• Alternaria malorum as the causal agent of bark canker on walnut trees
  • Alternaria malorum is a new fungal pathogen of walnut trees in the world
  • Identification the pathogenic fungus caused bark canker disease on walnut trees on the basis of morphological characteristics and molecular assay for the first time in the world
  • The present study was focused on identification of causal agent, which involve in pathogenicity. It comprises systematics, taxonomy and pathogenicity
During 2016–2020, a longitudinal bark canker was observed on walnut branches in some of the provinces of Iran. The symptoms appeared on one side of the branches. No visible symptoms were observed on the sapwood after removal of the bark using a blade. In order to detect a potential agent of these symptoms on walnut trees, collected samples were transferred to the laboratory for further investigation. After isolation and purification based on standard methods, a fungus was frequently isolated from symptomatic tissues. Morphological and molecular assays indicated that the responsible agent of this disease was Alternaria malorum, moreover, a pathogenicity test confirmed that A. malorum was pathogenic on walnut trees. To the best of our knowledge, this study represents the first attempt to identify A. malorum as a new causative agent of bark canker on walnut trees in the world.
The authors would like to thank the Research Deputy of the University of Bu-Ali sina, Hamedan, Iran for their financial support of this project.
Lidia Irzykowska
The authors have declared that no conflict of interests exist.
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