小菜蛾是蔬菜的一种主要害虫。为有效地防治该虫 ,减小农药残留和对环境污染 ,筛选高效、低毒、低残留的生物农药很有必要。作者于 1 999～2 0 0 0年用无公害农药 Bt悬浮剂 40 0 0 IU/μl对小菜蛾进行药效试验。现将结果整理如下。1　材料与方法试验在武昌南湖农场菜地进行。菜 Plutella xylostella is a major pest of vegetables. In order to effectively control the insects, reduce pesticide residues and environmental pollution, screening high efficiency, low toxicity, low residual bio-pesticides is necessary. The author from 1999 to 2000 with pollution-free pesticide Bt suspension 40 0 ​​0 IU / μl on the diamondback moth efficacy test. The results are now organized as follows. 1 Materials and Methods The experiment was conducted in the vegetable farm of Nanhu Farm in Wuchang. dish