Abstract: 【Objective】In order to clarify the control effect of cyantraniliprole on Athetis dissimilis, the effects of cyantraniliprole at low-lethal dosages on the growth, reproduction and nutritional utilization were studied after treated the 4th instar larvae of A. dissimilis. 【Method】The toxicity, as well as the nutritional utilization and the content of biochemical substances of cyantraniliprole on the 4th instar larvae of A. dissimilis were determined by using the method of artificial diet mixed with insecticides. The sublethal effects of cyantraniliprole on growth and development index: developmental time of larvae and pupae, mean longevity of adults, fecundity of females, the rate of pupation and eclosion were investigated. The feeding indices, such as the approximate digestibility (AD), the relative consumption rate (RCR), the relative growth rate (RGR), the efficiency of conversion of ingested food (ECI), and the efficiency of conversion of digested food (ECD) were determined at 72 h after treatment with different dosages of cyantraniliprole, and the contents of nutrients such as carbohydrates, proteins and lipids were also analyzed at 24, 48 and 72 h after cyantraniliprole treatment. 【Result】The result of bioassay showed that cyantraniliprole had high toxicity against 4th instar larvae of A. dissimilis, the LC₅₀ value was 0.66 µg·g^-1 artificial diet. The concentrations that caused 5% and 25% mortalities were 0.13 and 0.34 µg·g^-1 artificial diet, respectively. After being treated with cyantraniliprole, the durations of the 4th instar to 6th instar larvae stage were significantly prolonged 1.63, 1.75 and 5.48 days in the LC₅, LC₂₅ and LC₅₀ treatments, respectively. The period of pupae was prolonged while the period of adults was shortened, the pupation and eclosion rate were also declined. In addition, the pupal weight of female A. dissimilis in LC₅ (130.2 mg), LC₂₅ (127.8 mg) and LC₅₀ (127.5 mg) treatment groups was significantly reduced compared with the control group (146.7 mg). However, there was no significant difference in the pupal weight of male. The fecundity of female adults was also greatly decreased after treated with sublethal concentrations of cyantraniliprole, with 755.1, 558.8, 506.9 and 462.8 eggs/female, in the control, LC₅, LC₂₅, and LC₅₀ group, respectively. Meanwhile, the oviposition period was also significantly shortened, but cyantraniliprole did not have significant effect on the adult preoviposition period. compared with the control group, cyantraniliprole had markedly antifeedant effects, which significantly decreased the RGR, RCR, ECI and ECD of larvae. The amount of total carbohydrate in the 4th instar larvae of A. dissimilis in cyantraniliprole-treated groups decreased significantly compared with the control group in 24 h, similarly, from 48 h to 72 h. Meanwhile, the effects on the contents of proteins and lipids in the treatment groups were similar to carbohydrates. All these adversely affected the normal growth and development of A. dissimilis. 【Conclusion】Low-lethal dosages of cyantraniliprole can suppress the development and fecundity of A. dissimilis population, which is beneficial to the long-term control of A. dissimilis.

Key words: Athetis dissimilis, cyantraniliprole, development, fecundity, nutritional utilization