Key Laboratory of Mollisols Agroecology, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun, 130102, Jilin, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Arch Microbiol. 2021 Jul;203(5):2157-2170. doi: 10.1007/s00203-021-02196-8. Epub 2021 Feb 22.
Soil physicochemical properties and fungal communities are pivotal factors for continuous cropping of American ginseng (Panax quinquefolium L.). However, the response of soil physicochemical properties and fungal communities to replant disease of American ginseng has not yet been studied. High-throughput sequencing and soil physicochemical analyses were undertaken to investigate the difference of soil fungal communities and environmental driver factors in new and old ginseng fields; the extent of replant disease in old ginseng fields closely related to changes in soil properties and fungal communities was also determined. Results indicated that fungal communities in an old ginseng field were more sensitive to the soil environment than those in a new ginseng field, and fungal communities were mainly driven by soil organic matter (SOM), soil available phosphorus (AP), and available potassium (AK). Notably, healthy ginseng plants in new and old ginseng fields may influence fungal communities by actively recruiting potential disease suppressive fungal agents such as Amphinema, Cladophialophora, Cadophora, Mortierella, and Wilcoxina. When these key groups and members were depleted, suppressive agents in the soil possibly declined, increasing the abundance of pathogens. Soil used to grow American ginseng in the old ginseng field contained a variety of fungal pathogens, including Alternaria, Armillaria, Aphanoascus, Aspergillus, Setophoma, and Rhexocercosporidium. Additionally, micro-ecological factors affecting disease outbreaks in the old ginseng field included a strengthening in competition relationships, a weakening in cooperation relationships, and a change of trophic strategies among fungal communities.
土壤理化性质和真菌群落是西洋参（Panax quinquefolium L.）连作的关键因素。然而，土壤理化性质和真菌群落对西洋参连作障碍的响应尚未得到研究。本研究采用高通量测序和土壤理化分析的方法，研究了新、老参地土壤真菌群落的差异及环境驱动因子；同时还确定了老参地西洋参连作障碍的严重程度与土壤性质和真菌群落的变化密切相关。结果表明，老参地土壤真菌群落对土壤环境的变化比新参地更为敏感，真菌群落主要受土壤有机质（SOM）、土壤有效磷（AP）和有效钾（AK）的驱动。值得注意的是，新、老参地健康西洋参植株可能通过积极招募潜在的病害抑制真菌剂（如 Amphinem a、Cladophialophora、Cadophora、Mortierella 和 Wilcoxina）来影响真菌群落。当这些关键类群和成员减少时，土壤中的抑制性物质可能会减少，导致病原菌丰度增加。老参地用于种植西洋参的土壤中含有多种真菌病原体，包括链格孢属（Alternaria）、蜜环菌属（Armillaria）、无梗囊霉属（Aphanocascus）、曲霉属（Aspergillus）、叶点霉属（Setophoma）和壳二孢属（Rhexocercosporidium）。此外，影响老参地病害爆发的微生态因素包括竞争关系的加强、合作关系的减弱以及真菌群落营养策略的改变。
