Reciprocal hybridization between Helicoverpa armigera (Hubner) and H. assulta Guenee followed by back-crossing of the hybrids (F1) with H. armigera produced backcross (BC) lines consisting of fertile females and males...Reciprocal hybridization between Helicoverpa armigera (Hubner) and H. assulta Guenee followed by back-crossing of the hybrids (F1) with H. armigera produced backcross (BC) lines consisting of fertile females and males. The F1 of H. armigera female and H. assulta male had only male, no female sex. In this case Haldane’s rule applies, and therefore it is proved that the sex chromosomes of Helicoverpa species are of ZW type, and the female is the heterozygous sex. This hybrid also showed significant het-erosis with the heaviest pupal weight, and when it was back-crossed with H. armigera female, the sex ratio of the BC offspring was distorted as 1 : 4. The potential utilization of this hybrid in genetic controlling H. armigera was finally discussed.展开更多
Using the electro-physiological technique, the sensory mechanisms of maxillary sensilla styloconica to stimulants and deterrents were explored on two closely related species, the generalist Helicoverpa armigera and th...Using the electro-physiological technique, the sensory mechanisms of maxillary sensilla styloconica to stimulants and deterrents were explored on two closely related species, the generalist Helicoverpa armigera and the specialist H. assulta. The results showed that: (i) in both species, cells sensitive to sucrose and azadirachtin were mainly in the lateral sensillum styloconicum, and those to inositol were in the medial sensillum styloconicum; (ii) sensitivity of medial sensillum styloconicum in H. assulta to inositol was higher than that in H. armigera; (iii) among 6 tested deterrents, only azadirachtin evoked high impulse discharge from the lateral sensillum styloconicum in both insects; (iv) the deterrents could disturb stimulants evoking impulse discharge from maxillary sensilla styloconica of both species in different degrees: To sucrose evoking impulses on lateral sensillum styloconicum, for H. armigera capsaicin had a strong inhibition and gossypol had a weak inhibition, while for H. assulta tannic acid, gossypol, and tomatine all had strong inhibition except nicotine and capsaicin; to inositol evoking impulses on medial sensilum styloconicum, for H. armigera inhibition of tomatine was strong but that of gossypol was weak; and for H. assulta inhibition of gossypol was strong but that of nicotine was weak.展开更多
Cadherins belong to one of the families of animal glycoproteins responsible for cal-cium-dependent cell-cell adhesion.Recent literatures showed that the cadherin-like in midgut of several insects served as the recepto...Cadherins belong to one of the families of animal glycoproteins responsible for cal-cium-dependent cell-cell adhesion.Recent literatures showed that the cadherin-like in midgut of several insects served as the receptor of Bt toxin Cry1A and the variation of cadherin-like is re-lated to insect’s resistance to Cry1A.The full-length cDNA encoding cadherin-like of Helicoverpa armigera is cloned by degenerate PCR and RACE techniques and the gene was designated as BtR-harm,which is 5581 bp in full-length,encoding 1730 amino acid residues(BtR-harm was deposited in GenBank and the accession number is AF519180).Its predicted molecular weight and isoelectric point were 195.39 kDa and 4.23,respectively.The inferred amino acid sequence includes a signal sequence,11 cadherin repeats,a membrane-proximal region,a transmem-brane region and a cytoplasmic region.Sequence analysis indicated that the deduced protein sequence was most similar to the cadherin-like from Heliothis virescens with 84.2%identity and highly similar to three other lepidopteran cadherin from Bombyx mori,Manduca sexta and Pectinophora gossypiella,with the sequence identities of 60.3.6%,57.5%and 51.0%,respec-tively.The cDNA encoding cadherin gene was expressed successfully in E.coli and the recom-binant proteins can bind with Cry1Ac.Truncation analysis and binding experiment of BtR-harm revealed that the Cry1A binding region was a contiguous 244-amino acid sequence,which lo-cated between amino acid 1217 and 1461.Semi-quantitative RT-PCR analysis showed that BtR-harm was highly expressed in midgut of H.armigera,very low expressed in foregut and hindgut and was not expressed in other tissues.After H.armigera producing resistance to Cry1Ac,the expression quantity of BtR-harm significantly decreased in midgut of H.armigera.It is the first confirmation that BtR-harm can function as receptor of Cry1Ac in H.armigera and the binding region was located on a contiguous 244 amino acid sequence,suggesting that the de-crease of expression quantity of BtR-harm is one of th展开更多
Helicoverpa armigera adults display a conspicuous positive phototactic behavior to light stimuli, and are especially sensitive to ultraviolet （UV） light. The effects of UV-A （longwave） exposures on adult longevity...Helicoverpa armigera adults display a conspicuous positive phototactic behavior to light stimuli, and are especially sensitive to ultraviolet （UV） light. The effects of UV-A （longwave） exposures on adult longevity and reproduction in H. armigera were investigated, as well as the development of the Ft generation. Paired adults were exposed to UV-A for various time periods （0, 1, 5 and 9 h/day）, until the end of adult life. The results showed that adult longevity decreased with increasing exposure time for both sexes, and a significant decrease was observed after exposure for 5 and 9 h/day. Fecundity increased when adults were exposed for 1 and 5 h/day, and a significant difference was observed in the 5 h/day group. Oviposition rates of females in all treatments were significantly higher than in the control. Exposure to UV-A for longer periods （5 and 9 h/day） caused a decline in cumulative survival of F1 immature stages, but no significant differences were found in egg hatch, pupation and eclosion. The developmental periods of F1 larvae were significantly prolonged after exposure to UV-A for 5 and 9 h/day. UV-A radiation had no significant effects on F1 pupal period.展开更多
Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antenn...Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that some volatiles shouldmodify sex pheromone caused behavior and that some of them could possibly be used as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field.展开更多
Sublethal effects of chlorantraniliprole to Helicoverpa armigera （Hiibner） larvae were evaluated through exposure of third instar larvae to the insecticide incorporated into an artificial diet. When larvae were fed ...Sublethal effects of chlorantraniliprole to Helicoverpa armigera （Hiibner） larvae were evaluated through exposure of third instar larvae to the insecticide incorporated into an artificial diet. When larvae were fed on the insecticide-containing diet for 7 d, the LC10, LC20, LC40, and LC50values were 3.790, 7.977, 21.577, and 33.121 μg active ingredient L^-1, respectively. Chlorantraniliprole at sublethal concentrations significantly reduced the larval body mass, emergence ratio, adult longevity and egg hatching rate in both the parental and offspring generations. The pupation and copulation rate in the parental generation and the pupal mass in the offspring also strongly decreased. Reproduction was seriously disturbed in both the parental and offspring groups even when only one of the partners was exposed to chlorantraniliprole at larval stages. However, at the lowest concentration of exposure （LC^0）, offspring fecundity was strongly reduced only when both partners were exposed. The net reproductive rate （R0）, intrinsic rate of increase （rm）, and gross reproduction rate （GRR） at LC20, LC40 concentrations were significantly lower than that of the control. Post-exposure effects also included an extended larval developmental time and increased male proportion in both generations. The doubling time （Dt） at LC20, LC40 concentrations as well as gross reproduction rate （GRR） at LC10 concentration were also significantly increased. Chlorantraniliprole might have significant effects on H. armigera population dynamics even at sublethal concentrations on both parental and offspring generations.展开更多
The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera （Hübner）.The cDNA contains a 444 bp open reading frame,...The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera （Hübner）.The cDNA contains a 444 bp open reading frame,encoding a protein with 147 amino acids,namely HarmOBP5.HarmOBP5 was expressed in Escherichia coli and the recombinant protein was purified by affinity chromatography.SDS-PAGE and Western blot analysis demonstrated that the purified protein can be used for further investigation of its binding characteristics.Competitive binding assays with 113 odorant chemicals indicated that HarmOBP5 has strong affinity to some special plant volatiles,including （E）-β-farnesene,ethyl butyrate,ethyl heptanoate,and acetic acid 2-methylbutyl ester.Based on three-dimensional （3D） model of AaegOBP1 from Aedes aegypti,a 3D model of HarmOBP5 was predicted.The model revealed that some key binding residues in HarmOBP5 may play important roles in odorant perception of H.armigera.This study provides clues for better understanding physiological functions of OBPs in H.armigera and other insects.展开更多
Cotton bollworm (Helicoverpa armigera) is one of the most serious insect pests of cotton. Transgenic cotton expressing Cry toxins derived from a soil bacterium, Bacillus thuringiensis (Bt), has been produced to target...Cotton bollworm (Helicoverpa armigera) is one of the most serious insect pests of cotton. Transgenic cotton expressing Cry toxins derived from a soil bacterium, Bacillus thuringiensis (Bt), has been produced to target this pest. Bt cotton has been widely planted around the world, and this has resulted in efficient control of bollworm populations with reduced use of synthetic insecticides. However, evolution of resistance by this pest threatens the continued success of Bt cotton. To date, no field populations of bollworm have evolved significant levels of resistance; however, several laboratory-selected Cry-resistant strains of H. armigera have been obtained, which suggests that bollworm has the capacity to evolve resistance to Bt. The development of resistance to Bt is of great concern, and there is a vast body of research in this area aimed at ensuring the continued success of Bt cotton. Here, we review studies on the evolution of Bt resistance in H. armigera, focusing on the biochemical and molecular basis of Bt resistance. We also discuss resistance management strategies, and monitoring programs implemented in China, Australia, and India.展开更多
The brush border membrane vesicles (BBMVs) in midgut of Helicoverpa armigera weresuccessfully separated, and most of the Aminopeptidase N (APN) activities in BBMV werepreserved. The 3-[(3-chlor-amidopropyl) dimethylam...The brush border membrane vesicles (BBMVs) in midgut of Helicoverpa armigera weresuccessfully separated, and most of the Aminopeptidase N (APN) activities in BBMV werepreserved. The 3-[(3-chlor-amidopropyl) dimethylammonio]-1-propane-sulphonate (CHAPS)can enhance the dissolution of BBMV, and phosphatidylinositol-specific phosopholipase C(PI-PLC) can cleave the APN from midgut membrane. The APN was primarily purified usinga Mono-Q column. The results of immunoblotting showed that the 120 and 170kDa proteinsin the BBMV could bind Cry1Ac, and 120kDa APN was a glycosylphosphalidylinositol(GPI)-anchored protein. Two Bt-resistant strains (Bt-P, Bt-M) were obtained after beingselected for more than five years in laboratory using Bt insecticides and Bt transgeniccotton incorporated into diet separately. The resistance of Bt-P and Bt-M were 1083.3and 48.7 times that of susceptible strain. The genes encoding APN1 in midgut ofsusceptible and resistant H.armigera were cloned by PCR and RACE techniques. Theinferred amino acid sequences of APN1 possessed the common character of APN family ininsects. In comparison with APN1 in susceptible strain, three nucleotide mutations wereobserved in the APN1 of Bt-M strain and resulted in two amino acid replace in theputative protein sequences, and eight nucleotide mutations were observed in Bt-P strainand resulted in five amino acid replace.展开更多
Light traps are widely utilized to monitor and manage insect pest populations.In late 2018,the fall armyworm(FAW),Spodoptera frugiperda,invaded China through Yunnan Province representing a huge threat to grain product...Light traps are widely utilized to monitor and manage insect pest populations.In late 2018,the fall armyworm(FAW),Spodoptera frugiperda,invaded China through Yunnan Province representing a huge threat to grain production.To estimate the efficiency of light traps on FAW moths,we first identified the opsin genes from FAW by using the transcriptome.Phylogenetic analysis indicated that the four opsins of FAW were clustered with those of other Noctuidae species.The expressed levels of opsins in S.frugiperda were lower than in Helicoverpa armigera,suggesting a different phototactic response between the two species.Then,we determined the phototactic behavior of FAW using H.armigera as a control,which is widely monitored and managed using light traps in China.Our results indicated that the two moths species showed significantly different phototactic behavior and both female and male FAW displayed faster flight-to-light speed than H.armigera.This may be due to a faster flight capacity in FAW compared to H.armigera.However,the capture rate of both female and male of S.frugiperda was significantly lower than that of H.armigera,which was consistent with the expression levels of opsins.These results support the positive phototaxis of S.frugiperda moths and suggest light traps could be used for monitoring and managing the pests,but with a lower efficiency than H.armigera.展开更多
The effects of cyhalothrin on the transient outward potassium current in central neurons of Helicoverpa armigera were studied by using the patch clamp techniques. The results showed that before using cyhalothrin （10....The effects of cyhalothrin on the transient outward potassium current in central neurons of Helicoverpa armigera were studied by using the patch clamp techniques. The results showed that before using cyhalothrin （10.5 mmol/L）, activation potential was approximately -40 mV, after application of the drug, the activation potential shifted roughly 10 mV to the negative potential direction, so channels can be activated more easily. Before and after cyhalothrin application, the change of current amplitude was insignificant. The value of V1/2 and k of activation curves did not change significantly, however, the V1/2 of the inactivation curves changed significantly. Inactivation curves significantly shifted to a negative direction, so that inactivation of the channels was hastened. It is indicated that there may exit a primary way in which cyhalothrin provides neurotoxicity to the nervous system through the regulation of activation potentials and inactivation state of IA channels.展开更多
An Or83b-like receptor gene was cloned from antennae of Helicoverpa assulta（Guenée） by using reverse transcription polymerase chain reaction（RT-PCR） and rapid amplification of cDNA ends（RACE）.Sequence analy...An Or83b-like receptor gene was cloned from antennae of Helicoverpa assulta（Guenée） by using reverse transcription polymerase chain reaction（RT-PCR） and rapid amplification of cDNA ends（RACE）.Sequence analysis revealed that the transcript of the Or83b-like receptor gene from H.assulta consists of 1 946 nucleotides and the open reading frame（ORF） encodes a peptide of 473 amino acids with 7 putative transmembrane domains.Alignment analysis suggested that amino acid sequence of Or83b-like receptor from H.assulta shares high identity with other Or83b family receptors and this gene was hence named as HassOr83b.Tissues expression analysis showed that the HassOr83b transcript is clearly observed in the antennae,labial palps and proboscises,but not in bodies,wings and legs.The further development expression analysis suggested HassOr83b is also expressed in several preadult stages,including early-stage larvae,late-stage larvae and pupae,but not in embryos.Locked nucleic acid（LNA）-based in situ hybridization of antennal section indicated that HassOr83b is expressed in a very large number of antennal cells,which suggests that HassOr83b may play a special role in olfaction in H.assulta.展开更多
A chemosensory protein named HarmCSP5 in cotton bollworm Helicoverpa armigera （Hvbner） was obtained from antennal eDNA libraries and expressed in Escherichia coll. The real time quantitative PCR （RT-qPCR） results ...A chemosensory protein named HarmCSP5 in cotton bollworm Helicoverpa armigera （Hvbner） was obtained from antennal eDNA libraries and expressed in Escherichia coll. The real time quantitative PCR （RT-qPCR） results indicated that HarmCSP5 gene was mainly expressed in male and female antennae but also expressed in female legs and wings. Competitive binding assays were performed to test the binding affinity of recombinant HarmCSP5 to 60 odor molecules including some cotton volatiles. The resules showed that HarmCSP5 showed strong binding abilities to 4-ehtylbenzaldehyde and 3,4-dimethlbenz aldehyde, whereas methyl phenylacetate, 2-decanone, 1-pentanol, carvenol, isobomeol, nerolidol, 2- nonanone and ethyl heptanoate have relatively weak binding affinity. Moreover, the predicted 3D model of HarmCSP5 consists of six α-helices located among residues 33-38 （αl）, 40-48 （α2）, 62-72 （α3）, 80-96 （α4）, 98-108 （α5）, and 116-119 （α6）, two pairs of disulfide bridges Cys49-Cys55, Cys75-Cys78. The two amino acid residues, Ile94 and Trpl01, may play crucial roles in HarmCSP5 binding with ligands and need further study for confirmation.展开更多
Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin II was obtained using methods such as salting out and native-PAGE from the cells of X. n...Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin II was obtained using methods such as salting out and native-PAGE from the cells of X. nematophila HB310. The histopathology of toxin II on H. armigera larvae was studied by dissecting an olefin slice of the midgut. The symptoms showed that the histopathology of the H. armigera midgut was similar to that of other novel midgut-active toxins such as the δ-endotoxins from Bacillus thuringiensis, as well as Tca from Photorhabdus luminescens W14. The midgut tissues of H. armigera fourth-instar larvae began to transform after the oral intake of the toxin Ⅱ over 6 h. First, the anterior region of the peritrophic membrane （PM） began to degrade followed by the elongation of the columnar cells. The epithelium decomposed gradually, and the midgut tissues were either loose or disordered. The PM disappeared after 12 h but reappeared after 72 h following transient or sublethal exposure to the toxin Ⅱ. Toxin Ⅱ also directly destroyed in vitro PMs of H. armigera.展开更多
The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top cha...The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.展开更多
Here we use amplified fragment length polymorphism （AFLP） to assess genetic differentiation of Helicoverpa armigera and H. assulta. The results indicated that both species-specific fingerprints and cluster analysis ...Here we use amplified fragment length polymorphism （AFLP） to assess genetic differentiation of Helicoverpa armigera and H. assulta. The results indicated that both species-specific fingerprints and cluster analysis showed the ability of AFLP technique to discriminate the two sibling species; among a total 1963 AFLP markers amplified from nine primer combinations： 777 （39.6%） were H. armigera-specific, 602 （30.7%） were H. assulta- specific, and 584 （29.7%） were common bands. The mean number ofH. armigera-specific bands was significantly more than that of H. assulta-specific bands for nine primer combinations （P 〈 0.05）; the intraspecific distance of H. armigera and H. assulta was 0.123 0 and 0.110 7 respectively, and the interspecific distance was 0.178 3. In addition, the percentage of polymorphic loci and estimated average heterozygosity were used to estimate genetic diversity of the two species. This study therefore demonstrates that AFLP analysis is a sensitive and reliable technique to study genetic differentiation and genetic relationships between species and provides sufficient molecular markers for future linkage map conslruction, location and eventual cloning of genes involved in traits differentiation.展开更多
The effect of transgenic double genes, Cry1A + CpTI cotton and Cry1Ac toxinon the parasitoid, Campoketis chlorideae Uchida of cotton bollworm, Helicoverpa armigera (Huebner),was investigated in the laboratory. Helicov...The effect of transgenic double genes, Cry1A + CpTI cotton and Cry1Ac toxinon the parasitoid, Campoketis chlorideae Uchida of cotton bollworm, Helicoverpa armigera (Huebner),was investigated in the laboratory. Helicoverpa armigera larvae when in the first, second and thirdinstar could not survive if fed on transgenic cotton leaves. Consequently, C. chlorideae larvaecould not complete their development if parasitizing on such hosts. After H. armigera larvae werereared on transgenic or traditional cotton leaves for 12-48 hours, they were parasitized by C.chlorideae females. Parasitized larvae continued to feed on transgenic or traditional cotton for12-48 h. The present results showed that the body weight of larvae of the parasitoids weresignificantly reduced when parasitized hosts fed on transgenic cotton leaves compared to those fedon traditional cotton. Duration of egg and larvae stage were significantly prolonged, pupal andadult weight of C. chloridae was decreased when the host larvae fed on transgenic cotton leaveslonger than 48 h. The development duration of C. chlorideae pupae on the hosts fed on transgeniccotton leaves in each treatment was not significantly different from those of controls. Thelongevity of parasitoid females and males fed with a solution containing Cry1Ac toxin was notsignificantly different with that of the control.展开更多
Objective:To evaluate the antifeedant,insecticidal and growth inhibition activities of Solanum pseudocapsicum(S.pseudocapsicum)seed extracts against Spodoptera litura(S.litura)and Helicotverpa armigera(H.armigera).Met...Objective:To evaluate the antifeedant,insecticidal and growth inhibition activities of Solanum pseudocapsicum(S.pseudocapsicum)seed extracts against Spodoptera litura(S.litura)and Helicotverpa armigera(H.armigera).Methods:Hcxane,diethyl cther,dichloromethanc and ethyl acetate seed extracts were prepared and tested for autifeedant,insecticidal and growth inhibitory activities against fourth instar larvae of&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.展开更多
基金the National Natural Science Foundation of China (Grant No. 39670492) and the Chinese Academy of Sciences (Grant No. KSCX2-1-02).
文摘Reciprocal hybridization between Helicoverpa armigera (Hubner) and H. assulta Guenee followed by back-crossing of the hybrids (F1) with H. armigera produced backcross (BC) lines consisting of fertile females and males. The F1 of H. armigera female and H. assulta male had only male, no female sex. In this case Haldane’s rule applies, and therefore it is proved that the sex chromosomes of Helicoverpa species are of ZW type, and the female is the heterozygous sex. This hybrid also showed significant het-erosis with the heaviest pupal weight, and when it was back-crossed with H. armigera female, the sex ratio of the BC offspring was distorted as 1 : 4. The potential utilization of this hybrid in genetic controlling H. armigera was finally discussed.
文摘Using the electro-physiological technique, the sensory mechanisms of maxillary sensilla styloconica to stimulants and deterrents were explored on two closely related species, the generalist Helicoverpa armigera and the specialist H. assulta. The results showed that: (i) in both species, cells sensitive to sucrose and azadirachtin were mainly in the lateral sensillum styloconicum, and those to inositol were in the medial sensillum styloconicum; (ii) sensitivity of medial sensillum styloconicum in H. assulta to inositol was higher than that in H. armigera; (iii) among 6 tested deterrents, only azadirachtin evoked high impulse discharge from the lateral sensillum styloconicum in both insects; (iv) the deterrents could disturb stimulants evoking impulse discharge from maxillary sensilla styloconica of both species in different degrees: To sucrose evoking impulses on lateral sensillum styloconicum, for H. armigera capsaicin had a strong inhibition and gossypol had a weak inhibition, while for H. assulta tannic acid, gossypol, and tomatine all had strong inhibition except nicotine and capsaicin; to inositol evoking impulses on medial sensilum styloconicum, for H. armigera inhibition of tomatine was strong but that of gossypol was weak; and for H. assulta inhibition of gossypol was strong but that of nicotine was weak.
基金This work was supported by the Nati onal Natual Science F oundation of China(Grant No.30300233)Chinese Ministry of ScienceTechnology(Grant Nos.G2000016208&2001AA212271)
文摘Cadherins belong to one of the families of animal glycoproteins responsible for cal-cium-dependent cell-cell adhesion.Recent literatures showed that the cadherin-like in midgut of several insects served as the receptor of Bt toxin Cry1A and the variation of cadherin-like is re-lated to insect’s resistance to Cry1A.The full-length cDNA encoding cadherin-like of Helicoverpa armigera is cloned by degenerate PCR and RACE techniques and the gene was designated as BtR-harm,which is 5581 bp in full-length,encoding 1730 amino acid residues(BtR-harm was deposited in GenBank and the accession number is AF519180).Its predicted molecular weight and isoelectric point were 195.39 kDa and 4.23,respectively.The inferred amino acid sequence includes a signal sequence,11 cadherin repeats,a membrane-proximal region,a transmem-brane region and a cytoplasmic region.Sequence analysis indicated that the deduced protein sequence was most similar to the cadherin-like from Heliothis virescens with 84.2%identity and highly similar to three other lepidopteran cadherin from Bombyx mori,Manduca sexta and Pectinophora gossypiella,with the sequence identities of 60.3.6%,57.5%and 51.0%,respec-tively.The cDNA encoding cadherin gene was expressed successfully in E.coli and the recom-binant proteins can bind with Cry1Ac.Truncation analysis and binding experiment of BtR-harm revealed that the Cry1A binding region was a contiguous 244-amino acid sequence,which lo-cated between amino acid 1217 and 1461.Semi-quantitative RT-PCR analysis showed that BtR-harm was highly expressed in midgut of H.armigera,very low expressed in foregut and hindgut and was not expressed in other tissues.After H.armigera producing resistance to Cry1Ac,the expression quantity of BtR-harm significantly decreased in midgut of H.armigera.It is the first confirmation that BtR-harm can function as receptor of Cry1Ac in H.armigera and the binding region was located on a contiguous 244 amino acid sequence,suggesting that the de-crease of expression quantity of BtR-harm is one of th
基金Acknowledgments The research was supported by National Natural Science Foundation of China （No. 30871639）. We thank Dr. Q.Y. Huang for the helpful comments and suggestions on the manuscript, Ms. S. Xu and X. Yuan for assistance with experiments.
文摘Helicoverpa armigera adults display a conspicuous positive phototactic behavior to light stimuli, and are especially sensitive to ultraviolet （UV） light. The effects of UV-A （longwave） exposures on adult longevity and reproduction in H. armigera were investigated, as well as the development of the Ft generation. Paired adults were exposed to UV-A for various time periods （0, 1, 5 and 9 h/day）, until the end of adult life. The results showed that adult longevity decreased with increasing exposure time for both sexes, and a significant decrease was observed after exposure for 5 and 9 h/day. Fecundity increased when adults were exposed for 1 and 5 h/day, and a significant difference was observed in the 5 h/day group. Oviposition rates of females in all treatments were significantly higher than in the control. Exposure to UV-A for longer periods （5 and 9 h/day） caused a decline in cumulative survival of F1 immature stages, but no significant differences were found in egg hatch, pupation and eclosion. The developmental periods of F1 larvae were significantly prolonged after exposure to UV-A for 5 and 9 h/day. UV-A radiation had no significant effects on F1 pupal period.
文摘Electroantennogram (EAG) evaluation of selected compounds from wilted leaves of black poplar, Populus nigra, showed that phenyl acetaldehyde, methyl salicylate, (E)-2-hexenal elicited strong responses from male antennae of Helicoverpa armigera. When mixed with sex pheromone (Ph), some volatiles, e.g. phenyl acetaldehyde, benzyl alcohol, phenylethanol, methylsalicylate, linalool, benzaldehyde, (Z)-3-hexenol, (Z)-3-hexenylacetate, (Z)-6-nonenol, cineole, (E)-2-hexenal, and geraniol elicited stronger responses from male antennae than Ph alone. Wind tunnel bioassay demonstrated that various volatiles could either enhance or inhibit the effect of synthetic sex pheromone. (E)-2-hexenal, (Z)-3-hexenol and linalool in combination with Ph could not induce any male to land on source at all, whereas phenyl acetaldehyde, benzaldehyde, (Z)-6-nonenol and salicylaldehyde combined with Ph enhanced male response rates by 58.63%, 50.33%, 51.85% and 127.78%, respectively, compared to Ph alone. These results suggested that some volatiles shouldmodify sex pheromone caused behavior and that some of them could possibly be used as a tool for disrupting mating or for enhancing the effect of synthetic sex pheromone in the field.
基金supported by the National 863 Program of China(2012AA101502)the Special Fund for Agro-Scientific Research in the Public Interest, China (200903033)
文摘Sublethal effects of chlorantraniliprole to Helicoverpa armigera （Hiibner） larvae were evaluated through exposure of third instar larvae to the insecticide incorporated into an artificial diet. When larvae were fed on the insecticide-containing diet for 7 d, the LC10, LC20, LC40, and LC50values were 3.790, 7.977, 21.577, and 33.121 μg active ingredient L^-1, respectively. Chlorantraniliprole at sublethal concentrations significantly reduced the larval body mass, emergence ratio, adult longevity and egg hatching rate in both the parental and offspring generations. The pupation and copulation rate in the parental generation and the pupal mass in the offspring also strongly decreased. Reproduction was seriously disturbed in both the parental and offspring groups even when only one of the partners was exposed to chlorantraniliprole at larval stages. However, at the lowest concentration of exposure （LC^0）, offspring fecundity was strongly reduced only when both partners were exposed. The net reproductive rate （R0）, intrinsic rate of increase （rm）, and gross reproduction rate （GRR） at LC20, LC40 concentrations were significantly lower than that of the control. Post-exposure effects also included an extended larval developmental time and increased male proportion in both generations. The doubling time （Dt） at LC20, LC40 concentrations as well as gross reproduction rate （GRR） at LC10 concentration were also significantly increased. Chlorantraniliprole might have significant effects on H. armigera population dynamics even at sublethal concentrations on both parental and offspring generations.
基金supported by the National Basic Research Program of China(2012CB114104)the National Natural Science Foundation of China(30871640,31071694)+1 种基金the National High-Tech R&D Program of China(2008AA02Z307)the International Cooperation and Exchange Foundation of NSFC-RS of China(31111130203).
文摘The full-length sequence of the odorant binding protein 5 gene,HarmOBP5,was obtained from an antennae cDNA library of cotton bollworm,Helicoverpa armigera （Hübner）.The cDNA contains a 444 bp open reading frame,encoding a protein with 147 amino acids,namely HarmOBP5.HarmOBP5 was expressed in Escherichia coli and the recombinant protein was purified by affinity chromatography.SDS-PAGE and Western blot analysis demonstrated that the purified protein can be used for further investigation of its binding characteristics.Competitive binding assays with 113 odorant chemicals indicated that HarmOBP5 has strong affinity to some special plant volatiles,including （E）-β-farnesene,ethyl butyrate,ethyl heptanoate,and acetic acid 2-methylbutyl ester.Based on three-dimensional （3D） model of AaegOBP1 from Aedes aegypti,a 3D model of HarmOBP5 was predicted.The model revealed that some key binding residues in HarmOBP5 may play important roles in odorant perception of H.armigera.This study provides clues for better understanding physiological functions of OBPs in H.armigera and other insects.
基金supported by the National Key Basic Program (Grant No. 2007CB109204)the Key Project for Breeding Genetically Modified Organisms (Grant No. 2008ZX08012-004)
文摘Cotton bollworm (Helicoverpa armigera) is one of the most serious insect pests of cotton. Transgenic cotton expressing Cry toxins derived from a soil bacterium, Bacillus thuringiensis (Bt), has been produced to target this pest. Bt cotton has been widely planted around the world, and this has resulted in efficient control of bollworm populations with reduced use of synthetic insecticides. However, evolution of resistance by this pest threatens the continued success of Bt cotton. To date, no field populations of bollworm have evolved significant levels of resistance; however, several laboratory-selected Cry-resistant strains of H. armigera have been obtained, which suggests that bollworm has the capacity to evolve resistance to Bt. The development of resistance to Bt is of great concern, and there is a vast body of research in this area aimed at ensuring the continued success of Bt cotton. Here, we review studies on the evolution of Bt resistance in H. armigera, focusing on the biochemical and molecular basis of Bt resistance. We also discuss resistance management strategies, and monitoring programs implemented in China, Australia, and India.
基金Research was supported by the National Natural Science Fundation of China(30200182)973 Program of Ministry of Science and Techno1ogy,China(001CB109004).
文摘The brush border membrane vesicles (BBMVs) in midgut of Helicoverpa armigera weresuccessfully separated, and most of the Aminopeptidase N (APN) activities in BBMV werepreserved. The 3-[(3-chlor-amidopropyl) dimethylammonio]-1-propane-sulphonate (CHAPS)can enhance the dissolution of BBMV, and phosphatidylinositol-specific phosopholipase C(PI-PLC) can cleave the APN from midgut membrane. The APN was primarily purified usinga Mono-Q column. The results of immunoblotting showed that the 120 and 170kDa proteinsin the BBMV could bind Cry1Ac, and 120kDa APN was a glycosylphosphalidylinositol(GPI)-anchored protein. Two Bt-resistant strains (Bt-P, Bt-M) were obtained after beingselected for more than five years in laboratory using Bt insecticides and Bt transgeniccotton incorporated into diet separately. The resistance of Bt-P and Bt-M were 1083.3and 48.7 times that of susceptible strain. The genes encoding APN1 in midgut ofsusceptible and resistant H.armigera were cloned by PCR and RACE techniques. Theinferred amino acid sequences of APN1 possessed the common character of APN family ininsects. In comparison with APN1 in susceptible strain, three nucleotide mutations wereobserved in the APN1 of Bt-M strain and resulted in two amino acid replace in theputative protein sequences, and eight nucleotide mutations were observed in Bt-P strainand resulted in five amino acid replace.
基金supported by the National Key Research and Development Program of China(2017YFB0403905)the Central Public-interest Scientific Institution Basal Research Fund,China(Y2019YJ06)the Agricultural Science and Technology Innovation Program of China(ASTIP-TRIC04)。
文摘Light traps are widely utilized to monitor and manage insect pest populations.In late 2018,the fall armyworm(FAW),Spodoptera frugiperda,invaded China through Yunnan Province representing a huge threat to grain production.To estimate the efficiency of light traps on FAW moths,we first identified the opsin genes from FAW by using the transcriptome.Phylogenetic analysis indicated that the four opsins of FAW were clustered with those of other Noctuidae species.The expressed levels of opsins in S.frugiperda were lower than in Helicoverpa armigera,suggesting a different phototactic response between the two species.Then,we determined the phototactic behavior of FAW using H.armigera as a control,which is widely monitored and managed using light traps in China.Our results indicated that the two moths species showed significantly different phototactic behavior and both female and male FAW displayed faster flight-to-light speed than H.armigera.This may be due to a faster flight capacity in FAW compared to H.armigera.However,the capture rate of both female and male of S.frugiperda was significantly lower than that of H.armigera,which was consistent with the expression levels of opsins.These results support the positive phototaxis of S.frugiperda moths and suggest light traps could be used for monitoring and managing the pests,but with a lower efficiency than H.armigera.
文摘The effects of cyhalothrin on the transient outward potassium current in central neurons of Helicoverpa armigera were studied by using the patch clamp techniques. The results showed that before using cyhalothrin （10.5 mmol/L）, activation potential was approximately -40 mV, after application of the drug, the activation potential shifted roughly 10 mV to the negative potential direction, so channels can be activated more easily. Before and after cyhalothrin application, the change of current amplitude was insignificant. The value of V1/2 and k of activation curves did not change significantly, however, the V1/2 of the inactivation curves changed significantly. Inactivation curves significantly shifted to a negative direction, so that inactivation of the channels was hastened. It is indicated that there may exit a primary way in which cyhalothrin provides neurotoxicity to the nervous system through the regulation of activation potentials and inactivation state of IA channels.
基金supported by the Excellent Youth Foundation of Henan Province of China (074100510013)the Science and Technology Innovation Foundation of Henan Agricultural University of China (2007-CX-014)
文摘An Or83b-like receptor gene was cloned from antennae of Helicoverpa assulta（Guenée） by using reverse transcription polymerase chain reaction（RT-PCR） and rapid amplification of cDNA ends（RACE）.Sequence analysis revealed that the transcript of the Or83b-like receptor gene from H.assulta consists of 1 946 nucleotides and the open reading frame（ORF） encodes a peptide of 473 amino acids with 7 putative transmembrane domains.Alignment analysis suggested that amino acid sequence of Or83b-like receptor from H.assulta shares high identity with other Or83b family receptors and this gene was hence named as HassOr83b.Tissues expression analysis showed that the HassOr83b transcript is clearly observed in the antennae,labial palps and proboscises,but not in bodies,wings and legs.The further development expression analysis suggested HassOr83b is also expressed in several preadult stages,including early-stage larvae,late-stage larvae and pupae,but not in embryos.Locked nucleic acid（LNA）-based in situ hybridization of antennal section indicated that HassOr83b is expressed in a very large number of antennal cells,which suggests that HassOr83b may play a special role in olfaction in H.assulta.
基金supported by the National 973 Program of China (2012CB114104)the National Natural Science Foundation of China (31171858)
文摘A chemosensory protein named HarmCSP5 in cotton bollworm Helicoverpa armigera （Hvbner） was obtained from antennal eDNA libraries and expressed in Escherichia coll. The real time quantitative PCR （RT-qPCR） results indicated that HarmCSP5 gene was mainly expressed in male and female antennae but also expressed in female legs and wings. Competitive binding assays were performed to test the binding affinity of recombinant HarmCSP5 to 60 odor molecules including some cotton volatiles. The resules showed that HarmCSP5 showed strong binding abilities to 4-ehtylbenzaldehyde and 3,4-dimethlbenz aldehyde, whereas methyl phenylacetate, 2-decanone, 1-pentanol, carvenol, isobomeol, nerolidol, 2- nonanone and ethyl heptanoate have relatively weak binding affinity. Moreover, the predicted 3D model of HarmCSP5 consists of six α-helices located among residues 33-38 （αl）, 40-48 （α2）, 62-72 （α3）, 80-96 （α4）, 98-108 （α5）, and 116-119 （α6）, two pairs of disulfide bridges Cys49-Cys55, Cys75-Cys78. The two amino acid residues, Ile94 and Trpl01, may play crucial roles in HarmCSP5 binding with ligands and need further study for confirmation.
文摘Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin II was obtained using methods such as salting out and native-PAGE from the cells of X. nematophila HB310. The histopathology of toxin II on H. armigera larvae was studied by dissecting an olefin slice of the midgut. The symptoms showed that the histopathology of the H. armigera midgut was similar to that of other novel midgut-active toxins such as the δ-endotoxins from Bacillus thuringiensis, as well as Tca from Photorhabdus luminescens W14. The midgut tissues of H. armigera fourth-instar larvae began to transform after the oral intake of the toxin Ⅱ over 6 h. First, the anterior region of the peritrophic membrane （PM） began to degrade followed by the elongation of the columnar cells. The epithelium decomposed gradually, and the midgut tissues were either loose or disordered. The PM disappeared after 12 h but reappeared after 72 h following transient or sublethal exposure to the toxin Ⅱ. Toxin Ⅱ also directly destroyed in vitro PMs of H. armigera.
基金Project supported by the National Basic Research Program(973)of China(No.2006CB102002)the Pilot Project of Knowledge Innovation Program of Chinese Academy of Sciences(No.KSCX2-YW-N-006)National Natural Science Foundation of China(No.30571253,30621003)
文摘The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera （Htibner）, fed on cotton bolls grown under elevated CO2 （double-ambient vs. ambient） in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.
基金We thank Si-Ping Li for technical contributions to this study, Dr Shi-Liang Zhou （Institute of Botany, Chinese Academy of Sciences）, Jian-Cheng Shen and Qing-Bo Tang for data processing, and Li Feng for help in rearing insects. We are particularly grateful to Dr De-Xing Zhang for his constructive comments that greatly improved the manuscript. Also we appreciate thoughtful discussions with Professor Li-Huang Zhu （Institute of Genetics and Developmental Biology, Chinese Academy of Sciences）. This work was supported by the National Natural Science Foundation of China （Grant Nos. 30330100 and 30471148）.
文摘Here we use amplified fragment length polymorphism （AFLP） to assess genetic differentiation of Helicoverpa armigera and H. assulta. The results indicated that both species-specific fingerprints and cluster analysis showed the ability of AFLP technique to discriminate the two sibling species; among a total 1963 AFLP markers amplified from nine primer combinations： 777 （39.6%） were H. armigera-specific, 602 （30.7%） were H. assulta- specific, and 584 （29.7%） were common bands. The mean number ofH. armigera-specific bands was significantly more than that of H. assulta-specific bands for nine primer combinations （P 〈 0.05）; the intraspecific distance of H. armigera and H. assulta was 0.123 0 and 0.110 7 respectively, and the interspecific distance was 0.178 3. In addition, the percentage of polymorphic loci and estimated average heterozygosity were used to estimate genetic diversity of the two species. This study therefore demonstrates that AFLP analysis is a sensitive and reliable technique to study genetic differentiation and genetic relationships between species and provides sufficient molecular markers for future linkage map conslruction, location and eventual cloning of genes involved in traits differentiation.
文摘The effect of transgenic double genes, Cry1A + CpTI cotton and Cry1Ac toxinon the parasitoid, Campoketis chlorideae Uchida of cotton bollworm, Helicoverpa armigera (Huebner),was investigated in the laboratory. Helicoverpa armigera larvae when in the first, second and thirdinstar could not survive if fed on transgenic cotton leaves. Consequently, C. chlorideae larvaecould not complete their development if parasitizing on such hosts. After H. armigera larvae werereared on transgenic or traditional cotton leaves for 12-48 hours, they were parasitized by C.chlorideae females. Parasitized larvae continued to feed on transgenic or traditional cotton for12-48 h. The present results showed that the body weight of larvae of the parasitoids weresignificantly reduced when parasitized hosts fed on transgenic cotton leaves compared to those fedon traditional cotton. Duration of egg and larvae stage were significantly prolonged, pupal andadult weight of C. chloridae was decreased when the host larvae fed on transgenic cotton leaveslonger than 48 h. The development duration of C. chlorideae pupae on the hosts fed on transgeniccotton leaves in each treatment was not significantly different from those of controls. Thelongevity of parasitoid females and males fed with a solution containing Cry1Ac toxin was notsignificantly different with that of the control.
基金Supported by University Grant Commission(UGC)X plan(Grant No.UGC/TN/GAC-2008)
文摘Objective:To evaluate the antifeedant,insecticidal and growth inhibition activities of Solanum pseudocapsicum(S.pseudocapsicum)seed extracts against Spodoptera litura(S.litura)and Helicotverpa armigera(H.armigera).Methods:Hcxane,diethyl cther,dichloromethanc and ethyl acetate seed extracts were prepared and tested for autifeedant,insecticidal and growth inhibitory activities against fourth instar larvae of&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.
