苏云金芽孢杆菌毒性研究

Toxicity Study of Bacillus thuringiensis

以菜青虫为试验材料,用苏云金芽孢杆菌浸泡过的小白菜饲喂菜青虫,提取菜青虫体内的伴孢晶体,通过生物测定法对苏云金芽孢杆菌的毒性进行研究,并对出发菌株进行紫外诱变筛选高毒性菌株。结果表明,苏云金芽孢杆菌毒性与伴孢晶体含量有关,伴孢晶体含量越多,毒力越高;紫外诱变16min时得到菌株B16,伴孢晶体含量比出发菌株提高8.2%,杀虫效率比出发菌株提高77%。该研究为苏云金芽孢杆菌生产高效率生物农药提供菌种。

Cabbage caterpillar were used as research materials in the experiment,which was fed cabbage caterpillars with cabbage soaked in Bacillus thuringiensis .Parasporal crystals from Pieris rapae was extracted,study on the toxicity of Bacillus thuringiensis by bioassay and screening of highly virulent strains by UV mutagenesis of the starting strains were done.The results showed that the toxicity of Bacillus thuringiensis was related to the content of spore crystals,the more the content of the accompanying spore crystal,the higher the virulence.The strain B16 obtained by UV mutagenesis at 16 min raised the content of parasporal crystals by 8.2% compared with the original strain,insecticidal efficiency raised by 77% compared to the original strain.The study provides strains for the production of high-efficiency biological pesticides by Bacillus thuringiensis.