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Issue: Vol. 728 No. 2: 12 Nov. 2025
Type: Article
Published: 2025-11-12
DOI: 10.11646/phytotaxa.728.2.4
Page range: 141-152
Abstract views: 116
PDF downloaded: 1

Cytospora juglandigena sp. nov. causing walnut branch dieback in Xinjiang, China

School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
Xinjiang Uygur Autonomous Region Academey of Forestry Sciences
Xinjiang Uygur Autonomous Region Academey of Forestry Sciences
School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China
Cytospora morphology multi-gene phylogeny pathogenicity Fungi

Abstract

Cytospora species are common pathogens associated with stem canker diseases of woody plants, with a wide range of hosts, and have a global distribution. Cytospora species have also caused serious stem disease in walnut. In this study, 67 isolates of Cytospora were collected from Juglans regia associated with symptomatic dieback and blight disease in Xinjiang, China. Morphological characterization and multi-locus phylogenetic analyses of concatenated ITS, RPB2, and tef1-α sequences demonstrated that these isolates represent a novel species. Pathogenicity tests confirmed, through Koch’s postulates, that Cytospora juglandigena is the causal agent of branch dieback in walnut.

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How to Cite

Zhao, L.-L., Wang, J.-W., Kong, T.-T., Liu, A.-H. & Zhang, Y. (2025) Cytospora juglandigena sp. nov. causing walnut branch dieback in Xinjiang, China. Phytotaxa 728 (2): 141–152. https://doi.org/10.11646/phytotaxa.728.2.4