【摘要】 从自然死亡的玉米螟幼虫体内分离获得一株对玉米螟高毒的苏云金芽孢杆菌,编号为HB-3。该菌株产生菱形和方形两种晶体蛋白。纯化晶体及孢晶混合物的毒力测定结果表明,该菌株对玉米螟具有较高毒力,LC50分别为5.82μg/mL和5.94μg/mL,对尖音库蚊也有一定毒力,LC50分别为16.59μg/mL和17.50μg/mL。生理生化特性研究结果表明,HB-3与已知的蜡螟亚种(Bacillus thuringiensissubsp.galleriae)基本一致,血清型为H5ab。晶体蛋白的SDS-PAGE分析表明,HB-3菌株晶体蛋白至少由分子量为133 kDa、65 kDa4、5 kDa和23 kDa的4种多肽组成。更多还原

【Abstract】 A new strain of Bacillus thuringiensis numbered as HB-3 that was highly toxic to Ostrinia furnacalis Guenee was isolated from the dead larvae of Ostrinia furnacalis Guenee.It produced bipyramidlike and squareness-like crystals.Bioassay results showed that its crystal and the mixture of spore and parasporal crystal possessed very high toxicity to Ostrinia furnacalis Guenee,with LC₅₀ as 5.82 μg/mL and 5.94 μg/mL,respectively.Meanwhile,they also had steady toxicity to Culex pipiens Linnaeus,with LC₅₀ as 16.59 μg/mL and 17.50 μg/mL,respectively.It is accordant with B.thuringiensis subsp.galleriae in biochemical reactions,and its serotype belongs to H5ab.Its parasporal crystal consists of four kinds of proteins,i.e.133 kDa,65 kDa,45 kDa and 23 kDa as separated by SDS-PAGE.更多还原