黄河三角洲不同类型盐生植物土壤真菌群落结构特征

Structural Characteristics of Fungi Communities in Soil of Different Halophytes in the Yellow River Delta

盐生植物种类及其所具有的不同耐盐调节方式影响着根际微生物群落的结构与组成。为明确不同类型盐生植物根际与非根际土壤中真菌群落结构与组成的差异及其与土壤环境间的相互关系,该研究采集了黄河三角洲地区芦苇、盐地碱蓬、獐毛3种不同类型盐生植物0~20 cm土层的根际和非根际土壤,通过高通量测序对其真菌群落多样性和结构进行了分析,以探究真菌群落特征与土壤理化因子间的关系。结果表明:(1)3种不同类型盐生植物根际土壤真菌群落丰富度显著大于各自非根际土,且獐毛根际土壤真菌群落丰富度显著大于芦苇和盐地碱蓬的根际土。(2)距离热图分析表明,芦苇和盐地碱蓬非根际土壤真菌群落间的相似性最大。(3)土壤真菌多样性和丰富度与土壤总碳、总氮、有效磷、pH呈正相关关系,与土壤盐分含量呈负相关关系。(4)3种不同类型盐生植物的根际与非根际土壤中,球囊菌门(Glomeromycota)均为绝对优势门,盾巨孢囊霉属(Scutellospora)为优势属。(5)RDA分析表明,土壤盐分含量是影响土壤真菌群落结构的重要因子,球囊菌门丰度与土壤总氮、总碳、有效磷、有机碳、pH呈正相关关系,与盐分呈负相关关系。(6)植物土壤真菌群落特征随盐生植物类型的变化以及样本土壤距宿主植物根系远近存在差异。

The structure and composition of rhizosphere microbial communities are affected by halophyte species and their different salt tolerance regulation modes.In order to clarify the difference of fungal community structure and composition between rhizosphere and bulk soils of different halophytes and their relationship with soil environment,we collected rhizosphere and bulk soil of Phragmites communis,Suaeda salsa,and Aeluropus sinensis from the 0-20 cm soil layer of three halophytes in the Yellow River Delta.The diversity and structure of the fungal community were analyzed by high-throughput sequencing,and the relationship between the fungal community characteristics and soil physical and chemical factors was explored.The results showed that:(1)the fungal richness is higher in rhizosphere than in bulk soil for all three halophyte species and the highest fungal richness was found in rhizosphere soil of Aeluropus sinensis.(2)The distance heat map showed that the similarity between P.communis and S.salsa bulk soil fungal communities was the greatest.(3)Soil fungal diversity and richness were positively correlated with soil total carbon,total nitrogen,available phosphorus and pH,but negatively correlated with soil salt content.(4)In rhizosphere and bulk soils of three halophytes,Glomeromycota was the absolute dominant phylum,while Scutellospora was the dominant genus.(5)RDA analysis showed that soil salt content was an important factor affecting soil fungal community structure,and the abundance of Glomeromycota was positively correlated with soil total nitrogen,total carbon,available phosphorus,organic carbon and pH,while negatively correlated with soil salt.(6)The characteristics of plant soil fungal community varied with the type of halophytes and the distance from the soil samples to the roots of host plants.