对甜菜夜蛾高毒力Bt新菌株的PCR-RFLP分析及生物活性测定

PCR-RFLP analysis of new Bt strains against Spodoptera exigua and toxicity activity analysing

利用PCR-RFLP对Bt.新菌株cyz-13,T4-3的基因型进行分析。结果表明,cyz-13含有cry1Aa,cry1Ac,cry1Bc,cry2Ab4种基因型,其中cyz-13菌株的PCR产物的酶切片断类型不同于已知的基因类型;T4-3菌株含有cry1Aa,cry1Ac,cry1Ag,cry2Ac,cry1Ia5种基因型。室内生测结果显示,两菌株对甜菜夜蛾、粘虫、棉铃虫、玉米螟均具有高毒力,好于H D-1标准菌株。两菌株的发酵液均有杀虫活性,二者上清的杀虫因子不同。

PCR-RFLP was used for detecting the cry-type genes from new Bacillus thuringiensis strains, T4-3 and cyz-13. The results showed that there was five cry-type genes including cry1Aa, cry1Ac, cry1Ag, cry2Ac and cry1Ia in Bt T4-3 strains; Three types of gene of cry1Ac cry1Bc cry2Ab were identified in Bt cyz-13 strain, The result of restriction enzyme analysis showed that the fragments from cyz-13 strain was different from all of published genes the bioassay showed that there was more infectivity with T4-3 or cyz-13 compated to standared strain, HD-1.