从山西太谷、运城采集的油菜中分离得到40株植物内生细菌,经过初步筛选得到具有生防潜力的菌株yc8,经鉴定为环状芽孢杆菌(B.circulans)。采用正交试验设计对油菜内生细菌yc8进行营养配方和发酵条件的系统研究。通过yc8发酵液中细菌浓度、拮抗物质质量浓度和yc8发酵液对油菜菌核病[Sclerotinia sclerotio-rum(Lib.)de Bary]的抑菌作用综合评定,得到优化配方为:麦芽糖(30g/L)、牛肉膏(50g/L)、酵母粉(7g/L)、MnSO4(2g/L)、FeSO4(1g/L)、ZnSO4(2g/L)、CaSO4(2g/L)、CuSO4(2g/L)、K2HPO4(2g/L)、KAl(SO4)2(1g/L)、发酵温度28℃、装液量40%、摇床转数150r/min、发酵液pH=7.5,使环状芽孢杆菌在摇瓶发酵条件产生拮抗物质质量浓度达到为725.1μg/mL和对油菜菌核病茵的平板抑菌率达到85.3%。 40 plant endophytic bacteria were isolated from the rapeseed collected from Taigu and Yuncheng in Shanxi Province. After preliminary screening, the strain yc8 with potential of bio-control was identified and identified as B. circulans. Orthogonal experimental design of rape endophytic bacteria yc8 nutritional formula and fermentation conditions of the system. Through the comprehensive evaluation of bacteriostasis of yc8 fermentation broth, antagonistic substance concentration and yc8 fermentation broth against Sclerotinia sclerotio-rum (Lib.) De Bary, the optimized formula was: maltose (30g / L (2g / L), CaSO4 (2g / L), CuSO4 (2g / L), beef extract (50g / L), yeast extract L, K2HPO4, KAl (SO4) 2 (1g / L), fermentation temperature 28 ℃, liquid volume 40%, shaking speed 150r / min, fermentation broth pH = 7.5, The concentration of bacteriocin antagonist in shake flask fermentation reached 725.1μg / mL and the inhibitory rate against S. sclerotiorum reached 85.3%.