土壤真菌在土壤生态环境中起着至关重要的作用,长期单作或连作会导致土壤真菌群落结构发生变化.为研究长期连作对草莓植株健康和根际真菌群落组成的影响,采用Illumina MiSeq测序技术,比较分析未连作(CK)和不同连作年限(1、2、4、7、9、11 年)温室草莓根际土壤性质及真菌群落的结构特征.结果表明,草莓连作后土壤理化性质发生显著变化,连作 4 年后养分含量开始明显下降.高通量测序表明,土壤真菌群落丰富度和多样性随连作年限增加而增加,土传病害菌镰刀菌属(Fusarium)、腐质霉属(Humicola)、久浩酵母属(Guehomyces)丰度显著增加,斗管囊霉属(Funneliformis)、节丛孢属(Arthrobotrys)丰度从连作第 4 年开始下降.Spearman相关性分析表明,土壤pH值、速效钾和速效氮是判定草莓连作系统中有益菌群与致病菌群结构的主要因素.RDA分析表明,pH值、速效氮是决定连作系统中Funneliformis、Arthrobotrys丰度的主要土壤因子;速效钾是影响Guehomyces、Humicola、Fusarium丰度的主要土壤因子.本研究结果可为草莓种植的可持续发展及连作土壤治理提供理论依据.
Soil fungi play important roles in soil ecological environment.In agricultural production,long-term monoculture and continuous cropping can lead to changes in fungal community structure.However,the effects of long-term continuous cropping on strawberry plant health and rhizosphere fungal community composi-tion are still unclear.In this study,the Illumina-MiSeq technique was used,and the rhizosphere soil properties and fungal community structure characteristics of greenhouse strawberry between non-continuous cropping(CK)and continuous cropping with different years(1,2,4,7,9,11 a)were analyzed.The results showed that the soil properties changed significantly after continuous cropping of strawberry,and the soil nutrient con-tent began to decrease significantly after 4-year continuous cropping.High-throughput sequencing results showed that the richness and diversity of soil fungal communities increased with the increase of continuous cropping years.Specifically,the abundance of Fusarium,Humicola and Guehomyces increased significantly af-ter strawberry continuous cropping,while that of Funneliformis and Arthrobotrys decreased from the 4th year of continuous cropping.Spearman correlation analysis showed that soil pH,available potassium and available ni-trogen were the main factors to determine the structure of beneficial bacteria and pathogenic bacteria in straw-berry continuous cropping system.Furthermore,the redundancy analysis(RDA)results showed that soil pH and available nitrogen were the main factors determining the abundance of Funneliformis and Arthrobotrys in continuous cropping system,and available potassium was the main soil factor affecting the abundance of Gue-homyces,Humicola and Fusarium.The results of this study could provide theoretical references for sustainable development of strawberry planting and continuous cropping soil management.