Impact of low lethal concentrations of buprofezin on biological traits and expression profile of chitin synthase 1 gene (CHS1) in melon aphid, Aphis gossypii

Buprofezin, a chitin synthesis inhibitor that can be used for the control of hemipteran pests, especially melon aphid, Aphis gossypii. The impact of low lethal concentrations of buprofezin on the biological parameters and expression profile of CHS1 gene were estimated for two successive generations of A. gossypii. The present result shows that the LC(15) and LC(30) of buprofezin significantly decreased the fecundity and longevity of both generations. Exposure of F(0) individuals to both concentrations delay the developmental period in F(1). Furthermore, the survival rate, intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R(0)) were reduced significantly in progeny generation at both concentrations. However, the reduction in gross reproductive rate (GRR) was observed only at LC(30). Although, the mean generation time (T) prolonged substantially at LC(30). Additionally, expression of the CHS1 gene was significantly increased in F(0) adults. Significant increase in the relative abundance of CHS1 mRNA transcript was also observed at the juvenile and adult stages of F(1) generation following exposure to LC(15) and LC(30). Therefore, our results show that buprofezin could affect the biological traits by diminishing the chitin contents owing to the inhibition of chitin synthase activity in the succeeding generation of melon aphid.