College of Plant Protection, Henan Agricultural University, Zhengzhou, 450002, China.
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Beijing, 100193, China.
Phytopathology. 2023 Jul;113(7):1210-1221. doi: 10.1094/PHYTO-06-22-0231-R. Epub 2023 Sep 1.
Canker and dieback are serious fungal diseases of woody plants that can cause huge economic losses to orchards. The purpose of this study was to classify and assess the pathogenicity of fungal species associated with canker and dieback on fruit trees growing in Henan Province, China. In total, 150 isolates of were obtained from six different fruit trees exhibiting typical symptoms of stem canker, branch dieback, and gummosis. Morphological examinations and phylogenetic analysis of ITS, , , and revealed two species, which are and a novel species, , respectively. Using Koch's postulates, we confirmed that the different isolates of can cause disease in their original hosts. The pathogenicity tests showed that can cause canker, dieback, and gummosis symptoms in four different hosts, indicating a relatively wider host range. Moreover, 10 isolates exhibited similar symptoms but different levels of virulence on shoots of peach trees under field conditions. This study demonstrated that was a new causal agent of canker and dieback of six fruit tree species, which could be a serious risk to the orchard industry in China. Furthermore, the findings provide a foundation for further epidemiological studies and the development of management strategies.
溃疡和枝枯是危害木本植物的两种严重真菌病害，可给果园带来巨大的经济损失。本研究旨在对中国河南省生长的果树溃疡和枝枯病相关真菌物种进行分类和致病性评估。从 6 种表现出典型茎溃疡、枝枯和流胶症状的不同果树中，共获得了 150 个 菌株。通过 ITS、、、和 的形态学观察和系统发育分析，鉴定出两种 物种，分别为 和一种新种 。通过柯赫氏假设，我们证实了不同的 分离株可以在其原始宿主中引起疾病。致病性测试表明，在四个不同的宿主中， 可引起溃疡、枝枯和流胶症状，表明其宿主范围较广。此外，在田间条件下，10 个分离株在桃树嫩枝上表现出相似的症状，但毒性水平不同。本研究表明， 是六种果树溃疡和枝枯病的一种新病原菌，可能对中国的果园产业构成严重威胁。此外，这些发现为进一步的流行病学研究和管理策略的制定提供了基础。
