小菜蛾对溴氰虫酰胺的敏感基线及抗药性现状

The sensitivity baseline and current insecticide resistance of Plutella xylostella to cyantraniliprole

应用药膜法测试了小菜蛾敏感种群对最新杀虫剂溴氰虫酰胺的敏感基线,比较了4个田间种群对溴氰虫酰胺和氯虫苯甲酰胺的抗性水平,首次发现并报道了小菜蛾溴氰虫酰胺抗性田间种群。研究结果表明,小菜蛾敏感种群对溴氰虫酰胺的LC50为0.54 mg/L;岑村、惠州和石井田间种群对溴氰虫酰胺的LC50分别为10.64 mg/L、37.72mg/L和21.92 mg/L,达到中抗水平,对氯虫苯甲酰胺的LC50分别为71.1 mg/L、63.73 mg/L和40.82 mg/L,为高抗种群;连州田间种群对溴氰虫酰胺的LC50为0.23 mg/L,处于敏感状态,对氯虫苯甲酰胺的LC50为0.98 mg/L,属低抗水平。小菜蛾田间种群对溴氰虫酰胺抗药性的发展趋势与氯虫苯甲酰胺一致。

Cyantraniliprole is the newest commercial insecticide from the anthranilic diamides.In the present work,the baseline susceptibility to cyantraniliprole for Plutella xylostella was surveyed from a susceptible strain（Roth） and four geographical populations sampled from Guangdong province,China,and the median lethal concentrations（LC50） were assayed by using the pesticide-membrane method.The sensitivity baseline of P.xylostella to cyantraniliprole was 0.54 mg/L,and the LC50 s of the Cencun,Huizhou and Shijing population from Guangdong province to cyantraniliprole were 10.64,37.72,21.92 mg/L,respectively,which were 19.55- to 69.85- fold higher than the LC50 of Roth.The LC50 of the three populations to chlorantraniliprole was 71.1,63.73,40.82 mg/L,respectively.However,the Lianzhou field population remains susceptibility to cyantraniliprole,LC50 was 0.23 mg/L.The result showed that middle level of resistance to cyantraniliprole had evolved in field populations from Guangdong province of Southern China,and the developing trend was consistent with chlorantraniliprole,so the farmers should be careful to use this insecticide.