棉铃虫对溴氰菊酯、三氟氯氰菊酯及其复配剂的抗性趋势与交互抗性

STUDIES ON THE LABORATORY DEVELOPMENT OF RESISTANCE AND CROSS-RESISTANCE OF COTTON BOLLWORM TO DELTAMETHRIN, CYHALOTHRIN AND A MIXTURE CONTAINED CYHALOTHRIN

在70％的高选择压下,分别用溴氰菊酯、三氟氯氰菊酯和凯明2号(50％辛硫磷·甲基对硫磷·三氟氯氰乳油,即含三氟氯氰菊酯的复配药剂)对室内饲养了12代未经农药处理的棉铃虫Helicoverpa armigera(H(?)bner)敏感品系进行了抗性筛选。结果,经连续筛选至第12代的LD_(50)值与筛选前第1代的LD_(50)值比较,抗溴氰菊酯种群对溴氰菊酯的抗性为136.7倍,属高抗水平;抗三氟氯氰菊酯种群对三氟氯氰菊酯的抗性为9.5倍,抗凯明2号种群对凯明2号的抗性为3.4倍,均属低抗水平。用8种常用杀虫剂分别对这3个种群在停止上述杀虫剂筛选2代后进行了交互抗性分析。结果表明,3个种群平均对8种杀虫剂的抗性倍数中,对溴氰菊酯、氰戊菊酯、灭多威的抗性极显著高于其余5种杀虫剂;3个种群的平均抗性倍数之间差异极显著,顺序依次为抗溴氰菊酯种群>抗三氟氯氰菊酯种群>抗凯明2号种群;以平均抗性倍数表示的抗性种群与杀虫剂的交互作用有以下几个结果:①高抗溴氰菊酯的种群对氰戊菊酯和灭多威有极显著的交互抗性,但对三氟氯氰菊酯和凯明2号仍反应敏感。②抗三氟氯氰菊酯和抗凯明2号的2个种群对溴氰菊酯有极显著的交互抗性;抗三氟氯氰菊酯种群对灭多威和氰戊菊酯有一定抗性,抗凯明2号种群对硫丹有一定抗性。

Systematic screenings were carried out under 70% selective pressure in labo-ratory for the resistant populations of cotton bollworm (CBM) Helicoverpa armigera (Hubner) separately to deltamethrin, cyhalothrin and Kaiming 2 (a mixture contained cyhalothrin ), initially with a susceptible CBM strain without pesticide treatment through a whole 12 rearing generations. The results showed that the ratios of LD50s of CBM populations resistant to these insecticides, after successive screenings for 12 generations separately with their own insecticides,to the LD50S of 1st generation themselves were 136. 7-,9. 5- and 3. 4-fold, respectively, indicated that the deltamethrin population was already highly resistant to deltamethrin ,cyhalothrin population was lowly resistant to cyhalothrin and Kaiming 2 population was still basically susceptible to Kaiming 2. The results of mean resistance values of three populations separately to eight insecticides showed that the resistance to deltamethrin, fenvalerate and methomyl were significantly higher than those to the other five insecticides. There were highly significant differences among the mean resistance values of three populations to whole insecticides, i. e. deltamethrin population>cyhalothrin population>Kaiming 2 population. The prominent interactions among CBM population and insecticides were as follows: (1)There were highly significant cross-resistances of deltamethrin population to fenvalerate and methomyl, while this population was still sensitive to cyhalothrin and Kaiming 2. (2) There were highly significant cross-resistances of cyhalothrin population and Kaiming 2 population to deltamethrin; and it is noteworthy that somewhat resistances had occurred in cyhalothrin population to methomyl and fenvalerate and Kaiming 2 population to endsulfan.