甜菜夜蛾 Laphygma exigua Hübner 以前为害蔬菜报道甚少,近几年来发生逐渐上升。据浙江、江西、湖北、湖南、四川、贵州、深圳等省、市的调查报道,该虫危害严重,尤其是7—9月夏季高温期,为害十分突出。蕹菜、苋菜、豇豆、瓜类及十字花科蔬菜等受害最重,暴发时可将叶片吃光,损失极大。作者(1990)、朱树勋等(1990)曾报道该虫抗药性突出、难于防治,已成为我国长江流域及其以南省、市的重要蔬菜害虫。就我市而言,1990年7—9月甜菜夜蛾暴发成灾,常规防治难以见效,农药使用曾一度失控,造成农药残留中 Beet armyworm Laphygma exigua Hübner Reported little vegetables before, in recent years, the gradual rise. According to the investigation reports of Zhejiang, Jiangxi, Hubei, Hunan, Sichuan, Guizhou and Shenzhen provinces and cities, the pest is seriously endangered, especially during the summer heat period from July to September. Bracken vegetables, amaranth, cowpea, melons and cruciferous vegetables and other victims of the most serious, when the leaves can be eaten out of light, great loss. The authors (1990) and Zhu Shu-xun et al. (1990) reported that the insecticide is prominent and difficult to control and has become an important vegetable pest in the Yangtze River valley and its southern provinces and cities in China. In our city, the outbreak of beet armyworm from July to September in 1990 made the conventional control difficult to be effective. The use of pesticide once ran out of control, resulting in pesticide residue