Li Huang1, Mingxing Lu1, Guangjie Han2, Yuzhou Du1, Jianjun Wang3. 1. College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China. 2. Jiangsu Lixiahe Institute of Agricultural Sciences, Yangzhou, China. 3. College of Horticulture and Plant Protection, Yangzhou University, Yangzhou, China. wangjj@yzu.edu.cn.
Abstract
BACKGROUND: The rice stem borer, Chilo suppressalis (Walker), is one of the most damaging rice pests in the world. The sublethal effects of chlorantraniliprole on development,reproduction and mRNA expression levels of vitellogenin gene (CsVg) in C. suppressalis were investigated. RESULTS: Exposure of third-instar larvae to sublethal concentrations of chlorantraniliprole (LC10 and LC30 ) significantly extended larval duration, lowered the mean weight of male pupae and shortened male adult longevity. Pupal duration was significantly prolonged and the mean weight of female pupae was significantly lowered in the LC30 treatment group. While there were no significant sublethal effects on either the adult emergence rate or the egg hatch, the pupation rates in the LC10 treatment group (41.30%) and in the LC30 treatment group (23.98%) were significantly lower than the pupation rate of the control (71.86%), and LC10 and LC30 chlorantraniliprole significantly reduced fecundity, by 32.18 and 52.94% respectively. Furthermore, the expression levels of CsVg mRNA after exposure to LC10 and LC30 chlorantraniliprole significantly decreased, by 42.52 and 47.84% respectively, in 12-h-old female adults. CONCLUSION: Sublethal concentrations of chlorantraniliprole adversely affect the development and reproduction of C. suppressalis. The downregulation of CsVg by chlorantraniliprole might have negative impacts on the fecundity of C. suppressalis.
BACKGROUND: The rice stem borer, Chilo suppressalis (Walker), is one of the most damaging rice pests in the world. The sublethal effects of chlorantraniliprole on development,reproduction and mRNA expression levels of vitellogenin gene (CsVg) in C. suppressalis were investigated. RESULTS: Exposure of third-instar larvae to sublethal concentrations of chlorantraniliprole (LC10 and LC30 ) significantly extended larval duration, lowered the mean weight of male pupae and shortened male adult longevity. Pupal duration was significantly prolonged and the mean weight of female pupae was significantly lowered in the LC30 treatment group. While there were no significant sublethal effects on either the adult emergence rate or the egg hatch, the pupation rates in the LC10 treatment group (41.30%) and in the LC30 treatment group (23.98%) were significantly lower than the pupation rate of the control (71.86%), and LC10 and LC30 chlorantraniliprole significantly reduced fecundity, by 32.18 and 52.94% respectively. Furthermore, the expression levels of CsVg mRNA after exposure to LC10 and LC30 chlorantraniliprole significantly decreased, by 42.52 and 47.84% respectively, in 12-h-old female adults. CONCLUSION: Sublethal concentrations of chlorantraniliprole adversely affect the development and reproduction of C. suppressalis. The downregulation of CsVg by chlorantraniliprole might have negative impacts on the fecundity of C. suppressalis.