Spodoptera frugiperda multiple nucleopolyhedrovirus(SfMNPV),belonging to the species Alphabaculovirus spofrugiperdae,has been recently registered as an insecticide in China.This virus has a specific effect on the glob...Spodoptera frugiperda multiple nucleopolyhedrovirus(SfMNPV),belonging to the species Alphabaculovirus spofrugiperdae,has been recently registered as an insecticide in China.This virus has a specific effect on the global major agricultural pest Spodoptera frugiperda.To gain insights into viral infection,replication processes,and the complex formation of viral particles,in vitro studies using cell lines are essential tools.Although the IPLB-Sf9 and IPLB-Sf21 cell lines derived from S.frugiperda are widely used for studies on the infection and replication mechanisms of Autographa californica multiple nucleopolyhedrovirus(AcMNPV),their capacity to produce viral polyhedra after SfMNPV infection is not optimal.To address this limitation,a novel cell line named IOZCAS-Sf-1 was developed from a S.frugiperda population in Yunnan,China.The mitochondrial COX1 gene analysis confirmed the species origin of the IOZCAS-Sf-1 cell line.Furthermore,a comparative study was carried out to contrast the COX1 gene sequence of this novel cell line with that of IPLB-Sf9,highlighting the distinctions between the two.Importantly,the IOZCAS-Sf-1 cells exhibited a remarkable ability to generate polyhedra when infected with AcMNPV and SfMNPV,respectively.Consequently,this cellular lineage is considered a promising and valuable resource.It serves not only to investigate the molecular mechanisms of viral replication and its impact on host cells,but also to explore the transfection efficiency of SfMNPV DNA.This exploration further expands into its potential application in recombinant DNA experiments,laying a theoretical groundwork for the advancement of more effective biopesticides and sustainable agricultural practices.展开更多
Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities.Transient receptor potential(TRP)channels,which constitute a vast ion chann...Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities.Transient receptor potential(TRP)channels,which constitute a vast ion channel family,play pivotal roles in sensing the external environment and maintaining internal homeostasis in insects.TRP channels have been widely investigated for their critical roles in regulating various insect behaviors in recent years.In this study,we identified 15 TRP gene loci encoding 26 transcripts in the genome of S.frugiperda and analyzed their expression profiles at different developmental stages.The results revealed that S.frugiperda possesses four TRPC genes,six TRPA genes,one TRPM gene,two TRPV genes,one TRPN gene,and one TRPML gene,while a canonical TRPP is absent.Moreover,the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression system.The results showed that SfruTRPA1 is activated by temperature increases from 20 to 45℃,and there is no significant desensitization after repeated stimuli within the same temperature range.Additionally,SfruTRPA1 is activated by certain natural chemicals,including allyl isothiocyanate(AITC)and cinnamaldehyde(CA).These findings provide valuable insights to the TRP genes in S.frugiperda.展开更多
Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic ...Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic losses in agriculture.Pyemotes zhonghuajia,a newly identified mite parasitoid,has shown potential for controlling various agricultural insect pests.Therefore,this study tested the performance of P.zhonghuajia in parasitising S.frugiperda.We also investigated the sublethal effects of parasitism by P.zhonghuajia on host fitness traits,transgenerational impacts,and cellular and humoral immunity.Our result showed that the fifth-instar larvae of S.frugiperda parasitised by 40 P.zhonghuajia were all dead(i.e.,a lethal effect),while parasitism by 5 or 10 P.zhonghuajia was considered sublethal since many S.frugiperda survived to adulthood and produced offspring after mating.The sublethal influences from parasitism by P.zhonghuajia resulted in reduced pupal weight,adult emergence rate and fecundity,but increased developmental time and longevity.Parasitism at both lethal(40 mites)and sublethal(10 mites)levels impaired the cellular and humoral immunity of S.frugiperda.This study presents the first empirical evidence that mite parasitoids can negatively influence host immunity.Moreover,it provides insights into the biocontrol potential of mite parasitoids and their interactions with hosts.展开更多
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua...Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution.展开更多
It has been reported that C-type lectins(CTLs),which are pattern recognition receptors of the insect innate immunity response,may compete with Cry toxin for the receptor alkaline phosphatase to decrease its toxicity i...It has been reported that C-type lectins(CTLs),which are pattern recognition receptors of the insect innate immunity response,may compete with Cry toxin for the receptor alkaline phosphatase to decrease its toxicity in insects.However,to date,which CTLs affect larval susceptibility to Bt in Spodoptera exigua is not clear.In this study,33 CTL genes were identified from S.exigua.Based on the number of carbohydrate-recognition domains(CRDs)and the domain architectures,they were classified into three groups:(1)nineteen CTL-S(single-CRD),(2)eight immulectin(dual-CRD)and(3)six CTL-X(CRD with other domains).RT-qPCR analysis revealed that expression levels of SeCTL-S15,IML-4 and CTL-X6 were upregulated after challenge with Bt and Cry1Ab.Tissue and developmental stage expression analysis showed that only SeCTL-S15 was mainly expressed in the midgut and larva,respectively.Knockdown of SeCTL-S15 significantly increased Bt susceptibility,as indicated by reduced survival and larval weight.These results suggest that CTL-S15 might play a vital role in the low susceptibility of larvae to Bt in S.exigua.Our results provide new insights into CTL function in insects.展开更多
Spodoptera litura is the most threatening pest in lotus production,seriously affecting the lotus yield and quality.Emamectin benzoate and chlorantraniliprole,the main insecticides for controlling S.litura on vegetable...Spodoptera litura is the most threatening pest in lotus production,seriously affecting the lotus yield and quality.Emamectin benzoate and chlorantraniliprole,the main insecticides for controlling S.litura on vegetables,are widely used by farmers to control S.litura on lotus plants.To determine the application concentrations,control effects,and safety of the two insecticides in lotus fields,indoor experiments were conducted to determine the control effects of 200 g/L chlorantraniliprole(SC)and 5%emamectin benzoate(WDG),and the residues of the two insecticides in the water,lotus leaves,and lotus seeds after field application were determined by HPLC-MS/MS.The indoor experiment results showed that chlorantraniliprole and emamectin benzoate both had good control effects on S.litura,with the median lethal concentrations(LC50)of 17.700 and 1.694 mg/L,respectively.After unmanned aerial vehicle spraying of emamectin benzoate at 20 g/667m^(2),there was no residue of emamectin benzoate in the water or lotus leaves after 5 d.After spraying of chlorantraniliprole at 20 mL/667m^(2),the residual amounts in the water and lotus leaves after 9 d were 0.005 and 0.007 mg/L,respectively.No residue of the two insecticides was detected in lotus seeds(dry and fresh)2 h after spraying.Therefore,it was recommended that chlorantraniliprole and emamectin benzoate can be used to control S.litura in lotus fields during the growth period,while attention should be paid to the application interval for safety.Considering the safe harvesting of lotus seeds and leaves,it was recommended that the preharvest intervals of chlorantraniliprole and 5%emamectin benzoate should be 9 d.展开更多
In Côte d’Ivoire, maize (Zea mays L) is the second most cultivated cereal after rice. Since the first report of Spodoptera frugiperda in Côte d’Ivoire, maize production in the northern regions has been aff...In Côte d’Ivoire, maize (Zea mays L) is the second most cultivated cereal after rice. Since the first report of Spodoptera frugiperda in Côte d’Ivoire, maize production in the northern regions has been affected resulting in maize production losses. This study aims to study the seasonal dynamic of Spodoptera frugiperda in maize fields in the sub-Sudanese zone, main zone of maize cultivation in Côte d’Ivoire. The study was done using pheromone trap lures. The results revealed a variation in the moth population at various growth stages during rainy and dry seasons. Notably, the highest numbers of moths were consistently trapped during the whorl stage with counts ranging from 131 ± 35.7 during the rainy season to 70.6 ± 15.01 in the dry season. The lowest numbers of moths were observed during pod maturation, with counts ranging from 30.3 ± 13.05 during the rainy season to 11.7 ± 3.05 in the dry season. Between the 7<sup>th</sup> and 21<sup>st</sup> days after sowing, the count of moths displayed a consistent upward trajectory, reaching 188 moths during the rainy season. The damages were particularly observed at whorl stage. The relationship between the numbers of moths and some climatic variables revealed a negative correlation between moths numbers and rainfall (r= −0.44) and relative humidity (r= −0.684). In contrast, there were positive relationships with temperature (r = 0.16), highlighting the significant impact of temperature changes on moth population dynamics. The research highlights the need for integrated pest management strategies that consider climatic factors and growth stages of maize to mitigate the impact of this insect pest on maize.展开更多
[Objective] The aim was to learn the resistance of different tissues and organs of transgenic cotton to Spodoptera exigua （Hbner）. [Method] Flowers,the 1st,the 3rd,the 6th and the 14th leaves from the top of 33B,GK1...[Objective] The aim was to learn the resistance of different tissues and organs of transgenic cotton to Spodoptera exigua （Hbner）. [Method] Flowers,the 1st,the 3rd,the 6th and the 14th leaves from the top of 33B,GK12 and SGK321 were used to feed S. exigua neonates respectively. Survival larvae and dead ones were counted on the 3rd,the 7th,the 10th,the 16th and the 19th day; meanwhile,the pupae amount was recorded,and the pupae weight was measured at the 24th h after pupation. [Result] The survival curves,pupation rates and pupae weights of S. exigua feeding on different tissues of transgenic cotton were not significantly different from those of S. exigua feeding on the corresponding tissues of conventional cotton; pupation rate of S. exigua feeding on different leaves of the same cotton variety were not significantly different from each other,but all higher than that of S. exigua feeding on the flowers of that cotton; and there were no differences among pupation weights of S. exigua feeding on different leaves or flowers of the same cotton variety. [Conclusion] Transgenic cotton showed weak resistance to S. exigua. Hence,in the transgenic cotton fields,more attention should be paid to occurrence trend of S. exigua and its control.展开更多
[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl...[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl （α-T） with benzene rings. Photoactivated activities on Spodoptera litura （SL） cells, singlet oxygen with UV and photostability of photosensitizers were investigated. [Result] The cytotoxicity of pho-tosensitizer 2,5-diphenylthiophene on SL cells was 0.22 and 0.16 μg/ml after treat-ment for 24 and 48 h, respectively, while that of 2,5-dithienylethynylthiophene on SL cells was 0.06 and 0.04 μg/ml. Singlet oxygen of 2,5-diphenylthiophene and 2,5-dithienylethynylthiophene was 1.047 5, 1.529 4 μg/mmol under UV, respectively. Degradation dynamic equations of 2,5-diphenylthiophene and 2,5-dithienylethynylthio-phene in methanol were Ct= 5.227 1e-0.006 1t, Ct= 5.084 2e-0.097 3t and half life was 111.79, 7.12 h. [Conclusion] Photosensitizer 2,5-diphenylthiophene has high singlet oxygen production ability, and high photoactivated cytotoxicity on SL cells under UV. Moreover, 2,5-diphenylthiophene has overcome the deficiency of photoactivated in-secticides, which is not applied directly in field because it degrades quickly in the environment.展开更多
[Objective] The study was aimed to determine and evaluate control effect and security of 20% tebufenozide SC against Spodoptera exigua HObner, which would provide technical support for its promotion and utilization. [...[Objective] The study was aimed to determine and evaluate control effect and security of 20% tebufenozide SC against Spodoptera exigua HObner, which would provide technical support for its promotion and utilization. [ Method] By using foliar spray method, control effects of different concentration of 20% tebufenozide SC and 25 g/L deltamethrin EC against S. exigua were determined. [ Result] 20% tebufenozide SC had better control effects on S. exigua. After spraying for 3 and 7 d, control effects of 20% tebufenozide SC in each treatment could reach 81% and 84%, which was higher than 25 g/L deltamethdn EC treatment. [ Conclusion] 20% tebufenozide SC for controlling S. exigua had good effect, which had permanent effectiveness for over 7 d. It also caused less environmental pollution, and was safe to cabbage, being the ideal pesticide for controlling S. exigua in vegetables.展开更多
The laboratory bioassay and field control efficacy of Spodoptera litura nucleopolyhedrovirus（Spli NPV） Chenzhou strain were preliminarily examined. The efficient artificial propagation method was to feed the host la...The laboratory bioassay and field control efficacy of Spodoptera litura nucleopolyhedrovirus（Spli NPV） Chenzhou strain were preliminarily examined. The efficient artificial propagation method was to feed the host larvae with virus suspension,and the average mortality of the insects was 65.0%. The death peak of the pests appeared 4-8 d after virus infection. The high temperature, high humidity and poor light could help the virus infection and propagation. Filed control efficacy of Chenzhou strain was 86.6% in laboratory, which was better than of another commercial strain. The corrected control efficacy of this strain was 88.4% the field, which was higher than that of avermectin pesticide significantly. It was detected that the occlusion body（OB） concentration of the initial virus＇ s stock solution was 1.03×1011OBs/ml,and it was a strong SpliNPV strain, as it showed an excellent efficacy to control the pest Spodoptera litura, and thus there will be a good prospect of application and development of this SpliNPV strain.展开更多
[Objective] The paper was to promote using synthetic sex pheromone lures to control tobacco cutworm moth（Spodoptera litura Fabricius） .[Method] Three layers of pheromone traps for S.litura were set in the field at t...[Objective] The paper was to promote using synthetic sex pheromone lures to control tobacco cutworm moth（Spodoptera litura Fabricius） .[Method] Three layers of pheromone traps for S.litura were set in the field at the density of 26 m×26 m（one trap/676 m2） to carry out field control test.[Result] The amount of egg massed reduced by 62.16% after trapping by sex pheromone under the density,and the larvae population was equivalent to those in the conventional control field with pesticides,the control effect was continuous,stable and significant.The larger the control area was,the better the effect was.[Conclusion] Using sex pheromone could effectively control S.litura and reduce pesticide usage for over 80% with economic,safe and efficient features,which should be incorporated into the technical control system of S.litura.展开更多
The fall armyworm(FAW),Spodoptera frugiperda is one of the most damaging crop pests,and it has become major threat to the food security of many countries.In order to monitor possible invasion of this pest into China,a...The fall armyworm(FAW),Spodoptera frugiperda is one of the most damaging crop pests,and it has become major threat to the food security of many countries.In order to monitor possible invasion of this pest into China,a searchlight trap was established in March 2018 in western Yunnan Province,China,where it has served as the"first station"for many pests that have migrated from Myanmar to China.A number of suspected FAW moths were captured and identified by DNA sequencing.The results showed that the FAW moth was first captured on December 11 and formed its first immigration peak in mid-December 2018.DNA detection revealed that the early invading FAW population was the"corn-strain".The field survey indicated that the pest mainly colonized corn in Pu’er,Dehong and Baoshan areas.Migration trajectory simulation implied that the moths might have mainly come from the eastern area in the mid-latitude region of Myanmar(20-25°N,94-100°E).This case study confirmed the first immigration of FAW into China,and will be helpful for guiding monitoring and management work to control this pest.展开更多
The beet armyworm,Spodoptera exigua （Lepidoptera：Noctuidae）,is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citru...The beet armyworm,Spodoptera exigua （Lepidoptera：Noctuidae）,is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citrus crops.In this study,performance and subsequent enzyme activity of beet armyworm reared on host plants from five families were investigated.Significant differences were found in development,fecundity and enzyme activity on different host plants.Survival rate was the highest （42.8%） on asparagus lettuce （Lactuca sativar var.asparagina） and the lowest （17.0%） on sweet pepper （Capsicum annuum）.Larval duration was the shortest on asparagus lettuce （12.0 d）,and was 43.4% longer on sweet peppers （21.2 d）.The activity of acetylcholine esterase （AChE） and carboxylesterase （CarE） in 3rd instar larvae,and soluble carbohydrate and crude protein contents in different host plants were determined.AChE activity was the highest in the larvae feeding on Chinese cabbage （Brassica rapa）,but declined by nearly 60% on maize （Zea mays） seedlings.The ratio of soluble carbohydrate content to crude protein content in host plants was found to have a positive effect on oviposition and a negative correlation with larval duration and life time （from larval to adult stages） of the insect.展开更多
基金funded by the National Key Research and Development Program of China(Grant number 2022YFD1400700)Initiative Scientific Research Program,Institute of Zoology,Chinese Academy of Sciences(Grant number 2023IOZ010).
文摘Spodoptera frugiperda multiple nucleopolyhedrovirus(SfMNPV),belonging to the species Alphabaculovirus spofrugiperdae,has been recently registered as an insecticide in China.This virus has a specific effect on the global major agricultural pest Spodoptera frugiperda.To gain insights into viral infection,replication processes,and the complex formation of viral particles,in vitro studies using cell lines are essential tools.Although the IPLB-Sf9 and IPLB-Sf21 cell lines derived from S.frugiperda are widely used for studies on the infection and replication mechanisms of Autographa californica multiple nucleopolyhedrovirus(AcMNPV),their capacity to produce viral polyhedra after SfMNPV infection is not optimal.To address this limitation,a novel cell line named IOZCAS-Sf-1 was developed from a S.frugiperda population in Yunnan,China.The mitochondrial COX1 gene analysis confirmed the species origin of the IOZCAS-Sf-1 cell line.Furthermore,a comparative study was carried out to contrast the COX1 gene sequence of this novel cell line with that of IPLB-Sf9,highlighting the distinctions between the two.Importantly,the IOZCAS-Sf-1 cells exhibited a remarkable ability to generate polyhedra when infected with AcMNPV and SfMNPV,respectively.Consequently,this cellular lineage is considered a promising and valuable resource.It serves not only to investigate the molecular mechanisms of viral replication and its impact on host cells,but also to explore the transfection efficiency of SfMNPV DNA.This exploration further expands into its potential application in recombinant DNA experiments,laying a theoretical groundwork for the advancement of more effective biopesticides and sustainable agricultural practices.
基金funded by the Shenzhen Science and Technology Program,China(KQTD20180411143628272)the Special Funds for Science Technology Innovation and Industrial Development of Shenzhen Dapeng New District,China(pt202101-02)the National Key R&D Program of China(2022YFE0116500).
文摘Spodoptera frugiperda is a highly destructive pest that has become a global problem due to its robust reproductive and migratory capabilities.Transient receptor potential(TRP)channels,which constitute a vast ion channel family,play pivotal roles in sensing the external environment and maintaining internal homeostasis in insects.TRP channels have been widely investigated for their critical roles in regulating various insect behaviors in recent years.In this study,we identified 15 TRP gene loci encoding 26 transcripts in the genome of S.frugiperda and analyzed their expression profiles at different developmental stages.The results revealed that S.frugiperda possesses four TRPC genes,six TRPA genes,one TRPM gene,two TRPV genes,one TRPN gene,and one TRPML gene,while a canonical TRPP is absent.Moreover,the SfruTRPA1 was functionally characterized using the Xenopus oocyte expression system.The results showed that SfruTRPA1 is activated by temperature increases from 20 to 45℃,and there is no significant desensitization after repeated stimuli within the same temperature range.Additionally,SfruTRPA1 is activated by certain natural chemicals,including allyl isothiocyanate(AITC)and cinnamaldehyde(CA).These findings provide valuable insights to the TRP genes in S.frugiperda.
基金funded by the National Natural Science Foundation of China(32060637 and 32260708)the Highlevel Talent Innovation and Entrepreneurship Funding Project in Guizhou Province,China((2021)01)+3 种基金the Guizhou Provincial Science and Technology Innovation Talent Team Project,China(Qian Ke He Pingtai RencaiCXTD(2021)004)the Systematic and Applied Acarology Society International Joint Project,England(2022(01))the Growth Project of Youth Talent in Ordinary Universities in Guizhou Province,China((2021)079)the Natural Science Special Project in Guizhou University,China((2020)02)。
文摘Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic losses in agriculture.Pyemotes zhonghuajia,a newly identified mite parasitoid,has shown potential for controlling various agricultural insect pests.Therefore,this study tested the performance of P.zhonghuajia in parasitising S.frugiperda.We also investigated the sublethal effects of parasitism by P.zhonghuajia on host fitness traits,transgenerational impacts,and cellular and humoral immunity.Our result showed that the fifth-instar larvae of S.frugiperda parasitised by 40 P.zhonghuajia were all dead(i.e.,a lethal effect),while parasitism by 5 or 10 P.zhonghuajia was considered sublethal since many S.frugiperda survived to adulthood and produced offspring after mating.The sublethal influences from parasitism by P.zhonghuajia resulted in reduced pupal weight,adult emergence rate and fecundity,but increased developmental time and longevity.Parasitism at both lethal(40 mites)and sublethal(10 mites)levels impaired the cellular and humoral immunity of S.frugiperda.This study presents the first empirical evidence that mite parasitoids can negatively influence host immunity.Moreover,it provides insights into the biocontrol potential of mite parasitoids and their interactions with hosts.
基金partially supported by the Open Project Program from the Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization(Ministry of Agriculture and Rural Affairs),China(212103)。
文摘Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution.
基金supported by the National Key Research and Development Program of China(2022YFD1401200)the National Natural Science Foundation of China(32172397).
文摘It has been reported that C-type lectins(CTLs),which are pattern recognition receptors of the insect innate immunity response,may compete with Cry toxin for the receptor alkaline phosphatase to decrease its toxicity in insects.However,to date,which CTLs affect larval susceptibility to Bt in Spodoptera exigua is not clear.In this study,33 CTL genes were identified from S.exigua.Based on the number of carbohydrate-recognition domains(CRDs)and the domain architectures,they were classified into three groups:(1)nineteen CTL-S(single-CRD),(2)eight immulectin(dual-CRD)and(3)six CTL-X(CRD with other domains).RT-qPCR analysis revealed that expression levels of SeCTL-S15,IML-4 and CTL-X6 were upregulated after challenge with Bt and Cry1Ab.Tissue and developmental stage expression analysis showed that only SeCTL-S15 was mainly expressed in the midgut and larva,respectively.Knockdown of SeCTL-S15 significantly increased Bt susceptibility,as indicated by reduced survival and larval weight.These results suggest that CTL-S15 might play a vital role in the low susceptibility of larvae to Bt in S.exigua.Our results provide new insights into CTL function in insects.
基金Supported by Agricultural Science and Technology Innovation Fund Project of Hunan Province(2023CX98)Hunan Vegetable Industry Technology System(HARS-04)Fund for Innovation and Entrepreneurship of Technological Enterprises in Yueyang City(2023081700020)。
文摘Spodoptera litura is the most threatening pest in lotus production,seriously affecting the lotus yield and quality.Emamectin benzoate and chlorantraniliprole,the main insecticides for controlling S.litura on vegetables,are widely used by farmers to control S.litura on lotus plants.To determine the application concentrations,control effects,and safety of the two insecticides in lotus fields,indoor experiments were conducted to determine the control effects of 200 g/L chlorantraniliprole(SC)and 5%emamectin benzoate(WDG),and the residues of the two insecticides in the water,lotus leaves,and lotus seeds after field application were determined by HPLC-MS/MS.The indoor experiment results showed that chlorantraniliprole and emamectin benzoate both had good control effects on S.litura,with the median lethal concentrations(LC50)of 17.700 and 1.694 mg/L,respectively.After unmanned aerial vehicle spraying of emamectin benzoate at 20 g/667m^(2),there was no residue of emamectin benzoate in the water or lotus leaves after 5 d.After spraying of chlorantraniliprole at 20 mL/667m^(2),the residual amounts in the water and lotus leaves after 9 d were 0.005 and 0.007 mg/L,respectively.No residue of the two insecticides was detected in lotus seeds(dry and fresh)2 h after spraying.Therefore,it was recommended that chlorantraniliprole and emamectin benzoate can be used to control S.litura in lotus fields during the growth period,while attention should be paid to the application interval for safety.Considering the safe harvesting of lotus seeds and leaves,it was recommended that the preharvest intervals of chlorantraniliprole and 5%emamectin benzoate should be 9 d.
文摘In Côte d’Ivoire, maize (Zea mays L) is the second most cultivated cereal after rice. Since the first report of Spodoptera frugiperda in Côte d’Ivoire, maize production in the northern regions has been affected resulting in maize production losses. This study aims to study the seasonal dynamic of Spodoptera frugiperda in maize fields in the sub-Sudanese zone, main zone of maize cultivation in Côte d’Ivoire. The study was done using pheromone trap lures. The results revealed a variation in the moth population at various growth stages during rainy and dry seasons. Notably, the highest numbers of moths were consistently trapped during the whorl stage with counts ranging from 131 ± 35.7 during the rainy season to 70.6 ± 15.01 in the dry season. The lowest numbers of moths were observed during pod maturation, with counts ranging from 30.3 ± 13.05 during the rainy season to 11.7 ± 3.05 in the dry season. Between the 7<sup>th</sup> and 21<sup>st</sup> days after sowing, the count of moths displayed a consistent upward trajectory, reaching 188 moths during the rainy season. The damages were particularly observed at whorl stage. The relationship between the numbers of moths and some climatic variables revealed a negative correlation between moths numbers and rainfall (r= −0.44) and relative humidity (r= −0.684). In contrast, there were positive relationships with temperature (r = 0.16), highlighting the significant impact of temperature changes on moth population dynamics. The research highlights the need for integrated pest management strategies that consider climatic factors and growth stages of maize to mitigate the impact of this insect pest on maize.
基金Supported by National Transgenic Major Project ( Safe Monitoring Technique of Transgenic Organism 2008ZX08012-004)~~
文摘[Objective] The aim was to learn the resistance of different tissues and organs of transgenic cotton to Spodoptera exigua （Hbner）. [Method] Flowers,the 1st,the 3rd,the 6th and the 14th leaves from the top of 33B,GK12 and SGK321 were used to feed S. exigua neonates respectively. Survival larvae and dead ones were counted on the 3rd,the 7th,the 10th,the 16th and the 19th day; meanwhile,the pupae amount was recorded,and the pupae weight was measured at the 24th h after pupation. [Result] The survival curves,pupation rates and pupae weights of S. exigua feeding on different tissues of transgenic cotton were not significantly different from those of S. exigua feeding on the corresponding tissues of conventional cotton; pupation rate of S. exigua feeding on different leaves of the same cotton variety were not significantly different from each other,but all higher than that of S. exigua feeding on the flowers of that cotton; and there were no differences among pupation weights of S. exigua feeding on different leaves or flowers of the same cotton variety. [Conclusion] Transgenic cotton showed weak resistance to S. exigua. Hence,in the transgenic cotton fields,more attention should be paid to occurrence trend of S. exigua and its control.
基金Supported by Science and Technology Support Program of Jiangsu Province(Agricultural Project)(BE2012346)Science and Technology Projects for Social Development of Yangzhou City,China(2012110)Natural Science Foundation of the Jiangsu Higher Education Institutions of China(13KJB210010)~~
文摘[Objective ]The aim of this study was to improve the photostability of pho-tosensitizers. [Method] 2,5-Diphenylthiophene and 2,5-dithienylethynylthiophene were synthesized by replacing thiophene rings of α-terthienyl （α-T） with benzene rings. Photoactivated activities on Spodoptera litura （SL） cells, singlet oxygen with UV and photostability of photosensitizers were investigated. [Result] The cytotoxicity of pho-tosensitizer 2,5-diphenylthiophene on SL cells was 0.22 and 0.16 μg/ml after treat-ment for 24 and 48 h, respectively, while that of 2,5-dithienylethynylthiophene on SL cells was 0.06 and 0.04 μg/ml. Singlet oxygen of 2,5-diphenylthiophene and 2,5-dithienylethynylthiophene was 1.047 5, 1.529 4 μg/mmol under UV, respectively. Degradation dynamic equations of 2,5-diphenylthiophene and 2,5-dithienylethynylthio-phene in methanol were Ct= 5.227 1e-0.006 1t, Ct= 5.084 2e-0.097 3t and half life was 111.79, 7.12 h. [Conclusion] Photosensitizer 2,5-diphenylthiophene has high singlet oxygen production ability, and high photoactivated cytotoxicity on SL cells under UV. Moreover, 2,5-diphenylthiophene has overcome the deficiency of photoactivated in-secticides, which is not applied directly in field because it degrades quickly in the environment.
基金Supported by Hunan Nature Foundation(07JJ6055)Hunan Provincial Department of Education Foundation(07C362)Hunan Agricultural University Talent Foundation(2006WD026)~~
文摘[Objective] The study was aimed to determine and evaluate control effect and security of 20% tebufenozide SC against Spodoptera exigua HObner, which would provide technical support for its promotion and utilization. [ Method] By using foliar spray method, control effects of different concentration of 20% tebufenozide SC and 25 g/L deltamethrin EC against S. exigua were determined. [ Result] 20% tebufenozide SC had better control effects on S. exigua. After spraying for 3 and 7 d, control effects of 20% tebufenozide SC in each treatment could reach 81% and 84%, which was higher than 25 g/L deltamethdn EC treatment. [ Conclusion] 20% tebufenozide SC for controlling S. exigua had good effect, which had permanent effectiveness for over 7 d. It also caused less environmental pollution, and was safe to cabbage, being the ideal pesticide for controlling S. exigua in vegetables.
基金Supported by Science and Technology Achievement Transformation Fund of Changsha Municipal Bureau of Science and Technology(K1301004-21)National Natural Science Foundation of China(31101460)Science and Technology Fund of China Tobacco Hunan Industrial Co.,Ltd.(09-11Aa30)~~
文摘The laboratory bioassay and field control efficacy of Spodoptera litura nucleopolyhedrovirus（Spli NPV） Chenzhou strain were preliminarily examined. The efficient artificial propagation method was to feed the host larvae with virus suspension,and the average mortality of the insects was 65.0%. The death peak of the pests appeared 4-8 d after virus infection. The high temperature, high humidity and poor light could help the virus infection and propagation. Filed control efficacy of Chenzhou strain was 86.6% in laboratory, which was better than of another commercial strain. The corrected control efficacy of this strain was 88.4% the field, which was higher than that of avermectin pesticide significantly. It was detected that the occlusion body（OB） concentration of the initial virus＇ s stock solution was 1.03×1011OBs/ml,and it was a strong SpliNPV strain, as it showed an excellent efficacy to control the pest Spodoptera litura, and thus there will be a good prospect of application and development of this SpliNPV strain.
基金Supported by Project in Yunnan Branch of China National Tobacco Company(2010YN77)~~
文摘[Objective] The paper was to promote using synthetic sex pheromone lures to control tobacco cutworm moth（Spodoptera litura Fabricius） .[Method] Three layers of pheromone traps for S.litura were set in the field at the density of 26 m×26 m（one trap/676 m2） to carry out field control test.[Result] The amount of egg massed reduced by 62.16% after trapping by sex pheromone under the density,and the larvae population was equivalent to those in the conventional control field with pesticides,the control effect was continuous,stable and significant.The larger the control area was,the better the effect was.[Conclusion] Using sex pheromone could effectively control S.litura and reduce pesticide usage for over 80% with economic,safe and efficient features,which should be incorporated into the technical control system of S.litura.
基金supported by the National Natural Science Foundation of China(31727901)。
文摘The fall armyworm(FAW),Spodoptera frugiperda is one of the most damaging crop pests,and it has become major threat to the food security of many countries.In order to monitor possible invasion of this pest into China,a searchlight trap was established in March 2018 in western Yunnan Province,China,where it has served as the"first station"for many pests that have migrated from Myanmar to China.A number of suspected FAW moths were captured and identified by DNA sequencing.The results showed that the FAW moth was first captured on December 11 and formed its first immigration peak in mid-December 2018.DNA detection revealed that the early invading FAW population was the"corn-strain".The field survey indicated that the pest mainly colonized corn in Pu’er,Dehong and Baoshan areas.Migration trajectory simulation implied that the moths might have mainly come from the eastern area in the mid-latitude region of Myanmar(20-25°N,94-100°E).This case study confirmed the first immigration of FAW into China,and will be helpful for guiding monitoring and management work to control this pest.
基金supported by the Chongqing Science & Technology Commission,China (2005BA1014)the Chongqing Education Commission,China (KJ060302)
文摘The beet armyworm,Spodoptera exigua （Lepidoptera：Noctuidae）,is an economically important pest of crops worldwide,attacking plants from over 20 families including trans-continental agricultural cotton,corn and citrus crops.In this study,performance and subsequent enzyme activity of beet armyworm reared on host plants from five families were investigated.Significant differences were found in development,fecundity and enzyme activity on different host plants.Survival rate was the highest （42.8%） on asparagus lettuce （Lactuca sativar var.asparagina） and the lowest （17.0%） on sweet pepper （Capsicum annuum）.Larval duration was the shortest on asparagus lettuce （12.0 d）,and was 43.4% longer on sweet peppers （21.2 d）.The activity of acetylcholine esterase （AChE） and carboxylesterase （CarE） in 3rd instar larvae,and soluble carbohydrate and crude protein contents in different host plants were determined.AChE activity was the highest in the larvae feeding on Chinese cabbage （Brassica rapa）,but declined by nearly 60% on maize （Zea mays） seedlings.The ratio of soluble carbohydrate content to crude protein content in host plants was found to have a positive effect on oviposition and a negative correlation with larval duration and life time （from larval to adult stages） of the insect.
