烟草疫霉拮抗菌筛选、鉴定及发酵条件研究

从毕节8个县市种植烟草的田地采集土壤样品122份，筛选出5 株对烟草疫霉有较强拮抗作用的菌株。其中一菌株抑菌活性最强且拮抗效果稳定，综合形态学、生理生化及分子生物学实验可以将其鉴定为蜡样芽孢杆菌（Bacillus cereus ），记为1205。该菌株现已保藏于中国典型培养物保藏中心，保藏编号为CCTCC NO.M2012382。经过对1205菌株的液体摇瓶发酵条件研究，结果表明，1205菌株摇瓶振荡的最适培养条件：培养基为NYBD，接种量为1%，初始pH值为6.0，培养温度为28℃，装液量为20mL/100mL，摇床转速为160r/min，培养时间为28h。

Identification and fermentation of antagonistic bacterium against Phytophthora nicotianae

5 strains that had strong antagonistic effect on Phytophthora nicotianae were screened from 122 soil samples that came from tobacco fields in Bijie.One strain showed the strongest antibacterial activity and stability of the antagonistic effect and it was identified as Bacillus cereus which was named 1205 based on morphology,physiology and biochemistry and molecular biology experiment.The strain was preserved in typical culture preservation centre in China,and the accession number was CCTCC NO.M2012382.Through the study on the fermentation conditions of strain 1205,the optimum culture conditions were as follows：medium NYBD,inoculation quantity 1％,initial pH 6,temperature 28℃,liquid volume 20ml/100ml,rotate speed 160r/min,incubation time 28h.