间作木薯对橡胶树根际土壤真菌群落结构的影响

研究间作木薯对橡胶树根际土壤真菌群落多样性变化规律,为判断胶园间作木薯的可行性提供理论支撑。以橡胶与木薯间作为处理,橡胶单作为对照,采用传统方法和高通量测序技术分析橡胶树根际土壤理化性状及真菌群落结构。结果表明：（1）间作模式下橡胶树根际土壤的碱解氮、速效磷、速效钾、有机质含量和真菌Shannon指数显著降低,真菌Simpson指数显著提高,pH和Chao1指数虽有降低,但差异未达到显著水平;（2）门分类水平上,2个处理的橡胶树根际土壤真菌群落结构组成相近,共有的3大优势菌门均为Ascomycota、Zygomycota和Basidiomycota。间作木薯降低了橡胶树根际土壤中Zygomycota和Basidiomycota的相对丰度,但提高了Ascomycota相对丰度,达到91.54%;（3）属分类水平上,2个处理中相对丰度比例前10的优势菌属占所有检测出菌属的61.30%~65.59%,间作木薯提高了橡胶根际土壤中Phyllosticta、Gibberella和Lecythophora的相对丰度;（4）土壤碱解N、速效P和速效K含量对橡胶树根际土壤中真菌群落α-多样性产生影响,土壤真菌多样性变化与土壤有机质含量有关。因此,间作木薯增加了植物对土壤矿质营养元素的吸收,导致橡胶树根际土壤肥力下降,进一步降低了橡胶树根际土壤真菌的群落多样性,同时增加了病原真菌的丰度。

Effects of Rubber-cassava Intercropping on Soil Fungal Community Structure in Rhizosphere of Rubber Trees

To explore the effect of rubber-cassava intercropping on the soil fungal community structure in the rhizosphere of rubber trees, the soil physiochemical properties, fungal community structure in the rhizosphere of rubber trees were analyzed by traditional and high-throughput sequencing techniques. Compared to rubber monoculture, the contents of soil alkalide N, available P, available K, organic matter and Shannon index of fungal diversity in the rhizosphere of rubber trees of rubber-cassava intercropping were significantly decreased, but the Simpson index was significantly increased. In addition, there were no significant differences for soil pH and chao1 index. Ascomycota, Zygomycota and Basidiomycota were the three dominant fungi at phylum level for both intercropping and monoculture treatments, but compared to monoculture, the relative abundance of Zygomycota and Basidiomycota were decreased, and Ascomycota was increased to 91.54% in intercropping treatment. At the genus level, the top 10 fungal genera accounted for 61.30%-65.59% of the total genera. The relative abundance of Phyllosticta, Gibberella and Lecythophora were higher in the intercropping treatment. The α-diversity of fungi was not only interfered by the content of soil alkalide nitrogen, available phosphorus and potassium, but was also affected by the content of soil organic matter. It indicated that rubber-cassava intercropping significantly decreased soil nutrients content and fungal diversity in the rhizosphere of rubber trees. Meanwhile, the relative abundance of soil pathogenic fungi in the rhizosphere was also enriched by intercropping treatment.