陇南核桃致病性成团泛菌的分离鉴定及其致病性研究

摘要

本研究拟从核桃病叶中分离并鉴定其致病菌，以便更好地实施科学防治。以组织分离法分离核桃病叶中的成团泛菌，之后以形态学方法对该病菌进行形态学鉴定，并通过细菌16 S rDNA 序列分析进行分子鉴定。结果表明，该病原为成团泛菌Pantoea agglomerans。致病性测定结果表明：该菌致病时间短，危害较大。主要通过伤口侵入植株叶片组织使得寄主发病，而植株茎干的损伤对植株发病短期内无明显影响，通过根际土壤接种发现，该细菌并不能直接由根部进入植株体内。%A pathogen,HT-1 ,was isolated from the walnut trees that exhibited the typical symptoms of the blight disease.Tests were performed to confirm the pathogenicity and taxonomy of the isolated bacteria.The bacterium was also morphologically identified along with confirmation by a 16S rDNA sequencing analysis to be Pantoea agglomerans.It was found that the open wounds on the tree leaves was the major gateway for the infection. However,in a short term,wounds on the stems did not seem to affect the occurrence of the disease,nor did the roots appear to be an entry for the pathogenic invasion to the plants.