马铃薯软腐病菌室内药剂及拮抗细菌筛选

Screening of the agents and antagonistic bacteria to Pectobacterium carotovorum subsp. brasiliense

由Pectobacterium carotovorum subsp. brasiliense(Pcb)引起的马铃薯细菌性软腐病是马铃薯重要病害之一,在我国马铃薯产区普遍发生,危害严重,其化学防治和生物防治研究和应用较少。以Pcb为指示菌,选择9种常用的细菌药剂,通过室内平板试验,筛选出对Pcb具有抑菌作用的4种药剂,抑菌效果依次为万胜清(20%溴菌腈·5%壬菌铜)、克菌康(3%中生菌素)、辛菌胺醋酸盐和金霉唑(1.5%噻霉酮);进一步从土壤中分离并获得对Pcb有拮抗作用的5个拮抗细菌RFjk1～RFjk5,它们分别与菠萝泛生菌(Pantoea ananatis)、粘质沙雷氏菌(Serratia marcescens)、变形假单胞菌(Pseudomonas plecoglossicida)及松鼠葡萄球菌(Staphylococcus sciuri)的16SrDNA序列相似性在99%以上,鉴定为粘质沙雷氏菌的拮抗细菌RFjk2,显示出潜在应用前景,可望为马铃薯细菌性软腐病的化学防治和生物防治奠定基础。

Bacterial soft rot of potato,caused by Pectobacterium carotovorum subsp.brasiliense(Pcb),is one of the most important diseases in the world.It is widespread and serious in potato producing areas in China and usually causes huge economic losses.Little investigation has been done on applications of chemical and biological control to the disease in China.In this study,Pcb was used as the indicator bacteria against nine kinds of chemical agents to develop effective chemicals on the plate experiment.Four kinds of chemicals,including Wanshengqing(20%bromothalonil+5%cuppric nonyl phenolsulfonate),gramcazole(3%zhongshengmycin),octyl amine acetate and Kecocon(1.5%thiazolone)have acquired good antibacterial effect on Pcb respectively.Further investigation showed that five antagonistic bacterial strains which were isolated from soils have good bacteriostatic activities to Pcb and were preliminarily identified as Pantoea ananatis,Serratia marcescens,Pseudomonas plecoglossicida and Staphylococcus sciuri by 16S rDNA,respectively.The antagonistic bacterial strain of RFjk2 which was identified as Serratia marcescens showed a potential application on biological control of potato soft rot.The results would lay the foundation for the chemical and biological control to bacterial soft rot of potato.