枯草芽孢杆菌B215生物学特性及对香蕉枯萎病的生防效果评价

Test of the Biocontrol Effect of Bacillus subtilis B215 on Banana Vasicular Wilt

在室内测定菌株B215对香蕉枯萎病菌菌丝生长和孢子萌发都有良好抑制效果的基础上,优化拮抗菌株的最佳培养条件为:在NA培养基上,装液量为50mL/500mL,最适初始pH值为7.0～7.5,初始接菌量为1%,培养温度为28℃,以便更好地应用于田间试验。以此培养条件为依据,开展拮抗菌株的盆栽小苗实验,选用正交试验L8(27)设计,得出菌株B215对香蕉枯萎病菌的最佳防效组合为:在小苗定植前,用活菌培养液750mL/株浸根,可以降低小区香蕉枯萎病发病率。进一步试验验证结果显示:盆栽试验B215对Foc的防效为62.95%。

The strain of Bacillus subtilis B215 with good antagonisticity against Fusarium oxysporum f.sp.cubense was tested by the dual culture and conidial germination meathod.The results showed that optimum fermentation condition for B215 was to be inoculated for 48 h at 28 ℃ in NA medium （pH7.0-7.5）,and the optimal inoculum and medium for the growth strain B215 was 1% and 50mL/500 mL,respectively.According to the residual number of Foc spores in the soil,the orthogonal design analysis was conducted to test the effect of antagonistic B215 on Foc in the greenhouse.the results showed the optimal combination was root dipping by culture liquid of strains （750 mL per line） before seedling colonization.The control effects of the strain B215 on the Foc was 62.95%.