中文摘要：

利用几丁质平板法和几丁质酶基因特异引物PCR两种方法，对本室保藏的995株苏云金芽孢杆菌的几丁质酶及其基因进行了检测．结果显示所有被检测的菌株都可以在几丁质为唯一碳源的平板上生长．其中93．0％的菌株PCR检测阳性，54．1％的菌株可产生明显的水解圈．证明苏云金芽孢杆菌中几丁质酶普遍存在．通过研究发现Bt几丁质酶活力高低与其血清型及杀虫晶体蛋白基因的类型无相关性．同时对286个菌株进行了抑小麦赤霉菌实验，筛选出19株抑真菌效果较好的苏云金芽孢杆菌．

英文摘要：

By the whitish opaque hale and PCR methods, the distribution of chitinase and chitinase gene in 995 Bacillus thuringiensis strains were detected. The results showed that all the stains could grow on the plates containing chitin as only carbon source. Moreover, 93.0 % B. thuringiensis strains harbored chitinase gene and 54. 1% B. thuringiensis strains could form a whitish, opaque halo surrounding the growing colony. It suggested that the chitinase was widely produced in B. thuringiensis strains and the chitinase activity was not related with the H-antigen serotype and the kinds of ICPs gene. 286 B. thuringiensis stains were selected to test their antifungal potential against Fusarium graminearum and 19 strains with high activity were screened out.