茎瘤芥(榨菜)根肿病不同发病时期根际土壤真菌群落变化特征的高通量分析

茎瘤芥(榨菜)根肿病是一种土传病害,与根际土壤真菌群落存在密切关系。本试验采用454高通量测序方法,以土壤真菌的18Sr DNA序列为靶标,研究茎瘤芥根肿病不同发病时期(移栽前、移栽后发病前、发病初期、发病中期、采收后)土壤真菌群落的变化规律。结果表明:经454高通量测序,茎瘤芥根肿病各发病时期的OUT平均数量为1056个。依据OUT所属真菌物种信息对土壤真菌群落结构进行分析,子囊菌亚门真菌在各个时期土壤中均为优势真菌类群,其次为担子菌亚门真菌。移栽后发病前、发病初期和发病中期土壤真菌群落的Shannon和Simpson多样性指数、OTU数量和属的数量均高于移栽前和采收后,表明茎瘤芥根肿病发生发展时期土壤真菌群落多样性较高,这可能与茎瘤芥生长季节根系分泌物旺盛有关。

High Throughput Analysis on Change Characteristics of Rhizosphere Soil Fungal Community during Different Occurance Times of Tuber Mustard Clubroot#br# Disease

Tuber mustard clubroot is a soil-borne disease and closely related with soil fungal community．In this study，the change regulation of soil fungal community during different occurance times of tuber mustard clubroot（pre-transplanting，premorbid after transplant，early and middle stages of disease occurance，after harvest）was sequenced by 454 high-throughout method using 18S rDNA sequence of soil fungi as target．The results showed that average of 1 056 OTUs（Operational Taxonomic Units）were obtained from one soil sample．According to taxonomy of each OTU，the dominant group was Ascomycetes，followed by Basidiomycota．The diversity indexes of Shannon and Simpson，numbers of OTU and genera in premorbid after transplanting，early and middle stages were all higher than that in pre-transplanting stage and after harvesting stage．The results indicated that the diversity of soil fungal community is higher in the period of tuber mustard clubroot development．It might be related to the vigorous production of root exudate of tuber mustard．