华南小菜蛾田间种群对氯虫苯甲酰胺已产生严重抗性

2009—2011年在广东连州、惠州、佛山、广州和广西柳州、江西信丰等多个华南区主要菜场开展小菜蛾对氯虫苯甲酰胺的抗药性监测。结果发现,与室内敏感种群的敏感基线相比(LC50=0.13 mg/L),各监测点在2009年秋季均为敏感水平,2010年秋季部分地区出现敏感性下降和低水平抗性,而2011年春季除了监测到敏感性下降和低水平抗性外,还发现个别监测点产生中等水平抗性,抗性上升趋势明显。随后,在广州增城菜区监测到一例对氯虫苯甲酰胺产生极高水平抗性的小菜蛾田间种群,其当代和F1代虫源的LC50值分别为78.78、59.14 mg/L,抗性倍数分别为606.00和454.92,达极高抗性水平。分析小菜蛾对氯虫苯甲酰胺产生抗药性的关键因素,认为过度依赖该药、随意提高施用剂量、不合理混配、连年连片单一种植模式等可能是有利于抗药性发展的关键因素。

Found a field population of diamondback moth, Plutella xylostella (L.),with high-level resistance to chlorantraniliprole in South China

Resistance monitoring for diamondback moth on chlorantraniliprole was conducted by Institute of Plant Protection,Guangdong Academy of Agricultural Sciences from 2009 to 2011 in South China,including Lianzhou﹑Huizhou﹑Foshan and Guangzhou cities in Guangdong province,Liuzhou city in Guangxi province and Xinfeng city in Jiangxi province.The results showed that,compared with toxicity baseline of susceptible population which was reared in lab more than six years(LC50=0.13 mg/L),all of the field populations showed high sensitivity to chlorantraniliprole in 2009.However,one field population showed sensitivity decline and another field population even showed a low-level resistance in 2010.In 2011,medium-level resistance also tested additional.It is means that the development of diamondback resistance to chlorantraniliprole was raised significantly.Then,a field population in Zengchen country,Guangzhou city was collected and lab testing showed that had high-level resistance,the LC50 of previous generation larvae and F1 generation larvae was 78.78 mg/L(resistance ratio was 606.00) and 59.14 mg/L(resistance index was 454.92) respectively.Analysis the causal factors that leading to the development of diamondback resistance to chlorantraniliprole.Over-dependency on chlorantraniliprole,over dosing,lack of a sound rotation program and continuous plantings maybe are some of the key factors leading to insect resistance.