Effects of sublethal concentrations of nitenpyram on resistance substances in rice and reproductive parameters of the brown planthopper Nilaparvata lugens
To elucidate the control efficacy of sulfoxaflor against the brown planthopper,Nilaparvata lu-gens,the rice stem impregnation method was employed to determine the effects of sublethal concentra-tions of nitenpyram on physiological and biochemical indices of rice,as well as on the reproductive ca-pacity of female brown planthoppers. The results showed that the oxalic acid content of rice treated with sublethal concentrations of nitenpyram for two and four days showed no significant difference at two days and increased by 20.5％ at four days. Flavonoids levels increased by 9.6％ and 40.6％,respectively. The content of free amino acids decreased by 20.1％ at two days and 42.4％ at four days,respectively. The sucrose content showed no significant difference at two days but increased by 38.5％ at four days after treatment with sublethal concentrations of nitenpyram. The sublethal concentration of nitenpyram significantly affected the reproduction of the brown planthopper. Soluble protein content in the ovaries of female adults decreased by 31.2％ and 40.9％ on days two and four post-emergence,respectively,and by 19.0％ and 38.8％ in the fat body. Nitenpyram inhibited ovarian development in female adults,with Nilaparvata lugens vitellogenin (NlVg) gene expression showing no significant difference at two days af-ter emergence and a 57.5％ decrease at four days after emergence. Additionally,it significantly affected the reproductive capacity of the brown planthopper,with the number of eggs laid by females decreasing by 58.1％,the oviposition period shortening by 36.7％,and lifespan decreasing by 28.0％,although there was no significant impact on the pre-oviposition period. This indicates that sublethal concentrations of ni-tenpyram induce an increase in secondary metabolites in rice to enhance resistance against the brown pl-anthopper and significantly impact the reproductive capacity of the pest.
万方数据
维普
