[Objective] The aim of the research was to analyze the resistance of binary insect-resistant transgenic soybean to Heliothis viriplaca.[Method]In this experiment, resistance analysis of the stabilized binary insect-re...[Objective] The aim of the research was to analyze the resistance of binary insect-resistant transgenic soybean to Heliothis viriplaca.[Method]In this experiment, resistance analysis of the stabilized binary insect-resistant transgenic soybean to Heliothis viriplaca was conducted in lab and in field conditions.[Result] The results indicated that the leaves of insect-resistant transgenic soybeans T5-150 and T5-195 showed lighter damage than those of non-transgenic soybeans. Meanwhile, the Heliothis viriplaca larvae fed on leaves of these two transgenic soybeans were characterized by less leaf consumption, shortening survival day, slower development and less pupation.[Conclusion]It was concluded that insect-resistance of transgenic soybean to Heliothis viriplaca was increased dramatically and the research provided a reference for selecting binary insect-resistant transgenic soybean to Heliothis viriplaca.展开更多
No ascovirus isolated from China has been sequenced so far. Therefore, in this study, we aimed to sequence the genome of Heliothis virescens ascovirus 3h （HvAV-3h） using the 454 pyrosequencing technology. The genome...No ascovirus isolated from China has been sequenced so far. Therefore, in this study, we aimed to sequence the genome of Heliothis virescens ascovirus 3h （HvAV-3h） using the 454 pyrosequencing technology. The genome was found to be 190,519-bp long with a G＋C content of 45.5%. We also found that it encodes 185 hypothetical open reading frames （ORFs） along with at least 50 amino acids, including 181 ORFs found in other ascoviruses and 4 unique ORFs. Gene-parity plots and phylogenetic analysis revealed a close relationship between HvAV-3h and three other HvAV-3a strains and a distant relationship with Spodoptera frugiperda ascovirus la （SfAV-la）, Trichoplusia ni ascovirus 6a （TnAV-6a）, and Diadromus pulchellus ascovirus 4a （DpAV-4a）. Among the 185 potential genes encoded by the genome, 44 core genes were found in all the sequenced ascoviruses. In addition, 25 genes were found to be conserved in all ascoviruses except DpAV-4a. In the HvAV-3h genome, 24 baculovirus repeat ORFs （bros） were present, and the typical homologous repeat regions （hrs） were absent. This study supplies information important for understanding the conservation and functions of ascovirus genes as well as the variety of ascoviral genomes.展开更多
As specific pathogens of noctuid pests,including Spodoptera exigua,S.litura,Helicoverpa armigera,and Mythimna separata,ascoviruses are suitable for the development of bioinsecticides.In this study,the infectivity of H...As specific pathogens of noctuid pests,including Spodoptera exigua,S.litura,Helicoverpa armigera,and Mythimna separata,ascoviruses are suitable for the development of bioinsecticides.In this study,the infectivity of Heliothis virescens ascovirus 3j(HvAV-3j)on insect and mammalian cells was evaluated.HvAV-3j infection induced drastic morphological changes in Sf9,HzAMl,SeFB,and HaFB cells,including swelling and detachmen Notably,the latter phenomena did not occur in HvAV-3j-inoculated mammalian cells(HEK293,7402,HePG2,PK15,ST,and TM3).MTT assays indicated that HvAV-3j inhibited the growth of host insect cells from the 6th hpi,but no effects were detected in the HvAV-3j-inoculated mammalian cells.Furthermore,viral DNA replication,gene transcription,and protein expression were investigated,and the results consistently suggested that HvAV-3j viruses were not able to replicate their genomic DNA,transcribe,or express their proteins in the non-target vertebrate cells.The HvAV-3j genes were only transcribed and expressed in the four insect cell lines.These results indicated that HvAV-3j was infectious to cells derived from S.frugiperda,S.exigua,H.armigera,and H.zea but not to cells derived from human,pig,and mouse,suggesting that ascoviruses are safe to nontarget vertebrate cells.展开更多
3h-31 of Heliothis virescens ascovirus 3h(Hv AV-3h)is a highly conserved gene of ascoviruses.As an early gene of Hv AV-3h,3h-31 codes for a non-structural protein(3H-31)of Hv AV-3h.In the study,3h-31 was initially tra...3h-31 of Heliothis virescens ascovirus 3h(Hv AV-3h)is a highly conserved gene of ascoviruses.As an early gene of Hv AV-3h,3h-31 codes for a non-structural protein(3H-31)of Hv AV-3h.In the study,3h-31 was initially transcribed and expressed at 3 h post-infection(hpi)in the infected Spodoptera exigua fat body cells(Se FB).3h-31 was further inserted into the bacmid of Autographa californica nucleopolyhedrovirus(Ac MNPV)to generate an infectious baculovirus(Ac MNPV-31).In vivo experiments showed that budded virus production and viral DNA replication decreased with the expression of 3H-31,and lucent tubular structures were found around the virogenic stroma in the Ac MNPV-31-infected Se FB cells.In vivo,both LD50and LD90values of Ac MNPV-31 were significantly higher than those of the wild-type Ac MNPV(Ac MNPV-wt)in third instar S.exigua larvae.An interesting finding was that the liquefaction of the larvae killed by the infection of Ac MNPV-31 was delayed.Chitinase and cathepsin activities of Ac MNPV-31-infected larvae were significantly lower than those of Ac MNPV-wt-infected larvae.The possible regulatory function of the chitinase and cathepsin for 3H-31 was further confirmed by RNAi,which showed that larval cathepsin activity was significantly upregulated,but chitinase activity was not significantly changed due to the RNAi of 3h-31.Based on the obtained results,we assumed that the function of 3H-31 was associated with the inhibition of host larval chitinase and cathepsin activities,so as to restrain the hosts in their larval stages.展开更多
The cotton bollworm, Heliothis armigera (Hubner) is an important insect species at-tacking many crops. Their performances have been examined at temperatures from 15℃ to 35℃ and relative humidities (RH) between 22.5%...The cotton bollworm, Heliothis armigera (Hubner) is an important insect species at-tacking many crops. Their performances have been examined at temperatures from 15℃ to 35℃ and relative humidities (RH) between 22.5% and 100%, respectively, in order to assess possible effect of climate in future on its occurrence and infestation. Durations of all developmental stages of the insect shortened with increasing temperature. The temperature favoring population growth ranged from 25℃ to 30℃.Larval duration and adult longevity decreased as relative humidity increased, but development of other stages was independent of RH. At RH of over 64%, their survival rate, egg production and oviposition rate varied a little, and all the population parameters of the insect remained at a relative constant level.展开更多
Melanization is an important innate immune defense mechanism of insects,which can kill invading pathogens.Most pathogens,for their survival and reproduction,inhibit the melanization of the host.Interestingly,our resul...Melanization is an important innate immune defense mechanism of insects,which can kill invading pathogens.Most pathogens,for their survival and reproduction,inhibit the melanization of the host.Interestingly,our results suggested that after infection with Heliothis virescens ascovirus 3h(HvAV-3h),the speed of melanization in infected Spodoptera exigiia larval hemolymph was accelerated and that the phenoloxidase(PO)activity of hemolymph in larvae infected with HvAV-3h increased significantly(1.20-fold at 96 hpi,1.52-fold at 120 hpi,1.23-fold at 144 hpi,1.12-fold at 168 hpi).The transcription level of the gene encoding S.exigua prophenoloxidase-1(SePPO-1 gene)was upregulated dramatically in the fat body during the middle stage of infection.In addition,when melanization was inhibited or promoted,the replication of HvAV-3h was inhibited or promoted,respectively.In conclusion,infection with HvAV-3h can markedly induce melanization in the middle stage of infection,and melanization is helpful for HvAV-3h viral replication.展开更多
Multitoxin Bt-crops expressing insecticidal toxins with different modes of action, for example, Cry and Vip, are expected to improve resistance management in target pests. While Cry1A resistance has been relatively we...Multitoxin Bt-crops expressing insecticidal toxins with different modes of action, for example, Cry and Vip, are expected to improve resistance management in target pests. While Cry1A resistance has been relatively well characterized in some insect species, this is not the case for Vip3A, for which no mechanism of resistance has yet been identified. Here we applied HT-SuperSAGE to analyze the transcriptome of the gut tissue of tobacco budworm Heliothis virescens (F.) laboratory-selected for Vip3Aa resistance. From a total of 1 324 252 sequence reads, 5 895 126-bp tags were obtained representing 17 751 nonsingleton unique transcripts (UniTags) from genetically similar Vip3Aa-resistant (Vip- Sel) and susceptible control (Vip-Unsel) strains. Differential expression was significant (≥2.5 fold or ≤0.4;P < 0.05) for 1989 sequences (11.2% of total UniTags), where 420 represented overexpressed (OE) and 1569 underexpressed (UE) genes in Vip-Sel. BLASTN searches mapped 419 UniTags to H. virescens sequence contigs, of which, 416 (106 OE and 310 UE) were unambiguously annotated to proteins in NCBI nonredundant protein databases. Gene Ontology distributed 345 of annotated UniTags in 14 functional categories with metabolism (including serine-type hydrolases) and translation/ribosome biogenesis being the most prevalent. A UniTag homologous to a particular member of the REsponse to PAThogen (REPAT) family was found among most overexpressed, while UniTags related to the putative Vip3Aa-binding ribosomal protein S2 (RpS2) were underexpressed. qRT-PCR of a subset of UniTags validated the HT-SuperSAGE data. This study is the first providing lepidopteran gut transcriptome associated with Vip3Aa resistance and a foundation for future attempts to elucidate the resistance mechanism.展开更多
In the early 1970s, Riddiford and Williams found that removal of pupal corpora cardiaca prevented calling behaviour in the silkmoth Antheraea polyphemus and Hyalophora cecropia. However, the reinvestigation by Sasaki ...In the early 1970s, Riddiford and Williams found that removal of pupal corpora cardiaca prevented calling behaviour in the silkmoth Antheraea polyphemus and Hyalophora cecropia. However, the reinvestigation by Sasaki on these two insects could not confirm it. Hollander and Yin reported that section of circumoesopha-展开更多
[Objective] The aim was to explore the morphological characteristics of ovum from Spodoptera exigua and Heliothis assulta.[Method]The ultra morphological characteristics of ovum was observed with scanning electron mic...[Objective] The aim was to explore the morphological characteristics of ovum from Spodoptera exigua and Heliothis assulta.[Method]The ultra morphological characteristics of ovum was observed with scanning electron microscope（SEM）.[Result]The ova from S.exigua and H.assulta are all spheroid,the former has net line decoration on surface,with some aeropyle distributed on the net line decoration;the micropyle is located in the center of polar and has plum flower-like engraving;the surface of chorion of the latter has the parallel crowns through two polar.Between the parallel crown,the surface of chorion has the decorated trapezium line,all crowns of second polar zone have breast-tuber that distributes in parallel at the same latitude in line,and there is no aeropyle distributing on chorion.[Conclusion] The ultra morphological characteristics of the ova from two Noctuidae species showed significant difference to each other,which enriched ontogenesis data and also provided reference for the accurate identification of two kinds of ova.展开更多
利用硅胶柱色谱及薄层色谱等进行了分离纯化，并通过^1H—NMR、^13C—NMR、ESI—MS等波谱技术进行结构鉴定，对棉铃虫虫生真菌Paecilomyces heliothis（Charles）Brown et Smith的菌丝体的化学成分进行了研究．结果共分离得到10个化合...利用硅胶柱色谱及薄层色谱等进行了分离纯化，并通过^1H—NMR、^13C—NMR、ESI—MS等波谱技术进行结构鉴定，对棉铃虫虫生真菌Paecilomyces heliothis（Charles）Brown et Smith的菌丝体的化学成分进行了研究．结果共分离得到10个化合物。分别为时苯二甲酸二甲酯（1）、甘露醇（2）、十四碳酸（3）、麦角甾醇（4）、麦角甾-7，22-（E）二烯-3β．5α，6β-三醇（5）、过氧麦角甾醇（6）、尿嘧啶（7）、胸腺嘧啶（8）、丁二酸（9）、尿囊素（10）．化合物1～10均为首次从该菌种中分离得到．化合物1和10为首次从拟青霉属真菌中分离到。展开更多
Cotton (Gossypium hirsutum L.) produces a number of toxic terpenoid aldehyde (TA) compounds contained in epidermal glands that help protect the plant from pests and diseases. In the seed, one of these toxic compounds,...Cotton (Gossypium hirsutum L.) produces a number of toxic terpenoid aldehyde (TA) compounds contained in epidermal glands that help protect the plant from pests and diseases. In the seed, one of these toxic compounds, gossypol, limits the use of the seed to ruminants such as dairy cows. There are breeding techniques and germplasm available to decrease gossypol in the seed, but the breeding process also needs to include methods to evaluate the plant’s ability to resist insect pests. Three approaches were used to assess resistance of cotton to herbivory from bollworm (Helicoverpa zea Boddie) and tobacco budworm (Heliothis virescens F.) including field counts, controlled field antibiosis assays and laboratory feeding tests of young field grown leaves. Results indicated that both field and laboratory evaluation could provide an assessment of the cotton host’s resistance. Measurements of terpenoid aldehydes (TAs) in the seed and the leaves, confirmed that the levels and types of TAs in the seed were not always good estimators of leaf TAs and that other TAs such as hemigossypolone and heliocides contribute to host plant resistance.展开更多
ldentifying novel biocontrol agents and developing new strategies are urgent goals in insect pest biocontrol.Ascoviruses are potential competent insect viruses that may be developed into bioinsecticides,but this aim i...ldentifying novel biocontrol agents and developing new strategies are urgent goals in insect pest biocontrol.Ascoviruses are potential competent insect viruses that may be developed into bioinsecticides,but this aim is impeded by their poor oral infectivity.To improve the per os infectivity of ascovirus,Bacillus thuringiensis kurstaki(Btk)was employed as a helper to damage the midgut of lepidopteran larvae(Helicoverpa armigera,Mythimna separata,Spodoptera frugiperda,and S.litura)in formulations with Heliothis virescens ascovirus isolates(HvAV-3h and HvAV-3j).Btk and ascovirus mixtures(Btk/HvAV-3h and B1k/HvAV-3j)were fed to insect larvae(3rd instar).With the exception of S.frugiperda larvae,which exhibited low mortality after ingesting Btk,the larvae of the other tested species showed three types of response to feeding on the formulas:type I,the tested larvae(H.armigera)were killed by Btk infection so quickly that insufficient time and resources remained for ascoviral invasion;type II,both Btk and the ascovirus were depleted by their competition,such that neither was successfully released or colonized the tissue;type II,Btk was eliminated by the ascovirus,and the ascovirus achieved systemic infection in the tested larvae.The feeding of Btk/ascovirus formulas led to a great reduction in larval diet consumption and resulted in a significant decrease in the emergence rate of H.armigera,M.separata,and S.litura larvae,which suggested that the formulas exerted marked oral control effects on both the contemporary individuals and the next generation of these tested pest species.展开更多
Parasitoids use odor cues from infested plants and herbivore hosts to locate their hosts. Specialist parasitoids of generalist herbivores are predicted to rely more on herbivorederived cues than plant-derived cues. Mi...Parasitoids use odor cues from infested plants and herbivore hosts to locate their hosts. Specialist parasitoids of generalist herbivores are predicted to rely more on herbivorederived cues than plant-derived cues. Microplitis croceipes (Cresson)(Hymenoptera: Braconidae) is a relatively specialized larval endoparasitoid of Heliothis virescens (F.)(Lepidoptera: Noctuidae), which is a generalist herbivore on several crops including cotton and soybean. Using M. croceipes/H. virescens as a model system, we tested the following predictions about specialist parasitoids of generalist herbivores:(i) naive parasitoids will show innate responses to herbivore-emitted kairomones, regardless of host plant identity and (ii) herbivore-related experience will have a greater influence on intraspecific oviposition preference than plant-related experience. Inexperienced (naive) female M. croceipes did not discriminate between cotton-fed and soybean-fed H. virescens in oviposition choice tests, supporting our first prediction. Oviposition experience alone with either host group influenced subsequent oviposition preference while experience with infested plants alone did not elicit preference in M. croceipes, supporting our second prediction. Furthermore, associative learning of oviposition with host-damaged plants facilitated host location. I terestingly, naive parasitoids attacked more soybeathan cotton-fed host larvae in two-choice tests when a background of host-infested cotton odor was supplied, and vice versa. This suggests that plant volatiles may have created an olfactory contrast effect. We discussed ecological significance of the results and concluded that both plant- and herbivore-related experiences play important role in parasitoid host foraging.展开更多
A new putative transposon was identified in the tobacco budworm, Helio- this virescens. This transposon was characterized as a full length CORE-SINE （65 bp of ＂CORE＂ core specific nucleotide short interspersed elem...A new putative transposon was identified in the tobacco budworm, Helio- this virescens. This transposon was characterized as a full length CORE-SINE （65 bp of ＂CORE＂ core specific nucleotide short interspersed elements） that resembled sequences from three other lepidopterans and humans. In particular, the A-box and B-box regions of this sequence most closely conformed to the signature of CORE-SINEs from widely divergent species. This CORE-SINE was present as a polymorphism in a hypervariable region of the gene hscp, which is the target of pyrethroid insecticides and other xenobiotics in the nerve axon. We described this new putative transposon as Noct-1 due to its presence in a noctuid moth. This is the first description of a full-length CORE-SINE with the A-box, B-box, target site duplication, and candidate core domain from an insect.展开更多
文摘[Objective] The aim of the research was to analyze the resistance of binary insect-resistant transgenic soybean to Heliothis viriplaca.[Method]In this experiment, resistance analysis of the stabilized binary insect-resistant transgenic soybean to Heliothis viriplaca was conducted in lab and in field conditions.[Result] The results indicated that the leaves of insect-resistant transgenic soybeans T5-150 and T5-195 showed lighter damage than those of non-transgenic soybeans. Meanwhile, the Heliothis viriplaca larvae fed on leaves of these two transgenic soybeans were characterized by less leaf consumption, shortening survival day, slower development and less pupation.[Conclusion]It was concluded that insect-resistance of transgenic soybean to Heliothis viriplaca was increased dramatically and the research provided a reference for selecting binary insect-resistant transgenic soybean to Heliothis viriplaca.
基金supported partly by the National Natural Science Foundation of China (No. 31371995 and 31621061)the Strategic Priority Research Program of the Chinese Academy of Sciences (grant XDB11030400)+1 种基金STS Project of the Chinese Academy of Sciences (grant KFJ-SW-STS143-3)the Hunan Provincial Natural Science Foundation for Distinguished Young Scholar of China (14JJ1023)
文摘No ascovirus isolated from China has been sequenced so far. Therefore, in this study, we aimed to sequence the genome of Heliothis virescens ascovirus 3h （HvAV-3h） using the 454 pyrosequencing technology. The genome was found to be 190,519-bp long with a G＋C content of 45.5%. We also found that it encodes 185 hypothetical open reading frames （ORFs） along with at least 50 amino acids, including 181 ORFs found in other ascoviruses and 4 unique ORFs. Gene-parity plots and phylogenetic analysis revealed a close relationship between HvAV-3h and three other HvAV-3a strains and a distant relationship with Spodoptera frugiperda ascovirus la （SfAV-la）, Trichoplusia ni ascovirus 6a （TnAV-6a）, and Diadromus pulchellus ascovirus 4a （DpAV-4a）. Among the 185 potential genes encoded by the genome, 44 core genes were found in all the sequenced ascoviruses. In addition, 25 genes were found to be conserved in all ascoviruses except DpAV-4a. In the HvAV-3h genome, 24 baculovirus repeat ORFs （bros） were present, and the typical homologous repeat regions （hrs） were absent. This study supplies information important for understanding the conservation and functions of ascovirus genes as well as the variety of ascoviral genomes.
基金supported by the National Natural Science Foundation of China (31700141, 31872027)the grant of Chinese Post-doctoral special funding (2018T110832)Program to supporting research activities of female researchers in Ministry of education, culture, sports, science and technology-Japan
文摘As specific pathogens of noctuid pests,including Spodoptera exigua,S.litura,Helicoverpa armigera,and Mythimna separata,ascoviruses are suitable for the development of bioinsecticides.In this study,the infectivity of Heliothis virescens ascovirus 3j(HvAV-3j)on insect and mammalian cells was evaluated.HvAV-3j infection induced drastic morphological changes in Sf9,HzAMl,SeFB,and HaFB cells,including swelling and detachmen Notably,the latter phenomena did not occur in HvAV-3j-inoculated mammalian cells(HEK293,7402,HePG2,PK15,ST,and TM3).MTT assays indicated that HvAV-3j inhibited the growth of host insect cells from the 6th hpi,but no effects were detected in the HvAV-3j-inoculated mammalian cells.Furthermore,viral DNA replication,gene transcription,and protein expression were investigated,and the results consistently suggested that HvAV-3j viruses were not able to replicate their genomic DNA,transcribe,or express their proteins in the non-target vertebrate cells.The HvAV-3j genes were only transcribed and expressed in the four insect cell lines.These results indicated that HvAV-3j was infectious to cells derived from S.frugiperda,S.exigua,H.armigera,and H.zea but not to cells derived from human,pig,and mouse,suggesting that ascoviruses are safe to nontarget vertebrate cells.
基金supported by the National Natural Science Foundation of China(32070168,31700141,31872027)Provincial Natural Science Foundation of Hunan(2019JJ50234)+2 种基金Changsha Science and Technology Project(kq1901033)Double first-class construction project of Hunan Agricultural UniversitySakura Science Plan of Japan Science Technology Agency(JST)。
文摘3h-31 of Heliothis virescens ascovirus 3h(Hv AV-3h)is a highly conserved gene of ascoviruses.As an early gene of Hv AV-3h,3h-31 codes for a non-structural protein(3H-31)of Hv AV-3h.In the study,3h-31 was initially transcribed and expressed at 3 h post-infection(hpi)in the infected Spodoptera exigua fat body cells(Se FB).3h-31 was further inserted into the bacmid of Autographa californica nucleopolyhedrovirus(Ac MNPV)to generate an infectious baculovirus(Ac MNPV-31).In vivo experiments showed that budded virus production and viral DNA replication decreased with the expression of 3H-31,and lucent tubular structures were found around the virogenic stroma in the Ac MNPV-31-infected Se FB cells.In vivo,both LD50and LD90values of Ac MNPV-31 were significantly higher than those of the wild-type Ac MNPV(Ac MNPV-wt)in third instar S.exigua larvae.An interesting finding was that the liquefaction of the larvae killed by the infection of Ac MNPV-31 was delayed.Chitinase and cathepsin activities of Ac MNPV-31-infected larvae were significantly lower than those of Ac MNPV-wt-infected larvae.The possible regulatory function of the chitinase and cathepsin for 3H-31 was further confirmed by RNAi,which showed that larval cathepsin activity was significantly upregulated,but chitinase activity was not significantly changed due to the RNAi of 3h-31.Based on the obtained results,we assumed that the function of 3H-31 was associated with the inhibition of host larval chitinase and cathepsin activities,so as to restrain the hosts in their larval stages.
文摘The cotton bollworm, Heliothis armigera (Hubner) is an important insect species at-tacking many crops. Their performances have been examined at temperatures from 15℃ to 35℃ and relative humidities (RH) between 22.5% and 100%, respectively, in order to assess possible effect of climate in future on its occurrence and infestation. Durations of all developmental stages of the insect shortened with increasing temperature. The temperature favoring population growth ranged from 25℃ to 30℃.Larval duration and adult longevity decreased as relative humidity increased, but development of other stages was independent of RH. At RH of over 64%, their survival rate, egg production and oviposition rate varied a little, and all the population parameters of the insect remained at a relative constant level.
基金We would like to thank the American Journal Experts teamfor editing and revising the English language.This work was supported by the National Natural Science Foundation of China(31872027)Changsha Science and Technology Project(kq 1901033),and Double first-class construction project of Hunan Agricultural University.
文摘Melanization is an important innate immune defense mechanism of insects,which can kill invading pathogens.Most pathogens,for their survival and reproduction,inhibit the melanization of the host.Interestingly,our results suggested that after infection with Heliothis virescens ascovirus 3h(HvAV-3h),the speed of melanization in infected Spodoptera exigiia larval hemolymph was accelerated and that the phenoloxidase(PO)activity of hemolymph in larvae infected with HvAV-3h increased significantly(1.20-fold at 96 hpi,1.52-fold at 120 hpi,1.23-fold at 144 hpi,1.12-fold at 168 hpi).The transcription level of the gene encoding S.exigua prophenoloxidase-1(SePPO-1 gene)was upregulated dramatically in the fat body during the middle stage of infection.In addition,when melanization was inhibited or promoted,the replication of HvAV-3h was inhibited or promoted,respectively.In conclusion,infection with HvAV-3h can markedly induce melanization in the middle stage of infection,and melanization is helpful for HvAV-3h viral replication.
文摘Multitoxin Bt-crops expressing insecticidal toxins with different modes of action, for example, Cry and Vip, are expected to improve resistance management in target pests. While Cry1A resistance has been relatively well characterized in some insect species, this is not the case for Vip3A, for which no mechanism of resistance has yet been identified. Here we applied HT-SuperSAGE to analyze the transcriptome of the gut tissue of tobacco budworm Heliothis virescens (F.) laboratory-selected for Vip3Aa resistance. From a total of 1 324 252 sequence reads, 5 895 126-bp tags were obtained representing 17 751 nonsingleton unique transcripts (UniTags) from genetically similar Vip3Aa-resistant (Vip- Sel) and susceptible control (Vip-Unsel) strains. Differential expression was significant (≥2.5 fold or ≤0.4;P < 0.05) for 1989 sequences (11.2% of total UniTags), where 420 represented overexpressed (OE) and 1569 underexpressed (UE) genes in Vip-Sel. BLASTN searches mapped 419 UniTags to H. virescens sequence contigs, of which, 416 (106 OE and 310 UE) were unambiguously annotated to proteins in NCBI nonredundant protein databases. Gene Ontology distributed 345 of annotated UniTags in 14 functional categories with metabolism (including serine-type hydrolases) and translation/ribosome biogenesis being the most prevalent. A UniTag homologous to a particular member of the REsponse to PAThogen (REPAT) family was found among most overexpressed, while UniTags related to the putative Vip3Aa-binding ribosomal protein S2 (RpS2) were underexpressed. qRT-PCR of a subset of UniTags validated the HT-SuperSAGE data. This study is the first providing lepidopteran gut transcriptome associated with Vip3Aa resistance and a foundation for future attempts to elucidate the resistance mechanism.
文摘In the early 1970s, Riddiford and Williams found that removal of pupal corpora cardiaca prevented calling behaviour in the silkmoth Antheraea polyphemus and Hyalophora cecropia. However, the reinvestigation by Sasaki on these two insects could not confirm it. Hollander and Yin reported that section of circumoesopha-
基金Supported by National Trades(Agriculture)Scientific Research Special Foundation(200803007)~~
文摘[Objective] The aim was to explore the morphological characteristics of ovum from Spodoptera exigua and Heliothis assulta.[Method]The ultra morphological characteristics of ovum was observed with scanning electron microscope（SEM）.[Result]The ova from S.exigua and H.assulta are all spheroid,the former has net line decoration on surface,with some aeropyle distributed on the net line decoration;the micropyle is located in the center of polar and has plum flower-like engraving;the surface of chorion of the latter has the parallel crowns through two polar.Between the parallel crown,the surface of chorion has the decorated trapezium line,all crowns of second polar zone have breast-tuber that distributes in parallel at the same latitude in line,and there is no aeropyle distributing on chorion.[Conclusion] The ultra morphological characteristics of the ova from two Noctuidae species showed significant difference to each other,which enriched ontogenesis data and also provided reference for the accurate identification of two kinds of ova.
文摘利用硅胶柱色谱及薄层色谱等进行了分离纯化，并通过^1H—NMR、^13C—NMR、ESI—MS等波谱技术进行结构鉴定，对棉铃虫虫生真菌Paecilomyces heliothis（Charles）Brown et Smith的菌丝体的化学成分进行了研究．结果共分离得到10个化合物。分别为时苯二甲酸二甲酯（1）、甘露醇（2）、十四碳酸（3）、麦角甾醇（4）、麦角甾-7，22-（E）二烯-3β．5α，6β-三醇（5）、过氧麦角甾醇（6）、尿嘧啶（7）、胸腺嘧啶（8）、丁二酸（9）、尿囊素（10）．化合物1～10均为首次从该菌种中分离得到．化合物1和10为首次从拟青霉属真菌中分离到。
文摘Cotton (Gossypium hirsutum L.) produces a number of toxic terpenoid aldehyde (TA) compounds contained in epidermal glands that help protect the plant from pests and diseases. In the seed, one of these toxic compounds, gossypol, limits the use of the seed to ruminants such as dairy cows. There are breeding techniques and germplasm available to decrease gossypol in the seed, but the breeding process also needs to include methods to evaluate the plant’s ability to resist insect pests. Three approaches were used to assess resistance of cotton to herbivory from bollworm (Helicoverpa zea Boddie) and tobacco budworm (Heliothis virescens F.) including field counts, controlled field antibiosis assays and laboratory feeding tests of young field grown leaves. Results indicated that both field and laboratory evaluation could provide an assessment of the cotton host’s resistance. Measurements of terpenoid aldehydes (TAs) in the seed and the leaves, confirmed that the levels and types of TAs in the seed were not always good estimators of leaf TAs and that other TAs such as hemigossypolone and heliocides contribute to host plant resistance.
基金the National Natural Science Foundation of China(31700141,31872027)Provincial Natural Science Foundation of Hunan(2019JJ50234)+1 种基金Changsha Science and Technology Project(kq 1901033)Double firstclass construction project of Hunan Agricultural University.
文摘ldentifying novel biocontrol agents and developing new strategies are urgent goals in insect pest biocontrol.Ascoviruses are potential competent insect viruses that may be developed into bioinsecticides,but this aim is impeded by their poor oral infectivity.To improve the per os infectivity of ascovirus,Bacillus thuringiensis kurstaki(Btk)was employed as a helper to damage the midgut of lepidopteran larvae(Helicoverpa armigera,Mythimna separata,Spodoptera frugiperda,and S.litura)in formulations with Heliothis virescens ascovirus isolates(HvAV-3h and HvAV-3j).Btk and ascovirus mixtures(Btk/HvAV-3h and B1k/HvAV-3j)were fed to insect larvae(3rd instar).With the exception of S.frugiperda larvae,which exhibited low mortality after ingesting Btk,the larvae of the other tested species showed three types of response to feeding on the formulas:type I,the tested larvae(H.armigera)were killed by Btk infection so quickly that insufficient time and resources remained for ascoviral invasion;type II,both Btk and the ascovirus were depleted by their competition,such that neither was successfully released or colonized the tissue;type II,Btk was eliminated by the ascovirus,and the ascovirus achieved systemic infection in the tested larvae.The feeding of Btk/ascovirus formulas led to a great reduction in larval diet consumption and resulted in a significant decrease in the emergence rate of H.armigera,M.separata,and S.litura larvae,which suggested that the formulas exerted marked oral control effects on both the contemporary individuals and the next generation of these tested pest species.
文摘Parasitoids use odor cues from infested plants and herbivore hosts to locate their hosts. Specialist parasitoids of generalist herbivores are predicted to rely more on herbivorederived cues than plant-derived cues. Microplitis croceipes (Cresson)(Hymenoptera: Braconidae) is a relatively specialized larval endoparasitoid of Heliothis virescens (F.)(Lepidoptera: Noctuidae), which is a generalist herbivore on several crops including cotton and soybean. Using M. croceipes/H. virescens as a model system, we tested the following predictions about specialist parasitoids of generalist herbivores:(i) naive parasitoids will show innate responses to herbivore-emitted kairomones, regardless of host plant identity and (ii) herbivore-related experience will have a greater influence on intraspecific oviposition preference than plant-related experience. Inexperienced (naive) female M. croceipes did not discriminate between cotton-fed and soybean-fed H. virescens in oviposition choice tests, supporting our first prediction. Oviposition experience alone with either host group influenced subsequent oviposition preference while experience with infested plants alone did not elicit preference in M. croceipes, supporting our second prediction. Furthermore, associative learning of oviposition with host-damaged plants facilitated host location. I terestingly, naive parasitoids attacked more soybeathan cotton-fed host larvae in two-choice tests when a background of host-infested cotton odor was supplied, and vice versa. This suggests that plant volatiles may have created an olfactory contrast effect. We discussed ecological significance of the results and concluded that both plant- and herbivore-related experiences play important role in parasitoid host foraging.
文摘A new putative transposon was identified in the tobacco budworm, Helio- this virescens. This transposon was characterized as a full length CORE-SINE （65 bp of ＂CORE＂ core specific nucleotide short interspersed elements） that resembled sequences from three other lepidopterans and humans. In particular, the A-box and B-box regions of this sequence most closely conformed to the signature of CORE-SINEs from widely divergent species. This CORE-SINE was present as a polymorphism in a hypervariable region of the gene hscp, which is the target of pyrethroid insecticides and other xenobiotics in the nerve axon. We described this new putative transposon as Noct-1 due to its presence in a noctuid moth. This is the first description of a full-length CORE-SINE with the A-box, B-box, target site duplication, and candidate core domain from an insect.
