Identification and Pathogenicity Assay of Pathogen of Blight Disease on Walnut Trees in Longnan

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.