大葱叶际生防细菌筛选及对紫斑病防效研究

Screening for biocontrol bacteria against Alternaria porri from phyllosphere of welsh onion

为了挖掘大葱紫斑病生防资源,研究采用培养法从大葱叶际分离细菌,然后用对峙培养法筛选大葱紫斑病菌生防细菌.结果表明:大葱叶际细菌群落中嗜甲基单胞菌、鞘氨醇单胞菌属、微杆菌属、假单胞菌属于优势细菌类群.从中筛选出1株对大葱紫斑病菌具有较好拮抗活性的菌株X85,经形态特征和16S rDNA序列鉴定为亚麻假单胞菌.田间试验表明该菌对大葱紫斑病的防效为63.1%.该研究为后续开发大葱紫斑病生物防治奠定基础.

To develop biocontrol resource against Alternaria porri,bacteria were isolated from phyllosphere of welsh onion by cultured method and screened for biocontrol bacteria using confrontation culture.The result showed that Methylobacterium,Sphingomonas,Microbacterium and Pseudomonas were the dominant groups in the community of phyllosphere.One strain bacterium with high activity of against A.porri was obtained from the phyllosphere bacteria group.According to morphological characteristics and 16S rDNA sequence,the bacterium was identified as Pseudomonas lini.The control efficiency of P.lini against Alternaria leaf spot was 63.1%by field trial.This will lay the foundation for the further development of biological control of the disease.