韩国土壤中苏云金芽孢杆菌菌株的分离和鉴定

Isolation and Identification of Bacillus thuringensis from Soil of Korea

从韩国不同地区采集的 6 2 0个土壤样品中分离出 6 7株苏云金芽孢杆菌 ,分属于 1 0种不同的血清型 .毒力测定结果表明 ,在 6 7株分离株中 ,35 .82 %的菌株对鳞翅目昆虫具有生物活性 ,2 2 .39%的菌株对双翅目昆虫有毒 ,32 .84%的菌株对鳞翅目和双翅目昆虫都具有杀虫活性 ,8.95 %的菌株为没有杀虫活性的无毒菌株 .其中对鳞翅目昆虫有毒的菌株产生典型的双金字塔形伴孢晶体 ,对双翅目昆虫有毒的菌株和无毒菌株都产生球形伴孢晶体 ,而对鳞翅目和双翅目都有毒的菌株产生双金字塔形或球形伴孢晶体 .用对 cry ,cry ,cry ,cry 和 cry 基因特异性引物作 PCR分析的结果表明 ,cry C基因占优势 ,其次为 cry A (b)和 cry A基因 ,但无 cry G,cry ,cry C和cry

A total of 67 strains of Bacillus thuringiensis were isolated from soils of various regions in Korea.Serological tests show that B.thuringiensis bacteria strains represent 10H serotypes.In toxicity tests,35.82% of all bacteria strains are toxic to Lepidoptera,22.3% are toxic to diptera, 32.8% are Lepidopteran /dipteran active bacteria strains and 8.95% were non toxic bacteria strains.All Lepidopteran active bacteria strains produce typical bipyramidal inclusions,and the remainder,which belongs to dipteran active and non toxic bacteria strains,are spherical in shape,while the lepidopteran/diptera active islolates produce bipyramidal or spherical inclusions.PCR analysis using cryⅠ,Ⅱ,Ⅲ,ⅣandⅤgene specific primers show that the frequency of the cryⅠC gene (21.83 %) predominate,followed by the cryⅠA(b) (19.01%) and cryⅡA genes (15.49 %);but cryⅠG,cryⅢ,cryⅣC and cryⅤ genes are not detected.