Evaluation of Lethal Effects of Chlorantraniliprole on Chilo suppressalis and Its Larval Parasitoid, Cotesia chilonis

Chlorantraniliprole was introduced into China from 2008 as a novel insecticide to control the rice stem borer, Chilo suppressalis (Walker). Cotesia chilonis (Matsumura) is the major parasitoid of C. suppressalis. We collected seven populations of C. suppressalis and two populations of C. chilonis in different locations in China in 2009 to investigate the lethal effects of chlorantraniliprole on them. The populations of C. suppressalis from different regions showed various LD50 values ranging from 2.00 to 18.70 ng per larva. Chlorantraniliprole has negligible acute contact toxicity (LC50>500 mg L−1) to C. chilonis and its oral toxicity is also much lower than that of fipronil (>2 800-fold difference in LC50). The results indicated that chlorantraniliprole is a good alterative in rice integrated pest management (IPM) programs. The susceptibility data of C. suppressalis will be useful for monitoring resistance levels in future.