双酰胺类杀虫剂对棉铃虫和松毛虫赤眼蜂的选择毒力

为了指导棉铃虫防控中化学杀虫剂和天敌昆虫协调使用,本文采用浸叶法和玻管药膜法测定了4种双酰胺类杀虫剂对棉铃虫3龄幼虫和松毛虫赤眼蜂成蜂的毒力.结果表明,供试双酰胺类杀虫剂中氯虫苯甲酰胺、氟苯虫酰胺和氟氰虫酰胺对棉铃虫幼虫表现出了较高的毒力水平(LC50分别为0.2882、0.3894、0.8609 mg/L),稍低于对照药剂甲氨基阿维菌素苯甲酸盐(简称:甲维盐)(LC50为0.06493 mg/L);而溴氰虫酰胺对棉铃虫的毒力(LC50为3.7638 mg/L)明显低于甲维盐.从对天敌昆虫安全性来看,氯虫苯甲酰胺、氟苯虫酰胺和氟氰虫酰胺对松毛虫赤眼蜂的毒性(LC50分别为1.0060、0.9933、1.1541 mg/L)明显低于甲维盐(其LC50为0.1646 mg/L),表现出了较高的安全性;但是,溴氰虫酰胺对松毛虫赤眼蜂毒性较高(LC50为0.4952 mg/L),安全性较差.本研究将为棉铃虫防控中药剂与天敌协调使用提供依据.

Selective toxicity of diamide insecticides to Helicoverpa armigera and Trichogramma dendrolimi

This paper aims to coordinate the use of chemical insecticides and natural enemy insects to guide the control of crops cotton bollworm. The toxicities of four diamide insecticides to 3rd instar larvae of cotton bollworm and the adults of Trichogramma dendrolimi were determined by using leaf-dip method and glass tube membrane method respectively. The results showed that chlorantraniliprole (0.2882 mg/L, LC50 value which is the same as below), flubendiamide (0.3894 mg/L) and tetraniliprole (0.8609 mg/L) all showed high toxic level to cotton bollworm, although they are lower than the toxicity of emamectin benzoate (0.06493 mg/L). However, the toxicity of cyantraniliprole to cotton bollworm (3.7638 mg/L) was significantly lower than that of emamectin benzoate. The safety evaluation results showed that the toxicities of chlorantraniliprole, flubendiamide and tetraniliprole to T. dendrolimi were 1.0060 mg/L, 0.9933 mg/L and 1.1541 mg/L respectively. They are also significantly safer than emamectin benzoate (0.1646 mg/L) to T. dendrolimi. But cyantraniliprole showed higher toxicity (0.4952 mg/L) to the adults of T. dendrolimi. This study will lay a theoretical foundation for the coordination of effective insecticides and natural enemy for the control of cotton bollworm.