Lethal and sublethal effects of cyantraniliprole on Helicoverpa assulta (Lepidoptera: Noctuidae)

Abstract

Cyantraniliprole is a novel anthranilic diamide insecticide registered for the control of many sucking and chewing insect pests including the oriental tobacco budworm, Helicoverpa assulta (Guenée), which is an important lepidopteran pest of tobacco in China. This study determined the lethal and sublethal effects of cyantraniliprole on a treated parental generation and on an untreated offspring generation of H. assulta. Cyantraniliprole was incorporated in the diet of 3rd-instar larvae of the parental generation. Cyantraniliprole was highly toxic to the parental generation: after a 72-h feeding period, the LC₅₀ was 0.176mg/L. Cyantraniliprole tended to increase the developmental time of parental larvae, and the LC₃₀ significantly reduced the pupation rate and the pupal weight. Cyantraniliprole also significantly decreased the intrinsic rate of increase (r_m) and finite rate of increase (λ), and increased the doubling time (Dt). Treatment of the parental generation with the LC₃₀ decreased the pupal weight and adult fecundity, and increased adult deformity in the parental and offspring generations. Cyantraniliprole did not significantly affect the pupal period, the percentage of females, or adult longevity in either generation. These results suggest that both the lethal and sublethal effects of cyantraniliprole might suppress H. assulta population growth by reducing the insect's survival, development, and reproduction.

Keywords: Cyantraniliprole; Helicoverpa assulta; Sublethal effect; Toxicity.