玉米大斑病生防菌的筛选、鉴定及应用研究

Biocontrol Bacteria Against Northern Corn Leaf Blight:Screening,Identification and Application

为了从生物途径探索有效控制大斑病在玉米生产带来的危害,本试验以玉米大斑病菌(Setosphaeria turcica)为目标菌株,采用对峙法和盆栽接种试验获取生防菌,并测定其盆栽防治效果。结果表明:从128株玉米内生细菌获得1株对玉米大斑病菌拮抗效果最佳的菌株,最长半径与最短半径比值为2.9。从玉米内部分离到的内生生防细菌YD7对大斑病菌具有较强拮抗效果。根据YD7菌株形态培养特征、生理生化特征及16S rDNA序列分析结果鉴定为解淀粉芽孢杆菌。经过2次盆栽测定,YD7对玉米大斑病防治效果分别为78.2%和77.8%。综合表明,YD7防治玉米大斑病具有很好的开发前景。

In order to explore the biological way to effectively control the damage of northern corn leaf blight in corn production,Setosphaeria turcica was used as the targeted strain.The biocontrol bacteria were obtained using confrontation method and pot inoculation test.The control effect of pot inoculation test was determined.The results showed that one strain with the best antagonistic effect was obtained from 128 strains of endophytic bacteria.The ratio of the longest radius to the shortest radius was 2.9.The biocontrol bacteria YD7 was screened from corn endophytic bacteria and it had relatively strong antagonistic effect against S.turcica.According to the morphological,physiology-biochemical characteristics and 16S rDNA sequence analysis,YD7 was identified as Bacillus amyloliquefaciens.By two potted experiments,the control effects of YD7 were 78.2% and 77.8%,respectively.Thus,YD7 has well developing prospect on controlling northern corn leaf blight.