Effect of chlorantraniliprole and emamectin benzoate oil toxicity and detoxification enzymes activity in Spodoptera frugiperda larva.
To clarify the toxicity and detoxification mechanism of chlorantraniliprole and ematnectin benzoate to Spodoptera frugiperda, the LC10, LC20 and LC50 of two insecticides against third instar larvae were determined by leaf impregnation method, and the effeth on the activities of the three main detoxifying enzymes carboxylesterase (CarE), glutathione-S-transferase (GST), cytOchrome P450 (CYP450) of larvae were explored by two pesticides with the sublethal dose (LC20). The results showed that the toxicity of methyvitamin was higher to larvae, and the values of LC10, LC20 and LC50 were 0.005, 0.007 and 0.013 mg/L at 48 h, respectively. During 72 hours of treatment with two pesticides, the activity of three enzymes of larvae showed different dynamic changes. CarE activity was first induced and then inhibited by chlorantraniliprole, and CarE activity was the highest (36.75 U/mg) at 24 h. CarE activity was first inhibited and then induced by emamectin benzoate, arid CarE activity was the highest (42.44 U/mg) at 72 h. The changes of GST activity of the two pesticides were consistent within 72 h, showing the rule of "induction-inhibition-induction". The activity of CYP450 in larvae treated with chlorantraniliprole was not significantly different from that of the control, and the activity of CYP450 in larvae treated with emamectin benzoate for 36, 48 and 72 hours was significantly lower than that of the control.