福建地区不结球白菜黑腐病病原菌的分离与初步鉴定

为鉴定福州地区不结球白菜黑腐病致病菌,以感染黑腐病的不结球白菜植株为材料进行了病原菌分离和鉴定。通过观察所分离病原菌的形态及接种试验发现其形态和发病症状与黑腐病的形态和发病症状相一致。以细菌通用引物16S对该病原菌进行16SrDNA的PCR扩增测序分析,发现该病原菌与野油菜黄单胞菌(Genbank:CP017308.1)16SrDNA序列同源性为99.8%。从接种病原菌植株中重新分离病原菌,其16SrDNA序列与之前接种菌株序列一致。以上结果初步证明分离的病原菌为不结球白菜黑腐病病原菌,且该病原菌为十字花科黑腐病野油菜黄单胞菌野油菜致病种。

Isolation and Preliminary Identification on Pathogen of Black Rot Disease on Non-heading Chinese Cabbages in Fuzhou

Pathogen that caused the black rot disease on non-heading Chinese cabbages in Fuzhou was investigated.Microbial samples were collected from the diseased plants for isolation.Based on the morphology and inoculation test,selected microorganisms were tested further.Their 16S rDNA were amplified by PCR with the universal primer 16S.The positive fragment was sequenced and analyzed against NCBI database.A 99.8％ homology was found between an isolated bacterium and Xanthomonas campestris pv.campestris (Genbank:CP017308.1).Subsequently,the 16S rDNA sequence of the strain from the infected cabbage was confirmed to be identical to that of the pathogen for the inoculation.It was,therefore,concluded that the isolated strain was indeed the pathogen that caused the black rot disease on the non-heading cabbages,and was preliminary identified as Xanthomonas campestris pv.campestris.