, Eloisa; Horikoshi, Renato Jun; Bernardi, Oderlei; Dourado, Patrick Marques; Carvalho, Renato Assis; Martinelli, Samuel; Head, Graham P; Omoto, Celso

    2015-01-01

    Genetically modified plants expressing insecticidal proteins from Bacillus thuringiensis (Bt) offer valuable options for managing insect pests with considerable environmental and economic benefits. Despite the benefits provided by Bt crops, the continuous expression of these insecticidal proteins imposes strong selection for resistance in target pest populations. Bt maize (Zea mays) hybrids have been successful in controlling fall armyworm (Spodoptera frugiperda), the main maize pest in Brazil since 2008; however, field-evolved resistance to the protein Cry1F has recently been reported. Therefore it is important to assess the possibility of cross-resistance between Cry1F and other Cry proteins expressed in Bt maize hybrids. In this study, an F2 screen followed by subsequent selection on MON 89034 maize was used to select an S. frugiperda strain (RR) able to survive on the Bt maize event MON 89034, which expresses the Cry1A.105 and Cry2Ab2 proteins. Field-collected insects from maize expressing the Cry1F protein (event TC1507) represented most of the positive (resistance allele-containing) (iso)families found. The RR strain showed high levels of resistance to Cry1F, which apparently also conferred high levels of cross resistance to Cry1A.105 and Cry1Ab, but had only low-level (10-fold) resistance to Cry2Ab2. Life history studies to investigate fitness costs associated with the resistance in RR strain revealed only small reductions in reproductive rate when compared to susceptible and heterozygous strains, but the RR strain produced 32.2% and 28.4% fewer females from each female relative to the SS and RS (pooled) strains, respectively. Consistent with the lack of significant resistance to Cry2Ab2, MON 89034 maize in combination with appropriate management practices continues to provide effective control of S. frugiperda in Brazil. Nevertheless, the occurrence of Cry1F resistance in S. frugiperda across Brazil, and the cross-resistance to Cry1Ab and Cry1A.105

  18. Revisión de los hospederos del gusano cogollero del maíz, Spodoptera frugiperda (Lepidoptera: Noctuidae Review of the host plants of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Augusto Casmuz

    2010-12-01

    Full Text Available Con la finalidad de actualizar los hospederos citados para Spodoptera frugiperda (J. E. Smith, se realizó una revisión bibliográfica. La búsqueda de hospederos fue agrupada por zona y país. Para el norte del Continente Americano, se incluyeron las citas encontradas para EE.UU., México, América Central e islas del Caribe. En Sudamérica, se agruparon todos los países del cono sur, a excepción de la Argentina, la cual fue considerada por separado. Se encontraron un total de 186 hospederos, repartidos en 42 familias. Entre los hospederos más citados, el 35,5% perteneció a la familia Poaceae, el 11,3% a la familia Fabaceae, a la familia Solanaceae y Asteraceae un 4,3 % cada una, siguiéndoles las Rosaceae y Chenopodiaceae con un 3,7% cada una y, finalmente, las Brassicaceae y Cyperaceae con un 3,2%. Del total de plantas encontradas (186 el 64% se hallaron presentes en Norteamérica y Centroamérica, un 53% en Sudamérica y un 32% en Argentina. Las especies más citadas fueron (en orden decreciente para Norteamérica: maíz, sorgo, maní, grama bermuda, caña de azúcar y arroz; para Sudamérica: maíz, arroz, sorgo, poroto, algodón y maní; y por último, en Argentina fueron: maíz, soja, algodón, alfalfa, tomate, lino, papa y sorgo. También se aporta información sobre su ciclo de vida, hábitos y comportamiento sobre los principales hospederos, migración y biotipos.In order to update records of Spodoptera frugiperda (J. E. Smith host plants, a bibliographic review was made. Host plant search was organized into groups per zones and countries. Records from the U.S., Mexico, Central America and the Caribbean Islands were grouped together as belonging to Northern America. As South American records, all reports were included except for those from Argentina. 186 host plants were found and they belong to 42 different families. The most cited hosts are part of the following families: Poaceae (35.5%, Fabaceae (11.3%, Solanaceae and

  19. Pathogenicity of Beauveria bassiana to Spodoptera exigua Larvae at Different Temperature and Humidity%不同温湿度下球孢白僵菌对甜菜夜蛾幼虫的致病力

    Institute of Scientific and Technical Information of China (English)

    崔璟辉; 谭周进; 陈浩涛

    2012-01-01

    The pathogenieity of Beauveria bassiana to Spodoptera exigua larvae at different temperature and humidity indoors was studied. The results showed that temperature, relative humidity and larval instar had significant impacts on the pathogenicity of Beauveria bassiana. The temperature range 24 - 27 ℃ , the relative humidity more than 90% and lower larval instar were the most suitable conditions for the infection of Beauveria bassiana to Spodoplera exigua larvae.%在室内研究了球孢白僵菌在不同温度和湿度条件下对甜菜夜蛾幼虫的致病力,结果表明:温度、相对湿度、幼虫龄期对白僵菌的致病力具有显著的影响,24~27℃是球孢白僵菌感染甜菜夜蛾的最适宜温度;相对湿度大于90%,甜菜夜蛾的幼虫虫龄越低,越有利于球孢白僵菌对幼虫的感染.

  20. Towards onions and shallots (Allium cepa L.) resistant to beet armyworm (Spodoptera exigua Hübner) by transgenesis and conventional breeding

    NARCIS (Netherlands)

    Zheng, S.J.

    2000-01-01

    Onion ( Allium cepa L. group Common Onion) and shallot ( A. cepa L. group Aggregatum) are two subspecies of A. cepa . Both onion and shallot together with other Allium species like garlic ( A. sativum ), leek ( A. porrum ) and bunching onion ( A. fistulosum ) are very important vegetable crops on a

  1. 温湿度和幼虫饥饿胁迫对白僵菌毒杀甜菜夜蛾效果的影响%Effects of Temperature, Humidity and Starvation Stress on the Virulence of Beauveria bassiana against the Larvae of Spodoptera exigua

    Institute of Scientific and Technical Information of China (English)

    崔璟辉; 陈浩涛

    2012-01-01

    In this paper, the effects of temperature, humidity and starvation stress on the virulence of Beauveria bassiana against the larvae of Spodoptera exigua in laboratory were studied. The results showed that the temperature and the humidity had significant impact on the virulence of Beauveria bassiana, range of 24-27℃ and humid environment were beneficial to that Beauveria bassiana infecting the larvae of Spodoptera exigua; The starvation stress could shorten the time of Beauveria bassiana killing the larvae of Spodoptera exigua significantly. Therefore, weather factors such as temperature and humidity, food intake of pests, age of the Larvae must be considered when made use of Beauveria bassiana to prevent the larvae of Spodoptera exigua, and the best control effect could be achieved.%为了研究温、湿度和饥饿胁迫对白僵菌防治甜菜夜蛾幼虫的影响,进行了室内试验.结果表明:温度对白僵菌的致病力有显著影响,24~27℃下有利于白僵菌感染甜菜夜蛾幼虫;湿度对白僵菌的致病力也有显著影响,高湿环境有利于白僵菌感染甜菜夜蛾幼虫;饥饿胁迫能显著缩短甜菜夜娥幼虫被白僵菌杀死的时间.因此,在利用白僵菌防治甜菜夜蛾幼虫时,只有充分考虑温、湿度等天气因素,害虫的食物摄取,幼虫虫龄等基本情况,才能取得最佳的防治效果.

  2. Under-estimate in a moth biodiversity measurement owing to a migratory event of Spodoptera exigua%甜菜夜蛾的迁徙导致对蛾类生物多样的估计过低

    Institute of Scientific and Technical Information of China (English)

    Leonardo DAPPORTO; Francesca MAGI; Stefania NAPPINI; Rosalba BANCHETTI

    2005-01-01

    由于蛾类易于采集和鉴定,因而在进行生物多样性调查时,它们成为研究最多的动物类群之一.由于大多数蛾类可以通过灯光诱捕,因此生物多样性研究中普遍采用灯光诱捕法.在抽样样本中,夜蛾科常常所占个体比例最多,该科包括一些著名的迁徙物种,有时捕获的个体数量相当高.本文阐述了2003年发生在托斯卡纳的甜菜夜蛾(Spodoptera exigua)迁徙事件.我们在抽样中发现了大批甜菜夜蛾的标本,从而使这一地区的生物多样性实际值发生了很大改变.因此,我们认为,在对蛾类进行生物多样性调查时,在分析时应该剔除可能涉及到迁徙的物种

  3. Effect of fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) strain and diet on oviposition and development in the parasitoid Euplectrus platyhypenae (Hymenoptera: Eulophidae)

    Science.gov (United States)

    Oviposition tendency and subsequent development of the parasitoid wasp Euplectrus platyhypenae Howard was compared using the corn and rice host strains of Spodoptera frugiperda (J. E. Smith) fed corn (Zea mays, ‘Truckers Favorite’) or stargrass (Cynodon nlemfuensis Vanderyst var. nlemfuensis, ‘Floro...

  4. Interação silício com inseticida regulador de crescimento no manejo da lagarta-do-cartucho Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae em milho Interaction of silicon with growth regulating insecticide in the management of fall armyworm Spodoptera frugiperda (J. E. SMITH, 1797 (Lepidoptera: Noctuidae in corn plants

    Directory of Open Access Journals (Sweden)

    Danila Kelly Pereira Neri

    2005-12-01

    Full Text Available Com o objetivo de avaliar o efeito do silício aplicado via solo e foliar, bem como sua interação com o inseticida regulador de crescimento (lufenuron no manejo de Spodoptera frugiperda em plantas de milho, foi realizado um ensaio em casa-de-vegetação e em laboratório, constando de nove tratamentos com cinco repetições. No laboratório do Departamento de Entomologia da Universidade Federal de Lavras-MG, avaliou-se a preferência das lagartas por folhas destacadas de plantas de milho provenientes dos diferentes tratamentos, bem como o consumo e a mortalidade dessa praga. Em casa-de-vegetação, foram avaliadas a intensidade das injúrias provocadas pelas lagartas nas folhas, utilizando uma escala visual de danos proposta por Davis & Williams (1989, bem como o número e a biomassa das lagartas vivas. Pelos resultados pode-se concluir que os tratamentos não afetaram a preferência da lagarta-do-cartucho em teste de livre escolha. A interação silício e lufenuron no manejo de S. frugiperda é positiva em relação ao inseticida isolado, provavelmente devido a resistência mecânica conferida pelo silício as folhas.The objective of this work was to evaluate the effect of sprayed silicon via soil and leaf as well as its interaction with growth regulating insecticide (lufenuron in the management of Spodoptera frugiperda on corn plants. The trials were carried out in greenhouse and laboratory conditions and consisting of nine treatments with five replicates. In the laboratory, the preference of fall armyworms on detached leaves of corn plants from different treatments was evaluated, as well as the consumption and mortality of this pest. In the greenhouse, the damage caused by the insect on the leaves were evaluated by using a visual scale of injuries proposed by Davis & Williams (1989. In the greenhouse on the control treatment, both the number and weight of the larval were also determined. According to the results, silicon, the insecticide

  5. 武汉地区甜菜夜蛾发生动态与气象因子关系初探%Preliminary study on the relationship between the population dynamics of Spodoptera exigua and the main meteorological condition in Wuhan area

    Institute of Scientific and Technical Information of China (English)

    杨文刚; 周利琳; 孟翠丽; 陈鑫; 望勇; 司升云

    2016-01-01

    采用性诱法、灯诱法及田间调查法对2009-2010年武汉地区甜菜夜蛾成虫、幼虫开展动态监测,结果表明:武汉地区甜菜夜蛾成虫、幼虫主高峰出现在8-10月。根据同时期逐日的气象数据,探讨了武汉地区甜菜夜蛾越冬及成虫高峰日前期气象条件。甜菜夜蛾在武汉越冬虫源存活率低,高温少雨日照多有利于甜菜夜蛾成虫暴发。本研究为进一步探讨甜菜夜蛾在全国范围内迁飞和种群消长提供支撑,为实现基于气象预报的甜菜夜蛾发生测报奠定基础。%The population dynamics of Spodoptera exigua adults and larvae from 2009 to 2010 in Wuhan area were monitored with synthetic sex pheromone lures,multi-frequency vibration-killing lamps,and field investigation method.The results showed that the peak of both S .exigua adults and larvae appeared from August to October. The daily meteorological data were used to analyze the meteorological conditions during the overwintering period and the pre-peak period of S .exigua adult.The results showed that the survival rate of overwintering S .exigua was very low.The high temperature,less rainfall and rich sunlight were beneficial to S.exigua adult outbreak.This study provides a strong support to advance research of the diffusion and migration of S.exigua adult in nationwide,and lays a foundation for monitoring and forecasting of S.exigua based on meteorological grade prediction.

  6. Feeding deterrence and inhibitory effects of bee balm (Monarda didyma) leaves on fall armyworm

    Science.gov (United States)

    The fall armyworm [Spodoptera frugiperda (J.E. Smith)] is a serious pest of many field and horticulture crops. Because of the many advantages for the use of plant-derived pesticides, we tested whether bee balm (Monarda didyma L.) leaves could have feeding deterrence on fall armyworm. When S. frugipe...

  7. Effect of eastern gamagrass on fall armyworm and corn earworm development

    Science.gov (United States)

    The fall armyworm, Spodoptera frugiperda (J.E. Smith) and the corn earworm, Helicoverpa zea (Boddie) are two important corn pests in the southern U.S. states. Effect of the leaves from the corn relative, the Eastern gamagrass (Tripsacum dactyloides L.) on fall armyworm and corn earworm development ...

  8. Characterization of the earwig, Doru lineare, as a predator of larvae of the fall armyworm, Spodoptera frugiperda: a functional response study.

    Science.gov (United States)

    Sueldo, Mabel Romero; Bruzzone, Octavio A; Virla, Eduardo G

    2010-01-01

    Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) is considered as the most important pest of maize in almost all tropical America. In Argentina, the earwig Doru lineare Eschscholtz (Dermaptera: Forficulidae) has been observed preying on S. frugiperda egg masses in corn crops, but no data about its potential role as a biocontrol agent of this pest have been provided. The predation efficiency of D. lineare on newly emerged S. frugiperda larva was evaluated through a laboratory functional response study. D. lineare showed type II functional response to S. frugiperda larval density, and disc equation estimations of searching efficiency and handling time were (a) = 0.374 and (t) = 182.9 s, respectively. Earwig satiation occurred at 39.4 S. frugiperda larvae.

  9. Biological activities of Solanum pseudocapsicum (Solanaceae) against cotton bollworm, Helicoverpa armigera Hübner and armyworm, Spodoptera litura Fabricius (Lepidotera:Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    Alagarmalai Jeyasankar; Selvaraj Premalatha; Kuppusamy Elumalai

    2012-01-01

    Objective:To evaluate the antifeedant, insecticidal and growth inhibition activities of Solanum pseudocapsicum (S. pseudocapsicum) seed extracts against Spodoptera litura (S. litura) and Helicoverpa armigera (H. armigera). Methods:Hexane, diethyl ether, dichloromethane and ethyl acetate seed extracts were prepared and tested for antifeedant, insecticidal and growth inhibitory activities against fourth instar larvae of S. litura and H. armigera. Results:Ethyl acetate extract showed promising antifeedant and insecticidal activities against S. litura and H. armigera. Percentage of deformed larvae, pupae and adults were maximum in treatment of ethyl acetate extract. Percentage of successful adult emergence was deteriorated by seeds on extract treated larvae. Conclusions: Ethyl acetate extracts of S. pseudocapsicum, showed higher efficiency of antifeedant, insecticidal and growth inhibition activities. Hence, it can be used to controll agricultural insect pests, S. litura and H. armigera.

  10. Eficiência de produtos vegetais no controle da lagarta-do-cartucho-do-milho Spodoptera frugiperda (J.E.Smith, 1797 (Lepidoptera: Noctuidae Efficience of extracts of plantas in control of fall armyworm in corn Spodoptera frugiperda (J.E.Smith, 1797 (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Marcelo Souza Silva Oliveira

    2007-04-01

    Full Text Available O presente trabalho teve por objetivo avaliar a eficiência de produtos vegetais no controle de Spodoptera frugiperda (J.E.Smith, 1797 na cultura do milho. Os experimentos foram instalados, nos anos de 2002 e 2004, com a pulverização dos produtos vegetais em cinco tratamentos, e quatro repetições. No ano de 2002, os produtos testados foram: Azadirachta indica A. Juss. (extrato aquoso 2%, e óleo a 1%; Melia azedarach L. (extrato aquoso 2%; Quassia amara L. (extrato aquoso 2%; óleo de nim, Azadirachta indica 1 e 2%. No ano de 2004, os produtos testados foram: A. indica (extrato aquoso 5%, e óleo a 2%, M. azedarach (extrato aquoso 5%, Trichilia pallida Sw. (extrato aquoso 5%. As avaliações, porcentagem de infestação da lagarta-do-cartucho por parcela, foram efetuadas aos três, sete e dez dias após a pulverização dos extratos. Conclui-se que extratos aquosos das plantas A. indica 2%, T.pallida 5%, Q. amara 2% e M. azedarach 2% e 5% e óleo de A. indica 1% e 2% com adição de tenso ativo não iônico, não possuem eficiência necessária como único método de controle da largarta-do-cartucho S. frugiperda em condições de campo. Os produtos começam a afetar o desenvolvimento da lagarta após alguns dias da ingestão das folhas pulverizadas, observado na avaliação efetuada aos sete dias após a aplicação dos extratos.The objective of this work was to study the efficiency of vegetable pesticides in the control of Spodoptera frugiperda (J.E.Smith, 1797 in corn culture. The experiments were installed, in the years of 2002 and 2004, with the spraying of the vegetable products in five treatments, and four repetitions. In the year of 2002 the tested products were: Azadirachta indica A. Juss (aqueous extract 2%, and oil at 1%; Melia azedarach L. (aqueous extract 2%; Quassia amara L. (aqueous extract 2%; nim oil, Azadirachta indica 1 and 2%. In the year of 2004 the tested products were: A. indica (aqueous extract 5%, and oil at 2%, M

  11. Evidence of multiple/cross resistance to Bt and organophosphate insecticides in Puerto Rico population of the fall armyworm, Spodoptera frugiperda.

    Science.gov (United States)

    Zhu, Yu Cheng; Blanco, Carlos A; Portilla, Maribel; Adamczyk, John; Luttrell, Randall; Huang, Fangneng

    2015-07-01

    Fall armyworm (FAW) is a damaging pest of many economic crops. Long-term use of chemical control prompted resistance development to many insecticide classes. Many populations were found to be significantly less susceptible to major Bt toxins expressed in transgenic crops. In this study, a FAW strain collected from Puerto Rico (PR) with 7717-fold Cry1F-resistance was examined to determine if it had also developed multiple/cross resistance to non-Bt insecticides. Dose response assays showed that the PR strain developed 19-fold resistance to acephate. Besides having a slightly smaller larval body weight and length, PR also evolved a deep (2.8%) molecular divergence in mitochondrial oxidase subunit II. Further examination of enzyme activities in the midgut of PR larvae exhibited substantial decreases of alkaline phosphatase (ALP), aminopeptidase (APN), 1-NA- and 2-NA-specific esterase, trypsin, and chymotrypsin activities, and significant increases of PNPA-specific esterase and glutathione S-transferase (GST) activities. When enzyme preparations from the whole larval body were examined, all three esterase, GST, trypsin, and chymotrypsin activities were significantly elevated in the PR strain, while ALP and APN activities were not significantly different from those of susceptible strain. Data indicated that multiple/cross resistances may have developed in the PR strain to both Bt toxins and conventional insecticides. Consistently reduced ALP provided evidence to support an ALP-mediated Bt resistance mechanism. Esterases and GSTs may be associated with acephate resistance through elevated metabolic detoxification. Further studies are needed to clarify whether and how esterases, GSTs, and other enzymes (such as P450s) are involved in cross resistance development to Bt and other insecticide classes.

  12. Increased long-flight activity triggered in beet armyworm by larval feeding on diet containing Cry1Ac protoxin.

    Directory of Open Access Journals (Sweden)

    Xing Fu Jiang

    Full Text Available Evaluating ecological safety and conducting pest risk analysis for transgenic crops are vitally important before their commercial planting. The beet armyworm, Spodoptera exigua, a long-distance migratory insect pest, is not a direct target of transgenic Cry1Ac-expressing cotton in China, but nevertheless it has recently become an important pest. Migrants leaving their natal field arrive in other appropriate habitat far away in a short time, often followed by larval outbreaks. S. exigua has low susceptibility to Cry1Ac. However, our results from laboratory experiments identified (i sublethal effects of Cry1Ac protoxin on larval development rate, larval and pupal weight, and adult lifetime fecundity, and (ii increased long-flight behavior triggered by Cry1Ac which may contribute to larval outbreaks elsewhere. No significant differences in larval mortality, pupation rate, adult emergence rate, longevity, pre-oviposition period, or oviposition period were observed between controls and larvae fed on artificial diet incorporating a low concentration of Cry1Ac protoxin. The negative sublethal effects on some developmental and reproductive traits and lack of effect on others suggest they do not contribute to the observed severity of S. exigua outbreaks after feeding on Cry1Ac cotton. Interestingly, the percentage of long fliers increased significantly when larvae were reared on diet containing either of two low-dose treatments of Cry1Ac, suggesting a possible increased propensity to disperse long distances triggered by Cry1Ac. We hypothesize that negative effects on development and reproduction caused by Cry1Ac in the diet are offset by increased flight propensity triggered by the poor food conditions, thereby improving the chances of escaping adverse local conditions before oviposition. Increased long-flight propensity in turn may amplify the area damaged by outbreak populations. This phenomenon might be common in other migratory insect pests receiving

  13. 甜菜夜蛾围食膜几丁质结合蛋白SeCBP66在不同体系中的表达%Expression of peritrophic membrane chitin binding protein SeCBP66 of Spodoptera exigua in different systems

    Institute of Scientific and Technical Information of China (English)

    刘彬; 李瑞军; 郭巍; 孙伟明; 赵丹; 单鸣; 徐大庆

    2012-01-01

    分析甜菜夜蛾(Spodoptera exigua)围食膜几丁质结合蛋白SeCBP66氨基酸序列,利用PCR技术扩增获得缺失信号肽编码区围食膜几丁质结合蛋白的基因△(s)-secbp 66.将△(s)-secbp 66克隆到表达载体pET28a和pPIC9K,分别转化大肠杆菌BL21和毕赤酵母GS115进行原核及真核表达;将△(s)-secbp 66克隆到质粒pFastBacTM,转化大肠杆菌DH10Bac构建重组Bacmid,转染昆虫细胞系Sf9及BTI-TN-5B1-4(HighFive)从而在昆虫细胞系中进行表达.结果表明:SeCBP66在原核细胞中未见表达,在酵母细胞中表达产物呈弥散状,而在昆虫细胞系中则能稳定的表达116 kDa的特异蛋白.%Amino acid sequence of chitin-binding protein SeCBP66 of Spodoptera exigua per-itrophic membrane was analyzed and a △(s)-secbp66 encoding SeCBP66 without signal peptide was get by PCR method from the midgut cDNA library of Spodoptera exigua. The △(s)-secbp66 gene was cloned into pET28a and pPIC9K and transformed into E. coli BL21 ,P. pasto-ris GS115 ,resulting recombinant E. coli and P. pastoris,respectively. Using Bac to Bac system, the △(s)secbp66 gene was transfected into insect cell lines Sf9 and BTI-TN-5B1-4 (High-Five). The results showed SeCBP66 was expressed in P. pastoris and insect cell lines, but not in E.coli. However, SeCBP66 appeared as a dispersion of unequal size in P. pastoris while a stable expression was showed as a molecular weight 116 kDa in insect cell lines.

  14. Atividade inseticida do óleo essencial de pimenta longa (Piper hispidinervum C. DC. sobre lagarta-do-cartucho do milho Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae Insecticidal Activity of Long-pepper essential oil (Piper hispidinervum C. DC. on fall armyworm Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Rafaela Karin Lima

    2009-01-01

    Full Text Available Os objetivos desta pesquisa foram a obtenção e caracterização do óleo essencial de folhas de pimenta longa Piper hispidinervum, e avaliação de seu efeito no comportamento e/ou mortalidade da lagarta-do-cartucho do milho Spodoptera frugiperda. O óleo essencial foi obtido pela técnica "arraste a vapor d'água", utilizando-se de um aparelho de Clevenger modificado, e posteriormente submetido, à análise por CG-EM e CG. Foram realizados testes de ingestão e contato tópico em lagartas de 1º e 3º ínstar. Os resultados constataram que o óleo essencial de pimenta-longa possui atividade inseticida sobre S. frugiperda, causando redução alimentar e mortalidade, sendo o safrol (82% seu constituinte majoritário. Verificou-se mortalidade no teste de ingestão em lagartas de 1º ínstar com CL50 = 16,2 mg/mL e para lagartas de 3º ínstar a CL50 = 9,4 mg/mL com redução alimentar CD50 = 0,72 mg/mL; e de toxicidade aguda no teste de contato tópico com DL50 = 277,91 μg/lagarta, após o intervalo de tempo de 96 horas, sendo também observados sintomas de neurotoxicidade, como o efeito knock-down.The objectives of this research were to evaluate the chemical composition and bioactivity of the essential oil from the long-pepper leaves (Piper hispidinervum and its effect on the comportment and/or mortality of the fall armyworm (Spodoptera frugiperda. The essential oil was obtained by steam stream distillation, using the modified Clevenger apparatus, the chemical composition was analyzed by GC-MS and GC. Tests of ingestion and topical application in fall armyworm of 1 st and 3 rd ínstar were made. The results showed that the long-pepper essential oil has insecticide activity on S. frugiperda, causing mortality and food reduction, and safrole (82% as its majority constituent. Mortality was found in the ingestion test in larvae of 1 st ínstar LC50 = 16.2 mg/mL for larvae of 3 rd ínstar LC50 = 9.4 mg/mL, with reduced food CD50 = 0.72 mg/mL; and

  15. Parasitoids attacking fall armyworm (Lepidoptera: Noctuidae) in sweet corn habitats

    Science.gov (United States)

    Fall armyworm larvae, Spodoptera frugiperda (J. E. Smith), were collected from sweet corn plants (Zea mays L.) in fields located in three south Florida counties. Fields were sampled from 2010 – 2015 during the fall and spring seasons. Larvae were brought back to the laboratory to complete developme...

  16. Oviposition choice of two fall armyworm (Lepidoptera: Noctuidae) host strains

    Science.gov (United States)

    Fall armyworm, Spodoptera frugiperda (J. E. Smith), is a noctuid species that is composed of two morphologically identical sympatric host strains (corn and rice) that differ in their distribution among plant hosts. In an effort to explain observations of host fidelity in the field, ovipositional pre...

  17. Use of benzimidazole agar plates to assess fall armyworm (Lepidoptera: Noctuidae) feeding on excised maize and sorghum leaves

    Science.gov (United States)

    The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) is an economically significant pest of sorghum and maize. To screen sorghum and maize germplasm for resistance to fall armyworm feeding, field, greenhouse, or lab bioassays are often utilized individually or in combinatio...

  18. Inferring the annual migration patterns of fall armyworm (Lepidoptera: Noctuidae) in the U.S. from mitochondrial haplotypes.

    Science.gov (United States)

    Spodoptera frugiperda (J.E. Smith) or fall armyworm is an important agricultural pest of a number of crops in the Western Hemisphere. In the U.S., infestations in corn acreages extend from the Mexican to the Canadian border. Because fall armyworm does not survive prolonged ground freezing the infe...

  19. Evaluation of whorl damage by fall armyworm (Lepidoptera:Noctuidae) on field and greenhouse grown sweet sorghum plants

    Science.gov (United States)

    The fall armyworm [Spodoptera frugiperda (Lepidoptera: Noctuidae)] is an economically important pest of sorghum [Sorghum bicolor (L) Moench]. However, resistance to fall armyworm in sweet sorghum has not been extensively studied. A collection of primarily sweet sorghum accessions were evaluated in t...

  20. Caracterização química do óleo essencial de folhas de goiabeira (Psidium guajava L. e seus efeitos no comportamento da lagarta-do-cartucho do milho Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae Essential oil chemical composition from leaves of guava (Psidium guajava L. and its effects on the fall armyworm Spodoptera frugiperda (J. E. Smith, 1797. (Lepidoptera: Noctuidae behavior

    Directory of Open Access Journals (Sweden)

    Rafaela Karin Lima

    2009-01-01

    Full Text Available Nesta pesquisa, objetivou-se a obtenção e caracterização do óleo essencial de folhas da goiabeira Psidium guajava cv. Pedro Sato, e seus possíveis efeitos no comportamento da lagarta-do-cartucho do milho Spodoptera frugiperda. O óleo essencial foi obtido pela técnica "arraste a vapor d'água", utilizando-se de um aparelho de Clevenger modificado e submetido, posteriormente, à análise por cromatografia gasosa acoplada a um espectrômetro de massas CG-EM, a fim de investigar sua composição. Para a avaliação dos efeitos do óleo essencial no comportamento das lagartas de 1º ínstar foram testados quatro tratamentos, dois com o óleo essencial na concentração de 0,01% e 0,001%, diluídos em etanol/água 1:1, e duas testemunhas, uma com água e outra com etanol/água 1:1. Os resultados obtidos mostraram que o óleo essencial de folhas de goiabeira apresenta na sua constituição o α-terpineol (0,9%, 1,8-cineol (7,0%, β-cariofileno (7,2% e o óxido de cariofileno (13,8%. Constatou-se, também, que o óleo essencial demonstrou efeito repelente para a lagarta-do-cartucho na concentração de 0,01%.The aim of this research was to obtain and characterize essential oil from leaves of Psidium guajava cv. Pedro Sato, and its possible effects on fall armyworm Spodoptera frugiperda behavior. The essential oil was obtained through steam distillation, by using a modified Clevenger apparatus, and the chemical composition was later analyzed by gas chromatography coupled to mass spectroscopy GC-MS. In order to evaluate the essential oil effect on the armyworm of 1st instars behavior, four treatments were tested; two with oil at 0.01 and 0.001 % in ethanol/water 1:1 concentration; two controls with water and the other with ethanol/water 1:1. The results showed that the above analyzed essential oil constituted of á-terpineole (0.9%, 1,8-cineole (7.0%, â-caryophyllene (7.2% and the caryophyllene oxide (13.8%. It was also found that the essential

  1. Biology and thermal requirements of Telenomus remus reared on fall armyworm Spodoptera frugiperda eggs Características biológicas e exigências térmicas de Telenomus remus em ovos de Spodoptera frugiperda

    Directory of Open Access Journals (Sweden)

    Regiane Cristina Oliveira de Freitas Bueno

    2008-02-01

    Full Text Available This research aimed at studing Telenomus remus Nixon biology reared on Spodoptera frugiperda (J.E. Smith eggs at different temperatures. Based on the development of the cycle (egg-adult, the thermal requirements and the number of parasitoid generations at constant temperatures were determined. Initially, 24-hour-old S. frugiperda eggs were submitted to parasitism by T. remus during 5 h, being then transferred to acclimatized chambers regulated at 15, 20, 25, 28, 31, and 35°C. The cycle (egg to adult was influenced by temperature varying from 8.3±0.01 to 47.2±0.01 for females and 8.1±0.01 to 46.8±0.01 days for males at 31 and 15°C, respectively. The emergency (% was also influenced by temperature. A reduction in emergency was observed at 15°C and no emergency at 35°C. T. remus sex ratio was not influenced by temperature. Sexual rate was not changed by temperature. Regarding to thermal requirements, thermal constant (K and inferior thermal threshold (Tb were higher for T. remus females (158.88 degree-days and 12.5°C when compared to males (154.12 degree-days and 12.6°C. The estimated number of T. remus generation per year for males and females at laboratory conditions was 5.6 and 5.6, 16.9 and 17.3, 28.3 and 29.0, 35.1 and 36.0, 39.6 and 40.7 at 15, 20, 25, 28, and 31oC, respectively.Este trabalho teve como objetivo estudar a biologia de Telenomus remus Nixon criado em ovos de Spodoptera frugiperda (J.E. Smith em diferentes temperaturas. Com base no desenvolvimento do ciclo (ovo-adulto, foram determinados as exigências térmicas e o número de gerações dos parasitóides em temperaturas constantes. Inicialmente, ovos de S. frugiperda, com 24 horas de idade, foram submetidos ao parasitismo por T. remus, durante cinco horas, sendo então transferidos para câmaras climatizadas reguladas para as temperaturas de 15, 20, 25, 28, 31 e 35°C. A duração do ciclo (ovo-adulto foi influenciada pela temperatura variando de 8,3±0,01 a 47,2±0

  2. The development of a reproducible Agrobacterium tumefaciens transformation system for garlic (Allium sativum L.) and the production of transgenic garlic resistant to beet armyworm (Spodoptera exigua Hübner)

    NARCIS (Netherlands)

    Zheng Sijun, S.J.; Henken, B.; Ahn, Y.K.; Krens, F.A.; Kik, C.

    2004-01-01

    This paper describes the development of a reliable transformation system for garlic (Allium sativum L.) and its application in producing insect resistant GM garlic lines. The transformation system is based on Agrobacterium tumefaciens as a vector, using young callus derived from different callus sou

  3. 甜菜夜蛾田间种群对甲氨基阿维菌素苯甲酸盐和高效氯氰菊酯的代谢抗性机制%Metabolic mechanisms of resistance to emamectin and cypermethrin in field populations of Spodoptera exigua

    Institute of Scientific and Technical Information of China (English)

    侍甜; 车午男; 吴益东; 杨亦桦

    2012-01-01

    甜菜夜蛾Spodoptera exigua(Hübner)云南晋宁、上海奉贤和江苏六合种群对甲氨基阿维菌素苯甲酸盐抗性为45 ~437倍,对高效氯氰菊酯抗性为211~555倍,对其它药剂抗性不明显.这3个田间种群3龄幼虫多功能氧化酶、谷胱甘肽S-转移酶和酯酶的活力分别为室内敏感种群的2.7 ~8.4倍、1.9 ~8.6倍和1.6 ~5.7倍.多功能氧化酶抑制剂PBO和酯酶抑制剂DEF对甲氨基阿维菌素苯甲酸盐的增效比为1.2 ~4.3和1.3~7.7;PBO和DEF对高效氯氰菊酯的增效比为1.8 ~58和3.6 ~ 245;谷胱甘肽JS-转移酶抑制剂DEM对这2种药剂均无增效作用.上述结果表明,解毒代谢增强可能是甜菜夜蛾田间种群对甲氨基阿维菌素苯甲酸盐和高效氯氰菊酯的重要抗性机理,与酯酶和多功能氧化酶活性升高有关,与谷胱甘肽S-转移酶活性升高无关.本文的研究结果还表明,对于代谢抗性机理复杂的多抗性田间种群,根据不同解毒酶抑制剂对药剂的增效作用判断不同解毒代谢酶在抗性形成中的作用更加可靠.%Three populations of Spodoptera exigua (YN-JN, SH-FX, and JS-LH) showed high levels of resistance to emamectin (45 to 437-fold) and cypermethrin (211 to 555-fold) compared to a susceptible SWH strain. Increased activity of detoxification enzymes such as monooxygenases (2. 7 to 8. 4-fold) , glutathione S-transferases (1.9 to 8. 6-fold) and esterases (1. 6 to 5. 7-fold) were detected in these populations compared with the SWH strain. The synergistic ratios (SRs) of the oxidase inhibitor ( PBO) and the esterase inhibitor (DEF) to emamectin were 1.2-4.3 and 1.3-7.7 respectively and the SRs of PBO and DEF to cypermethrin were 1. 8-58 and 3. 6-245 respectively. The glutathione S-transferase inhibitor ( DEM) displayed no significant synergism with these two insecticides. These results indicate that enhanced detoxification by both esterases and oxidases are important resistance mechanisms to

  4. Evaluación de aislamientos de baculovirus para el control de Spodoptera frugiperda (Smith, 1797 (LEP.: NOCTUIDAE, plaga clave del maíz en el noroeste argentino Evaluation of baculovirus strains to control the fall armyworm, Spodoptera frugiperda (Smith, 1797 (LEP.: NOCTUIDAE, a key corn pest in North Western Argentina

    Directory of Open Access Journals (Sweden)

    Marta G. Yasem de Romero

    for Spodoptera frugiperda control, a key pest affecting corn crops in North Western Argentina. These insecticides, however, frequently show low effectiveness. The baculoviruses are a biological alternative to control the fall armyworm. The objective of this research was to assess Nucleopolyhedrovirus native and foreign strains as regards their effectiveness in controlling S. frugiperda. The results showed that S. frugiperda larvae death rate rose with increasing viral concentrations, while viral susceptibility of larvae decreased with insect age. LC50 (lethal concentration for 50% of the tested sample of 7.6 x 10(4 and 4.5 x 10(5 polyhedra/ml for three and five day-old larvae, respectively, were determined for the nuclear polyhedrosis virus (NPV isolated in Leales (Tucumán, Argentina. Similar control levels were determined for the NPV isolated in Oliveros (Santa Fe, Argentina, with lethal viral concentrations (LC50 of 8.6 x 10(4 and 4.0 x 10(5 polyhedra/ml, respectively. The Brazilian isolate was characterized by LC50 levels of 5.9 x 10(5 and 1.5 x 10(6 polyhedral/ml for three-day-old and five-day-old larvae, respectively. The local isolate (VPNSf -Tucumán showed the most lethal effect on the native population of young S. frugiperda (three to five-day-old larvae, with an average lifespan of six days at LC50 levels, while the Oliveros and Brazil isolates showed an average lifespan of seven and nine days, respectively. The VPNSf - Leales isolate was therefore selected as the object of study for this research. Moreover, being a native isolate, it was considered the best alternative from the environmental impact standpoint.

  5. Modeling seasonal migration of fall armyworm moths

    Science.gov (United States)

    Westbrook, J. K.; Nagoshi, R. N.; Meagher, R. L.; Fleischer, S. J.; Jairam, S.

    2016-02-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith), is a highly mobile insect pest of a wide range of host crops. However, this pest of tropical origin cannot survive extended periods of freezing temperature but must migrate northward each spring if it is to re-infest cropping areas in temperate regions. The northward limit of the winter-breeding region for North America extends to southern regions of Texas and Florida, but infestations are regularly reported as far north as Québec and Ontario provinces in Canada by the end of summer. Recent genetic analyses have characterized migratory pathways from these winter-breeding regions, but knowledge is lacking on the atmosphere's role in influencing the timing, distance, and direction of migratory flights. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to simulate migratory flight of fall armyworm moths from distinct winter-breeding source areas. Model simulations identified regions of dominant immigration from the Florida and Texas source areas and overlapping immigrant populations in the Alabama-Georgia and Pennsylvania-Mid-Atlantic regions. This simulated migratory pattern corroborates a previous migratory map based on the distribution of fall armyworm haplotype profiles. We found a significant regression between the simulated first week of moth immigration and first week of moth capture (for locations which captured ≥10 moths), which on average indicated that the model simulated first immigration 2 weeks before first captures in pheromone traps. The results contribute to knowledge of fall armyworm population ecology on a continental scale and will aid in the prediction and interpretation of inter-annual variability of insect migration patterns including those in response to climatic change and adoption rates of transgenic cultivars.

  6. Antibiosis among selected paspalum taxa to the fall armyworm (Lepidoptera: Noctuidae)

    Science.gov (United States)

    Twenty six accessions of the warm-season perennial grass, Paspalum spp., were evaluated for response to the fall armyworm Spodoptera frugiperda (J. E. Smith), an important pest of turfgrass. In growth chamber, excised clipping studies, P. vaginatum 03-539-31 and P. vaginatum 03-525-22 were the most ...

  7. Capture and host strain of fall armyworm males in traps baited with different pheromone blends

    Science.gov (United States)

    Sex pheromone traps baited with four different commercial lures that contained two, three, or four components were used to capture male fall armyworm [Spodoptera frugiperda (J. E. Smith)] in Alabama, Georgia, Florida, and Texas from 2006 – 2009. A subset of the moths collected was analyzed for thei...

  8. Attraction of fall armyworm males (Lepidoptera: Noctuidae) to host strain females

    Science.gov (United States)

    Attraction of wild male fall armyworm, Spodoptera frugiperda (J. E. Smith), was compared in trapping experiments during 2005 – 2009 in Florida. Traps were baited either with a commercial sex pheromone lure or corn and rice strain females obtained from laboratory colonies. Over 7400 male moths were...

  9. Demonstration using field collections that Argentina fall armyworm populations exhibit strain-specific host plant preference

    Science.gov (United States)

    Spodoptera frugiperda, the fall armyworm, is a major economic pest throughout the Western Hemisphere of corn (maize), cotton, sorghum, and a variety of agricultural grasses and vegetable crops. Studies in the United States, the Caribbean, and Brazil demonstrated the existence of two subpopulations ...

  10. Sunn hemp as a ground cover to manage fall armyworm populations

    Science.gov (United States)

    Fall armyworm (FAW), Spodoptera frugiperda, is a serious pest of sweet corn in south Florida and a pest of other vegetable, row, and forage crops in the southeastern, mid-Atlantic, and central U.S. It is a migratory pest, moving north each season from overwintering areas in southern Texas and south...

  11. Screening of Bacillus thuringiensis strains with a strong virulence against Spodoptera exigua larvae%对甜菜夜蛾具有高毒力的Bt菌株筛选

    Institute of Scientific and Technical Information of China (English)

    郭靖; 周子珊; 蔡吉林; 惠识瑶; 张杰; 高继国; 束长龙

    2013-01-01

    依据对夜蛾科具有高毒力cry基因的序列,设计特异性引物对实验室保存的对鳞翅目害虫高效的菌株资源进行筛选.通过比较质粒图谱,对其多样性进行了研究.进一步测定Bt菌株对甜菜夜蛾的杀虫活性,筛选出高毒力的菌株.从192株菌株中筛选出15株对夜蛾科害虫具有高活性的菌株,包含的基因类型有:cry1A、cry1C、cry2A、cry9和vip3A类基因,晶体形态包含:双锥体形、方形、球形;其中2株菌表达130 ku和60 ku的蛋白,1株菌表达130 ku和70 ku的蛋白,其余菌株均表达约130 ku的蛋白;这15株菌通过质粒图谱分析分为8种类型;3株菌对甜菜夜蛾幼虫具有高毒力,其中菌株PS3-C2对甜菜夜蛾LC50为1.87 μg/mL.本研究成功筛选出对甜菜夜蛾具有高毒力的菌株3株,其中PS3-C2菌株与对照菌株KN11活性相当,为新型杀虫基因分离克隆与制剂的研发奠定了基础.%exigua, specific primers were designed for Bt strain selection. After PCR screening, the diversity of selected strains were investigated by comparison with plasmid profiles. Furthermore, strains with high toxicity to S. Exigua were screened by bioassay. Fifteen strains with high activity against S. Exigua were obtained from 192 isolates. These strains contained cry1A, cry1C, cry2A, cry9 and vip3A genes, forming bipyramidal, square or globular crystals. They were classified into eight types according to plasmid profile. One of them expressed both 130 ku and 70 ku proteins, two expressed 130 ku and 60 ku proteins, and three expressed only 130 ku protein. The strain PS3-C2 had the highest activity, with a LC50 of 1.87μg/mL. Three high-toxicity Bt strains against S. Exigua were obtained, and the strain PS3-C2 was a native strain with a comparable activity with the control strain KN11. In conclusion, the present study laid a foundation for Bt pesticides development.

  12. 氯虫苯甲酰胺和氟虫双酰胺对不同虫态甜菜夜蛾的毒力作用%Comparison of the toxicity of chlorantraniliprole and flubendiamide to different developmental stages of Spodoptera exigua

    Institute of Scientific and Technical Information of China (English)

    周超; 王海娜; 李秀环; 王伟; 慕卫

    2011-01-01

    采用浸叶法、点滴法、夹毒叶片法、成虫药膜法、饲喂毒营养液法测定了氯虫苯甲酰胺、氟虫双酰胺对甜菜夜蛾卵、2~4龄幼虫、成虫的活性和对4龄幼虫的拒食活性,以明确氯虫苯甲酰胺和氟虫双酰胺对不同虫态甜菜夜蛾的毒力作用。结果表明,两种杀虫剂均不具有杀卵活性,但可以明显降低初孵幼虫存活率;氯虫苯甲酰胺、氟虫双酰胺均对2龄幼虫活性最高,分别为3龄幼虫的1.50、6.17倍和4龄幼虫的22.25、44.95倍,对4龄幼虫胃毒活性分别为触杀活性的14.10、8.44倍;氯虫苯甲酰胺对甜菜夜蛾成虫毒力为氟虫双酰胺的25.53~34.19倍。氯虫苯甲酰胺、氟虫双酰胺对甜菜夜蛾幼虫表现出较强的拒食作用,至处理后48 h拒食率达到最高,分别为82.73%、84.15%,显著高于对照药剂甲维盐各浓度处理,处理试虫虫体皱缩、体节缩短,体重增加率明显低于对照和甲维盐各处理。%The susceptibilities of eggs, 2nd, 3rd, 4th instar larvae and adults and antifeedant effect of Spodoptera exigua to chlorantraniliprole and flubendiamide were investigated using egg-dip method, leafdip method, topical application, stomach poison test, residual film and fed poison nutrient solution method. The results indicate that there were no ovicidal activities in the two insecticides, but the survival rates of neonate larvae were decreased with the concentration of the two insecticides increased. The toxicity of two insecticides to 2nd instar larvae was the highest, which were 1.50-, 6.17-fold than the 3rd instar lar- vae and 22.25-, 44.95-fold than 4th instar larvae. Two insecticides had good oral toxicity to 4th instar larvae of S. exigua, and were 14.10-, 8.44-fold than the contact toxicity, respectively. The activities of the two insecticides to adults indicated that the chlorantraniliprole was higher than flubendiamide with the toxicity ratios were 25.53 to 34.19-fold. The results of

  13. Penicillin ingestion influences toxic effects of several Cry toxins from Bacillus thuringiensis on Spodoptera exigua larvae%青霉素影响甜菜夜蛾幼虫耐受几种苏云金杆菌晶体蛋白的能力

    Institute of Scientific and Technical Information of China (English)

    陈瑞瑞; 崔金杰; 李国清

    2011-01-01

    本文评估了Cry1Ab、Cry1Ba和Cry1Ca蛋白对甜菜夜蛾2龄幼虫的毒力,其LC50分别为0.442 5、0.675 7μg/cm2和0.150 2 μg/cm2,Cry1Ba毒力最低,其次是Cry1Ab,而Cry1Ca毒力最高.青霉素影响幼虫对晶体毒素的耐受能力;一次添加高剂量(500 μg/ cm2)青霉素于饲料中显著提高幼虫的耐受能力,以含低剂量(60 μg/cm2)青霉素的饲料饲养幼虫多代也能达到相似的效果.%Toxicities of Cry1Ab, Cry1Ba and CrylCa from Bacillus thuringiensis to the 2nd-instar larvae of Spo-doptera exigua were evaluated. The LC50 values were 0. 442 5 μg/cm2, 0. 675 7μg/cm2and 0.150 2 μg/cm2, respectively. Cry1Ba was least toxic, followed by Cry1Ab, and Cry1Ca was most toxic. Penicillin affected larval tolerance to the 3 Cry toxins. At the concentration of 500 μg/cm2, penicillin mixed directly with the toxins could significantly increase larval tolerance. At the concentration of 60 μg/cm2, however, penicillin should be first added alone to the diet for the larvae for several generations to obtain similar tolerance.

  14. Analysis of cry 1Ca gene from Bacillus thuringiensis strains with high insecticidal activity against Spodoptera exigua%对甜菜夜蛾具有杀虫活性的Bt 菌株cry1Ca 基因研究

    Institute of Scientific and Technical Information of China (English)

    王杨; 周子珊; 刘永磊; 韩榕; 张林静; 张杰

    2016-01-01

    One pair of degenerate primers,designed based upon the 14 known sequences of cry 1Ca genes,was used to identify cry 1Ca genes from 472 wild isolates of Bacillus thuringiensis screened in our laboratory,and there were 22 isolates containing cry 1Ca genes.Five patterns of restriction fragment were obtained by the analysis of cry gene diversity depended on PCR-RFLP,indicating that 22 B .thuringiensis isolates could be classified as five types.SDS-PAGE analysis results showed that a main protein band with approximate 130 ku molecular mass was detected in each strain.Western Blotting analysis results also demonstrated that Cry1Ca proteins were expressed normally in all of the 22 strains.The preliminary bioassay was conducted with trypsin-activated Cry proteins ex-tracted from 22 Bt isolates against the neonate larvae of Spodoptera exigua (Hübner).The results showed that all of these strains hade high insecticidal activity against target larvae.The LC50 values of the five selected Bt isolates representing five types against S .exigua were measured,and the results indicated that the toxicity of the five strains was very high;the insecticidal activity of the strains T1-E12 (0.087 μg/g),B16-C8 (0.103 μg/g)and T1-B8 (0.202 μg/g)was similar to that of the positive strain G03 (0.090 μg/g),and these strains have great potential for commercialization.Our findings will lay the foundation for discovery of novel B .thuringiensis isolates.%根据已报道的14个 cry1Ca 基因,设计能够扩增 cry1Ca 全长基因的简并引物。利用该引物对本实验室分离的472株 Bt 菌株进行筛选。PCR 扩增发现22株菌含有 cry1Ca 基因。对22株菌株进行 cry 基因多样性分析,结果获得5种类型酶切图谱,表明这些菌株分为5种类型。SDS-PAGE 结果显示22株菌均表达约130 ku 的蛋白。Western Blotting 结果证实这些株菌中 cry1Ca 基因均正常表达。提取菌株的晶体蛋白,经胰蛋白酶活化,对甜菜夜蛾[Spodoptera

  15. Isolation and DNA barcode characterization of a permanent Telenomus (Hymenoptera: Platygastridae) population in Florida that targets fall armyworm (Lepidoptera: Noctuidae)

    Science.gov (United States)

    Telenomus remus Nixon is a platygastrid egg parasite of the fall armyworm, Spodoptera frugiperda (J. E. Smith), with a history of use as an augmentative biological control agent in Central and South America. Efforts were made in 1975-1977 and again in 1988-1989 to introduce T. remus into the fall ar...

  16. Evaluation of fall armyworm resistance in maize germplasm lines using visual leaf injury rating and predator survey

    Science.gov (United States)

    After examining ear-colonizing pest resistance, 20 maize lines from the USDA-ARS germplasm enhancement of Maize (GEM) Program were evaluated for whorl-feeding fall armyworm (FAW) (Spodoptera frugiperda) resistance using four maize inbred lines as the resistant and susceptible controls. Both FAW inju...

  17. Laboratory evaluations of Lepidopteran-active soybean seed treatments on survivorship of fall armyworm (Lepidoptera:Noctuidae) larvae

    Science.gov (United States)

    Two anthranilic diamide insecticides, chlorantraniliprole and cyantraniliprole, were evaluated as soybean, Glycine max L., seed treatments for control of fall armyworm, Spodoptera frugiperda (J. E. Smith). Bioassays were conducted using 2nd instar larvae and plants from both field and greenhouse gr...

  18. Fall armyworm migration across the Lesser Antilles and the potential for genetic exchanges between North and South American populations

    Science.gov (United States)

    The fall armyworm, Spodoptera frugiperda (J. E. Smith)(Lepidoptera: Noctuidae), is an important agricultural pest of the Western Hemisphere noted for its broad host range, long distance flight capabilities, and a propensity to develop resistance to pesticides that includes a subset of those used in ...

  19. Euplectrus furnius parasitizing Spodoptera frugiperda in maize in Brazil

    Directory of Open Access Journals (Sweden)

    Vinícius Soares Sturza

    2013-11-01

    Full Text Available Brazil is among the world's biggest maize producers and fall armyworm, Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae, is the main insect pest on this crop in the country. Despite the importance of its natural enemies, there still is a lack of information about parasitoids species that attack this insect-pest, such as larval parasitoids. This research reports Euplectrus furnius Walker (Hymenoptera: Eulophidae parasitizing S. fugiperda larvae on maize crop in Brazil.

  20. Using intron sequence comparisons in the triose-phosphate isomerase gene to study the divergence of the fall armyworm host strains

    Science.gov (United States)

    The Noctuid moth, Spodoptera frugiperda (the fall armyworm), is endemic to the Western Hemisphere and appears to be undergoing sympatric speciation to produce two subpopulations that differ in their choice of host plants. The diverging “rice strain” and “corn strain” are morphologically indistinguis...

  1. Comparison of haplotype frequencies differentiate fall armyworm (Lepidoptera: Noctuidae) corn-strain populations from Florida and Brazil.

    Science.gov (United States)

    Nagoshi, Rod N; Silvie, Pierre; Meagher, Robert L

    2007-06-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a major economic pest throughout the Western Hemisphere. Populations can be subdivided into two morphologically identical but genetically distinct strains (corn-strain and rice-strain) that differ in their host plant preferences. These strains can be distinguished by using polymorphisms in the mitochondrial cytochrome oxidase 1 gene. Additional sequence analysis of this locus identified two sites that were highly polymorphic in the corn-strain population and that produced four different haplotype subgroups. Comparisons of the frequency distribution of these haplotypes found no seasonal or plant host specificities, but they did demonstrate that the Brazil corn-strain population is different from corn-strain fall armyworm found in Florida. The development of a rapid means of distinguishing fall armyworm populations originating from Brazil versus Florida provides an opportunity for investigating and comparing the genetic complexity and long-range movements of this important agricultural pest.

  2. Occurrence of entomopathogenic fungi and parasitic nematodes on Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae collected in Central Chiapas, Mexico

    Science.gov (United States)

    Fall armyworm larvae (FAW), Spodoptera frugiperda (J. E. Smith) were collected from whorl-stage cornfields, between the V2 and V4 stages, in 22 localities of Central, Chiapas, México, called "La Frailesca" during late June 2009 to determine the occurrence of native entomopathogens and parasitic nema...

  3. Lyophilization of Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae yields high-quality DNA for use in AFLP genetic studies

    Science.gov (United States)

    Agricultural research in the 21st century has become a collaborative effort. Research on crop pests like Spodoptera frugiperda (J.E. Smith), commonly known as the fall armyworm (FAW), can involve international collaboration because it is a pest not only in the southern United States, but also in La...

  4. Comparison of haplotype frequencies differentiate fall armyworm (Lepidoptera : Noctuidae) corn-strain populations from Florida and Brazil

    OpenAIRE

    Nagoshi, R. N.; Silvie, Pierre; Meagher, R.L.

    2007-01-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a major economic pest throughout the Western Hemisphere. Populations can be subdivided into two morphologically identical but genetically distinct strains (corn-strain and rice-strain) that differ in their host plant preferences. These strains can be distinguished by using polymorphisms in the mitochondrial cytochrome oxidase I gene. Additional sequence analysis of this locus identified two sites that were highly p...

  5. Molecular Phylogeny of Indonesian Armyworm Mythimna Guenée (Lepidoptera: Noctuidae: Hadeninae Based on CO I Gene Sequences

    Directory of Open Access Journals (Sweden)

    HARI SUTRISNO

    2012-06-01

    Full Text Available Armyworm Mythimna Guenée is one of the most important pests on graminaceous crops and pastures in South East Asia (i.e. M. separata Walker is well known to cause serious damages on rice in Indonesia. Like of most other genera of moths, the systematic of this genus is still in dispute, especially on the taxonomy and classification within this genus due to their morphological characters that are very difficult to distinguish from one to others. Molecular approaches such as using CO I gene sequence to differentiate among species has beenrecommended since this gene has ability to reveal the character identity at the specific level. In order to populate the genetic characters of Indonesian Mythimna, to clarify the clasification within the genus Mythimna and to reveal the phylogenetic relationship among them, we analyzed 14 species of Mythimna and two species outgroups (Spodoptera litura dan S. exigua based on nucleotide sequence variation across a 649 bp region in the CO I gene. Over entire 649 bp region 72% of the nucleotide positions were constant, 10.6% were uninformtive (i.e. any variants were found in a single sequence and 16.9% were parsimony informative. The informative site constituted in the 3rd codon position was the highest, whereas in 2nd codon position was the lowest. The results also showed that the base composition of this region was low A + T biased. The results showed that the monophyly of Mytimna was supported by 95% bootstrap test at any tree building methods. The three subgenera based on morphology were recovered but M. (Mythimna shown to be a paraphyletic group in term of M. (Hyphilare, and M. (Pseudalteia; M. (Mythimna was branched off first then followed by M. (Pseudaletia and M. (Hyphilare. However, all internal nodes were least support except for the monophyly of subgenus M. (Hyphilare. It indicates that the relationships among internal nodes proposed here were least valid due to the number of species included in the

  6. Susceptibility of field populations of the fall armyworm (Lepidoptera: Noctuidae) from Florida and Puerto Rico to purified Cry1F protein and corn leaf tissue containing single and pyramided Bt genes

    Science.gov (United States)

    Larval survival of Cry1F-susceptible (FL), -resistant (PR and Cry1F-RR), and -heterozygous (FL x PR and Cry1F-RS) populations of the fall armyworm, Spodoptera frugiperda (J.E. Smith) to purified Cry1F protein and corn leaf tissue of seven Bacillus thuringiensis (Bt) corn hybrids and five non-Bt corn...

  7. Diallel crossing among maize populations for resistance to fall armyworm

    Directory of Open Access Journals (Sweden)

    Alvarez María del Pilar

    2002-01-01

    Full Text Available Among the insects infecting the maize (Zea mays L. crop in Brazil, the fall armyworm (Spodoptera frugiperda Smith, 1797, Lepdoptera: Noctuidae is considered one of the most important because it causes the highest damage to yield. Genetic resistance to the fall armyworm has be an effective control strategy. The main objective of this work was to evaluate new germplasm sources for resistance to the fall armyworm, the key pest for the maize crop in Brazil. A partial diallel design between 20 varieties of Brazilian germplasm and nine exotic and semi-exotic varieties of different origin was used. The 180 crosses and 29 parental varieties along with two commercial checks were evaluated in three locations in the State of São Paulo State (Brasil. Fall armyworm resistance (FAWR under artificial and natural infestations, grain yield (GY, and plant height (PH were analyzed. The populations CMS14C and MIRT, and hybrid São José x MIRT showed the highest resistance, with values of 1.8, 1.7 and 1.4, respectively. Populations PMI9401 and PR91B, and the hybrid CMS14C x (B97xITU had best yields, with 4893, 3858 and 5677 kg ha-1, respectively. Heterosis ranged from -28% to 47% for FAWR and from -21% to 125% for GY, with mean values of -0,43% and 31%, respectively. Genotype by environment interaction was not significant for FAWR. The effects of varieties and heterosis were significant for all traits, showing that both additive and dominance effects may be important as sources of variation. For FAWR, only specific heterosis presented significance, suggesting strong genetic divergence between specific pairs of parental populations. Brasilian populations PMI9302 and São José, and the exotic population PR91B presented high performance per se, and also in croses for FAWR and GY. Crosses PMI9401 x (Cuba110 x EsalqPB1 and São José x MIRT presented high specific heterosis effects for both characters. These populations can be useful to be introgressed in maize

  8. F2 screen for resistance to Bacillus thuringiensis Cry2Ab2-maize in field populations of Spodoptera frugiperda (Lepidoptera: Noctuidae) from the southern United States

    Science.gov (United States)

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a target of transgenic maize and cotton expressing Bacillus thuringiensis (Bt) proteins in both North and South America. In 2013 and 2014, a total of 215 F2 two-parent families of S. frugiperda were established usin...

  9. Changes in midgut endopeptidase activity of Spodoptera frugiperda (Lepidoptera: Noctuidae) are responsible for adaptation to soybean proteinase inhibitors.

    Science.gov (United States)

    Paulillo, L C; Lopes, A R; Cristofoletti, P T; Parra, J R; Terra, W R; Silva-Filho, M C

    2000-06-01

    The development of transgenic maize plants expressing soybean proteinase inhibitors could reduce the economic damage of one of the major maize pests in Brazil, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797). We examined the influence of soybean proteinase inhibitors on digestive enzyme properties and development of S. frugiperda larvae. The inhibition of trypsin and chymotrypsin activities in vitro by soybean proteinase inhibitors suggested that either Kunitz (SBTI) or Bowman-Birk (SBBI) would have a potential antimetabolic effect when ingested by insect larvae. However, chronic ingestion of semipurified soybean inhibitors did not result in a significant reduction of growth and development of fall armyworm. Therefore, digestive serine proteinase activities (trypsin and chymotrypsin) of fall armyworm larvae were characterized. The results suggest that S. frugiperda was able to physiologically adapt to dietary proteinase inhibitors by altering the complement of proteolytic enzymes in the insect midguts.

  10. Estimation of resistance allele frequency to maize incorporated Bacillus thuringiensis Cry2Ab2 protein in field populations of the fall army Spodoptera frugiperda (Lepidoptera: Noctuidae) from south region of the United State

    Science.gov (United States)

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a target of transgenic maize and cotton expressing Bacillus thuringiensis (Bt) proteins in both North and South Americas. In the falls of 2013 and 2014, a total of 215 F2 two-parent families of S. frugiperda were es...

  11. Vip3A, a novel Bacillus thuringiensis vegetative insecticidal protein with a wide spectrum of activities against lepidopteran insects.

    OpenAIRE

    Estruch, J J; Warren, G W; Mullins, M A; Nye, G J; Craig, J. A.; Koziel, M G

    1996-01-01

    A novel vegetative insecticidal gene, vip3A(a), whose gene product shows activity against lepidopteran insect larvae including black cutworm (Agrotis ipsilon), fall armyworm (Spodoptera frugiperda), beet armyworm (Spodoptera exigua), tobacco budworm (Heliothis virescens), and corn earworm (Helicoverpa zea) has been isolated from Bacillus thuringiensis strain AB88. VIP3-insecticidal gene homologues have been detected in approximately 15% of Bacillus strains analyzed. The sequence of the vip3A(...

  12. Predatory potential of Geocoris spp. and Orius insidiosus on fall armyworm in resistant and susceptible turf.

    Science.gov (United States)

    Joseph, S V; Braman, S K

    2009-06-01

    Predatory potential and performance of the predaceous heteropterans, Geocoris punctipes (Say), G. uliginosus (Say) (Geocoridae), and Orius insidiosus (Say) (Anthocoridae), were evaluated using fall armyworm, Spodoptera frugiperda (J. E. Smith), as prey on different turfgrass taxa (resistant zoysiagrasses, 'Cavalier' and 'Palisades'; moderately resistant Bermuda grass, 'TifSport'; and susceptible seashore paspalum, 'Sea Isle 1') through laboratory and field studies. When background mortality was taken into account, in small arena trials in the laboratory, the greatest mortality by predators occurred on TifSport. The predator impact on TifSport by O. insidiosus was 92.6% above the mortality in the no-predator treatment on that grass. Predator induced mortality was rarely significant on the highly resistant zoysiagrass cultivar Cavalier because mortality, even in the absence of predators, was so high. Survival of larvae on TifSport Bermuda grass was significantly reduced by the addition of just two O. insidiosus per pot in laboratory pot trials. An increase in predator density to 4, 6, 8, or 10 further suppressed larval survival. O. insidiosus reduced larval survival on Sea Isle 1 at all densities. On Sea Isle 1, a density of two O. insidiosus resulted in > 50% reduction in live fall armyworms compared with the no predator treatment in laboratory trials. However, addition of O. insidiosus did not significantly reduce survival of fall armyworm larvae on this cultivar in the field in the presence of alternative prey and predators. O. insidiosus densities of six or higher per 181.4 cm2 did significantly reduce larval survival on TifSport Bermuda grass by as much as 80% during a 5-d trial period in the field. Predator-induced mortality among all trials was most consistent on a grass of intermediate resistance, TifSport Bermuda grass.

  13. Mortality Dynamics of Spodoptera frugiperda (Lepidoptera: Noctuidae) Immatures in Maize

    Science.gov (United States)

    Varella, Andrea Corrêa; Menezes-Netto, Alexandre Carlos; Alonso, Juliana Duarte de Souza; Caixeta, Daniel Ferreira; Peterson, Robert K. D.; Fernandes, Odair Aparecido

    2015-01-01

    We characterized the dynamics of mortality factors affecting immature developmental stages of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Multiple decrement life tables for egg and early larval stages of S. frugiperda in maize (Zea mays L.) fields were developed with and without augmentative releases of Telenomus remus Nixon (Hymenoptera: Platygastridae) from 2009 to 2011. Total egg mortality ranged from 73 to 81% and the greatest egg mortality was due to inviability, dislodgement, and predation. Parasitoids did not cause significant mortality in egg or early larval stages and the releases of T. remus did not increase egg mortality. Greater than 95% of early larvae died from predation, drowning, and dislodgment by rainfall. Total mortality due to these factors was largely irreplaceable. Results indicate that a greater effect in reducing generational survival may be achieved by adding mortality to the early larval stage of S. frugiperda. PMID:26098422

  14. Mortality Dynamics of Spodoptera frugiperda (Lepidoptera: Noctuidae) Immatures in Maize.

    Science.gov (United States)

    Varella, Andrea Corrêa; Menezes-Netto, Alexandre Carlos; Alonso, Juliana Duarte de Souza; Caixeta, Daniel Ferreira; Peterson, Robert K D; Fernandes, Odair Aparecido

    2015-01-01

    We characterized the dynamics of mortality factors affecting immature developmental stages of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae). Multiple decrement life tables for egg and early larval stages of S. frugiperda in maize (Zea mays L.) fields were developed with and without augmentative releases of Telenomus remus Nixon (Hymenoptera: Platygastridae) from 2009 to 2011. Total egg mortality ranged from 73 to 81% and the greatest egg mortality was due to inviability, dislodgement, and predation. Parasitoids did not cause significant mortality in egg or early larval stages and the releases of T. remus did not increase egg mortality. Greater than 95% of early larvae died from predation, drowning, and dislodgment by rainfall. Total mortality due to these factors was largely irreplaceable. Results indicate that a greater effect in reducing generational survival may be achieved by adding mortality to the early larval stage of S. frugiperda.

  15. New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory

    Directory of Open Access Journals (Sweden)

    Cherre Sade Bezerra Da Silva

    2013-09-01

    Full Text Available New method for rearing Spodoptera frugiperda in laboratory shows that larval cannibalism is not obligatory. Here we show, for the first time, that larvae of the fall armyworm (FAW, Spodoptera frugiperda (Lepidoptera, Noctuidae, can be successfully reared in a cohort-based manner with virtually no cannibalism. FAW larvae were reared since the second instar to pupation in rectangular plastic containers containing 40 individuals with a surprisingly ca. 90% larval survivorship. Adult females from the cohort-based method showed fecundity similar to that already reported on literature for larvae reared individually, and fertility higher than 99%, with the advantage of combining economy of time, space and material resources. These findings suggest that the factors affecting cannibalism of FAW larvae in laboratory rearings need to be reevaluated, whilst the new technique also show potential to increase the efficiency of both small and mass FAW rearings.

  16. Atividade de extrato aquoso de folhas de nim (Azadirachta indica sobre Spodoptera frugiperda Activity of neem tree (Azadirachta indica leaves aqueous extract on Spodoptera frugiperda

    Directory of Open Access Journals (Sweden)

    Hélio Teixeira Prates

    2003-03-01

    Full Text Available A lagarta-do-cartucho do milho (Spodoptera frugiperda (J. E. Smith tem sido controlada com inseticidas sintéticos. Uma das caracteristicas do nim (Azadirachta indica A. Juss é sua atividade inseticida contra pragas, como sucedâneo aos sintéticos. O objetivo deste trabalho foi avaliar a atividade inseticida do extrato aquoso das folhas do nim sobre a lagarta-do-cartucho do milho, em laboratório. Bioensaios com diferentes concentrações de extrato em dieta artificial, tendo o inseticida chlorpyrifos como testemunha, revelaram, 15 dias após infestação com larvas, eficiência equivalente entre as concen- trações 3,60 a 10,00 mg mL-1. A análise de Probit mostrou CL50 = 2,67 mg mL-1; o extrato aquoso das folhas de nim apresenta, portanto, efeito inseticida sobre a lagarta-do-cartucho do milho.The fall armyworm (Spodoptera frugiperda (J. E. Smith has been controlled with synthetic insecticides bringing risk to the environment. Neem (Azadirachta indica A. Juss is reported to be a natural alternative to synthetic insecticides against many insect species. The objective of this work was to evaluate the activity of neem leaves aqueous extract on fall armyworm, in laboratory. Bioassays carried out using artificial feed with various extract concentrations, and chlorpyrifos as control, indicated, 15 days after larvae infestation, similar efficiency in concentrations from 3.60 to 10.00 mg mL-1. Probit analysis showed LC50 = 2.67 mg mL-1. Hence, aqueous extract from neem leaves are active against fall armyworm.

  17. Interspecific interaction between Telenomus remus (Hymenoptera: Platygastridae) and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae) on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs.

    Science.gov (United States)

    Carneiro, Tatiana R; Fernandes, Odair A

    2012-12-01

    This work aims to evaluate the interspecific interaction between Trichogramma pretiosum and Telenomus remus, two biological control agents of fall armyworm (Spodoptera frugiperda) eggs. Eggs of Spodoptera frugiperda previously parasitized by Telenomus remus were offered to Trichogramma pretiosum, and those parasitized by Trichogramma pretiosum were offered to Telenomus remus. The previously parasitized eggs were tested at different embryonic development stages for each parasitoid. In addition, to evaluate the competition between species, Spodoptera frugiperda eggs were offered to the parasitoids simultaneously. The behavior of the insects was recorded under a stereomicroscope. When Spodoptera frugiperda eggs were previously exposed to either parasitoid, there was no emergence of the other parasitoid. When the Telenomus remus and Trichogramma pretiosum females were placed together with Spodoptera frugiperda eggs, Telenomus remus had a greater parasitism rate. Except searching time, all Trichogramma pretiosum behaviors took a longer time than Telenomus remus behaviors. Thus, despite belonging to different families, each of these parasitoids is able to recognize host eggs previously parasitized by the other. So, this suggests that the recognition mechanism involved is not exclusively specific.

  18. The occurrence and pathogenicity of Phoma exigua Desm. var. exigua for selected species of herbs

    Directory of Open Access Journals (Sweden)

    Zofia Machowicz-Stefaniak

    2012-12-01

    Full Text Available P. exigua var. exigua was isolated from underground and aboveground organs of different herb plant species in the years 1998-2006. Pathogenicity tests of three randomly chosen isolates of the fungus T 299, T 261 and T 277 for thyme and of three isolates M 1657, M 1193 and M 1635 for lemon balm were carried out. The effect of water suspension of fungus spores on the germination ability of schizocarps and of infected soil on sprouting and seedling health was studied. The study of microscopic structures of the fungus developing on plants, isolation of the fungus on artificial media and macro- and microscopic analysis on standard media are essential for the correct identification of P. exigua var. exigua. The polyphagous nature of the fungus is confirmed by the obtained results. The tested isolates were found to be occasional pathogens of thyme and lemon balm in the studied conditions. The harmfulness of the tested isolates pointed to inhibition of schizocarp germination, sprouting of plants and the ability to cause necrosis of germs, roots and epicotyl.

  19. Effects of Piper hispidinervum on spermatogenesis and histochemistry of ovarioles of Spodoptera frugiperda.

    Science.gov (United States)

    Alves, T J S; Cruz, G S; Wanderley-Teixeira, V; Teixeira, A A C; Oliveira, J V; Correia, A A; Câmara, C A G; Cunha, F M

    2014-05-01

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), not only damages crops, but controlling its population also requires synthetic insecticides, which leads to selection of resistant populations and environmental contamination. Essential oils are an alternative for controlling this insect. There are few studies of the effects of these oils on the insect's reproductive system. We evaluated the effects of the long pepper, Piper hispidinervum, essential oil on the gonads of the armyworm and tested its possible influence on the fertility of this insect. Dosages of 30 and 50 mg/ml were tested in 3(rd) instar caterpillars using the leaf immersion method. Testes and ovarioles were collected, fixed with 10% formalin and embedded in Historesin. The sections were stained with toluidine blue and Mallory trichrome to detect connective tissue, periodic acid-Schiff to detect neutral carbohydrates, and bromophenol blue to detect proteins. We found that the long pepper essential oil affected negatively the spermatogenesis and altered the histochemistry of the ovarioles of S. frugiperda. The effects of long pepper oil suggest that it is a promising tool for controlling the armyworm pest.

  20. Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize.

    Science.gov (United States)

    Sousa, Fernanda F; Mendes, Simone M; Santos-Amaya, Oscar F; Araújo, Octávio G; Oliveira, Eugenio E; Pereira, Eliseu J G

    2016-01-01

    Exposure to Bacillus thuringiensis (Bt) toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50-70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in these populations

  1. Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize

    Science.gov (United States)

    Sousa, Fernanda F.; Mendes, Simone M.; Santos-Amaya, Oscar F.; Araújo, Octávio G.; Oliveira, Eugenio E.

    2016-01-01

    Exposure to Bacillus thuringiensis (Bt) toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50–70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in these populations

  2. Life-History Traits of Spodoptera frugiperda Populations Exposed to Low-Dose Bt Maize.

    Directory of Open Access Journals (Sweden)

    Fernanda F Sousa

    Full Text Available Exposure to Bacillus thuringiensis (Bt toxins in low- and moderate-dose transgenic crops may induce sublethal effects and increase the rate of Bt resistance evolution, potentially compromising control efficacy against target pests. We tested this hypothesis using the fall armyworm Spodoptera frugiperda, a major polyphagous lepidopteran pest relatively tolerant to Bt notorious for evolving field-relevant resistance to single-gene Bt maize. Late-instar larvae were collected from Bt Cry1Ab and non-Bt maize fields in five locations in Brazil, and their offspring was compared for survival, development, and population growth in rearing environment without and with Cry1Ab throughout larval development. Larval survival on Cry1Ab maize leaves varied from 20 to 80% among the populations. Larvae reared on Cry1Ab maize had seven-day delay in development time in relation to control larvae, and such delay was shorter in offspring of armyworms from Cry1Ab maize. Population growth rates were 50-70% lower for insects continuously exposed to Cry1Ab maize relative to controls, showing the population-level effect of Cry1Ab, which varied among the populations and prior exposure to Cry1Ab maize in the field. In three out of five populations, armyworms derived from Bt maize reared on Cry1Ab maize showed higher larval weight, faster larval development and better reproductive performance than the armyworms derived from non-Bt maize, and one of these populations showed better performance on both Cry1Ab and control diets, indicating no fitness cost of the resistance trait. Altogether, these results indicate that offspring of armyworms that developed on field-grown, single-gene Bt Cry1Ab maize had reduced performance on Cry1Ab maize foliage in two populations studied, but in other three populations, these offspring had better overall performance on the Bt maize foliage than that of the armyworms from non-Bt maize fields, possibly because of Cry1Ab resistance alleles in

  3. Development and validation of real-time PCR tests for the identification of four Spodoptera species: Spodoptera eridania, Spodoptera frugiperda, Spodoptera littoralis, and Spodoptera litura (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Van de Vossenberg, B T L H; Van der Straten, M J

    2014-08-01

    The genus Spodoptera comprises 31 species, 4 of which are listed as quarantine pests for the European Union: Spodoptera eridania (Cramer), Spodoptera frugiperda (Smith), Spodoptera littoralis (Boisduval), and Spodoptera litura (F.). In international trade, the earlier life stages (eggs and larvae) are being intercepted at point of inspection most frequently, challenging the possibilities of morphological identification. To realize a rapid and reliable identification for all stages, we developed and validated four simplex real-time polymerase chain reaction identification tests based on the mitochondrial cytochrome b gene using dual-labeled hydrolysis probes. Method validation on dilutions of extracted DNA of the target organisms showed that low levels of template (up to 0.2-100 pg) can reliably be identified. No cross-reactivity was observed with 14 nontarget Spodoptera and 5 non-Spodoptera species in the specific Spodoptera tests. The tests showed to be repeatable, reproducible (both 100%), and robust. The new Spodoptera tests have proven to be suitable tools for routine identification of all life stages of S. eridania, S. frugiperda, S. littoralis, and S. litura.

  4. Fall armyworm migration across the Lesser Antilles and the potential for genetic exchanges between North and South American populations

    Science.gov (United States)

    Nagoshi, Rodney N.; Hay-Roe, Mirian; Khan, Ayub; Murúa, M. Gabriela; Silvie, Pierre; Vergara, Clorinda; Westbrook, John

    2017-01-01

    The fall armyworm, Spodoptera frugiperda (J. E. Smith)(Lepidoptera: Noctuidae), is an important agricultural pest of the Western Hemisphere noted for its broad host range, long distance flight capabilities, and a propensity to develop resistance to pesticides that includes a subset of those used in genetically modified corn varieties. These characteristics exacerbate the threat fall armyworm poses to agriculture, with the potential that a resistance trait arising in one geographical location could rapidly disseminate throughout the hemisphere. A region of particular concern is the Caribbean, where a line of islands that extends from Florida to Venezuela provides a potential migratory pathway between populations from North and South America that could allow for consistent and substantial genetic interactions. In this study, surveys of populations from Peru, Bolivia, Paraguay, and Trinidad & Tobago expand on previous work in South America that indicates a generally homogeneous population with respect to haplotype markers. This population differs from that found in most of the Lesser Antilles where a combination of genetic and meteorological observations is described that indicate fall armyworm migration from Puerto Rico to as far south as Barbados, but does not support significant incursion into Trinidad & Tobago and South America. Air transport projections demonstrate that the wind patterns in the Caribbean region are not conducive to consistent flight along the north-south orientation of the Lesser Antilles, supporting the conclusion that such migration is minor and sporadic, providing few opportunities for genetic exchanges. The implications of these findings on the dissemination of deleterious traits between the two Western Hemisphere continents are discussed. PMID:28166292

  5. Turnabout Is Fair Play: Herbivory-Induced Plant Chitinases Excreted in Fall Armyworm Frass Suppress Herbivore Defenses in Maize.

    Science.gov (United States)

    Ray, Swayamjit; Alves, Patrick C M S; Ahmad, Imtiaz; Gaffoor, Iffa; Acevedo, Flor E; Peiffer, Michelle; Jin, Shan; Han, Yang; Shakeel, Samina; Felton, Gary W; Luthe, Dawn S

    2016-05-01

    The perception of herbivory by plants is known to be triggered by the deposition of insect-derived factors such as saliva and oral secretions, oviposition materials, and even feces. Such insect-derived materials harbor chemical cues that may elicit herbivore and/or pathogen-induced defenses in plants. Several insect-derived molecules that trigger herbivore-induced defenses in plants are known; however, insect-derived molecules suppressing them are largely unknown. In this study, we identified two plant chitinases from fall armyworm (Spodoptera frugiperda) larval frass that suppress herbivore defenses while simultaneously inducing pathogen defenses in maize (Zea mays). Fall armyworm larvae feed in enclosed whorls of maize plants, where frass accumulates over extended periods of time in close proximity to damaged leaf tissue. Our study shows that maize chitinases, Pr4 and Endochitinase A, are induced during herbivory and subsequently deposited on the host with the feces. These plant chitinases mediate the suppression of herbivore-induced defenses, thereby increasing the performance of the insect on the host. Pr4 and Endochitinase A also trigger the antagonistic pathogen defense pathway in maize and suppress fungal pathogen growth on maize leaves. Frass-induced suppression of herbivore defenses by deposition of the plant-derived chitinases Pr4 and Endochitinase A is a unique way an insect can co-opt the plant's defense proteins for its own benefit. It is also a phenomenon unlike the induction of herbivore defenses by insect oral secretions in most host-herbivore systems.

  6. Interspecific interaction between Telenomus remus (Hymenoptera: Platygastridae and Trichogramma pretiosum (Hymenoptera: Trichogrammatidae on Spodoptera frugiperda (Lepidoptera: Noctuidae eggs

    Directory of Open Access Journals (Sweden)

    Tatiana R. Carneiro

    2012-12-01

    Full Text Available This work aimes to evaluate the interspecific interaction between Trichogramma pretiosum and Telenomus remus, two biological control agents of fall armyworm (Spodoptera frugiperda eggs. Eggs of Spodoptera frugiperda previously parasitized by Telenomus remus were offered to Trichogramma pretiosum, and those parasitized by Trichogramma pretiosum were offered to Telenomus remus. The previously parasitized eggs were tested at different embryonic development stages for each parasitoid. In addition, to evaluate the competition between species, Spodoptera frugiperda eggs were offered to the parasitoids simultaneously. The behavior of the insects was recorded under a stereomicroscope. When Spodoptera frugiperda eggs were previously exposed to either parasitoid, there was no emergence of the other parasitoid. When the Telenomus remus and Trichogramma pretiosum females were placed together with Spodoptera frugiperda eggs, Telenomus remus had a greater parasitism rate. Except searching time, all Trichogramma pretiosum behaviors took a longer time than Telenomus remus behaviors. Thus, despite belonging to different families, each of these parasitoids is able to recognize host eggs previously parasitized by the other. So, this suggests that the recognition mechanism involved is not exclusively specific.Este trabalho objetiva avaliar a interação interesespecífica entre Trichogramma pretiosum e Telenomus remus, dois agentes de controle biológico de ovos de Spodoptera frugiperda. Posturas de Spodoptera frugiperda previamente parasitadas por Telenomus remus foram ofertadas a Trichogramma pretiosum e aquelas parasitadas por Trichogramma pretiosum foram ofertadas a Telenomus remus. As posturas previamente parasitadas foram testadas em diferentes estágios de desenvolvimento embrionário para cada parasitoide. Ainda para verificar a competição entre as espécies, posturas de Spodoptera frugiperda foram ofertadas aos parasitoides simultaneamente. O

  7. Characterization of the Spodoptera exigua baculovirus genome: structural and functional analysis of a 20 KB fragment.

    NARCIS (Netherlands)

    Strien, van E.A.

    1997-01-01

    Baculoviruses are attractive, biological alternatives to chemical control agents of insect pests. These viruses are natural agents influencing the size insect populations. They are often species- specific and some of them are highly efficacious, though their speed of action cannot meet that of chemi

  8. Proteolytic processing of Bacillus thuringiensis Vip3A proteins by two Spodoptera species.

    Science.gov (United States)

    Caccia, Silvia; Chakroun, Maissa; Vinokurov, Konstantin; Ferré, Juan

    2014-08-01

    Vip3 proteins have been described to be secreted by Bacillus thuringiensis during the vegetative growth phase and to display a broad insecticidal spectrum against lepidopteran larvae. Vip3Aa protoxin has been reported to be significantly more toxic to Spodoptera frugiperda than to Spodoptera exigua and differences in the midgut processing have been proposed to be responsible. In contrast, we have found that Vip3Ae is essentially equally toxic against these two species. Proteolysis experiments were performed to study the stability of Vip3A proteins to peptidase digestion and to see whether the differences found could explain differences in toxicity against these two Spodoptera species. It was found that activation of the protoxin form and degradation of the 62kDa band took place at lower concentrations of trypsin when using Vip3Aa than when using Vip3Ae. The opposite effect was observed for chymotrypsin. Vip3Aa and Vip3Ae protoxins were effectively processed by midgut content extracts from the two Spodoptera species and the proteolytic activation did not produce a peptidase resistant core under these in vitro conditions. Digestion experiments performed with S. frugiperda chromatography-purified digestive serine peptidases showed that the degradation of the Vip3A toxins active core is mainly due to the action of cationic chymotrypsin-like peptidase. Although the digestion patterns of Vip3A proteins do not always correlate with toxicity, the peptidase stability of the 62kDa core is in agreement with intraspecific differences of toxicity of the Vip3Aa protein.

  9. Performance and cross-crop resistance of Cry1F-maize selected Spodoptera frugiperda on transgenic Bt cotton: implications for resistance management

    OpenAIRE

    Fei Yang; Kerns, David L.; Sebe Brown; Ryan Kurtz; Tim Dennehy; Bo Braxton; Graham Head; Fangneng Huang

    2016-01-01

    Transgenic crops producing Bacillus thuringiensis (Bt) proteins have become a primary tool in pest management. Due to the intensive use of Bt crops, resistance of the fall armyworm, Spodoptera frugiperda, to Cry1F maize has occurred in Puerto Rico, Brazil, and some areas of the southeastern U.S. The sustainability of Bt crops faces a great challenge because the Cry1F-maize resistant S. frugiperda may also infest other Bt crops in multiple cropping ecosystems. Here we examined the survival and...

  10. In vitro metabolism of a linear furanocoumarin (8-methoxypsoralen, xanthotoxin) by mixed-function oxidases of larvae of black swallowtail butterfly and fall armyworm

    Energy Technology Data Exchange (ETDEWEB)

    Bull, D.L.

    1986-04-01

    Studies were made of the comparative in vitro metabolism of (/sup 14/C)xanthotoxin and(/sup 14/C)aldrin by homogenate preparations of midguts and bodies (carcass minus digestive tract and head) of last-stage larvae of the black swallowtail butterfly (Papilio polyxenes Fabr.) and the fall armyworm (Spodoptera frugiperda (J. E. Smith)). The two substrates were metabolized by 10,000g supernatant microsomal preparations from both species. Evidence gained through the use of a specific inhibitor and cofactor indicated that mixed-function microsomal oxidases were major factors in the metabolism and that the specific activity of this enzyme system was considerably higher in midgut preparations from P. polyxenes than in similar preparations from S. frugiperda. Aldrin was metabolized 3-4 times faster by P. polyxenes, and xanthotoxin 6-6.5 times faster.

  11. Insecticidal Activity and Histopathological Effects of Vip3Aa Protein from Bacillus thuringiensis on Spodoptera litura.

    Science.gov (United States)

    Song, Feifei; Lin, Yunfeng; Chen, Chen; Shao, Ensi; Guan, Xiong; Huang, Zhipeng

    2016-10-28

    Vegetative insecticidal proteins (Vips) are insecticidal proteins synthesized by Bacillus thuringiensis during the vegetative stage of growth. In this study, Vip3Aa protein, obtained by in vitro expression of the vip3Aa gene from B. thuringiensis WB5, displayed high insecticidal activity against Spodoptera litura aside from Spodoptera exigua and Helicoverpa armigera. Bioassay results showed that the toxicity of Vip3Aa protein against S. litura larvae statistically decreased along with the increase of the age of the larvae, with LC50 = 2.609 ng/cm(2) for neonatal larvae, LC50 = 28.778 ng/cm(2) for first instar larvae, LC50 = 70.460 ng/cm(2) for second instar larvae, and LC50 = 200.627 ng/cm(2) for third instar larvae. The accumulative mortality of 100% larvae appeared at 72 h for all instars of S. litura larvae, when feeding respectively with 83.22, 213.04, 341.40, and 613.20 ng/cm(2) of Vip3Aa toxin to the neonatal and first to third instar larvae. The histopathological effects of Vip3Aa toxin on the midgut epithelial cells of S. litura larvae was also investigated. The TEM observations showed wide damage of the epithelial cell in the midgut of S. litura larvae fed with Vip3Aa toxin.

  12. Primeiro relato de Trichogramma rojasi parasitando ovos de Spodoptera frugiperda First report of Trichogramma rojasi parasitizing eggs of Spodoptera frugiperda

    Directory of Open Access Journals (Sweden)

    Cátia Camera

    2010-08-01

    Full Text Available A larva de Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera: Noctuidae, conhecida como lagarta-do-cartucho, é um dos principais insetos-praga da cultura do milho e seu controle é realizado com produtos químicos. Uma alternativa é o controle biológico, em especial, com parasitoides de ovos do gênero Trichogramma Westwood, 1833 (Hymenoptera: Trichogrammatidae. Para a efetiva aplicação do controle biológico, é necessário avaliar o complexo de espécies/linhagens que ocorrem em ovos de S. frugiperda. Com esse objetivo, foram realizadas coletas de posturas de S. frugiperda na cultura do milho, no 10o Distrito de Arroio Grande, em Santa Maria, Rio Grande do Sul (RS, onde foi verificada a primeira ocorrência de Trichogramma rojasi Nagaraja & Nagarkatti, 1973 (Hymenoptera: Trichogrammatidae, parasitando ovos de S. frugiperda. A ocorrência de T. rojasi em ovos de S. frugiperda abre perspectivas para que esse parasitoide seja estudado a fim de integrar programas de controle biológico em milho, no Estado do Rio Grande do Sul.The larvae of Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera: Noctuidae, known as fall armyworm, is the main insect pest of corn crop and its control is done with chemicals. An alternative is biological control, in particular, the egg parasitoids of the genus Trichogramma Westwood, 1833 (Hymenoptera: Trichogrammatidae. For the effective application of biological control, it is necessary to evaluate the complex of species/strains occurring in eggs of S. frugiperda. With this objective, samples of egg masses of S. frugiperda were taken in the corn crop in the 10th Distrito de Arroio Grande, Santa Maria, Rio Grande do Sul State, where it was observed the first occurrence of Trichogramma rojasi Nagaraja & Nagarkatti, 1973 (Hymenoptera: Trichogrammatidae parasitizing eggs of S. frugiperda.. The occurrence of T. rojasi in eggs of S. frugiperda opens perspective so that this parasitoid can be studied in order to

  13. Attraction, Feeding Preference, and Performance of Spodoptera frugiperda Larvae (Lepidoptera: Noctuidae) Reared on Two Varieties of Maize.

    Science.gov (United States)

    De La Rosa-Cancino, Wilmar; Rojas, Julio C; Cruz-Lopez, Leopolodo; Castillo, Alfredo; Malo, Edi A

    2016-04-01

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is an economically important pest of maize and other crops in the Americas. Studies suggest that modern varieties of maize lost some of their natural defense mechanisms against herbivores during domestication and agricultural selection. In the present study, we evaluated the attraction, feeding preference (host fidelity and consumption rate), and performance of S. frugiperda larvae reared on hybrid (Pioneer P4063W) and landrace (Tuxpeño) varieties of maize. We also evaluated the damage caused by S. frugiperda to Pioneer and Tuxpeño maize plants in the field. We found that fifth-instar larvae were more attracted to Pioneer plants than to Tuxpeño plants in a Y-tube olfactometer. Additionally, the fall armyworm larvae showed more fidelity to Pioneer leaves than to Tuxpeño leaves. However, the larval consumption rate was similar for both types of maize plants. The life cycle of S. frugiperda was significantly longer when the larvae were reared on Tuxpeño leaves than on Pioneer leaves. In the field, the Pioneer variety was infested with more S. frugiperda larvae than the Tuxpeño variety. Thus, our results provide evidence that modern varieties of maize may have lost some of their defensive traits during selective breeding.

  14. Resistance to dual-gene Bt maize in Spodoptera frugiperda: selection, inheritance, and cross-resistance to other transgenic events.

    Science.gov (United States)

    Santos-Amaya, Oscar F; Rodrigues, João V C; Souza, Thadeu C; Tavares, Clébson S; Campos, Silverio O; Guedes, Raul N C; Pereira, Eliseu J G

    2015-12-17

    Transgenic crop "pyramids" producing two or more Bacillus thuringiensis (Bt) toxins active against the same pest are used to delay evolution of resistance in insect pest populations. Laboratory and greenhouse experiments were performed with fall armyworm, Spodoptera frugiperda, to characterize resistance to Bt maize producing Cry1A.105 and Cry2Ab and test some assumptions of the "pyramid" resistance management strategy. Selection of a field-derived strain of S. frugiperda already resistant to Cry1F maize with Cry1A.105 + Cry2Ab maize for ten generations produced resistance that allowed the larvae to colonize and complete the life cycle on these Bt maize plants. Greenhouse experiments revealed that the resistance was completely recessive (Dx = 0), incomplete, autosomal, and without maternal effects or cross-resistance to the Vip3Aa20 toxin produced in other Bt maize events. This profile of resistance supports some of the assumptions of the pyramid strategy for resistance management. However, laboratory experiments with purified Bt toxin and plant leaf tissue showed that resistance to Cry1A.105 + Cry2Ab2 maize further increased resistance to Cry1Fa, which indicates that populations of fall armyworm have high potential for developing resistance to some currently available pyramided maize used against this pest, especially where resistance to Cry1Fa was reported in the field.

  15. Resistance to dual-gene Bt maize in Spodoptera frugiperda: selection, inheritance, and cross-resistance to other transgenic events

    Science.gov (United States)

    Santos-Amaya, Oscar F.; Rodrigues, João V. C.; Souza, Thadeu C.; Tavares, Clébson S.; Campos, Silverio O.; Guedes, Raul N.C.; Pereira, Eliseu J.G.

    2015-01-01

    Transgenic crop “pyramids” producing two or more Bacillus thuringiensis (Bt) toxins active against the same pest are used to delay evolution of resistance in insect pest populations. Laboratory and greenhouse experiments were performed with fall armyworm, Spodoptera frugiperda, to characterize resistance to Bt maize producing Cry1A.105 and Cry2Ab and test some assumptions of the “pyramid” resistance management strategy. Selection of a field-derived strain of S. frugiperda already resistant to Cry1F maize with Cry1A.105 + Cry2Ab maize for ten generations produced resistance that allowed the larvae to colonize and complete the life cycle on these Bt maize plants. Greenhouse experiments revealed that the resistance was completely recessive (Dx = 0), incomplete, autosomal, and without maternal effects or cross-resistance to the Vip3Aa20 toxin produced in other Bt maize events. This profile of resistance supports some of the assumptions of the pyramid strategy for resistance management. However, laboratory experiments with purified Bt toxin and plant leaf tissue showed that resistance to Cry1A.105 + Cry2Ab2 maize further increased resistance to Cry1Fa, which indicates that populations of fall armyworm have high potential for developing resistance to some currently available pyramided maize used against this pest, especially where resistance to Cry1Fa was reported in the field. PMID:26675246

  16. The cushion–star Parvulastra exigua in South Africa: one species or more?

    Science.gov (United States)

    Payne, Robyn P.; Griffiths, Charles L.; von der Heyden, Sophie; Koch, Erich

    2015-01-01

    Abstract The cushion–star Parvulastra exigua (Lamarck, 1816) is a widely distributed member of the temperate intertidal fauna in the southern hemisphere. In South Africa, it occurs in sympatry with the endemic Parvulastra dyscrita (Clark, 1923), the two species being differentiated predominantly by gonopore placement. Several recent studies have suggested that there may be additional cryptic species within the Parvulastra exigua complex in South Africa, based variously on color morphology, genetic evidence and the differential placement of the gonopores. This paper attempts to resolve whether one or more species are represented within Parvulastra exigua. A total of 346 Parvulastra exigua and 8 Parvulastra dyscrita were collected from sites on the west and south–west coasts of South Africa; morphological, anatomical and genetic analyses were performed to determine whether cryptic species and/or Parvulastra exigua specimens with aboral gonopores were present. Results show that neither cryptic species nor Parvulastra exigua specimens with aboral gonopores occur at these sites. This study thus refutes previous claims of the existence of aboral gonopores in South African Parvulastra exigua, and suggests that a single species is represented. The distinction between Parvulastra exigua and Parvulastra dyscrita is also confirmed, and features separating these two species are clarified and documented. PMID:26478703

  17. Bacillus thuringiensis Cry1Ca-resistant Spodoptera exigua lacks expression of one of four Aminopeptidase N genes

    NARCIS (Netherlands)

    Herrero, S.; Gechev, T.; Bakker, P.L.; Moar, W.; Maagd, de R.A.

    2005-01-01

    BACKGROUND: Insecticidal toxins from Bacillus thuringiensis bind to receptors on midgut epithelial cells of susceptible insect larvae. Aminopeptidases N (APNs) from several insect species have been shown to be putative receptors for these toxins. Here we report the cloning and expression analysis of

  18. Effect of the flavonoid rutin on the biology of Spodoptera frugiperda (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Talita Roberta Ferreira Borges Silva

    2016-04-01

    Full Text Available The fall armyworm Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae is a major pest of maize crops in Brazil. The effects of plant metabolites on the biology and behavior of insects is little studied. The aim of the study was to evaluate the activity of rutin on the biology of the S. frugiperda by using artificial diets containing rutin. The study evaluated four treatments: regular diet (control group and diets containing 1.0, 2.0 and 3.0 mg g-1 of rutin. The following biological variables parameters of the larvae were evaluated daily: development time (days, larval and pupal weight (g and viability (%, adult longevity and total life cycle (days. A completely randomized experimental design was used with 25 replication. The rutin flavonoid negatively affected the biology of S. frugiperda by prolonging the larval development time, reducing the weight of larvae and pupae and decreasing the viability of the pupae. The addition of different concentrations of rutin prolonged the S. frugiperda life cycle. The use of plant with insecticidal activity has the potential with strategy in IPM.

  19. Identification and Characterization of Pathogen-Response Genes (repat) in Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Machado, Vilmar; Serrano, Jose; Galián, Jose

    2016-01-01

    The fall armyworm (Spodoptera frugiperda, Noctuidae, Lepidoptera) is one of the most important crop pests in the Americas, causing significant damage to maize, rice and sorghum. The mechanisms that determine its defences against pathogens are particularly relevant for the development of management and control strategies. We used an in silico approach to identify and characterize pathogen response genes (repat) present in different tissue libraries of S. fugiperda. The analyses revealed complete cDNA for nine repat genes; of these, repat15 and repat39 were found in libraries from a specific tissue--the midgut of larvae fed with xenobiotic substances. High expression levels of some genes were found in different libraries: 39 hits in repat30 in challenged hemocytes, 16 hits in repat31 in fat body, 10 hits in repat32 in fat body and 10 in challenged hemocytes, and 10 hits in repat38 in midgut of non-treated larvae and midgut of larvae fed with natural and xenobiotic substances. The genes corresponded to two ontology categories, stress response and immune response, and their phylogenetic relationships, nucleotide similarity, number of amino acid residues and molecular weights agree with what has been described for repat genes. It is noteworthy that proteins encoded by the repat genes of S. frugiperda have important defence functions in other tissues beyond midgut and that their functional categories are likely diverse, as they are related to cell envelope structure, energy metabolism, transport and binding.

  20. Insensitive trypsins are differentially transcribed during Spodoptera frugiperda adaptation against plant protease inhibitors.

    Science.gov (United States)

    de Oliveira, Caio Fernando Ramalho; de Paula Souza, Thaís; Parra, José Roberto Postali; Marangoni, Sergio; Silva-Filho, Marcio de Castro; Macedo, Maria Ligia Rodrigues

    2013-05-01

    0The fall armyworm (Spodoptera frugiperda) is an important pest insect due to high degree of polyphagia. In order to better understand its adaptation mechanism against plant protease inhibitors, bioassays were carried supplementing diet with the Kunitz trypsin inhibitor from Entada acaciifolia seeds (EATI). In vitro assays showed an increase of proteolytic activity in EATI-fed larvae midgut. Moreover, the trypsin enzymes showed insensitivity to inhibition with EATI. In order to understand what genes were overexpressed after chronic exposition to EATI, quantitative RT-PCR analyses were performed and revealed an increase in transcription of two trypsin genes, suggesting its participation in insensitivity of midgut trypsins. Another important result was the expression of one chymotrypsin gene, which is not expressed in control fed-larvae but induced in EATI-fed larvae. New regions of higher molecular weight showing proteolytic activity were visualized in inhibitor-fed larvae by zymography gel electrophoresis, proposing that the new enzymes expressed in response of inhibitor dietary would be formatting oligomers. This is a characteristic also observed in other pest insects that adapt to feed in plant protease inhibitors diet. Additional assays revealed that trypsins from EATI-fed larvae also became insensitive against Kunitz and Bowman-Birk inhibitors from soybean. This result suggests a possible involvement of the same S. frugiperda genes in adaptation against Kunitz and Bowman-Birk inhibitors in their host plants.

  1. Host association of Spodoptera frugiperda (Lepidoptera: Noctuidae) corn and rice strains in Argentina, Brazil, and Paraguay.

    Science.gov (United States)

    Juárez, M Laura; Murúa, M Gabriela; García, M Gabriela; Ontivero, Marta; Vera, M Teresa; Vilardi, Juan C; Groot, Astrid T; Castagnaro, Atilio P; Gastaminza, Gerardo; Willink, Eduardo

    2012-04-01

    Spodoptera frugiperda (J.E. Smith) is composed of two genetically distinct strains, the so-called corn strain and the rice strain. Whether the two strains differ in their host use is unclear, because laboratory experiments have not been able to show consistent host performance or preference differences between them, and field studies showed high rates of hybridization, as well as some degree asymmetric host use. To determine the distribution of the two strains and their association with host plants, we collected fall armyworm larvae from different crops (corn, rice, alfalfa, and sorghum) and grasses in 15 different localities over 4 yr in Argentina, Brazil, and Paraguay. The strain identity was analyzed using two polymorphisms in the mitochondrial cytochrome oxidase subunit I gene. We identified the corn and rice haplotypes and three types of populations were characterized based on the frequencies of the individuals that belonged to any of these haplotypes: in 44% of populations the corn haplotype predominated, in 44% of populations the rice haplotype was the most frequent, and 11% of populations showed both haplotypes at similar proportions. In total, eight populations (47%) showed the expected pattern, two populations (12%) were polymorphic within the same field, and seven populations (41%) showed the inverse pattern. Taken together, there was no consistent pattern of host association between the two sympatric genotypes and their respective host plants. This investigation supports the need for additional studies to determine which other forces keep the genotypes separate, and what is the degree of genetic differentiation between these populations.

  2. Relationship between abundance and morphology of benthic foraminifera Epistominella exigua: Palaeoclimatic implications

    Digital Repository Service at National Institute of Oceanography (India)

    Saraswat, R.; Deopujari, A; Nigam, R.; Henriques, P.J.

    The relationship between abundance (relative as well as absolute abundance) and morphology (size of the shell, numbers and proloculus size) of benthic foraminifera Epistominella exigua has been studied in a core to understand the influence...

  3. Redescription of Campoletis sonorensis (Cameron, 1886) (Hymenoptera, Ichneumonidae, Campopleginae), parasitoid of Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera, Noctuidae) in Brazil.

    Science.gov (United States)

    Camargo, L F; Brito, R A; Penteado-Dias, A M

    2015-11-01

    The fall armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae) is a voracious pest of numerous crops of economic importance throughout the New World. In Brazil, its larvae are attacked by several species of parasitoid wasps, making them potential candidate as biological control agents against this pest. A survey of the parasitoid fauna on S. frugiperda in maize crops throughout Brazil reveals two species of Campoletis, which are morphologicaly very similar species. In this paper we combine these data with pictures from the type material of C. sonorensis and C. flavicincta, as well as their descriptions to provide a redescription to Campoletis sonorensis (Cameron, 1886) using for this both morphological characters and DNA Barcoding (Hebert et al., 2003) information, in an attempt to help with the correct identification of the taxa to improve biological control studies.

  4. Redescription of Campoletis sonorensis (Cameron, 1886 (Hymenoptera, Ichneumonidae, Campopleginae, parasitoid of Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera, Noctuidae in Brazil

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    L. F. Camargo

    Full Text Available Abstract The fall armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae is a voracious pest of numerous crops of economic importance throughout the New World. In Brazil, its larvae are attacked by several species of parasitoid wasps, making them potential candidate as biological control agents against this pest. A survey of the parasitoid fauna on S. frugiperda in maize crops throughout Brazil reveals two species of Campoletis, which are morphologicaly very similar species. In this paper we combine these data with pictures from the type material of C. sonorensis and C. flavicincta, as well as their descriptions to provide a redescription to Campoletis sonorensis (Cameron, 1886 using for this both morphological characters and DNA Barcoding (Hebert et al., 2003 information, in an attempt to help with the correct identification of the taxa to improve biological control studies.

  5. Antiamoebic activity of marine sponge Haliclona exigua (Krikpatrick

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    V Lakshmi

    2009-03-01

    Full Text Available The methanol and methanol-chloroform (1:1 extracts of the freshly collected Haliclona exigua showed minumim inhibitory concentration (MIC of 125 ug/ml and 250 ug/ml respectively in in vitro studies, but when both of these were tested in vivo in rats, only methanol-chloroform showed 80% inhibition of trophozoites at the dose of 900 mg/kg body weight against Entamoeba histolytica. Therefore only methanol-chloroform extract was further fractionated into four fractions (hexane, chloroform, n-butanol soluble and n-butanol insoluble fractions. Out of these, only hexane and n-butanol soluble fractions showed 80% inhibition of trophozoites at 900 mg/kg dose. Further the chromatography of the n-butanol fraction yielded araguspongin-C which showed promising results at different doses.

  6. Impact of insecticides used to control Spodoptera frugiperda (J.E. Smith in corn on survival, sex ratio, and reproduction of Trichogramma pretiosum Riley offspring

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    Jander R Souza

    2013-06-01

    Full Text Available Corn (Zea mays L. is cultivated in large areas and considered one of the world's major cereal crops. There are several arthropod pests that can reduce its production such as the fall armyworm, Spodoptera frugiperda (J.E. Smith (Lep.: Noctuidae, which is considered to be the main pest for corn. Fall armyworm is primarily controlled by insecticides. The use of biological control agents to manage this pest is growing with an emphasis on the egg parasitoid Trichogramma pretiosum Riley (Hym.: Trichogrammatidae. Thus, the aim of this research was to evaluate the impact of the following insecticides (g ai L-1 beta-cypermethrin (0.03, chlorfenapyr (0.60, chlorpyrifos (0.96, spinosad (0.16, etofenprox (0.10, triflumuron (0.08, alfa-cypermethrin/teflubenzuron (0.0425/0.0425, and lambda-cyhalothrin/thiamethoxam (0.11/0.083 on survival, sex ratio, reproduction, and T. pretiosum offspring. Distilled water was used as a control. Commercial insecticide formulations were diluted in distilled water. Bioassays used Anagasta kuehniella eggs treated with insecticides which were afterwards exposed to parasitism. Bioassays were conducted under controlled conditions at 25 ± 2 °C, 70 ± 10% RH, and 12:12 h photoperiod. Alfa-cypermethrin/teflubenzuron, beta-cypermethrin, chlorpyrifos, chlorfenapyr, spinosad, etofenprox, and lambda-cyhalothrin/thiamethoxam reduced parasitism capacity of maternal generation females as well as the percentage of insect emergence from the F1 generation. Only triflumuron was selective for T. pretiosum and can be recommended along with this parasitoid in fall armyworm management programs in corn.

  7. Cannibalism and virus production in Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) larvae fed with two leaf substrates inoculated with Baculovirus spodoptera.

    Science.gov (United States)

    Valicente, F H; Tuelher, E S; Pena, R C; Andreazza, R; Guimarães, M R F

    2013-04-01

    Cannibalism in the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) (FAW), is a limiting factor in a baculovirus production system. To detect the impact of cannibalism, a two-step bioassay was conducted with different larval ages of FAW fed on two food sources (corn and castor bean leaves) contaminated with the S. frugiperda multiple-embedded nucleopolyhedrovirus. In a first bioassay, the food source affected the cannibalism, being higher for all larval ages tested (5-, 6- and 7-day-old larvae) in larvae fed on corn than on those fed on castor bean leaves. Larval mortality, weight equivalent and larval equivalents (LEs) per hectare decreased as the larval age increased. Larval weight, occlusion bodies (OBs)/larva and total OBs increased when the larval age increased. In a second bioassay, in which only 6- and 7-day-old larvae were used because of the performance in the first bioassay, the cannibalism rates were affected by the interaction between food sources and time of feeding (48 and 72 h), reaching the highest values for 6- and 7-day-old larvae fed on corn leaves for 72 h. Mortality of the FAW was affected by the interaction between food sources, larval age and time of feeding. The lowest mortalities were on 7-day-old larvae when they were fed on castor bean leaves for 48 and 72 h. Larval weight, OBs/larva, total OBs and LEs were affected by the interaction between food sources and larval age. A significant correlation was observed between larval weight and OBs/larva that fed on both food sources, suggesting that larval weight can be used to achieve a concentration to be sprayed in 1 ha.

  8. Phylogenetic molecular species delimitations unravel potential new species in the pest genus Spodoptera Guenee, 1852 (Lepidoptera, Noctuidae.

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    Pascaline Dumas

    Full Text Available Nowadays molecular species delimitation methods promote the identification of species boundaries within complex taxonomic groups by adopting innovative species concepts and theories (e.g. branching patterns, coalescence. As some of them can efficiently deal with large single-locus datasets, they could speed up the process of species discovery compared to more time consuming molecular methods, and benefit from the existence of large public datasets; these methods can also particularly favour scientific research and actions dealing with threatened or economically important taxa. In this study we aim to investigate and clarify the status of economically important moths species belonging to the genus Spodoptera (Lepidoptera, Noctuidae, a complex group in which previous phylogenetic analyses and integrative approaches already suggested the possible occurrence of cryptic species and taxonomic ambiguities. In this work, the effectiveness of innovative (and faster species delimitation approaches to infer putative species boundaries has been successfully tested in Spodoptera, by processing the most comprehensive dataset (in terms of number of species and specimens ever achieved; results are congruent and reliable, irrespective of the set of parameters and phylogenetic models applied. Our analyses confirm the existence of three potential new species clusters (for S. exigua (Hübner, 1808, S. frugiperda (J.E. Smith, 1797 and S. mauritia (Boisduval, 1833 and support the synonymy of S. marima (Schaus, 1904 with S. ornithogalli (Guenée, 1852. They also highlight the ambiguity of the status of S. cosmiodes (Walker, 1858 and S. descoinsi Lalanne-Cassou & Silvain, 1994. This case study highlights the interest of molecular species delimitation methods as valuable tools for species discovery and to emphasize taxonomic ambiguities.

  9. Survival and larval development of Spodoptera frugiperda (J E Smith) (Lepidoptera: Noctuidae) on alternatives host; Sobrevivencia e desenvolvimento larval de Spodoptera frugiperda (J E Smith) (Lepidoptera: Noctuidae) em hospedeiros alternativos

    Energy Technology Data Exchange (ETDEWEB)

    Sa, Verissimo G.M. de [Universidade Federal de Minas Gerais (UFMG), Montes Claros, MG (Brazil). Dept. de Agronomia; Fonseca, Bernardo V.C. [Universidade FUMEC, Belo Horizonte, MG (Brazil); Boregas, Katia G.B. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Ecologia; Waquil, Jose M. [EMBRAPA Milho e Sorgo, Sete Lagoas, MG (Brazil)]. E-mail: aaquil@cnpms.embrapa.br

    2009-01-15

    Two bioassays were conducted to evaluate the suitability of host plants of fall armyworm (FAW), Spodoptera frugiperda (J E Smith), in the Brazilian agro-ecosystem. Larval development and survival were analyzed by infesting leaves of maize, grain sorghum, Johnson grass, soybean, Brachiaria and tobacco with FAW newly hatched larvae in a no choice test. No significant differences of survival were observed among insects reared on different hosts, except for tobacco, where no survivors were recorded. Larvae fed on soybean and artificial diet grew larger than those fed on the other hosts. The heaviest pupa was observed from larva fed on artificial diet and the lighter from larva fed on Brachiaria grass. No significant differences were reported on larval development time on natural hosts, but it was longer for larvae reared on artificial diet. Three classes of larval development time were observed on maize, four on sorghum, Brachiaria and soybean, and five on artificial diet. Nearly 85% of FAW larvae completed development within 12 d on maize; 77% on grain sorghum, 80% on Johnson grass, 68% on Brachiaria and 83% on soybean within 14 d and 69% on artificial diet within 17 d. The host suitability to FAW decreases from maize to sorghum, soybean and Brachiaria. (author)

  10. BIOLOGIA DE Spodoptera frugiperda (J. SMITH (LEPIDOPTERA: NOCTUIDAE EM FOLHAS DE MANDIOCA (Manihot esculenta, CRANTZ

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    Gislane da Silva Lopes

    2008-01-01

    Full Text Available Spodoptera frugiperda is a species polyphagous that attacks several cultures economically important in various countries. It is known in the larval phases as fall armyworm and it is to main curse of the culture of the corn in Brazil.It was found recently fed her in plantings of cassava in São Luís and Itapecuru Mirim (MA. As the knowledge of the biology of the insect is of fundamental importance for the development of handling strategies, inside of the integrated handling of curses, the work aimed at to study the biology and the behavior of S. frugiperda in cassava leaves, maids in laboratory conditions. 60 coming caterpillars of the creation were used in articial diet. After the appearance the larvas were individualized in disposable plastic glasses with capacity for 100 ml and fed with cassava leaves, that they were changed every other day, or according to need. The experiment was led in climate chamber, regulated for temperature of 25°C, relative humidity of 60 + 10% and fotofase of 14 hours. The appraised biological parameters demonstrated the medium duration of the total cycle of 39,93 days, distributed in 6 or 7 you urge, where the species presented larval viability, pupal and of superior adult to 75% and, percentile of of 4% and 22,97% in pupas and adults, respectively. The fecundity was of 70,84% and the adults' of 77,08% viability. Being ended that the culture of the cassava assists to the demands nutricionais of S. frugiperda.

  11. Assessment of electron beam-induced abnormal development and DNA damage in Spodoptera litura (F.) (Lepidoptera: Noctuidae)

    Science.gov (United States)

    Yun, Seung-Hwan; Lee, Seon-Woo; Koo, Hyun-Na; Kim, Gil-Hah

    2014-03-01

    The armyworm, Spodoptera litura (F.) is a polyphagous and important agricultural pest worldwide. In this study, we examined the effect of electron beam irradiation on developmental stages, reproduction, and DNA damage of S. litura. Eggs (0-24 h old), larvae (3rd instar), pupae (3 days old after pupation), and adults (24 h after emergence) were irradiated with electron beam irradiation of six levels between 30 and 250 Gy. When eggs were irradiated with 100 Gy, egg hatching was completely inhibited. When the larvae were irradiated, the larval period was significantly delayed, depending on the doses applied. At 150 Gy, the fecundity of adults that developed from irradiated pupae was entirely inhibited. However, electron beam irradiation did not induce the instantaneous death of S. litura adults. Reciprocal crosses between irradiated and unirradiated moths demonstrated that females were more radiosensitive than males. We also conducted the comet assay immediately after irradiation and over the following 5 days period. Severe DNA fragmentation in S. litura cells was observed just after irradiation and the damage was repaired during the post-irradiation period in a time-dependent manner. However, at more than 100 Gy, DNA damage was not fully recovered.

  12. Susceptibility and aversion of Spodoptera frugiperda (Lepidoptera: Noctuidae) to Cry1F Bt maize and considerations for insect resistance management.

    Science.gov (United States)

    Binning, Rachel R; Coats, Joel; Kong, Xiaoxiao; Hellmich, Richard L

    2014-02-01

    Bacillus thuringiensis (Bt) maize was developed primarily for North American pests such as European corn borer (Ostrinia nubilalis (Hübner)). However, most Bt maize products are also cultivated outside of North America, where the primary pests may be different and may have lower susceptibility to Bt toxins. Fall armyworm (Spodoptera frugiperda JE Smith) is an important pest and primary target of Bt maize in Central and South America. S. frugiperda susceptibility to Cry1F (expressed in event TC1507) is an example of a pest-by-toxin interaction that does not meet the high-dose definition. In this study, the behavioral and toxic response of S. frugiperda to Cry1F maize was investigated by measuring the percentage of time naive third instars spent feeding during a 3-min exposure. S. frugiperda also were exposed as third instars to Cry1F maize for 14 d to measure weight gain and survival. S. frugiperda demonstrated an initial, postingestive aversive response to Cry1F maize, and few larvae survived the 14 d exposure. The role of susceptibility and avoidance are discussed in the context of global IRM refuge strategy development for Bt products.

  13. Frequency of Cry1F Non-Recessive Resistance Alleles in North Carolina Field Populations of Spodoptera frugiperda (Lepidoptera: Noctuidae)

    Science.gov (United States)

    Li, Guoping; Reisig, Dominic; Miao, Jin; Gould, Fred; Huang, Fangneng; Feng, Hongqiang

    2016-01-01

    Fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is a target species of transgenic corn (Zea mays L.) that expresses single and pyramided Bacillus thuringiensis (Bt) toxin. In 2014, S. frugiperda were collected from a light trap in North Carolina, and a total of 212 F1/F2 isofemale lines of S. frugiperda were screened for resistance to Bt and non-Bt corn. All of the 212 isolines were susceptible to corn tissue expressing Cry1A.105 + Cry2Ab, Cry1F + Cry1A.105 + Cry2Ab, and Cry1F + Cry1Ab + Vip3Aa20. Growth rate bioassays were performed to isolate non-recessive Bt resistance alleles. Seven individuals out of the 212 isofemale lines carried major non-recessive alleles conferring resistance to Cry1F. A pooled colony was created from the seven individuals. This colony was 151.21 times more resistant to Cry1F than a known-susceptible population and was also resistant to Cry1A.105, but was not resistant to Cry2Ab and Vip3Aa20. The results demonstrate that field populations of S. frugiperda collected from North Carolina are generally susceptible to Cry1F, but that some individuals carry resistant alleles. The data generated in this study can be used as baseline data for resistance monitoring. PMID:27119741

  14. Frequency of Cry1F Non-Recessive Resistance Alleles in North Carolina Field Populations of Spodoptera frugiperda (Lepidoptera: Noctuidae.

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    Guoping Li

    Full Text Available Fall armyworm, Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae, is a target species of transgenic corn (Zea mays L. that expresses single and pyramided Bacillus thuringiensis (Bt toxin. In 2014, S. frugiperda were collected from a light trap in North Carolina, and a total of 212 F1/F2 isofemale lines of S. frugiperda were screened for resistance to Bt and non-Bt corn. All of the 212 isolines were susceptible to corn tissue expressing Cry1A.105 + Cry2Ab, Cry1F + Cry1A.105 + Cry2Ab, and Cry1F + Cry1Ab + Vip3Aa20. Growth rate bioassays were performed to isolate non-recessive Bt resistance alleles. Seven individuals out of the 212 isofemale lines carried major non-recessive alleles conferring resistance to Cry1F. A pooled colony was created from the seven individuals. This colony was 151.21 times more resistant to Cry1F than a known-susceptible population and was also resistant to Cry1A.105, but was not resistant to Cry2Ab and Vip3Aa20. The results demonstrate that field populations of S. frugiperda collected from North Carolina are generally susceptible to Cry1F, but that some individuals carry resistant alleles. The data generated in this study can be used as baseline data for resistance monitoring.

  15. Effects of silicon on the penetration and reproduction events of Meloidogyne exigua on coffee roots

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    Rodrigo Vieira Silva

    2015-06-01

    Full Text Available Considering that the root-knot nematode Meloidogyne exigua has caused great yield losses to coffee production in Brazil, this study aimed to determine whether the penetration and the reproduction events of this nematode on the roots of plants from two coffee cultivars with different levels of basal resistance to this nematode could be affected by silicon (Si. Coffee plants from the cultivars Catuaí and IAPAR 59, which are susceptible and resistant, respectively, to M. exigua, were grown in pots containing Si-deficient soil that was amended with either calcium silicate (+Si or calcium carbonate (–Si. The Si concentration on the root tissue significantly increased by 159 and 97% for the +Si plants from the cultivars Catuaí and IAPAR 59, respectively, compared to the –Si plants of these cultivars. The population of M. exigua, the number of galls and the number of eggs were significantly reduced on the roots of the +Si plants of the cultivars Catuaí and IAPAR 59 compared to the –Si plants of these cultivars. It was concluded that the development and reproduction events of M. exigua were negatively impacted on the roots of coffee plants supplied with Si.

  16. INSETICIDAL OILS FROM AMAZON PLANTS IN CONTROL OF FALL ARMYWORM

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    ANA CLÁUDIA VIEIRA DOS SANTOS

    2016-01-01

    Full Text Available The potential insecticidal of oils from southwestern Amazon plants against Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae was investigated. Initial bioassays were performed with undiluted oils from 11 plant species. The efficacy of the oils was evaluated against eggs and third-instar caterpillars of S. frugiperda. The oils of Copaifera sp. (Leguminosae, Orbignya phalerata (Arecaceae, and Carapa guianensis (Meliaceae displayed a high efficacy against the caterpillars and were used in subsequent concentration-response bioassays, at concentrations established through preliminary tests. The highest nonlethal concentrations of oils and the lowest lethal concentrations were calculated. A completely randomized design was adopted in both bioassays. The LC50 of the oils varied from 7.50 to 60.84% (v/v. Copaifera sp. oil had the highest toxicity and was 6.84-fold more toxic than O. phalerata oil and 8.11-fold more toxic than Carapa guianensis oil. In general, oils from Copaifera sp., O. phalerata, and Carapa guianensis were effective in controlling S. frugiperda caterpillars under laboratory conditions, and are good candidates for use in integrated management programs of corn pests.

  17. AISLAMIENTO, IDENTIFICACIÓN Y CARACTERIZACIÓN DE NUCLEOPOLIEDROVIRUS NATIVOS DE SPODOPTERA FRUGIPERDA EN COLOMBIA ISOLATION, IDENTIFICATION AND CHARACTERIZATION OF NATIVE NUCLEOPOLYHEDROVIRUS OF SPODOPTERA FRUGIPERDA IN COLOMBIA

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    Juliana Andrea Gómez Valderrama

    2010-12-01

    Full Text Available El gusano cogollero del maíz Spodoptera frugiperda (J.E. Smith es considerado la plaga más importante del cultivo en el mundo. En varios países se han empleado exitosamente los nucleopoliedrovirus de la familia Baculoviridae para su control. Sin embargo, en Colombia, no se cuenta ningún bioplaguicida viral registrado para el control de la plaga. En el presente trabajo, se realizó la búsqueda de aislamientos nativos de nucleopoliedrovirus en los departamentos de Tolima, Meta y Córdoba, mediante la recolección de larvas en diferentes cultivos. Las muestras fueron analizadas por microscopía para la búsqueda de partículas virales y los aislamientos encontrados se caracterizaron física y biológicamente. Se recolectaron 2.140 larvas de S. frugiperda en los tres departamentos muestreados. Sin embargo, sólo en un lugar (Cereté, Córdoba, se encontraron larvas con síntomas de infección viral en campo. El 2% de las muestras colectadas mostraron síntomas típicos de infección y en total se identificaron 3 aislamientos codificados como NPV003 (Córdoba, NPV009 (Tolima y NPV011 (Meta. Los aislamientos presentaron un tamaño de partícula entre 1,93 µm y 2,14 µm. Las concentraciones letales medias (CL50 sobre larvas neonatas oscilaron entre 2,2 x 105 CI/mL y 7,0 x 105 CI/mL y no se registraron estadísticas entre los aislamientos, sugiriendo que todos tienen la misma patogenicidad sobre larvas neonatas del insecto. Estos virus nativos representan la base para el desarrollo de una nueva alternativa biológica para el control de la plaga, siendo necesario iniciar los estudios para su formulación.Worldwide, the fall armyworm Spodoptera frugiperda (J.E. Smith is considered the most important pest of maize crop. Nucleopolyhedrovirus of Baculoviridae family have been successfully used in several countries for its control. However, in Colombia there are not any biopesticide registered for the control of this pest. In the present work, native

  18. Novel Chromone Derivatives from Marine Fungus Aspergillus versicolor Isolated from the Sponge Xestospongia exigua

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    From the marine sponge Xestospongia exigua, fungal isolates of Aspergillus versicolor (Vuill)Triab were obtained. Isolation and purification of ethyl acetate extracts from culture filtrates of the fungus led to yield six new chromone derivatives namely aspergione A, aspergione B, aspergione C, aspergione D, aspergione E, aspergione F. The structures of all the new compounds were established on the basis of extensive spectroscopy (UV, MS, 1H and 13C NMR, COSY, HMQC and HMBC) analysis.

  19. Host Plant Selection and Nutrient Utilization of Beet Armyworm Larvae%甜菜夜蛾幼虫对寄主植物的选择及营养利用

    Institute of Scientific and Technical Information of China (English)

    范锦胜; 张李香; 王贵强; 马淑梅; 邵红涛

    2011-01-01

    In order to explore the larval damage of Spodoptera exigua on different host plants, Chenopodium album L., Amaranthus mangostanu, Beta vulgaris and Allium fistulosum L. Were assessed by selection tests feeding preferences and the nutritional utilization of S. Exigua. The results indicated that the preference of 1st instar larva to the four plants was C. Album L., A. Mangostanu, B. Vulgaris and A. Fistulosum L.. Feeding preference of the 3rd instar larva was not as obvious as the 1st instar larva. And the host plant feeding preference of 3rd instar larva was weakened with the prolonged observation period. The nutrition indexes of 3rd instar larvae on consumption of the four host plants indicated that the relative growth rate (RGR) and efficiency of conversion of digested food (ECU) in larva feeding on B. Vulgaris was significantly higher than that on the three plants; the relative consumption rate (RCR) and approximate digestibility (AD) in larva feeding on A. Fistulosum L and the efficiency of conversion of ingested food (ECI) in larva feeding on C. Album L. Was the highest. 3rd instar larva could seriously harm the B. Vulgaris and A. Fistulosum L.. Therefore, in the process of operation in agriculture, the 3-1 instar larvae should be strengthened monitoring and management.%为探讨甜菜夜蛾(Spodoptera exigua)幼虫对不同寄主植物的危害性,选取灰菜、苋菜、甜菜和葱4种植物进行了选择性实验,并同时研究了幼虫对4种植物的营养利用.结果表明:甜菜夜蛾1龄幼虫的趋性表现为灰菜、苋菜、甜菜、葱;3龄幼虫对寄主植物的选择性低于1龄幼虫,且随观测时间的延长,选择性明显减弱.取食甜菜组的幼虫相对生长率和食物转化率显著高于其余组;取食葱组的幼虫相对取食量和近似消化率显著高于其余组;取食灰菜组的食物利用率最高.甜菜夜蛾3龄幼虫可严重为害甜菜和葱.因此,在农业操作过程中,应加强对甜菜夜蛾3龄幼虫的监控和治理.

  20. Identification and characterization of the Spodoptera Su(var 3-9 histone H3K9 trimethyltransferase and its effect in AcMNPV infection.

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    Binbin Li

    Full Text Available Histone H3-lysine(9 (H3K9 trimethyltransferase gene Su(var 3-9 was cloned and identified in three Spodoptera insects, Spodopterafrugiperda (S. frugiperda, S. exigua and S. litura. Sequence analysis showed that Spodoptera Su(var 3-9 is highly conserved evolutionarily. Su(var 3-9 protein was found to be localized in the nucleus in Sf9 cells, and interact with histone H3, and the heterochromatin protein 1a (HP1a and HP1b. A dose-dependent enzymatic activity was found at both 27 °C and 37 °C in vitro, with higher activity at 27 °C. Addition of specific inhibitor chaetocin resulted in decreased histone methylation level and host chromatin relaxation. In contrast, overexpression of Su(var 3-9 caused increased histone methylation level and cellular genome compaction. In AcMNV-infected Sf9 cells, the transcription of Su(var 3-9 increased at late time of infection, although the mRNA levels of most cellular genes decreased. Pre-treatment of Sf9 cells with chaetocin speeded up viral DNA replication, and increased the transcription level of a variety of virus genes, whereas in Sf9 cells pre-transformed with Su(var 3-9 expression vector, viral DNA replication slow down slightly. These findings suggest that Su(var 3-9 might participate in the viral genes expression an genome replication repression during AcMNPV infection. It provided a new insight for the understanding virus-host interaction mechanism.

  1. Adequação de uma dieta artificial para os biótipos "milho" e "arroz" de Spodoptera frugiperda (Lepidoptera: Noctuidae Adaptation of an artificial diet for the biotypes "corn" and "rice" of Spodoptera frugiperda (Lepidoptera: Noctuidae

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    Gustavo Rossato Busato

    2006-01-01

    Full Text Available Spodoptera frugiperda é considerada uma das principais pragas da cultura do milho (lagarta-do-cartucho e do arroz irrigado (lagarta-da-folha, ocasionando altos índices de desfolhamento. O objetivo do estudo foi obter uma dieta artificial adequada para criar os biótipos "milho" e "arroz" de S. frugiperda (J.E. Smith, em laboratório. Os insetos foram coletados em áreas cultivadas com milho e arroz irrigado no ecossistema de várzea e a identificação foi realizada pela análise do DNA genômico. O desenvolvimento dos dois biótipos foi acompanhado sobre a dieta de Greene e a mesma dieta modificada a 25 ± 1ºC, UR de 70 ± 10% e fotofase de 14 horas. O estudo foi realizado com 150 lagartas por dieta, individualizadas em tubos de vidro e contendo dieta artificial. Por ocasião da emergência, 20 casais foram individualizados e alimentados com solução aquosa de mel a 10%. A dieta Greene possibilitou melhor desenvolvimento dos dois biótipos, proporcionando maior velocidade de desenvolvimento, maior massa de lagartas no máximo desenvolvimento, massa de pupas e fecundidade total, além de valores mais elevados da taxa líquida de reprodução, taxa intrínseca de crescimento e taxa finita de aumento.Spodoptera frugiperda is considered one of the main pest in corn and irrigated rice (fall armyworm crops, causing high leaf losses. The objective of this study was to obtain an appropriate artificial diet to rear the biotypes "corn" and "rice" of S. frugiperda in laboratory. The insects were collected in areas cultivated with corn and irrigated rice in the meadow ecosystem and the identification was accomplished by the analysis of the DNA genomic. The development of the two biotypes was accompanied on Greene's diet and the same diet modified to 25 ± 1ºC, UR of 70 10% and fotofase of 14 hours. The study was accomplished with 150 larvae by diet individualized in glass tubes containing artificial diet. At emergency 20 couples were individualized

  2. Efeitos de extratos de plantas na biologia de Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae mantida em dieta artificial Effects of plant extracts on the biology of Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae maintained under artificial diet

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    Gilberto Pedreira Santiago

    2008-06-01

    Full Text Available Avaliaram-se os efeitos dos extratos aquosos a 10% de folhas e ramos de arruda (Ruta graveolens L., folhas e ramos de melão-de-são-caetano (Momordica charantia L., folhas do alecrim-pimenta (Lippia sidoides Cham. e fruto verde de mamona (Ricinus communis L., sobre a biologia da lagarta-do-cartucho do milho (Spodoptera frugiperda, mantida em dieta artificial. Os parâmetros avaliados foram duração e viabilidade das fases larval e pupal, peso de pupa, fecundidade, fertilidade e longevidade de adultos. Larvas de S. frugiperda recém-eclodidas foram colocadas em tubos de ensaio com dieta artificial, contendo os extratos de cada material testado. O extrato aquoso do fruto verde de R. communis apresentou bioatividade, nos parâmetros duração larval e pupal e peso de pupa. O extrato aquoso de R. graveolens reduziu o peso de pupa. A dieta contendo extrato de folhas e ramos de M. charantia reduziu a viabilidade larval e o peso de pupa. O extrato aquoso de folhas de L. sidoides não afetou as fases larval e pupal, reduziu a postura e a viabilidade de ovos e aumentou a longevidade de adultos de S. frugiperda. A viabilidade de pupa não foi afetada pelos extratos testados.The effects of aqueous extracts, at 10% concentration of leaves and branches of Ruta graveolens L., leaves and branches of Momordica charantia L., leaves of Lippia sidoides Cham. and green fruits of Ricinus communis L. were evaluated on the biology of fall armyworm (Spodoptera frugiperda maintained under artificial diet. The evaluated parameters were: duration and viability of the larval and pupal phases, pupa weight, fecundity, fertility and longevity of adults. Just-hatched larvae of S. frugiperda was placed in test tube with artificial diet containing extracts of each tested material. The aqueous extract of the green fruits of R. communis presented bioactivity upon duration and weight of larval and pupal phases. The aqueous extract of R. graveolens reduced weight of pupa. The diet

  3. Impact of the number of Spodoptera frugiperda egg layers on parasitism by Trichogramma atopovirilia Impacto do número de camadas de ovos de Spodoptera frugiperda no parasitismo por Trichogramma atopovirilia

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    Eduardo Barbosa Beserra

    2005-04-01

    Full Text Available Egg parasitoids of the genus Trichogramma (Hymenoptera: Trichogrammatidae can be found in several crops attacking Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae eggs. It is therefore necessary to demonstrate the capacity of these natural enemies in suppressing populations of the pest to allow them to be used in biological control programs against that species. This work had the objective of evaluating the impact of egg layer distribution in S. frugiperda egg masses on the parasitism capacity of Trichogramma atopovirilia Oatman & Platner, 1983. Masses containing one, two, and three layers were used as treatments, and 1.6 parasitoid per egg of the pest were released. Parasitism percentage differences were observed among the three types of masses under study, on average 66.24 ± 8.56%, 45.20 ± 6.20%, and 40.10± 3.46% for egg masses with one, two, and three layers, respectively, demonstrating the potential of use of the parasitoid for the control of fall armyworm.Parasitóides de ovos do gênero Trichogramma (Hymenoptera: Trichogrammatidae ocorrem em diversas culturas atacando ovos de Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera: Noctuidae sendo necessário que se demonstre a capacidade desses inimigos naturais em suprimir a população da praga para que eles possam ser utilizados em programas de controle biológico daquela espécie. O trabalho teve como objetivo avaliar o impacto da distribuição dos ovos em camadas nas posturas de S. frugiperda sobre a capacidade de parasitismo de Trichogramma atopovirilia Oatman & Platner, 1983. Foram utilizadas como tratamentos posturas com uma, duas e três camadas e liberado 1.6 parasitóide por ovo da praga. Observaram-se diferenças quanto à porcentagem de parasitismo entre os três tipos de posturas estudados, sendo em média de 66,24 ± 8,56%, 45,20 ± 6,20% e 40,10 ± 3,46% para posturas com uma, duas e três camadas respectivamente, mostrando o potencial de utilização do

  4. The feeding preferences of Spodoptera frugiperda (J. E. SMITH (Lepidoptera: Noctuidae on cotton plant varieties=Preferência alimentar de Spodoptera frugiperda (J. E. SMITH (Lepidoptera: Noctuidae em variedades de plantas algodoeiras

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    Ostenildo Ribeiro Campos

    2012-04-01

    Full Text Available This work evaluated the attractiveness and the non-preference for feeding of newly hatched fall armyworm larvae on the cotton plant parts and different varieties used in the study. The trials were performed at 27 ± 1ºC, a 70% ± 10% relative humidity and a 14h photoperiod. Leaves, bracts, squares and carpel walls of the BRS Itamarati-90 variety and leaves of Fibermax-966, Fibermax-977, DeltaOpal, DeltaPenta, BRS Acala-90, Coodetec-408, Coodetec-409, Coodetec-410, BRS-Cedro, BRS-Ipê, BRS-Aroeira, IPR-96, IPR-120, BRS-Araçá, IAC-24 and BRS Itamarati-90 varieties were used in attractiveness, multiple-choice and confinement (no-choice non-preference feeding trials. Twenty larvae were released per petri dish test (arena system with 10 repetitions. Attractiveness trials were evaluated by counting feeding caterpillars over 60 min. and by measuring non-preference at 24h. Leaves were the most attractive item and were preferred for feeding. In the multiple-choice arena trials, Coodetec-410 was the most attractive variety, and BRS Acala-90, Fibermax-966 and DeltaPenta were the least attractive to fall armyworm larvae. In the non-preference trial, BRS-Araça was the variety favored for feeding. BRS-Cedro, BRS Itamarati-90, DeltaPenta, Coodetec-408 and BRS-Aroeira were the least-favored varieties. In the 60 min. attractiveness trials, 46 min. proved to be the most suitable time for evaluating the attractiveness of cotton plants to newly hatched fall armyworm larvae.Avaliou-se atratividade e não-preferência alimentar de lagartas recém-eclodidas de Spodoptera frugiperda por partes de plantas e plantas de variedades de algodoeiro. Testes foram realizados a 27 ± 1ºC, UR de 70% ± 10% e fotofase de 14h. Folhas, brácteas, botões florais e cascas de maçãs da variedade BRS Itamarati-90 e folhas de Fibermax-966, Fibermax-977, DeltaOpal, DeltaPenta, BRS Acala-90, Coodetec-408, Coodetec-409, Coodetec-410, BRS-Cedro, BRS-Ipê, BRS-Aroeira, IPR-96, IPR-120

  5. Influence of host plant nitrogen fertilization on haemolymph protein profiles of herbivore Spodoptera exigua and development of its endoparasitoid Cotesia marginiventris

    Science.gov (United States)

    Nitrogen has complex effects on plant-herbivore-parasitoid tri-trophic interactions. The negative effects of host plant with low nitrogen fertilization on insect herbivores in many cases can be amplified to the higher trophic levels. In the present study, we examined the impact of varying ni...

  6. Effective dominance of resistance of Spodoptera frugiperda to Bt maize and cotton varieties: implications for resistance management

    Science.gov (United States)

    Horikoshi, Renato J.; Bernardi, Daniel; Bernardi, Oderlei; Malaquias, José B.; Okuma, Daniela M.; Miraldo, Leonardo L.; Amaral, Fernando S. de A. e; Omoto, Celso

    2016-01-01

    The resistance of fall armyworm (FAW), Spodoptera frugiperda, has been characterized to some Cry and Vip3A proteins of Bacillus thuringiensis (Bt) expressed in transgenic maize in Brazil. Here we evaluated the effective dominance of resistance based on the survival of neonates from selected Bt-resistant, heterozygous, and susceptible (Sus) strains of FAW on different Bt maize and cotton varieties. High survival of strains resistant to the Cry1F (HX-R), Cry1A.105/Cry2Ab (VT-R) and Cry1A.105/Cry2Ab/Cry1F (PW-R) proteins was detected on Herculex, YieldGard VT PRO and PowerCore maize. Our Vip3A-resistant strain (Vip-R) exhibited high survival on Herculex, Agrisure Viptera and Agrisure Viptera 3 maize. However, the heterozygous from HX-R × Sus, VT-R × Sus, PW-R × Sus and Vip-R × Sus had complete mortality on YieldGard VT PRO, PowerCore, Agrisure Viptera, and Agrisure Viptera 3, whereas the HX-R × Sus and Vip-R × Sus strains survived on Herculex maize. On Bt cotton, the HX-R, VT-R and PW-R strains exhibited high survival on Bollgard II. All resistant strains survived on WideStrike, but only PW-R and Vip-R × Sus survived on TwinLink. Our study provides useful data to aid in the understanding of the effectiveness of the refuge strategy for Insect Resistance Management of Bt plants. PMID:27721425

  7. Insect growth regulatory effects of some extracts and sterols from Myrtillocactus geometrizans (Cactaceae) against Spodoptera frugiperda and Tenebrio molitor.

    Science.gov (United States)

    Céspedes, Carlos L; Salazar, J Rodrigo; Martínez, Mariano; Aranda, Eduardo

    2005-10-01

    A methanol extract from the roots and aerial parts of Myrtillocactus geometrizans (Cactaceae) yielded peniocerol 1, macdougallin 2, and chichipegenin 3. The natural products 1, 2 their mixtures, MeOH and CH(2)Cl(2) extracts showed insecticidal and insect growth regulatory activity against fall armyworm [Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae)], an important insect pest of corn, and [Tenebrio molitor (Coleoptera)], a pest of stored grains in Mexico. The most active compounds were 1, 2, and a mixture (M(2)) of 1 and 2 (6:4). All these extracts, compounds and the mixture had insect growth regulating (IGR) activity between 5.0 and 50.0 ppm and insecticidal effects between 50 and 300 ppm in diets. The extracts were insecticidal to larvae, with lethal doses between 100 and 200 ppm. These compounds appear to have selective effects on the pre-emergence metabolism of Coleoptera, because in all treatments of the larvae of T. molitor, pupation were shortened and this process show precociousness in relation to controls. In contrast to S. frugiperda larvae, onset of pupation was noticeably delayed. Emergence in both cases was drastically diminished. In both pupae and in the few adults that were able to emerge, many deformations were observed. The results of these assays indicated that the compounds were more active than other known natural insect growth inhibitors such as gedunin and methanol extracts of Cedrela salvadorensis and Yucca periculosa. Peniocerol, macdougallin and chichipegenin, as well as mixtures of these substances, may be useful as natural insecticidal agents.

  8. Helicoverpa zea (Lepidoptera: Noctuidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) Responses to Sorghum bicolor (Poales: Poaceae) Tissues From Lowered Lignin Lines.

    Science.gov (United States)

    Dowd, Patrick F; Sattler, Scott E

    2015-01-01

    The presence of lignin within biomass impedes the production of liquid fuels. Plants with altered lignin content and composition are more amenable to lignocellulosic conversion to ethanol and other biofuels but may be more susceptible to insect damage where lignin is an important resistance factor. However, reduced lignin lines of switchgrasses still retained insect resistance in prior studies. Therefore, we hypothesized that sorghum lines with lowered lignin content will also retain insect resistance. Sorghum excised leaves and stalk pith Sorghum bicolor (L.) Moench (Poales: Poaceae) from near isogenic brown midrib (bmr) 6 and 12 mutants lines, which have lowered lignin content and increased lignocellulosic ethanol conversion efficiency, were examined for insect resistance relative to wild-type (normal BTx623). Greenhouse and growth chamber grown plant tissues were fed to first-instar larvae of corn earworms, Helicoverpa zea (Boddie) and fall armyworms Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), two sorghum major pests. Younger bmr leaves had significantly greater feeding damage in some assays than wild-type leaves, but older bmr6 leaves generally had significantly less damage than wild-type leaves. Caterpillars feeding on the bmr6 leaves often weighed significantly less than those feeding on wild-type leaves, especially in the S. frugiperda assays. Larvae fed the pith from bmr stalks had significantly higher mortality compared with those larvae fed on wild-type pith, which suggested that bmr pith was more toxic. Thus, reducing lignin content or changing subunit composition of bioenergy grasses does not necessarily increase their susceptibility to insects and may result in increased resistance, which would contribute to sustainable production.

  9. Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in Four Crop Plants.

    Science.gov (United States)

    Gordy, John W; Leonard, B Rogers; Blouin, David; Davis, Jeffrey A; Stout, Michael J

    2015-01-01

    Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA), benzothiadiazole (BTH), gibberellic acid (GA), harpin, and jasmonic acid (JA) are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith) (FAW) (Lepidoptera: Noctuidae) larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker)], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

  10. Comparative Effectiveness of Potential Elicitors of Plant Resistance against Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae in Four Crop Plants.

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    John W Gordy

    Full Text Available Feeding by insect herbivores activates plant signaling pathways, resulting in the enhanced production of secondary metabolites and other resistance-related traits by injured plants. These traits can reduce insect fitness, deter feeding, and attract beneficial insects. Organic and inorganic chemicals applied as a foliar spray, seed treatment, or soil drench can activate these plant responses. Azelaic acid (AA, benzothiadiazole (BTH, gibberellic acid (GA, harpin, and jasmonic acid (JA are thought to directly mediate plant responses to pathogens and herbivores or to mimic compounds that do. The effects of these potential elicitors on the induction of plant defenses were determined by measuring the weight gains of fall armyworm, Spodoptera frugiperda (J. E. Smith (FAW (Lepidoptera: Noctuidae larvae on four crop plants, cotton, corn, rice, and soybean, treated with the compounds under greenhouse conditions. Treatment with JA consistently reduced growth of FAW reared on treated cotton and soybean. In contrast, FAW fed BTH- and harpin-treated cotton and soybean tissue gained more weight than those fed control leaf tissue, consistent with negative crosstalk between the salicylic acid and JA signaling pathways. No induction or inconsistent induction of resistance was observed in corn and rice. Follow-up experiments showed that the co-application of adjuvants with JA failed to increase the effectiveness of induction by JA and that soybean looper [Chrysodeixis includens (Walker], a relative specialist on legumes, was less affected by JA-induced responses in soybean than was the polyphagous FAW. Overall, the results of these experiments demonstrate that the effectiveness of elicitors as a management tactic will depend strongly on the identities of the crop, the pest, and the elicitor involved.

  11. Proteomics of the 26S proteasome in Spodoptera frugiperda cells infected with the nucleopolyhedrovirus, AcMNPV.

    Science.gov (United States)

    Lyupina, Yulia V; Zatsepina, Olga G; Serebryakova, Marina V; Erokhov, Pavel A; Abaturova, Svetlana B; Kravchuk, Oksana I; Orlova, Olga V; Beljelarskaya, Svetlana N; Lavrov, Andrey I; Sokolova, Olga S; Mikhailov, Victor S

    2016-06-01

    Baculoviruses are large DNA viruses that infect insect species such as Lepidoptera and are used in biotechnology for protein production and in agriculture as insecticides against crop pests. Baculoviruses require activity of host proteasomes for efficient reproduction, but how they control the cellular proteome and interact with the ubiquitin proteasome system (UPS) of infected cells remains unknown. In this report, we analyzed possible changes in the subunit composition of 26S proteasomes of the fall armyworm, Spodoptera frugiperda (Sf9), cells in the course of infection with the Autographa californica multiple nucleopolyhedrovirus (AcMNPV). 26S proteasomes were purified from Sf9 cells by an immune affinity method and subjected to 2D gel electrophoresis followed by MALDI-TOF mass spectrometry and Mascot search in bioinformatics databases. A total of 34 homologues of 26S proteasome subunits of eukaryotic species were identified including 14 subunits of the 20S core particle (7 α and 7 β subunits) and 20 subunits of the 19S regulatory particle (RP). The RP contained homologues of 11 of RPN-type and 6 of RPT-type subunits, 2 deubiquitinating enzymes (UCH-14/UBP6 and UCH-L5/UCH37), and thioredoxin. Similar 2D-gel maps of 26S proteasomes purified from uninfected and AcMNPV-infected cells at 48hpi confirmed the structural integrity of the 26S proteasome in insect cells during baculovirus infection. However, subtle changes in minor forms of some proteasome subunits were detected. A portion of the α5(zeta) cellular pool that presumably was not associated with the proteasome underwent partial proteolysis at a late stage in infection.

  12. Effective dominance of resistance of Spodoptera frugiperda to Bt maize and cotton varieties: implications for resistance management.

    Science.gov (United States)

    Horikoshi, Renato J; Bernardi, Daniel; Bernardi, Oderlei; Malaquias, José B; Okuma, Daniela M; Miraldo, Leonardo L; Amaral, Fernando S de A E; Omoto, Celso

    2016-10-10

    The resistance of fall armyworm (FAW), Spodoptera frugiperda, has been characterized to some Cry and Vip3A proteins of Bacillus thuringiensis (Bt) expressed in transgenic maize in Brazil. Here we evaluated the effective dominance of resistance based on the survival of neonates from selected Bt-resistant, heterozygous, and susceptible (Sus) strains of FAW on different Bt maize and cotton varieties. High survival of strains resistant to the Cry1F (HX-R), Cry1A.105/Cry2Ab (VT-R) and Cry1A.105/Cry2Ab/Cry1F (PW-R) proteins was detected on Herculex, YieldGard VT PRO and PowerCore maize. Our Vip3A-resistant strain (Vip-R) exhibited high survival on Herculex, Agrisure Viptera and Agrisure Viptera 3 maize. However, the heterozygous from HX-R × Sus, VT-R × Sus, PW-R × Sus and Vip-R × Sus had complete mortality on YieldGard VT PRO, PowerCore, Agrisure Viptera, and Agrisure Viptera 3, whereas the HX-R × Sus and Vip-R × Sus strains survived on Herculex maize. On Bt cotton, the HX-R, VT-R and PW-R strains exhibited high survival on Bollgard II. All resistant strains survived on WideStrike, but only PW-R and Vip-R × Sus survived on TwinLink. Our study provides useful data to aid in the understanding of the effectiveness of the refuge strategy for Insect Resistance Management of Bt plants.

  13. Effective dominance of resistance of Spodoptera frugiperda to Bt maize and cotton varieties: implications for resistance management

    Science.gov (United States)

    Horikoshi, Renato J.; Bernardi, Daniel; Bernardi, Oderlei; Malaquias, José B.; Okuma, Daniela M.; Miraldo, Leonardo L.; Amaral, Fernando S. De A. E.; Omoto, Celso

    2016-10-01

    The resistance of fall armyworm (FAW), Spodoptera frugiperda, has been characterized to some Cry and Vip3A proteins of Bacillus thuringiensis (Bt) expressed in transgenic maize in Brazil. Here we evaluated the effective dominance of resistance based on the survival of neonates from selected Bt-resistant, heterozygous, and susceptible (Sus) strains of FAW on different Bt maize and cotton varieties. High survival of strains resistant to the Cry1F (HX-R), Cry1A.105/Cry2Ab (VT-R) and Cry1A.105/Cry2Ab/Cry1F (PW-R) proteins was detected on Herculex, YieldGard VT PRO and PowerCore maize. Our Vip3A-resistant strain (Vip-R) exhibited high survival on Herculex, Agrisure Viptera and Agrisure Viptera 3 maize. However, the heterozygous from HX-R × Sus, VT-R × Sus, PW-R × Sus and Vip-R × Sus had complete mortality on YieldGard VT PRO, PowerCore, Agrisure Viptera, and Agrisure Viptera 3, whereas the HX-R × Sus and Vip-R × Sus strains survived on Herculex maize. On Bt cotton, the HX-R, VT-R and PW-R strains exhibited high survival on Bollgard II. All resistant strains survived on WideStrike, but only PW-R and Vip-R × Sus survived on TwinLink. Our study provides useful data to aid in the understanding of the effectiveness of the refuge strategy for Insect Resistance Management of Bt plants.

  14. Toxicity of the phenolic extract from jabuticabeira (Myrciaria cauliflora (Mart. O. Berg fruit skins on Spodoptera frugiperda

    Directory of Open Access Journals (Sweden)

    Ana Paula C Alves

    2014-04-01

    Full Text Available Fall armyworm, Spodoptera frugiperda J.E. Smith, 1797 (Lepidoptera: Noctuidae is the main pest of maize, besides attacking sorghum and cotton crops. The control of this pest has been accomplished mainly with the use of synthetic insecticides but, due to the growing concern about the environment and food quality, phenolic compounds have shown their potential for the biological control of this insect. Thus, the objective of the present study was to evaluate the efficiency of the extract of jabuticabeira, Myrciaria cauliflora [Mart.] O. Berg (Myrtaceae fruit skin flour in the control of S. frugiperda. Skins of M. cauliflora Sabará genotype were dried at 45 °C in a forced air oven. In order to obtain the extract, 1.0 g flour was mixed with 10 mL acetone: water solution (7:3 v/v. Forty-eight-hour-old S. frugiperda caterpillars were placed in glass tubes with an artificial diet containing the extract at concentrations of 0, 250, 500, 1000, and 2000 mg L-1. The extract, in which the phenolic compounds gallic acid, gallocatechin, catechin, epicatechin, ellagic acid, and salicylic acid were identified at a concentration of 2000 mg L-1, in average, increased mortality rates by 150% in the larval stage, duration of larval stages by 60%, and pupal by 17%, and decreased amount of females by 55%. On the other hand, the extract at 1000 mg L-1 only increased duration of larval period by 24%. It was concluded that the extract is harmful to this insect, probably due to the presence of phenolic compounds.

  15. Spatial analysis of the distribution of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) and losses in maize crop productivity using geo statistics

    Energy Technology Data Exchange (ETDEWEB)

    Farias, Paulo R.S.; Miranda, Vicente S.; Ribeiro, Susane M. [Universidade Federal Rural da Amazonia (UFRA), Belem, PA (Brazil). Inst. de Ciencias Agrarias]. E-mail: paulo.farias@ufra.edu.br; Barbosa, Jose C. [UNESP, Jaboticabal, SP (Brazil). Faculdade de Ciencias Agrarias e Veterinarias. Dept. de Ciencias Exatas; Busoli, Antonio C. [UNESP, Jaboticabal, SP (Brazil). Faculdade de Ciencias Agrarias e Veterinarias. Dept. de Fitossanidade; Overal, William L. [Museu Paraense Emilio Goeldi (MPEG), Belem, PA (Brazil). Coordenacao de Zoologia

    2008-05-15

    The fall armyworm, Spodoptera frugiperda (J.E. Smith), is one of the chief pests of maize in the Americas. The study of its spatial distribution is fundamental for designing correct control strategies, improving sampling methods, determining actual and potential crop losses, and adopting precise agricultural techniques. In Sao Paulo state, Brazil, a maize field was sampled at weekly intervals, from germination through harvest, for caterpillar densities, using quadrates. In each of 200 quadrates, 10 plants were sampled per week. Harvest weights were obtained in the field for each quadrate, and ear diameters and lengths were also sampled (15 ears per quadrate) and used to estimate potential productivity of the quadrate. Geostatistical analyses of caterpillar densities showed greatest ranges for small caterpillars when semivariograms were adjusted for a spherical model that showed greatest fit. As the caterpillars developed in the field, their spatial distribution became increasingly random, as shown by a model adjusted to a straight line, indicating a lack of spatial dependence among samples. Harvest weight and ear length followed the spherical model, indicating the existence of spatial variability of the production parameters in the maize field. Geostatistics shows promise for the application of precise methods in the integrated control of pests. (author)

  16. Spatial analysis of the distribution of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) and losses in maize crop productivity using geostatistics.

    Science.gov (United States)

    Farias, Paulo R S; Barbosa, José C; Busoli, Antonio C; Overal, William L; Miranda, Vicente S; Ribeiro, Susane M

    2008-01-01

    The fall armyworm, Spodoptera frugiperda (J.E. Smith), is one of the chief pests of maize in the Americas. The study of its spatial distribution is fundamental for designing correct control strategies, improving sampling methods, determining actual and potential crop losses, and adopting precise agricultural techniques. In São Paulo state, Brazil, a maize field was sampled at weekly intervals, from germination through harvest, for caterpillar densities, using quadrates. In each of 200 quadrates, 10 plants were sampled per week. Harvest weights were obtained in the field for each quadrate, and ear diameters and lengths were also sampled (15 ears per quadrate) and used to estimate potential productivity of the quadrate. Geostatistical analyses of caterpillar densities showed greatest ranges for small caterpillars when semivariograms were adjusted for a spherical model that showed greatest fit. As the caterpillars developed in the field, their spatial distribution became increasingly random, as shown by a model adjusted to a straight line, indicating a lack of spatial dependence among samples. Harvest weight and ear length followed the spherical model, indicating the existence of spatial variability of the production parameters in the maize field. Geostatistics shows promise for the application of precise methods in the integrated control of pests.

  17. Characterization of an Sf-rhabdovirus-negative Spodoptera frugiperda cell line as an alternative host for recombinant protein production in the baculovirus-insect cell system.

    Science.gov (United States)

    Maghodia, Ajay B; Geisler, Christoph; Jarvis, Donald L

    2016-06-01

    Cell lines derived from the fall armyworm, Spodoptera frugiperda (Sf), are widely used as hosts for recombinant protein production in the baculovirus-insect cell system (BICS). However, it was recently discovered that these cell lines are contaminated with a virus, now known as Sf-rhabdovirus [1]. The detection of this adventitious agent raised a potential safety issue that could adversely impact the BICS as a commercial recombinant protein production platform. Thus, we examined the properties of Sf-RVN, an Sf-rhabdovirus-negative Sf cell line, as a potential alternative host. Nested RT-PCR assays showed Sf-RVN cells had no detectable Sf-rhabdovirus over the course of 60 passages in continuous culture. The general properties of Sf-RVN cells, including their average growth rates, diameters, morphologies, and viabilities after baculovirus infection, were virtually identical to those of Sf9 cells. Baculovirus-infected Sf-RVN and Sf9 cells produced equivalent levels of three recombinant proteins, including an intracellular prokaryotic protein and two secreted eukaryotic glycoproteins, and provided similar N-glycosylation patterns. In fact, except for the absence of Sf-rhabdovirus, the only difference between Sf-RVN and Sf9 cells was SF-RVN produced higher levels of infectious baculovirus progeny. These results show Sf-RVN cells can be used as improved, alternative hosts to circumvent the potential safety hazard associated with the use of Sf-rhabdovirus-contaminated Sf cells for recombinant protein manufacturing with the BICS.

  18. Selection of Annonaceae Species for the Control of Spodoptera frugiperda (Lepidoptera: Noctuidae) and Metabolic Profiling of Duguetia lanceolata Using Nuclear Magnetic Resonance Spectroscopy.

    Science.gov (United States)

    Alves, D S; Machado, A R T; Campos, V A C; Oliveira, D F; Carvalho, G A

    2016-04-01

    This study was performed to investigate the activity of 19 dichloromethane-soluble fractions obtained from the methanolic extracts of 10 Annonaceae species against the fall armyworm, Spodoptera frugiperda (J. E. Smith). The stem bark of Duguetia lanceolata A. St.-Hil. showed the highest insecticidal activity, with a median lethal time (LT50) of 61.4 h and a median lethal concentration (LC50) of 946.5 µg/ml of diet. The dichloromethane-soluble fractions from six D. lanceolata specimens were subjected to evaluation of their activities against S. frugiperda and metabolomic analysis using hydrogen (1H) nuclear magnetic resonance (NMR) spectroscopy. Although all of the samples affected S. frugiperda mortality, their insecticidal activities varied according to the sample used in the experiments. Using partial least squares regression of the results, the D. lanceolata specimens were grouped according to their metabolite profile and insecticidal activity. A detailed analysis via uni- and bidimensional NMR spectroscopy showed that the peaks in the 1H NMR spectra associated with increased insecticidal activity could be attributed to 2,4,5-trimethoxystyrene, which suggests that this substance is involved in the insecticidal activity of the stem bark fraction of D. lanceolata.

  19. cDNA cloning and recombinant expression of the general odorant binding protein Ⅱ from Spodoptera litura

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A cDNA encoding the general odorant binding protein Ⅱ(GOBP Ⅱ) was isolated from the antennae of Spodoptera litura(SlGOBP Ⅱ,GenBank Accession No.EU086371) by homologous cloning and rapid amplification of cDNA ends(RACE).Sequencing and structural analyses revealed that the open reading frame(ORF) of SlGOBP Ⅱ was 489 bp,encoding 162 amino acids with a predicted MW of 18.2 kD and pI of 5.72.SlGOPB Ⅱ shared typical structural features of odorant binding proteins with other insects,including the six conservative cysteine residues.The deduced amino acid sequence of SlGOPB Ⅱ shared significant identity with the GOBP Ⅱ from S.frugiperda and S.exigua.RT-PCR and Northern blot analyses showed that SlGOBP Ⅱ was specifically expressed in the antennae.cDNA encoding SlGOBP Ⅱ was constructed into the pET-32a vector and the recombinant protein was highly expressed in Escherichia coli BL21(DE3) after induction with IPTG.SDS electrophoresis and Western blot analysis confirmed the molecular weight of the recombinant SIGOBPⅡ i.e,32 kD,which has a 6×His tag at the N-terminus.The recombinant SlGOBP Ⅱ was purified by single-step Ni-NTA affinity chromatography and used to raise antiserum in rabbits.ELISA showed that the titer of antiserum was 1:12800,while Western blot analysis showed that the recombinant SlGOBP Ⅱ was recognized as anti-SlGOBP Ⅱ antiserum.

  20. cDNA cloning and recombinant expression of the gen-eral odorant binding protein Ⅱ from Spodoptera litura

    Institute of Scientific and Technical Information of China (English)

    JIN FengLiang; DONG XiaoLin; XU XiaoXia; REN ShunXiang

    2009-01-01

    A cDNA encoding the general odorant binding protein Ⅱ (GOBP Ⅱ) was isolated from the antennae of Spodoptera fitura (SiGOBP Ⅱ, GenBank Accession No. EU086371) by homologous cloning and rapid amplification of cDNA ends (RACE). Sequencing and structural analyses revealed that the open reading frame (ORF) of SIGOBP Ⅱ was 489 bp, encoding 162 amino acids with a predicted MW of 18.2 kD and pl of 5.72. SIGOPB Ⅱ shared typical structural features of odorant binding proteins with other insects, including the six conservative cysteine residues. The deduced amino acid sequence of SIGOPB Ⅱ shared significant identity with the GOBP Ⅱ from S. frugiperda and S. exigua. RT-PCR and Northern blot analyses showed that SIGOBP Ⅱ was specifically expressed in the antennae, cDNA encoding SIGOBP Ⅱ was constructed into the pET-32a vector and the recombinant protein was highly expressed in Es-cherichia coil BL21 (DE3) after induction with IPTG. SDS electrophoresis and Western blot analysis confirmed the molecular weight of the recombinant SIGOBPⅡ i.e, 32 kD, which has a 6xHis tag at the N-terminus. The recombinant SIGOBP U was purified by single-step Ni-NTA affinity chromatography and used to raise antiserum in rabbits. ELISA showed that the titer of antiserum was 1 : 12800, while Western blot analysis showed that the recombinant SIGOBP Ⅱ was recognized as anti-SiGOBP Ⅱ an-tiserum.

  1. Levantamento de Meloidogyne exigua na cultura da seringueira em São José do Rio Claro, MT, Brasil

    Directory of Open Access Journals (Sweden)

    Bernardo Eduardo Roberto de Almeida

    2003-01-01

    Full Text Available Este trabalho foi realizado com o objetivo de efetuar um levantamento da ocorrência de Meloidogyne exigua em seringueira em São José do Rio Claro, MT. Foram amostradas 191 propriedades agrícolas, totalizando cerca de 18.000ha. Os nematóides foram identificados no Laboratório de Nematologia do Departamento de Fitossanidade da FCAV/UNESP, em Jaboticabal, SP. Foram encontrados níveis populacionais de M. exigua entre 0 e 61.824 juvenis/5g de raízes.

  2. Diterpene Constituents of Euphorbia exigua L. and Multidrug Resistance Reversing Activity of the Isolated Diterpenes.

    Science.gov (United States)

    Rédei, Dóra; Boros, Klára; Forgo, Peter; Molnár, Joseph; Kele, Zoltán; Pálinkó, István; Pinke, Gyula; Hohmann, Judit

    2015-08-01

    Phytochemical investigation of the MeOH extract obtained from the aerial parts of the annual weed Euphorbia exigua L. resulted in the isolation of two novel (1, 2) and one known (3) jatrophane diterpenes. Their structures were established by extensive 1D- and 2D-NMR spectroscopy and HR-ESI-MS. The isolated compounds were evaluated for multidrug resistance (MDR) reversing activity on human MDR gene-transfected L5178 mouse lymphoma cells; and all three compounds were found to modulate the intracellular drug accumulation.

  3. Distributional patterns of fall armyworm parasitoids in a corn field and pasture field in Florida

    Science.gov (United States)

    An assessment of parasitoids and their selective patterns among Spodoptera frugiperda corn and rice host strains was performed from August 2008-August 2010 in a corn crop and a grass pasture in northern Florida under different seasonal conditions (spring and fall). Sentinel larvae from our laborator...

  4. Avoidance of crude-oil contaminated sediment by the Australian seastar, Patiriella exigua (Echinodermata: Asteroidea)

    Energy Technology Data Exchange (ETDEWEB)

    Ryder, K. [RMIT University, Victoria (Australia). Department of Biotechnology and Environmental Biology; Temara, A. [RMIT University, Victoria (Australia). Department of Biotechnology and Environmental Biology; Procter and Gamble, Environmental Safety (Belgium); Holdway, D.A. [RMIT University, Victoria (Australia). Department of Biotechnology and Environmental Biology; University of Ontario Institute of Technology, Oshawa, Ont. (Canada). Faculty of Science

    2004-12-01

    This study attempted to determine whether Patiriella exigua, an Australian seastar, could detect and/or avoid oiled sediment when given an equal choice of unoiled sediment. The sediment was spiked once to produce one of three concentrations of oiled sediment used in the test chambers versus unoiled sediment. Behavioral observations were repeated over a 32 day period to test the effects of aging the oiled sediment. Results show that Patiriella exigua was capable of detecting oiled sediment and/or an oiled environment. Seastars avoided oiled sediment, with significantly higher numbers choosing either to reside on the clean sediment (p<0.05) or to travel up the glass sides of the tanks (p<0.0001). Avoidance of oiled sediment increased with increasing sediment oil concentrations. Aging the oiled sediment decreased the oil content of the sediment and increased the number of seastars able to inhabit it (p<0.001). A potential narcotic effect of exposure to oiled sediment was observed. (author)

  5. Association of bioassays and molecular characterization to select new Bacillus thuringiensis isolates effective against Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae); Associacao de bioensaios e caracterizacao molecular para selecao de novos isolados de Bacillus thuringiensis efetivos contra Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

    Energy Technology Data Exchange (ETDEWEB)

    Fatoretto, Julio C.; Sena, Janete A.D.; Lemos, Manoel V.F. [UNESP, Jaboticabal, SP (Brazil). Faculdade de Ciencias Agrarias e Veterinarias. Dept. de Biologia Aplicada a Agropecuaria; Barreto, Marliton R. [Universidade Federal do Mato Grosso (UFMT), Cuiaba, MT (Brazil). Inst. Universitario do Norte Matogrossense (IUNMAT)]. E-mail: mrbarreto@pop.com.br; Junior Boica, Arlindo L. (UNESP), Jaboticabal, SP (Brazil). Faculdade de Ciencias Agrarias e Veterinarias. Dept. de Fitossanidade)

    2007-09-15

    The fall armyworm, Spodoptera frugiperda (J. E. Smith), is one of the main corn pests and Bacillus thuringiensis is important in its control because of its entomopathogenic property. The objective of this study was the molecular characterization of B. thuringiensis isolates for cry1 locus presence and the assessment of the efficiency of these isolates in controlling S. frugiperda caterpillars. Gral-cry1 was used in the PCR analyses to confirm the presence of the cry1 locus in 15 isolates. A 3 x 108 spore/ml suspension bathed the diet used to feed 30 caterpillars per isolate, with three replications. The cry1 locus type genes of the different isolates were identified for five gene subclasses; linear regression analyses were carried out to ascertain possible associations between the presence of an individual cry1 locus gene and high levels of toxicity. All the DNAs amplified with Gral-cry1 presented an amplification product with the expected size. Regarding the levels of insecticide efficiency against the cob worm, 41 isolates presented 100% mortality and 16 presented an index between 70% and 90%. The cry1Ab gene was present in 80 isolates, cryb in 69 isolates, cry1Ac in all the isolates and cryv and cry1E in 93 and 27 isolates, respectively. The values regarding the individual effect of each gene on caterpillar mortality were significant at 1% probability for the cry1Ac and cry1E genes. (author)

  6. Maize toxin degrades peritrophic matrix proteins and stimulates compensatory transcriptome responses in fall armyworm midgut.

    Science.gov (United States)

    Fescemyer, Howard W; Sandoya, Germán V; Gill, Torrence A; Ozkan, Seval; Marden, James H; Luthe, Dawn S

    2013-03-01

    Understanding the molecular mechanisms underlying insect compensatory responses to plant defenses could lead to improved plant resistance to herbivores. The Mp708 inbred line of maize produces the maize insect resistant 1-cysteine protease (Mir1-CP) toxin. Reduced feeding and growth of fall armyworm larvae fed on Mp708 was previously linked to impairment of nutrient utilization and degradation of the midgut (MG) peritrophic matrix (PM) by Mir1-CP. Here we examine the biochemical and transcriptional responses of fall armyworm larvae to Mir1-CP. Insect Intestinal Mucin (IIM) was severely depleted from pure PMs treated in vitro with recombinant Mir1-CP. Larvae fed on Mp708 midwhorls excrete frass largely depleted of IIM. Cracks, fissures and increased porosity previously observed in the PM of larvae fed on Mp708 midwhorls could ensue when Mir1-CP degrades the IIM that cross-links chitin fibrils in the PM. Both targeted and global transcriptome analyses were performed to determine how complete dissolution of the structure and function of the PM is prevented, enabling larvae to continue growing in the presence of Mir1-CP. The MGs from fall armyworm fed on Mp708 upregulate expression of genes encoding proteins involved in PM production as an apparent compensation to replace the disrupted PM structure and restore appropriate counter-current MG gradients. Also, several families of digestive enzymes (endopeptidases, aminopeptidases, lipases, amylase) were more highly expressed in MGs from larvae fed on Mp708 than MGs from larvae fed on diets lacking Mir1-CP (artificial diet, midwhorls from Tx601 or B73 maize). Impaired growth of larvae fed on Mp708 probably results from metabolic costs associated with higher production of PM constituents and digestive enzymes in a compensatory attempt to maintain MG function.

  7. Pheromonal divergence between two strains of Spodoptera frugiperda

    NARCIS (Netherlands)

    Unbehend, M.; Hänniger, S.; Meagher, R.L.; Heckel, D.G.; Groot, A.T.

    2013-01-01

    Spodoptera frugiperda consists of two genetically and behaviorally different strains, the corn- and the rice-strain, which seem to be in the process of sympatric speciation. We investigated the role of strain-specific sexual communication as a prezygotic mating barrier between both strains by analyz

  8. Relação entre a lagarta-do-cartucho e seus agentes de controle biológico natural na produção de milho Relationship between fall armyworm and their natural biological control agents in the maize crop

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Corrêa Figueiredo

    2006-12-01

    Full Text Available Este trabalho teve como objetivo quantificar as perdas na cultura do milho BRS 3123 decorrentes do ataque da lagarta-do-cartucho (Spodoptera frugiperda, na ausência e presença de seus inimigos naturais. Aos 15 dias depois da emergência da planta, foi realizada uma infestação artificial da praga (uma postura por metro quadrado. As lagartas alimentaram-se da planta, sem a interferência de seus inimigos naturais, pela utilização de uma gaiola de proteção (inicial, de dois dias depois da infestação, até uma proteção máxima de 16 dias. O dano da praga, determinado por uma escala de notas de 0 (plantas sem dano a 5 (plantas mortas, foi em média de 4,01, 1,39, 1,09 e 0,93 para o período de proteção da praga de 16, 6, 4 e 2 dias, respectivamente. Na ausência de agentes de controle biológico, o ataque da praga ocasionou perdas na produção de matéria seca de 47,27% e perdas no rendimento de grãos de 54,49%. Os resultados evidenciaram a importância dos inimigos naturais na supressão de lagartas de S. frugiperda na cultura de milho.This work had the objective of quantifying the losses in the maize hybrid BRS 3123 due to the attack of fall armyworm (Spodoptera frugiperda, in the absence or presence of its natural enemies. Fifteen days after the plant emergency, an artificial infestation (one egg mass per square meter was accomplished. The larvae fed on the plant, without the interference of its natural enemies, by using an appropriated protection cage (initial protection for two days after infestation, until a maximum protection period of 16 days. The damage caused by the pest, determined through a visual scale from 0 (plants without damage to 5 (dead plants, was on average, 4.01, 1.39, 1.09 and 0.93 for the pest protection period of 16, 6, 4 and 2 days, respectively. In the absence of the biological control agents, the attack of the pest caused losses of 47.27% in the dry matter production and losses of 54.49% in grain yield. The

  9. Biocontrol of the oriental armyworm, Mythimna separata, by the tachinid fly, Exorista civilis, is synergized by Cry1Ab protoxin

    Science.gov (United States)

    Tritrophic interactions between the oriental armyworm Mythimna separata, its larval tachinid parasite, Exorista civilis, and the Cry1Ab protoxin of Bacillus thrunginenis, were examined using a laboratory-based system. Although M. separata sixth (last) instar mortality increased with increasing Cry1A...

  10. Corn plants treated with jasmonic acid attract more specialist parasiitoids, thereby increasing parasitization of the common armyworm

    NARCIS (Netherlands)

    Ozawa, R.; Shiojiri, K.; Sabelis, M.W.; Arimura, G.-I.; Nishioka, T.; Takabayashi, J.

    2004-01-01

    We investigated whether corn plants treated with jasmonic acid (JA) increases the ability of the parasitic wasp, Cotesia kariyai, to find and control the common armyworm (Mythimna separata) under laboratory conditions. The rank order of attractiveness increased from intact plants treated with distil

  11. Field-Evolved Mode 1 Resistance of the Fall Armyworm to Transgenic Cry1Fa-Expressing Corn Associated with Reduced Cry1Fa Toxin Binding and Midgut Alkaline Phosphatase Expression.

    Science.gov (United States)

    Jakka, Siva R K; Gong, Liang; Hasler, James; Banerjee, Rahul; Sheets, Joel J; Narva, Kenneth; Blanco, Carlos A; Jurat-Fuentes, Juan L

    2015-12-04

    Insecticidal protein genes from the bacterium Bacillus thuringiensis (Bt) are expressed by transgenic Bt crops (Bt crops) for effective and environmentally safe pest control. The development of resistance to these insecticidal proteins is considered the most serious threat to the sustainability of Bt crops. Resistance in fall armyworm (Spodoptera frugiperda) populations from Puerto Rico to transgenic corn producing the Cry1Fa insecticidal protein resulted, for the first time in the United States, in practical resistance, and Bt corn was withdrawn from the local market. In this study, we used a field-collected Cry1Fa corn-resistant strain (456) of S. frugiperda to identify the mechanism responsible for field-evolved resistance. Binding assays detected reduced Cry1Fa, Cry1Ab, and Cry1Ac but not Cry1Ca toxin binding to midgut brush border membrane vesicles (BBMV) from the larvae of strain 456 compared to that from the larvae of a susceptible (Ben) strain. This binding phenotype is descriptive of the mode 1 type of resistance to Bt toxins. A comparison of the transcript levels for putative Cry1 toxin receptor genes identified a significant downregulation (>90%) of a membrane-bound alkaline phosphatase (ALP), which translated to reduced ALP protein levels and a 75% reduction in ALP activity in BBMV from 456 compared to that of Ben larvae. We cloned and heterologously expressed this ALP from susceptible S. frugiperda larvae and demonstrated that it specifically binds with Cry1Fa toxin. This study provides a thorough mechanistic description of field-evolved resistance to a transgenic Bt crop and supports an association between resistance and reduced Cry1Fa toxin binding and levels of a putative Cry1Fa toxin receptor, ALP, in the midguts of S. frugiperda larvae.

  12. Toll recognition signal activates oenocytoid cell lysis via a crosstalk between plasmatocyte-spreading peptide and eicosanoids in response to a fungal infection.

    Science.gov (United States)

    Park, Jung-A; Kim, Yonggyun

    2012-10-01

    Plasmatocyte-spreading peptide (PSP) activates hemocyte-spreading behavior in response to various microbial pathogens. Its homolog, growth-blocking peptide, has several functions that activate immune cells and induce oenocytoid cell lysis (OCL). OCL is required for release of prophenoloxidase from oenocytoids in the beet armyworm, Spodoptera exigua. Injection of PSP to S. exigua larvae significantly induced in vivo OCL and resulted in significant increase of phenoloxidase (PO) activity. A fungal infection induced PSP expression and also significantly increased OCL. RNA interference (RNAi) of PSP expression significantly suppressed OCL induction and subsequently inhibited PO activation. Interestingly, an addition of dexamethasone (a specific phospholipase A₂ inhibitor) inhibited the PSP activity to induce OCL. Toll signal pathway was associated with PSP action on inducing OCL because RNAi of Toll expression suppressed PSP expression and subsequent OCL induction. However, an addition of PSP to the larvae under RNAi of Toll expression rescued the progress of OCL.

  13. Histopathology and the lethal effect of Cry proteins and strains of Bacillus thuringiensis Berliner in Spodoptera frugiperda J.E. Smith Caterpillars (Lepidoptera, Noctuidae

    Directory of Open Access Journals (Sweden)

    N. Knaak

    Full Text Available Among the phytophagous insects which attack crops, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera, Noctuidae is particularly harmful in the initial growth phase of rice plants. As a potential means of controlling this pest, and considering that the entomopathogen Bacillus thuringiensis Berliner demonstrates toxicity due to synthesis of the Cry protein, the present study was undertaken to evaluate this toxic effect of B. thuringiensis thuringiensis 407 (pH 408 and B. thuringiensis kurstaki HD-73 on S. frugiperda. The following method was used. Both bacterial strains were evaluated in vitro in 1st instar S. frugiperda caterpillars, by means of histopathological assays. The Cry1Ab and Cry1Ac proteins, codified by the respective strains of B. thuringiensis, were evaluated in vivo by bioassays of 1st instar S. frugiperda caterpillars in order to determine the Mean Lethal Concentration (LC50. The results of the histopathological analysis of the midget of S. frugiperda caterpillars demonstrate that treatment with the B. thuringiensis thuringiensis strain was more efficient, because the degradations of the microvilosities started 9 hours after treatment application (HAT, while in the B. thuringiensis kurstaki the same effect was noticed only after 12 HAT. Toxicity data of the Cry1Ab and Cry1Ac proteins presented for the target-species LC50 levels of 9.29 and 1.79 μg.cm-2 respectively. The strains and proteins synthesised by B. thuringiensis thuringiensis and B. thuringiensis kurstaki are effective in controlling S. frugiperda, and may be used to produce new biopesticides or the genes may be utilised in the genetic transformation of Oryza sativa L.

  14. F2 screen for resistance to Bacillus thuringiensis Cry2Ab2-maize in field populations of Spodoptera frugiperda (Lepidoptera: Noctuidae) from the southern United States.

    Science.gov (United States)

    Niu, Ying; Qureshi, Jawwad A; Ni, Xinzhi; Head, Graham P; Price, Paula A; Meagher, Robert L; Kerns, David; Levy, Ronnie; Yang, Xiangbing; Huang, Fangneng

    2016-07-01

    The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a target pest of transgenic maize and cotton expressing Bacillus thuringiensis (Bt) proteins in both North and South America. In 2013 and 2014, a total of 215 F2 two-parent families of S. frugiperda were established using single-pair mating of field individuals collected from seven locations in four states of the southern U.S.: Texas, Louisiana, Georgia, and Florida. The objective of the investigation was to detect resistance alleles in field populations to Cry2Ab2, a common Bt protein produced in transgenic maize and cotton. For each F2 family, 128 F2 neonates were screened on leaf tissue of Cry2Ab2 maize plants in the laboratory. A conservative estimate of the frequency of major Cry2Ab2 resistance alleles in S. frugiperda from the four states was 0.0023 with a 95% credibility interval of 0.0003-0.0064. In addition, six families were considered to likely possess minor resistance alleles at a frequency of 0.0082 with a 95% credibility interval of 0.0033-0.0152. One F2 family from Georgia (GA-15) was confirmed to possess a major resistance allele to the Cry2Ab2 protein. Larvae from this family survived well on whole maize plants expressing Cry2Ab2 protein and demonstrated a significant level (>15-fold) of resistance when fed with the same protein incorporated in a meridic diet. The detection of the major resistance allele along with the relatively abundant minor resistance alleles revealed in this study may have important implications for resistance management.

  15. Histopathology and the lethal effect of Cry proteins and strains of Bacillus thuringiensis Berliner in Spodoptera frugiperda J.E. Smith Caterpillars (Lepidoptera, Noctuidae).

    Science.gov (United States)

    Knaak, N; Franz, A R; Santos, G F; Fiuza, L M

    2010-08-01

    Among the phytophagous insects which attack crops, the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera, Noctuidae) is particularly harmful in the initial growth phase of rice plants. As a potential means of controlling this pest, and considering that the entomopathogen Bacillus thuringiensis Berliner demonstrates toxicity due to synthesis of the Cry protein, the present study was undertaken to evaluate this toxic effect of B. thuringiensis thuringiensis 407 (pH 408) and B. thuringiensis kurstaki HD-73 on S. frugiperda. The following method was used. Both bacterial strains were evaluated in vitro in 1st instar S. frugiperda caterpillars, by means of histopathological assays. The Cry1Ab and Cry1Ac proteins, codified by the respective strains of B. thuringiensis, were evaluated in vivo by bioassays of 1st instar S. frugiperda caterpillars in order to determine the Mean Lethal Concentration (LC50). The results of the histopathological analysis of the midget of S. frugiperda caterpillars demonstrate that treatment with the B. thuringiensis thuringiensis strain was more efficient, because the degradations of the microvilosities started 9 hours after treatment application (HAT), while in the B. thuringiensis kurstaki the same effect was noticed only after 12 HAT. Toxicity data of the Cry1Ab and Cry1Ac proteins presented for the target-species LC50 levels of 9.29 and 1.79 microgxcm-2 respectively. The strains and proteins synthesised by B. thuringiensis thuringiensis and B. thuringiensis kurstaki are effective in controlling S. frugiperda, and may be used to produce new biopesticides or the genes may be utilised in the genetic transformation of Oryza sativa L.

  16. Performance and cross-crop resistance of Cry1F-maize selected Spodoptera frugiperda on transgenic Bt cotton: implications for resistance management.

    Science.gov (United States)

    Yang, Fei; Kerns, David L; Brown, Sebe; Kurtz, Ryan; Dennehy, Tim; Braxton, Bo; Head, Graham; Huang, Fangneng

    2016-06-15

    Transgenic crops producing Bacillus thuringiensis (Bt) proteins have become a primary tool in pest management. Due to the intensive use of Bt crops, resistance of the fall armyworm, Spodoptera frugiperda, to Cry1F maize has occurred in Puerto Rico, Brazil, and some areas of the southeastern U.S. The sustainability of Bt crops faces a great challenge because the Cry1F-maize resistant S. frugiperda may also infest other Bt crops in multiple cropping ecosystems. Here we examined the survival and plant injury of a S. frugiperda population selected with Cry1F maize on three single-gene and five pyramided Bt cotton products. Larvae of Cry1F-susceptible (SS), -heterozygous (RS), and -resistant (RR) genotypes of S. frugiperda were all susceptible to the pyramided cotton containing Cry1Ac/Cry2Ab, Cry1Ac/Cry1F/Vip3A, Cry1Ab/Cry2Ae, or Cry1Ab/Cry2Ae/Vip3A, and the single-gene Cry2Ae cotton. Pyramided cotton containing Cry1Ac/Cry1F was effective against SS and RS, but not for RR. These findings show that the Cry1F-maize selected S. frugiperda can cause cross-crop resistance to other Bt crops expressing similar insecticidal proteins. Resistance management and pest management programs that utilize diversify mortality factors must be implemented to ensure the sustainability of Bt crops. This is especially important in areas where resistance to single-gene Bt crops is already widespread.

  17. SPODOBASE : an EST database for the lepidopteran crop pest Spodoptera

    Directory of Open Access Journals (Sweden)

    Sabourault Cécile

    2006-06-01

    Full Text Available Abstract Background The Lepidoptera Spodoptera frugiperda is a pest which causes widespread economic damage on a variety of crop plants. It is also well known through its famous Sf9 cell line which is used for numerous heterologous protein productions. Species of the Spodoptera genus are used as model for pesticide resistance and to study virus host interactions. A genomic approach is now a critical step for further new developments in biology and pathology of these insects, and the results of ESTs sequencing efforts need to be structured into databases providing an integrated set of tools and informations. Description The ESTs from five independent cDNA libraries, prepared from three different S. frugiperda tissues (hemocytes, midgut and fat body and from the Sf9 cell line, are deposited in the database. These tissues were chosen because of their importance in biological processes such as immune response, development and plant/insect interaction. So far, the SPODOBASE contains 29,325 ESTs, which are cleaned and clustered into non-redundant sets (2294 clusters and 6103 singletons. The SPODOBASE is constructed in such a way that other ESTs from S. frugiperda or other species may be added. User can retrieve information using text searches, pre-formatted queries, query assistant or blast searches. Annotation is provided against NCBI, UNIPROT or Bombyx mori ESTs databases, and with GO-Slim vocabulary. Conclusion The SPODOBASE database provides integrated access to expressed sequence tags (EST from the lepidopteran insect Spodoptera frugiperda. It is a publicly available structured database with insect pest sequences which will allow identification of a number of genes and comprehensive cloning of gene families of interest for scientific community. SPODOBASE is available from URL: http://bioweb.ensam.inra.fr/spodobase

  18. Two new bradykinin-related peptides from the venom of the social wasp Protopolybia exigua (Saussure).

    Science.gov (United States)

    Mendes, Maria Anita; Palma, Mario Sergio

    2006-11-01

    Two bradykinin-related peptides (Protopolybiakinin-I and Protopolybiakinin-II) were isolated from the venom of the social wasp Protopolybia exigua by RP-HPLC, and sequenced by Edman degradation method. Peptide sequences of Protopolybiakinin-I and Protopolybiakinin-II were DKNKKPIRVGGRRPPGFTR-OH and DKNKKPIWMAGFPGFTPIR-OH, respectively. Synthetic peptides with identical sequences to the bradykinin-related peptides and their biological functions were characterized. Protopolybiakinin-I caused less potent constriction of the isolated rat ileum muscles than bradykinin (BK). In addition, it caused degranulation of mast cells which was seven times more potent than BK. This peptide causes algesic effects due to the direct activation of B(2)-receptors. Protopolybiakinin-II is not an agonist of rat ileum muscle and had no algesic effects. However, Protopolybiakinin-II was found to be 10 times more potent as a mast cell degranulator than BK. The amino acid sequence of Protopolybiakinin-I is the longest among the known wasp kinins.

  19. Cell expansion-mediated organ growth is affected by mutations in three EXIGUA genes.

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    Silvia Rubio-Díaz

    Full Text Available Organ growth depends on two distinct, yet integrated, processes: cell proliferation and post-mitotic cell expansion. Although the regulatory networks of plant cell proliferation during organ growth have begun to be unveiled, the mechanisms regulating post-mitotic cell growth remain mostly unknown. Here, we report the characterization of three EXIGUA (EXI genes that encode different subunits of the cellulose synthase complex specifically required for secondary cell wall formation. Despite this highly specific role of EXI genes, all the cells within the leaf, even those that do not have secondary walls, display small sizes in the exi mutants. In addition, we found a positive correlation between cell size and the DNA ploidy levels in exi mutant leaves, suggesting that both processes share some regulatory components. Our results are consistent with the hypothesis that the collapsed xylem vessels of the exi mutants hamper water transport throughout the plant, which, in turn, limits the turgor pressure levels required for normal post-mitotic cell expansion during leaf growth.

  20. Cell Expansion-Mediated Organ Growth Is Affected by Mutations in Three EXIGUA Genes

    Science.gov (United States)

    González-Bayón, Rebeca; Muñoz-Viana, Rafael; Borrega, Nero; Mouille, Gregory; Hernández-Romero, Diana; Robles, Pedro; Höfte, Herman; Ponce, María Rosa; Micol, José Luis

    2012-01-01

    Organ growth depends on two distinct, yet integrated, processes: cell proliferation and post-mitotic cell expansion. Although the regulatory networks of plant cell proliferation during organ growth have begun to be unveiled, the mechanisms regulating post-mitotic cell growth remain mostly unknown. Here, we report the characterization of three EXIGUA (EXI) genes that encode different subunits of the cellulose synthase complex specifically required for secondary cell wall formation. Despite this highly specific role of EXI genes, all the cells within the leaf, even those that do not have secondary walls, display small sizes in the exi mutants. In addition, we found a positive correlation between cell size and the DNA ploidy levels in exi mutant leaves, suggesting that both processes share some regulatory components. Our results are consistent with the hypothesis that the collapsed xylem vessels of the exi mutants hamper water transport throughout the plant, which, in turn, limits the turgor pressure levels required for normal post-mitotic cell expansion during leaf growth. PMID:22586475

  1. Endocrine Mechanisms Regulating Post-Diapause Development in the Cabbage Armyworm, Mamestra brassicae.

    Directory of Open Access Journals (Sweden)

    Nobuto Yamada

    Full Text Available Diapause, a programmed developmental arrest at a specific stage, is common in insects and is regulated by hormones. It is well established that in pupal diapause, cessation of ecdysteroid secretion from the prothoracic glands (PGs after pupal ecdysis leads to diapause initiation, while resumption of its secretion induces post-diapause development. However, what regulates the activity of the glands is poorly understood, especially for the glands of diapause-terminated pupae. In the present study, we investigate the mechanisms by which post-diapause development is regulated in the cabbage armyworm Mamestra brassicae. We demonstrate that the brain is necessary for the initiation of post-diapause development and that the factor in the brain responsible for the activation of the PGs is the prothoracicotropic hormone (PTTH. Further, through measuring the hemolymph PTTH titers by time-resolved fluoroimmunoassay, we show that PTTH is actually released into the hemolymph prior to the activation of the PGs. Although its peak titer is much lower than expected, this low concentration of PTTH is most likely still effective to activate the PGs of post-diapause pupae, because the responsiveness to PTTH of the glands at this stage is very high compared to that of nondiapause pupal PGs. These results strongly suggest that in M. brassicae, PTTH serves as a trigger to initiate pupa-adult development after diapause termination by stimulating the PGs to secrete ecdysteroid.

  2. Endocrine Mechanisms Regulating Post-Diapause Development in the Cabbage Armyworm, Mamestra brassicae.

    Science.gov (United States)

    Yamada, Nobuto; Okamoto, Naoki; Kataoka, Hiroshi; Mizoguchi, Akira

    2016-01-01

    Diapause, a programmed developmental arrest at a specific stage, is common in insects and is regulated by hormones. It is well established that in pupal diapause, cessation of ecdysteroid secretion from the prothoracic glands (PGs) after pupal ecdysis leads to diapause initiation, while resumption of its secretion induces post-diapause development. However, what regulates the activity of the glands is poorly understood, especially for the glands of diapause-terminated pupae. In the present study, we investigate the mechanisms by which post-diapause development is regulated in the cabbage armyworm Mamestra brassicae. We demonstrate that the brain is necessary for the initiation of post-diapause development and that the factor in the brain responsible for the activation of the PGs is the prothoracicotropic hormone (PTTH). Further, through measuring the hemolymph PTTH titers by time-resolved fluoroimmunoassay, we show that PTTH is actually released into the hemolymph prior to the activation of the PGs. Although its peak titer is much lower than expected, this low concentration of PTTH is most likely still effective to activate the PGs of post-diapause pupae, because the responsiveness to PTTH of the glands at this stage is very high compared to that of nondiapause pupal PGs. These results strongly suggest that in M. brassicae, PTTH serves as a trigger to initiate pupa-adult development after diapause termination by stimulating the PGs to secrete ecdysteroid.

  3. Susceptibility, mechanisms of response and resistance to Bacillus thuringiensis toxins in Spodoptera spp.

    Science.gov (United States)

    Herrero, Salvador; Bel, Yolanda; Hernández-Martínez, Patricia; Ferré, Juan

    2016-06-01

    Bioinsecticides based on Bacillus thuringiensis have long been used as an alternative to synthetic insecticides to control insect pests. In this review, we focus on insects of the genus Spodoptera, including relevant polyphagous species that are primary and secondary pests of many crops, and how B. thuringiensis toxins can be used for Spodoptera spp. pest management. We summarize the main findings related to susceptibility, midgut binding specificity, mechanisms of response and resistance of this insect genus to B. thuringiensis toxins.

  4. Ruta graveolens Extracts and Metabolites against Spodoptera frugiperda.

    Science.gov (United States)

    Ayil-Gutiérrez, Benjamin A; Villegas-Mendoza, Jesús M; Santes-Hernndez, Zuridai; Paz-González, Alma D; Mireles-Martínez, Maribel; Rosas-García, Ninfa M; Rivera, Gildardo

    2015-11-01

    The biological activity of Ruta graveolens leaf tissue extracts obtained with different solvents (ethyl acetate, ethanol, and water) and metabolites (psoralen, 2- undecanone and rutin) against Spodoptera frugiperda was evaluated. Metabolites levels in extracts were quantified by HPLC and GC. Ethyl acetate and ethanol extracts showed 94% and 78% mortality, respectively. Additionally, psoralen metabolite showed a high mortality as cypermethrin. Metabolite quantification in extracts shows the presence of 2-undecanone (87.9 µmoles mg(-1) DW), psoralen (3.6 µmoles mg(-1) DW) and rutin (0.001 pmoles mg(-1) DW). We suggest that these concentrations of 2-undecanone and psoralen in R. graveolens leaf tissue extracts could be responsible for S. frugiperda mortality.

  5. Palaeoceanographic implications of abundance and mean proloculus diameter of benthic foraminiferal species Epistominella exigua in sub-surface sediments from distal Bay of Bengal fan

    Indian Academy of Sciences (India)

    R Saraswat; R Nigam; Lea Barreto

    2005-10-01

    Temporal variation in abundance and mean proloculus diameter of the benthic foraminiferal species Epistominella exigua has been reconstructed over the last ∼ 50,000 yr BP,from a core collected from the distal Bay of Bengal fan,to assess its potential application in palaeoceanographic reconstruction studies.The down-core variation shows significant change in abundance of E. exigua during the last ∼50,000 yr BP.In view of the present day abundance of this species from areas with strong seasonal organic matter supply, we conclude that at ∼7, ∼22, ∼33 and ∼46 kyr BP, strong seasonality prevailed in the distal Bay of Bengal fan,probably indicating either strong or prolonged north–east monsoon or weakened south–west monsoon.For the first time,a strong correlation is observed in abundance and mean proloculus diameter of E. exigua Based on coherent variation in mean proloculus diameter and abundance,it is postulated that mean proloculus diameter can also be used to infer increased seasonality in organic matter production,thus variation in strength or duration of monsoon.Thus,this study establishes that the down-core variation in the abundance and mean proloculus diameter of Epistominella exigua can be used to infer past climatic variations from the distal Bay of Bengal fan.

  6. Palaeoceanographic implications of abundance and mean proloculus diameter of benthic foraminiferal species Epistominella exigua in sub-surface sediments from distal Bay of Bengal fan

    Digital Repository Service at National Institute of Oceanography (India)

    Saraswat, R.; Nigam, R.; Barreto, L.

    to infer increased seasonality in organic matter production, thus variation in strength or duration of monsoon. Thus, this study establishes that the down-core variation in the abundance and mean proloculus diameter of E. exigua can be used to infer past...

  7. Maize plants sprayed with either jasmonic acid or its precursor, methyl linolenate, attract armyworm parasitoids, but the composition of attractants differs

    NARCIS (Netherlands)

    Ozawa, R.; Shiojiri, K.; Sabelis, M.W.; Takabayashi, J.

    2008-01-01

    Treatment of both uninfested and armyworm-infested maize plants with jasmonic acid (JA) is known to attract the parasitic wasp, Cotesia kariyai Watanabe (Hymenoptera: Braconidae). Here, we show that treatment with a methyl ester of a JA precursor, methyl linolenate (MeLin), also causes maize plants

  8. Effects of the Bax channel on cantharidin induced apoptosis of Spodoptera frugiperda Sf9 cells%Bax通道在斑蝥素诱导草地贪夜蛾Sf9细胞凋亡中的作用

    Institute of Scientific and Technical Information of China (English)

    崔高峰; 张鹏飞; 郝少东; 丁凯; 王进忠; 张志勇

    2015-01-01

    Objectives] To investigate the role of the Bax channel on cantharidin-induced cell apoptosis in lepidopteran insects [Methods] Bax channel blocker was used to determine the roles of mitochondrial membrane potential, succinate dehydrogenase activity in mitochondria, and cell morphology, on apoptosis of Sf9 cells derived from fall the armyworm, Spodoptera frugiperda (J.E. Smith) exposed to cantharidin stress. [Results] The results show that Bax channel blocker can delay the decrease of mitochondrial membrane potential and reduce changes in cell morphology, but fail to stop the decline of succinate dehydrogenase activity, in Sf9 cells after treatment with cantharidin. [Conclusion] Bax related channels play a role in cantharidin-induced changes in mitochondrial membrane potential and destruction of cell morphology. However, the Bax channel does not appear to play a role in the suppression of enzyme activity in mitochondria after cantharidin treatment.%【目的】为明确Bax通道在斑蝥素诱导鳞翅目昆虫细胞凋亡过程中的作用。【方法】本文利用Bax通道抑制法测定了斑蝥素诱导鳞翅目昆虫草地贪夜蛾Spodoptera frugiperda(J. E. Smith)细胞系Sf9细胞凋亡过程中线粒体膜电位、线粒体琥珀酸脱氢酶活性及细胞形态等方面的影响。【结果】 Bax 通道被抑制后,斑蝥素诱导造成的Sf9细胞线粒体膜电位的降低时间延迟,细胞形变率下降,但琥珀酸脱氢酶活性的下降未受影响。【结论】 Bax通道参与了斑蝥素引起的Sf9细胞线粒体膜电位改变和细胞形态变化,而与抑制线粒体有关能量代谢的酶无直接关系。

  9. Synergistic potential of dillapiole-rich essential oil with synthetic pyrethroid insecticides against fall armyworm

    Directory of Open Access Journals (Sweden)

    Murilo Fazolin

    2016-03-01

    Full Text Available ABSTRACT: The objective of this study was to evaluate the synergy and response homogeneity of the Spodoptera frugiperda larvae population to the Piper aduncum essential oil in combination with pyrethroid insecticides (alpha-cypermethrin, beta-cypermethrin, fenpropathrin, and gamma-cyhalothrin compared to piperonylbutoxide (PBO as positive control. Synergism (SF comparisons were obtained using lethal concentration (LC50 and lethal dose (LD50 ratios of insecticides individually and in their respective synergistic combinations with essential oil and PBO. Dose/concentration-mortality slope curves were used to establish relative toxicity increase promoted by synergism. They also determined homogeneity response. Residual contact revealed significant potentiation for commercial insecticides formulated with beta-cypermethrin (SF=9.05-0.5 and fenpropathrin (SF=34.05-49.77 when combined with the P. aduncum essential oil. For topical contact, significant potentiation occurred only for alpha-cypermethrin (SF=7.55-3.68, fenpropathrin (SF=3.37-1.21, and gamma-cyhalothrin (SF=5.79-10.48 insecticides when combined with essential oil. With the exception of fenpropathrin and gamma-cyhalothrin, insecticides synergistic combinations presented homogeneous response by topical as well as residual contact at least with essential oil. The SF significance values ​​of the P. aduncum essential oil combined with alpha-cypermethrin, beta-cypermethrin, fenpropathrin, and gamma-cyhalothrin insecticides indicated potential for this oil to be used as an alternative to PBO.

  10. Scientific Opinion on the pest categorisation of Spodoptera littoralis

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Plant Health (PLH

    2015-01-01

    Full Text Available The Panel on Plant Health undertook a pest categorisation of Spodoptera littoralis (Boisduval for the territory of the European Union (EU. This insect is morphologically very similar to S. litura but the two species occupy very distinct geographical distributions, with only S. littoralis found in Europe and Africa. S. littoralis is established only in the southernmost parts of Europe where winters are not too cold. Long-distance northward migrations occur and the pest can also be transported throughout the EU with plants for planting. S. littoralis is highly polyphagous and it is an important pest of a very wide variety of outdoor vegetable, salad and ornamental crops in southern Europe. Field crops, such as lucerne, can also be affected, and even football pitches can be damaged. Population densities and damage vary considerably from year to year. Outbreaks also occur in protected crops, particularly ornamentals, throughout the EU. A very large number of insecticides are deployed to control this pest, which is resistant to many compounds. Resistance management and successful control of the pest can be obtained with mass trapping, mating disruption and attract-and-kill methods. S. littoralis is listed in Annex IAII and special requirements for S. littoralisare formulated in Annexes IVAI and IVAII of Council Directive 2000/29/EC to regulate the movement of plants for planting of three ornamental genera (Dendranthema, Dianthus and Pelargonium.

  11. A draft genome assembly of the army worm, Spodoptera frugiperda.

    Science.gov (United States)

    Kakumani, Pavan Kumar; Malhotra, Pawan; Mukherjee, Sunil K; Bhatnagar, Raj K

    2014-08-01

    Spodoptera is an agriculturally important pest insect and studies in understanding its biology have been limited by the unavailability of its genome. In the present study, the genomic DNA was sequenced and assembled into 37,243 scaffolds of size, 358 Mb with N50 of 53.7 kb. Based on degree of identity, we could anchor 305 Mb of the genome onto all the 28 chromosomes of Bombyx mori. Repeat elements were identified, which accounts for 20.28% of the total genome. Further, we predicted 11,595 genes, with an average intron length of 726 bp. The genes were annotated and domain analysis revealed that Sf genes share a significant homology and expression pattern with B. mori, despite differences in KOG gene categories and representation of certain protein families. The present study on Sf genome would help in the characterization of cellular pathways to understand its biology and comparative evolutionary studies among lepidopteran family members to help annotate their genomes.

  12. Efeito de indutores de resistência sobre Meloidogyne exigua do cafeeiro Effect of resistance inducers on Meloidogyne exígua of coffee

    Directory of Open Access Journals (Sweden)

    Sônia Maria de Lima Salgado

    2007-08-01

    Full Text Available A possibilidade de manejo de Meloidogyne exigua Goeldi, 1887, pela ativação de mecanismos de defesa no cafeeiro representa uma alternativa potencialmente útil no manejo desse patógeno. Com este trabalho, objetivou-se avaliar a eclosão e mortalidade de juvenis do segundo estádio (J2 de M. exigua na presença de produtos indutores de resistência e avaliar o efeito do acibenzolar-S-metil (ASM, Bion® na indução de resistência do cafeeiro (Coffea arabica L. 'Catuaí- 144' contra M. exigua. A eclosão e mortalidade do J2 foram avaliadas no ASM e ácido salicílico (AS nas dosagens de 0,2; 0,35 e 0,5 g. i. a./L; e no fosfito de potássio (Hortifós® PK e silicato de potássio (Supa-potássio® nas dosagens 5,0; 7,5 e 10,0 mL/L, empregando água e aldicarbe como testemunhas. No segundo ensaio o ASM (0,2 g i.a./L foi aplicado na quantidade de 125 mL por planta de 'Catuaí-144' com um ano de idade, via pulverização foliar e diretamente ao solo aos 7 dias antes da inoculação e aos 2 e 7 dias após a inoculação de aproximadamente 7000 ovos de M. exigua/planta. Foram utilizadas 8 plantas/tratamento/bloco, totalizando 6 tratamentos (3 épocas de aplicação do ASM, testemunhas absoluta e inoculada, em 4 blocos. Aos 90 dias da inoculação, foi feita a avaliação da população final (número de ovos e juvenis de M. exigua, número de galhas, fator de reprodução (população final/população inicial e peso da matéria fresca da raiz. A dosagem dos produtos não influenciou a eclosão e mortalidade dos J2 de M. exigua. Menor eclosão dos J2 de M. exigua ocorreu igualmente no Supa-potássio® e ácido salicílico, enquanto que a eclosão no ASM e na água foi igual (P The parasitism of coffee roots by Meloidogyne exigua Goeldi, 1887, widespread nematode in the main producing regions, can provoke a series of modifications in the normal development of the plant. The induction of resistance for the activation of existing latent mechanisms of

  13. Estádio de adaptação de Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae em hospedeiros alternativos Fitness stage of Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae on alternative hosts

    Directory of Open Access Journals (Sweden)

    Katia Gisele Brasil Boregas

    2013-03-01

    -de-açúcar.The main target pest on maize is the fall armyworm, Spodoptera frugiperda (J.E. Smith, 1797 (Lepidoptera: Noctuidae, which, by their seasonal and geographical distribution is one of the most damaging species in tropical regions of America. The objective was the evaluation of S. frugiperda fitness stage on 17 host plant species, cultivated or wild, most common in the Brazilian agro ecosystem. The plants were cultivated in five planting times, between 2006 and 2008, using corn as standard of comparison. Newly hatched larvae of S. frugiperda were individualized and confined in 50 mL plastic pots, where they were fed with new leaves of each host. Food was replaced every other day with fresh leaf sections of each plant host. Four biological variables were evaluated and used to estimate the Fitness Index (FI. The initial larval survival ranged from 100% on maize to 46% on rice. The larval period ranged from 12.6 days on maize to 27.1 days on bahiagrass. The pupa biomass ranged from 173.1 mg on burgrass to 294.2 mg on maize. The fitness index, calculated on the base of S. frugiperda fitness on each host ranged from 17.43 on maize cultivated at time I to 1.46 on sugarcane cultivated at time III. In order to correct the time effect on S. frugiperda fitness stage on hosts, the Relative Fitness Index (RFI was calculated in relation to maize crop. According to this index, the host rank to S. frugiperda fitness was in decreasing order: grain sorghum, johnson grass, millet, guinea grass, peanut, bread grass, surinam grass, green amaranth, wheat, soybean, cotton, bean, rice, burgrass, bahiagrass and sugarcane.

  14. Effects of bacillus thuringiensis transgenic corn on corn earworm and fall armyworm (Lepidoptera: Noctuidae) densities.

    Science.gov (United States)

    Chilcutt, Charles F; Odvody, Gary N; Correa, J Carlos; Remmers, Jeff

    2007-04-01

    We examined 17 pairs of near-isogenic hybrids of Bacillus thuringiensis (Bt) (176, Mon810, and Bt11) and non-Bt corn, Zea mays L., to examine the effects of Bt on larval densities of Helicoverpa zea (Boddie) and Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) during 2 yr. During ear formation, instar densities of H. zea and S. frugiperda were recorded for each hybrid. We found that H. zea first, second, and fifth instar densities were each affected by Mon810 and Bt11 Bt corn but not by 176 corn. Surprisingly, first and second instars were found in higher numbers on ears of Mon810 and Bt11 corn than on non-Bt corn. Densities of third and fourth instars were equal on Bt and non-Bt hybrids, whereas densities of fifth instars were lower on Bt plants. S. frugiperda larval densities were only affected during 1 yr when second, and fourth to sixth instars were lower on ears of Mon810 and Bt11 hybrids compared with their non-Bt counterparts. Two likely explanations for early instar H. zea densities being higher on Bt corn than non-Bt corn are that (1) Bt toxins delay development, creating a greater abundance of early instars that eventually die, and (2) reduced survival of H. zea to later instars on Bt corn decreased the normal asymmetric cannibalism or H. zea-S. frugiperda intraguild predation of late instars on early instars. Either explanation could explain why differences between Bt and non-Bt plants were greater for H. zea than S. frugiperda, because H. zea is more strongly affected by Bt toxins and more cannibalistic.

  15. 不同温度和浓度下核型多角体病毒对甜菜夜蛾的致病力%Effect of Concentration and Temperature on Pathogenicity of Spodoptera exigua Nuclear Polyhedrosis Virus

    Institute of Scientific and Technical Information of China (English)

    徐彩霞; 韩日畴

    2010-01-01

    于室内测定了不同温度下核型多角体病毒对甜菜夜蛾的致病力和不同浓度核型多角体病毒对甜菜夜蛾致病力的影响.结果表明,在(25±1)℃条件下.病毒浓度为1×107 PIBa/mL、1×106 PIBdmL、1×105 PIBs/mL、1×104 PIBs/mL、1×103 PIBs/mL时,甜菜夜蛾3龄幼虫感染10 d后的累计死亡率分别为83.3%.83.3%,86.7%,90.3%,96.7%,但处理间差异不显著.温度显著影响甜菜夜蛾病毒的致病力.病毒浓度为1×106 PIBs/mL时,在30℃和35℃下,甜菜夜蛾3龄幼虫感染10 d后的累计死亡率均为96.7%.在15℃下仅为53.3%.在35℃,30℃,25℃,20℃.15℃下,LT50分别为5.0 d,4.8 d,5.4 d,8.8 d,13.7 d.

  16. Study on Bacillus thuringiensis "CZE99985" with High Toxin to Spodoptera exigua%对甜菜夜蛾高毒苏云金芽孢杆菌菌株CZE99985的研究

    Institute of Scientific and Technical Information of China (English)

    陈在佴; 吴继星; 张志刚

    2004-01-01

    分离到对甜菜夜蛾高毒的苏云金芽孢杆菌一个菌株CZE99985,并进行了研究.该菌具有鲇泽亚种的典型特征,属血清型H7,生理生化特性与鲇泽亚种略有差异.但对甜菜夜蛾的毒力大大高于对照菌株.

  17. 甜菜夜蛾对氰戊菊酯和顺式氯氰菊酯的抗性机理%Resistance mechanisms of Spodoptera exigua(Hübner)to fenvalerate and alpha-cypermethrin

    Institute of Scientific and Technical Information of China (English)

    兰亦全; 赵士熙

    2010-01-01

    通过对活体增效作用进行测定和生化分析,探讨了甜菜夜蛾对氰戊菊酯和顺式氯氰菊酯的抗性机理.结果表明:增效醚(PBO)、增效磷(SV1)、磷酸三苯酯(TPP)和顺丁烯二酸二乙酯(DEM)对甜菜夜蛾抗氰戊菊酯品系(Fen-R)和敏感品系(S)的增效倍数之比分别为10.2、7.8、12.5和1.1,对抗顺式氯氰菊酯品系(Cyp-R)和敏感品系(S)的增效倍数之比分别为21.6、15.5、8.6和1.2.PBO、SV_1和TPP对氰戊菊酯和顺式氯氰菊酯均有显著增效作用,表明多功能氧化酶和羧酸酯酶均参与了甜菜夜蛾对氰戊菊酯和顺式氯氰菊酯的抗性.Fen-R品系和Cyp-R品系4龄幼虫羧酸酯酶的活性分别是S品系的1.9和2.2倍,而谷胱甘肽-S-转移酶活性与S品系差异不显著,表明羧酸酯酶活性的提高是甜菜夜蛾对氰戊菊酯和顺式氯氰菊酯产生抗性的重要因为,谷胱甘肽-S-转移酶与两种药剂的抗性无关.Fen-R品系和Cyp-R品系的Na-K-ATPase活性与S品系均无显著差异,但在相同浓度下氰戊菊酯和顺式氯氰菊酯对S品系Na-K-ATPase的抑制作用显著高于抗性品系,表明抗性品系Na-K-ATPase对杀虫剂的敏感性已明显降低.

  18. Vip3A, a novel Bacillus thuringiensis vegetative insecticidal protein with a wide spectrum of activities against lepidopteran insects.

    Science.gov (United States)

    Estruch, J J; Warren, G W; Mullins, M A; Nye, G J; Craig, J A; Koziel, M G

    1996-05-28

    A novel vegetative insecticidal gene, vip3A(a), whose gene product shows activity against lepidopteran insect larvae including black cutworm (Agrotis ipsilon), fall armyworm (Spodoptera frugiperda), beet armyworm (Spodoptera exigua), tobacco budworm (Heliothis virescens), and corn earworm (Helicoverpa zea) has been isolated from Bacillus thuringiensis strain AB88. VIP3-insecticidal gene homologues have been detected in approximately 15% of Bacillus strains analyzed. The sequence of the vip3A(b) gene, a homologue of vip3A(a) isolated from B. thuringiensis strain AB424 is also reported. Vip3A(a) and (b) proteins confer upon Escherichia coli insecticidal activity against the lepidopteran insect larvae mentioned above. The sequence of the gene predicts a 791-amino acid (88.5 kDa) protein that contains no homology with known proteins. Vip3A insecticidal proteins are secreted without N-terminal processing. Unlike the B. thuringiensis 5-endotoxins, whose expression is restricted to sporulation, Vip3A insecticidal proteins are expressed in the vegetative stage of growth starting at mid-log phase as well as during sporulation. Vip3A represents a novel class of proteins insecticidal to lepidopteran insect larvae.

  19. Midgut proteins released by microapocrine secretion in Spodoptera frugiperda.

    Science.gov (United States)

    Silva, Walciane; Cardoso, Christiane; Ribeiro, Alberto F; Terra, Walter R; Ferreira, Clélia

    2013-01-01

    Microapocrine vesicles bud from the lepidopteran midgut microvilli as double membrane vesicles. To identify the proteins secreted by this process, antibodies raised against isolated microapocrine vesicles from Spodoptera frugiperda were used for screening a midgut cDNA expression library. Positive clones were sequenced, assembled and N blasted against S. frugiperda sequences obtained by pyrosequencing midgut mRNA. This procedure led to the extension of microapocrine sequences that were annotated. A similar procedure was used to identify midgut microvillar proteins that necessarily are part of the microapocrine vesicle. Forty-eight proteins were associated with microvillar membranes. They pertain to 8 functional groups: digestive enzymes, peritrophic membrane, protection, transporters, receptors, secretory machinery, cytoskeleton and signaling, and unknown. Twenty-eight proteins are putatively secreted by microapocrine secretion. Most of them are digestive enzymes, but the list also includes proteins involved in protection and in peritrophic membrane formation. Among the identified digestive enzymes, aminopeptidases are typically microvillar and group into the classes 1, 2, 3, 5, and 6. There are two amylases secreted by microapocrine secretion: one is a digestive enzyme and the other is a transporter-like amylase with no clear function. One lipase has a predicted transmembrane loop, whereas the others are supposed to be secreted by microapocrine secretion and be digestive. Trypsin is membrane bound and is delivered by microapocrine secretion, but has no predicted features to bind membranes. It may remain bound through the signal peptide till be delivered into the midgut lumen. Proteins supposed to be involved in the microapocrine secretory machinery were: calmodulin, annexin, myosin 7a, and gelsolin 1. Their putative roles are discussed, but more research is necessary to settle this subject.

  20. Pheromonal divergence between two strains of Spodoptera frugiperda.

    Science.gov (United States)

    Unbehend, Melanie; Hänniger, Sabine; Meagher, Robert L; Heckel, David G; Groot, Astrid T

    2013-03-01

    Spodoptera frugiperda consists of two genetically and behaviorally different strains, the corn- and the rice-strain, which seem to be in the process of sympatric speciation. We investigated the role of strain-specific sexual communication as a prezygotic mating barrier between both strains by analyzing strain-specific variation in female pheromone composition of laboratory and field strains, and also male attraction in wind tunnel and field experiments. Laboratory-reared and field-collected females from Florida exhibited strain-specific differences in their relative amount of (Z)-7-dodecenyl acetate (Z7-12:OAc) and (Z)-9-dodecenyl acetate (Z9-12:OAc). In wind tunnel assays, we did not find strain-specific attraction of males to females. However, in field experiments in Florida, we observed some differential attraction to synthetic pheromone blends. In a corn field, the corn-strain blend attracted more males of both strains than the rice-strain blend, but both blends were equally attractive in a grass field. Thus, habitat-specific volatiles seemed to influence male attraction to pheromones. In dose-response experiments, corn-strain males were more attracted to 2 % Z7-12:OAc than other doses tested, while rice-strain males were attracted to a broader range of Z7-12:OAc (2-10 %). The attraction of corn-strain males to the lowest dose of Z7-12:OAc corresponds to the production of this compound by females; corn-strain females produced significantly smaller amounts of Z7-12:OAc than rice-strain females. Although corn-strain individuals are more restricted in their production of and response to pheromones than rice-strain individuals, it seems that differences in sexual communication between corn- and rice-strain individuals are not strong enough to cause assortative mating.

  1. QSAR analysis on Spodoptera litura antifeedant activities for flavone derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Duchowicz, Pablo R., E-mail: pabloducho@gmail.com [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas INIFTA (UNLP, CCT La Plata-CONICET), Diag. 113 y 64, Sucursal 4, C.C. 16, 1900 La Plata (Argentina); Goodarzi, Mohammad [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas INIFTA (UNLP, CCT La Plata-CONICET), Diag. 113 y 64, Sucursal 4, C.C. 16, 1900 La Plata (Argentina); Ocsachoque, Marco A. [Centro de Investigacion y Desarrollo en Ciencias Aplicadas ' Dr. J. J. Ronco' (CINDECA), Departamento de Quimica, Facultad de Ciencias Exactas, UNLP-CONICET. Calle 47 No 257, B1900AJK La Plata (Argentina); Romanelli, Gustavo P. [Centro de Investigacion y Desarrollo en Ciencias Aplicadas ' Dr. J. J. Ronco' (CINDECA), Departamento de Quimica, Facultad de Ciencias Exactas, UNLP-CONICET. Calle 47 No 257, B1900AJK La Plata (Argentina); Catedra de Quimica Organica, Facultad de Ciencias Agrarias y Forestales, UNLP. Calles 60 y 119, B1904AAN La Plata (Argentina); Ortiz, Erlinda del V. [Facultad de Tecnologia y Ciencias Aplicadas, Universidad Nacional de Catamarca, Av. Maximio Victoria 55, (4700), Catamarca (Argentina); Autino, Juan C.; Bennardi, Daniel O.; Ruiz, Diego M. [Catedra de Quimica Organica, Facultad de Ciencias Agrarias y Forestales, UNLP. Calles 60 y 119, B1904AAN La Plata (Argentina); Castro, Eduardo A. [Instituto de Investigaciones Fisicoquimicas Teoricas y Aplicadas INIFTA (UNLP, CCT La Plata-CONICET), Diag. 113 y 64, Sucursal 4, C.C. 16, 1900 La Plata (Argentina)

    2009-12-20

    We establish useful models that relate experimentally measured biological activities of compounds to their molecular structure. The pED{sub 50} feeding inhibition on Spodoptera litura species exhibited by aurones, chromones, 3-coumarones and flavones is analyzed in this work through the hypothesis encompassed in the Quantitative Structure-Activity Relationships (QSAR) Theory. This constitutes a first necessary computationally based step during the design of more bio-friendly repellents that could lead to insights for improving the insecticidal activities of the investigated compounds. After optimizing the molecular structure of each furane and pyrane benzoderivative with the semiempirical molecular orbitals method PM3, more than a thousand of constitutional, topological, geometrical and electronic descriptors are calculated and multiparametric linear regression models are established on the antifeedant potencies. The feature selection method employed in this study is the Replacement Method, which has proven to be successful in previous analyzes. We establish the QSAR both for the complete molecular set of compounds and also for each chemical class, so that acceptably describing the variation of the inhibitory activities from the knowledge of their structure and thus achieving useful predictive results. The main interest of developing trustful QSAR models is that these enable the prediction of compounds having no experimentally measured activities for any reason. Therefore, the structure-activity relationships are further employed for investigating the antifeedant activity on previously synthesized 2-,7-substituted benzopyranes, which do not pose any measured values on the biological expression. One of them, 2-({alpha}-naphtyl)-4H-1-benzopyran-4-one, results in a promising structure to be experimentally analyzed as it has predicted pED{sub 50} = 1.162.

  2. Insecticidal activity of Trichilia claussenii (Meliaceae) fruits against Spodoptera frugiperda; Atividade inseticida dos frutos de Trichilia claussenii (Meliaceae) sobre Spodoptera frugiperda

    Energy Technology Data Exchange (ETDEWEB)

    Nebo, Liliane; Matos, Andrea Pereira; Vieira, Paulo Cezar; Fernandes, Joao Batista; Silva, Maria Fatima das Gracas Fernandes da, E-mail: paulo@dq.ufscar.b [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica; Rodrigues, Ricardo Ribeiro [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Ciencias Biologicas

    2010-07-01

    An evaluation of the insecticidal activity of the fruits extracts of Trichilia claussenii was carried out and the methanol extract revealed to have strong insecticidal activity. The fractionation of methanol extract of T. claussenii seeds bioassay-guided against Spodoptera frugiperda has led to the identification of the {omega}-phenylalkyl and alkenyl fatty acids as active compounds in this extract. The structures of the compounds were proposed by spectroscopic analysis and comparison with literature data. (author)

  3. Caracterização do Baculovirus spodoptera quanto as variações de pH e temperatura

    OpenAIRE

    SOUZA, Wesley Botelho

    2015-01-01

    A redução da produção de milho pode chegar a 73% em condições de ataque elevado de Spodoptera frugiperda, sua principal praga. Para o combate à lagarta do cartucho, foi desenvolvido um biopesticida em pó passível de produção em escala industrial para ser utilizado pelo agricultor sendo esse produto a base de cepas de Baculovirus spodoptera. Em 2006, pesquisadores da EMBRAPA Milho e Sorgo isolaram uma cepa de Baculovirus spodoptera que não rompe os tecidos da lagarta após sua morte (isolado 6 ...

  4. Host association of Spodoptera frugiperda (Lepidoptera: Noctuidae) corn and rice strains in Argentina, Brazil and Paraguay

    NARCIS (Netherlands)

    Juárez, M.L.; Murua, M.G.; García, M.G.; Ontivero, M.; Vera, M.T.; Vilardi, J.C.; Groot, A.T.; Castagnaro, A.P.; Gastaminza, G.; Willink, E.

    2012-01-01

    Spodoptera frugiperda (J.E. Smith) is composed of two genetically distinct strains, the so-called corn strain and the rice strain. Whether the two strains differ in their host use is unclear, because laboratory experiments have not been able to show consistent host performance or preference differen

  5. Laboratory and field evaluations for efficacy of a fast-killing baculovirus isolate from Spodoptera frugiperda

    Science.gov (United States)

    Three biopesticide parameters were evaluated for a fast-killing isolate (3AP2) Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) and a wild-type isolate (Sf3) of the same baculovirus. Both isolates were evaluated for virus production using in vivo methods, for speed of kill based on bioas...

  6. The effect of sub-lethal doses of Azadirachta indica (Meliaceae oil on the midgut of Spodoptera frugiperda (Lepidoptera, Noctuidae Efeito de doses subletais do óleo de Azadirachta indica (Meliaceae no mesêntero de Spodoptera frugiperda (J. E. Smith (Lepidoptera, Noctuidae

    Directory of Open Access Journals (Sweden)

    Antonia Railda Roel

    2010-01-01

    Full Text Available The fall armyworm, Spodoptera frugiperda, is one of the major field pests for maize production. It is mainly controlled by means of synthetic, and more recently by resistant cultivar of maize expressing Bt toxins. The neem tree, Azadirachta indica, is a plant that can potentially control insects with the advantage of being food and environmental safe. The aim of this study was to assess the effect of neem oil on the development and survival of S. frugiperda caterpillars by assessing histological alterations caused on their midgut. Newly hatched caterpillars were submitted to three neem oil concentrations: 0.006; 0.05; 0.4%, which were added to their artificial diet. Ten 3rd instar caterpillars, taken from each treatment, were submitted to histological analysis. The alimentary canals from the specimens were fixed in Baker for 12 hours, desiccated and diaphanized in alcohol/xylol (1:1 and xylol. After placing the samples in paraffin, they were sliced in 8 µm sections and stained with hematoxylin-eosin stain. The neem oil added to the diet of S. frugiperda caused total mortality at dose of 0.4% whilst still in the first instars, prolonged the larval and pupal stages, and reduced the pupal weight. Histo-physiological alterations such as degeneration of the epithelial lining of the midgut and in the peritrophic matrix were found at all concentrations of neem oil.A lagarta-do-cartucho, Spodoptera frugiperda, é a mais importante praga da cultura do milho. Esta é usualmente, controlada por inseticidas sintéticos e mais atualmente por meio de variedades resistentes de milho com a toxina Bt. O nim Azadirachta indica é planta com potencial no controle de insetos, que possui as vantagens de segurança alimentar e ambiental. Objetivou-se com este estudo avaliar o efeito do óleo do nim no desenvolvimento e sobrevivência de lagartas de S. frugiperda em decorrência das alterações no mesêntero. As lagartas recém nascidas foram submetidas a tr

  7. Distribución temporal y espacial de poblaciones larvarias de Spodoptera frugiperda (Smith (Lep.: Noctuidae en diferentes hospederos en provincias del norte de la Argentina Spatial and temporal distribution of Spodoptera frugiperda (Smith (Lep.: Noctuidae larval populations on different host plants in northern Argentina provinces

    Directory of Open Access Journals (Sweden)

    M. Gabriela Murúa

    Full Text Available Para estudiar la distribución temporal y espacial de larvas del "cogollero del maíz" Spodoptera frugiperda en diferentes plantas hospederas, se realizaron muestreos sistemáticos desde el año 2004 al 2007 en diferentes asociaciones de cultivos en las provincias de Tucumán, Salta y Santiago del Estero. Se consideró "asociación de cultivos" a una zona donde coexistían simultáneamente (en tiempo y espacio más de dos cultivos colindantes. Los cultivos monitoreados fueron maíz, sorgo granífero, alfalfa, caña de azúcar, soja, trigo, cártamo, garbanzo y malezas. En cada uno se muestrearon cinco puntos al azar de 1 m² y se revisaron las plantas, recolectándose las posturas y/o larvas presentes. Se encontraron 3620 larvas. La mayor cantidad se recolectó durante los meses del verano en las tres campañas monitoreadas en todas las provincias. Su presencia estuvo relacionada con la aparición de los cultivos estivales como el maíz y el sorgo granífero, en todas las provincias. La mayor cantidad de larvas se obtuvieron en maíz (2894, independientemente de los otros cultivos que formaban parte de la asociación. Siguiendo en orden de importancia, los otros hospederos con larvas fueron: sorgo granífero (272, alfalfa (125 y malezas (282. En base al número de larvas encontradas, la soja, trigo y caña de azúcar, cultivos que estuvieron presentes en casi todas las asociaciones, no son hospederos preferenciales de esta especie.In order to study the spatial and temporal distribution of fall armyworm Spodoptera frugiperda larval populations on different host plants, systematic samplings were made from 2004 to 2007 in different crop associations in the provinces of Tucumán, Salta and Santiago del Estero. A zone where more than two adjacent crops coexisted simultaneously (in time and space was considered a crop association. Sampled crops were corn, sorghum, alfalfa, sugarcane, soybean, wheat, safflower, chickpea and weeds. Five one

  8. The impact of domestication on resistance to two generalist herbivores across 29 independent domestication events.

    Science.gov (United States)

    Turcotte, Martin M; Turley, Nash E; Johnson, Marc T J

    2014-11-01

    The domestication of crops is among the most important innovations in human history. Here, we test the hypothesis that cultivation and artificial selection for increased productivity of crops reduced plant defenses against herbivores. We compared the performance of two economically important generalist herbivores - the leaf-chewing beet armyworm (Spodoptera exigua) and the phloem-feeding green peach aphid (Myzus persicae) - across 29 crop species and their closely related wild relatives. We also measured putative morphological and chemical defensive traits and correlated them with herbivore performance. We show that, on average, domestication significantly reduced resistance to S. exigua, but not M. persicae, and that most independent domestication events did not cause differences in resistance to either herbivore. In addition, we found that multiple plant traits predicted resistance to S. exigua and M. persicae, and that domestication frequently altered the strength and direction of correlations between these traits and herbivore performance. Our results show that domestication can alter plant defenses, but does not cause strong allocation tradeoffs as predicted by plant defense theory. These results have important implications for understanding the evolutionary ecology of species interactions and for the search for potential resistance traits to be targeted in crop breeding.

  9. Population structure of Spodoptera frugiperda maize and rice host forms in South America: are they host strains?

    NARCIS (Netherlands)

    Juárez, M.L.; Schöfl, G.; Vera, M.T.; Vilardi, J.C.; Murúa, M.G.; Willink, E.; Hänniger, S.; Heckel, D.G.; Groot, A.T.

    2014-01-01

    Determining which factors contribute to the formation and maintenance of genetic divergence to evaluate their relative importance as a cause of biological differentiation is among the major challenges in evolutionary biology. In Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) two host strains

  10. Structural and biological characterization of three novel mastoparan peptides from the venom of the neotropical social wasp Protopolybia exigua (Saussure).

    Science.gov (United States)

    Mendes, Maria Anita; de Souza, Bibiana Monson; Palma, Mario Sergio

    2005-01-01

    The venom of the Neotropical social wasp Protopolybia exigua(Saussure) was fractionated by RP-HPLC resulting in the elution of 20 fractions. The homogeneity of the preparations were checked out by using ESI-MS analysis and the fractions 15, 17 and 19 (eluted at the most hydrophobic conditions) were enough pure to be sequenced by Edman degradation chemistry, resulting in the following sequences: Protopolybia MPI I-N-W-L-K-L-G-K-K-V-S-A-I-L-NH2 Protopolybia-MP II I-N-W-K-A-I-I-E-A-A-K-Q-A-L-NH2 Protopolybia-MP III I-N-W-L-K-L-G-K-A-V-I-D-A-L-NH2 All the peptides were manually synthesized on-solid phase and functionally characterized. Protopolybia-MP I is a hemolytic mastoparan, probably acting on mast cells by assembling in plasma membrane, resulting in pore formation; meanwhile, the peptides Protopolybia-MP II and -MP III were characterized as a non-hemolytic mast cell degranulator toxins, which apparently act by virtue of their binding to G-protein receptor, activating the mast cell degranulation.

  11. Biology and thermal requirements of Spodoptera cosmioides (Walk.) (Lepidoptera: Noctuidae)

    Energy Technology Data Exchange (ETDEWEB)

    Bavaresco, Alvimar [EPAGRI, Estacao Experimetal de Canoinhas, SC (Brazil)]. E-mail: alvimarbavaresco@bol.com.br; Garcia, Mauro S.; Gruetzmacher, Anderson D.; Foresti, Josemar; Ringenberg, Rudiney [Universidade Federal de Pelotas (UFPel), RS (Brazil). Dept. de Fitossanidade

    2002-01-15

    The biology of Spodoptera cosmioides (Walk.) was studied under different temperatures and its thermal requirements were determined, aiming to aid the rearing of this insect in the laboratory. Embryonic and post-embryonic periods were evaluated at seven different temperatures (14, 18, 22, 25, 28, 30 and 32 deg C) under environmental chamber conditions, with 14h photophase. The caterpillars were reared on an artificial diet containing white bean, soybean meal, yeast extract, wheat germ and powder milk as source of protein. The extent of the embryonic period decreased with the increase of temperature within the 14 deg C to 25 deg C temperature range, remaining constant between 28 deg C and 32 deg C. For the other phases (caterpillar, pre-pupa and pupa) an inverse relationship between temperature and duration was observed within the 14 deg C to 30 deg C temperature range, extending to 32 deg C for pupae. Duration of pupal phase for males was larger than for females resulting in asynchronous adult emergence. The temperature thresholds for the embryonic, larval, pre-pupal, pupal periods and total cycle were 9.34 deg C, 11.65 deg C, 9.65 deg C, 11.08 deg C and 11.23 deg C, with thermal constants of 62,73 degree-days (DD), 254.61DD, 33.42DD, 177.55DD and 525.11DD, respectively. Evaluating the pupal phase alone, the threshold temperatures were 11.25 deg C for males and 10.81deg C for females, with thermal constants of 188.26DD for males and 165.47DD for females. For total cycle, the threshold temperature and the thermal constant for males were 11.28 deg C and 535.85DD, whereas for females the same variables had values of 11.15 deg C and 513.17DD. So, the most adequate temperature for the development of S. cosmioides is within the range of 25 deg C and 28 deg C, where 9.6 to 11.7 generations of the insect can be annually obtained, in laboratory conditions. (author)

  12. Resistência do cafeeiro a nematóides: I - Testes em progênies e híbridos, para Meloidogyne exigua Coffee breeding for resistance to Meloidogyne exigua: I - Screening test using arabica progenies and interespecific hybrids

    Directory of Open Access Journals (Sweden)

    L. C. Fazuoli

    1977-01-01

    Full Text Available Procurou-se identificar fontes de resistência ao nematóide Meloidogyne exígua em cafeeiros derivados de híbridos interespecíficos e em progênies de café arábica oriundas da Etiópia, em experimentos estabelecidos em duas localidades. A infestação foi feita por dois processos usados com freqüência nesse tipo de trabalho. As avaliações do grau de ataque foram feitas quatro e 12 meses após a infestação, em Campinas e Ribeirão Preto, respectivamente, adotando-se escala variando de zero, para ausência de galhas, a cinco pontos para grande intensidade de ataque. Verificou-se que a leitura feita aos quatro meses é tão eficiente quanto aos 12 meses, indicando a possibilidade de abreviar consideravelmente a duração dessas avaliações. Notou-se, no experimento de Ribeirão Preto, uma redução de aproximadamente 8% no crescimento das mudas infestadas e verificou-se, também, uma redução de 11,5% e 12% nos pesos verde e seco das plantas, devido ao ataque do nematóide. De 1.692 plantas examinadas nos dois experimentos, selecionaram-se 106 (6,3%, caracterizadas pela ausência de galhas. As populações derivadas dos híbridos entre Coffea arabica e C. canephora revelaram-se mais promissoras, contribuindo com maior número de plantas resistentes. As plantas do experimento instalado em Campinas foram inoculadas também com a raça II de Hemileia vastatrix para o estudo da resistência conjunta aos dois patógenos. Essas seleções, em número de 38, representam valioso material para o programa de melhoramento do cafeeiro.Two coffee screening tests were undertaken in order to find out sources of resistance to the nematode M. exigua. Arabica progenies from Ethiopia origin and advanced popu-lations derived from interspecific crosses (Coffea arabica x C. canephora and C. arabica x C. dewevrei were evaluated. A five point scale (0 point to the roots without galls and 5 points to severely attacked roots was used for determination of the

  13. Desenvolvimento do predador Podisus nigrispinus alimentado com Spodoptera frugiperda e Tenebrio molitor Development of the predator Podisus nigrispinus fed on Spodoptera frugiperda and Tenebrio molitor

    OpenAIRE

    Harley Nonato de Oliveira; Dirceu Pratissoli; Eder Pin Pedruzzi; Marcelo Curitiba Espindula

    2004-01-01

    Ninfas de Podisus nigrispinus (Heteroptera: Pentatomidae) têm sido criadas em laboratório com larvas de Tenebrio molitor L. (Coleoptera: Tenebrionidae). No entanto, não existem relatos sobre a predação, no campo ou em laboratório, de P. nigrispinus em Spodoptera frugiperda (Lepidoptera: Noctuidae), uma das principais pragas de inúmeras culturas no Brasil. Este trabalho teve o objetivo de avaliar o desenvolvimento ninfal e características reprodutivas do percevejo predador P. nigrispinus em la...

  14. Interaction between Telenomus remus and Trichogramma pretiosum in the management of Spodoptera spp.

    Directory of Open Access Journals (Sweden)

    Maria Mirmes Paiva Goulart

    2011-03-01

    Full Text Available Interaction betweeen Telenomus remus and Trichogramma pretiosum in the management of Spodoptera spp. The use of egg parasitoids is a promising strategy for Integrated Pest Management (IPM, but different species of parasitoids have greater or lesser control efficiency, depending on the pest species. Recently, not only Anticarsia gemmatalis and Pseudoplusia includens but also Spodoptera cosmioides and S. eridania have been among the key Lepidoptera larvae attacking soybeans. This study evaluated the combination of Telenomus remus and Trichogramma pretiosum for parasitism of eggs of the Spodoptera complex, for better control efficiency and broader spectrum of action among the key pests of soybeans. The experiment was carried out under controlled environmental conditions (25 ± 2ºC; 70 ± 10% RH; and 14 h photophase in a completely randomized experimental design with seven treatments and 10 replicates with S. frugiperda, S. cosmioides and S. eridania eggs. Each replicate consisted of one egg mass of each Spodoptera species, with approximately 100 eggs offered to the parasitoids. The treatments were: 1 10 females of T. pretiosum; 2 nine females of T. pretiosum and one female of T. remus; 3 eight females of T. pretiosum and two females of T. remus; 4 seven females of T. pretiosum and three females of T. remus; 5 six females of T. pretiosum and four females of T. remus; 6 five females of T. pretiosum and five females of T. remus, and 7 10 females of T. remus. The parameter evaluated was the percentage of parasitized eggs. Results showed that treatments combining both parasitoid species with only 1 T. remus for each 9 T. pretiosum (10% and only 2 T. remus for each 8 T. pretiosum (20% were enough to significantly increase the parasitism observed on eggs of S. cosmioides and S. frugiperda, respectively. This association of T. pretiosum and T. remus in different proportions is very promising for biological control in IPM programs because it provides wide

  15. Atividade inseticida dos frutos de Trichilia claussenii (Meliaceae sobre Spodoptera frugiperda

    Directory of Open Access Journals (Sweden)

    Liliane Nebo

    2010-01-01

    Full Text Available An evaluation of the insecticidal activity of the fruits extracts of Trichilia claussenii was carried out and the methanol extract revealed to have strong insecticidal activity. The fractionation of methanol extract of T. claussenii seeds bioassay-guided against Spodoptera frugiperda has led to the identification of the ω-phenylalkyl and alkenyl fatty acids as active compounds in this extract. The structures of the compounds were proposed by spectroscopic analysis and comparison with literature data.

  16. Identification and characteristics of microRNAs from army worm, Spodoptera frugiperda cell line Sf21.

    Science.gov (United States)

    Kakumani, Pavan Kumar; Chinnappan, Mahendran; Singh, Ashok K; Malhotra, Pawan; Mukherjee, Sunil K; Bhatnagar, Raj K

    2015-01-01

    microRNAs play important regulatory role in all intrinsic cellular functions. Amongst lepidopteran insects, miRNAs from only Bombyx mori have been studied extensively with a little focus on Spodoptera sp. In the present study, we identified a total of 226 miRNAs from Spodoptera frugiperda cell line Sf21. Of the total, 116 miRNAs were well conserved within other insects, like B. mori, Drosophila melanogaster and Tribolium castenum while the remaining 110 miRNAs were identified as novel based on comparative analysis with the insect miRNA data set. Landscape distribution analysis based on Sf21 genome assembly revealed clustering of few novel miRNAs. A total of 5 miRNA clusters were identified and the largest one encodes 5 miRNA genes. In addition, 12 miRNAs were validated using northern blot analysis and putative functional role assignment for 6 Sf miRNAs was investigated by examining their relative abundance at different developmental stages of Spodoptera litura and body parts of 6th instar larvae. Further, we identified a total of 809 potential target genes with GO terms for selected miRNAs, involved in different metabolic and signalling pathways of the insect. The newly identified miRNAs greatly enrich the repertoire of insect miRNAs and analysis of expression profiles reveal their involvement at various steps of biochemical pathways of the army worm.

  17. Isolation of Araguspongine M, a New Stereoisomer of an Araguspongine/Xestospongin alkaloid, and Dopamine from the Marine Sponge Neopetrosia exigua Collected in Palau

    Directory of Open Access Journals (Sweden)

    Xinsheng Yao

    2004-11-01

    Full Text Available Abstract: A new stereoisomer of an araguspongine/xestospongin alkaloid, named araguspongine M (1, has been isolated together with 12 known compounds, araguspongines B (2 and D (3, dopamine, three galactosyl diacylglycerols, 24-methyl cholesterol, 5,6-dihydrocholesterol, β-sitosterol, and three 5α,8α-epidioxy sterols (11–13, from the marine sponge Neopetrosia exigua (formerly Xestospongia exigua collected in Palau. The structure of 1 was assigned on the basis of its spectral data analysis. This is the first report on the isolation of dopamine from a marine sponge. This compound may be produced by an endosymbiotic Synechococcus-like cyanobacterium. Compounds 1–3 and 11–13 showed cytotoxicity against HL-60 at IC50’s of 5.5, 5.5, 5.9, 22.4, 9.5, and 9.6 μM, respectively. The possible biosynthesis origin of the isolated metabolites is discussed.

  18. Cell line-specific accumulation of the baculovirus non-hr origin of DNA replication in infected insect cells

    NARCIS (Netherlands)

    Pijlman, G.P.; Vermeesch, A.M.G.; Vlak, J.M.

    2003-01-01

    Successive Viral passage of Spodoptera exigua multicapsid nucleopolyhedrovirus (SeMNPV) in the S. exigua cell line Se301 leads to the rapid accumulation of the non-hr origin of DNA replication (ori) as large concatemers. Passage of SeMNPV in two other S. exigua cell lines, SeUCR1 and SeIZD2109, did

  19. Stereoselective synthesis of 2α-Chloropicropodophyllotoxins and insecticidal activity of their esters against oriental armyworm, Mythimna separata walker.

    Science.gov (United States)

    Fan, Lingling; Guo, Yong; Zhi, Xiaoyan; Yu, Xiang; Xu, Hui

    2014-04-30

    As part of ongoing efforts to discover new natural-product-based insecticidal agents, in the present study, an efficient method for the stereoselective α-chlorination at the C-2 position of 2'(2',6')-(di)halogenopodophyllotoxin derivatives was first developed. Subsequently, a series of novel esters of 2α-chloro-2'(2',6')-(di)halogenopicropodophyllotoxin with modified C, D, and E rings of podophyllotoxin were smoothly obtained. Finally, all of the title compounds were tested against the pre-third-instar larvae of oriental armyworm (Mythimna separata Walker) at 1 mg/mL. It was found that besides their 2'-halogen-substituted E ring, the stereoselective α-chlorination at the C-2 position of 2'(2',6')-(di)halogenopodophyllotoxins was also related to the chlorination reagents. Especially 2α-chloro-4α-(benzoyl)oxy-2'-chloropicropodophyllotoxin (6e) and 2α-chloro-4α-(2-chlorophenylacyl)oxy-2'-bromopicropodophyllotoxin (8f) showed the most potent insecticidal activities, with final mortality rates of >60%. For 4α-(alkylacyl)oxy derivatives of 2α-chloro-2'(2',6')-(di)halogenopicropodophyllotoxin, the effect of the length of their side chain at the C-4 position of podophyllotoxin skeleton on the insecticidal activity was not very obvious. For 4α-(arylacyl)oxy derivatives of 2α-chloro-2'-chloro/bromopicropodophyllotoxin, an electronic effect of the substituents on their phenyl ring at the C-4 position of podophyllotoxin skeleton on the insecticidal activity was observed.

  20. Effect of the aqueous extracts of the seeds of Talisia esculenta and Sapindus saponaria on fall armyworm

    Directory of Open Access Journals (Sweden)

    Wander Laizo dos Santos

    2008-04-01

    Full Text Available The effect of aqueous extracts of Talisia esculenta (T.E. and Sapindus saponaria (S.S., were evaluated on the development and mortality of 8-14th day-life Spodoptera frugiperda, an important pest of maize. Corn leaves were dipped in the aqueous extracts (1% w/v and offered as food to the caterpillars. The treated corn leaves with the extracts caused larval mortality (26.71%/T.E.; 63.3%/S.S. and also showed effect on the larval weight (237.50 mg/T.E.; 86.65 mg/S.S. when compared with the control (11.3% and 293.45 mg, mortality and larval weight, respectively. The electrophoresis with gelatin (0.1% showed two very clear white areas (trypsin activity in the caterpillars midgut of all the treatments. Only the caterpillar treated with S. saponaria presented significant differences, showing trypsin activity (10.59%. Sapindus saponaria appeared better than Talisia esculenta and showed good potential to be used as control agent for S. frugiperda.Este estudo procurou avaliar o potencial inseticida dos extratos aquosos de sementes de Talisia esculenta (St. Hil. Radlk (Pitombal e Sapindus saponaria L. (Saboneteira, ambas da família Sapindaceae, sobre Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae, importante praga da lavoura de milho. As folhas de milho foram imersas nos tratamentos com extratos aquosos (1% p/v e oferecidas como alimento para as lagartas. Os resultados do período larval tais como mortalidade e peso médio foram respectivamente: para S. saponaria 63,15%, 86,65 mg; para T. esculenta 26,71%, 237,50 mg e para o controle 11,3%, 293,45 mg. A eletroforese com gelatina 0,1% mostrou duas regiões brancas muito nítidas (atividade tríptica no intestino médio das lagartas de todos os tratamentos. Somente as lagartas do tratamento S. saponaria, apresentaram diferenças significativas, com uma atividade tríptica 10,59% menor.

  1. Occurrence Characteristics and Comprehensive Treatment Techniques of Wheat Armyworm%小麦粘虫的发生特点与综合治理技术

    Institute of Scientific and Technical Information of China (English)

    陈金安

    2014-01-01

    为了有效地控制小麦粘虫的发生和危害,采用田间系统调查的方法对小麦粘虫的发生特点进行了调查,在此基础上进行了小麦粘虫综合治理技术和不同生物药剂对小麦粘虫幼虫的控制效果研究。结果表明:该虫在孝感市北部地区1年发生4~5代,以幼虫或蛹在麦田土中、稻桩和杂草堆等处越冬;第1代卵孵化盛期在3月下旬至4月上旬,为幼虫最重危害代。综合防治措施以农业防治和生态防治为主,重视保护和利用本地天敌,加强稻草把及糖醋诱剂诱杀成虫,推广使用生物药剂防治,控制使用化学防治的小麦粘虫综合治理策略。生物药剂对小麦粘虫幼虫的控制效果最好的是60 g/L乙基多杀菌素 SC 2000倍液,药后7 d校正防效达95.96%;其次是2.0%阿维菌素 EC 2000倍液,校正防效为95.12%;20%三唑磷 EC 1000倍液的持效性较差,校正防效仅为78.72%;其余3种生物药剂的校正防效均超过89%。%To effectively control the occurrence and hazard of the wheat armyworm,a field system investigation was conducted to explore the occurrence characteristics of wheat armyworm,and based on this the control effects of comprehensive treatment techniques and different biological insecticides.The results showed that this worn existed in the north of Xiaogan City for 4~5 generations,and passed the winter when it is in the generation of larva or insect pupa in wheat field soil,rice stub,a mass of weeds or other places.The first generation egg hatched in late March to early April,this generation of larvae was of the most hazard.Through the study on comprehensive treatment techniques of wheat armyworm,the authors put forward to control agricultural and ecological prevention,protection and pay much attention on local natural enemy,strengthen the straw and sweet and sour attractant for adults worms.At the same time,we should promote the use of bio

  2. Desenvolvimento do predador Podisus nigrispinus alimentado com Spodoptera frugiperda e Tenebrio molitor Development of the predator Podisus nigrispinus fed on Spodoptera frugiperda and Tenebrio molitor

    Directory of Open Access Journals (Sweden)

    Harley Nonato de Oliveira

    2004-10-01

    Full Text Available Ninfas de Podisus nigrispinus (Heteroptera: Pentatomidae têm sido criadas em laboratório com larvas de Tenebrio molitor L. (Coleoptera: Tenebrionidae. No entanto, não existem relatos sobre a predação, no campo ou em laboratório, de P. nigrispinus em Spodoptera frugiperda (Lepidoptera: Noctuidae, uma das principais pragas de inúmeras culturas no Brasil. Este trabalho teve o objetivo de avaliar o desenvolvimento ninfal e características reprodutivas do percevejo predador P. nigrispinus em lagartas de S. frugiperda e em larvas de T. molitor, em laboratório. A presa S. frugiperda proporcionou ao predador menor longevidade, maior produção e viabilidade de ovos do que as larvas de T. molitor. Esses resultados demonstram que a lagarta S. frugiperda melhora as características reprodutivas de P. nigrispinus, de forma que a sua utilização como presa alternativa pode servir para incrementar a produção massal desse inimigo natural.Nymphys of Podisus nigrispinus (Heteroptera: Pentatomidae have been reared on Tenebrio molitor L. (Coleoptera: Tenebrionidae, in laboratory conditions. However, there are no reports on P. nigrispinus predation, in field or laboratory, on Spodoptera frugiperda (Lepidoptera: Noctuidae, one of the most damaging pests in crops in Brazil. This research had the objective to evaluate nymphal development and reproductive characteristics of the predator P. nigrispinus when reared on caterpillars of S. frugiperda and on larvae of T. molitor, in laboratory conditions. S. frugiperda provided a smaller longevity, higher egg production and viability to predator than T. molitor. The nutricional quality of this caterpillar improves the reproductive characteristics of the predator, so that its utilization as factitious host can increase mass production of this natural enemy.

  3. Insecticidal crystal proteins from native Bacillus thuringiensis: numerical analysis and biological activity against Spodoptera frugiperda.

    Science.gov (United States)

    Alvarez, Analía; Pera, Licia M; Loto, Flavia; Virla, Eduardo G; Baigori, Mario D

    2009-01-01

    Fourteen strains of Bacillus thuringiensis collected from both larvae showing disease symptoms and soil samples in northwest Argentina were characterized by insecticidal activity against Spodoptera frugiperda. First instar larvae and protein profile SDS-PAGE analysis of whole cell proteins not only allowed the differentiation of native Bacillus thuringiensis but also revealed the possibility of applying protein profile analysis in classification of toxicity patterns. Cluster analysis showed that there were two main groups. Interestingly, one of them only contained the most pathogenic native strains. The biomass-bound protease activity of native pathogenic isolates and the reference strain Bt 4D1 is also reported.

  4. Ovicidal activity of Atalantia monophylla (L) Correa against Spodoptera litura Fab. (Lepidoptera: Noctuidae)

    OpenAIRE

    Kathirvelu Baskar; Chellaiah Muthu; Gnanaprakasam Antony Raj; Selvadurai Kingsley; Savarimuthu Ignacimuthu

    2012-01-01

    Objective: To evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura). Methods: Hexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0% and 0.5% for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC50 and LC90 were calculat...

  5. Protozoosis caused by Vairimorpha necatrix (Microsporia, Nosematidae in larvae of Spodoptera frugiperda (Lepidoptera, Noctuidae

    Directory of Open Access Journals (Sweden)

    Prafulbala N. Patel

    1988-01-01

    Full Text Available Vairimorpha necatrix was detected among laboratory cultured and field collected Spodoptera frugiperda larvae. Weak infections were not always fatal. In the case of fatal infections among diseased larvae, white patches were formed by agglomerations of adipose tissue beneath the transparent integument. The mid-gut of S. frugiperda larvae presented the first site of histological alterations caused by V. necatrix. The migration of the pathogen, probably occured in the form of agglomerations, from the epithelial cells to the body cavity. Adipose tissue appears to be the principal site for the pathogen development. The nerve ganglia, muscle fibres and epidermis also presented histological alterations due to the pathogen propagation.

  6. Repellent and insecticide activity of Pelargonium x hortorum against Spodoptera littoralis (Boisd.).

    Science.gov (United States)

    Farag, Mohamed; Ahmed, Mohamed H M; Yousef, Heba; El-Badawey, Samy S; Abd El-Ghany, Melegi A; Abdel-Rahman, Adel A H

    2012-01-01

    Insecticide and repellent activity of an acetone extract and oil from fresh leaves of Pelargonium x hortorum (cv. Orangesonne) were evaluated against the 2nd and 4th instar larvae of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae). The oil showed medium toxicity against the 2nd instar and low toxicity against the 4th instar larvae, while the extract showed high significant toxicity at all concentrations tested against the two instars. On the other hand, both oil and extract exhibited highly significant repellency against the two tested instars. Volatile constituents of the oil were also identified by GC-MS analysis.

  7. Desenvolvimento do predador Podisus nigrispinus alimentado com Spodoptera frugiperda e Tenebrio molitor.

    OpenAIRE

    Oliveira,Harley Nonato de; Pratissoli, Dirceu; Pedruzzi,Eder Pin; Espindula,Marcelo Curitiba

    2004-01-01

    Ninfas de Podisus nigrispinus (Heteroptera: Pentatomidae) têm sido criadas em laboratório com larvas de Tenebrio molitor L. (Coleoptera: Tenebrionidae). No entanto, não existem relatos sobre a predação, no campo ou em laboratório, de P. nigrispinus em Spodoptera frugiperda (Lepidoptera: Noctuidae), uma das principais pragas de inúmeras culturas no Brasil. Este trabalho teve o objetivo de avaliar o desenvolvimento ninfal e características reprodutivas do percevejo predador P. nigrispinus em la...

  8. INSECTICIDAL ACTIVITY OF AERIAL PARTS OF SYNEDRELLA NODIFLORA GAERTN (COMPOSITAE ON SPODOPTERA LITURA (FAB.

    Directory of Open Access Journals (Sweden)

    J MARTIN RATHI

    2006-12-01

    Full Text Available Spodoptera litura (Fabricius is the most serious pest of many cultivated and non-cultivated crops and it developed resistance against many synthetic pesticides. The impact of a Compositae annual weed, Synedrella nodifl ora Gaertn. solvent extracts on the fourth instar larvae of S. litura has been evaluated by leaf dip method. The LD50 results revealed that methanol extract is the most toxic to the pest followed by benzene and chloroform, petroleum ether (400 – 600 C and water. Qualitative phytochemical analysis has also been performed.

  9. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures

    Science.gov (United States)

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this cou...

  10. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures

    NARCIS (Netherlands)

    Unbehend, M.; Hänniger, S.; Vásquez, G.M.; Juárez, M.L.; Reisig, D.; McNeil, J.N.; Meagher, R.L.; Jenkins, D.A.; Heckel, D.G.; Groot, A.T.

    2014-01-01

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this cou

  11. Chasing sympatric speciation: The relative importance and genetic basis of prezygotic isolation barriers in diverging populations of Spodoptera frugiperda

    NARCIS (Netherlands)

    Hänniger, S.

    2015-01-01

    This thesis investigates the mechanisms underlying three prezygotic isolation barriers between the corn- and the rice-strain of the noctuid moth Spodoptera frugiperda to determine possible interactions between these isolation barriers and their relative importance for sympatric speciation. First, we

  12. Augmenting Sulfur Metabolism and Herbivore Defense in Arabidopsis by Bacterial Volatile Signaling

    Directory of Open Access Journals (Sweden)

    Mina eAziz

    2016-04-01

    Full Text Available Sulfur is an element necessary for the life cycle of higher plants. Its assimilation and reduction into essential biomolecules are pivotal factors determining a plant’s growth and vigor as well as resistance to environmental stress. While certain soil microbes can enhance ion solubility via chelating agents or oxidation, microbial regulation of plant-sulfur assimilation has not been reported. With an increasing understanding that soil microbes can activate growth and stress tolerance in plants via chemical signaling, the question arises as to whether such beneficial bacteria also regulate sulfur assimilation. Here we report a previously unidentified mechanism by which the growth-promoting rhizobacterium Bacillus amyloliquefaciens (GB03 transcriptionally activates genes responsible for sulfur assimilation, increasing sulfur uptake and accumulation in Arabidopsis. Transcripts encoding for sulfur-rich aliphatic and indolic glucosinolates are also GB03 induced. As a result, GB03-exposed plants with elevated glucosinolates exhibit greater protection against the generalist herbivore, Spodoptera exigua (beet armyworm. In contrast, a previously-characterized glucosinolate mutant compromised in the production of both aliphatic and indolic glucosinolates is also compromised in terms of GB03-induced protection against insect herbivory. As with in vitro studies, soil-grown plants show enhanced glucosinolate accumulation and protection against beet armyworm feeding with GB03 exposure. These results demonstrate the potential of microbes to enhance plant sulfur assimilation and emphasize the sophisticated integration of microbial signaling in plant defense.

  13. Insecticidal activity of residual Bt protein at the second trophic level

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Measurements were taken of Bt protein expressed in the leaves of transgenic cotton (Gossypium hirsutum) transformed with a synthesized Bt (Bacillus thuringiensis) cry1A gene and its persistent level in larval bodies and faeces of a non-targeted insect pest, beet armyworm (Spodoptera exigua). We performed enzyme linked immunosorbent assays (ELISA) and bioassays using neonate larvae of cotton bollworm (Helicoverpa armigera) to detect the insecticidal activity of residual Bt protein at the second trophic level. The results showed that Bt protein content in functional leaves was different at various developmental stages and was different among plants at the same stage. Even though Bt protein concentration in the larval bodies and faeces decreased 97.5%-99% compared to that found in cotton leaves subsequently fed to beet armyworm larvae, it still had a lethal effect on neonate cotton bollworm larvae. Therefore, Bt protein present at the second trophic level had insecticidal activity. This result is important in understanding and predicting the effect of transgenic plants on nontarget organisms.

  14. Synthesis and Insecticidal Activity of Novel Camptothecin Derivatives Containing Analogs of Chrysanthemic Acid Moieties

    Institute of Scientific and Technical Information of China (English)

    DENG Li; ZHANG Lan; CAO Li-dong; XIE Ru-liang; ZHANG Yan-ning; HE Wei-zhi; JIANG Hong-yun

    2014-01-01

    Creating high-efifcient and environment-friendly pesticides is very important to produce the pollution free agriculture food and maintain the balance of the survival environmental of the human being. According to reports, camptothecin (CPT) and its derivatives are now being explored as a class of botanical insecticide in agriculture due to its novel mode of action. In order to improve the insecticidal activity of CPT, ten novel camptothecin (1) and 10-hydroxycamptothecin (2) derivatives (1a, 1b, 1c, 1d, 1e;2a, 2b, 2c, 2d, 2e) were designed and synthesized via esteriifcation with analogs of chrysanthemic acid, which have outstanding insecticidal activity. The results showed that compound 2a exhibited potent antifeeding effect and the best contact toxicity among the target compounds against the third-instar larvae of beet armyworm, Spodoptera exigua Hübner. Compound 2a was also found to be the most effective cytotoxic compound to the tested insect cell lines, IOZCAS-Spex-II, which were established from the fat bodies of S. exigua. It was proposed that the 10-hydroxyl group in the camptothecin derivatives is a key factor for the antifeeding activity of a compound. The nature of the substituents was considered the major factor in determining the insecticidal activity of these compounds.

  15. Synthesis and Insecticidal Activity of Spinosyns with C9-O-Benzyl Bioisosteres in Place of the 2',3',4'-Tri-O-methyl Rhamnose.

    Science.gov (United States)

    Oliver, M Paige; Crouse, Gary D; Demeter, David A; Sparks, Thomas C

    2015-06-17

    The spinosyns are fermentation-derived natural products active against a wide range of insect pests. They are structurally complex, consisting of two sugars (forosamine and rhamnose) coupled to a macrocyclic tetracycle. Removal of the rhamnose sugar results in a >100-fold reduction in insecticidal activity. C9-O-benzyl analogues of spinosyn D were synthesized to determine if the 2',3',4'-tri-O-methyl rhamnose moiety could be replaced with a simpler, synthetic bioisostere. Insecticidal activity was evaluated against larvae of Spodoptera exigua (beet armyworm) and Helicoverpa zea (corn earworm). Whereas most analogues were far less active than spinosyn D, a few of the C9-O-benzyl analogues, such as 4-CN, 4-Cl, 2-isopropyl, and 3,5-diOMe, were within 3-15 times the activity of spinosyn D for larvae of S. exigua and H. zea. Thus, although not yet quite as effective, synthetic bioisosteres can substitute for the naturally occurring 2',3',4'-tri-O-methyl rhamnose moiety.

  16. Bacillus thuringiensis Cry1Ia10 and Vip3Aa protein interactions and their toxicity in Spodoptera spp. (Lepidoptera).

    Science.gov (United States)

    Bergamasco, V B; Mendes, D R P; Fernandes, O A; Desidério, J A; Lemos, M V F

    2013-02-01

    The polyphagous pests belonging to the genus Spodoptera are considered to be among the most important causes of damage and are widely distributed throughout the Americas'. Due to the extensive use of genetically modified plants containing Bacillus thuringiensis genes that code for insecticidal proteins, resistant insects may arise. To prevent the development of resistance, pyramided plants, which express multiple insecticidal proteins that act through distinct mode of actions, can be used. This study analyzed the mechanisms of action for the proteins Cry1Ia10 and Vip3Aa on neonatal Spodoptera frugiperda, Spodoptera albula, Spodoptera eridania and Spodoptera cosmioides larvae. The interactions of these toxins with receptors on the intestinal epithelial membrane were also analyzed by binding biotinylated toxins to brush border membrane vesicles (BBMVs) from the intestines of these insects. A putative receptor of approximately 65 kDa was found by ligand blotting in all of these species. In vitro competition assays using biotinylated proteins have indicated that Vip3Aa and Cry1Ia10 do not compete for the same receptor for S. frugiperda, S. albula and S. cosmioides and that Vip3Aa was more efficient than Cry1Ia10 when tested individually, by bioassays. A synergistic effect of the toxins in S. frugiperda, S. albula and S. cosmioides was observed when they were combined. However, in S. eridania, Cry1Ia10 and Vip3Aa might compete for the same receptor and through bioassays Cry1Ia10 was more efficient than Vip3Aa and showed an antagonistic effect when the proteins were combined. These results suggest that using these genes to develop pyramided plants may not prove effective in preventing the development of resistance in S. eridiana.

  17. Toxicity and physiological effect of quercetin on generalist herbivore, Spodoptera litura Fab. and a non-target earthworm Eisenia fetida Savigny

    Science.gov (United States)

    A novel flavonoid, quercetin, was isolated from Euphorbia hirta L., a medicinal plant using chromatography techniques including: Thin-layer chromatography, Column chromatography, Nuclear magnetic resonance spectroscopy. Toxicity to larval of Spodoptera litura analyze pupal weight, survival rate, fec...

  18. Target and non-target toxicity of botanical insecticide derived from Couroupita guianensis L. flower against generalist herbivore, Spodoptera litura Fab. and an earthworm, Eisenia foetida Savigny

    Science.gov (United States)

    Novel chemistries in botanical insecticides may provide alternatives to, or development of synthetic insecticides suitable for controlling the Lepidopteran pests, like Spodoptera litura (F.). Many botanical chemistries are biodegradable, and have lower mammalian toxicity. Eight natural chemical comp...

  19. Purification and identification of metabolites produced by Bacillus cereus and B. subtilis active against Meloidogyne exigua, and their in silico interaction with a putative phosphoribosyltransferase fromM. incognita

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    DENILSON F. OLIVEIRA

    2014-06-01

    Full Text Available To contribute to the development of products to controlMeloidogyne exigua, the bacteria Bacillus cereus and B. subtilis were cultivated in liquid medium to produce metabolites active against this plant-parasitic nematode. Fractionation of the crude dichloromethane extracts obtained from the cultures afforded uracil, 9H-purine and dihydrouracil. All compounds were active against M. exigua, the latter being the most efficient. This substance presented a LC50 of 204 µg/mL against the nematode, while a LC50 of 260 µg/mL was observed for the commercial nematicide carbofuran. A search for protein-ligand complexes in which the ligands were structurally similar to dihydrouracil resulted in the selection of phosphoribosyltransferases, the sequences of which were used in an in silico search in the genome of M. incognita for a similar sequence of amino acids. The resulting sequence was modelled and dihydrouracil and 9H-purine were inserted in the active site of this putative phosphoribosyltransferase resulting in protein-ligand complexes that underwent molecular dynamics simulations. Calculation of the binding free-energies of these complexes revealed that the dissociation constant of dihydrouracil and 9H-purine to this protein is around 8.3 x 10-7 and 1.6 x 10-6 M, respectively. Consequently, these substances and the putative phosphoribosyltransferase are promising for the development of new products to control M. exigua.

  20. Activity of chalcones derived from 2,4,5-trimethoxybenzaldehyde against Meloidogyne exigua and in silico interaction of one chalcone with a putative caffeic acid 3-O-methyltransferase from Meloidogyne incognita.

    Science.gov (United States)

    Nunes, Alexandro Silva; Campos, Vicente Paulo; Mascarello, Alessandra; Stumpf, Taisa Regina; Chiaradia-Delatorre, Louise Domenghini; Machado, Alan Rodrigues Teixeira; Santos Júnior, Helvécio Martins; Yunes, Rosendo Augusto; Nunes, Ricardo José; Oliveira, Denilson Ferreira

    2013-12-01

    Meloidogyne exigua is a parasitic nematode of plants that causes great losses to coffee farmers. In an effort to develop parasitic controls, 154 chalcones were synthesized and screened for activity against this nematode. The best results were obtained with (2E)-1-(4'-nitrophenyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (6) with a 50% lethal concentration (LC50) of 171 μg/ml against M. exigua second-stage juveniles, in comparison to the commercially-available nematicide carbofuran which had an LC50 of 260 μg/ml under the same conditions. When coffee plants were used, 6 reduced the nematode population to ~50% of that observed in control plants. To investigate the mechanism of action of 6, an in silico study was carried out, which indicated that 6 may act against M. exigua through inhibition of a putative caffeic acid 3-O-methyltransferase homodimer, the amino acid sequence of which was determined by examining the genome of Meloidogyne incognita.

  1. Molecular identification and characterization of the Orco orthologue of Spodoptera litura

    Institute of Scientific and Technical Information of China (English)

    Zhong-Nan Wu; Xi Chen; Yong-Jun Du; Jing-Jiang Zhou; Qi-Chuan ZhuGe

    2013-01-01

    A highly conserved and broadly expressed receptor protein Orco (olfactory coreceptor) is crucial for insect olfaction,and an orthologue of Orco has been identified in several insect species.Here we report the identification and characterization of Orco from Spodoptera litura.The protein displays high primary amino acid sequence conservation with other previously identified Orco orthologues.Bioinformatic analysis revealed that it has common features with other members of the Orco subfamily:seven-transmembrane domains with intracellular N-terminus and extracellular C-terminus.The transcript was detected in abundance in the chemosensory organs of the antennae of both male and female adults by real-time polymerase chain reaction analysis,and was localized at the bases of all categories of olfactory sensilla through in situ hybridization.

  2. Apoptosis of Spodoptera litura larval hemocytes induced by heavy metal zinc

    Institute of Scientific and Technical Information of China (English)

    XIA Qiang; SUN Hongxia; HU Xinjun; SHU Yinghua; GU Dexiang; ZHANG Guren

    2005-01-01

    By adding different amount of zinc into the artificial medium of the insect larvae, the zinc-induced apoptosis of the larvae haemocytes of the herbivorous insect Spodoptera litura Fabricius was investigated with flow cytometer. The results showed that the increase of zinc dose in the artificial feed led to the accumulations of zinc in the larval hemolymph and fat body, and more zinc was accumulated in fat body than in hemolymph. The apoptosis of hemocytes was significantly induced at high zinc concentration (1000 mg·kg-1) in the insect diet, and the apoptosis rate was 63.63%, which was remarkably higher than that at control and lower concentrations (50-500 mg·kg-1). This suggests that the high dose of zinc in the artificial diet of S. Litura larvae could induce the apoptosis of the larval hemocytes of S. Litura.

  3. Repellent and insecticidal activities of Melia azedarach L. against cotton leafworm, Spodoptera littoralis (Boisd.).

    Science.gov (United States)

    Farag, Mohamed; Ahmed, Mohamed H M; Yousef, Heba; Abdel-Rahman, Adel A H

    2011-01-01

    A crude acetone extract and oil of ripe fruits from Melia azedarach L. were evaluated against the 2nd and 4th instar larvae of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae). Both oil and extract exhibited highly significant growth inhibition at all concentrations tested, while the oil of M. azedarach recorded higher insecticidal activity against both instars than the crude extract. GC-MS analysis of the oil revealed the presence of linoleic acid methyl ester, oleic acid methyl ester, and free oleic acid as the main components in addition to hexadecanol, palmitic acid, methyl esters of stearic acid and myristic acid. Fatty acids and their esters were not only the main constituents of essential oil from the ripe fruits of M. azedarach, but also mainly responsible for the insecticidal and growth inhibition activity against S. littoralis.

  4. Host plants of leaf worm, Spodoptera litura (Fabricius (Lepidoptera: noctuidae in Pakistan

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    Munir Ahmad

    2013-04-01

    Full Text Available Spodoptera litura is a notorious leaf feeding insect pest of more than one hundred plants around the Asia-Pacific region. Host plant survey for two years from three different locations in cotton belt revealed 27 plant species as host plants of S. litura belonging to 25 genera of 14 families including cultivated crops, vegetables, weeds, fruits and ornamental plants. Major host plants on which it thrived for maximum period were Gossypium hirsutum L., Ricinus communis L., Brassica oleracea var. botrytis L., Colocasia esculenta L., Trianthema portulacastrum L. and Sesbania sesban L.. Eggs were also collected from tree plants but larvae did not complete their development. Reliance of S. litura on major plant species of cultivated crops necessitates their regular monitoring especially during March to April for their population abundance and early warning for their management on commercial crops like cotton.

  5. The complete mitochondrial genome of the common cutworm, Spodoptera litura (Lepidoptera: Noctuidade).

    Science.gov (United States)

    Liu, Qiu-Ning; Zhu, Bao-Jian; Dai, Li-Shang; Wang, Lei; Qian, Cen; Wei, Guo-Qing; Liu, Chao-Liang

    2016-01-01

    The complete mitochondrial genome (mitogenome) of Spodoptera litura (Lepidoptera: Noctuidae) was determined to be 15,374 bp (GenBank accession No. KF543065), including 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes and an A + T-rich region. It has the typical gene organization and order of mitogenomes from lepidopteran insects. The AT skew of this mitogenome was slightly positive and the nucleotide composition was also biased toward A + T nucleotides (81.03%). All PCGs were initiated by ATN codons, except for cytochrome c oxidase subunit 1 (cox1) gene which was initiated by CGA. Four of the 13 PCGs harbor the incomplete termination codon by T. All the tRNA genes displayed a typical clover-leaf structure of mitochondrial tRNA, with the exception of trnS1 (AGN). The A + T-rich region of the mitogenome was 326 bp in length.

  6. Quantitative proteomics of Spodoptera frugiperda cells during growth and baculovirus infection.

    Science.gov (United States)

    Carinhas, Nuno; Robitaille, Aaron Mark; Moes, Suzette; Carrondo, Manuel José Teixeira; Jenoe, Paul; Oliveira, Rui; Alves, Paula Marques

    2011-01-01

    Baculovirus infection of Spodoptera frugiperda cells is a system of choice to produce a range of recombinant proteins, vaccines and, potentially, gene therapy vectors. While baculovirus genomes are well characterized, the genome of S. frugiperda is not sequenced and the virus-host molecular interplay is sparsely known. Herein, we describe the application of stable isotope labeling by amino acids in cell culture (SILAC) to obtain the first comparative proteome quantitation of S. frugiperda cells during growth and early baculovirus infection. The proteome coverage was maximized by compiling a search database with protein annotations from insect species. Of interest were differentially proteins related to energy metabolism, endoplasmic reticulum and oxidative stress, yet not investigated in the scope of baculovirus infection. Further, the reduced expression of key viral-encoded proteins early in the infection cycle is suggested to be related with decreased viral replication at high cell density culture. These findings have implications for virological research and improvement of baculovirus-based bioprocesses.

  7. Vip3Aa induces apoptosis in cultured Spodoptera frugiperda (Sf9) cells.

    Science.gov (United States)

    Jiang, Kun; Mei, Si-Qi; Wang, Ting-Ting; Pan, Jin-Hua; Chen, Yue-Hua; Cai, Jun

    2016-09-15

    The vegetative insecticidal proteins (Vip) secreted by many Bacillus thuringiensis strains during their vegetative growth stage are regarded as second generation insecticidal proteins, as they share no sequence or structural homology with known crystal insecticidal proteins (Cry) and have a broad insecticidal spectrum. Compared with insecticidal crystal proteins (ICPs), the insecticidal mechanisms of Vips have been little studied. Here we investigated the mechanism responsible for Vip3Aa toxicity in cultured insect cells. Using, flow cytometry analyzes, TUNEL staining and DNA fragmentation assays, we show that Vip3Aa can induce apoptosis in Spodoptera frugiperda (Sf9) cells and cause cells to arrest at the G2/M phase. We also show that Vip3Aa can disrupt mitochondrial membrane potential (ΔΨm), leading to the activation of Sf-caspase-1, suggesting that a mitochondrial mediated and caspase dependent pathway may be involved in Vip3Aa-induced apoptosis in Sf9 cells.

  8. Biotic potential and reproductive parameters of Spodoptera eridania (Stoll (Lepidoptera, Noctuidae in the laboratory

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    Débora Goulart Montezano

    2013-09-01

    Full Text Available Biotic potential and reprodutcive parameters of Spodoptera eridania (Stoll (Lepidoptera, Noctuidae in the laboratory: This study aimed to evaluate the biotic potential and reproductive parameters of Spodoptera eridania (Stoll, 1782 under controlled conditions (25 ± 1ºC, 70 ± 10% RH and 14 hour photophase. The longevity, pre-, post- and oviposition periods, fecundity and fertility of 15 couples was evaluated. The longevity of females (10.80 days was not significantly higher than those of males (9.27 days. The mean durations of the pre, post and oviposition periods were 2.067, 0.600 and 8.133 days, respectively. The mean fecundity per female was 1,398 eggs and the mean fertility was 1,367.50 larvae. On average, females copulated 1.133 times. A strong positive correlation was observed between the number of mating and fecundity (r = 0.881, P <0.001. However a strong negative correlation was observed between the number of copulations and the duration of the pre-oviposition period (r = -0.826, P = 0.002 and longevity (r = -0.823, P = 0.001. The biotic potential of S. eridania was estimated at 1.894 x 10(25 individuals/female/year. The net reproductive rate (Ro was 560.531 times per generation and the mean generation time (T was 35.807 days. The intrinsic rate of increase (rm was 0.177, with a finite rate of increase (l of 1.193, per week

  9. Identification and functional characterization of sex pheromone receptors in the common cutworm (Spodoptera litura).

    Science.gov (United States)

    Zhang, Jin; Yan, Shuwei; Liu, Yang; Jacquin-Joly, Emmanuelle; Dong, Shuanglin; Wang, Guirong

    2015-01-01

    Male moths can finely discriminate the sex pheromone emitted by conspecific females from similar compounds. Pheromone receptors, expressed on the dendritic membrane of sensory neurons housed in the long trichoid sensilla of antennae, are thought to be associated with the pheromone reception. In this study, we identified and functionally characterized 4 pheromone receptors from the antennae of Spodoptera litura (Lepidoptera: Noctuidae). A tissue distribution analysis showed that the expression of the 4 SlituPRs was restricted to antennae. In addition, SlituOR6 and SlituOR13 were specifically expressed in male antennae whereas SlituOR11 and SlituOR16 were male-biased. Functional investigation by heterologous expression in Xenopus oocytes revealed that SlituOR6 was specifically tuned to the second major pheromone component, Z9,E12-14:OAc, SlituOR13 was equally tuned to Z9,E12-14:OAc and Z9-14:OAc, with a small response to the major pheromone component Z9,E11-14:OAc, SlituOR16 significantly responded to the behavioral antagonist Z9-14:OH, whereas SlituOR11 did not show response to any of the pheromone compounds tested in this study. Our results provide molecular data to better understand the mechanisms of sex pheromone detection in the moth S. litura and bring clues to investigate the evolution of the sexual communication channel in closely related species through comparison with previously reported pheromone receptors in other Spodoptera species.

  10. Status of resistance to Bt maize in Spodoptera frugiperda: lessons from Puerto Rico.

    Science.gov (United States)

    Storer, Nicholas P; Kubiszak, Mary E; Ed King, J; Thompson, Gary D; Santos, Antonio Cesar

    2012-07-01

    In 2006, reports of potential Spodoptera frugiperda resistance to TC1507 maize in Puerto Rico were received. Subsequent investigation confirmed that pest populations collected from several sites in Puerto Rico were largely unaffected by the Cry1F protein in bioassays, with resistance ratios likely in excess of 1000. Since then, we have continued monitoring populations in Puerto Rico and in southern areas of the mainland US. The majority of the collections from Puerto Rico continue to show high levels of Cry1F resistance whereas populations collected from the southern US mainland continue to show full susceptibility to Cry1F and TC1507 maize. It does not appear that resistant populations have spread to any measurable extent from Puerto Rico to mainland US, nor that local selection pressure from Cry1F-expressing maize or cotton production in the southern US has caused a measurable change in population susceptibility. Lessons learned from Puerto Rico are being applied in other parts of the Americas where TC1507 maize is grown and additional steps being taken to protect the long-term durability of Cry1F in maize in areas where similar selection pressure may be expected. Tactics include using locally-adapted germplasm that contain native Spodoptera resistance, a robust education program to teach end-users about the potential for resistance to develop appropriate crop stewardship, resistance monitoring, and the use of insecticides under high S. frugiperda pressure. Perhaps most importantly, pyramided trait products that produce two or more different Bt proteins are being introduced to further delay resistance development to Cry1F.

  11. BIOLOGICAL CONTROL OF SPODOPTERA FRUGIPERDA EGGS USING TELENOMUS REMUS NIXON IN MAIZE-BEAN-SQUASH POLYCULTURE

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    Antonio GutiA©rrez-MartAnez

    2012-01-01

    Full Text Available The maize earworm, Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae, is an important pest in maize. Telenomus remus Nixon (Hymenoptera: Scelionidae is an important control agent of this pest due to its capacity to invade the whole egg mass. The percentage of parasitism by Telenomus remus Nixon (Hymenoptera: Scelionidae on Spodoptera frugiperda (J.E. Smith (Lepidoptera: Noctuidae eggs was evaluated in maize-bean, maize-squash and maize-bean-squash polyculture and maize monoculture systems. Data were analyzed statistically by using a Poisson regression (log-linear model. The analysis showed highly significant differences in the percentage of parasitism of S. frugiperda eggs by T. remus in plots with jarocho crema maize in polyculture systems (91.00±1.42% compared to the yellow maize genotype (68.90±3.10%. Parasitism percentages increased in the jarocho crema maize genotype in maize-bean, maize-squash, maize-bean-squash polycultures and maize monoculture by 87.88±3.27%, 89.75±1.99, 99.50±0.19 and 86.88±2.66%, respectively and in the yellow maize genotype they dropped by 70.00±7.05, 64.50±5.63, 77.88±6.51 and 63.25±5.20%, respectively. The percentage of T. remus parasitism on S. frugiperda eggs was found to be affected by the genotype of maize, bean and squash, polyculture system, weeds, densities of the host eggs and numbers and quality of egg masses.

  12. Kinetic analysis of in vitro production of wild-type Spodoptera frugiperda nucleopolyhedrovirus

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    Andréa Farias de Almeida

    2010-04-01

    Full Text Available In this study, the kinetic behavior of Sf9 and Sf21 cells used in the production of a baculovirus biopesticide to control the pest of corn Spodoptera frugiperda was analyzed. Kinetic variables such as maximum specific growth rate, cell productivity, mean rate of infection, as well as the mean rate of occlusion body production were determined during the infection of these cell-lines with the extracellular virus of the S. frugiperda nucleopolyhedrovirus (SfMNPV. The Sf9 cell-line resulted in better viral production results (5.0 x 10(8 OB/mL than the Sf21 cell-line (2.5 x 10(8 OB/mL.Neste trabalho, analisou-se o comportamento cinético das células Sf9 e Sf21 utilizadas na produção de biopesticida para o controle de Spodoptera frugiperda. Variáveis cinéticas, como velocidade específica máxima de crescimento, produtividade em células, velocidade média de infecção e a velocidade média de produção de OB foram determinadas durante a infecção destas linhagens com o vírus extracelular do nucleopoliedrovirus de S. frugiperda. A linhagem Sf9 resultou em melhores resultados de produção do baculovírus (5 x 10(8 OB/mL, quando comparada à linhagem Sf21 (2,5 x 10(8 OB/mL e outras linhagens da literatura.

  13. Development of insect-resistant transgenic cotton with chimeric TVip3A* accumulating in chloroplasts.

    Science.gov (United States)

    Wu, Jiahe; Luo, Xiaoli; Zhang, Xiangrong; Shi, Yuejing; Tian, Yingchuan

    2011-10-01

    An optimized vip3A gene, designated as vip3A* was chemically synthesized and a thi1 gene chloroplast transit peptide coding sequence was attached to its 5' end to produce the tvip3A*. vip3A* and tvip3A* genes were transformed into Gossypium hirsutum cv. Zhongmiansuo35. Of 42 independent transformants, 36 were positive for the vip3A* or tvip3A* gene. Four independent transgenic T1 lines with single-copy insertions and unchanged phenotypes (CTV1 and CTV2 for tvip3A*, and CV1 and CV2 for vip3A*) were selected by Southern blotting, and subjected to an insect bioassay and field assessment. Four homozygous T2 transgenic lines were then selected and the amount of expressed Vip3A* protein was determined by western blotting and ELISA. The protein concentrations of CTV1 and CTV2 were about three-fold higher than those of CV1 and CV2. As expected, the Vip3A* protein of CTV1 and CTV2 were transported to the chloroplasts, where they accumulated. The Vip3A* protein concentration in the chloroplasts of CTV1 and CTV2 was about 15-fold of that of CV1 and CV2. All four transgenic lines showed 100% mortality against fall armyworm (Spodoptera frugiperda) and beet armyworm (Spodoptera exigua) by insect bioassay. Moreover, CTV1 and CTV2 exhibited 100% mortality against cotton bollworm (CBW, Helicoverpa zea), whereas CV1 and CV2 showed 75.0% and 72.5% mortality against CBW, respectively. The field bioassay indicated that CTV1 and CTV2 were more resistant to CBW than CV1 and CV2. Our results suggest that the two tvip3A* transgenic lines (CTV1 and CTV2) can be used to develop insect-resistant cultivars and could be used as a resource for raising multi-toxins-expressing transgenic cotton.

  14. Suscetibilidade de Spodoptera Frugiperda a isolados geográficos de um vírus de poliedrose nuclear Spodoptera Frugiperda susceptibility to nuclear polyhedrosis virus geographical isolates

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    Sérgio Arce Gomez

    1999-09-01

    Full Text Available O presente trabalho objetivou verificar a suscetibilidade de larvas de segundo ínstar de Spodoptera frugiperda (Smith, 1797 a sete isolados geográficos de um vírus de poliedrose nuclear (VPN, conduzindo-se sete bioensaios no Laboratório de Patologia de Insetos da Embrapa-Centro Nacional de Pesquisa de Soja, Londrina. Para cada isolado preparou-se dieta artificial contendo 0, 2x10³, 4x10³, 8x10³, 16x10³, 32x10³ e 64x10³ corpos poliédricos de inclusão (CPI/mL. Cada dose foi oferecida às larvas em copos de plástico de 50 mL, sob condições controladas (temperatura: 26±2ºC; umidade relativa: 60±10%; fotófase:14 horas. A análise (Probits realizada sobre o somatório de larvas mortas (contadas, diariamente, do quinto ao décimo quarto dia após a inoculação mostrou, com base na ausência de sobreposição das amplitudes dos intervalos de confiança das concentrações letais médias (CL50, que: o isolado de Sertaneja, PR (5.631 CPI/mL, foi o mais virulento; o da Guatemala (11.520 CPI/mL equivaleu aos de Ponta Grossa, PR (14.184 CPI/mL, Argentina (15.891 CPI/mL e Alabama, EUA (17.558 CPI/mL, mas foi superior aos isolados de Louisiana, EUA (19.325 CPI/mL e Sete Lagoas, MG (25.310 CPI/mL. A variação do tempo letal médio, de 8,3 a 10 dias, não foi significativa em relação aos isolados.In order to verify the Spodoptera frugiperda (Smith,1797 second instar larvae susceptibility to seven nuclear polyhedrosis virus (NPV geographical isolates, seven bioassays were carried out at Embrapa-Centro Nacional de Pesquisa de Soja, Insect Pathology Laboratory, Londrina, Paraná State, Brazil. Artificial diet containing 0 (control, 2x10³, 4x10³, 8x10³, 16x10³, 32x10³, and 64x10³ polyhedral inclusion bodies (PIB/mL was prepared for each virus isolate; each dose was offered, in 50 mL plastic cups to the larvae under controlled conditions (temperature 26±2ºC; relative humidity: 60±10% and photophase: 14 hours. The statistical analysis

  15. Differential protection of Cry1Fa toxin against Spodoptera frugiperda larval gut proteases by cadherin orthologs correlates with increased synergism.

    Science.gov (United States)

    Rahman, Khalidur; Abdullah, Mohd Amir F; Ambati, Suresh; Taylor, Milton D; Adang, Michael J

    2012-01-01

    The Cry proteins produced by Bacillus thuringiensis (Bt) are the most widely used biopesticides effective against a range of crop pests and disease vectors. Like chemical pesticides, development of resistance is the primary threat to the long-term efficacy of Bt toxins. Recently discovered cadherin-based Bt Cry synergists showed the potential to augment resistance management by improving efficacy of Cry toxins. However, the mode of action of Bt Cry synergists is thus far unclear. Here we elucidate the mechanism of cadherin-based Cry toxin synergism utilizing two cadherin peptides, Spodoptera frugiperda Cad (SfCad) and Manduca sexta Cad (MsCad), which differentially enhance Cry1Fa toxicity to Spodoptera frugiperda neonates. We show that differential SfCad- and MsCad-mediated protection of Cry1Fa toxin in the Spodoptera frugiperda midgut correlates with differential Cry1Fa toxicity enhancement. Both peptides exhibited high affinity for Cry1Fa toxin and an increased rate of Cry1Fa-induced pore formation in S. frugiperda. However, only SfCad bound the S. frugiperda brush border membrane vesicle and more effectively prolonged the stability of Cry1Fa toxin in the gut, explaining higher Cry1Fa enhancement by this peptide. This study shows that cadherin fragments may enhance B. thuringiensis toxicity by at least two different mechanisms or a combination thereof: (i) protection of Cry toxin from protease degradation in the insect midgut and (ii) enhancement of pore-forming ability of Cry toxin.

  16. RNA interference reveals allatotropin functioning in larvae and adults of Spodoptera frugiperda (Lepidoptera, Noctuidae

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    I.T.E. Hassanien

    2014-05-01

    Full Text Available The allatotropin of S. frugiperda (Spofr-AT and its cDNA sequence were characterized 10 years ago, but no functional analyses of the peptide are available. Here we used the RNA interference technique to study the effects of Spofr-AT gene suppression on juvenile hormone (JH and ecdysteroid titers in the hemolymph of larvae, virgin and mated females, and of males. Spofr-AT gene silencing in last instar larvae resulted in an increase in the amount of JH III and 20-hydroxyecdysone in the hemolymph of the animals, corresponding to an acceleration of the prepupal commitment and transformation to the pupa. Mated females showed much higher JH titers in their hemolymph than virgins and laid almost twice the number of eggs. Spofr-AT gene silencing in freshly ecdysed females led to a further increase in egg production and oviposition, but had only a minor effect on the hemoylmph JH titer. Mated females contain considerable amounts of JH I and JH II in their hemoylmph, which are thought to be received from males during copulation. To confirm this hypothesis, we measured the amount of JH homologs in the male accessory reproductive glands (MARG before mating and in the bursa copulatrix (BC of the female after mating. MARG contained high amounts of JH I and JH II, which are transferred to the BC during copulation. One day after mating, JH disappeared from the BC and was then found in the hemolymph of the females. In conclusion, Spofr-AT acts as a true allatotropin in larvae and adults of both sexes of the armyworm.

  17. Differential activity of multiple saponins against omnivorous insects with varying feeding preferences

    Science.gov (United States)

    A variety of saponin glycosides and aglycones from seven different plant families (Aquifoliaceae, Asparagaceae, Caryophyllaceae, Dioscoreaceae, Leguminosae, Rosaceae, Sapindaceae) were tested against the corn earworm, Helicoverpa zea, and the fall armyworm, Spodoptera frugiperda. The corn earworm fe...

  18. The Green Gut: Chlorophyll Degradation in the Gut of Spodoptera littoralis.

    Science.gov (United States)

    Badgaa, Amarsanaa; Büchler, Rita; Wielsch, Natalie; Walde, Marie; Heintzmann, Rainer; Pauchet, Yannik; Svatos, Ales; Ploss, Kerstin; Boland, Wilhelm

    2015-11-01

    Chlorophylls, the most prominent natural pigments, are part of the daily diet of herbivorous insects. The spectrum of ingested and digested chlorophyll metabolites compares well to the pattern of early chlorophyll-degradation products in senescent plants. Intact chlorophyll is rapidly degraded by proteins in the front- and midgut. Unlike plants, insects convert both chlorophyll a and b into the corresponding catabolites. MALDI-TOF/MS imaging allowed monitoring the distribution of the chlorophyll catabolites along the gut of Spodoptera littoralis larvae. The chlorophyll degradation in the fore- and mid-gut is strongly pH dependent, and requires alkaline conditions. Using LC-MS/MS analysis we identified a lipocalin-type protein in the intestinal fluid of S. littoralis homolog to the chlorophyllide a binding protein from Bombyx mori. Widefield and high-resolution autofluorescence microscopy revealed that the brush border membranes are covered with the chlorophyllide binding protein tightly bound via its GPI-anchor to the gut membrane. A function in defense against gut microbes is discussed.

  19. Differential contribution of transcription factors to Arabidopsis thaliana defence against Spodoptera littoralis.

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    Fabian eSchweizer

    2013-02-01

    Full Text Available In response to insect herbivory, Arabidopsis plants activate the synthesis of the phytohormone jasmonate-isoleucine (JA-Ile, which binds to a complex consisting of the receptor COI1 and JAZ repressors. Upon proteasome-mediated JAZ degradation, basic helix-loop-helix transcription factors (TFs MYC2, MYC3, and MYC4 become activated and this results in the expression of defence genes. Although the jasmonate (JA pathway is known to be essential for the massive transcriptional reprogramming that follows herbivory, there is however little information on other TFs that are required for defence against herbivores and whether they contribute significantly to JA-dependent defence gene expression. By transcriptome profiling, we identified 41 TFs that were induced in response to herbivory by the generalist Spodoptera littoralis. Among them, nine genes, including WRKY18, WRKY40, ANAC019, ANAC055, ZAT10, ZAT12, AZF2, ERF13, and RRTF1, were found to play a significant role in resistance to S. littoralis herbivory. However, compared to the triple mutant myc234 that is as sensitive as coi1-1 to herbivory, knockout lines of these nine TFs were only partially more sensitive to S. littoralis and showed only minor gene expression changes at the whole genome level. Data thus reveal that MYC2, MYC3, and MYC4 are master regulators of Arabidopsis resistance to a generalist herbivore and identify new genes involved in insect defence.

  20. Toxic effects of Citrus aurantium and C. limon essential oils on Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Villafañe, Emilio; Tolosa, Diego; Bardón, Alicia; Neske, Adriana

    2011-09-01

    Citrus aurantium and C. limon were selected in the search for natural plant insecticides. The essential oils of C. aurantium and C. limon and ethanol extracts of the seeds, pulp, albedo, and peel of C. aurantium were incorporated into the larval diet of the lepidopteran pest Spodoptera frugiperda. Larval and pupal mortality were quantified and adult malformation was observed. C aurantium essential oil had antifeedant action and the mixture of albedo ethanol extract and C aurantium essential oil had toxic effects on S. frugiperda larvae at early stages, when they had not yet produced major damage to the crop. Our results indicated that a mixture of ethanol extract of albedo and C. aurantium essential oil (250 microg of extract mix per g of diet) deterred feeding by 46% and had the highest larval mortality (100%) of the materials tested. The peel extract (250 microg per g of diet) produced an increment in growth rate and diet consumption. However, 40% of the larval and 45% of the pupal populations died after 96 h of treatment. The blend of essential oil and C. aurantium albedo ethanol extract showed the lowest consumption and a poor nutrient conversion into biomass. Finally, the presence of D-limonene and nootkatone in the peel ethanol extract, and C. limon and C. aurantium essential oils, may be the cause of the response in the feeding behavior and toxic effects found on S. frugiperda.

  1. Mitochondria are involved in apoptosis induced by ultraviolet radiation in lepidopteran Spodoptera litura cell line

    Institute of Scientific and Technical Information of China (English)

    Shigang Shan; Kaiyu Liu; Jianxin Peng; Hanchao Yao; Yi Li; Huazhu Hong

    2009-01-01

    Mitochondria are involved in apoptosis of mammalian cells and even single-cell organisms, but mitochondria are not required in apoptosis in cultured Drosophila cells such as S2 and BG2 cell lines. It is not very clear whether mitochondria are involved in apoptosis in other insect cells such as lepidopteran cell lines. Thus, we determined to elucidate the role of mitochondria in apoptosis induced by ultraviolet radiation in Spodoptera litura (Lepidoptera: Noctuidae) cell line (SL-ZSU-1). The Western blot results suggested that cytochrome c in the ultraviolet-treated SL-1 cells was released from the mitochondria to cytosol as early as 4 h after the induction of ultraviolet radiation and increased in the cytosolic fractions in a time-dependent manner. Flow cytometric analysis of mitochondrial membrane potential (△Ψm) of SL-ZSU-1 cell treated with ultraviolet-C (UV-C) light indicated the decrease in mitochondrial membrane potential was dependent on the times of ultraviolet treatment. Both of them are different from apoptosis in cultured Drosophila melanogaster cell lines (S2 and BG2) and it appears evident mitochondria are involved in apoptosis of the studied lepidopteran cells.

  2. Ovicidal activity of Atalantia monophylla (L) Correa against Spodoptera litura Fab. (Lepidoptera:Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    Kathirvelu Baskar; Chellaiah Muthu; Gnanaprakasam Antony Raj; Selvadurai Kingsley; Savarimuthu Ignacimuthu

    2012-01-01

    Objective: To evaluate the efficacy of Atalantia monophylla (A. monophylla) leaf in different solvent crude extracts and fractions against eggs of Spodoptera litura (S. litura). Methods:Hexane, ethyl acetate and chloroform solvent extracts of A. monophylla leaf and 12 fractions from hexane extract were screened at 5.0%, 2.5%, 1.0%and 0.5%for crude extracts and 1 000, 500, 250 and 125 mg/kg for fractions against the eggs of S. litura for the ovicidal activity. LC50 and LC90 were calculated using probit analysis. Results:Hexane crude extract showed maximum ovicidal activity of 61.94%at 5.0%concentration with a correlation value of r2=0.81, and least LC50 value of 3.06%. Hexane extract was fractionated using silica gel column chromatography and 12 fractions were obtained. Fraction 9 was active which showed maximum ovicidal activity of 75.61%at 1 000 mg/kg with the LC50 value of 318.65 mg/kg and LC90 value of 1 473.31 mg/kg. In linear regression analysis, significant and high correlation (r2=0.81%) was seen between concentration and ovicidal activity of hexane crude extracts and its active fraction. Conclusions:As per our knowledge, this is the first report for ovicidal activity of A. monophylla against S. litura, A. monophylla could be used for the management of S. litura and other insect pests.

  3. General up regulation of Spodoptera frugiperda trypsins and chymotrypsins allows its adaptation to soybean proteinase inhibitor.

    Science.gov (United States)

    Brioschi, Daniela; Nadalini, Larissa D; Bengtson, Mario H; Sogayar, Mari Cleide; Moura, Daniel S; Silva-Filho, Marcio C

    2007-12-01

    The existence of a diverse serine proteinase gene family in lepidopteran insects suggests they play a significant role in the insect adaptation to plant proteinase inhibitors. These proteinases have been shown to be involved in the process of proteolytic digestion in insect larvae. We carried out a selective transcriptome study of midguts from Spodoptera frugiperda larvae fed on a diet supplemented with soybean proteinase inhibitor (SPI). Using subtracted cDNA libraries made of gut-expressed transcripts, a total of 2100 partial sequences were obtained, of those 38% were related to digestive process. Two large and diverse groups of chymotrypsins and trypsins were obtained, and some of these proteinase-encoding genes were further characterized by quantitative RT-PCR. The transcription analyses revealed two groups: one group of genes constitutively expressed in the control larvae that is up regulated by introducing SPI to the diet, and a second group that is absent in the control but is induced by the SPI-rich diet. This observation suggests that adaptation of S. frugiperda to SPI involves de novo synthesis and also up regulation of existing enzymes. Proteases from intestines of larvae reared on a diet with SPI showed insensitivity to the inhibitor. The proteases were also insensitive to a broad-spectrum potato proteinase inhibitor preparation. We propose that adaptation of S. frugiperda to SPI follows a "shotgun" approach, based on a general up regulation of a large set of endoproteinases.

  4. Insecticidal activity of two proteases against Spodoptera frugiperda larvae infected with recombinant baculoviruses

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    Nagata Tatsuya

    2010-06-01

    Full Text Available Abstract Background Baculovirus comprise the largest group of insect viruses most studied worldwide, mainly because they efficiently kill agricutural insect pests. In this study, two recombinant baculoviruses containing the ScathL gene from Sarcophaga peregrina (vSynScathL, and the Keratinase gene from the fungus Aspergillus fumigatus (vSynKerat, were constructed. and their insecticidal properties analysed against Spodoptera frugiperda larvae. Results Bioassays of third-instar and neonate S. frugiperda larvae with vSynScathL and vSynKerat showed a decrease in the time needed to kill the infected insects when compared to the wild type virus. We have also shown that both recombinants were able to increase phenoloxidase activity in the hemolymph of S. frugiperda larvae. The expression of proteases in infected larvae resulted in destruction of internal tissues late in infection, which could be the reason for the increased viral speed of kill. Conclusions Baculoviruses and their recombinant forms constitute viable alternatives to chemical insecticides. Recombinant baculoviruses containing protease genes can be added to the list of engineered baculoviruses with great potential to be used in integrated pest management programs.

  5. Stability of a Spodoptera frugiperda Nucleopolyhedrovirus Deletion Recombinant during Serial Passage in Insects▿ †

    Science.gov (United States)

    Simón, Oihane; Williams, Trevor; Possee, Robert D.; López-Ferber, Miguel; Caballero, Primitivo

    2010-01-01

    The stabilities of the Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) complete genome bacmid (Sfbac) and a deletion recombinant (Sf29null) in which the Sf29 gene was replaced by a kanamycin resistance cassette were determined during sequential rounds of per os infection in insect larvae. The Sf29 gene is a viral factor that determines the number of virions in occlusion bodies (OBs). The Sf29null bacmid virus was able to recover the Sf29 gene during passage. After the third passage (P3) of Sf29null bacmid OBs, the population was observed to reach an equilibrium involving a mixture of those with a kanamycin resistance cassette and those with the Sf29 gene. The biological activity of Sf29null bacmid OBs at P3 was similar to that of Sfbac OBs. The recovered gene in the Sf29null virus was 98 to 100% homologous to the Sf29 genes of different SfMNPV genotypes. Reverse transcription-PCR analysis of uninoculated S. frugiperda larvae confirmed the expression of the SfMNPV ie-0 and Sf29 genes, indicating that the insect colony harbors a covert SfMNPV infection. Additionally, the nonessential bacterial artificial chromosome vector was spontaneously deleted from both viral genomes upon passage in insects. PMID:20008167

  6. Targeting the Diuretic Hormone Receptor to Control the Cotton Leafworm, Spodoptera littoralis

    Science.gov (United States)

    Apone, Fabio; Ruggiero, Alessandra; Tortora, Assunta; Tito, Annalisa; Grimaldi, Maria Rosaria; Arciello, Stefania; Andrenacci, Davide; Lelio, Ilaria Di; Colucci, Gabriella

    2014-01-01

    The cotton leafworm, Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae), is one of the most devastating pests of crops worldwide. Several types of treatments have been used against this pest, but many of them failed because of the rapid development of genetic resistance in the different insect populations. G protein coupled receptors have vital functions in most organisms, including insects; thus, they are appealing targets for species-specific pest control strategies. Among the insect G protein coupled receptors, the diuretic hormone receptors have several key roles in development and metabolism, but their importance in vivo and their potential role as targets of novel pest control strategies are largely unexplored. With the goal of using DHR genes as targets to control S. littoralis, we cloned a corticotropin-releasing factor-like binding receptor in this species and expressed the corresponding dsRNA in tobacco plants to knock down the receptor activity in vivo through RNA interference. We also expressed the receptor in mammalian cells to study its signaling pathways. The results indicate that this diuretic hormone receptor gene has vital roles in S. littoralis and represents an excellent molecular target to protect agriculturallyimportant plants from this pest. PMID:25368043

  7. The Spodoptera frugiperda effector caspase Sf-caspase-1 becomes unstable following its activation.

    Science.gov (United States)

    Ying, Zhongfu; Li, Ao; Lu, Zhaodan; Wu, Chunfeng; Yin, Hanqi; Yuan, Meijin; Pang, Yi

    2013-08-01

    Sf-caspase-1 is the principal effector caspase in Spodoptera frugiperda cells. Like the caspases in other organisms, Sf-caspase-1 is processed by upstream caspases to form an active heterotetramer composed of the p19 and p12 subunits. The regulation of active caspases is crucial for cellular viability. In mammal cells, the subunits and the active form of caspase-3 were rapidly degraded relative to its proenzyme form. In the present study, the S. frugiperda Sf9 cells were transiently transfected with plasmids encoding different fragments of Sf-caspase-1: the pro-Sf-caspase-1 (p37), a prodomain deleted fragment (p31), a fragment containing the large subunit and the prodomain (p25), the large subunit (p19), and the small subunit (p12). Flow cytometry and Western blot analysis revealed that p12, p19, and p25 were unstable in the transfected cells, in contrast to p37 and p31. Lactacystin, a proteasome inhibitor, increased the accumulation of the p19 and p12 subunits, suggesting that the degradation is performed by the ubiquitin-proteasome system. During the activation, the Sf-caspase-1 produces an intermediate form and then undergoes proteolytic processing to form active Sf-caspase-1. We found that both the active and the intermediate form were unstable, indicating that once activated or during its activation, the Sf-caspase-1 was unstable.

  8. Transfection of Spodoptera frugiperda Insect Cell and Production of Recombinant Protein

    Directory of Open Access Journals (Sweden)

    Özlem Üstün Aytekin

    2015-12-01

    Full Text Available Rekombinant protein üretimi son yıllarda sıklıkla çalışılan bir konudur. Rekombinant protein üretimi için çalışılan konakçılar arasında kısa ikilenme süresi, protein katlanmasındaki avantajları, süspanse kültürde çalışılabilmesi nedeni ile Spodoptera frugiperda böcek hücre hatları; yüksek verimliliği, büyük gen bölgelerini eksprese etme kapasitesi ve hızlı cevap vermesi nedeni ile de transfeksiyon vektörü olarak baculovirus (BV tercih edilmektedir. Bu derlemede rekombinant protein üretimini etkileyen bu hücre hatları, üretim ortamları, uygun üretim koşulları, baculovirusler, transfeksiyon metotları, rekombinant protein üretiminde kullanılan biyoreaktör sistemleri, çalışma modları ve biyoreaktör ekipmanları açıklanmaktadır.

  9. The complete sequence of the first Spodoptera frugiperda Betabaculovirus genome: a natural multiple recombinant virus.

    Science.gov (United States)

    Cuartas, Paola E; Barrera, Gloria P; Belaich, Mariano N; Barreto, Emiliano; Ghiringhelli, Pablo D; Villamizar, Laura F

    2015-01-20

    Spodoptera frugiperda (Lepidoptera: Noctuidae) is a major pest in maize crops in Colombia, and affects several regions in America. A granulovirus isolated from S. frugiperda (SfGV VG008) has potential as an enhancer of insecticidal activity of previously described nucleopolyhedrovirus from the same insect species (SfMNPV). The SfGV VG008 genome was sequenced and analyzed showing circular double stranded DNA of 140,913 bp encoding 146 putative ORFs that include 37 Baculoviridae core genes, 88 shared with betabaculoviruses, two shared only with betabaculoviruses from Noctuide insects, two shared with alphabaculoviruses, three copies of own genes (paralogs) and the other 14 corresponding to unique genes without representation in the other baculovirus species. Particularly, the genome encodes for important virulence factors such as 4 chitinases and 2 enhancins. The sequence analysis revealed the existence of eight homologous regions (hrs) and also suggests processes of gene acquisition by horizontal transfer including the SfGV VG008 ORFs 046/047 (paralogs), 059, 089 and 099. The bioinformatics evidence indicates that the genome donors of mentioned genes could be alpha- and/or betabaculovirus species. The previous reported ability of SfGV VG008 to naturally co-infect the same host with other virus show a possible mechanism to capture genes and thus improve its fitness.

  10. Biological activity of Bt proteins expressed in different structures of transgenic corn against Spodoptera frugiperda

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    Daniel Bernardi

    2016-06-01

    Full Text Available ABSTRACT: Spodoptera frugiperda (J. E. Smith is the main target pest of Bt corn technologies, such as YieldGard VT PRO(tm (Cry1A.105/Cry2Ab2 and PowerCore(tm (Cry1A.105/Cry2Ab2/Cry1F. In this study, it was evaluated the biological activity of Bt proteins expressed in different plant structures of YieldGard VT PRO(tm and PowerCore(tm corn against S. frugiperda . Complete mortality of S. frugiperda neonates was observed on leaf-disc of both Bt corn technologies. However, the mortality in silks and grains was lower than 50 and 6%, respectively. In addition, more than 49% of the surviving larvae in silks and grains completed the biological cycle. However, all life table parameters were negatively affected in insects that developed in silks and grains of both Bt corn events. In summary, the low biological activity of Bt proteins expressed on silks and grains of YieldGard VT PRO(tm and PowerCore(tm corn can contribute to the resistance evolution in S. frugiperda populations.

  11. Spodoptera frugiperda FKBP-46 is a consensus p53 motif binding protein.

    Science.gov (United States)

    Mohareer, Krishnaveni; Sahdev, Sudhir; Hasnain, Seyed E

    2013-04-01

    p53 protein, the central molecule of the apoptosis pathway, is mutated in 50% of the human cancers. Of late, p53 homologues have been identified from different invertebrates including Drosophila melanogaster, Caenorhabditis elegans, Squid, and Clams. We report the identification of a p53-like protein in Spodoptera frugiperda (Sf9) insect cells, which is activated during oxidative stress, caused by exposure to UV-B or H(2) O(2) , and binds to p53 consensus DNA binding motifs as well as other p53 cognate motifs. Sf9 p53 motif-binding protein is similar to murine and Drosophila p53 in terms of molecular size, which is around 50-60 kDa, as evident from UV cross-linking, and displays DNA binding characteristics similar to both insect and vertebrate p53 as seen from electrophoretic mobility shift assays. The N-terminal sequencing of the purified Sf9 p53 motif-binding protein reveals extensive homology to the pro-apoptotic FK-506 binding protein (FKBP-46), earlier identified in Sf9 cells as a factor which interacts with murine casein kinase. FKBP, an evolutionarily conserved protein of mammalian origin functions as a pro-apoptotic factor. Identification of FKBP-46 as a novel p53 motif-binding protein in insect cells adds a new facet to our understanding of the mechanisms of apoptosis under oxidative stress in the absence of a typical p53 homologue.

  12. Use of serological techniques for determination of Spodoptera frugiperda(J E Smith) predators (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Santos-Neto, Joaquim R; Mezencio, Jose M S; Chagas, Aline T A; Michereff-Filho, Miguel; Serrão, José E

    2010-01-01

    Spodoptera frugiperda (J E Smith) is an important pest of several crops, but especially on maize in Brazil. The implementation of biological control measures hinges on the identification of its predators and other natural enemies. As a means of identifying predators, antibodies against S. frugiperda eggs were generated by inoculating rabbits with macerated S. frugiperda eggs, and the production of antibodies against S. frugiperda egg proteins was verifi ed by double immunodiffusion (DID). These antibodies were then utilized in another serological technique, counterimmunoeletrophoresis (CIE), to identify insects that could have ingested S. frugiperda eggs. Macerates of entire insects collected in maize plantations and of individual parts of their digestive tract, including the crop, were the source of antigens in the CIE, while predators fed S. frugiperda eggs in the laboratory served as the control. Antibodies produced by the inoculated rabbits were effective in detecting S. frugiperda egg proteins, especially if crop macerates were used as antigens. Among the species of insects collected from maize plantations, Lagria villosa Fabricius (Coleoptera: Lagriidae) and a species of Lygaeidae (Hemiptera) were identified as possible S. frugiperda predators.

  13. Effects of dietary nickel on detoxification enzyme activities in the midgut of Spodoptera litura Fabricius larvae

    Institute of Scientific and Technical Information of China (English)

    SUN HongXia; ZHOU Qiang; TANG WenCheng; SHU YingHua; ZHANG GuRen

    2008-01-01

    Nickel accumulated in midugt of Spodoptera litura Fabricius could induce the expression of metal-Iothionein, one of the most important detoxification proteins in organisms. In the present study, the effects of dietary nickel on the activities of detoxification enzymes, such as carboxylesterase (CarE) and glutathione S-transferase (GST) in the midgut of S. litura larvae have been studied to get an un-derstanding of the detoxification mechanisms of S. litura larvae to excessive nickel. Results showed that CarE activities in the midgut of the 5th instar larvae decreased at lower levels of nickel (≤5 mg/kg), while increased with increasing nickel doses at higher levels of nickel (≥10 mg/kg) exposure in suc-cessive 3 generations. CarE activities of the 6th instar larvae were also characterized as inhibited at low levels of nickel exposure, and improved at higher levels in the 1st generation. CarE activities of 6th instar larvae in the 2rid and 3rd generations were all lower than that in control. However, GST activities in the midgut of the 5th and 6th instar larvae all increased with increasing nickel doses (1-20 mg/kg) in diets.

  14. An SSH library responsive to azadirachtin A constructed in Spodoptera litura Fabricius cell lines.

    Science.gov (United States)

    Yan, Chao; Zhang, Zhi-Xiang; Xu, Han-Hong

    2012-05-31

    The present study revealed differentially expressed genes responsive to azadirachtin A (Aza) in Spodoptera litura cell line through suppression subtractive hybridization. In the Aza-responsive SSH library, approximately 270 sequences represent 53 different identified genes encoding proteins with various predicted functions, and the percentages of the gene clusters were 26.09% (genetic information processing), 11.41% (cell growth and death), 7.07% (metabolism), 6.52% (signal transduction/transport) and 2.72% (immunity), respectively. Eleven clones homologous to identified genes were selected to be confirmed through quantitative real time polymerase chain reaction. Among the eleven clones validated, all but one transcript of lipase showed an increase in SL cell line collected from ETA, whereas the transcripts of other genes were lower in the SL cell line collected from ETA compared with that of UETA. These genes were considered to be related to the response of SL cell line to Aza. These will provide a new clue to uncover the molecular mechanisms of Aza acting on SL cell line.

  15. Secondary metabolites from Glycine soja and their growth inhibitory effect against Spodoptera litura.

    Science.gov (United States)

    Zhou, Yan-Ying; Luo, Shi-Hong; Yi, Ting-Shuang; Li, Chun-Huan; Luo, Qian; Hua, Juan; Liu, Yan; Li, Sheng-Hong

    2011-06-08

    The wild soybean (Glycine soja Sieb. et Zucc) has been reported to be relatively resistant to insect and pathogenic pests. However, the responsible secondary metabolites in the aerial part of this important plant are largely unknown. From the aerial part of G. soja, 13 compounds were isolated and identified, including seven isoflavonoids (1-7), a cyclitol (8), two sterol derivatives (9 and 10), and three triterpenoids (11-13). Compound 7 is a new isoflavonoid, and compounds 9 and 10 are reported as natural products for the first time. The growth inhibitory activity of 1, 3, 4, and 8 against the larvae of Spodoptera litura was investigated. The most abundant isoflavonoid in the aerial part of G. soja, daidzein (1), which could not be metabolized by S. litura, was found to inhibit the insect larvae growth significantly in 3 days after feeding diets containing the compound. Compounds 3, 4, and 8, which could be partially or completely metabolized, were inactive. Our results suggested that the isoflavonoid daidzein (1) might function as a constitutive defense component in G. soja against insect pests.

  16. Adaptation of an artificial diet for Spodoptera cosmioides (Walk.) (Lepidoptera: Noctuidae) laboratory rearing

    Energy Technology Data Exchange (ETDEWEB)

    Bavaresco, Alvimar [EPAGRI, Estacao Experimetal de Canoinhas, SC (Brazil)]. E-mail: bavaresco@epagri.rct-sc.br; Garcia, Mauro S.; Gruetzmacher, Anderson D.; Ringenberg, Rudiney; Foresti, Josemar [Universidade Federal de Pelotas (UFPel), RS (Brazil). Dept. de Fitossanidade

    2004-03-15

    The biology of Spodoptera cosmioides (Walk.) was studied on three artificial diets with different protein sources (d1 = white bean, yeast extract, soybean flour, powder milk and wheat germ; d2 = 'carioca' bean and yeast extract; d3 = corn flour, wheat germ and yeast extract). The objective of this research was to determine the most suitable diet for mass rearing S. cosmioides in laboratory. The species is highly polyphagous, and for this reason we hypothesized that diets that are suitable for other Lepidoptera can allow its development and fulfill the minimum requirements of biological quality, quantity and economy. Although S. cosmioides has completed the biological cycle on the three diets, the d1 was the most suitable for its rearing and produced the fastest development, higher total survival and pupae weight, as well as higher net reproduction rate (Ro), intrinsic rate of natural increase (rm) and finite rate of natural increase (l). The number of instars varied from six to seven, predominating six in d1 and d3; in d2, half the population presented six instars and half seven. Females presented pupae duration significantly lower that the males in all diets, thus emerging earlier. Adult longevity was not affected by the diets, while total fecundity was higher in d1 and d2. In conclusion, the diet 1 is recommended to mass rearing S. cosmioides in the laboratory. (author)

  17. Electrophysiological and behavioral responses of Spodoptera littoralis caterpillars to attractive and repellent plant volatiles

    Directory of Open Access Journals (Sweden)

    Kacem eRharrabe

    2014-03-01

    Full Text Available In Lepidoptera, the behavior of caterpillars to plant odors is poorly known. However, caterpillars are equipped with a reduced number of olfactory sensilla (3 on the antenna and 4-5 on the maxillary palps which they can use to make fine discrimination between complex plant odors. In this work, we characterized behavioral responses of Spodoptera littoralis larvae to 11 odorants found in plants using binary choices in a Petri dish assay. In this assay, 1-hexanol, hexanal and cis-jasmone elicited a dose-dependent attraction, camphene and eugenol were repellent, while the response to other odorants were less marked. We recorded the electrophysiological responses to 5 of these odors from olfactory neurons of sensillum B2 of the antenna. Several neurons from this sensillum responded to each of the chemicals tested by an increase of their firing activity on top of a high background activity, suggesting that olfactory neurons of caterpillars is broadly tuned to a range of odorants rather than being specialized to a few molecules.

  18. Molecular variability of Spodoptera frugiperda (Lepidoptera: Noctuidae) populations associated to maize and cotton crops in Brazil.

    Science.gov (United States)

    Martinelli, Samuel; Barata, Reinaldo Montrazi; Zucchi, Maria Imaculada; Silva-Filho, Marcio de Castro; Omoto, Celso

    2006-04-01

    The molecular variability among 10 populations of Spodoptera frugiperda (J.E. Smith), collected from maize, Zea mays L., or cotton Gossypium hirsutum L. crops located at distinctive geographical regions in Brazil, was assessed through random amplification of polymorphic DNA (RAPD)-polymerase chain reaction (PCR). In total, 208 RAPD markers were evaluated, and 98% of them were polymorphic. The mean genetic similarity was 0.6621 and 0.2499 by the Simple Matching and Jaccard matrices, respectively. In general, the unweighted pair-group method with arithmetic average dendrograms separated the populations into clusters related to the geographical origin of the samples. No branch of the dendrograms underpinning a molecular association of S. frugiperda has been identified to either of the two host plants. The molecular variance analysis showed that 18 and 82% of the genetic variation was distributed among and within the groups of populations, respectively. The principal coordinate analysis reinforced the pattern of population clustering found with the unweighted pair-group method with arithmetic average method. These results suggest the occurrence of considerable gene flow between S. frugiperda populations from maize and cotton fields located in the same region in Brazil. Therefore, for an effective management of this pest, there is an urgent need for a better understanding of the gene flow of S. frugiperda populations associated to different host plants along the distribution range of this pest over time in a specific cropping system.

  19. Development and Leaf Consumption by Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) Reared on Leaves of Agroenergy Crops.

    Science.gov (United States)

    Cabezas, M F; Nava, D E; Geissler, L O; Melo, M; Garcia, M S; Krüger, R

    2013-12-01

    Spodoptera cosmioides (Walker) (Lepidoptera: Noctuidae) is a polyphagous pest that threatens more than 24 species of crop plants including those used for biodiesel production such as Ricinus communis (castor bean), Jatropha curcas (Barbados nut), and Aleurites fordii (tung oil tree). The development and leaf consumption by S. cosmioides reared on leaves of these three species were studied under controlled laboratory conditions. The egg-to-adult development time of S. cosmioides was shortest when reared on castor bean leaves and longest when reared on tung oil tree leaves. Larvae reared on castor bean and Barbados nut leaves had seven instars, whereas those reared on tung oil tree leaves had eight. Females originating from larvae reared on castor bean and Barbados nut leaves showed greater fecundity than did females originating from larvae reared on tung oil tree leaves. Insects fed on castor bean leaves had shorter life spans than those fed on tung oil tree and Barbados nut leaves although the oviposition period did not differ significantly. The intrinsic and finite rates of increase were highest for females reared on castor bean leaves. Total leaf consumption was highest for larvae reared on tung oil tree leaves and lowest for those reared on Barbados nut leaves. We conclude that castor bean is a more appropriate host plant for the development of S. cosmioides than are Barbados nut and tung oil tree.

  20. Endophyte-mediated interactions between cauliflower, the herbivore Spodoptera litura, and the ectoparasitoid Bracon hebetor.

    Science.gov (United States)

    Kaur, Tamanreet; Singh, Bahaderjeet; Kaur, Amarjeet; Kaur, Sanehdeep

    2015-10-01

    Fungal endosymbionts in plants may influence interactions among plants, herbivores and their parasitoids through the production of secondary metabolites. We used a lepidopteran pest and its generalist parasitoid to test the effect of endophyte-infected plants on a third trophic level. Endophytic fungi, Aspergillus flavus and Aspergillus niger, isolated from Acacia arabica, were used to infect cauliflower plants. We found that the presence of the endophyte in the plants significantly extended the development period of Spodoptera litura (Fab.) larvae. Feeding of the host on endophyte-infected plants further adversely affected the development and performance of its parasitoid, Bracon hebetor (Say). A negative impact was also recorded for longevity and fecundity of endophyte-naive parasitoid females due to the parasitization of host larvae fed on endophyte-infected plants. The presence of endophytes in the diet of the host larvae significantly prolonged the development of the parasitoid. A strong detrimental effect was also recorded for larval survival and emergence of parasitoid adults. The longevity and parasitism rate of female wasps were reduced significantly due to the ingestion of endophyte-infected cauliflower plants by S. litura larvae. Overall, we found that both endophytic fungi had a negative impact on the parasitoid.

  1. Antifeedant activity of an anthraquinone aldehyde in Galium aparine L. against Spodoptera litura F.

    Science.gov (United States)

    Morimoto, Masanori; Tanimoto, Kumiko; Sakatani, Akiko; Komai, Koichiro

    2002-05-01

    The insect antifeedant anthraquinone aldehyde nordamnacanthal (1,3-dihydroxy-anthraquinone-2-al) was identified in Galium aparine L., and isolated from the root powder of akane (Rubia akane), a member of the Rubiaceae. Structure-activity relationship (SAR) studies using a series of anthraquinone analogues suggested that the aldehyde group on the anthraquinone was more important than the quinone moiety for antifeedant activity against the common cutworm (Spodoptera litura). High levels of nordamnacanthal were found in the seed leaf stage and in callus tissue induced from seedlings of G. aparine, but its concentration decreased with plant development. Since these compounds are natural pigments for dying textiles, we also evaluated the antifeedant activity against the carpet beetle (Attagenus japonicus ), a textile pest was also evaluated. While nordamnacanthal had strong antifeedant activity against the common cutworm, it did not show any antifeedant activity against the carpet beetle. The most effective antifeedant against the carpet beetle was the major constituent in the extract of R. trictorum, lucidin-3-O-primeveroside, a food pigment.

  2. Flight attraction of Spodoptera littoralis (Lepidoptera, Noctuidae to cotton headspace and synthetic volatile blends

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    Felipe eBorrero-Echeverry

    2015-06-01

    Full Text Available The insect olfactory system discriminates odor signals of different biological relevance, which drive innate behavior. Identification of stimuli that trigger upwind flight attraction towards host plants is a current challenge, and is essential in developing new, sustainable plant protection methods, and for furthering our understanding of plant-insect interactions. Using behavioral, analytical and electrophysiological studies, we here show that both females and males of the Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera, Noctuidae, use blends of volatile compounds to locate their host plant, cotton, Gossypium hirsutum (Malvales, Malvaceae. Female S. littoralis were engaged in upwind orientation flight in a wind tunnel when headspace collected from cotton plants was delivered through a piezoelectric sprayer. Although males took off towards cotton headspace significantly fewer males than females flew upwind towards the sprayed headspace. Subsequent assays with antennally active synthetic compounds revealed that a blend of nonanal, (Z-3 hexenyl acetate, (E-β-ocimene, and (R-(+-limonene was as attractive as cotton headspace to females and more attractive to males. DMNT and (R-(--linalool, both known plant defense compounds may have reduced the flight attraction of both females and males; more moths were attracted to blends without these two compounds. Our findings provide a platform for further investigations on host plant signals mediating innate behavior, and for the development of novel insect plant protection strategies against S. littoralis.

  3. Oxidative Damage to Spodoptera litura Cell Induced by α-Terthienyl

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-jian; HU Lin; ZHANG Zhi-xiang; XU Han-hong; LIAO Mei-de; LIAO Shao-yu

    2007-01-01

    In this study, the oxidative damage of α-terthienyl (α-T) to the Spodoptera litura (SL) cell and its mechanism were investigated. MTT was used to compare the toxicity of α-T and rotenone to the SL cell. The output of malondialdehyde and relative content of glutathione were determined with 2-thiobarbituric acid (TBA) and 5, 5'-dithio-bis (2-nitrobenzoic acid) (DTNB), respectively. Transmission electron microscope (TEM) was employed to observe the influence of α-T on the membrane and organelle of the SL cell. The result showed that the IC50 value of α-T to the SL cell was 0.21 μg mL-1, whereas the corresponding dose of rotenone was 12.25 μg mL-1. The output of MDA had the same changing tendency with the concentration of α-T, whereas the content of GSH had the negative correlation with it. According to TEM, the cell membrane and karyotheca swelled and couldn't retain integrity, the intracellular substances leaked out, unidentified granules appeared in the SL cell. The mitochondria expanded, and the membrane and subcellular organelle were damaged severely.In this study, it was found that after oxidative damage induced by α-T, the output of MDA increased notably, whereas the relative content of GSH decreased. This indicated that the antioxidant ability of cell weakened. The result of TEM implied that the SL cell suffered from oxidative damage under the appointed dose.

  4. Functional analysis of Spodoptera frugiperda nucleopolyhedrovirus late expression factors in Sf9 cells.

    Science.gov (United States)

    Berretta, Marcelo F; López, M Gabriela; Taboga, Oscar; Sciocco-Cap, Alicia; Romanowski, Víctor

    2013-02-01

    We used transient expression assays to assess the function of the baculovirus Spodoptera frugiperda M nucleopolyhedrovirus (SfMNPV) homologs of Autographa californica MNPV (AcMNPV) factors involved in late gene expression (lefs), in the Sf9 insect cell-line, which is permissive for both viruses. It is well-established that nineteen AcMNPV lefs support optimal levels of activity from a late promoter-reporter gene cassette in this assay. A subgroup of SfMNPV lefs predicted to function in transcription-specific events substituted the corresponding AcMNPV lefs very efficiently. When all SfMNPV lefs were assayed, including replication lefs, activity was low, but addition of two AcMNPV lefs not encoded in SfMNPV genome, resulted in augmented reporter activity. SfMNPV IE-1 was able to activate an early promoter cis-linked to an hr-derived element from SfMNPV but not from AcMNPV. However, the level of early promoter activation with SfMNPV IE-1 was lower compared to AcMNPV IE-1.

  5. A COMPREHENSIVE STUDY ON APOPTOSIS INDUCTION BY AZADIRACHTIN IN Spodoptera frugiperda CULTURED CELL LINE Sf9.

    Science.gov (United States)

    Shu, Benshui; Wang, Wenxiang; Hu, Qingbo; Huang, Jingfei; Hu, Meiying; Zhong, Guohua

    2015-07-01

    The induction of apoptosis by azadirachtin, a well-known botanical tetranortriterpenoid isolated from the neem tree (Azadirachta indica A. Juss) and other members of the Meliaceae, was investigated in Spodoptera frugiperda cultured cell line (Sf9). Morphological changes in Sf9 cells treated by various concentrations of azadirachtin were observed at different times under light microscopy. Morphological and biochemical analysis indicated that Sf9 cells treated by 1.5 μg/mL azadirachtin showed typical morphological changes, which were indicative of apoptosis and a clear DNA ladder. The flow cytometry analysis showed the apoptosis rate reached a maximum value of 32.66% at 24 h with 1.5 μg/mL azadirachtin in Sf9 cells. The inhibition of Sf9 cell proliferation suggested that the effect of azadirachtin was dose dependent and the EC50 at 48 and 72 h was 2.727 × 10(-6) and 6.348 × 10(-9) μg/mL, respectively. The treatment of azadirachtin in Sf9 cells could significantly increase the activity of Sf caspase-1, but showed no effect on the activity of Topo I, suggesting that the apoptosis induced by azadirachtinin Sf9 cells is through caspase-dependent pathway. These results provided not only a series of morphological, biochemical, and toxicological comprehensive evidences for induction of apoptosis by azadirachtin, but also a reference model for screening insect cell apoptosis inducers from natural compounds.

  6. Quantitative proteomics of Spodoptera frugiperda cells during growth and baculovirus infection.

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    Nuno Carinhas

    Full Text Available Baculovirus infection of Spodoptera frugiperda cells is a system of choice to produce a range of recombinant proteins, vaccines and, potentially, gene therapy vectors. While baculovirus genomes are well characterized, the genome of S. frugiperda is not sequenced and the virus-host molecular interplay is sparsely known. Herein, we describe the application of stable isotope labeling by amino acids in cell culture (SILAC to obtain the first comparative proteome quantitation of S. frugiperda cells during growth and early baculovirus infection. The proteome coverage was maximized by compiling a search database with protein annotations from insect species. Of interest were differentially proteins related to energy metabolism, endoplasmic reticulum and oxidative stress, yet not investigated in the scope of baculovirus infection. Further, the reduced expression of key viral-encoded proteins early in the infection cycle is suggested to be related with decreased viral replication at high cell density culture. These findings have implications for virological research and improvement of baculovirus-based bioprocesses.

  7. The Complete Sequence of the First Spodoptera frugiperda Betabaculovirus Genome: A Natural Multiple Recombinant Virus

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    Paola E. Cuartas

    2015-01-01

    Full Text Available Spodoptera frugiperda (Lepidoptera: Noctuidae is a major pest in maize crops in Colombia, and affects several regions in America. A granulovirus isolated from S. frugiperda (SfGV VG008 has potential as an enhancer of insecticidal activity of previously described nucleopolyhedrovirus from the same insect species (SfMNPV. The SfGV VG008 genome was sequenced and analyzed showing circular double stranded DNA of 140,913 bp encoding 146 putative ORFs that include 37 Baculoviridae core genes, 88 shared with betabaculoviruses, two shared only with betabaculoviruses from Noctuide insects, two shared with alphabaculoviruses, three copies of own genes (paralogs and the other 14 corresponding to unique genes without representation in the other baculovirus species. Particularly, the genome encodes for important virulence factors such as 4 chitinases and 2 enhancins. The sequence analysis revealed the existence of eight homologous regions (hrs and also suggests processes of gene acquisition by horizontal transfer including the SfGV VG008 ORFs 046/047 (paralogs, 059, 089 and 099. The bioinformatics evidence indicates that the genome donors of mentioned genes could be alpha- and/or betabaculovirus species. The previous reported ability of SfGV VG008 to naturally co-infect the same host with other virus show a possible mechanism to capture genes and thus improve its fitness.

  8. Adequação de uma dieta artificial para os biótipos "milho" e "arroz" de Spodoptera frugiperda (Lepidoptera: Noctuidae) Adaptation of an artificial diet for the biotypes "corn" and "rice" of Spodoptera frugiperda (Lepidoptera: Noctuidae)

    OpenAIRE

    Gustavo Rossato Busato; Mauro Silveira Garcia; Alci Enimar Loeck; Marcelo Zart; Adrise Medeiros Nunes; Oderlei Bernardi; Fabiana da Silva Andersson

    2006-01-01

    Spodoptera frugiperda é considerada uma das principais pragas da cultura do milho (lagarta-do-cartucho) e do arroz irrigado (lagarta-da-folha), ocasionando altos índices de desfolhamento. O objetivo do estudo foi obter uma dieta artificial adequada para criar os biótipos "milho" e "arroz" de S. frugiperda (J.E. Smith), em laboratório. Os insetos foram coletados em áreas cultivadas com milho e arroz irrigado no ecossistema de várzea e a identificação foi realizada pela análise do DNA genômico....

  9. Characterization of native Bacillus thuringiensis strains and selection of an isolate active against Spodoptera frugiperda and Peridroma saucia.

    Science.gov (United States)

    Alvarez, Analía; Virla, Eduardo G; Pera, Licia M; Baigorí, Mario D

    2009-12-01

    Twelve Bacillus thuringiensis (Bt) strains, isolated from larvae and soil samples in Argentina, were molecularly and phenotypically characterized and their insecticidal activities against Spodoptera frugiperda and Peridroma saucia were determined. One isolate--Bt RT--produced more than 93% mortality on first instar larvae of both species, which was higher than that produced by the reference strain Bt 4D1. Bt RT carried a different cry gene profile than Bt 4D1. Scanning electron microscopy showed the presence of bipyramidal and cuboidal crystals. Phenotypic characterization revealed lytic enzymes that could contribute to Bt pathogenicity.

  10. Chemical constituents of methanolic extracts of Jatropha curcas L and effects on Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae)

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Sandra Santos; Silva, Thanany Brasil da; Moraes, Valeria Regina de Souza; Nogueira, Paulo Cesar de Lima; Costa, Emmanoel Vilaca [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil). Dept. de Quimica; Bernardo, Antonio Rogerio; Matos, Andreia Pereira; Fernandes, Batista; Silva, Maria Fatima das Gracas Fernandes da [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica; Pessoa, Angela Maria dos Santos; Silva-Mann, Renata, E-mail: djbf@ufscar.br [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil). Dept. de Engenharia Agronomica

    2012-07-01

    The biological activity of seven extracts from leaves of different Jatropha curcas L (Euphorbiaceae) accessions was evaluated on Spodoptera frugiperda. Methanol extracts were incorporated into an artificial diet and offered to the larval stage of S. frugiperda. The parameters evaluated were length of larval and pupal stages, mortality of larval and total cycle stage, and weight of pupae. The extracts of the EMB accessions showed the best result for larval mortality at 60.00 and 56.67%, compared with the control, respectively. Hexane partition of the methanol extract of the leaves of PM-14 accessions allowed the identification of phytosterols, phytol and n-alkanols. (author)

  11. Interaction of Bacillus thuringiensis Vegetative Insecticidal Protein with Ribosomal S2 Protein Triggers Larvicidal Activity in Spodoptera frugiperda▿ †

    OpenAIRE

    Singh, Gatikrushna; Sachdev, Bindiya; Sharma, Nathilal; Seth, Rakesh; Bhatnagar, Raj K.

    2010-01-01

    Vegetative insecticidal protein (Vip3A) is synthesized as an extracellular insecticidal toxin by certain strains of Bacillus thuringiensis. Vip3A is active against several lepidopteran pests of crops. Polyphagous pest, Spodoptera frugiperda, and its cell line Sf21 are sensitive for lyses to Vip3A. Screening of cDNA library prepared from Sf21 cells through yeast two-hybrid system with Vip3A as bait identified ribosomal protein S2 as a toxicity-mediating interacting partner protein. The Vip3A-r...

  12. Capacidade Predatória de Euborellia annulipes (Lucas, 1847 sobre Spodoptera frugiperda (Smith, 1797 = Predatory Capacity of Euborellia annulipes (Lucas, 1847 on Spodoptera frugiperda (Smith, 1797

    Directory of Open Access Journals (Sweden)

    Aldeni Barbosa da Silva

    2009-01-01

    Full Text Available Estudou-se a Capacidade Predatória de Euborellia annulipes sobre Spodoptera frugiperda em laboratório. O estudo foi conduzido no Laboratório de Entomologia do Setor de Fitossanidade da Universidade Federal da Paraíba (UFPB à temperatura de 25 ± 1ºC, umidade relativa de 70 + 10% e fotofase de 12h. Notou-se consumo crescente de ovos,podendo ser observado consumo diário médio de 11,06, 49,02, 122,7, 148,09 e 374,9 ovos, do 1° ao 5° instar, respectivamente. A capacidade predatória sobre lagartas de 1° instar de S. frugiperda aumentou de acordo com o seu desenvolvimento, com aumento de,aproximadamente, 14,3 vezes do 1° ao 5° instar, nos dez dias de consumo, sendo que, o 4° e o 5° instares apresentaram consumo diário médio de 25,5 e 26,6, respectivamente, bem superior em comparação aos demais instares; o maior consumo de lagartas de 2º instar pelopredador, ocorreu no 4º e 5º instar, que apresentaram consumo diário médio de 12,8 e 15,1, respectivamente. Verifica-se que E. annulipes demonstra ser predador potencial de ovos e lagartas de S. frugiperda, chegando um adulto a consumir 1.481,2; 89,20 e 48,6 ovos e lagartasde 1º e 2º instares, respectivamente, nos dez dias de consumo.The predatory capacity of Euborellia annulipes on Spodopterafrugiperda was studied in a laboratory setting. The study was conducted in the Laboratory of Entomology of the Division of Plant Protection, Federal University of Paraíba (UFPB at a temperature of 25 ± 1°C, relative humidity of 70 + 10% and a 12-hour photophase. Thestudy detected growing egg intake, with an average daily consumption of 11.06, 49.02, 122.7, 148.09 and 374.9 eggs, from the first to the fifth instars, respectively. A predatory capacity of fist-instar larvae of S. frugiperda increased in line with its development, with an increase of approximately 14.3 times from the first to the fifth instar, in the 10 days of consumption, whereas the fourth and fifth instars presented an

  13. Parasitism capacity of Telenomus remus Nixon (Hymenoptera: Scelionidae on Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae eggs

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    Regiane Cristina Oliveira de Freitas Bueno

    2010-02-01

    Full Text Available This work studied the parasitism capacity of Telenomus remus Nixon (Hymenoptera: Scelionidae on Spodoptera frugiperda (Smith (Hymenoptera: Scelionidae eggs at 15, 20, 25, 28, 31, and 35°C, aiming to use this natural enemy in biological control programs in crops where S. frugiperda was considered pest. The parasitism during the first 24 h was 60.90, 81.65, 121.05, 117.55 and 108.55 parasited eggs per female from egg masses of approximately 150 eggs, at 15, 20, 25, 28 and 31°C, respectively. Females of T. remus reached parasitism higher than 80% at 15, 20, 25, 28 and 31ºC at 5, 27, 8, 2, and 2 days, respectively. At 35ºC, there was no parasitism. The highest parasitism rates occurred at 20, 25, 28 and 31°C. T. remus female longevity varied from 15.7 to 7.7 days from 15 to 31°C. The highest tested temperature (35°C was inappropriate for T. remus development. At that temperature, female longevity was greatly reduced (1.7±0.02 and egg viability was null. All T. remus survival curves were of type I, which showed an increase in mortality rate with time.Este trabalho estudou a capacidade de parasitismo de Telenomus remus Nixon (Hymenoptera: Scelionidae em ovos de Spodoptera frugiperda (Smith (Hymenoptera: Scelionidae nas temperaturas de 15, 20, 25, 28, 31 e 35ºC objetivando usar esse inimigo natural em programas de controle biológico em culturas onde S. frugiperda é considerada praga. O parasitismo ocorrido nas primeiras 24 h foi de 60,90; 81,65; 121,05; 117,55 e 108,55 ovos parasitados por fêmea em massas ovos com aproximadamente 150 ovos, nas temperaturas de 15, 20, 25, 28 e 31ºC. Fêmeas de T. remus causaram mais de 80% do parasitismo dos ovos nas temperaturas de 15, 20, 25, 28 e 31ºC aos 5, 27, 8, 2 e 2 dias, respectivamente. Na temperatura de 35ºC não houve parasitismo. As maiores taxas de parasitismo ocorreram nas temperaturas de 20, 25, 28 e 31ºC. A longevidade média de fêmeas de T. remus nas temperaturas compreendidas entre 15

  14. Compartmentalization of oxidative stress and antioxidant defense in the larval gut of Spodoptera littoralis.

    Science.gov (United States)

    Krishnan, Natraj; Sehnal, Frantisek

    2006-09-01

    Allelochemicals play important roles in the plant defense against herbivorous insects. They act as feeding deterrents, interfere with digestion and nutrient absorption, and cause production of potentially dangerous oxidative radicals. This study demonstrates that the distributions of oxidative radicals and of the antioxidant enzymes that eliminate them are compartmentalized in the digestive tract of Spodoptera littoralis larvae. Feeding on diets supplemented with the tannic acid (TA), alpha-solanine, and demissidine, respectively, did not affect the rate of food passage through the digestive tract of larvae but 1.25, 2.5, and 5% TA evoked a strong oxidative response. The amount of the superoxide anion in the foregut tissue and content increased up to 70-fold and the titer of total peroxides in the foregut content about 3-fold. This oxidative stress was associated with enhanced carbonyl content in the foregut tissue proteins, indicative of certain tissue deterioration. Extensive foregut damage was probably prevented by elevated activity of the glutathione S-transferase peroxidase. A complex antioxidant response was elicited in the midgut. The activities of superoxide dismutase and catalase increased significantly in the midgut tissue and content, and the activity of ascorbate peroxidase rose in the midgut tissue. The enzymes apparently eliminated oxidative radicals passing to midgut from the foregut with the food bolus and thereby prevented carbonylation of the midgut proteins. We postulate that the generation of oxidative radicals in the foregut and the induction of antioxidant defense in the midgut are controlled processes and that their compartmentalization is an important functional feature of the digestive tract. The glycoalkaloid alpha-solanine and the aglycone demissidine applied at 0.05 and 0.1% concentrations had no effect on any of the examined parameters.

  15. Effects of green manure cover crops on Spodoptera litura (Lepidoptera: Noctuidae) populations.

    Science.gov (United States)

    Tuan, Shu-Jen; Li, Nian-Jhen; Yeh, Chih-Chun; Tang, Li-Cheng; Chi, Hsin

    2014-06-01

    Spodoptera litura (F.) is an important pest of numerous agro-economic crops, including green manure cover crops. In Taiwan, sesbania (Sesbanin roxburghii Merr.), sunn hemp (Crotalaria juncea L.), and rapeseed (Brassicae campestris L. variety chinensis) are the most popular green manure crops; sesbania and sunn hemp are commonly planted in warm seasons, whereas rapeseed is grown in the winter. In this study, life-table data for S. litura reared on these three green manures were collected to evaluate their roles as refuges of this pest. The net reproductive rate, intrinsic rate of increase, and finite rate of increase of S. litura were the highest when reared on sesbania (1428.1 offspring, 0.2327 d(-1), 1.2621 d(-1)), followed by sunn hemp (778.4 offspring, 0.2070 d(-1), 1.2300 d(-1)) and rapeseed (737.6 offspring, 0.2040 d(-1), 1.2263 d(-1)). The high growth rates on these green manure crops show that they can serve as potential breeding sites for S. litura. Population projection demonstrated the rapid growth of S. litura on sesbania, sunn hemp, and rapeseed as well. Because most growers have traditionally ignored pest management in green manure fields, the mass emergence of S. litura in these fields may cause unexpected infestations in nearby vegetable, corn, and peanut crops. This study shows that the use of green manures as sources of nutrients should be critically reassessed and an area-wide pest management program should be instituted by taking the population of S. litura in green manure fields into consideration.

  16. Avaliação de cultivares de amendoim para resistência a Spodoptera frugiperda

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    Aniele Pianoscki de Campos

    2011-01-01

    Full Text Available Este trabalho teve por objetivo identificar cultivares de amendoim com resistência a Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae, determinando os graus de resistência por meio da análise univariada e multivariada. Utilizaram-se cultivares de amendoim de hábitos de crescimento ereto (IAC 5, IAC 8112, IAC 22 e IAC Tatu ST e rasteiro (IAC 503, IAC 505, IAC 147, IAC 125, IAC Caiapó e IAC Runner 886, semeadas em campo. Lagartas de primeiro ínstar foram individualizadas em placas de Petri forradas com papel filtro umedecido e mantidas sob condições controladas de temperatura (25 ± 2 °C, umidade (60 ± 10% e fotofase (12 horas. Utilizaram-se cinco repetições de dez lagartas (recém-eclodidas, em delineamento inteiramente casualizado. Diariamente, foram fornecidos folíolos novos, lavados com solução de hipoclorito de sódio a 1%. Avaliaram-se a duração (dias, a massa (mg e a viabilidade (% dos períodos larval e pupal, a razão sexual, longevidade e fecundidade. Os dados foram submetidos à análise de variância (teste F e as médias comparadas pelo teste de Tukey (p<0,05, além da análise de agrupamento e de componentes principais. As cultivares de hábito de crescimento ereto, IAC 22, e rasteiro, IAC Runner 886, foram menos adequadas ao desenvolvimento do inseto, interferindo nas fases larval e pupal de S. frugiperda, demonstrando resistência moderada do tipo antibiose.

  17. Geographic variation in cypermethrin insecticide resistance and morphometry in Spodoptera litura (Fabricius) (Lepidoptera:Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    Anbalagan Santhosh Kumar; Kathirvelu Baskar; Ajith Johnson; Savarior Vincent

    2014-01-01

    Objective: To find out the most resistant strain of Spodoptera litura (S. litura) from Tamil Nadu, Kerala and Karnataka by synthetic insecticide treatment. Methods:Using leaf disc no-choice method, the insects were tested with different doses for pesticides. The LC50 and LC90 values were calculated by probit analysis. Results:In the insect bioassay, the cypermethrin insecticide showed significantly higher LC50 values of 14.699 g/L and 15.738 g/L against the Tamil Nadu and Kerala S. litura insect cultures respectively. The body length of 2nd, 3rd and 4th instar larvae were significantly higher (P≤0.05) in TTP insect population [(19.2±2.3) mm, (28.05±3.20) mm, (36.1±2.0) mm], when compared with KTK [(18.5±2.7) mm, (23.38±2.00) mm, (31.75±2.70) mm] and control, KBB [(15.65±2.30) mm, (23.65±2.70) mm, (33.2±2.2) mm] populations. The body breadth of 3rd instar larvae was significantly higher (P≤0.05) in TTP insect population (4.9±1.1) mm, when compared with KTK (3.93±0.80) mm and control, KBB (3.65±0.70) mm populations. Conclusions: The present study clearly showed that field collected strains were highly resistant when compared to control. Based on our study, we conclude that reduced use of synthetic pesticides is necessary and IPM is a better way to reduce the development of pesticide resistance among strains of S. litura.

  18. Effects of Pyriproxyfen on Female Reproduction in the Common Cutworm, Spodoptera litura (F. (Lepidoptera: Noctuidae.

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    Qi Xu

    Full Text Available The common cutworm, Spodoptera litura, is a rapidly reproducing pest of numerous agricultural ecosystems worldwide. The use of pesticides remains the primary means for controlling S. litura, despite their negative ecological impact and potential threat to human health. The use of exogenous hormone analogs may represent an alternative to insecticides. Juvenile hormones (JHs play an important role in the reproductive systems of female insects, but the effects of pyriproxyfen, a JH analog, on reproduction in S. litura were poorly understood. In this paper, we topically treated the newly emerged females with 20, 60, or 100 μg of pyriproxyfen to determine its effects on reproduction. Then, we examined the expression of vitellogenin (Vg and three hormone receptors, USP, HR3, and EcR, using quantitative reverse transcription and real-time polymerase chain reaction (qRT-PCR, and found that pyriproxyfen up-regulated the expression of Vg, USP, and HR3, whereas the expression of EcR was unaffected. An analysis of fecundity showed that the peak oviposition day, lifespan, and oviposition period were progressively shortened as the pyriproxyfen dosage increased. We also found that pyriproxyfen decreased egg laying amount, whereas the number of mature eggs that remained in the ovarioles of dead females increased as the pyriproxyfen dosage increased. We examined oocytes using transmission electron microscopy and found that treatment with 100 μg of pyriproxyfen increased the metabolism by increasing the amount of rough endoplasmic reticulum and mitochondria in the primary oocytes. Our results suggest that the topical application of pyriproxyfen on newly emerged females can efficiently reduce reproduction in S. litura and may represent an alternative to the use of insecticides for controlling the agricultural pest.

  19. Effects of Pyriproxyfen on Female Reproduction in the Common Cutworm, Spodoptera litura (F.) (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Xu, Qi; Tang, Bin; Zou, Qi; Zheng, Huizhen; Liu, Xiaojun; Wang, Shigui

    2015-01-01

    The common cutworm, Spodoptera litura, is a rapidly reproducing pest of numerous agricultural ecosystems worldwide. The use of pesticides remains the primary means for controlling S. litura, despite their negative ecological impact and potential threat to human health. The use of exogenous hormone analogs may represent an alternative to insecticides. Juvenile hormones (JHs) play an important role in the reproductive systems of female insects, but the effects of pyriproxyfen, a JH analog, on reproduction in S. litura were poorly understood. In this paper, we topically treated the newly emerged females with 20, 60, or 100 μg of pyriproxyfen to determine its effects on reproduction. Then, we examined the expression of vitellogenin (Vg) and three hormone receptors, USP, HR3, and EcR, using quantitative reverse transcription and real-time polymerase chain reaction (qRT-PCR), and found that pyriproxyfen up-regulated the expression of Vg, USP, and HR3, whereas the expression of EcR was unaffected. An analysis of fecundity showed that the peak oviposition day, lifespan, and oviposition period were progressively shortened as the pyriproxyfen dosage increased. We also found that pyriproxyfen decreased egg laying amount, whereas the number of mature eggs that remained in the ovarioles of dead females increased as the pyriproxyfen dosage increased. We examined oocytes using transmission electron microscopy and found that treatment with 100 μg of pyriproxyfen increased the metabolism by increasing the amount of rough endoplasmic reticulum and mitochondria in the primary oocytes. Our results suggest that the topical application of pyriproxyfen on newly emerged females can efficiently reduce reproduction in S. litura and may represent an alternative to the use of insecticides for controlling the agricultural pest.

  20. Molecular cloning and characterization of the α-glucosidase II from Bombyx mori and Spodoptera frugiperda.

    Science.gov (United States)

    Watanabe, Satoko; Kakudo, Akemi; Ohta, Masato; Mita, Kazuei; Fujiyama, Kazuhito; Inumaru, Shigeki

    2013-04-01

    The α-glucosidase II (GII) is a heterodimer of α- and β-subunits and important for N-glycosylation processing and quality control of nascent glycoproteins. Although high concentration of α-glucosidase inhibitors from mulberry leaves accumulate in silkworms (Bombyx mori) by feeding, silkworm does not show any toxic symptom against these inhibitors and N-glycosylation of recombinant proteins is not affected. We, therefore, hypothesized that silkworm GII is not sensitive to the α-glucosidase inhibitors from mulberry leaves. However, the genes for B. mori GII subunits have not yet been identified, and the protein has not been characterized. Therefore, we isolated the B. mori GII α- and β-subunit genes and the GII α-subunit gene of Spodoptera frugiperda, which does not feed on mulberry leaves. We used a baculovirus expression system to produce the recombinant GII subunits and identified their enzyme characteristics. The recombinant GII α-subunits of B. mori and S. frugiperda hydrolyzed p-nitrophenyl α-d-glucopyranoside (pNP-αGlc) but were inactive toward N-glycan. Although the B. mori GII β-subunit was not required for the hydrolysis of pNP-αGlc, a B. mori GII complex of the α- and β-subunits was required for N-glycan cleavage. As hypothesized, the B. mori GII α-subunit protein was less sensitive to α-glucosidase inhibitors than was the S. frugiperda GII α-subunit protein. Our observations suggest that the low sensitivity of GII contributes to the ability of B. mori to evade the toxic effect of α-glucosidase inhibitors from mulberry leaves.

  1. Fitness costs associated with field-evolved resistance to Bt maize in Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Jakka, S R K; Knight, V R; Jurat-Fuentes, J L

    2014-02-01

    Increasing adoption of transgenic crops expressing cry toxin genes from Bacillus thuringiensis (Bt crops) represents an augmented risk for development of insect resistance. While fitness costs can greatly influence the rate of resistance evolution, most available data related to Bt resistance have been obtained from laboratory-selected insect strains. In this article, we test the existence of fitness costs associated with high levels of field-evolved resistance to Bt maize event TC1507 in a strain of Spodoptera frugiperda (JE Smith) originated from maize fields in Puerto Rico. Fitness costs in resistant S. frugiperda were evaluated by comparing biological performance to susceptible insects when reared on meridic diet, maize or soybean leaf tissue, or cotton reproductive tissues. Parameters monitored included larval survival, larval and pupal weights, developmental time (larval and pupal), adult longevity, reproductive traits (fecundity and fertility), and sex ratio. We found that all monitored parameters were influenced to a similar extent by the host, independently of susceptibility to Bt maize. The only parameter that significantly differed between strains for all hosts was a longer larval developmental period in resistant S. frugiperda, which resulted in emergence asynchrony between susceptible and resistant adults. To test the relevance of fitness costs in resistant S. frugiperda, we performed a selection experiment to monitor the stability of resistance in a heterogeneous strain through 12 generations of rearing on meridic diet. Our data demonstrate lack of fitness costs relevant to stability of field-evolved resistance to Bt maize and help explain reported stability of field-evolved resistance in Puerto Rican populations of S. frugiperda.

  2. Spodoptera frugiperda (Lepidoptera: Noctuidae) host-plant variants: two host strains or two distinct species?

    Science.gov (United States)

    Dumas, Pascaline; Legeai, Fabrice; Lemaitre, Claire; Scaon, Erwan; Orsucci, Marion; Labadie, Karine; Gimenez, Sylvie; Clamens, Anne-Laure; Henri, Hélène; Vavre, Fabrice; Aury, Jean-Marc; Fournier, Philippe; Kergoat, Gael J; d'Alençon, Emmanuelle

    2015-06-01

    The moth Spodoptera frugiperda is a well-known pest of crops throughout the Americas, which consists of two strains adapted to different host-plants: the first feeds preferentially on corn, cotton and sorghum whereas the second is more associated with rice and several pasture grasses. Though morphologically indistinguishable, they exhibit differences in their mating behavior, pheromone compositions, and show development variability according to the host-plant. Though the latter suggest that both strains are different species, this issue is still highly controversial because hybrids naturally occur in the wild, not to mention the discrepancies among published results concerning mating success between the two strains. In order to clarify the status of the two host-plant strains of S. frugiperda, we analyze features that possibly reflect the level of post-zygotic isolation: (1) first generation (F1) hybrid lethality and sterility; (2) patterns of meiotic segregation of hybrids in reciprocal second generation (F2), as compared to the meiosis of the two parental strains. We found a significant reduction of mating success in F1 in one direction of the cross and a high level of microsatellite markers showing transmission ratio distortion in the F2 progeny. Our results support the existence of post-zygotic reproductive isolation between the two laboratory strains and are in accordance with the marked level of genetic differentiation that was recovered between individuals of the two strains collected from the field. Altogether these results provide additional evidence in favor of a sibling species status for the two strains.

  3. Cecropins as a marker of Spodoptera frugiperda immunosuppression during entomopathogenic bacterial challenge.

    Science.gov (United States)

    Duvic, B; Jouan, V; Essa, N; Girard, P-A; Pagès, S; Abi Khattar, Z; Volkoff, N-A; Givaudan, A; Destoumieux-Garzon, D; Escoubas, J-M

    2012-06-01

    An antimicrobial peptide (AMP) of the cecropin family was isolated by HPLC from plasma of the insect pest, Spodoptera frugiperda. Its molecular mass is 3910.9 Da as determined by mass spectrometry. Thanks to the EST database Spodobase, we were able to describe 13 cDNAs encoding six different cecropins which belong to the sub-families CecA, CecB, CecC and CecD. The purified peptide identified as CecB1 was chemically synthesized (syCecB1). It was shown to be active against Gram-positive and Gram-negative bacteria as well as fungi. Two closely related entomopathogenic bacteria, Xenorhabdus nematophila F1 and Xenorhabdus mauleonii VC01(T) showed different susceptibility to syCecB1. Indeed, X. nematophila was sensitive to syCecB1 whereas X. mauleonii had a minimal inhibitory concentration (MIC) eight times higher. Interestingly, injection of live X. nematophila into insects did not induce the expression of AMPs in hemolymph. This effect was not observed when this bacterium was heat-killed before injection. On the opposite, both live and heat-killed X. mauleonii induced the expression of AMPs in the hemolymph of S. frugiperda. The same phenomenon was observed for another immune-related protein lacking antimicrobial activity. Altogether, our data suggest that Xenorhabdus strains have developed different strategies to supplant the humoral defense mechanisms of S. frugiperda, either by increasing their resistance to AMPs or by preventing their expression during such host-pathogen interaction.

  4. Genomic Analysis and Isolation of RNA Polymerase II Dependent Promoters from Spodoptera frugiperda.

    Science.gov (United States)

    Bleckmann, Maren; Fritz, Markus H-Y; Bhuju, Sabin; Jarek, Michael; Schürig, Margitta; Geffers, Robert; Benes, Vladimir; Besir, Hüseyin; van den Heuvel, Joop

    2015-01-01

    The Baculoviral Expression Vector System (BEVS) is the most commonly used method for high expression of recombinant protein in insect cells. Nevertheless, expression of some target proteins--especially those entering the secretory pathway--provides a severe challenge for the baculovirus infected insect cells, due to the reorganisation of intracellular compounds upon viral infection. Therefore, alternative strategies for recombinant protein production in insect cells like transient plasmid-based expression or stable expression cell lines are becoming more popular. However, the major bottleneck of these systems is the lack of strong endogenous polymerase II dependent promoters, as the strong baculoviral p10 and polH promoters used in BEVS are only functional in presence of the viral transcription machinery during the late phase of infection. In this work we present a draft genome and a transcriptome analysis of Sf21 cells for the identification of the first known endogenous Spodoptera frugiperda promoters. Therefore, putative promoter sequences were identified and selected because of high mRNA level or in analogy to other strong promoters in other eukaryotic organism. The chosen endogenous Sf21 promoters were compared to early viral promoters for their efficiency to trigger eGFP expression using transient plasmid based transfection in a BioLector Microfermentation system. Furthermore, promoter activity was not only shown in Sf21 cells but also in Hi5 cells. The novel endogenous Sf21 promoters were ranked according to their activity and expand the small pool of available promoters for stable insect cell line development and transient plasmid expression in insect cells. The best promoter was used to improve plasmid based transient transfection in insect cells substantially.

  5. Biology and nutrition of Spodoptera frugiperda (Lepidoptera: Noctuidae fed on different food sources

    Directory of Open Access Journals (Sweden)

    Débora Mello da Silva

    Full Text Available ABSTRACT: We studied Spodoptera frugiperda development using different food sources in the laboratory and field. Newly hatched larvae were fed soybean, cotton, maize, wheat, and oat leaves. An artificial diet was used as the control. Duration of pre-pupal, pupal, and larva-adult period, pupal weight, sex ratio, survival, larva feeding preferences, oviposition preferences, and nutritional quality of different hosts were evaluated. Insects fed on wheat showed the shortest larva-adult period. The insects fed on cotton and soybean had longer larval development cycles and pupae of lower weight. Feeding preference was evident for third instar larvae and did not differ between wheat, oat, maize, and soybean, which were the preferred hosts. Moths oviposited to a greater extent on the upper canopy of wheat than that of other plants in both the no-choice and free-choice tests. Treatments influenced insect growth, food consumption, and digestion when nutritional variables were analyzed. Thus, grasses were better hosts for S. frugiperda development. Cotton was the least preferred food, followed by soybean. The present study can improve our understanding of S. frugiperda in these different crops and help in developing management strategies. Even though S. frugiperda is considered to be polyphagous, this pest is closely associated with grasses (maize, wheat, oat and has lower potential as a soybean or cotton feeder. Howerver, S. frugiperda food intake regulation appears to be triggered by a complex of different mechanisms. Thus, S. frugiperda can also damage soybean and cotton and adapt to them in the absence of preferred hosts.

  6. Characterization of an antennal carboxylesterase from the pest moth Spodoptera littoralis degrading a host plant odorant.

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    Nicolas Durand

    Full Text Available BACKGROUND: Carboxyl/cholinesterases (CCEs are highly diversified in insects. These enzymes have a broad range of proposed functions, in neuro/developmental processes, dietary detoxification, insecticide resistance or hormone/pheromone degradation. As few functional data are available on purified or recombinant CCEs, the physiological role of most of these enzymes is unknown. Concerning their role in olfaction, only two CCEs able to metabolize sex pheromones have been functionally characterized in insects. These enzymes are only expressed in the male antennae, and secreted into the lumen of the pheromone-sensitive sensilla. CCEs able to hydrolyze other odorants than sex pheromones, such as plant volatiles, have not been identified. METHODOLOGY: In Spodoptera littoralis, a major crop pest, a diversity of antennal CCEs has been previously identified. We have employed here a combination of molecular biology, biochemistry and electrophysiology approaches to functionally characterize an intracellular CCE, SlCXE10, whose predominant expression in the olfactory sensilla suggested a role in olfaction. A recombinant protein was produced using the baculovirus system and we tested its catabolic properties towards a plant volatile and the sex pheromone components. CONCLUSION: We showed that SlCXE10 could efficiently hydrolyze a green leaf volatile and to a lesser extent the sex pheromone components. The transcript level in male antennae was also strongly induced by exposure to this plant odorant. In antennae, SlCXE10 expression was associated with sensilla responding to the sex pheromones and to plant odours. These results suggest that a CCE-based intracellular metabolism of odorants could occur in insect antennae, in addition to the extracellular metabolism occurring within the sensillar lumen. This is the first functional characterization of an Odorant-Degrading Enzyme active towards a host plant volatile.

  7. Herbivore-induced maize leaf volatiles affect attraction and feeding behaviour of Spodoptera littoralis caterpillars

    Directory of Open Access Journals (Sweden)

    Georg E. von Mérey

    2013-06-01

    Full Text Available Plants under herbivore attack emit volatile organic compounds (VOCs that can serve as foraging cues for natural enemies. Adult females of Lepidoptera, when foraging for host plants to deposit eggs, are commonly repelled by herbivore-induced VOCs, probably to avoid competition and natural enemies. Their larval stages, on the other hand, have been shown to be attracted to inducible VOCs. We speculate that this contradicting behaviour of lepidopteran larvae is due to a need to quickly find a new suitable host plant if they have fallen to the ground. However, once they are on a plant they might avoid the sites with fresh damage to limit competition and risk of cannibalism by conspecifics, as well as exposure to natural enemies. To test this we studied the effect of herbivore-induced VOCs on the attraction of larvae of the moth Spodoptera littoralis and on their feeding behaviour. The experiments further considered the importance of previous feeding experience on the responses of the larvae. It was confirmed that herbivore-induced VOCs emitted by maize plants are attractive to the larvae, but exposure to the volatiles decreased the growth rate of caterpillars at early developmental stages. Larvae that had fed on maize previously were more attracted by VOCs of induced maize than larvae that had fed on artificial diet. At relatively high concentrations synthetic green leaf volatiles, indicative of fresh damage, also negatively affected the growth rate of caterpillars, but not at low concentrations. In all cases, feeding by the later stages of the larvae was not affected by the VOCs. The results are discussed in the context of larval foraging behaviour under natural conditions, where there may be a trade-off between using available host plant signals and avoiding competitors and natural enemies.

  8. Regulation of Arabidopsis defense responses against Spodoptera littoralis by CPK-mediated calcium signaling

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    Ishihama Nobuaki

    2010-05-01

    Full Text Available Abstract Background Plant Ca2+ signals are involved in a wide array of intracellular signaling pathways after pest invasion. Ca2+-binding sensory proteins such as Ca2+-dependent protein kinases (CPKs have been predicted to mediate the signaling following Ca2+ influx after insect herbivory. However, until now this prediction was not testable. Results To investigate the roles CPKs play in a herbivore response-signaling pathway, we screened the characteristics of Arabidopsis CPK mutants damaged by a feeding generalist herbivore, Spodoptera littoralis. Following insect attack, the cpk3 and cpk13 mutants showed lower transcript levels of plant defensin gene PDF1.2 compared to wild-type plants. The CPK cascade was not directly linked to the herbivory-induced signaling pathways that were mediated by defense-related phytohormones such as jasmonic acid and ethylene. CPK3 was also suggested to be involved in a negative feedback regulation of the cytosolic Ca2+ levels after herbivory and wounding damage. In vitro kinase assays of CPK3 protein with a suite of substrates demonstrated that the protein phosphorylates transcription factors (including ERF1, HsfB2a and CZF1/ZFAR1 in the presence of Ca2+. CPK13 strongly phosphorylated only HsfB2a, irrespective of the presence of Ca2+. Furthermore, in vivo agroinfiltration assays showed that CPK3-or CPK13-derived phosphorylation of a heat shock factor (HsfB2a promotes PDF1.2 transcriptional activation in the defense response. Conclusions These results reveal the involvement of two Arabidopsis CPKs (CPK3 and CPK13 in the herbivory-induced signaling network via HsfB2a-mediated regulation of the defense-related transcriptional machinery. This cascade is not involved in the phytohormone-related signaling pathways, but rather directly impacts transcription factors for defense responses.

  9. MicroRNAome of Spodoptera frugiperda cells (Sf9) and its alteration following baculovirus infection.

    Science.gov (United States)

    Mehrabadi, Mohammad; Hussain, Mazhar; Asgari, Sassan

    2013-06-01

    MicroRNAs (miRNAs) as small non-coding RNAs play important roles in many biological processes such as development, cell signalling and immune response. Studies also suggest that miRNAs are important in host-virus interactions where the host limits virus infection by differentially expressing miRNAs that target essential viral genes. Here, we identified conserved and new miRNAs from Spodoptera frugiperda cells (Sf9) using a combination of deep sequencing and bioinformatics as well as experimental approaches. S. frugiperda miRNAs share common features of miRNAs in other organisms, such as uracil (U) at the 5' end of miRNA. The 5' ends of the miRNAs were more conserved than the 3' ends, revealing evolutionary protection of the seed region in miRNAs. The predominant miRNAs were found to be conserved among arthropods. The majority of homologous miRNAs were found in Bombyx mori, with 76 of the 90 identified miRNAs. We found that seed shifting and arm switching have happened in this insect's miRNAs. Expression levels of the majority of miRNAs changed following baculovirus infection. Results revealed that baculovirus infection mainly led to an overall suppression of cellular miRNAs. We found four different genes being regulated by sfr-miR-184 at the post-transcriptional level. The data presented here further support conservation of miRNAs in insects and other organisms. In addition, the results reveal a differential expression of host miRNAs upon baculovirus infection, suggesting their potential roles in host-virus interactions. Seed shifting and arm switching happened during evolution of miRNAs in different insects and caused miRNA diversification, which led to changes in the target repository of miRNAs.

  10. A role for Innexin2 and Innexin3 proteins from Spodoptera litura in apoptosis.

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    Tian Liu

    Full Text Available Gap junctions formed by two hemichannels from two neighboring cells are cell-to-cell communication channels; hemichannels are communication channels between intracellular and extracellular environments. Hemichannels are hexameric proteins formed by connexins, pannexins, innexins and vinnexins. Innexin-hemichannels (innexons exist in the lepidopteran cell surface, but their component innexins and functions have not been reported. Recent studies by others have demonstrated that hemichannels, connexons and pannexons from vertebrates serve as regulators of apoptosis via inactivating the PI3K/Akt signaling pathway. Here, the apoptogenic properties of innexons are demonstrated using two innexin cDNAs, Spli-inx2 and Spli-inx3, which were isolated from hemocytes of lepidopteran Spodoptera litura. Alignment analysis revealed that these two genes belong to a conserved innexin family, as they contain the insect signature YYQWV motif at the beginning of the second transmembrane domain. Immunofluorescence showed that two fusion proteins, Inx2-V5 and Inx3-V5, were localized predominantly in the cell membrane, cytoplasm and also nuclei. Ectopic expression in Sf9 cells and over-expression of Inx2 and Inx3 in Spli221 cells promoted apoptosis. In the Spli221 cells, apoptotic cells presented remarkable membrane blebbing. This study also showed that Sf9 and Spli221 cells undergo low level apoptosis under normal culture conditions, but not Hi5 cells. In Hi5 stable cell lines, biotinylation was used to isolate surface proteins and confirm Inx2 and Inx3 localization in the cell membrane and also further data showed that Hi5 cells may activate the PI3K signaling pathway via phosphorylating molecular Akt downstream. This result suggests that innexon-promoted apoptosis may be involving the PI3K/Akt signaling pathway. These findings will facilitate further examinations of the apoptotic regulation by the PI3K/Akt signaling pathway and comparative studies of innexons

  11. Metatranscriptomic Analysis of Larval Guts from Field-Collected and Laboratory-Reared Spodoptera frugiperda from the South American Subtropical Region

    OpenAIRE

    Christina B McCarthy; Cabrera, Natalia A.; Virla, Eduardo G.

    2015-01-01

    This is the first study to report a high-throughput approach integrating gene expression data from Spodoptera frugiperda guts and their associated metatranscriptomes. Our datasets provide information on the potential effects of environmental conditions on the expression profile of S. frugiperda larval guts, their associated metatranscriptome, and putative interactions between them.

  12. Metatranscriptomic Analysis of Larval Guts from Field-Collected and Laboratory-Reared Spodoptera frugiperda from the South American Subtropical Region.

    Science.gov (United States)

    McCarthy, Christina B; Cabrera, Natalia A; Virla, Eduardo G

    2015-07-16

    This is the first study to report a high-throughput approach integrating gene expression data from Spodoptera frugiperda guts and their associated metatranscriptomes. Our datasets provide information on the potential effects of environmental conditions on the expression profile of S. frugiperda larval guts, their associated metatranscriptome, and putative interactions between them.

  13. Effect of baculovirus infection on the mRNA and protein levels of the Spodoptera frugiperda eukaryotic initiation factor 4E

    NARCIS (Netherlands)

    Oers, van M.M.; Veken, van der L.T.J.N.; Vlak, J.M.; Thomas, A.A.M.

    2001-01-01

    The cDNA sequence of eukaryotic translation initiation factor eIF4E was derived from a Spodoptera frugiperda cDNA library. Eight tryptophan residues, typical for eIF4E, are strictly conserved in the encoded 210 amino acid protein. A polyclonal antiserum detected a 26 kDa protein in lepidopteran cell

  14. A novel cytochrome P450 CYP6AB14 gene in Spodoptera litura (Lepidoptera: Noctuidae) and its potential role in plant allelochemical detoxification

    Science.gov (United States)

    Cytochrome P450 monooxygenases (P450) play a prominent role in the adaptation of insects to host plant chemical defenses. To investigate the potential role of P450s in adaptation of the lepidopteran pest Spodoptera litura to host plant allelochemicals, an expressed sequence data set derived from 6th...

  15. A synthetic cryIC gene, encoding a Bacillus thuringiensis δ-endotoxin, confers Spodoptera resistance in alfalfa and tobacco

    NARCIS (Netherlands)

    Strizhov, N.; Keller, M.; Mathur, J.; Koncz-Kaiman, Z.; Bosch, D.; Prudovksy, E.; Schell, J.; Sneh, B.; Koncz, C.; Zilberstein, A.

    1996-01-01

    Spodoptera species, representing widespread polyphagous insect pests, are resistant to Bacillus thuringiensis δ-endotoxins used thus far as insecticides in transgenic plants. Here we describe the chemical synthesis of a cryIC gene by a novel template directed ligation–PCR method. This simple and eco

  16. [Oviposition, development, and reproduction of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) fed on different hosts of economic importance].

    Science.gov (United States)

    Barros, Eduardo M; Torres, Jorge B; Bueno, Adeney F

    2010-01-01

    The host selection for oviposition by Spodoptera frugiperda (J.E. Smith) among corn, millet, cotton and soybean, and its relationship with the biological characteristics were investigated. Free and non-choice tests for oviposition using plots containing five plants each, from each host in plastic greenhouse, resulted in similar oviposition preference among the host plants. In addition, selected biological characteristics of S. frugiperda were determined in the laboratory with larvae feeding on host leaves, and the combination of leaf and cotton boll. Neonate larvae exhibited low success of colonization on cotton boll compared to the leaves of all other hosts. Spodoptera frugiperda fed only on cotton bolls exhibited longer larval and pupal development, and longer adult life span; however with similar egg production. Larvae fed cotton leaves during six days and then transferred to cotton bolls, however, exhibited development and reproduction similar to those reared on corn or only on cotton leaves. Therefore, the variations on immature stages of S. frugiperda were not related with host selection for oviposition which was similar among the studied hosts. Based on our data, the millet as a winter, rotational, and cover crop is a potential host for S. frugiperda, while leaves and cotton bolls were diets of intermediate suitability as compared to corn and soybean leaves.

  17. Interaction of Bacillus thuringiensis vegetative insecticidal protein with ribosomal S2 protein triggers larvicidal activity in Spodoptera frugiperda.

    Science.gov (United States)

    Singh, Gatikrushna; Sachdev, Bindiya; Sharma, Nathilal; Seth, Rakesh; Bhatnagar, Raj K

    2010-11-01

    Vegetative insecticidal protein (Vip3A) is synthesized as an extracellular insecticidal toxin by certain strains of Bacillus thuringiensis. Vip3A is active against several lepidopteran pests of crops. Polyphagous pest, Spodoptera frugiperda, and its cell line Sf21 are sensitive for lyses to Vip3A. Screening of cDNA library prepared from Sf21 cells through yeast two-hybrid system with Vip3A as bait identified ribosomal protein S2 as a toxicity-mediating interacting partner protein. The Vip3A-ribosomal-S2 protein interaction was validated by in vitro pulldown assays and by RNA interference-induced knockdown experiments. Knockdown of expression of S2 protein in Sf21 cells resulted in reduced toxicity of the Vip3A protein. These observations were further extended to adult fifth-instar larvae of Spodoptera litura. Knockdown of S2 expression by injecting corresponding double-stranded RNA resulted in reduced mortality of larvae to Vip3A toxin. Intracellular visualization of S2 protein and Vip3A through confocal microscopy revealed their interaction and localization in cytoplasm and surface of Sf21 cells.

  18. Histopathological effects and determination of the putative receptor of Bacillus thuringiensis Cry1Da toxin in Spodoptera littoralis midgut.

    Science.gov (United States)

    BenFarhat-Touzri, Dalel; Saadaoui, Marwa; Abdelkefi-Mesrati, Lobna; Saadaoui, Imen; Azzouz, Hichem; Tounsi, Slim

    2013-02-01

    Bacillus thuringiensis subsp. aizawai strain HD133, known by its effectiveness against Spodoptera species, produces many insecticidal proteins including Cry1Ab, Cry1Ca and Cry1Da. In the present study, the insecticidal activity of Cry1Da against Spodoptera littoralis was investigated. It showed toxicity with an LC(50) of 224.4 ng/cm(2) with 95% confidence limits of (178.61-270.19) and an LC(90) of 467.77 ng/cm(2) with 95% confidence limits of (392.89-542.65). The midgut histopathology of Cry1Da fed larvae showed vesicle formation in the apical region, vacuolization and destruction of epithelial cells. Biotinylated-activated Cry1Da toxin bound protein of about 65 kDa on blots of S. littoralis brush border membrane preparations. This putative receptor differs in molecular size from those recognized by Cry1C and Vip3A which are active against this polyphagous insect. This difference in midgut receptors strongly supports the use of Cry1Da as insecticidal agent, particularly in case of Cry and/or Vip-resistance management.

  19. Histological study of SlNPV infection on body weight and peritrophic membrane damage of Spodoptera litura larvae

    Directory of Open Access Journals (Sweden)

    NANIN DIAH KURNIAWATI

    2010-11-01

    Full Text Available Sanjaya, Machmudin D, Kurniawati ND. 2010. Histological study of SlNPV infection on body weight and peritrophic membrane damage of Spodoptera litura larvae. Nusantara Bioscience 2: 135-140. The effect of SlNPV infection on body weight and peritrophic membrane damage of Spodoptera litura Fab. larvae has been carried out. The method was used Probit analysis, and based on LD 50 the virus was infected to know body weight and post infection damage.The damage of histological structure caused by SlNPV (0, 315, 390, 465, 540 dan 615 PIB/mL was investigated after 0, 12, 24, 72 and 96 hours post infection. The histological material was prepared by using parafin method after fixation with Bouin Solution, then slice into 7 um and colored with Hematoxilin-Eosin. The result showed that the exposure SlNPV cause decreasing food consumption especially on 540 PIB/mL give average rate as amount of 0.1675 mg. The descriptive obsevation on structural intact of peritrophic membrane histology caused by SlNPV infection shows a tendency to decrease, while in control, there was no damage at all. The longer the exposition of virion in the midgut lumen the more damage on peritrophic membrane occurred. The severest damage occurred 96 hour after infection. The result prove that haNPV virion can destroy hystological structure of midgut.

  20. Haplotype profile comparisons between Spodoptera frugiperda (Lepidoptera:Noctuidae) populations from Mexico with those from Puerto Rico, South America, and the United States and their implications for migratory behavior

    Science.gov (United States)

    Fall armyworm is a major economic pest throughout the Western Hemisphere of maize, cotton, sorghum, and a variety of agricultural grasses and vegetable crops. Previous studies demonstrated extensive annual migrations occurring as far north as Canada from overwintering locations in southern Florida a...

  1. SfDredd, a Novel Initiator Caspase Possessing Activity on Effector Caspase Substrates in Spodoptera frugiperda.

    Science.gov (United States)

    Yang, Zhouning; Zhou, Ke; Liu, Hao; Wu, Andong; Mei, Long; Liu, Qingzhen

    2016-01-01

    Sf9, a cell line derived from Spodoptera frugiperda, is an ideal model organism for studying insect apoptosis. The first notable study that attempted to identify the apoptotic pathway in Sf9 was performed in 1997 and included the discovery of Sf-caspase-1, an effector caspase of Sf9. However, it was not until 2013 that the first initiator caspase in Sf9, SfDronc, was discovered, and the apoptotic pathway in Sf9 became clearer. In this study, we report another caspase of Sf9, SfDredd. SfDredd is highly similar to insect initiator caspase Dredd homologs. Experimentally, recombinant SfDredd underwent autocleavage and exhibited different efficiencies in cleavage of synthetic caspase substrates. This was attributed to its caspase activity for the predicted active site mutation blocked the above autocleavage and synthetic caspase substrates cleavage activity. SfDredd was capable of not only cleaving Sf-caspase-1 in vitro but also cleaving Sf-caspase-1 and inducing apoptosis when it was co-expressed with Sf-caspase-1 in Sf9 cells. The protein level of SfDredd was increased when Sf9 cells were treated by Actinomycin D, whereas silencing of SfDredd reduced apoptosis and Sf-caspase-1 cleavage induced by Actinomycin D treatment. These results clearly indicate that SfDredd functioned as an apoptotic initiator caspase. Apoptosis induced in Sf9 cells by overexpression of SfDredd alone was not as obvious as that induced by SfDronc alone, and the cleavage sites of Sf-caspase-1 for SfDredd and SfDronc are different. In addition, despite sharing a sequence homology with initiator caspases and possessing weak activity on initiator caspase substrates, SfDredd showed strong activity on effector caspase substrates, making it the only insect caspase reported so far functioning similar to human caspase-2 in this aspect. We believe that the discovery of SfDredd, and its different properties from SfDronc, will improve the understanding of apoptosis pathway in Sf9 cells.

  2. Nanotoxicological Effects of SiO2 Nanoparticles on Spodoptera frugiperda Sf9 Cells.

    Science.gov (United States)

    Santo-Orihuela, Pablo L; Foglia, Maria L; Targovnik, Alexandra M; Miranda, Maria V; Desimone, Martin F

    2016-01-01

    The application of silica nanoparticles (NPs) in the biomedical field experienced a great development. The driving forces for these and future developments are the possibility to design NPs with homogeneous size and structure amenable to specific grafting. Moreover, it is possible to tune the characteristics of the NPs to meet the requirements of each specific cell and desired application. Herein, we analyzed the effect of silica NPs of various sizes and surface charge on the viability of Spodoptera frugiperda cells (Sf9 cell line) with the aim of extending the knowledge of possible toxicity of the NPs in the environment and development of new tools for insect control. Moreover, these results will also contribute to develop more effective systems for gene vectors delivery and recombinant proteins expression. Bare silica NPs of 14 nm, 380 nm and 1430 nm as well as amine-modified silica NPs of 131 nm and 448 nm were obtained by the Stöber method. The NPs were characterized by DLS and zeta potential measurements. The cell viability was assessed by the MTT test. It was observed that the 14 nm NPs possess the highest toxic effect. Indeed, after 24 h, the viability of the cells exposed to the lower concentration of NPs (0.12 mg/ml) was about 40% of the value obtained for the control cells not exposed to NPs. Moreover, the exposure to other negative charged NPs also causes a lower activity when compared with the control. Alternatively, lower concentrations of positive charged NPs (i.e.: 0.12 or 0.6 mg/ml) demonstrated to stimulate the proliferation of the cells and higher concentrations (i.e.: 7.2 mg/ml) did not present significant differences with the control. In conclusion, we have demonstrated that the NPs possess an effect that is highly influenced by the size, charge and concentration. Although, silica NPs are being used in the biomedical field, these results contribute to further understanding the risk that could be associated to nanoparticles and how these can be

  3. SfDredd, a Novel Initiator Caspase Possessing Activity on Effector Caspase Substrates in Spodoptera frugiperda.

    Directory of Open Access Journals (Sweden)

    Zhouning Yang

    Full Text Available Sf9, a cell line derived from Spodoptera frugiperda, is an ideal model organism for studying insect apoptosis. The first notable study that attempted to identify the apoptotic pathway in Sf9 was performed in 1997 and included the discovery of Sf-caspase-1, an effector caspase of Sf9. However, it was not until 2013 that the first initiator caspase in Sf9, SfDronc, was discovered, and the apoptotic pathway in Sf9 became clearer. In this study, we report another caspase of Sf9, SfDredd. SfDredd is highly similar to insect initiator caspase Dredd homologs. Experimentally, recombinant SfDredd underwent autocleavage and exhibited different efficiencies in cleavage of synthetic caspase substrates. This was attributed to its caspase activity for the predicted active site mutation blocked the above autocleavage and synthetic caspase substrates cleavage activity. SfDredd was capable of not only cleaving Sf-caspase-1 in vitro but also cleaving Sf-caspase-1 and inducing apoptosis when it was co-expressed with Sf-caspase-1 in Sf9 cells. The protein level of SfDredd was increased when Sf9 cells were treated by Actinomycin D, whereas silencing of SfDredd reduced apoptosis and Sf-caspase-1 cleavage induced by Actinomycin D treatment. These results clearly indicate that SfDredd functioned as an apoptotic initiator caspase. Apoptosis induced in Sf9 cells by overexpression of SfDredd alone was not as obvious as that induced by SfDronc alone, and the cleavage sites of Sf-caspase-1 for SfDredd and SfDronc are different. In addition, despite sharing a sequence homology with initiator caspases and possessing weak activity on initiator caspase substrates, SfDredd showed strong activity on effector caspase substrates, making it the only insect caspase reported so far functioning similar to human caspase-2 in this aspect. We believe that the discovery of SfDredd, and its different properties from SfDronc, will improve the understanding of apoptosis pathway in Sf9 cells.

  4. 澳大利亚粘虫Mythinma convecta的雌性信息素%SEX PHEROMONE COMPONENTS OF FEMALE AUS TRALIAN COMMON ARMYWORM, MYTHIMNA CONV ECTA

    Institute of Scientific and Technical Information of China (English)

    Alice P. Del Socorro; Peter C. Gregg

    2001-01-01

    The sex pheromone components of female common armyworm, Mythimna convecta were collected by means of pheromone gland washing and trapping volatiles from calling females. Z-11-hexadecenal, Z-11-hexadecen1-ol, n-hexadecanal and Z-9-hexadecenal were detected in both the gland and volatile samples. Z-11-hexadecenal was the major component. The behaviour of conspecific males to two synthetic blends of the female sex pheromone was studied in a wind tunnel. Male response to the female sex pheromone was characterised by a behavioural sequence consisting of take off, upwind flight, approach, landing and extrusion of claspers with copulatory attempt. A fourcomponent blend elicited high levels of approach, landing and clasper extrusion from male moths.%用腺体漂洗法和空气吸附法收集了澳大利亚粘虫Mythimna convecta的雌性信息素.在性腺和雌蛾释放物中都检测到了Z11-十六碳烯醛(Z11-Hexadecenal)、Z11-十六碳烯-1-醇(Z11-Hexadecen-1-o1)、n-十六碳醛(n-Hexadecanal)和Z9-十六碳烯醛(Z9-Hexadecenal).在风洞中测定了雄蛾对合成的雌性信息素的混合物的行为反应.雄蛾在风洞中对雌性信息素的行为反应特征包括:起飞、逆风飞行、定向、降落及伸出抱握器企图交尾.研究结果表明,一种四元组份的混合物能引起雄蛾产生较强的行为反应,包括定向、降落、伸出抱握器企图交尾等动作.

  5. Bioassay of Spodoptera exigua Nuclear Polydedrosis Virus and Effect of Different Larvae Density on SeNPV Yield%甜菜夜蛾核型多角体病毒的致病力测定与群养对病毒产量的影响

    Institute of Scientific and Technical Information of China (English)

    徐树兰; 李辉; 陈其津

    2010-01-01

    以3龄中甜菜夜蛾幼虫为试虫,测定出甜菜夜蛾核型多角体病毒的半致死浓度(LC50)为1.66x105 PIB/mL,计算出1×108HB/mL、1×107 PIB/mL、1×106HB/mL 3种浓度的半致死时间(LT50)分别为3.95 d,4.47 d,5.35 d;研究了甜菜夜蛾群养条件对病毒产量的影响,确定出感染浓度为1×108 PIB/mL、感染龄期为5龄初幼虫、饲养密度为30头/dm2时获得的病毒产量最高.

  6. Screening of Bacillus thuringiensis Strains with High Toxicity against Spodoptera exigua and Identification of a New cry2Ah5 Gene%对甜菜夜蛾高杀虫毒力苏云金杆菌菌株的筛选及cry2Ah5的克隆表达

    Institute of Scientific and Technical Information of China (English)

    张雅昆; 赵丹; 郭巍; 王伟; 陆秀君; 李瑞军

    2016-01-01

    利用生物活性测定方法从本实验室已分离保存的Bt菌株中筛选出了5株对甜菜夜蛾具有较高杀虫毒力的菌株.该5株Bt菌株对甜菜夜蛾初孵幼虫的LC50值为0.556 ~ 0.914 mg/mL胞晶混合物,其中GS3菌株杀虫活性最高,LC50值为0.556 mg/mL胞晶混合物;包含晶体形态主要是球形、大菱形、小菱形等;所含基因类型主要是cry1Aa、cry1Ab、cry La、cry1Ia、cry1Ib、cry2Ab、cry2Ad、cry2Ah、cry7Ab、cry9Ba等;5株菌株均表达约60 kD和130~150 kD蛋白,其中2株还表达较弱的80 kD蛋白.从GS3菌株中克隆得到一种新的cry2A基因,GenBank登录号为KT692984,由Bt基因国际命名委员会命名为cry2Ah5.该基因开放阅读框为1899 bp,编码632个氨基酸,编码蛋白分子量为70.8 kD,等电点pI为8.18,与其他Cry2Ah蛋白序列相似性为97%~99%.该基因在大肠杆菌BL21(DE3)中表达约70 kD蛋白,与预测分子量相符.本研究筛选得到5株对甜菜夜蛾具有较高杀虫毒力的Bt菌株,克隆表达了一种新的cry2A基因cry2Ah5,为甜菜夜蛾的生物防治提供了新的菌株及基因资源.

  7. Physiological characters and 16S rDNA sequence phylogenetic analysis of a pathogenic bacterium isolated from Spodoptera exigua Hünber%罹病甜菜夜蛾分离菌株的生理特征及16S rDNA系统发育分析

    Institute of Scientific and Technical Information of China (English)

    齐放军; 刘缨; 季志英

    2004-01-01

    从自然罹病死亡的甜菜夜蛾虫体中分离出甜菜夜蛾致病菌QL-1,对其30项生理特征分析结果表明,QL-1菌株与肠杆菌科(Enterobacteriaceae),沙雷氏菌属(Serratta)中的粘质沙雷氏菌(Serratia marcescens)的生理特征相符合.进一步用PCR扩增出QL-1的16S rDNA基因片段,测定其序列并进行系统发育分析,结果也表明,该菌株与Serratia marcescens处于同一进化树分支中,相似性达99.2%以上.

  8. EFECTO ANTIALIMENTARIO DE LOS EXTRACTOS DE SUSPENSIONES CELULARES DE Azadirachta indica SOBRE Spodoptera frugiperda J. E. Smith EN CONDICIONES DE LABORATORIO ANTIFEEDANT EFFECT OF CELL SUSPENSION EXTRACTS OF Azadirachta indica ON Spodoptera frugiperda J. E. Smith UNDER LABORATORY CONDITIONS

    Directory of Open Access Journals (Sweden)

    Jacqueline Capataz Tafur

    2007-06-01

    Full Text Available Los extractos de neem (Azadirachta indica y sus ingredientes activos como la azadiractina, presentan acción antialimentaria e inhibición del desarrollo de muchos insectos. El objetivo de este estudio fue examinar el efecto antialimentario de los extractos de suspensiones celulares de neem elicitadas a diferentes condiciones de luz y temperatura. Los extractos fueron aplicados en discos de hojas de maíz y sometidas a bioensayos en larvas de segundo instar de Spodoptera frugiperda J. E. Smith (Lepidptera: Noctuidae. Los extractos intracelulares y del medio de cultivo de las suspensiones celulares de A. indica mostraron efecto biológico sobre larvas de S. frugiperda L2, con valores del 100 % de índice antialimentario para los extractos intracelulares de suspensiones de A. indica elicitadas a 15 °C y oscuridad, y del 39,3% para extractos extracelulares (medio de cultivo de suspensiones elicitadas a 35 °C y oscuridad.Extracts of neem (Azadirachta indica and their active ingredients as azadirachtin, present an action and inhibition of the development of many insects. In this study, the antifeedant effect of cell suspension extracts elicited to different conditions of light and temperature was examined. The extracts were applied in corn leaves disks and submitted to bioassays in larvae of second instar of Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae. The intracellular extracts and the culture media (supernatant of the cell suspensions of A. indica showed a biological effect on larvae of S. frugiperda L2, with values of the 100 % of antifeeding index for the intracellular extracts of cells elicited to 15 °C and darkness, and 39,3% of antifeeding index for extracellular extracts (medium of cultivation of elicited suspensions to 35°C , and darkness.

  9. EVALUACIÓN DE ISOESPINTANOL AISLADO DE Oxandra cf. xylopioides (ANNONACEAE SOBRE Spodoptera frugiperda J.E. SMITH (LEPIDOPTERA: NOCTUIDAE EVALUATION OF ISOESPINTANOL ISOLATED FROM Oxandra cf. xylopioides (ANNONACEAE ON Spodoptera frugiperda J.E. SMITH (LEPIDOPTERA: NOCTUIDAE

    Directory of Open Access Journals (Sweden)

    Benjamín Alberto Rojano

    2007-06-01

    Full Text Available Se evaluó el efecto biocida del isoespintanol extraído de Oxandra cf. xylopioides sobre el gusano cogollero del maíz, Spodoptera frugiperda. El isoespintanol fue usado a concentraciones de 100 300 900 y 2700 ppm y aplicado por inmersión de hojas de maíz evaluando sobre larvas del segundo instar. Se determinó el porcentaje de mortalidad a las 24, 48 y 72 horas y se calculó la DL50 y DL90; el análisis de mortalidad demostró que el isoespintanol tiene un efecto tóxico, siendo la dosis de 2700 ppm la que presenta mayor mortalidad. Se determinó una DL50 de 147,07 ppm y una DL90 de 1394 ppm a las 48 horas postratamiento. Estos resultados permitirán avanzar en el estudio y aplicación de insecticidas biológicos para el manejo integrado de plagas.The biocide effect of isoespintanol extracted from Oxandra cf xylopioides was evaluated on the corn earworm Spodoptera frugiperda. Isoespintanol at concentrations of 100 300 900 and 2700 ppm was applied by foliar immersion of maize leaves and it was evaluated on larvae of the second instar. Percentage of mortality at 24, 48 and 72 hours was determined and calculated its DL50 and DL90; the mortality analysis demonstrated that compound has toxic effects, being the dose 2700 ppm the one that presented great mortality. A dose DL50 of 147.07 ppm and a DL90 of 1394 ppm to the 48 hours postreatment was determined. These results will allow to advance in the study and application of biological insecticides directed to the integrated handling of plagues.

  10. COMPARATIVE BIOLOGICAL DATA OF Spodoptera frugiperda (J. E. SMITH, 1797 (LEPDOTERA: NOCTUIDAE IN COTTON AND MAIZE DADOS BIOLÓGICOS COMPARATIVOS DE Spodoptera frugiperda (L. E. Smith, 1797 (LEPIDOPTERA, NOCTUIDAE EM ALGODOEIRO E MILHO

    Directory of Open Access Journals (Sweden)

    José Roberto P. Parra

    2007-09-01

    Full Text Available

    This research deals with the compared biology of Spodoptera frugiperda (J.E. Smnith, 1797 on a natural diet consisting of leaves of the cotton plant (cultivar ";IAC-17"; and leaves of a hybrid corn plant (";HMD-7974";. The experiment was carried out under the following conditions: temperature, 25 +/- 2°C, moisture, 60 +/- 10% R.H. light, a 14-hour photoperiod. The following biological parameters were observed: egg stage: incubation period and viability; larval stage duration, number of instars, weight and viability; pupal stage: duration, weight and viability; adult stage: preoviposition period, fecundity and longevity. Generally speaking within these parameters, the results differed statistically, showing that the insects prefer the leaves of the corn plant.

    Estudou-se a biologia comparada de Spodoptera frugiperda (J.E. Smith, 1797 em dietas naturais (folhas de algodoeiro do cultivar "IAC-17" e folhas de milho provenientes do híbrido "HMD-7974". O ensaio foi conduzido à temperatura de 25 +/- 2°C, U.R. de 60 +/- 10% e fotoperíodo de 14 horas. Foram determinados em cada substrato: número e duração dos instares larvais, duração, peso e viabilidade larval, duração, peso e viabilidade pupal , período de pré-oviposição, fecundidade e longevidade dos adultos e período de incubação e viabilidade dos ovos. De modo geral, os resultados observados para esses parâmetros, diferiram estatisticamente, indicando a preferência das lagartas pelas folhas de milho.

  11. Spodoptera frugiperda (J.E. Smith) with field-evolved resistance to Bt maize are susceptible to Bt pesticides.

    Science.gov (United States)

    Jakka, S R K; Knight, V R; Jurat-Fuentes, J L

    2014-10-01

    Field-evolved resistance to maize event TC1507 expressing the Cry1Fa toxin from Bacillus thuringiensis (Bt) was detected in populations of Spodoptera frugiperda from Puerto Rico. We tested for cross-resistance to purified Cry1A toxins and commercial Bt pesticides in susceptible (Benzon) and TC1507-resistant (456) strains of S. frugiperda. Larvae from the 456 strain exhibited cross-resistance to Cry1Ab and Cry1Ac toxins, while no differences in susceptibility to XenTari WG and DiPel ES pesticides were detected. These data support cross-resistance to toxins that share binding sites with Cry1Fa and no cross-resistance to Bt pesticides in S. frugiperda with field-evolved resistance to Bt maize.

  12. Bioefficacy of Calendula officinalis Linn. (Asteraceae extracts in the control of Spodoptera litura Fabricus (Noctuidae: Lepidoptera under laboratory conditions.

    Directory of Open Access Journals (Sweden)

    Doddamane Manjulakumari

    2012-08-01

    Full Text Available The effect of Calendula officinalis L on the nutritional physiological parameters of Spodoptera litura Fab larvae were studied by treating with leaf and flower extracts in various solvents. Protease and amylase enzyme activities along with their respective substrates were assayed in hemolymph and midgut of treated and untreated larvae. Irrespective of tissues, all the extracts showed significant reduction in the biochemical profile compared to controls. The most significant change was observed in chloroform and petroleum ether leaf and flower extracts treated larvae compared to other extracts suggesting their components affect nutritional physiology of S.litura. Hence, Calendula extracts can not only be used to treat human ailments but also as an effective botanical pesticide.

  13. Bioactivity of extracts and isolated compounds from Vitex polygama (Verbenaceae) and Siphoneugena densiflora (Myrtaceae) against Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Gallo, Margareth B C; Rocha, Waldireny C; da Cunha, Uemerson S; Diogo, Fernanda A; da Silva, Fernando C; Vieira, Paulo C; Vendramim, José D; Fernandes, João B; da Silva, M Fátima das G F; Batista-Pereira, Luciane G

    2006-11-01

    The effects of crude extracts, fractions and isolated compounds from Vitex polygama Cham. and Siphoneugena densiflora Berg were evaluated on the development of Spodoptera frugiperda JE Smith, a destructive insect pest of corn and several other crops. The extracts and fractions were incorporated into an artificial diet at 1 mg g(-1) and offered to the insect during its larval stage. Length and viability of larval and pupal stages as well as pupal weight were assessed. Isolated compounds were tested through superficial contamination of the diet at 0.1 mg g(-1). Weight and viability of ten-day-old larvae were determined. Methanolic and hydroalcoholic S. densiflora extracts caused 100% larval mortality, while leaf and fruit hydroalcoholic extracts from V. polygama were the most active. Among the isolated compounds, flavonoids presented the best insecticidal results, and tannins the best larval growth inhibition.

  14. The Influence of Cadmium on the Food Consumption and Utilization of the Cotton Leaf Worm Spodoptera littoralis (Boisd. (Lepidoptera: Noctuidae

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    Shahenda A. Abu ElEla

    2015-06-01

    Full Text Available The third, fourth, fifth, and sixth instars of the cotton leaf worm Spodoptera littoralis (Boisduval, 1833 were reared on castor bean leaves Ricinus communis (Linnaeus, 1753 treated with cadmium 100 mg CdCl2/kg, using the dipping method, to evaluate the effect of cadmium (Cd on nutritional indices. It was observed that the consumption index was significantly decreased at all the studied instars except for the third instar. The absorptive capacity, in terms of approximate digestibility, was significantly decreased at the sixth instar. The food utilization efficiencies, in terms of the conversion of ingested and digested food (ECD to biomass, were significantly decreased at both fourth and fifth instars. Moreover, the ECD was significantly decreased at the sixth instar. The growth rate decreased at the different studied instars except for the sixth instar.

  15. Effect of Some Environmental Factors on the Toxicity of Azadirachtin to the Egyptian Cotton Leafworm Spodoptera littoralis (Boisduval (Lepidoptera: Noctuidae

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    El-Sayed H. Shaurub

    2014-12-01

    Full Text Available Although the bio-degradation of azadirachtin was well studied under storage or environmental conditions, its toxicity was not characterized so far under the impact of environmental conditions. Therefore, the present study aims to elucidate the toxicity of azadirachtin, at the level of LC50, to the fourth larval instars of Spodoptera littoralis (Boisduval under the stress of temperature, ultraviolet radiation (365 nm (UV-A and of artificial sunlight. The increase in post-treatment temperatures insignificantly affected azadirachtin toxicity. Likewise, insignificant change was also attained for the increase in the exposure periods of both UV and sunlight, except for exposure to sunlight without UV filter starting from 10 h, where the toxicity of azadirachtin was significantly declined. It can be concluded that azadirachtin toxicity will last efficiently against S. littoralis larvae under the stress of the environmental factors prevailing during the season of cotton cultivation in Egypt.

  16. Insecticidal activity of venomous saliva from Rhynocoris fuscipes (Reduviidae against Spodoptera litura and Helicoverpa armigera by microinjection and oral administration

    Directory of Open Access Journals (Sweden)

    K Sahayaraj

    2011-01-01

    Full Text Available Rhynocoris fuscipes is a potential predator of many economically important pests in India. In the present study, its venomous saliva (VS was collected by milking and diluted with HPLC grade water to different concentrations (200, 400, 600, 800 and 1000 ppm. Microinjection of Rhynocoris fuscipes VS was more toxic than its oral administration in Helicoverpa armigera (cotton bollworm and Spodoptera litura (tobacco cutworm. Thus, R. fuscipes VS was found to be toxic to third instar S. litura and H. armigera with respective LD50s of 846.35 and 861.60 ppm/larva at 96 hours after microinjection. The current results showed that VS of Rhynocoris fuscipes caused mortality of H. armigera and S. litura. Active peptides from VS may be isolated, identified and assessed for their impact in order to ascertain how they alter the physiology of these pests, information that could be applicable in pest management programs.

  17. A comparison of the pre-calling period between Japanese and southeastern Asian populations of Spodoptera litura

    Institute of Scientific and Technical Information of China (English)

    MIKA MURATA; HIROYUKI MATSUKI; RYOHEI YAMAOKA; SUMIO TOJO

    2006-01-01

    The pre-calling behavior of female adults of the common cutworm, Spodoptera litura (Lepidoptera: Noctuidae) collected in southern Japan and southeastern Asian countries was investigated. Most females started calling on days 1-4 after adult emergence. In three populations obtained in Saga prefecture in Kyushu mainland, Japan, two different patterns of pre-calling period (PCP) were observed: one was the above-mentioned pattern shown by most individuals, and the other was a pattern in which females sexually matured within several hours after emergence. Diel periodicity was shown in the time of calling activity, and its pattern varied among the populations. Pre-calling period was stable over successive generations in the laboratory.

  18. Bioactivity of Pseudocalymma alliaceum (Lam.) Sandwith (Bignoniaceae) against Spodoptera litura Fabricius and Helicoverpa armigera Hübner (Lepidotera:Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    Alagarmalai Jeyasankar; Tamilarasu Chinnamani

    2014-01-01

    Objective: To evaluate the antifeedant, larvicidal and insect growth inhibitory activities of crude extracts of Pseudocalymma alliaceum tested against fourth instar larvae of Spodoptera litura (S. litura) and Helicoverpa armigera (H. armigera). Methods: Hexane, chloroform and ethyl acetate extracts were prepared and tested for antifeedant, insecticidal and growth inhibitory activities against fourth instar larvae of S. litura and H. armigera.Results:Ethyl acetate extract showed promising antifeedant, insecticidal activity against S. litura and H. armigera. Maximum percentage of deformed larvae, pupae and adults were found on treatment with ethyl acetate extract. Percentage of successful adult emergence was deteriorated by extract treated larvae. Ethyl acetate extracts of Pseudocalymma alliaceum, showed higher percentage of antifeedant, insecticidal and growth inhibition activities.Conclusions:This is the first report on S. litura and H. armigera. Further, the active compounds isolated from the ethyl acetate extracts will be useful for controlling economically important insect pests.

  19. Baculovirus p35 gene is oppositely regulated by P53 and AP-1 like factors in Spodoptera frugiperda

    Energy Technology Data Exchange (ETDEWEB)

    Mohareer, Krishnaveni [Laboratory of Molecular and Cell Biology, Center for DNA Fingerprinting and Diagnostics, Hyderabad 500001 (India); Institute of Life Sciences, University of Hyderabad Campus, Prof. C.R. Rao Road, Gachibowli, Hyderabad 500046 (India); Sahdev, Sudhir [Laboratory of Molecular and Cell Biology, Center for DNA Fingerprinting and Diagnostics, Hyderabad 500001 (India); Ranbaxy Pharmaceuticals, Gurgaon, New Delhi (India); Hasnain, Seyed E., E-mail: seh@bioschool.iitd.ac.in [Institute of Life Sciences, University of Hyderabad Campus, Prof. C.R. Rao Road, Gachibowli, Hyderabad 500046 (India); Kusuma School of Biological Sciences, IIT Delhi, New Delhi 110016 (India); ILBS, Vasant Kunj, New Delhi (India); King Saud University, Riyadh, KSA (Saudi Arabia)

    2011-11-04

    Highlights: Black-Right-Pointing-Pointer Baculovirus p35 is regulated by both viral and host factors. Black-Right-Pointing-Pointer Baculovirus p35 is negatively regulated by SfP53-like factor. Black-Right-Pointing-Pointer Baculovirus p35 is positively regulated by SfAP-1-like factor. -- Abstract: Baculovirus p35 belongs to the early class of genes of AcMNPV and requires viral factors like Immediate Early protein-1 for its transcription. To investigate the role of host factors in regulating p35 gene expression, the putative transcription factor binding sites were examined in silico and the role of these factors in influencing the transcription of p35 gene was assessed. We focused our studies on AP-1 and P53-like factors, which are activated under oxidative stress conditions. The AP-1 motif is located at -1401 while P53 motif is at -1912 relative to p35 translation start site. The predicted AP-1 and P53 elements formed specific complexes with Spodoptera frugiperda nuclear extracts. Both AP-1 and P53 motif binding proteins were down regulated as a function of AcMNPV infection in Spodoptera cells. To address the question whether during an oxidative outburst, the p35 transcription is enhanced; we investigated the role of these oxidative stress induced host transcription factors in influencing p35 gene transcription. Reporter assays revealed that AP-1 element enhances the transcription of p35 by a factor of two. Interestingly, P53 element appears to repress the transcription of p35 gene.

  20. Analyzing blends of herbivore-induced volatile organic compounds with factor analysis: revisiting "cotton plant, Gossypium hirsutum L., defense in response to nitrogen fertilization".

    Science.gov (United States)

    Chen, Yigen

    2013-04-01

    Many herbivorous, predaceous, and parasitic insects use constitutive and herbivore-induced volatile organic compounds (VOCs) to locate their respective host plant, prey, and hosts. Multivariate statistical tools (e.g., factor analysis) are recognized increasingly as an appropriate approach for analyzing intercorrelated data such as presence/absence or quantities of VOCs. One challenge of implementing factor analysis is determining how many new variables (factors) to retain in the final analysis. I demonstrate a method proposed by Johnson and Wichern to mitigate this problem by using VOC data published in Chen et al. The advantage of using loading (or weight) transformation in interpretation of new variables was also illustrated in the example. Factor analysis found similar nitrogen fertilization effects on VOC production as those in Chen et al. Similarities were 1) nitrogen fertilization interacted with herbivore damage status on VOC production: at low nitrogen (42 ppm) level, beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), damage elicited increases in VOC production, whereas at high nitrogen (196 ppm) VOC production was suppressed; 2) nitrogen fertilization did not affect limonene, alpha-pinene, and beta-pinene production. The seven individual VOCs significantly affected by nitrogen fertilization in Chen et al. were (Z)-3-hexenal, (E)-2-hexenal, (E)-beta-farnesene, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), alpha-bergamotene, gamma-bisabolene, and bisabolol, of which only three ((E)-beta-farnesene, gamma-bisabolene, and bisabolol) weighed heavily on factor 1 in the current study.

  1. Nicotine's defensive function in nature.

    Directory of Open Access Journals (Sweden)

    Anke Steppuhn

    2004-08-01

    Full Text Available Plants produce metabolites that directly decrease herbivore performance, and as a consequence, herbivores are selected for resistance to these metabolites. To determine whether these metabolites actually function as defenses requires measuring the performance of plants that are altered only in the production of a certain metabolite. To date, the defensive value of most plant resistance traits has not been demonstrated in nature. We transformed native tobacco(Nicotiana attenuata with a consensus fragment of its two putrescine N-methyl transferase (pmt genes in either antisense or inverted-repeat (IRpmt orientations. Only the latter reduced (by greater than 95% constitutive and inducible nicotine. With D(4-nicotinic acid (NA, we demonstrate that silencing pmt inhibits nicotine production, while the excess NA dimerizes to form anatabine. Larvae of the nicotine-adapted herbivore Manduca sexta (tobacco hornworm grew faster and, like the beetle Diabrotica undecimpunctata, preferred IRpmt plants in choice tests. When planted in their native habitat, IRpmt plants were attacked more frequently and, compared to wild-type plants, lost 3-fold more leaf area from a variety of native herbivores, of which the beet armyworm, Spodoptera exigua, and Trimerotropis spp. grasshoppers caused the most damage. These results provide strong evidence that nicotine functions as an efficient defense in nature and highlights the value of transgenic techniques for ecological research.

  2. Accumulation of 5-hydroxynorvaline in maize (Zea mays) leaves is induced by insect feeding and abiotic stress.

    Science.gov (United States)

    Yan, Jian; Lipka, Alexander E; Schmelz, Eric A; Buckler, Edward S; Jander, Georg

    2015-02-01

    Plants produce a wide variety of defensive metabolites to protect themselves against herbivores and pathogens. Non-protein amino acids, which are present in many plant species, can have a defensive function through their mis-incorporation during protein synthesis and/or inhibition of biosynthetic pathways in primary metabolism. 5-Hydroxynorvaline was identified in a targeted search for previously unknown non-protein amino acids in the leaves of maize (Zea mays) inbred line B73. Accumulation of this compound increases during herbivory by aphids (Rhopalosiphum maidis, corn leaf aphid) and caterpillars (Spodoptera exigua, beet armyworm), as well as in response to treatment with the plant signalling molecules methyl jasmonate, salicylic acid and abscisic acid. In contrast, ethylene signalling reduced 5-hydroxynorvaline abundance. Drought stress induced 5-hydroxynorvaline accumulation to a higher level than insect feeding or treatment with defence signalling molecules. In field-grown plants, the 5-hydroxynorvaline concentration was highest in above-ground vegetative tissue, but it was also detectable in roots and dry seeds. When 5-hydroxynorvaline was added to aphid artificial diet at concentrations similar to those found in maize leaves and stems, R. maidis reproduction was reduced, indicating that this maize metabolite may have a defensive function. Among 27 tested maize inbred lines there was a greater than 10-fold range in the accumulation of foliar 5-hydroxynorvaline. Genetic mapping populations derived from a subset of these inbred lines were used to map quantitative trait loci for 5-hydroxynorvaline accumulation to maize chromosomes 5 and 7.

  3. Avian conservation practices strengthen ecosystem services in California vineyards.

    Science.gov (United States)

    Jedlicka, Julie A; Greenberg, Russell; Letourneau, Deborah K

    2011-01-01

    Insectivorous Western Bluebirds (Sialia mexicana) occupy vineyard nest boxes established by California winegrape growers who want to encourage avian conservation. Experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. We compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without nest boxes. The average species richness of avian insectivores increased by over 50 percent compared to controls. Insectivorous bird density nearly quadrupled, primarily due to a tenfold increase in Western Bluebird abundance. In contrast, there was no significant difference in the abundance of omnivorous or granivorous bird species some of which opportunistically forage on grapes. In a sentinel prey experiment, 2.4 times more live beet armyworms (Spodoptera exigua) were removed in the nest box treatment than in the control. As an estimate of the maximum foraging services provided by insectivorous birds, we found that larval removal rates measured immediately below occupied boxes averaged 3.5 times greater than in the control. Consequently the presence of Western Bluebirds in vineyard nest boxes strengthened ecosystem services to winegrape growers, illustrating a benefit of agroecological conservation practices. Predator addition and sentinel prey experiments lack some disadvantages of predator exclusion experiments and were robust methodologies for detecting ecosystem services.

  4. Avian conservation practices strengthen ecosystem services in California vineyards.

    Directory of Open Access Journals (Sweden)

    Julie A Jedlicka

    Full Text Available Insectivorous Western Bluebirds (Sialia mexicana occupy vineyard nest boxes established by California winegrape growers who want to encourage avian conservation. Experimentally, the provision of available nest sites serves as an alternative to exclosure methods for isolating the potential ecosystem services provided by foraging birds. We compared the abundance and species richness of avian foragers and removal rates of sentinel prey in treatments with songbird nest boxes and controls without nest boxes. The average species richness of avian insectivores increased by over 50 percent compared to controls. Insectivorous bird density nearly quadrupled, primarily due to a tenfold increase in Western Bluebird abundance. In contrast, there was no significant difference in the abundance of omnivorous or granivorous bird species some of which opportunistically forage on grapes. In a sentinel prey experiment, 2.4 times more live beet armyworms (Spodoptera exigua were removed in the nest box treatment than in the control. As an estimate of the maximum foraging services provided by insectivorous birds, we found that larval removal rates measured immediately below occupied boxes averaged 3.5 times greater than in the control. Consequently the presence of Western Bluebirds in vineyard nest boxes strengthened ecosystem services to winegrape growers, illustrating a benefit of agroecological conservation practices. Predator addition and sentinel prey experiments lack some disadvantages of predator exclusion experiments and were robust methodologies for detecting ecosystem services.

  5. Improvement of pest resistance in transgenic tobacco plants expressing dsRNA of an insect-associated gene EcR.

    Directory of Open Access Journals (Sweden)

    Jin-Qi Zhu

    Full Text Available The adoption of pest-resistant transgenic plants to reduce yield loss and pesticide utilization has been successful in the past three decades. Recently, transgenic plant expressing double-stranded RNA (dsRNA targeting pest genes emerges as a promising strategy for improving pest resistance in crops. The steroid hormone, 20-hydroxyecdysone (20E, predominately controls insect molting via its nuclear receptor complex, EcR-USP. Here we report that pest resistance is improved in transgenic tobacco plants expressing dsRNA of EcR from the cotton bollworm, Helicoverpa armigera, a serious lepidopteran pest for a variety of crops. When H. armigera larvae were fed with the whole transgenic tobacco plants expressing EcR dsRNA, resistance to H. armigera was significantly improved in transgenic plants. Meanwhile, when H. armigera larvae were fed with leaves of transgenic tobacco plants expressing EcR dsRNA, its EcR mRNA level was dramatically decreased causing molting defects and larval lethality. In addition, the transgenic tobacco plants expressing H. armigera EcR dsRNA were also resistant to another lepidopteran pest, the beet armyworm, Spodoptera exigua, due to the high similarity in the nucleotide sequences of their EcR genes. This study provides additional evidence that transgenic plant expressing dsRNA targeting insect-associated genes is able to improve pest resistance.

  6. Coleus barbatus Benth and Ocimum basilicum L. (Lamiaceae, New Host Plants to Spodoptera cosmioides (Walker (Lepidoptera: Noctuidae in Sinop, State of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Evaldo Pires

    2014-04-01

    Resumo. Coleus barbatus Benth e Ocimum basilicum L. são espécies de plantas comumente utilizadas com fins medicinais e gastronômicos, respectivamente. Lagartas do gênero Spodoptera são generalistas devido à ampla variedade de plantas que utilizam como recurso alimentar. O objetivo desta pesquisa foi registrar a ocorrência de Spodoptera cosmioides (Walker (Lepidoptera: Noctuidae no município de Sinop, Mato Grosso, Brasil, e ainda, relatar C. barbatus e O. basilicum como potenciais plantas hospedeiras para esta espécie de inseto. Recomenda-se ainda a inclusão de S. cosmioides em monitoramentos visando o Manejo Integrado de Pragas (MIP nestas plantas.

  7. 斜纹夜蛾性信息素的研究与应用%Study and Application of Sex Pheromone in Spodoptera litura

    Institute of Scientific and Technical Information of China (English)

    张显勇; 高惠姗; 江敏华; 赖创荣; 郑常格

    2016-01-01

    介绍了斜纹夜蛾性信息素的组分,阐述了性信息素的感受与调控机制和应用性信息素监测和防治斜纹夜蛾技术,分析了影响性信息素诱捕效果的因素,并展望了斜纹夜蛾性信息素今后的研究方向。%The components of Spodoptera litura sex pheromone were introduced, feelings of sex pheromone, control mechanism, monitoring and control of applied sex pheromone were elaborated, factors affecting the trapping effect were analyzed, the future research direction of Spo-doptera litura sex pheromone was forecasted.

  8. Sublethal Effects of Essential Oils From Eucalyptus staigeriana (Myrtales: Myrtaceae), Ocimum gratissimum (Lamiales: Laminaceae), and Foeniculum vulgare (Apiales: Apiaceae) on the Biology of Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Cruz, G S; Wanderley-Teixeira, V; Oliveira, J V; Lopes, F S C; Barbosa, D R S; Breda, M O; Dutra, K A; Guedes, C A; Navarro, D M A F; Teixeira, A A C

    2016-04-01

    Spodoptera frugiperda (Smith 1797) (Lepidoptera: Noctuidae) is a major pest of maize, Zea mays L. Its control is often achieved through repeated applications per season of insecticides, which may lead to adverse effects on the ecosystem. Thus, the study of alternative methods with less environmental impact has expanded to include the use of essential oils. These oils are products of the secondary metabolism in plants, and their insecticidal activity has been widely demonstrated in populations of many pest insects. This study evaluated the insecticidal activities of essential oils from Eucalyptus staigeriana, Ocimum gratissimum, and Foeniculum vulgare on Spodoptera frugiperda. Gas chromatography–mass spectrometry profiles and contact toxicity of these oils as well as their sublethal effects on larvae and reproductive parameters in adults were evaluated. All three oils had sublethal effects on S. frugiperda; however, the oil of O. gratissimum showed the best results at all doses tested. These essential oils may have promise for control of S. frugiperda.

  9. Atividade inseticida de óleos essenciais de Pelargonium graveolens l'Herit e Lippia alba (Mill N. E. Brown sobre Spodoptera frugiperda (J. E. Smith

    Directory of Open Access Journals (Sweden)

    Edenilson dos S. Niculau

    2013-01-01

    Full Text Available Insecticidal activity of essential oils of Pelargonium graveolens, Lippia alba and compounds geraniol, linalool, 1,8-cineole, limonene, carvone, citral and Azamax® were evaluated against Spodoptera frugiperda. Topical application assay showed essential oil of P. graveolens has acute toxicity against Spodoptera frugiperda larvae (third instar with LD50 1.13 µg/mg per insect and LD90 2.56 µg/mg per insect. Three essential oils of L. alba also exhibited insecticidal activity with LD50 ranging from 1.20 to 1.56 µg/mg per insect and LD90 from 2.60 to 3.75 µg/mg per insect. Geraniol, linalool, carvone and citral caused significant mortality of 30, 90, 84 and 64% respectively, compared to negative control. The bioinsecticide, Azamax®, caused lower mortality than the compounds of the essential oils.

  10. In Vivo and In Vitro Binding of Vip3Aa to Spodoptera frugiperda Midgut and Characterization of Binding Sites by 125I Radiolabeling

    OpenAIRE

    Chakroun, Maissa; Ferré, Juan

    2014-01-01

    Bacillus thuringiensis vegetative insecticidal proteins (Vip3A) have been recently introduced in important crops as a strategy to delay the emerging resistance to the existing Cry toxins. The mode of action of Vip3A proteins has been studied in Spodoptera frugiperda with the aim of characterizing their binding to the insect midgut. Immunofluorescence histological localization of Vip3Aa in the midgut of intoxicated larvae showed that Vip3Aa bound to the brush border membrane along the entire a...

  11. Study of the Bacillus thuringiensis Vip3Aa16 histopathological effects and determination of its putative binding proteins in the midgut of Spodoptera littoralis

    OpenAIRE

    Abdelkefi-Mesrati, Lobna; Boukedi, Hanen; Dammak-Karray, Mariam; Sellami-Boudawara, Tahya; Jaoua, Samir; Tounsi, Slim

    2011-01-01

    The bacterium Bacillus thuringiensis produces, at the vegetative stage of its growth, Vip3A proteins with activity against a broad spectrum of lepidopteran insects. The Egyptian cotton leaf worm (Spodoptera littoralis) is an important agricultural pest that is susceptible to the Vip3Aa16 protein of Bacillus thuringiensis kurstaki strain BUPM95. The midgut histopathology of Vip3Aa fed larvae showed vacuolization of the cytoplasm, brush border membrane destruction, vesicle formation in the apic...

  12. Investigation of the steps involved in the difference of susceptibility of Ephestia kuehniella and Spodoptera littoralis to the Bacillus thuringiensis Vip3Aa16 toxin

    OpenAIRE

    Abdelkefi-Mesrati, L.; Boukedi, H.; Chakroun, M.; Kamoun, F.; Azzouz, H.; Tounsi, S.; Rouis, S.; Jaoua, S.

    2011-01-01

    BUPM95 is a Bacillus thuringiensis subsp. kurstaki strain producing the Vip3Aa16 toxin with an interesting insecticidal activity against the Lepidopteran larvae Ephestia kuehniella. Study of different steps in the mode of action of this Vegetative Insecticidal Protein on the Mediterranean flour moth (E. kuehniella) was carried out in the aim to investigate the origin of the higher susceptibility of this insect to Vip3Aa16 toxin compared to that of the Egyptian cotton leaf worm Spodoptera litt...

  13. Actividad biológica de extractos de Melia azedarach sobre larvas de Spodoptera eridania (Lepidoptera: Noctuidae Biological activity of extracts of Melia azedarach on larvae of Spodoptera eridania (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    María R. Rossetti

    2008-06-01

    Full Text Available En la búsqueda de compuestos botánicos con potencial uso insecticida, se evaluó la actividad de extractos de fruto maduro y hojas senescentes de Melia azedarach L. (2, 5 y 10%, sobre larvas de Spodoptera eridania Cramer (Lepidoptera: Noctuidae especie polífaga considerada plaga esporádica de importantes cultivos. Mediante pruebas de elección, se registró el consumo y se calculó un índice de inhibición alimentaria. En pruebas sin posibilidad de elección se estimó el consumo, la mortalidad, el peso de larvas y excretas, y se calcularon índices nutricionales. Cuando las larvas pudieron optar, se observó un fuerte efecto antialimentario de los extractos. En los ensayos de alimentación obligada, los extractos de fruto y hoja redujeron fuertemente el consumo y peso larval respecto al control, excepto la menor dosis de fruto. Ninguna oruga llegó a pupar al entregarle alimento rociado con extracto de hoja o con extracto de fruto en las dosis más altas. Los índices nutricionales corroboraron la actividad antialimentaria, revelando efectos negativos de los extractos sobre las tasas relativas de consumo y crecimiento, y sobre la eficiencia de utilización del alimento ingerido y digerido, aunque la digestibilidad no fue afectada. Los resultados sugieren que los extractos de M. azedarach podrían ser incorporados en programas de manejo de este insecto plaga.In the course of searching for plant chemicals with potential insecticide properties, the activity of Melia azedarach L. senescent leaf and ripe fruit extracts (2, 5 and 10% was evaluated on larvae of Spodoptera eridania Cramer (Lepidoptera: Noctuidae. This polyphagous species is considered a sporadic pest on many important crops. Food consumption was assessed and an antifeedant index was calculated through choice tests. Also, food consumption, larval mortality, weight and depositions were recorded and nutritional indices were calculated in no-choice tests. Results from choice tests

  14. Ocorrência de Erinnyis ello e Spodoptera marima na cultura da mamona no Rio Grande do Sul Occurrence of Erinnyis ello and Spodoptera marima in castor bean plantation in Rio Grande do Sul State, Brazil

    Directory of Open Access Journals (Sweden)

    Leandro do Prado Ribeiro

    2008-11-01

    Full Text Available O objetivo do trabalho foi realizar o levantamento populacional e verificar a ocorrência de lepidópteros associados à cultura da mamona no Rio Grande do Sul, Brasil. O estudo populacional foi realizado em cultivos de mamona, cultivar "AL Guarany 2002", implantados na área experimental do Departamento de Solos da Universidade Federal de Santa Maria, em Santa Maria, RS. A semeadura ocorreu na primeira quinzena do mês de novembro de 2006, em uma área de 0,3ha, aproximadamente. As avaliações semanais iniciaram aos 20 dias após a emergência das plantas e persistiram até a maturação das bagas, perfazendo um total de 15 avaliações, sendo as lagartas coletadas manualmente em 40 plantas aleatórias/data de avaliação. Os espécimens coletados foram levados ao Laboratório de Entomologia do DFS/UFSM, onde foram mantidos até a fase adulta. Spodoptera marima Schs. (Lepidoptera: Noctuidae e Erinnyis ello L. (Lepidoptera: Sphingidae representaram um percentual de 15,2 e 28,3% do total de lagartas coletadas, respectivamente. Assim, este estudo relata a primeira ocorrência dessas duas espécies de lepidópteros em associação à cultura da mamona no Rio Grande do Sul.The aim of this research was to carry out the population survey and check an occurrence of lepidopterous associated to castor bean plantation in Rio Grande do Sul State, Brazil. The population study was performed in castor bean plantation, AL Guarany 2002 cultivate, implemented in the experimental area Soils Department at Federal University of Santa Maria, in Santa Maria, Rio Grande do Sul State. The sow occurred in the first fifteen days of november of 2006, in an area of around 0,3 ha. The weekly appraisement started 20 days after the emergency of the plants and went until their maturation, creating a total of 15 evaluations, being the caterpillars hand collected in 40 random plants/ date of evaluation. The collected samples were brought to the Laboratory of Entomology at DFS

  15. AVALIAÇÃO DE DANOS Spodoptera frugiperda (J. E. Smith, 1797 (Lepidoptera, Noctuidae NO ALGODOEIRO CULTIVAR IAC-17 EVALUATION OF Spodoptera frugiperda (J. E. SMITH, 1797 (LEPIDOPTERA, NOCTUIDAE DAMAGES IN THE COTTON PLANT IAC-17 CULTIVAR

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    Valquíria da Rocha Santos Veloso

    2007-09-01

    Full Text Available

    Com a finalidade de avaliar os danos causados por Spodoptera frugiperda (J. E. Smith, 1797 na produção do algodoeiro, foi conduzido o presente trabalho. Foram utilizados quatro níveis de infestação artificial aos 75 e 95 dias da germinação das plantas. As avaliações foram feitas através da produção de algodão em caroço, por parcela. As diferenças na produção em plantas infestadas aos 75 e 95 dias da germinação, comparadas com a testemunha, foram estatisticamente significativas para as infestações com 1, 2 e 4 lagartas por planta. Aos 75 dias, devido ao fato de existirem poucos órgãos frutíferos, a redução na produção deu-se devido ao ataque das lagartas aos ponteiros e aos caules, com corte parcial ou total. Na infestação aos 95 dias a produção diminuiu linearmente em relação aos diferentes níveis de infestação; nesta época as lagartas mostraram preferência pelas estruturas frutíferas do algodoeiro.

    This work was conducted with the purpose of evaluate the damages provoked by Spodoptera frugiperda (J. E. Smith, 1797 in cotton-plant yield. To evaluate the decrease in the cotton yield four levels of artificial infestation were used at 75 and 95 days from plant germination. The damage was evaluated on cotton seeds per plot. The differences in the yield of infested plants at 75 and 95 days from germination, when compared to the check, were statistically significant for the infestations of 1, 2 and 4 larvae per plant. At 75 days when the plants presented a low number of fruit organs, the yield decrease was due to the attack of larvae cutting partially or totally the shoots and stems. As to the infestation at 95 days the yield decreased linearly in relation to the different levels of infestation; at this time the larvae showed a preference for the fruit

  16. Avaliação de acessos de milho para resistência a Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae em laboratório Evaluation of a maize collection to Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae resistance in laboratory

    Directory of Open Access Journals (Sweden)

    Francisca Wilma Neide de Lima

    2006-01-01

    Full Text Available Avaliou-se uma coleção de milho para resistência à lagarta de Spodoptera frugiperda (J.E.Smith (Lepidóptera: Noctuidae em testes de laboratório da UFRA. Utilizou-se 25 acessos de milho proveniente do banco de germoplasma da Embrapa Milho e Sorgo, em um experimento inteiramente ao acaso com três repetições. Observou-se diariamente o desenvolvimento dos insetos durante as fases de larva e pupa, para registrar as alterações biológicas promovidas pelos acessos de milho. Os dados observados foram submetidos à ANOVA, as médias foram comparadas pelo teste SNK e através da análise de regressão linear, determinou-se o grau de dependência entre o consumo foliar de S. frugiperda na fase larval e a respectiva biomassa do inseto na fase pupal. Os resultados mostraram que houve influência dos acessos de milho sobre o desenvolvimento da lagarta-do-cartucho do milho. Os acessos que promoveram a menor percentagem de viabilidade de lagartas foram AM 013, RO 009 e MA 002, enquanto RR 168 e PA 110 foram os menos consumidos pelas lagartas de S. frugiperda.A collection of maize was evaluated to corn population resistance to the corn caterpillar Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae in laboratory at UFRA. There were used 25 corn population from the germoplasm bank of Embrapa Maize and Sorghum Research Center with three repetitions. The development of this insect was daily observed, from the caterpillar phase to the pupal, to register the biological differences promoted by maize population. The observed data were submitted to ANOVA, the averages were compared by the SNK test and the linear regression analysis was determined between leaf consumption and the respective pupal biomass. The results showed that the maize population affected the larval development. The least larval viability was observed on populations AM 013, RO 009 and MA 002, and the leaf consumption by S.frugiperda larvae was on RR 168 and PA 110.

  17. 30种吗啉化合物对昆虫细胞Spodoptera frugiperda(Sf9)的毒力筛选%Cytotoxicity of the 30 Morpholinium Compounds against Spodoptera frugiperda (Sf9) Cells

    Institute of Scientific and Technical Information of China (English)

    张新刚; 史冠莹; 可利钦; 陶科; 侯太平

    2012-01-01

    [Aims] The main aim of this study was to measure the toxic effect of 30 morpholinium compounds against Spodoptera frugiperda(Sf9) cells. And the influence of these compounds on cell cycle was also studied. [Methods] MTT and flow cytometry assays were used to measure the cytotoxicity and cell cycle. [Results] The results revealed that 27 compounds had inhibitory effects on Sf9 cells. The inhibition rates of compound A3, A4 and A6 were (69.5±1.54)%, (67.9±1.87)% and (53.6±0.98)% respectively. Formation of apoptotic bodies were observed after treatment with 50 μmol/L compound A3. The normal cell cycle may be interfered by compound A3, and some cells were arrested in S phase. [Conclusions] Compound A3, A4 and A6 exhibited good inhibitory effects against Sf9 cells. After treatment with compound A3, the normal cell cycle was interfered accompanied by apoptosis phenomenon.%[目的]利用Spodoptera frugiperda(Sf9)细胞,测定30种吗啉化合物的毒力,研究化合物对细胞周期的影响.[方法]毒力测定采用MTT法,用流式细胞仪进行细胞周期测定.[结果]30种化合物中有27种化合物对Sf9细胞有抑制效果,其中吗啉丙烯酮类化合物A3、A4、A6的抑制率超过50%,分别为(69.5±1.54)%、(67.9±1.87)%与(53.6±0.98)%.用50 μmol/L的化合物A3处理Sf9细胞后,有凋亡小体出现.同时,化合物A3能干扰细胞正常的增殖周期,使部分细胞被阻滞在DNA合成期(S期).[结论]化合物A3、A4、A6对Sf9细胞有较强的抑制作用,化合物A3可以干扰正常的细胞周期,并引发细胞凋亡.

  18. Temperature effects on the mating frequency of Anticarsia gemmatalis Huebner and Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae); Influencia da temperatura na frequencia de copula de Anticarsia gemmatalis Huebner e Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)

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    Milano, Patricia; Berti Filho, Evoneo [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. Entomologia, Fitopatologia e Zoologia Agricola. Lab. de Entomologia Florestal; Parra, Jose R.P. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. Entomologia, Fitopatologia e Zoologia Agricola. Lab. Biologia de Insetos; Consoli, Fernando L. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. Entomologia, Fitopatologia e Zoologia Agricola. Lab. de Ecologia Nutricional e Molecular de Interacoes entre Artropodes e Microrganismos]. E-mails: patmilano@gmail.com; eberti@esalq.usp.br; jrpparra@esalq.usp.br; fconsoli@esalq.usp.br

    2008-09-15

    This paper deals with the influence of temperature on the mating frequency of two lepidopterans, Anticarsia gemmatalis Huebner and Spodoptera frugiperda (J.E. Smith), which use different strategies of allocation, and with the utilization of nutrients for their reproductive activities. The insects were reared on artificial diets at 25 deg C, and the adults were exposed to five temperatures (15, 20, 25, 30, and 35 deg C) to observe the influence of each temperature on their mating frequency, fecundity, fertility and longevity. The temperature affected the mating frequency of both species, being more evident at 15 deg C and 35 deg C, mainly for A. gemmatalis, which presented a drastic reduction on mating activities. The highest number of matings were observed from 20 deg C to 30 deg C, with S. frugiperda presenting mating activity (0-8) much higher than that of A. gemmatalis (0-2), but no correlation was observed among the number of matings and all other biological parameters evaluated (fecundity, fertility and longevity). However, S. frugiperda showed a positive correlation between fecundity and mating activity of females (r = 0.589; P = 0.003) at 25 deg C. The highest fecundities were observed at temperatures from 20 deg C to 30 deg C for S. frugiperda and at 25 deg C for A. gemmatalis. For both species, the longevity of males and females decreased as temperature increased. (author)

  19. Biologia de Spodoptera frugiperda (J. E. Smith (Lepidoptera: Noctuidae em Algodoeiro de Fibra Colorida Tratado com Silício

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    Alex Silva

    2014-04-01

    Abstract. The caterpillar Spodoptera frugiperda (Smith is a key pest of the corn culture and each year its occurrence in the cotton culture has increased, causing severe damage from the seedling phase to maturation. The objective of this work was to evaluate the effect of the silicon on the biology of S. frugiperda in white and colored fiber cotton plants. The bioassays were conducted with two cultivars of cotton, BRS Cedro (white fibers and BRS Verde (green fibers, with and without silicon application. The silicon was applied as a solution of 1% silicon acid, at a dosage equivalent to 3 ton/ha of SiO2. The following biological parameters were evaluated: larval mortality, duration of the larval and pupal phase, pupal viability, pupal weight, gender ratio, adult longevity of males and females and the number of eggs/female. It was verified that the silicon application only increased the mortality of caterpillars fed with BRS Cedro leaves, not demonstrating any effect on the caterpillars when applied on BRS Verde. Furthermore, the BRS Cedro cultivar, when compared to the BRS Verde cultivar, presented a lower pupal weight and a lower eggs/female production.

  20. Enzymatic activity of α-amylase in alimentary tract Spodoptera littoralis (Boisduval (Lepidoptera: Noctuidae: Characterization and Compartmentalization

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    Ali Darvishzadeh

    2014-09-01

    Full Text Available The Egyptian cotton leafworm, Spodoptera littoralis (Boisduval (Lepidoptera: Noctuidae damages a wide variety of crops in Middle East. Their hosts include cotton, alfalfa, eggplant, tomato, lettuce, bean and some ornamental crops. The intensive use of broad-spectrum insecticides against S. littoralis has led to the development of resistance to many registered pesticides use for its control. The purpose of the present study is biochemical characterization of digestive enzymes of this pest to gain a better understanding of the digestive physiology. The physiology and biochemistry of the insect digestive enzyme had an important role in the study of novel insecticidal strategies. The Egyptian cotton leafworm alimentary canal consists of a short foregut, a long midgut and a short hindgut. Application of pH indicators showed that alimentary canal was alkaline. Our results showed that activities of gut α-amylase were different in three parts of the insect gut. Also shown the greatest activity of α-amylase observed in the midgut followed by hindgut and foregut, respectively. However, there were not significant differences in activity of the enzyme in the midgut and hindgut. The optimal pH α-amylase in foregut, midgut and hindgut were 10.0. Zymogram analysis of different part of gut showed four bands in midgut, hind gut and two bands in foregut. Therefore, in midgut of S. littoralis, four isoenzymes were present. These results explain why more amylase activity was seen in these regions in the spectrophotometric assay.

  1. Identification of plant semiochemicals and characterization of new olfactory sensory neuron types in a polyphagous pest moth, Spodoptera littoralis.

    Science.gov (United States)

    Binyameen, Muhammad; Anderson, Peter; Ignell, Rickard; Birgersson, Göran; Razaq, Muhammad; Shad, Sarfraz A; Hansson, Bill S; Schlyter, Fredrik

    2014-10-01

    Phytophagous insects use blends of volatiles released from plants to select hosts for feeding and oviposition. To behaviorally analyze complex blends, we need efficient and selective methods for elucidating neuron types, their ligands, and specificity. Gas chromatography-combined single sensillum recordings (GC-SSRs) from antennal olfactory sensilla of female moth, Spodoptera littoralis revealed 38 physiologically active peaks in the headspace volatile blends from both larvae-damaged cotton plants and lilac flowers. Using GC-combined mass spectrometry, 9 new physiologically active compounds were identified from damaged cotton and 11 from lilac compared with earlier electrophysiological studies using antennae of female S. littoralis. We characterized 14 novel classes of olfactory sensory neurons (OSNs). Among these, we found the first 2 ligands for a frequent type of short trichoid sensillum, for which no ligands were identified earlier. By using GC-SSR, a substantial increase in functional classes of OSNs and active compounds, 40% and 34% more, respectively, compared with recent studies using GC-electroantennogram or SSR using single compounds was detected. Compared with the estimated number of corresponding antennal olfactory receptors, the OSN classes now correspond to 83% of a likely maximum. The many specialist OSNs observed may facilitate behavioral confirmation of key plant volatiles in blends.

  2. Purification and characterization of biliverdin-binding vitellogenin from the hemolymph of the common cutworm, Spodoptera litura.

    Science.gov (United States)

    Maruta, Kousei; Yoshiga, Toyoshi; Katagiri, Chihiro; Ochiai, Masanori; Tojo, Sumio

    2002-06-01

    Biliverdin-binding vitellogenin (Vg) was purified from adult female hemolymph of the common cutworm, Spodoptera litura, by using gel filtration and ion exchange chromatographies. The molecular mass of the protein was 490 kDa and it was composed of two 188-kDa subunits. Three internal amino acid sequences obtained by digestion of the protein with lysylendopeptidase showed high similarity to those of Bombyx mori Vg, supporting the purified blue protein to be vitellogenin. latroscan analyses demonstrated the presence of biliverdin in Vg that occupied 2.4% of total lipid components. Among the lipids of Vg (9.5 micrograms total lipids per 100 micrograms protein), diacylglycerol was the most predominant, followed by phospholipid, hydrocarbons, and then triacylglycerol, while in biliverdin-binding proteins (BPs) purified from larval hemolymph (3.1 micrograms total lipids per 100 micrograms protein), phospholipid was the most abundant lipid followed by diacylglycerol; hydrocarbons and triacylglycerol were minor components. Vg was first detected in the hemolymph of female pupae one day before eclosion, but injection of 5 micrograms of methoprene into a 3-day-old pupa induced Vg in the hemolymph 4 days earlier than in the control. Methoprene also induced a faster decline in BP-A and BP-B titers in the hemolymph with a corresponding increase of the Vg titer. These results suggest that juvenile hormone (JH) induces not only vitellogenesis but also the uptake of these proteins by stimulating the metamorphosis of fat body during the pupal stage.

  3. Pesticidal activity of Rivina humilis L. (Phytolaccaceae against important agricultural polyphagous field pest, Spodoptera litura (Fab. (Lepidoptera: Noctuidae

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    Elumalai Arumugam

    2015-05-01

    Full Text Available Objective: To evaluate the pesticidal activity of antifeedant, oviposition deterrent, ovicidal and larvicidal activities of benzene, dichloromethane, diethylether, ethylacetate and methanol extracts of Rivina humilis at different concentrations against agricultural polyphagous pest Spodoptera litura (Lepidoptera: Noctuidae (S. litura. Methods: Antifeedant activities of the selected plant extract were studied as described by Isman et al. (1990, with slight modifications. For oviposition deterrent activity, ten pairs of (adult moths S. litura were subjected in five replicates. After 48 h, the numbers of eggs masses laid on treated and control leaves were recorded and the percentage of oviposition deterrence was calculated. The ovicidal activity was determined against the eggs of S. litura. Twenty five early fourth instar larvae of S. litura were exposed to various concentrations and was assayed by using the protocol of Abbott’s formula (1925; the 24 h LC50 values of the Rivina humilis leaf extract was determined by probit analysis. Results: All the extracts showed moderate antifeedant activitiy; however, significant antifeedant, ovicidal, oviposition deterrent and larvicidal activities were observed in methanol extract. Conclusions: This study showed that the selected plant can be a potent source of natural antifeedant, oviposition deterrent, ovicidal and larvicidal activities against field pest S. litura.

  4. Chemical constituents and ovicidal effects of mahlab, Prunus mahaleb L. kernels oil on cotton leafworm, Spodoptera littoralis (Boisd. eggs

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    Mead Hala M.

    2016-07-01

    Full Text Available The carried out investigations evaluated ovicidal activity of mahlab, Prunus mahaleb L. kernel oil against cotton leafworm, Spodoptera littoralis (Boisd.. The chemical constituents of the fixed oil of mahlab were analyzed using gas-liquid chromatography (GLC. Timnodonic (33.07%, oleic (28.71% and linoleic (24.35% were the basic fatty acids, while the major hydrocarbon and sterol were found to be heneicosane (62.57% and β-sitosterol (10.57%. The LC50 values for the one-day-old egg masses were found to be more susceptible than 3-day-old ones. Moreover, the leaf dip technique occurred to be more efficient than spraying technique. The results also showed abnormalities in the external morphology of egg shell, chorion surface, shell imprints and aeropyles of S. littoralis eggs treated with mahlab and KZ oils as compared to a control by using scanning electron microscope. Generally, the tested oils significantly reduced the activities of transaminase enzymes (AST and ALT, acid and alkaline phosphatases and total soluble protein except mahlab oil on acid phosphatase as compared to a control. Additionally, the oils of both mahlab and KZ oil affected some biological aspects such as incubation period, larval duration, larval mortality and pupal weight comparing to a control.

  5. Ovicidal activity of botanical oil formulations against Helicoverpa armigera Hubner and Spodoptera litura Fabricius (Lepidoptera:Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    Susaimanickam Maria Packiam; Kathirvelu Baskar; Savarimuthu Ignacimuthu

    2012-01-01

    Objective: To evaluate the ovicidal activity of different botanical oil formulations againstHelicoverpa armigera and Spodoptera litura. Methods: Different botanical oils were formulated with different ratio to evaluate the ovicidal activity against H. armigera and S. litura at 5, 10, 15 and 20μl/L concentrations. Results: All the oil formulations showed the ovicidal activity against H. armigera and S. litura. The maximum ovicidal actvity of 76.74 and 69.36% was noticed at 20μl/L concentration in formulation 3 PONNEEM. Formulation 4 Pongam oil showed lower ovicidal activity of 31.34 and 24.76% against H. armigera and S. litura respectively. Among the formulations, PONNEEM exhibited statistically superior ovicidal activity against both insect pests. Conclusions: the present study clearly showed PONNEEM as a pontenial biopesticide to control the egg stage of economically important pests of H. armigera and S. litura. This is the first report for the ovicidal activity of PONNEEM against these two insect pests.

  6. Pesticidal activity of Rivina humilis L. (Phytolaccaceae) against important agricultural polyphagous field pest, Spodoptera litura (Fab.) (Lepidoptera:Noctuidae)

    Institute of Scientific and Technical Information of China (English)

    Elumalai Arumugam; Backiyaraj Muthusamy; Kasinathan Dhamodaran; Mathivanan Thangarasu; Krishnappa Kaliyamoorthy; Elumalai Kuppusamy

    2015-01-01

    Objective: To evaluate the pesticidal activity of antifeedant, oviposition deterrent, ovicidal and larvicidal activities of benzene, dichloromethane, diethylether, ethylacetate and methanol extracts of Rivina humilis at different concentrations against agricultural polyphagous pest Spodoptera litura (Lepidoptera: Noctuidae) (S. litura). Methods: Antifeedant activities of the selected plant extract were studied as described by Isman et al. (1990), with slight modifications. For oviposition deterrent activity, ten pairs of (adult moths) S. litura were subjected in five replicates. After 48 h, the numbers of eggs masses laid on treated and control leaves were recorded and the percentage of oviposition deterrence was calculated. The ovicidal activity was determined against the eggs of S. litura. Twenty five early fourth instar larvae of S. litura were exposed to various concentrations and was assayed by using the protocol of Abbott’s formula (1925); the 24 h LC50 values of the Rivina humilis leaf extract was determined by probit analysis. Results: All the extracts showed moderate antifeedant activitiy; however, significant antifeedant, ovicidal, oviposition deterrent and larvicidal activities were observed in methanol extract. Conclusions: This study showed that the selected plant can be a potent source of natural antifeedant, oviposition deterrent, ovicidal and larvicidal activities against field pest S. litura.

  7. Responses of the cutworm Spodoptera litura (Lepidoptera: Noctuidae) to two Bt corn hybrids expressing Cry1Ab

    Science.gov (United States)

    Yinghua, Shu; Yan, Du; Jin, Chen; Jiaxi, Wei; Jianwu, Wang

    2017-01-01

    To examine the responses of the secondary lepidopteran pest Spodoptera litura to two Bacillus thuringiensis (Bt) corn hybrids [5422Bt1 (Event Bt11), 5422CBCL (MON810)] expressing Cry1Ab, larval bioassays with Cry1Ab toxin, corn leaves or kernels and bagging on corn plants were conducted. The results showed that larvae displayed a similar performance when fed kernels, but not leaves of 5422Bt1, 5422CBCL and their near-isogenic non-Bt corn (5422). Significantly higher Cry1Ab amounts were detected in larvae fed leaves than kernels of both Bt hybrids, with different molecular weights of protein band in plants (72 and 90 kDa for 5422Bt1 and 5422CBCL, respectively), gut contents (65 kDa), feces (50 kDa), which indicated that larvae had lower ingestion, higher degradation and excretion of Cry1Ab when fed kernels not leaves of both Bt hybrids. Significantly higher levels of cadherin-like receptors and alkaline phosphatase transcripts were detected in larvae fed leaves than kernels of two Bt hybrids. Catalase, superoxide dismutase and glutathione-S-transferase activities in larvae fed 5422Bt1 leaves were significantly higher than that of 5422 treatments. Therefore, S. litura had low susceptibility to 5422Bt1 and 5422CBCL when larvae fed kernels not leaves of Bt corn. Additionally, S. litura presented a much stronger tolerance to 5422CBCL than 5422Bt1. PMID:28186125

  8. Identification and characterization of a fatty acyl reductase from a Spodoptera littoralis female gland involved in pheromone biosynthesis.

    Science.gov (United States)

    Carot-Sans, G; Muñoz, L; Piulachs, M D; Guerrero, A; Rosell, G

    2015-02-01

    Fatty acyl-CoA reductases (FARs), the enzymes that catalyse reduction of a fatty acyl-CoA to the corresponding alcohol in insect pheromone biosynthesis, are postulated to play an important role in determining the proportion of each component in the pheromone blend. For the first time, we have isolated and characterized from the Egyptian cotton leaf worm Spodoptera littoralis (Lepidoptera: Noctuidae) a FAR cDNA (Slit-FAR1), which appeared to be expressed only in the pheromone gland and was undetectable in other female tissues, such as fat body, ovaries, wings, legs or thorax. The encoded protein has been successfully expressed in a recombinant system, and the recombinant enzyme is able to produce the intermediate fatty acid alcohols of the pheromone biosynthesis of S. littoralis from the corresponding acyl-CoA precursors. The kinetic variables Km and Vmax, which have been calculated for each acyl-CoA pheromone precursor, suggest that in S. littoralis pheromone biosynthesis other biosynthetic enzymes (e.g. desaturases, acetyl transferase) should also contribute to the final ratio of components of the pheromone blend. In a phylogenetic analysis, Slit-FAR1 appeared grouped in a cluster of other FARs involved in the pheromone biosynthesis of other insects, with little or non-specificity for the natural pheromone precursors.

  9. Oligosaccharide processing in the expression of human plasminogen cDNA by lepidopteran insect (Spodoptera frugiperda) cells

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, D.J.; Fraser, M.J.; Castellino, F.J. (Univ. of Notre Dame, IN (USA))

    1990-06-12

    A comparison has been made between the Asn{sup 289}-linked oligosaccharide structures of human plasma plasminogen and a recombinant human plasminogen, expressed in lepidopteran insect (Spodoptera frugiperda) cells, after infection of these cells with a recombinant baculovirus containing the entire human plasminogen cDNA. Using anion-exchange liquid chromatography mapping of the oligosaccharide units cleaved from the proteins by glycopeptidase F, compared with elution positions of standard oligosaccharide structures, coupled with monosaccharide compositional analysis, the authors find that the human plasma protein contained only bisialo-biantennary complex-type carbohydrate and asialo-biantennary complex carbohydrate, confirming earlier work published by this laboratory. The glycosylation pattern of the insect cell expressed recombinant human plasminogen showed considerable microheterogeneity, with identifiable high-mannose carbohydrate and truncated high-mannose oligosaccharide. Of major importance, approximately 40% of the oligosaccharide population consisted of complex carbohydrate (bisialo-biantennary), identical in structure with that of the human plasma protein. This the first direct identification of complex carbohydrate in proteins produced in insect cells and demonstrates that trimming and processing of high-mannose carbohydrate into complex-type oligosaccharide can occur. The data indicate that both normal and alternate pathways exist in these cells for incorporation and trimming of high-mannose oligosaccharides and that mannosidases, as well as galactosyl-, hexosaminidasyl-, and sialyltransferases are present, and/or can be induced, in these cells. From these observations, the authors conclude that amino acid sequences and/or protein conformational properties can control oligosaccharide processing events.

  10. Detection on emamectin benzoate-induced apoptosis and DNA damage in Spodoptera frugiperda Sf-9 cell line.

    Science.gov (United States)

    Wu, Xiwei; Zhang, Lei; Yang, Chao; Zong, Mimi; Huang, Qingchun; Tao, Liming

    2016-01-01

    Emamectin benzoate (EMB), an important macrocyclic lactone insecticide that belongs to the avermectin family and possesses excellent potency in controlling pests, is non-carcinogenic and non-mutagenic conducted in rats and mice, but EMB-induced cytotoxicity and genotoxicity in arthropod insect have been seldom reported yet. In the present paper, we quantified the cytotoxicity of EMB through the detections on cell viability, DNA damage, and cell apoptosis in Spodoptera frugiperda Sf-9 cells in vitro. The results showed that EMB caused a concentration- and time-dependent reduction on the viability of Sf-9 cells, and the median inhibitory concentrations (IC50) were 3.34μM at 72h of exposure. The dual acridine orange/ethidium bromide staining showed that exposure to EMB induced a significant time- and concentration-dependent increase on cell apoptosis. The alkaline comet assay revealed that EMB induced significant increases on single-strand DNA breaks, and the percentage of γH2AX-positive cells represented a time- and concentration-dependent formation of DNA double-strand breaks in Sf-9 cells. Interestingly, the similar cytotoxic actions of EMB also went for the human cancerous HeLa cells as a control cell group. Data demonstrated the potential cytotoxic effect of EMB on Sf-9 cells that was significantly greater than the effect of hydrogen peroxide at the same concentrations.

  11. Microscopic analysis of Spodoptera frugiperda (Lepidoptera: Noctuidae) embryonic development before and after treatment with azadirachtin, lufenuron, and deltamethrin.

    Science.gov (United States)

    Correia, Alicely A; Wanderley-Teixeira, Valéria; Teixeira, Alvaro A C; Oliveira, José V; Gonçalves, Gabriel G A; Cavalcanti, MaríIia G S; Brayner, Fábio A; Alves, Luiz C

    2013-04-01

    The botanical insecticides, growth regulators, and pyrethroids have an effect on the biology of Spodoptera frugiperda (Smith). However, no emphasis has been given to the effect of these insecticides on embryonic development of insects, in histological level. Thus, this research aimed to examine by light and scanning electron microscopy S. frugiperda eggs and to describe the embryonic development, before and after immersion treatment, using commercial concentrations and lower concentrations than commercial ones, of the compounds lufenuron (Match), azadirachtin (AzaMax), and deltamethrin (Decis-positive control). For light microscopy semithin sections of eggs were used, and for scanning electron microscopy, images of the surface of eggs, treated and untreated with insecticides. The morphological characteristics of S. frugiperda eggs, in general, were similar to those described in the literature for most of the insects in the order Lepidoptera. Spherical eggs slightly flattened at the poles, with chorion, yolk, vitelline membrane, and embryo formation. In both microscopic analysis, we observed that insecticides acted immediately and independent of concentration, resulting absence, or incomplete embryo, presented yolk granules widely dispersed, without vitellophage formation, chorion disintegration, disorganized blastoderm, presenting vacuoles, yolk region with amorphous cells, and formation of completely uncharacterized appendages. Thus, we conclude that the compounds lufenuron and azadirachtin interfere on S. frugiperda embryonic development.

  12. Development of insect resistant maize plants expressing a chitinase gene from the cotton leaf worm, Spodoptera littoralis.

    Science.gov (United States)

    Osman, Gamal H; Assem, Shireen K; Alreedy, Rasha M; El-Ghareeb, Doaa K; Basry, Mahmoud A; Rastogi, Anshu; Kalaji, Hazem M

    2015-12-14

    Due to the importance of chitinolytic enzymes for insect, nematode and fungal growth, they are receiving attention concerning their development as biopesticides or chemical defense proteins in transgenic plants and as microbial biocontrol agents. Targeting chitin associated with the extracellular matrices or cell wall by insect chitinases may be an effective approach for controlling pest insects and pathogenic fungi. The ability of chitinases to attack and digest chitin in the peritrophic matrix or exoskeleton raises the possibility to use them as insect control method. In this study, an insect chitinase cDNA from cotton leaf worm (Spodoptera littoralis) has been synthesized. Transgenic maize plant system was used to improve its tolerance against insects. Insect chitinase transcripts and proteins were expressed in transgenic maize plants. The functional integrity and expression of chitinase in progenies of the transgenic plants were confirmed by insect bioassays. The bioassays using transgenic corn plants against corn borer (Sesamia cretica) revealed that ~50% of the insects reared on transgenic corn plants died, suggesting that transgenic maize plants have enhanced resistance against S. cretica.

  13. Homologs to Cry toxin receptor genes in a de novo transcriptome and their altered expression in resistant Spodoptera litura larvae.

    Science.gov (United States)

    Gong, Liang; Wang, Huidong; Qi, Jiangwei; Han, Lanzhi; Hu, Meiying; Jurat-Fuentes, Juan Luis

    2015-07-01

    Insect resistance threatens sustainability of insecticides based on Cry proteins from the bacterium Bacillus thuringiensis (Bt). Since high levels of resistance to Cry proteins involve alterations in Cry-binding midgut receptors, their identification is needed to develop resistance management strategies. Through Illumina sequencing we generated a transcriptome containing 16,161 annotated unigenes for the Oriental leafworm (Spodoptera litura). Transcriptome mining identified 6 contigs with identity to reported lepidopteran Cry toxin receptors. Using PCR we confirmed their expression during the larval stage and compared their quantitative expression in larvae from susceptible and a field-derived Cry1Ca resistant strain of S. litura. Among reduced transcript levels detected for most tested contigs in the Cry1Ca-resistant S. litura larvae, the most dramatic reduction (up to 99%) was detected for alkaline phosphatase contigs. This study significantly expands S. litura transcriptomic resources and provides preliminary identification of putative receptor genes with altered expression in S. litura resistant to Cry1Ca toxin.

  14. Diurnal rhythm in expression and release of yolk protein in the testis of Spodoptera littoralis (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Kotwica, Joanna; Joachimiak, Ewa; Polanska, Marta A; Majewska, Magdalena M; Giebultowicz, Jadwiga M; Bebas, Piotr

    2011-04-01

    Circadian clocks (oscillators) regulate multiple life functions in insects. The circadian system located in the male reproductive tract of Lepidoptera is one of the best characterized peripheral oscillators in insects. Our previous research on the cotton leafworm, Spodoptera littoralis, demonstrated that this oscillator controls the rhythm of sperm release from the testis and coordinates sperm maturation in the upper vas deferens (UVD). We demonstrated previously that a protein that functions as yolk protein in females is also produced in cyst cells surrounding sperm bundles in the testis, and is released into the UVD. Here, we investigated the temporal expression of the yolk protein 2 (yp2) gene at the mRNA and protein level in the testis of S. littoralis, and inquired whether their expression is regulated by PER-based molecular oscillator. We describe a circadian rhythm of YP2 accumulation in the UVD seminal fluid, where this protein interacts with sperm in a circadian fashion. However, we also demonstrate that yp2 mRNA and YP2 protein levels within cyst cells show only a diurnal rhythm in light/dark (LD) cycles. These rhythms do not persist in constant darkness (DD), suggesting that they are non-circadian. Interestingly, the per gene mRNA and protein levels in cyst cells are rhythmic in LD but not in DD. Nevertheless, per appears to be involved in the diurnal timing of YP2 protein accumulation in cyst cells.

  15. Spatial variation in foliar chemicals within radish (Raphanus sativus) plants and their effects on performance of Spodoptera litura.

    Science.gov (United States)

    Yadav, Jitendra; Tan, Ching-Wen; Hwang, Shaw-Yhi

    2010-12-01

    Foliar chemicals are variable within a plant and this may affect herbivore feeding preference. This study was carried out to quantify concentrations of primary (nitrogen, water, and total nonstructural carbohydrates) and secondary substances (sinigrin) in young and old leaves of Raphanus sativus L. and to evaluate performance and survival of a generalist herbivore Spodoptera litura F. feeding on them. Forty to 50-d-old R. sativus plants were used in both foliar chemical analysis and insect performance bioassays. Leaves located on the third to the sixth node from the base of the plant were defined as old leaves and the remaining leaves (from seventh node to the plant apex) of the plant were referred as young leaves in this study. All foliar chemicals except water differed significantly between young and old leaves. Moreover, young leaves were more nutritious but much more defended, based on sinigrin content, against S. litura than old leaves. Performance and survival of S. litura were reduced on young leaves as compared with old leaves. Male and female larval duration only differed significantly on young leaves. Female larval development time was longer than male development time on young leaves, but not on older leaves. Therefore, this study revealed that defenses in young leaves have differential effects upon male and female S. litura.

  16. Metallothionein expression induced by nickel accumulation in the midgut of Spodoptera litura Fabricius larvae exposed to nickel

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Metallothionein expression induced by nickel accumulation in the midgut of Spodoptera litura Fabricius larvae was investigated by exposing S. litura larvae to the artificial diets amended with different doses of nickel for 3 generations. Nickel accumulations in the midgut of 6th instar larvae were detected by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), and the induced metallothionein expression in the midgut of 5th and 6th instar larvae in 120 h were quantified using cadmium-hemoglobin total saturation methods. The accumulated nickel in the midgut of the 6th instar larvae within a generation increased with the increase of the nickel doses in the treated diets and showed significant dose-dependence with the nickel doses in diets. Metallothioneins induced by nickel accumulated in the larval midgut also increased with nickel doses in diets and with the increasing stressing time in a generation. Results also suggested that the metallothionein expression was different with the time of S. litura larvae stressed by nickel.

  17. Nickel accumulation and its effects on the survival rate of Spodoptera litura Fabricius under continuous nickel stress

    Institute of Scientific and Technical Information of China (English)

    SUN HongXia; SHU YingHua; TANG WenCheng; WANG Qi; ZHOU Qiang; ZHANG GuRen

    2007-01-01

    The artificial diets mixed with various concentrations of nickel were offered to the larvae of the phytophagous insect Spodoptera litura Fabricius for 3 generations. Nickel accumulations in the 6th instar larvae, pupae and newly emerged adults of the corresponding generations of S. litura were investigated by Inductively Coupled Plasma-Atomic Emission Spectrometer (ICP-AES), and the effects of nickel accumulations on the survival rate of S. litura were also evaluated by individual rearing. The results showed that nickel accumulated in the 6th instar larvae, pupae and adults of S. litura, and the accumulated nickel in all the tested developmental stages within a generation increased with the increase of the nickel doses in the treated diets and showed significant dose-dependent relationship with the nickel doses in the artificial diets. The results also indicated that the nickel accumulations in the 6th instar larvae, pupae, and newly emerged adults from the 3rd generation were higher than those from the 2nd generation, which were also higher than those from the 1st generation. Nickel concentrations in pupae and adults were significantly lower than those in larvae, which indicated that the excessive nickel might be excreted during metamorphosis. Furthermore, larval survival rate, pupation rate and eclosion rate of S. litura in the tested three generations all decreased with the increase of the nickel doses in the treated diets.

  18. Morphological changes induced by thermal treatment and gamma irradiation on the males' hind legs of Spodoptera littoralis (Noctuidae; Lepidoptera

    Directory of Open Access Journals (Sweden)

    Mai S. EL-Degwi

    2015-10-01

    Full Text Available External morphology of males' hind legs of Spodoptera littoralis subjected to thermal treatment (33 °C and 37 °C or/and irradiated with substerilizing doses of gamma radiation (75, 100 and 150 Gy were studied using scanning electron microscopy (SEM in the parental generation. Five types of sensilla have been distinguished; three types of trichoid sensilla (T1,T2 and T3, sensilla basiconica and sensilla auricillica, which are considered as olfactory chemoreceptors. Moreover, sensilla chaetica are contact chemoreceptors, whereas sensilla styloconica are thermo–hygro/gustatory mechanoreceptors. The impact of thermal treatment or/and gamma irradiation reflect a clear morphological change in S. littoralis legs'sensilla, claws, spurs and scales. Otherwise, the degree of deformity was thermal and dose dependent, as it increased with an increase of the degree of temperature and dose of irradiation applied. Substerilizing doses 75 and 100 Gy, either alone or combined with thermal treatment 33 °C, have low undesirable effects on the hind legs with successful mobility or courtship behavior. Consequently, synergistic effect of gamma radiation and thermal stress induced successful application in the integrated pest management program for controlling S. littoralis.

  19. Cytomegalovirus immediate-early promoter efficiently drives heterogeneous gene expression in Spodoptera frugiperda (Sf9) insect cells.

    Science.gov (United States)

    Li, S; Zhang, Q N; Zhang, X T; Zheng, X Y; Lv, Y F; Hao, Z M

    2014-03-05

    Recently, wide attention has been given to the potential of recombinant baculovirus as a gene transfer vehicle for mammalian gene therapy. In this study, we packaged the recombinant baculoviruses with cytomegalovirus immediate-early (CMV-IE) promoter in Spodoptera frugiperda (Sf9) insect cells, and found that the CMV-IE promoter could efficiently drive the exogenic gene expression in the cells 12 h post-infection (h.p.i.). The expression level at 72 h.p.i. was only around half of that driven by polyhedrin promoter (Ppolh). However, the biological activity of the reporter proteins at 72 h.p.i. were similar with that driven by Ppolh. In addition, the Sf9 cells transfected with CMV-IE-containing plasmids also expressed foreign genes, suggesting that the CMV-IE-directed heterogeneous gene expression in the Sf9 cells was baculovirus-independent. These results demonstrate that the CMV-IE promoter might be used as a regular promoter in Sf9 cells.

  20. Spinosad induces programmed cell death involves mitochondrial dysfunction and cytochrome C release in Spodoptera frugiperda Sf9 cells.

    Science.gov (United States)

    Yang, Mingjun; Wang, Bo; Gao, Jufang; Zhang, Yang; Xu, Wenping; Tao, Liming

    2017-02-01

    Spinosad, a reduced-risk insecticide, acts on the nicotinic acetylcholine receptors and the gamma-aminobutyric acid receptor in the nervous system of target insects. However, its mechanism of action in non-neural insect cells is unclear. This study aimed to evaluate mitochondrial functional changes associated with spinosad in Spodoptera frugiperda (Sf9) insect cells. Our results indicate that in Sf9 cells, spinosad induces programmed cell death and mitochondrial dysfunction through enhanced reactive oxygen species production, mitochondrial permeability transition pore (mPTP) opening, and mitochondrial membrane potential collapse, eventually leading to cytochrome C release and apoptosis. The cytochrome C release induced by spinosad treatment was partly inhibited by the mPTP inhibitors cyclosporin A and bongkrekic acid. Subsequently, we found that spinosad downregulated Bcl-2 expression and upregulated p53 and Bax expressions, activated caspase-9 and caspase-3, and triggered PARP cleavage in Sf9 cells. These findings suggested that spinosad-induced programmed cell death was modulated by mitochondrial dysfunction and cytochrome C release.

  1. Azadirachtin-induced apoptosis involves lysosomal membrane permeabilization and cathepsin L release in Spodoptera frugiperda Sf9 cells.

    Science.gov (United States)

    Wang, Zheng; Cheng, Xingan; Meng, Qianqian; Wang, Peidan; Shu, Benshui; Hu, Qiongbo; Hu, Meiying; Zhong, Guohua

    2015-07-01

    Azadirachtin as a kind of botanical insecticide has been widely used in pest control. We previously reported that azadirachtin could induce apoptosis of Spodoptera litura cultured cell line Sl-1, which involves in the up-regulation of P53 protein. However, the detailed mechanism of azadirachtin-induced apoptosis is not clearly understood in insect cultured cells. The aim of the present study was to address the involvement of lysosome and lysosomal protease in azadirachtin-induced apoptosis in Sf9 cells. The result confirmed that azadirachtin indeed inhibited proliferation and induced apoptosis. The lysosomes were divided into different types as time-dependent manner, which suggested that changes of lysosomes were necessarily physiological processes in azadirachtin-induced apoptosis in Sf9 cells. Interestingly, we noticed that azadirachtin could trigger lysosomal membrane permeabilization and cathepsin L releasing to cytosol. Z-FF-FMK (a cathepsin L inhibitor), but not CA-074me (a cathepsin B inhibitor), could effectively hinder the apoptosis induced by azadirachtin in Sf9 cells. Meanwhile, the activity of caspase-3 could also be inactivated by the inhibition of cathepsin L enzymatic activity induced by Z-FF-FMK. Taken together, our findings suggest that azadirachtin could induce apoptosis in Sf9 cells in a lysosomal pathway, and cathepsin L plays a pro-apoptosis role in this process through releasing to cytosol and activating caspase-3.

  2. Extrato aquoso de ramos de Trichilia pallida e o desenvolvimento de Spodoptera frugiperda em genótipos de milho

    Directory of Open Access Journals (Sweden)

    Torrecillas Sônia Martins

    2001-01-01

    Full Text Available Avaliaram-se o desenvolvimento e a sobrevivência da lagarta-do-cartucho, Spodoptera frugiperda (J. E. Smith criada em folhas de dois genótipos de milho (o padrão comercial C 901 e o resistente CMS 23 tratados com extratos aquosos (0,1 e 1% de ramos da planta inseticida Trichilia pallida Swartz (Meliaceae. As variáveis biológicas avaliadas foram peso, duração e viabilidade das fases larval e pupal. Em plantas tratadas com o extrato a 1%, ocorreu mortalidade total das lagartas nos dois genótipos, enquanto que a 0,1% o extrato reduziu a sobrevivência e o peso larval e prolongou o período de desenvolvimento. Lagartas alimentadas com o genótipo CMS 23 apresentaram menor sobrevivência, menor peso e maior período de desenvolvimento do que no genótipo C 901.

  3. Identification of midgut microvillar proteins from Tenebrio molitor and Spodoptera frugiperda by cDNA library screenings with antibodies.

    Science.gov (United States)

    Ferreira, A H P; Cristofoletti, P T; Lorenzini, D M; Guerra, L O; Paiva, P B; Briones, M R S; Terra, W R; Ferreira, C

    2007-11-01

    The objective of this study was to identify midgut microvillar proteins in insects appearing earlier (Coleoptera) and later (Lepidoptera) in evolution. For this, cytoskeleton-free midgut microvillar membrane from Spodoptera frugiperda (Lepidoptera) and Tenebrio molitor (Coleoptera) were used to raise antibodies. These were used for screening midgut cDNA expression libraries. Positive clones were sequenced, assembled and searched for similarities with gene/protein databases. The predicted midgut microvillar proteins from T. molitor were: cockroach allergens (unknown function), peritrophins (peritrophic membrane proteins), digestive enzymes (aminopeptidase, alpha-mannosidase) and unknown proteins. Predicted S. frugiperda midgut proteins may be grouped into six classes: (a) proteins involved in protection of midgut (thioredoxin peroxidase, aldehyde dehydrogenase, serpin and juvenile hormone epoxide hydrolase); (b) digestive enzymes (astacin, transporter-like amylase, aminopeptidase, and carboxypeptidase); (c) peritrophins; (d) proteins associated with microapocrine secretion (gelsolin, annexin); (e) membrane-tightly bound-cytoskeleton proteins (fimbrin, calmodulin) and (f) unidentified proteins. The novel approach is compared with others and microvillar function is discussed in the light of the predicted proteins.

  4. Determination and Analysis of Free Amino Acids in Nectar Source of Armyworm Moth%黏虫蜜源植物花蜜中游离氨基酸的测定与分析

    Institute of Scientific and Technical Information of China (English)

    刘保玲; 王高平; 胡京枝

    2012-01-01

    为探讨黏虫成虫与迁飞中转地蜜源植物的营养关系,利用氨基酸分析仪测定了其蜜源植物油菜和紫云英花蜜中游离氨基酸的种类和含量.结果显示,油菜和紫云英花蜜中都含17种氨基酸,油菜花蜜中游离氨基酸的总含量是紫云英花蜜的2.47倍.紫云英花蜜与油菜花蜜中各游离氨基酸的含量不同.油菜花蜜中除胱氨酸、蛋氨酸、苯丙氨酸、赖氨酸、精氨酸外,其他游离氨基酸的含量均比紫云英花蜜中相应的氨基酸高,其中丙氨酸、酪氨酸、丝氨酸、甘氨酸、天冬氨酸的含量分别是紫云英花蜜的14.36倍、11.35倍、5.70倍、4.69倍、4.11倍.研究还发现,紫云英蜂蜜中氨基酸总量是紫云英花蜜中氨基酸总量的4.29倍,油菜花蜜比油菜蜂蜜多含了胱氨酸和亮氨酸.因此,不能用油菜蜂蜜、紫云英蜂蜜代替油菜花蜜、紫云英花蜜来研究紫云英和油菜花蜜对黏虫的营养效应.%Milk vetch(Astragalus sinicus)and rape(Brassica napus) arc primary nectar plants for oriental armyworm (Mythimna separata ). Milk vetch was reported as a key factor resulting in severe outbreaks of oriental armyworm in China. This study collected nectar of milk vetch and rape by the capillary method,and then determined the type and content of free amino acids by the ami-no acid analyzer. Results showed that there were 17 amino acids in both rape nectar and milk vetch nectar. The total free amino acid content in rape nectar was 2. 47 times as much as the content in milk vetch nectar. The content of each free amino acid was different between milk vetch nectar and rape nectar: The content in rape nectar was higher than that of the corresponding ami-no acid in milk vetch nectar except Cys,Met,Phe,Lys, Arg;The contents of Ala,Tys,Ser,Gly, and Asp in rape nectar were 14. 36,11. 35,5. 70,4, 69,and 4. 11 times as much as those in milk vetch nectar. The total free amino acid content in milk vetch honey was 4. 29

  5. 东北粘虫春季空中虫群的迁飞行为%The spring migration behavior of the oriental armyworm, Mythimna separata, in northeastern China

    Institute of Scientific and Technical Information of China (English)

    高月波; 孙雅杰; 张强; 孙嵬; 周佳春

    2014-01-01

    Objectives To investigate the aerial stratification and common orientation of the spring migrant populations of the oriental armyworm Mythimna separata (Walker). [Methods] This study is based on spring radar data collected over two years, in combination with the analysis of meteorological factors and compass cues. [Results] Most moths trended to aggregate near the upper inversion surface in order to find warmer conditions. Moreover, M. separata moths had a lower temperature threshold (about 16°C) during the migration period when it had low population density and did not to aggregate under this temperature threshold. Furthermore, a significant correlation between migration direction and the wind speed was observed. When the wind was strong (>5 m/s) and closely aligned with the armyworm moths heading (i.e., toward the NE), M. separata generally orientated close to the downwind. When the wind speed was less (<3 m/s) and not closely aligned with the moths heading, M. separata compensated for the cross-wind drift and even flew upwind. On the other hand, the oriental armyworm may use some compass cues (e.g., geomagnetic compass) to orient its general flight direction, during migration. [Conclusion] The results provide some theoretical basis for the off-site forecasting of migratory insect pests.%研究春季迁飞粘虫Mythimna separata (Walker)空中虫群的聚集成层和共同定向等飞行行为。以2年粘虫迁飞盛期的雷达观测数据为基础,结合空间气象要素和罗盘信号分析。在温度较低的春季进行迁飞的粘虫多在逆温层顶附近聚集成层,空中虫群会主动选择高温。迁飞粘虫具有明显的飞行低温阈值(16℃左右),此温度以下空中虫群密度低、无聚集成层现象。空中虫群位移方向的离散度与风速呈显著负相关。当风速较大(大于5 m/s)且风向与粘虫迁飞方向(东北)相一致时,虫群通常表现为顺风定向;当风速小于3m/s且风向与

  6. Spodoptera litura Multicapsid Nucleopolyhedrovirus Blocks Autographa californica Multicapsid Nucleopolyhedrovirus-induced Spodoptera litura Cell Apoptosis%斜纹夜蛾核多角体病毒抑制苜蓿丫纹夜蛾核多角体病毒诱导的斜纹夜蛾细胞凋亡

    Institute of Scientific and Technical Information of China (English)

    张萍; 杨凯; 代小江; 庞义; 苏德明

    2002-01-01

    野生型苜蓿丫纹夜蛾核多角体病毒(Autographa californica multicapsid nucleopolyhedrovirus, AcMNPV)感染斜纹夜蛾(Spodoptera litura)细胞系Sl-zsu-1,可引起典型的细胞凋亡;但可以在草地夜蛾(Spodoptera frugiperda)细胞Sf-9中复制并形成多角体.比较了AcMNPV p35基因在病毒感染两种细胞的复制和转录情况,认为p35在非受纳细胞中及时有效的表达能阻止细胞发生凋亡;共感染实验结果表明,斜纹夜蛾核多角体病毒(Spodoptera litura multicapsid nucleopolyhedrovirus, SpltMNPV)可以抑制AcMNPV诱导的细胞凋亡并可帮助病毒进行复制,推测SpltMNPV基因组中与p35同源的p49基因挽救了细胞的自杀行为.

  7. Biologia comparada de Spodoptera cosmioides (Walk. (Lepidoptera: Noctuidae em cebola, mamona, soja e feijão Compared biology of Spodoptera cosmioides (Walk. (Lepidoptera: Noctuidae in onion, castor oil plant, soybean and bean

    Directory of Open Access Journals (Sweden)

    Alvimar Bavaresco

    2003-12-01

    Full Text Available Estudou-se a biologia de Spodoptera cosmioides (Walk. sobre quatro hospedeiros naturais (folhas de cebola, mamona, soja cv. Embrapa 48 e feijão cv. Carioca. Foram avaliados a duração e viabilidade das fases imaturas e do ciclo total, número de ínstares, peso de pupas, razão sexual, porcentagem de deformação de adultos e de adultos não liberados dos invólucros pupais, longevidade de adultos, fecundidade e viabilidade de ovos. Observou-se menor duração e maior viabilidade do período ovo-adulto para mamona e cebola (39,7 dias e 21,7% e 40,5 dias e 21,8%, respectivamente, do que para soja (46,0 dias e 3,9%. O peso pupal foi de 444,6 mg em cebola, 420,0 em feijão, 396,6 em mamona e 298,7 em soja. Constatou-se um predomínio de seis ínstares larvais em folhas de cebola e mamona, ocorrendo também sete para alguns indivíduos, enquanto que em soja predominou a ocorrência de sete, também verificando oito ínstares, indicando uma menor adequação nutricional deste hospedeiro. As fêmeas apresentaram duração da fase pupal significativamente menor do que os machos em todos hospedeiros, fazendo com que a emergência do adulto ocorresse antes dos machos. Em cebola, a longevidade de adultos foi significativamente superior aos demais hospedeiros. A fecundidade foi maior em cebola e mamona (3224 e 3206 ovos/fêmea, respectivamente, enquanto que para soja observou-se 1353 ovos/fêmea. Em folhas de feijão, o desenvolvimento do inseto foi prejudicado por caracteres morfológicos - pilosidade, que promoveram elevada mortalidade na fase larval.The biology of Spodoptera cosmioides (Walk. was studied on four natural hosts (onion leaves, castor oil plant, soy cv. Embrapa 48 and bean cv. Carioca. The duration and viability of immature phases and total cycle, instar number, pupals weight, sexual ratio, percentage of deformed adults and adults not released of pupal beg, adults' longevity, fecundity and eggs viability were evaluated. It was observed in

  8. Biologia e tabela de vida de fertilidade de Spodoptera eridania (Cramer (Lepidoptera: Noctuidae em morangueiro e videira Biology, fertility life table and effect of insecticides on Spodoptera eridania (Cramer (Lepidoptera: Noctuidae in strawberry and grape

    Directory of Open Access Journals (Sweden)

    Lígia Caroline Bortoli

    2012-12-01

    Full Text Available A biologia de Spodoptera eridania foi estudada em laboratório (22±1ºC, UR 70±10%, fotofase de 14 horas, em folhas de morangueiro (Fragaria x ananassa cv. 'Aromas' e videira (Vitis vinifera cv. 'Cabernet Sauvignon'. A duração e a viabilidade do ciclo total foram, respectivamente, de 52,2±1,32 dias e 37,6% para morangueiro e 42,2±0,45 dias e 25,5% para videira. A razão sexual em morangueiro foi de 0,58, e 0,48 em videira. A longevidade média de machos e fêmeas em morangueiro foi de 16,3±1,16 e 15,8±1,85 dias, respectivamente, e 5,6±0,88 e 7,3±0,83 dias em videira. A fecundidade média total foi de 1.747,5±187,32 ovos por fêmea em morangueiro, e 1.764,9±289,04 em videira. A tabela de vida de fertilidade mostrou que a taxa líquida de reprodução e a razão finita de aumento foram de 394,89 e 1,10, respectivamente, para morangueiro, e de 213,98 e 1,12 para videira. As culturas do morangueiro cv. 'Aromas' e da videira cv. 'Cabernet Sauvignon' são hospedeiras favoráveis e equivalentes quanto ao potencial de crescimento populacional de S. eridania.The biology of Spodoptera eridania was studied in the laboratory (22±1ºC, RH 70±10%, 14 hours of photoperiod in leaves of strawberry (Fragaria x ananassa cv. 'Aromas' and grape (Vitis vinifera cv. 'Cabernet Sauvignon'. The duration and viability of the entire cycle were respectively 52.2±1.32 days and 37.6% for strawberry and 42.2±0.45 days and 25.5% for grapes. The sex ratio in strawberry was 0.58 and 0.48 on grape. The average longevity of males and females in strawberry was 16.3±1.16 and 15.8±1.85 days, respectively, and 5.6±0.88 and 7.3±0.83 days in grape. The mean fecundity was 1,747.5±187.32 eggs per female in strawberry and 1,764.9±289.04 on grape. The life table of fertility showed that the net reproduction rate and finite rate of increase were 394.89 and 1.10, respectively, for strawberry and 213.98 and 1.12 for grapevine. Strawberry cv. 'Aromas' and grape cv

  9. SUSCEPTIBILIDAD DE Spodoptera frugiperda (J. E. Smith) (LEPIDOPTERA: NOCTUIDAE) A INSECTICIDAS ASOCIADA A CÉSPED EN QUINTANA ROO, MÉXICO

    OpenAIRE

    Imelda León-García; Esteban Rodríguez-Leyva; Ortega-Arenas, Laura D.; Juan F. Solís-Aguilar

    2012-01-01

    El gusano cogollero Spodoptera frugiperda es una de las principales plagas que ataca al maíz (Zea mays L.) y céspedes (Paspalum vaginatum Swartz, Cynodon dactylon (L.) Person) en el sur de EE.UU., México, Centro y Sudamérica. Este gusano causa daños al follaje y ocasionalmente pérdida de secciones de la carpeta, y su control se realiza mediante insecticidas. El objetivo de esta investigación fue determinar la susceptibilidad de S. frugiperda a insecticidas de uso común en campos de go...

  10. Transcriptional profiling analysis of Spodoptera litura larvae challenged with Vip3Aa toxin and possible involvement of trypsin in the toxin activation

    OpenAIRE

    Feifei Song; Chen Chen; Songqing Wu; Ensi Shao; Mengnan Li; Xiong Guan; Zhipeng Huang

    2016-01-01

    Vip proteins, a new group of insecticidal toxins produced by Bacillus thuringiensis, are effective against specific pests including Spodoptera litura. Here, we report construction of a transcriptome database of S. litura by de novo assembly along with detection of the transcriptional response of S. litura larvae to Vip3Aa toxin. In total, 56,498 unigenes with an N50 value of 1,853 bp were obtained. Results of transcriptome abundance showed that Vip3Aa toxin provoked a wide transcriptional res...

  11. Dominância funcional e monitoramento da resistência de Spodoptera frugiperda (J. E. Smith, 1797) (Lepidoptera: Noctuidae) a tecnologias Bt no Brasil

    OpenAIRE

    Renato Jun Horikoshi

    2016-01-01

    Plantas transgênicas que expressam toxinas de Bacillus thuringiensis Berliner (Bt) têm sido amplamente utilizadas para o controle de Spodoptera frugiperda (J. E. Smith) no Brasil. Entretanto, a evolução da resistência é um dos maiores entraves para a continuidade do uso desta tecnologia. Para subsidiar programas de Manejo da Resistência de Insetos (MRI), foram conduzidos estudos para o aprimoramento dos programas de manejo da resistência de S. frugiperda a tecnologias Bt. Foram realizadas est...

  12. Antifeedant, larvicidal and growth inhibitory effects of ononitol monohydrate isolated from Cassia tora L. against Helicoverpa armigera (Hub.) and Spodoptera litura (Fab.) (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Baskar, Kathirvelu; Ignacimuthu, Savarimuthu

    2012-07-01

    Ononitol monohydrate isolated from the ethyl acetate extract of Cassia tora L. using column chromatography was evaluated for its antifeedant, larvicidal and growth inhibitory activities against Helicoverpa armigera and Spodoptera litura at different concentrations of 125, 250, 500 and 1000 ppm. Leaf disc no-choice method was used for the bioassay. The compound showed significant antifeedant, larvicidal and pupicidal activities against H. armigera and S. litura. The compound also prolonged the larval-pupal duration of the insect at all the tested concentrations. The activities were concentration dependent for both the insects. Ononitol could be used as an agent to prepare botanical new pesticidal formulations.

  13. Adequação de uma dieta artificial para os biótipos "milho" e "arroz" de Spodoptera frugiperda (Lepidoptera: Noctuidae)

    OpenAIRE

    Busato,Gustavo Rossato; Garcia, Mauro Silveira; Loeck,Alci Enimar; Zart,Marcelo; Nunes,Adrise Medeiros; Bernardi, Oderlei; Andersson, Fabiana da Silva

    2006-01-01

    Spodoptera frugiperda é considerada uma das principais pragas da cultura do milho (lagarta-do-cartucho) e do arroz irrigado (lagarta-da-folha), ocasionando altos índices de desfolhamento. O objetivo do estudo foi obter uma dieta artificial adequada para criar os biótipos "milho" e "arroz" de S. frugiperda (J.E. Smith), em laboratório. Os insetos foram coletados em áreas cultivadas com milho e arroz irrigado no ecossistema de várzea e a identificação foi realizada pela análise do DNA genômico....

  14. Morphology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae (Lepidoptera: Noctuidae) fed on neem-treated leaves; Morfologia do canal alimentar de lagartas de Spodoptera frugiperda (J E Smith) (Lepidoptera: Noctuidae) alimentadas com folhas tratadas com nim

    Energy Technology Data Exchange (ETDEWEB)

    Correia, Alicely A.; Wanderley-Teixeira, Valeria; Oliveira, Jose V. de; Torres, Jorge B. [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Programa de Pos-Graduacao em Entomologia Agricola]. E-mail: aliceliac@yahoo.com.br; valeria@dmfa.ufrpe.br; Teixeira, Alvaro A.C. [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil). Dept. de Morfologia e Fisiologia Animal

    2009-01-15

    Research involving plants with insecticide activity evolved significantly in the last decades. Among these plants, the neem tree, Azadirachta indica, is commonly used against several insects, mainly Lepidoptera. The neem efficiency depends on the target insect and on the concentration used. A barrier against potential toxic agents ingested together with the food is the alimentary canal. Thus, this research aimed to describe the histology of the alimentary canal of Spodoptera frugiperda (J E Smith) larvae fed on leaves treated with neem (Neemseto{sup R}) at a concentration of 0.5% and 1.0% and non treated, at different intervals (48, 96, 144, 192 and 240 h), by quantifying the regenerative cells and analyzing the secretion of the mesenteron histochemically. Larvae were immobilized at low temperatures (-4 deg C), the alimentary canal was removed, fixed in Bouein's aqueous, embedded in paraplast and historesin, sectioned and stained with hematoxylin-eosin and periodic acid- Schiff. The histology of the alimentary canal of S. frugiperda was similar to other lepidopterans. Neem effects on morphology were seen only in the mesenteron, depending on the time and concentration used, such as: epithelium, reduction on regenerative cells and on the secretory activity in this region, confirmed by the histochemistry in both neem concentrations. These alterations were observed after 96 h at 1.0%, and 144 h at 0.5%. These results indicate that neem (Neemseto{sup R}), at the concentrations studied, may be effective to control S. frugiperda because it promotes meaningful morphological alterations in the mesenteron. (author)

  15. Interactions of Bacillus thuringiensis Cry1Ac toxin in genetically engineered cotton with predatory heteropterans.

    Science.gov (United States)

    Torres, Jorge B; Ruberson, John R

    2008-06-01

    A number of cotton varieties have been genetically transformed with genes from Bacillus thuringiensis (Bt) to continuously produce Bt endotoxins, offering whole plant and season-long protection against many lepidopteran larvae. Constant whole-plant toxin expression creates a significant opportunity for non-target herbivores to acquire and bio-accumulate the toxin for higher trophic levels. In the present study we investigated movement of Cry1Ac toxin from the transgenic cotton plant through specific predator-prey pairings, using omnivorous predators with common cotton pests as prey: (1) the beet armyworm, Spodoptera exigua (Lepidoptera: Noctuidae), with the predator Podisus maculiventris (Heteroptera: Pentatomidae); (2) the two-spotted spider mite, Tetranychus urticae (Acarina: Tetranychidae), with the predatory big-eyed bug Geocoris punctipes (Heteroptera: Geocoridae) and (3) with the predatory damsel bug Nabis roseipennis (Heteropera: Nabidae); and (4) the thrips Frankliniella occidentalis (Thysanoptera: Thripidae) with the predatory pirate bug Orius insidiosus (Heteroptera: Anthocoridae). We quantified Cry1Ac toxin in the cotton plants, and in the pests and predators, and the effects of continuous feeding on S. exigua larvae fed either Bt or non-Bt cotton on life history traits of P. maculiventris. All three herbivores were able to convey Cry1Ac toxin to their respective predators. Among the herbivores, T. urticae exhibited 16.8 times more toxin in their bodies than that expressed in Bt-cotton plant, followed by S. exigua (1.05 times), and F. occidentalis immatures and adults (0.63 and 0.73 times, respectively). Of the toxin in the respective herbivorous prey, 4, 40, 17 and 14% of that amount was measured in the predators G. punctipes, P. maculiventris, O. insidiosus, and N. roseipennis, respectively. The predator P. maculiventris exhibited similar life history characteristics (developmental time, survival, longevity, and fecundity) regardless of the prey's food

  16. Response of the common cutworm Spodoptera litura to zinc stress: Zn accumulation, metallothionein and cell ultrastructure of the midgut

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    Shu, Yinghua [Key Laboratory of Agro-Environments in Tropics, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642 (China); Key Laboratory of Agroecology and Rural Environment of Guangdong Regular Higher Education Institutions, South China Agricultural University, Guangzhou 510642 (China); Institute of Tropical and Subtropical Ecology, South China Agricultural University, Guangzhou 510642 (China); State Key Laboratory of Biological Control and Institute of Entomology, Sun Yat-sen University, Guangzhou 510275 (China); Zhang, Guren [State Key Laboratory of Biological Control and Institute of Entomology, Sun Yat-sen University, Guangzhou 510275 (China); Wang, Jianwu, E-mail: wangjw@scau.edu.cn [Key Laboratory of Agro-Environments in Tropics, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642 (China); Key Laboratory of Agroecology and Rural Environment of Guangdong Regular Higher Education Institutions, South China Agricultural University, Guangzhou 510642 (China); Institute of Tropical and Subtropical Ecology, South China Agricultural University, Guangzhou 510642 (China)

    2012-11-01

    By exposing the common cutworm Spodoptera litura Fabricius larvae to a range of Zinc (Zn) stress, we investigated the effects of dietary Zn on Zn accumulation, metallothionein (MT), and on the ultrastructure of the midgut. The techniques we used were inductively coupled plasma-atomic emission spectrometer (ICP-AES), real-time PCR combined with cadmium-hemoglobin total saturation, and transmission electron microscopy (TEM), respectively. There was a significant dose-response relationship between the Zn accumulations in the midgut of the larvae and the Zn concentrations in the diet. Furthermore, both MT content and MT gene expression in the midgut were significantly induced in the 50-500 mg Zn/kg treatments, and were significantly positively correlated with the Zn accumulations in the midgut. When S. litura larvae were fed with the diet treated with 500 mg Zn/kg, Zn accumulation and MT content in the midgut was 4450.85 mg Zn/kg and 372.77 mg/kg, respectively, thereafter there was a little increase; the level of MT gene expression was maximal, thereafter there was a sharp decrease. TEM showed that numerous electron-dense granules (EDGs) and vacuoles appeared in the cytoplasm of the midgut cells, their number and size being closely correlated with the Zn accumulations in the midgut. Moreover, the nuclei were strongly influenced by Zn stress, evidenced by chromatin condensation and irregular nuclear membranes. Therefore, after being exposed to Zn in the threshold (500 mg Zn/kg) range, S. litura larvae could accumulate Zn in the midgut, which led to the induction of MT and changes in cell ultrastructure (mainly the presence of EDGs). The induction of MT and precipitation of Zn in EDGs may be the effective detoxification mechanisms by which the herbivorous insect S. litura defends itself against heavy metals. -- Graphical abstract: When the herbivorous insect Spodoptera litura Fabricius larvae were fed on the artificial diet with different concentrations of Zn, amounts of

  17. Revisión de los hospederos del gusano cogollero del maíz, Spodoptera frugiperda (Lepidoptera: Noctuidae

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    Augusto CASMUZ

    2010-01-01

    Full Text Available Con la finalidad de actualizar los hospederos citados para Spodoptera frugiperda (J. E. Smith, se realizó una revisión bibliográfica. La búsqueda de hospederos fue agrupada por zona y país. Para el norte del Continente Americano, se incluyeron las citas encontradas para EE.UU., México, América Central e islas del Caribe. En Sudamérica, se agruparon todos los países del cono sur, a excepción de la Argentina, la cual fue considerada por separado. Se encontraron un total de 186 hospederos, repartidos en 42 familias. Entre los hospederos más citados, el 35,5% perteneció a la familia Poaceae, el 11,3% a la familia Fabaceae, a la familia Solanaceae y Asteraceae un 4,3 % cada una, siguiéndoles las Rosaceae y Chenopodiaceae con un 3,7% cada una y, finalmente, las Brassicaceae y Cyperaceae con un 3,2%. Del total de plantas encontradas (186 el 64% se hallaron presentes en Norteamérica y Centroamérica, un 53% en Sudamérica y un 32% en Argentina. Las especies más citadas fueron (en orden decreciente para Norteamérica: maíz, sorgo, maní, grama bermuda, caña de azúcar y arroz; para Sudamérica: maíz, arroz, sorgo, poroto, algodón y maní; y por último, en Argentina fueron: maíz, soja, algodón, alfalfa, tomate, lino, papa y sorgo. También se aporta información sobre su ciclo de vida, hábitos y comportamiento sobre los principales hospederos, migración y biotipos.

  18. Model and scenario variations in predicted number of generations of Spodoptera litura Fab. on peanut during future climate change scenario.

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    Mathukumalli Srinivasa Rao

    Full Text Available The present study features the estimation of number of generations of tobacco caterpillar, Spodoptera litura. Fab. on peanut crop at six locations in India using MarkSim, which provides General Circulation Model (GCM of future data on daily maximum (T.max, minimum (T.min air temperatures from six models viz., BCCR-BCM2.0, CNRM-CM3, CSIRO-Mk3.5, ECHams5, INCM-CM3.0 and MIROC3.2 along with an ensemble of the six from three emission scenarios (A2, A1B and B1. This data was used to predict the future pest scenarios following the growing degree days approach in four different climate periods viz., Baseline-1975, Near future (NF -2020, Distant future (DF-2050 and Very Distant future (VDF-2080. It is predicted that more generations would occur during the three future climate periods with significant variation among scenarios and models. Among the seven models, 1-2 additional generations were predicted during DF and VDF due to higher future temperatures in CNRM-CM3, ECHams5 & CSIRO-Mk3.5 models. The temperature projections of these models indicated that the generation time would decrease by 18-22% over baseline. Analysis of variance (ANOVA was used to partition the variation in the predicted number of generations and generation time of S. litura on peanut during crop season. Geographical location explained 34% of the total variation in number of generations, followed by time period (26%, model (1.74% and scenario (0.74%. The remaining 14% of the variation was explained by interactions. Increased number of generations and reduction of generation time across the six peanut growing locations of India suggest that the incidence of S. litura may increase due to projected increase in temperatures in future climate change periods.

  19. Biologia e tabela de vida de fertilidade de Spodoptera eridania (Cramer (Lepidoptera: Noctuidae em morangueiro e videira

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    Lígia Caroline Bortoli

    2012-12-01

    Full Text Available A biologia de Spodoptera eridania foi estudada em laboratório (22±1ºC, UR 70±10%, fotofase de 14 horas, em folhas de morangueiro (Fragaria x ananassa cv. 'Aromas' e videira (Vitis vinifera cv. 'Cabernet Sauvignon'. A duração e a viabilidade do ciclo total foram, respectivamente, de 52,2±1,32 dias e 37,6% para morangueiro e 42,2±0,45 dias e 25,5% para videira. A razão sexual em morangueiro foi de 0,58, e 0,48 em videira. A longevidade média de machos e fêmeas em morangueiro foi de 16,3±1,16 e 15,8±1,85 dias, respectivamente, e 5,6±0,88 e 7,3±0,83 dias em videira. A fecundidade média total foi de 1.747,5±187,32 ovos por fêmea em morangueiro, e 1.764,9±289,04 em videira. A tabela de vida de fertilidade mostrou que a taxa líquida de reprodução e a razão finita de aumento foram de 394,89 e 1,10, respectivamente, para morangueiro, e de 213,98 e 1,12 para videira. As culturas do morangueiro cv. 'Aromas' e da videira cv. 'Cabernet Sauvignon' são hospedeiras favoráveis e equivalentes quanto ao potencial de crescimento populacional de S. eridania.

  20. Deleterious activity of natural products on postures of Spodoptera frugiperda (Lepidoptera: Noctuidae) and Diatraea saccharalis (Lepidoptera: Pyralidae).

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    Tavares, Wagner S; Cruz, Ivan; Fonseca, Felipe G; Gouveia, Natalia L; Serrão, José E; Zanuncio, José C

    2010-01-01

    The control of Lepidoptera pests should be carried out before hatching of their caterpillars to avoid damage to the crops. The aim of this work was to assess the activity of neem (trade name: Natuneem, producer: Base Fértil, Chapadão do Sul, Brazil) and pyroligneous extracts (trade name: Biopirol 7M, producer: Biocarbo, Itabirito, Brazil) at 10 mL/L (1%) and 20 mL/L (2%) contents on egg masses of different ages of Spodoptera frugiperda Smith (Lepidoptera: Noctuidae) and of Diatraea saccharalis F. (Lepidoptera: Pyralidae) at Embrapa Corn and Sorghum in Sete Lagoas, Minas Gerais State, Brazil. The tests took place in an unbiased casualized design with 12 treatments and four replications. The insecticides were diluted in water, and 0.04 mL of the solution was applied to recently laid and one- and two-day-old eggs of S. frugiperda and D. saccharalis. Caterpillars hatching from recently laid egg masses of S. frugiperda was lower with 2% pyroligneous extract [(0.02 +/- 0.00)%]. Recently laid eggs and one- or two-day-old eggs of D. saccharalis presented lower caterpillar hatching with 1% neem extract [(0.00 +/- 0.00)%, (0.00 +/- 0.00)%, and (1.00 +/- 0.01)%] and 2% neem extract [(0.00 +/- 0.00)%], compared to 1% pyroligneous extract [(27.30 +/- 3.22)%, (28.40 +/- 3.32)%, and (37.80 +/- 4.14)%] and 2% pyroligneous extract [(42.20 +/- 4.49)%, (48.70 +/- 4.97)%, and (56.60 +/- 5.52)%], respectively. Neem and pyroligneous extracts had impact on hatching of S. frugiperda and D. saccharalis caterpillars.

  1. Deletion Genotypes Reduce Occlusion Body Potency but Increase Occlusion Body Production in a Colombian Spodoptera frugiperda Nucleopolyhedrovirus Population

    Science.gov (United States)

    Barrera, Gloria; Williams, Trevor; Villamizar, Laura; Caballero, Primitivo; Simón, Oihane

    2013-01-01

    A Colombian field isolate (SfCOL-wt) of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV) is a mixture of different genotypes. To evaluate the insecticidal properties of the different genotypic variants, 83 plaque purified virus were characterized. Ten distinct genotypes were identified (named A through J). SfCOL-A was the most prevalent (71±2%; mean ± SE) showing a PstI restriction profile indistinguishable to that of SfCOL-wt. The remaining nine genotypes presented genomic deletions of 3.8 - 21.8 Kb located mainly between nucleotides 11,436 and 33,883 in the reference genome SfMNPV-B, affecting the region between open reading frames (ORFs) sf20 and sf33. The insecticidal activity of each genotype from SfCOL-wt and several mixtures of genotypes was compared to that of SfCOL-wt. The potency of SfCOL-A occlusion bodies (OBs) was 4.4-fold higher than SfCOL-wt OBs, whereas the speed of kill of SfCOL-A was similar to that of SfCOL-wt. Deletion genotype OBs were similarly or less potent than SfCOL-wt but six deletion genotypes were faster killing than SfCOL-wt. The potency of genotype mixtures co-occluded within OBs were consistently reduced in two-genotype mixtures involving equal proportions of SfCOL-A and one of three deletion genotypes (SfCOL-C, -D or -F). Speed of kill and OB production were improved only when the certain genotype mixtures were co-occluded, although OB production was higher in the SfCOL-wt isolate than in any of the component genotypes, or mixtures thereof. Deleted genotypes reduced OB potency but increased OB production of the SfCOL-wt population, which is structured to maximize the production of OBs in each infected host. PMID:24116220

  2. Indica rice cultivar IRGA 424, transformed with cry genes of B. thuringiensis, provided high resistance against Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Pinto, Laura Massochin Nunes; Fiuza, Lidia Mariana; Ziegler, Denize; De Oliveira, Jaime Vargas; Menezes, Valmir Gaedke; Bourrié, Isabelle; Meynard, Donaldo; Guiderdoni, Emmanuel; Breitler, Jean-Christophe; Altosaar, Illimar; Gantet, Pascal

    2013-12-01

    Plant expression of the entomopathogenic bacteria Bacillus thuringiensis cry gene has reduced the damage created by insect pests in several economically important cultures. For this study, we have conducted genetic transformation of the indica rice "IRGA 424", via Agrobacterium tumefaciens, using the B. thuringiensis cry1Aa and cry1B genes, with the objective of obtaining rice plants resistant to the insect pests from this culture. The gene constructions harbor the promoters maize proteinase inhibitor and ubiquitin. The results showed that high concentration of the hormone 2,4-dichlorophenoxyacetic acid and agarose as the gelling agent helped the production of embryogenic calli for the analyzed cultivar. More than 80% of the obtained transformed plants revealed the integration, using polymerase chain reaction, of the cry1Aa and cry1B genes. Analysis of the expression of the heterologous protein by Western blotting revealed the expression of the Cry1B delta-endotoxin in IRGA 424 plants transformed with the ubiquitin promoter. Data showed the production and dissemination of a high number of embryogenic calli in addition to obtaining plants transformed with the cry1Aa and cry1B genes until the reproductive phase. The feed bioassays with the transformed plants and Spodoptera frugiperda (JE Smith) larvae indicated high rates of mortality to the insect target. The highest corrected mortality rate achieved under laboratory conditions with Bt-rice plants transformed with the cry1B and cry1Aa genes was 94 and 84%, respectively. Thus, our results demonstrated the great potential of transformed Bt-rice plants in controlling the damage caused by these insect pests in rice paddy fields.

  3. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures.

    Science.gov (United States)

    Unbehend, Melanie; Hänniger, Sabine; Vásquez, Gissella M; Juárez, María Laura; Reisig, Dominic; McNeil, Jeremy N; Meagher, Robert L; Jenkins, David A; Heckel, David G; Groot, Astrid T

    2014-01-01

    The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this could have been due to inter-strain and/or geographic differences. Therefore, we investigated whether corn- and rice-strain males differed in their response to different synthetic pheromone blends in different regions in North America, the Caribbean and South America. All trapped males were strain-typed by two strain-specific mitochondrial DNA markers. In the first experiment, we found a nearly similar response of corn- and rice-strain males to two different 4-component blends, resembling the corn- and rice-strain female blend we previously described from females in Florida. This response showed some geographic variation in fields in Canada, North Carolina, Florida, Puerto Rico, and South America (Peru, Argentina). In dose-response experiments with the critical secondary sex pheromone component (Z)-7-dodecenyl acetate (Z7-12:OAc), we found some strain-specific differences in male attraction. While the response to Z7-12:OAc varied geographically in the corn-strain, rice-strain males showed almost no variation. We also found that the minor compound (Z)-11-hexadecenyl acetate (Z11-16:OAc) did not increase attraction of both strains in Florida and of corn-strain males in Peru. In a fourth experiment, where we added the stereo-isomer of the critical sex pheromone component, (E)-7-dodecenyl acetate, to the major pheromone component (Z)-9-tetradecenyl acetate (Z9-14:OAc), we found that this compound was attractive to males in North Carolina, but not to males in Peru. Overall, our results suggest that both strains show rather geographic than strain-specific differences in their response to pheromone lures, and that regional sexual communication differences might cause geographic

  4. Laboratory and field evaluations of the efficacy of a fast-killing baculovirus isolate from Spodoptera frugiperda.

    Science.gov (United States)

    Behle, Robert W; Popham, Holly J R

    2012-02-01

    Three biopesticide parameters were evaluated for a fast-killing isolate (3AP2) and a wild-type isolate (Sf3) of Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV). Both isolates were evaluated for virus production using in vivo methods, for speed of kill based on bioassay of applications to glasshouse-grown and field-grown plants, and for residual insecticidal activity of unformulated virus and an encapsulating formulation to provide UV protection. Two inoculation rates comparing relative in vivo production of the isolates demonstrated 3AP2 inoculated larvae were significantly smaller than Sf3 inoculated larvae at death. At the lower inoculation rate, Sf3 inoculated larvae produced approximately twofold more occlusion bodies as the 3AP2 inoculated larvae. A model system of applications to cabbage plants and a bioassay to observe mortality of neonate S. frugiperda (J.E. Smith) after feeding on samples of treated leaves was used to evaluate speed of kill and residual insecticidal activity. The LT(50) for the 3AP2 isolate was at least 30 h less than the LT(50) for the Sf3 isolate when applied to either glasshouse-grown or field-grown plants. The spray-dried lignin encapsulating formulation provided similar benefits to both virus isolates when exposed to simulated sunlight in the laboratory and to natural sunlight in the field. For treatment applications to field grown cabbage in June, the half-life for efficacy of unformulated virus was 26.7 h for encapsulated virus. These results demonstrate that improved technologies can be combined to address characteristics which otherwise can limit the commercial potential of microbial-based biological insecticides.

  5. Identification and RNA Interference of the Pheromone Biosynthesis Activating Neuropeptide (PBAN) in the Common Cutworm Moth Spodoptera litura (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Lu, Qin; Huang, Ling-Yan; Chen, Peng; Yu, Jin-Feng; Xu, Jin; Deng, Jian-Yu; Ye, Hui

    2015-06-01

    Spodoptera litura F. is one of the most destructive insect pests of many agricultural crops and notorious for developing insecticide resistance. Developing environmental friendly control methods such as novel pheromone and RNAi-related control strategies is imperative to control this pest. In the present study, the full-length cDNA encoding the diapause hormone and pheromone biosynthesis activating neuropeptide (DH-PBAN) was identified and characterized in S. litura. This 809-bp transcript contains a 573-nucleotide ORF encoding a 191-amino acid protein, from which five putative neuropeptides, including PBAN, DH, and α-, β-, and γ-subesophageal ganglion neuropeptides, were derived. Phylogenetic analysis showed that both the whole protein and each of the five neuropeptides have high similarities to those of DH-PBANs from other insect orders particularly Lepidoptera. Females treated with TKYFSPRLamide (the active core fragment of PBAN) produced significantly more four types of pheromone compounds (A; B; C; D) than controls. RNA interference by injection of PBAN dsRNA significantly reduced the relative expression levels of this gene in adult females (approximately reduced by 60%). As a consequence, females treated with PBAN dsRNA produced significantly less four types of pheromone compounds (A; B; C; D) than controls. These results suggest that PBAN function in activating sex pheromone biosynthesis and the RNAi of DH-PBAN gene can be induced by the injection of dsRNA into the body cavity in S. litura. This study suggests the possibility of novel pheromone-related pest control strategies based on RNAi techniques.

  6. The role of cytochrome c on apoptosis induced by Anagrapha falcifera multiple nuclear polyhedrosis virus in insect Spodoptera litura cells.

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    Kaiyu Liu

    Full Text Available There are conflicting reports on the role of cytochrome c during insect apoptosis. Our previous studies have showed that cytochrome c released from the mitochondria was an early event by western blot analysis and caspase-3 activation was closely related to cytochrome c release during apoptosis induced by baculovirus in Spodoptera litura cells (Sl-1 cell line. In the present study, alteration in mitochondrial morphology was observed by transmission electron microscopy, and cytochrome c release from mitochondria in apoptotic Sl-1 cells induced with Anagrapha falcifera multiple nuclear polyhedrosis virus (AfMNPV has further been confirmed by immunofluoresence staining protocol, suggesting that structural disruption of mitochondria and the release of cytochrome c are important events during Lepidoptera insect cell apoptosis. We also used Sl-1 cell-free extract system and the technique of RNA interference to further investigate the role of cytochrome c in apoptotic Sl-1 cells induced by AfMNPV. Caspase-3 activity in cell-free extracts supplemented with exogenous cytochrome c was determined and showed an increase with the extension of incubation time. DsRNA-mediated silencing of cytochrome c resulted in the inhibition of apoptosis and protected the cells from AfMNPV-induced cell death. Silencing of expression of cytochrome c had a remarkable effect on pro-caspase-3 and pro-caspase-9 activation and resulted in the reduction of caspase-3 and caspase-9 activity in Sl-1 cells undergoing apoptosis. Caspase-9 inhibitor could inhibit activation of pro-caspase-3, and the inhibition of the function of Apaf-1 with FSBA blocked apoptosis, hinting that Apaf-1 could be involved in Sl-1 cell apoptosis induced by AfMNPV. Taken together, these results strongly demonstrate that cytochrome c plays an important role in apoptotic signaling pathways in Lepidopteran insect cells.

  7. Degradation of pheromone and plant volatile components by a same odorant-degrading enzyme in the cotton leafworm, Spodoptera littoralis.

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    Nicolas Durand

    Full Text Available BACKGROUND: Odorant-Degrading Enzymes (ODEs are supposed to be involved in the signal inactivation step within the olfactory sensilla of insects by quickly removing odorant molecules from the vicinity of the olfactory receptors. Only three ODEs have been both identified at the molecular level and functionally characterized: two were specialized in the degradation of pheromone compounds and the last one was shown to degrade a plant odorant. METHODOLOGY: Previous work has shown that the antennae of the cotton leafworm Spodoptera littoralis, a worldwide pest of agricultural crops, express numerous candidate ODEs. We focused on an esterase overexpressed in males antennae, namely SlCXE7. We studied its expression patterns and tested its catalytic properties towards three odorants, i.e. the two female sex pheromone components and a green leaf volatile emitted by host plants. CONCLUSION: SlCXE7 expression was concomitant during development with male responsiveness to odorants and during adult scotophase with the period of male most active sexual behaviour. Furthermore, SlCXE7 transcription could be induced by male exposure to the main pheromone component, suggesting a role of Pheromone-Degrading Enzyme. Interestingly, recombinant SlCXE7 was able to efficiently hydrolyze the pheromone compounds but also the plant volatile, with a higher affinity for the pheromone than for the plant compound. In male antennae, SlCXE7 expression was associated with both long and short sensilla, tuned to sex pheromones or plant odours, respectively. Our results thus suggested that a same ODE could have a dual function depending of it sensillar localisation. Within the pheromone-sensitive sensilla, SlCXE7 may play a role in pheromone signal termination and in reduction of odorant background noise, whereas it could be involved in plant odorant inactivation within the short sensilla.

  8. Inheritance of Cry1F resistance, cross-resistance and frequency of resistant alleles in Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Vélez, A M; Spencer, T A; Alves, A P; Moellenbeck, D; Meagher, R L; Chirakkal, H; Siegfried, B D

    2013-12-01

    Transgenic maize, Zea maize L., expressing the Cry1F protein from Bacillus thuringiensis has been registered for Spodoptera frugiperda (J. E. Smith) control since 2003. Unexpected damage to Cry1F maize was reported in 2006 in Puerto Rico and Cry1F resistance in S. frugiperda was documented. The inheritance of Cry1F resistance was characterized in a S. frugiperda resistant strain originating from Puerto Rico, which displayed >289-fold resistance to purified Cry1F. Concentration-response bioassays of reciprocal crosses of resistant and susceptible parental populations indicated that resistance is recessive and autosomal. Bioassays of the backcross of the F1 generation crossed with the resistant parental strain suggest that a single locus is responsible for resistance. In addition, cross-resistance to Cry1Aa, Cry1Ab, Cry1Ac, Cry1Ba, Cry2Aa and Vip3Aa was assessed in the Cry1F-resistant strain. There was no significant cross-resistance to Cry1Aa, Cry1Ba and Cry2Aa, although only limited effects were observed in the susceptible strain. Vip3Aa was highly effective against susceptible and resistant insects indicating no cross-resistance with Cry1F. In contrast, low levels of cross-resistance were observed for both Cry1Ab and Cry1Ac. Because the resistance is recessive and conferred by a single locus, an F1 screening assay was used to measure the frequency of Cry1F-resistant alleles from populations of Florida and Texas in 2010 and 2011. A total frequency of resistant alleles of 0.13 and 0.02 was found for Florida and Texas populations, respectively, indicating resistant alleles could be found in US populations, although there have been no reports of reduced efficacy of Cry1F-expressing plants.

  9. INSECTICIDAL POTENTIALITY OF FLAVONOIDS FROM CELL SUSPENSION CULTURE OF MARCHANTIA LINEARIS LEHM. & LINDENB AGAINST SPODOPTERA LITURA F.

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    Remya Krishnan

    2015-05-01

    Full Text Available Bryophytes were diverse, primitive non vascular am phibious taxa distributed worldwide and form the second largest category of plants. Bryophytes synthesize an array of phytochemicals to combat against the unhospitable environmental conditions including predation, UV radiation, high temperature and pest and pathogens. The present investigation was undertaken to elucidate flavonoids from in vitro cell cultures of the liverwort Marchantia linearis Lehm. & Lindenb. its fractionation and analysis of insecticidal potentialities. Initially, callus culture was initiated from spores in MS/5 media containing gr owth regulators BAP and NAA at the concentration of 2 mg/L and 0.5 mg/L. Agitation of the friable callus at lowe r rpm bring about lower leve l of cell dispersion, on the contrary at higher rpm might have risk of cell collision that is why rpm was kept at moderate speed i.e., 110 rpm. Continuous sub culturing process substantially improves cell growth and biomass. In the second phase, the flavonoids were isolated from cell suspension cultures of M. linearis and were fractionated by TLC and HPLC PAD chromatogram, which revealed the presence of quer cetin, luteolin, apigenin , rutin and kaempferol. In vivo insecticidal analysis revealed significant antifeedan t, larvicidal and pupicidal activities at all the concentrations against 5 th instar larvae of Spodoptera litura . The extract also exhibited feeding deterrent activity with M. linearis. Similarly, the nutritional parameters were also affected i.e., reduced ECI (Efficiency of conversion of ingested food and ECD (Efficiency of conversion of digested food and increased AD (Approximate digestibility and metabolic cost for the larvae, when compared with the control. The consumption of the basal diet with the incorporation of flavonoids by S. litura larvae was not significantly different compared to the co nsumption of the control diet by the larvae. Faecal production reduced proportionally with

  10. Cytochrome P450s and cytochrome P450 reductase in the olfactory organ of the cotton leafworm Spodoptera littoralis.

    Science.gov (United States)

    Pottier, M-A; Bozzolan, F; Chertemps, T; Jacquin-Joly, E; Lalouette, L; Siaussat, D; Maïbèche-Coisne, M

    2012-12-01

    Cytochrome P450 enzymes (P450s) are involved in many physiological functions in insects, such as the metabolism of signal molecules, adaptation to host plants and insecticide resistance. Several P450s have been reported in the olfactory organs of insects, the antennae, and have been proposed to play a role in odorant processing and/or xenobiotic metabolism. Despite recent transcriptomic analyses in several species, the diversity of antennal P450s in insects has not yet been investigated. Here, we report the identification of 37 putative P450s expressed in the antennae of the pest moth Spodoptera littoralis, as well as the characterization of a redox partner, cytochrome P450 reductase (CPR). Phylogenetic analysis revealed that S. littoralis P450s belong to four clades defined by their conservation with vertebrate P450s and their cellular localization. Interestingly, the CYP3 and CYP4 clans, which have been described to be mainly involved in the metabolism of plant compounds and xenobiotics, were largely predominant. More surprisingly, two P450s related to ecdysteroid metabolism were also identified. Expression patterns in adult and larval tissues were studied. Eight P450s appeared to be specific to the chemosensory organs, ie the antennae and proboscis, suggesting a specific role in odorant and tastant processing. Moreover, exposure of males to a plant odorant down-regulated the transcript level of CPR, revealing for the first time the regulation of this gene by odorants within insect antennae. This work suggests that the antennae of insects are a key site for P450-mediated metabolism of a large range of exogenous and endogenous molecules.

  11. Effects of nickel exposure on testicular function, oxidative stress, and male reproductive dysfunction in Spodoptera litura Fabricius.

    Science.gov (United States)

    Sun, Hongxia; Wu, Wenjing; Guo, Jixing; Xiao, Rong; Jiang, Fengze; Zheng, Lingyan; Zhang, Guren

    2016-04-01

    Nickel is an environmental pollutant that adversely affects the male reproductive system. In the present study, the effects of nickel exposure on Spodoptera litura Fabricius were investigated by feeding larvae artificial diets containing different doses of nickel for three generations. Damage to testes and effects on male reproduction were examined. The amount of nickel that accumulated in the testes of newly emerged males increased as the nickel dose in the diet increased during a single generation. Nickel exposure increased the amount of thiobarbituric acid reactive substances and decreased the amount of glutathione in treatment groups compared with the control. The activity levels of the antioxidant response indices superoxide dismutases, catalase, and glutathione peroxidase in the testes showed variable dose-dependent relationships with nickel doses and duration of exposure. Nickel doses also disrupted the development of the testes by decreasing the weight and volume of testes and the number of eupyrene and apyrene sperm bundles in treatment groups compared with the control. When the nickel-treated males mated with normal females, fecundity was inhibited by the higher nickel doses in all three generations, but fecundity significantly increased during the second generation, which received 5 mg kg(-1) nickel. Hatching rates in all treatments significantly decreased in a dose-dependent manner in the three successive generations. The effects of nickel on these parameters correlated with the duration of nickel exposure. Results indicate assays of testes may be a novel and efficient means of evaluating the effects of heavy metals on phytophagous insects in an agricultural environment.

  12. Biopotency of serine protease inhibitors from cowpea (Vigna unguiculata) seeds on digestive proteases and the development of Spodoptera littoralis (Boisduval).

    Science.gov (United States)

    Abd El-latif, Ashraf Oukasha

    2015-05-01

    Serine protease inhibitors (PIs) have been described in many plant species and are universal throughout the plant kingdom, where trypsin inhibitors is the most common type. In the present study, trypsin and chymotrypsin inhibitory activity was detected in the seed flour extracts of 13 selected cultivars/accessions of cowpea. Two cowpea cultivars, Cream7 and Buff, were found to have higher trypsin and chymotrypsin inhibitory potential compared to other tested cultivars for which they have been selected for further purification studies using ammonium sulfate fractionation and DEAE-Sephadex A-25 column. Cream7-purified proteins showed two bands on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) corresponding to molecular mass of 17.10 and 14.90 kDa, while the purified protein from Buff cultivar showed a single band corresponding mass of 16.50 kDa. The purified inhibitors were stable at temperature below 60°C and were active at wide range of pH from 2 to 12. The kinetic analysis revealed noncompetitive type of inhibition for both inhibitors against both enzymes. The inhibitor constant (Ki ) values suggested high affinity between inhibitors and enzymes. Purified inhibitors were found to have deep and negative effects on the mean larval weight, larval mortality, pupation, and mean pupal weight of Spodoptera littoralis, where Buff PI was more effective than Cream7 PI. It may be concluded that cowpea PI gene(s) could be potential insect control protein for future studies in developing insect-resistant transgenic plants.

  13. Identification of a novel cytochrome P450 CYP321B1 gene from tobacco cutworm moth (Spodoptera litura) and RNA interference to evaluate its role in commonly used insecticides

    Science.gov (United States)

    BACKGROUND: Insect cytochrome P450 monooxygenases (CYPs or P450s) play an important role in detoxifying insecticides leading to resistance in insect populations. A polyphagous pest, Spodoptera litura (Lepidoptera, Noctuidae) has been shown to be resistant to a wide range of insecticides. In this stu...

  14. Functional response of Telenomus remus Nixon(Hymenoptera, Scelionidae to Spodoptera frugiperda (J. E. Smith (Lepidoptera, Noctuidae eggs: effect of female age

    Directory of Open Access Journals (Sweden)

    Tatiana R. Carneiro

    2010-01-01

    Full Text Available Functional response of Telenomus remus Nixon (Hymenoptera, Scelionidae to Spodoptera frugiperda (J. E. Smith (Lepidoptera, Noctuidae eggs: effect of female age. Functional response of 24-h and 48-h-old Telenomus remus adults was studied on Spodoptera frugiperda eggs. The study was carried out in climatic chamber regulated at 25 ± 1°C, 70 ± 10% RH and 12:12h (L: D. Females of T. remus were honey fed and individualized in glass vials along with 25, 50, 75, 100, 150, 200, 250 or 300 eggs of S. frugiperda for 24 h. Complete randomized design with ten replications was adopted. The parameters evaluated to construct the functional response curve were daily average parasitism, searching rate and oviposition time. It was observed that the higher the egg density, the higher the parasitism for 24-h and 48-h-old females although there was a tendency of parasitism stabilization at 150-egg density. The results showed a type II functional response curve for both 24-h and 48-h-old female.

  15. Bioactivity of a water extract of boldus (Peumus boldus Molina against Spodoptera frugiperda (J.E. Smith and Helicoverpa zea Boddie (Lepidoptera: Noctuidae

    Directory of Open Access Journals (Sweden)

    Gonzalo Silva

    2013-06-01

    Full Text Available The insecticidal properties of water-extract of Peumus boldus Molina and its effect on the development cycle and feeding habits of Spodoptera frugiperda J.E. Smith and Helicoverpa zea Boddie were evaluated under laboratory conditions in concentrations of 0.25, 0.5, 1.0, 2.0, 4.0, and 8.0% (w/w. Spodoptera frugiperda was the most susceptible with 75% mortality at 7 d at 8% P. boldus concentration, while H. zea had only 30% mortality. LC50 was 2.31 mL kg-1 for S. frugiperda and 16.05 mL kg¹ for H. zea. When the extract concentration increased in the diet, larval size and weight, percentage of pupation and number of adults decreased, and the time required to reach those states was greater. Neonate larvae fed primarily on the diet with the lower extract concentration and the control was preferred by more than 50% of larvae. Inhibition of feeding, growth, weight gain of 3rd instar larvae as well as new biomass production decreased with concentration of the extract.

  16. Desenvolvimento e mortalidade larval de Spodoptera frugiperda em folhas de milho tratadas com extrato aquoso de folhas de Azadirachta indica Larval development and mortality of Spodoptera frugiperda fed on corn leaves treated with aqueous extract from Azadirachta indica leaves

    Directory of Open Access Journals (Sweden)

    Paulo Afonso Viana

    2003-01-01

    Full Text Available Estudou-se o efeito do extrato aquoso de folhas de nim sobre o desenvolvimento e a mortalidade de lagartas recém-eclodidas de Spodoptera frugiperda. Para constatação do efeito de contato e de ingestão, as lagartas foram pulverizadas e as folhas de milho submersas no extrato (10 mg.mL-1 em laboratório e/ou pulverizadas no campo com um pulverizador de CO2. Partes de folhas de milho tratadas foram colocadas em copos plásticos para alimentar as lagartas e trocadas a cada dois dias. Adjuvantes foram adicionados ao extrato visando melhorar sua aderência às superfícies tratadas. Os parâmetros avaliados foram a mortalidade e o desenvolvimento larval. As folhas de milho submergidas e pulverizadas com o extrato causaram elevada mortalidade (100% e prejudicaram o desenvolvimento das lagartas sobreviventes. Na avaliação realizada 10 dias após a aplicação, o espalhante adesivo e o óleo de soja misturados ao extrato melhoraram a eficiência deste. A mortalidade das lagartas ocorreu três dias após a aplicação do extrato e a sua pulverização diretamente sobre o inseto não prejudicou o desenvolvimento larval. O extrato aquoso de nim mostrou-se com potencial para o controle de S. frugiperda.The effect of aqueous extracts from neem leaves and spraying adjuvants were evaluated on development and mortality of neonate S. frugiperda larvae. Corn leaves were dipped in the aqueous extract (10 mg.mL-1 in the laboratory and/or sprayed in the field with a CO2 sprayer and placed in plastic cup for larvae rearing. The treated corn leaves were replaced every other day. Corn leaves submerged and sprayed with the extract caused high larval mortality (100% and showed a negative effect on the larval development. The spreading agent and soybean oil mixed with neem extract improved larval mortality at the end of the 10-day period. The aqueous extract caused lethal effect on S. frugiperda larvae after three days of the application and sprayed directly on the

  17. Harmonia axyridis (Coleoptera: Coccinellidae) exhibits no preference between Bt and non-Bt maize fed Spodoptera frugiperda (Lepidoptera: Noctuidae).

    Science.gov (United States)

    Dutra, Carla C; Koch, Robert L; Burkness, Eric C; Meissle, Michael; Romeis, Joerg; Hutchison, William D; Fernandes, Marcos G

    2012-01-01

    A recent shift in managing insect resistance to genetically engineered (GE) maize consists of mixing non-GE seed with GE seed known as "refuge in a bag", which increases the likelihood of predators encountering both prey fed Bt and prey fed non-Bt maize. We therefore conducted laboratory choice-test feeding studies to determine if a predator, Harmonia axyridis, shows any preference between prey fed Bt and non-Bt maize leaves. The prey species was Spodoptera frugiperda, which were fed Bt maize (MON-810), expressing the single Cry1Ab protein, or non-Bt maize. The predators were third instar larvae and female adults of H. axyridis. Individual predators were offered Bt and non-Bt fed prey larvae that had fed for 24, 48 or 72 h. Ten and 15 larvae of each prey type were offered to third instar and adult predators, respectively. Observations of arenas were conducted at 1, 2, 3, 6, 15 and 24 h after the start of the experiment to determine the number and type of prey eaten by each individual predator. Prey larvae that fed on non-Bt leaves were significantly larger than larvae fed Bt leaves. Both predator stages had eaten nearly all the prey by the end of the experiment. However, in all combinations of predator stage and prey age, the number of each prey type consumed did not differ significantly. ELISA measurements confirmed the presence of Cry1Ab in leaf tissue (23-33 µg/g dry weight) and S. frugiperda (2.1-2.2 µg/g), while mean concentrations in H. axyridis were very low (0.01-0.2 µg/g). These results confirm the predatory status of H. axyridis on S. frugiperda and that both H. axyridis adults and larvae show no preference between prey types. The lack of preference between Bt-fed and non-Bt-fed prey should act in favor of insect resistance management strategies using mixtures of GE and non-GE maize seed.

  18. Geographic variation in sexual attraction of Spodoptera frugiperda corn- and rice-strain males to pheromone lures.

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    Melanie Unbehend

    Full Text Available The corn- and rice-strains of Spodoptera frugiperda exhibit several genetic and behavioral differences and appear to be undergoing ecological speciation in sympatry. Previous studies reported conflicting results when investigating male attraction to pheromone lures in different regions, but this could have been due to inter-strain and/or geographic differences. Therefore, we investigated whether corn- and rice-strain males differed in their response to different synthetic pheromone blends in different regions in North America, the Caribbean and South America. All trapped males were strain-typed by two strain-specific mitochondrial DNA markers. In the first experiment, we found a nearly similar response of corn- and rice-strain males to two different 4-component blends, resembling the corn- and rice-strain female blend we previously described from females in Florida. This response showed some geographic variation in fields in Canada, North Carolina, Florida, Puerto Rico, and South America (Peru, Argentina. In dose-response experiments with the critical secondary sex pheromone component (Z-7-dodecenyl acetate (Z7-12:OAc, we found some strain-specific differences in male attraction. While the response to Z7-12:OAc varied geographically in the corn-strain, rice-strain males showed almost no variation. We also found that the minor compound (Z-11-hexadecenyl acetate (Z11-16:OAc did not increase attraction of both strains in Florida and of corn-strain males in Peru. In a fourth experiment, where we added the stereo-isomer of the critical sex pheromone component, (E-7-dodecenyl acetate, to the major pheromone component (Z-9-tetradecenyl acetate (Z9-14:OAc, we found that this compound was attractive to males in North Carolina, but not to males in Peru. Overall, our results suggest that both strains show rather geographic than strain-specific differences in their response to pheromone lures, and that regional sexual communication differences might cause

  19. Stress-induced apoptosis in Spodoptera frugiperda (Sf9) cells: baculovirus p35 mitigates eIF2 alpha phosphorylation.

    Science.gov (United States)

    Aparna, Gunda; Bhuyan, Abani K; Sahdev, Sudhir; Hasnain, Seyed E; Kaufman, Randal J; Ramaiah, Kolluru V A

    2003-12-30

    Spodoptera frugiperda (Sf9) ovarian cells, natural hosts for baculovirus, are good model systems to study apoptosis and also heterologous gene expression. We report that uninfected Sf9 cells readily undergo apoptosis and show increased phosphorylation of the alpha subunit of eukaryotic initiation factor 2 (eIF2alpha) in the presence of agents such as UVB light, etoposide, high concentrations of cycloheximide, and EGTA. In contrast, tunicamycin, A23187, and low concentrations of cycloheximide promoted eIF2alpha phosphorylation in Sf9 cells but without apoptosis. These findings therefore suggest that increased eIF2alpha phosphorylation does not always necessarily lead to apoptosis, but it is a characteristic hallmark of stressed cells and also of cells undergoing apoptosis. Cell death induced by the above agents was abrogated by infection of Sf9 cells with wild-type (wt) AcNPV. In contrast, Sf9 cells when infected with vAcdelta35, a virus carrying deletion of the antiapoptotic p35 gene, showed increased apoptosis and enhanced eIF2alpha phosphorylation. Further, a recombinant wt virus vAcS51D expressing human S51D, a phosphomimetic form of eIF2alpha, induced apoptosis in UVB pretreated Sf9 cells. However, infection with vAcS51A expressing a nonphosphorylatable form (S51A) of human eIF2alpha partially reduced apoptosis. Consistent with these findings, it has been observed here that caspase activation has led to increased eIF2alpha phosphorylation, while caspase inhibition by z-VAD-fmk reduced eIF2alpha phosphorylation selectively in cells exposed to proapoptotic agents. These findings therefore suggest that the stress signaling pathway determines apoptosis, and caspase activation is a prerequisite for increased eIF2alpha phosphorylation in Sf9 cells undergoing apoptosis. The findings also reinforce the conclusion for the first time that the "pancaspase inhibitor" baculovirus p35 mitigates eIF2alpha phosphorylation.

  20. Control effects of Beet armyworm nuclear polyhedrosis virus·Bacillus thuringiensis against the rice stem borer%甜核·苏云菌对水稻二化螟的防效

    Institute of Scientific and Technical Information of China (English)

    彭丽年; 蒋凡; 徐翔; 黄新春

    2011-01-01

    为减少化学农药在稻田的使用,在四川新都进行了2种生物农药混配制剂--甜核·苏云菌防治水稻二化螟试验和示范.结果表明:采用PB-16手动喷雾器防治试验,甜核·苏云菌对水稻二化螟的枯心、白穗和虫伤株的防治效果分别为98.0%、99.56%和99.29%,采用东-18机动喷雾器喷雾示范,甜核·苏云菌对二化螟的枯心、白穗和虫伤株的防治效果分别为96.44%、97.83%和96.69%,效果良好,可以在大面积生产中推广应用.%To reduce chemical pesticide use in paddy fields, we tested the Beet armyworm nuclear polyhedrosis virus · Bacillus thuringiensis, a mixture of 2 bio-pesticides, for its effects on the rice stem borer in Xindu county.The results of field trials showed that, by using the PB-16 manual sprayer, its control efficacies to dead heart,dead head and infested plants were 98.0%, 99.56% and 99.29%, respectively; by using the Dong-18 machine sprayer, its control efficacies were 96.44%, 97.83% and 96.69%, respectively.The mixture can be extended for large-scale use in agricultural production.