枯草芽孢杆菌BC80-6发酵条件的优化及对烟草根黑腐病的控病效果

Optimization of fermentation conditions for Bacillus subtilis BC80-6 and its control on Thielaviopsis basicola of tobacco

探究了3种枯草芽孢杆菌BC80-6处理液对烟草根黑腐病菌菌丝生长、孢子萌发的抑制作用,对其发酵条件进行了优化,并开展田间控病防效试验。结果表明:10^(-1)倍枯草芽孢杆菌BC80-6的活菌液对烟草根黑腐病菌菌丝生长和孢子萌发的抑制效果最好,抑制率分别为93.2%、95.3%。通过单因素试验及正交试验对菌株BC80-6培养基的配方进行优化,确定培养基的最佳配方为蔗糖1.5%、酵母浸出物0.5%、硫酸镁0.06%(质量体积比)。最佳发酵条件:发酵温度28℃、时间24 h、初始pH 6.5、摇床转速180 r/min、接种量5%、装液量40 mL(250 mL三角瓶)。枯草芽孢杆菌活菌液对烟草根黑腐病的田间防效为88.19%。

To clarify the effects of Bacillus subtilis BC80-6 on Thielaviopsis basicola,the inhibitory effects of three treatment solutions of B.subtilis BC80-6 on the mycelial growth and spore germination of T.basicola were investigated.BC80-6 fermentation conditions were optimized and field control experiments were carried out.The results showed that 10-1 times living bacteria solution of B.subtilis BC80-6 had the best inhibitory effects on the mycelial growth and spore germination of B.subtilis with the inhibition rates of 93.2%and 95.3%,respectively.Via a single factor test and an orthogonal experiment,the optimum BC80-6 medium was 1.5%sucrose,0.5%yeast extract and 0.06%magnesium sulfate(mass/volume ratio).The best fermentation condition was fermentation temperature 28℃,time 24 h,initial pH 6.5,rotation speed 180 r/min,inoculation amount 5%(v/v)and medium volume 40 mL in 250 mL triangular bottle.The field control effect of living bacteria solution of B.subtilis on tobacco root black rot was 88.19%.