云南昭通苹果根癌病病原菌的鉴定

Identification of Pathogens of Apple Root Cancer in Zhaotong,Yunnan

为分离鉴定云南昭通苹果根癌病病原菌。笔者从云南昭通苹果园采得20株根部长有瘿瘤的苹果苗,将瘿瘤部分进行分离培养,得到20个菌株分离物,将得到的菌株针刺接种至番茄幼苗检测其致病性,对致病性菌株提取DNA,使用分子生物学方法进行鉴定,根据细菌通用引物以及细菌Vir C基因特异区段设计的特异引物进行PCR扩增、测序,经BLAST比对。结果表明:其中有3株能够引发典型的根癌症状,且3株致病菌均为根癌土壤杆菌。[结论]导致云南昭通苹果根癌病的病原菌为根癌土壤杆菌。

To isolate and identify the pathogens of Apple root cancers in Zhaotong,Yunnan.[Method]Twenty apple seedlings with gall nodules at root length were collected from an apple orchard in Zhaotong in Yunnan Province.The gall nodules were separated and cultured,and 20 isolates of strains were obtained.The obtained strains were inoculated with needles to tomato seedlings to detect their pathogenicity.DNA of the pathogenic strains were extracted and analyzed using molecular biology method.Universal primers for bacteria and specific primers designed for virC gene specific segment of bacteria were amplified by PCR.The obtained DNA fragmentswere sequenced and compared by BLAST.[Result]Three of them could cause typical root cancerous symptoms,and the three pathogenic bacteria were Agrobacterium tumefaciens.[Conclusion]The pathogen causing Apple root cancers in Zhaotong,Yunnan is A.tumefaciens.