【摘要】 【目的】探究不同区域栽培太子参产生连作效应的潜在原因。【方法】采用高通量测序对柘荣县5个样地的太子参根际土壤进行微生物群落结构及多样性分析。【结果】土壤真菌的有效序列共744 331条,聚类后获得1 314个真菌分类单元;获得细菌1 032 029条有效序列,聚类后获得10 310个细菌分类单元。5个样地的共有OTU数明显多于每个样地特有的OTU数,表明不同样地的太子参根际土壤微生物群落趋势大致相同。α多样性分析表明,不同样地根际土壤微生物群落组成及丰度之间有明显差异,Ⅳ、Ⅱ、Ⅰ样地的物种丰度较高,而Ⅴ、Ⅲ样地的物种丰度较低。典范对应分析表明土壤化学性质和根系分泌物酚酸类物质影响太子参根际土壤微生物的群落分布。5个样地中都鉴定到镰刀菌属等致病真菌,且致病菌的含量与根际土壤其他微生物物种数呈反比,暗示镰刀菌影响太子参根际土壤其他微生物物种数。【结论】太子参连作效应及其病害的成因很大程度上归因于其根系分泌物参与调控的根际微生物菌群结构和多样性演变,导致病原菌增多。更多还原

【Abstract】 【Objective】 Chemical and microbial factors in field soils related to disease occurrence of continuously cropped Pesudostellaria heterophylla were investigated. 【Method】 Microbial community structure and diversity of rhizosphere soil from 5 continuous cropping P. heterophylla fields in Zherong County, Fujian were analyzed on data obtained by highthroughput sequencing technology. Correlation analysis of the microbial distribution was conducted based on the chemical properties of rhizosphere soil and phenolic acids. 【Result】 A clustering analysis on 744,331 fungal and 1,032,029 bacterial effective sequences resulted in 1,314 operational taxonomic units for the fungi and 10,310 for the bacteria. At each of the 5 locations, the number of common OTUs was significantly greater than that of unique ones. On the other hand, the alpha diversity analysis showed significant differences in microbial composition and abundance among the habitats as the species richness at Habitat Ⅳ, Ⅱ, and Ⅰ were higher than those at Habitat Ⅴ and Ⅲ. The canonical correspondence analysis indicated the soil chemical properties and phenolic acids in the root exudates significantly affected the microbial distribution. Fusarium and other pathogenic fungi were found at all 5 sites with the count of the pathogenic fungi inversely proportional to that of other microbial species, i.e., a possible correlation between Fusarium and the rhizosphere community. 【 Conclusion】 It appeared that the continuous cropping that frequent fungal diseases on the plants might be significantly associated with the evolution of rhizosphere microbial structure and diversity mediated by the root exudate from P. heterophylla itself.更多还原