Background Anthonomus grandis grandis is the main cotton pest in the Americas,with the potential to become a pest in other continents.The insect uses the plant's reproductive organs for feeding,oviposition,and sur...Background Anthonomus grandis grandis is the main cotton pest in the Americas,with the potential to become a pest in other continents.The insect uses the plant's reproductive organs for feeding,oviposition,and survival strategies in the off-season,sheltering in dry bolls.This study aimed to know the reproductive potential,feeding,longevity,and morphometric characteristics of boll weevils from dry bolls,squares,and traps.Adults were obtained from infested squares,dry bolls,and traps installed in cotton fields and the Caatinga area.Thirty weevil pairs were maintained in the laboratory to assess the oviposition,feeding holes,longevity,and morphometric measurements of the parental and F_(1) generations.Results In the parental generation,boll weevils from traps(the Caatinga area and cotton cultivation)showed greater reproductive potential.Boll weevils from squares and the Caatinga area showed greater feeding activity compared with those from cotton cultivation.Greater rostrum length,thorax+abdomen length,and abdomen width were observed in boll weevils from cotton cultivation and dry bolls.The origin of boll weevils parental generation did not affect progeny emergence time.The F_(1) generation of boll weevils showed significant differences in average longevity depending on the origin of different microhabitats.Furthermore,differences in rostrum lengths were observed,with the boll weevils coming from traps installed in cotton cultivation,the Caatinga area,and dry bolls being the largest.Regarding thorax+abdomen length and abdomen width,the highest values were observed in those from the Caatinga area and cotton cultivation.Conclusion It was proven that dry bolls did not affect the reproductive,feeding,and longevity performance of boll weevils,enabling better insect fitness(reproduction and size)in relation to those coming from squares.The use of dry bolls as off-season shelter is an important survival strategy for the boll weevil.展开更多
Aphis gossypii has become increasingly difficult to manage due to its strong insecticide resistance.In the laboratory,we established sulfoxaflor-resistant and acetamiprid-resistant strains in two A.gossypii population...Aphis gossypii has become increasingly difficult to manage due to its strong insecticide resistance.In the laboratory,we established sulfoxaflor-resistant and acetamiprid-resistant strains in two A.gossypii populations with different basal insecticide resistance levels,and evaluated the effects of basal insecticide resistance on the resistance development and cross-resistance,as well as differences in fitness.Under the same selection pressure,Yarkant A.gossypii(with low basal insecticide resistance)evolved resistance to sulfoxaflor and acetamiprid more quickly than Jinghe A.gossypii(with high basal insecticide resistance),and the evolution of A.gossypii resistance to sulfoxaflor developed faster than acetamiprid in both Yarkant and Jinghe,Xingjiang,China.The sulfoxaflor-resistant strains selected from Yarkant and Jinghe developed significant cross-resistance to acetamiprid,imidacloprid,thiamethoxam and pymetrozine;while the acetamiprid-resistant strains developed significant cross-resistance to sulfoxaflor,imidacloprid,thiamethoxam,pymetrozine,and chlorpyrifos.The relative fitness of A.gossypii decreased as the resistance to sulfoxaflor and acetamiprid developed.The relative fitness levels of the sulfoxaflor-resistant strains(Yarkant-SulR and Jinghe-SulR)were lower than those of the acetamipridresistant strains(Yarkant-AceR and Jinghe-AceR).In addition,the relative fitness levels of sulfoxaflor-and acetamiprid-resistant strains were lower in Jinghe than in Yarkant.In summary,basal insecticide resistance of A.gossypii and insecticide type affected the evolution of resistance to insecticides in A.gossypii,as well as cross-resistance to other insecticides.The sulfoxaflor-and acetamiprid-resistant A.gossypii strains had obvious fitness costs.The results of this work will contribute to the insecticide resistance management and integrated management of A.gossypii.展开更多
基金supported by Fundacao de Amparoà Pesquisa do Estado da Bahiathe Coordenacao de Aperfeicoamento de Pessoal de Nível Superior Foundation(Finance Code 001)for financial supportBahia Association of Cotton Producers。
文摘Background Anthonomus grandis grandis is the main cotton pest in the Americas,with the potential to become a pest in other continents.The insect uses the plant's reproductive organs for feeding,oviposition,and survival strategies in the off-season,sheltering in dry bolls.This study aimed to know the reproductive potential,feeding,longevity,and morphometric characteristics of boll weevils from dry bolls,squares,and traps.Adults were obtained from infested squares,dry bolls,and traps installed in cotton fields and the Caatinga area.Thirty weevil pairs were maintained in the laboratory to assess the oviposition,feeding holes,longevity,and morphometric measurements of the parental and F_(1) generations.Results In the parental generation,boll weevils from traps(the Caatinga area and cotton cultivation)showed greater reproductive potential.Boll weevils from squares and the Caatinga area showed greater feeding activity compared with those from cotton cultivation.Greater rostrum length,thorax+abdomen length,and abdomen width were observed in boll weevils from cotton cultivation and dry bolls.The origin of boll weevils parental generation did not affect progeny emergence time.The F_(1) generation of boll weevils showed significant differences in average longevity depending on the origin of different microhabitats.Furthermore,differences in rostrum lengths were observed,with the boll weevils coming from traps installed in cotton cultivation,the Caatinga area,and dry bolls being the largest.Regarding thorax+abdomen length and abdomen width,the highest values were observed in those from the Caatinga area and cotton cultivation.Conclusion It was proven that dry bolls did not affect the reproductive,feeding,and longevity performance of boll weevils,enabling better insect fitness(reproduction and size)in relation to those coming from squares.The use of dry bolls as off-season shelter is an important survival strategy for the boll weevil.
基金supported by the National Key R&D Program of China(2022YFD1400300)the Open Fund of Key Laboratory of Integrated Pest Management on Crops in Northwestern Oasis,Ministry of Agriculture and Rural Affairs of China(KFJJ202204)the China Agriculture Research System(CARS-15-20)。
文摘Aphis gossypii has become increasingly difficult to manage due to its strong insecticide resistance.In the laboratory,we established sulfoxaflor-resistant and acetamiprid-resistant strains in two A.gossypii populations with different basal insecticide resistance levels,and evaluated the effects of basal insecticide resistance on the resistance development and cross-resistance,as well as differences in fitness.Under the same selection pressure,Yarkant A.gossypii(with low basal insecticide resistance)evolved resistance to sulfoxaflor and acetamiprid more quickly than Jinghe A.gossypii(with high basal insecticide resistance),and the evolution of A.gossypii resistance to sulfoxaflor developed faster than acetamiprid in both Yarkant and Jinghe,Xingjiang,China.The sulfoxaflor-resistant strains selected from Yarkant and Jinghe developed significant cross-resistance to acetamiprid,imidacloprid,thiamethoxam and pymetrozine;while the acetamiprid-resistant strains developed significant cross-resistance to sulfoxaflor,imidacloprid,thiamethoxam,pymetrozine,and chlorpyrifos.The relative fitness of A.gossypii decreased as the resistance to sulfoxaflor and acetamiprid developed.The relative fitness levels of the sulfoxaflor-resistant strains(Yarkant-SulR and Jinghe-SulR)were lower than those of the acetamipridresistant strains(Yarkant-AceR and Jinghe-AceR).In addition,the relative fitness levels of sulfoxaflor-and acetamiprid-resistant strains were lower in Jinghe than in Yarkant.In summary,basal insecticide resistance of A.gossypii and insecticide type affected the evolution of resistance to insecticides in A.gossypii,as well as cross-resistance to other insecticides.The sulfoxaflor-and acetamiprid-resistant A.gossypii strains had obvious fitness costs.The results of this work will contribute to the insecticide resistance management and integrated management of A.gossypii.