对夜蛾科幼虫高毒力的苏云金芽孢杆菌菌株及其晶体蛋白特性

BT STRAINS HIGHLY TOXIC TO NOCTUIDAE LARVAE WITH NOTES ON THE CHARACTERISTICS OF THEIR CRYSTALLINE PROTEIN

本文对自德国土壤中分离的８株苏云金芽孢杆菌进行毒力测定和晶体蛋白特性的研究。生物测定结果表明，８株Ｂｔ中除Ｓ２１－１、Ｓ２１－１３对甜菜夜蛾无毒性外，对夜蛾科的４种供试昆虫均有很高的毒效，４８小时校正死亡率高达８０％～１００％；扫描电镜观察和ＳＤＳ－ＰＡＧＥ晶体蛋白电泳结果可知，Ｓ１１－６和Ｓ２１－１３２个菌株只有一种菱形晶体和一条相应的１３５ＫＤａ主带，其余６个菌株均有菱形和方形两种晶体，以及两条相应的１３５ＫＤａ和６５ＫＤａ主带。另对晶体的特性与其毒力的关系进行了讨论。

The toxicity of eight Bacillus thuringiensis strains isolated from German soil and the character of crystal protein was reported in this paper. Bioassay results showed that all the Bt strains possessed very high toxicity to four test insects of Noctuidae. The corrected mortality at 48h reached 80% 100%. Scanning electromicroscopic observation and the pattern of SDS PAGE protein electrophoresis indicated that S 11 6 and S 21 13 strains had only one kind of bipyramidal crystal and one 135KDa main band, the other six strains had both bipyramidal and square crystal and 135KDa and 65KDa main bands. Relation of crystal protein character to its toxicity was also discussed.