解淀粉芽胞杆菌B9601-Y2对大白菜软腐病防治效果研究

Control effects of Bacillus amyloliquefaciens B9601-Y2 on soft rot of Chinese cabbage

为了明确解淀粉芽胞杆菌B9601-Y2(Y2)对大白菜软腐病的防治效果,本研究通过平板对峙和离体生防试验评估了B9601-Y2对软腐病的生防潜力,同时采用绿色荧光蛋白标记菌株Y2-gfp,测定其在大白菜植株内的定殖能力,在温室内研究了B9601-Y2对大白菜软腐病的防治和增产效果。结果表明,B9601-Y2在LB平板和离体植物组织上均能有效地抑制软腐病原菌的生长;淋灌Y2-gfp发酵液后,标记菌在大白菜根际、根、茎、叶等组织内的种群数量呈现出“先上升后下降最后趋于平稳”的趋势,最终稳定在约103cfu/g组织;温室防效试验结果表明,移栽生防苗后淋灌Y2菌悬液防治效果最佳,为62.23%,仅移栽生防苗与移栽普通苗后淋灌Y2菌悬液防效分别为28.87%与49.48%,大白菜产量分别增加了146.58%、47.52%及109.37%。研究结果表明解淀粉芽胞杆菌B9601-Y2能够有效防控大白菜软腐病。

To determine the control effect of Bacillus amyloliquefaciens B9601-Y2(Y2)against Chinese cabbage soft rot caused by Pectobacterium carotovorum subsp.carotovorum(Pcc),it was evaluated by the plate confrontation and biocontrol activity tests in vitro.Its colonization ability was tested in Chinese cabbage by drenching Y2-gfp suspension,a gfp-labeled Y2 strain,and soft rot control and yield recovery effects were also studied in the greenhouse.The results indicated that the growth of Pcc on LB agar plate and in plant tissue in vitro was effectively inhibited by Y2.Y2 population in the rhizosphere,root,stem and leaf of cabbage after drenching showed a trend of rising first,decreasing and then leveling off;finally the colonization density kept at 103cfu/g tissues.Moreover,the control effect of Y2 suspension drenching on Y2-cultured seedlings was 62.23%,while the control effect on Y2-cultured seedlings without Y2 suspension drenching was 28.87%and the control effect of Y2 suspension drenching on the seedlings without Y2-substrate was 49.48%.Meanwhile,the three treatments increased the fresh weight of cabbage by 146.58%,47.52%and 109.37%,respectively.This study suggested that Y2 could efficiently control soft rot of Chinese cabbage.