A total of 61 bacterial strains was isolated in soils from Chittoor and Kadapa districts of Andhra Pradesh, India using sodium acetate selection method and preliminarily identified as Bacillus thuringiensis based on Gram's staining, endospore staining and crystal protein study. These strains were tested against the insect, Spodoptera litura under laboratory conditions and found 18 strains with ≥ 50% insect mortality. Further, these eighteen strains were analyzed for the insecticidal crystal protein composition with fourteen cry specific primers. The results indicated that, among all 14 cry genes, cry1I was the observed in 11 strains, followed by cry1Aa in 10 strains. At the same time a strain, F493 collected from Talakona area identified an effective against S. litura with 100 per cent larval death and which was also identified with 8 different crystal protein encoding genes (cry1Aa, cry1Ac, cry1Fa1, cry1I, cry2, cry2A(a)1, cry8, cry9Ca1).

中文翻译：

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印度安得拉邦土壤苏云金芽孢杆菌cry基因的多样性

根据醋酸钠筛选方法，从印度安得拉邦Chittoor和Kadapa地区的土壤中分离出总共61株细菌，并根据革兰氏染色，内生孢子染色和结晶蛋白研究初步鉴定为苏云金芽孢杆菌。在实验室条件下对这些菌株进行了抗昆虫斜纹夜蛾的测试，发现了18株昆虫死亡率≥50％的菌株。此外，用十四个cry特异性引物分析了这十八个菌株的杀虫晶体蛋白组成。结果表明，在所有14个cry基因中，在11个菌株中观察到cry1I，然后在10个菌株中观察到cry1Aa。同时，从塔拉科纳（Talakona）地区收集的F493菌株鉴定出抗S的有效剂。