大蒜根腐病根际土壤真菌群落结构及多样性分析

研究旨在解析根腐病发生时大蒜根际土壤真菌群落结构,明确大蒜根腐病与根际土壤真菌群落多样性变化的关系,探明根腐病发生的微生态机制,为病害的防控提供理论基础。以新疆连续3年的大蒜根腐病发病田的根际土壤为研究对象,采用高通量测序方法对大蒜根际土壤总DNA的真菌ITS区序列进行大规模测序分析。结果表明,与健康对照相比,在门的水平上,子囊菌门和接合菌门真菌是大蒜根腐病根际土壤的优势真菌类群,其中高水平的子囊菌门菌群与病害发生有着密切的关系。在属的水平上,注释获得137个属,其中19个属与大蒜根腐病有较大的相关性。镰刀菌属真菌数量在病土中高于健康对照。随着连作年限的延续,根腐病的发生愈发严重,土壤中真菌群落的Shannon指数、Simpson指数、真菌属的数量逐年降低,大蒜根腐病的发生与植株根际真菌群落组成及多样性密切相关,土壤真菌类群的平衡和多样性改变是根腐病发生的一大诱因。

Structures and Biodiversity of Fungal Communities in Rhizosphere Soil of Root Rot Diseased Garlic

The aim is to investigate the difference in structure and biodiversity of rhizosphere fungi communities when root rot occurs, clarify the relationship between garlic root rot and the diversity change of rhizosphere soil fungus community, explore the microecological mechanism of root rot occurrence, and provide a theoretical basis for the prevention and control of the disease. High-throughput sequencing method was used to analyze the fungal ITS region sequences of the total DNA of garlic rhizosphere soil in the fields affected by garlic root rot for 3 consecutive years in Xinjiang. The results showed that Ascomycota and Zygomycota were the main phyla in rhizosphere soil of diseased garlic, and the high levels of Ascomycota were closely related to the occurrence of garlic root rot disease. Totally 137 genera were found by annotation, of which 19 genera had great correlation with garlic root rot. The abundance of Fusarium spp. in rhizosphere soil of diseased plants was significantly higher than that of healthy plants. With the increase of the onset time, the number and biodiversity of fungi decreased year by year. Garlic root rot disease is closely related to the structure and diversity of rhizosphere fungi community, and the change of the balance and diversity of soil fungi is a major cause of root rot.