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Chlorantraniliprole and indoxacarb insecticides exhibit good efficiency for control lepidopteran pests. The current study is a comprehensive analysis of the effect of lethal and sublethal concentrations of these insecticides on Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) by using the leaf dipping technique. The LC 50 values ranged from 0.06 to 1.07 mg/L, and 0.005 to 0.81 mg/L for chlorantraniliprole and indoxacarb, respectively. Our results showed that the treatment of the 2nd instar larvae with LC 50 concentrations of these insecticides significantly increased the length of larval and pupal duration as well as pupal weight in most cases. While, no significant differences have been found in the percentage of hatchability except for LC 50 equivalent of indoxacarb. Female behavior regarding calling activity decreased by 50-60% following exposure to the LC 50 concentration of both insecticides. Gas chromatography analysis results showed that both insecticides lowered pheromone titer except at chlorantraniliprole LC 50 equivalent for (Z,E)-9,12-tetradecadien-l-ol acetate, and indoxacarb LC 10 equivalent for (Z)-9-tetradecenyl acetate. Additionally, the activity of mixed-function oxidases and glutathione S-transferase were elevated relative to control. The carboxylesterase activity significantly increased when assayed with both chlorantraniliprole concentrations and indoxacarb LC 10 equivalent. These results indicate that chlorantraniliprole and indoxacarb could be effective for S. littoralis control.

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The effect of synthetic Bom-PBAN was studied in vivo and in vitro. In B. mori, injection of 0. 01 ng/female induced bombykol production and maximal production was attained at 1 ng/female in vivo. Time-dependence studies revealed an optimum response after incubation for 90-120 min at a dose of 0. 5 ng/female. In vitro, sex pheromone production was induced in B. mori at 0. 5 ng PBAN/ 150, ul Grace's medium and in S. lituya at 2 ng/50 pJ concentrations. Pheromone production reached maximum at 10 ng/ 150, ad in B. mori and 15 ng/ 50 4a1 in S, lituya, respectively. In both species, optimal incubation time was 90-120 min in vitro. Induction of sex pheromone production in vitro clearly indicates that the target organ of PBAN action is the pheromone gland in B. mori and S. lituya. Since sex pheromone production was also induced by calcium ionophore in vitro, Ca2+ is likely to mediate the action of PBAN.