Identification of walnut twig blight in Liaoning province.

Abstract

Objective: The walnut twig blight is a new disease in Liaoning province. The objective of the study was to identify the pathogen. Method: The walnut twig blight standard samples were collected from Jianchang County, Huludao City, Liaoning Province. The pathogen was identified by morphology, pathogenicity and ribosomal DNA-ITS. Results: The isolated fungus was used for department's law of disease and syndrome. Disease symptoms after inoculation were the same as that on the collected samples, which showed the fungus was the pathogen. The pycnidia and conidia' morphology of the pathogen were similar to that of Phomopsis juglandina. Comparing the measured sequence with the related sequence in GenBank, the homology was 99%. Conclusion: The studies suggested that the pathogen causing the walnut twig blight in Liaoning Province was Phomopsis juglandina.