Abstract: The sublethal doses （LC₁₀, LC₂₀, and LC₃₀） of chlorpyrifos, endosulfan, cyhalothrin, and imidacloprid to the 1 day-old adults of Adelphocoris saturalis Jakovlev were determined in a glass-vial bioassay, and the sublethal effects of four insecticides at the LC₂₀ dose on A. saturalis were studied. The results showed that the four insecticides significantly reduced the longevity of female and male adults and prolonged the hatching period, while not significantly affected the egg hatching rate. Chlorpyrifos and endosulfan significantly shortened the preovipositon period. Cyhalothrin and imidacloprid significantly decreased the eggs laid per female. After the survived individuals were treated with chlorpyrifos at the LC₁₀ and LC₃₀ doses cross-mated with the untreated adults, the longevity of female and male adults was also reduced. Different cross types at the LC₁₀ dose all decreased the eggs laid per female and the hatching rates, and prolonged the hatching period. The survival rates of subsequent nymphs of LC₃₀♀×CK♂ and LC₃₀♀×LC₃₀♂ were significantly lower than that of the control. These results showed that the sublethal doses of the four insecticides had adverse effects on fecundity of A. saturalis, and mating of treated adults with untreated ones also has an adverse effect on fecundity of their offsprings. This study provides certain guidance for designing the regional IPM program for A. saturalis.

Key words: Adelphocoris suturalis, insecticide, sublethal effect, biological trait, development, reproduction