中文摘要：

考察对小菜蛾具有杀虫活性和无杀虫活性的晶体蛋白二肽组成的差异．结果发现，对小菜蛾具有杀虫活性的晶体蛋白中，SG，LS，SN，NI，GS，SV，SL，TV，EF，NQ二肽分数较高；而对小菜蛾无杀虫活性的晶体蛋白中，AN，LQ，DA，AQ，TF，SY，EI，LE，PT，RA二肽分数较高，总体分数上存在差异最大的是S^＊型二肽．在此基础上，发展一种识别杀虫晶体蛋白（ICP）对小菜蛾杀虫活性的统计学方法，通过对两组共27条杀虫晶体蛋白进行有无杀虫活性的初步识别，该方法识别平均正确率分别是71．4％和100％．

英文摘要：

In this work, the dipeptide composition of crystal proteins with and without insecticidal activity against Plutella xylostella was systematically analyzed. We found that crystal proteins with insecticidal activity against Plutella xylostella contained more dipeptides such as SG, IS, SN, NI, GS, SV, SL, TV, EF and NQ, whereas less dipeptides such as AN,LQ,DA,AQ,TF,SY,EI,LE,PT and RA, and generally, S^＊ was the most different dipeptide. Based on this information, a statistical method for discriminating 27 crystal proteins with or without insecticidal activity against Plutella xylostella was developed and their accuracy was 71.4% and 100%, respectively.