苏云金芽胞杆菌GS8菌株的生物学特性及其cry基因型鉴定

Biological Characteristics of Bacillus thuringiensis IsolateGS8 and Identification of its cry-type Genes

摘要: 采用桑叶浸渍法和饲料表面覆盖法测定发现,从土壤中分离的一株苏云金芽胞杆菌菌株GS8对家蚕Bombyx mori、甜菜夜蛾Spodoptera exigua和棉铃虫Helicoverpa armigera初孵幼虫均表现出较高的杀虫活性,经形态学和生理生化反应鉴定该菌株为东北亚种(Bacillus thuringiensis subsp.tohokuensis)。聚丙烯酰胺凝胶电泳(SDS-PAGE)分析结果表明,GS8菌株的杀虫蛋白晶体主要由分子质量为130、81和60 kDa的蛋白组成。聚合酶链反应-限制性片段长度多态性(PCR-RFLP)鉴定结果显示,GS8菌株含有 cry1Aa、cry1Ab、cry1Ib、cry2Ab和cry9Ba 等基因。

Abstract: A modified diet overlay assay method and immersed mulberry leaf assay method were employed to test the susceptibility of neonates to a novel strain of Bacillus thuringiensis GS8,isolated from soil samples in China.The isolate GS8 showed high toxicity against neonates of Bombyx mori,Spodoptera exigua and Helicoverpa armigera.Morphological characteristics and physiological and biochemical test indicated that isolate GS8 was Bacillus thuringiensis subsp.tohokuensis.SDS-polyacrylamide gel electrophoresis revealed that 130,81 and 60 kDa proteins were the major components of crystal from GS8.PCR-RFLP revealed that cry1Aa,cry1Ab,cry1Ib,cry2Ab and cry9Ba genes were presented in the isolate GS8.