Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland.
Department of Microbiology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa.
Environ Microbiol. 2023 Nov;25(11):2250-2265. doi: 10.1111/1462-2920.16455. Epub 2023 Jun 25.
Emerging diseases caused by both native and exotic pathogens represent a main threat to forest ecosystems worldwide. The two invasive soilborne pathogens Phytophthora cinnamomi and Phytophthora × cambivora are the causal agents of ink disease, which has been threatening Castanea sativa in Europe for several centuries and seems to be re-emerging in recent years. Here, we investigated the distribution, causal agents, and infection dynamics of ink disease in southern Switzerland. A total of 25 outbreaks were identified, 19 with only P. cinnamomi, 5 with only P. × cambivora, and 1 with both species. Dendrochronological analyses showed that the disease emerged in the last 20-30 years. Infected trees either died rapidly within 5-15 years post-infection or showed a prolonged state of general decline until death. Based on a generalized linear model, the local risk of occurrence of ink disease was increased by an S-SE aspect of the chestnut stand, the presence of a pure chestnut stand, management activities, the proximity of roads and buildings, and increasing annual mean temperature and precipitation. The genetic structure of the local P. cinnamomi population suggests independent introductions and local spread of the pathogen.
由本地和外来病原体引起的新发传染病是对全球森林生态系统的主要威胁。两种入侵性土壤病原体樟疫霉和樟疫霉杂种是墨水病的致病因子，这种病已经在欧洲威胁山核桃几个世纪了，近年来似乎又重新出现。在这里，我们调查了瑞士南部墨水病的分布、病原体和感染动态。共确定了 25 个暴发点，其中 19 个只有樟疫霉，5 个只有樟疫霉杂种，1 个同时有两种病原体。树木年代学分析表明，这种疾病是在过去 20-30 年内出现的。感染的树木要么在感染后 5-15 年内迅速死亡，要么在死亡前表现出长时间的普遍衰退状态。基于广义线性模型，墨水病发生的局部风险受栗树林的南-东南朝向、纯栗树林的存在、管理活动、道路和建筑物的接近程度以及年平均温度和降水的增加而增加。当地樟疫霉种群的遗传结构表明，病原体是独立传入和本地传播的。
