Sublethal Effects of Spirotetramat, Cyantraniliprole, and Pymetrozine on IAphis gossypii/I

This study investigated the sublethal effects of three insecticides (spirotetramat, cyantraniliprole, and pymetrozine) on Aphis gossypii. The effects of sublethal concentrations (LC[sub.10] , LC[sub.30] , LC[sub.50] , and LC[sub.70] ) of the insecticides on the developmental period, survival rate, adult longevity, fecundity, and deformity rate were compared with those of the control. Spirotetramat and cyantraniliprole caused malformation in the F[sub.1] but not the F[sub.2] generation of A. gossypii. The net reproductive rate (R[sub.0] ) decreased significantly compared to that of the control (43.8) for all insecticides except cyantraniliprole at the LC[sub.10] (37.5). Therefore, sublethal concentrations (over the LC[sub.30] ) of the three insecticides could aid in the management of A. gossypii by affecting its population density. The toxicity and sublethal effects of three insecticides (spirotetramat, cyantraniliprole, and pymetrozine) on Aphis gossypii, a major agricultural pest, were investigated. The nymphal stage showed greater susceptibility than the adult stage to all the insecticides, with a difference of up to 8.9 times at the LC[sub.50] of spirotetramat. The effects of sublethal concentrations (LC[sub.10] , LC[sub.30] , LC[sub.50] , and LC[sub.70] ) of the insecticides on the on the developmental period, survival rate, adult longevity, fecundity, and deformity rate were compared with those of the control. Compared with the control, cyantraniliprole and pymetrozine did not significantly affect the developmental period in the parental or F[sub.1] generation when applied at the nymphal stage at any concentration. Nonviable nymphs occurred in the F[sub.1] generation when both nymphs and adults were treated with spirotetramat and cyantraniliprole but not in the F[sub.2] generation. The age-specific maternity (lxmx) of A. gossypii treated with sublethal concentrations (LC[sub.10] , LC[sub.30] ) decreased with increasing concentration. Spirotetramat at the LC[sub.30] resulted in significant differences in all life table parameters (R[sub.0] , rm, λ, T, DT) compared with those of the control. Similarly, compared with that of the control (43.8), the net reproductive rate (R[sub.0] ) significantly decreased for all the insecticides except cyantraniliprole at the LC[sub.10] (37.5). Therefore, this study indicated that sublethal concentrations (over the LC[sub.30] ) of spirotetramat, cyantraniliprole, or pymetrozine might be useful for the density management