小菜蛾(Plutella xylostella L.)为世界性害虫，全国各地蔬菜生产区均有为害，以南方各地发生为重。广东省是蔬菜种植大省，蔬菜种植面积近100万hm2，由于地处热带、亚热带地区，蔬菜复种指数高，气候条件非常适合小菜蛾的发生和为害。小菜蛾年发生世代多，为害重，导致用药次 Plutella xylostella L. is a worldwide pest and has been harmed by vegetable production areas throughout the country, taking place in all parts of the South. Guangdong Province is a major vegetable growing province with vegetable planting area of ​​nearly 1 million hm2. Due to the high level of multiple cropping index in the tropical and subtropical regions, climatic conditions are very suitable for the occurrence and damage of diamondback moth. Plutella xylostella occurs more than a generation, as heavy, leading to medication times