健康与根结线虫病烟田根际土壤微生物群落对比分析

为了研究烟草根结线虫病与根际土壤微生物群落的关系,通过高通量测序研究了健康烟田和根结线虫病发病烟田根际土壤的微生物多样性、组成结构和功能变化。结果表明：健康烟田根际土壤微生物群落的Alpha多样性与发病烟田差异不显著,Beta多样性分析表明健康烟田样本与发病烟田样本分布基本一致。健康烟田与根结线虫发病烟田根际土壤细菌与真菌微生物群落在门水平上组成相似,但物种丰度存在差异,酸杆菌门(Acidobacteria)、放线菌门(Actinobacteria)、担子菌门(Basidiomycota)和壶菌门(Chytridiomycota)在健康烟田中占优势,而变形菌门(Proteobacteria)、芽单胞菌门(Gemmatimonadetes)、子囊菌门(Ascomycoda)、球囊菌门(Mortierellomycota)在发病烟田中占优势。在属水平上,根际土壤细菌与真菌微生物群落组成也基本一致,但健康烟田与根结线虫发病烟田微生物物种丰度存在显著差异,Cylidrocapon、镰刀菌属(Fusarium)等致病菌在发病烟田中占显著优势。种水平上,健康烟田中的Actinoallomurus spadix和分枝节杆菌(Arhrobacter ramosus)与发病烟田组存在显著差异。通过根际土壤微生物功能预测分析发现,发病和健康烟田土壤真菌、细菌功能组成相似,但发病烟田样本功能丰度大于健康烟田。因此,烟草根结线虫病的发生与根际土壤微生物群落的组成和多样性无直接关系,而是可能与物种丰度及样本功能丰度密切相关。研究结果可为通过调控根际微生物群落结构来防治烟草根结线虫病提供理论依据。

Comparative Analysis of Microbial Communities in Rhizosphere Soil of Healthy and Root-knot Nematodes-infected Tobacco Fields

To study the relationship between tobacco root-knot nematode disease and rhizosphere soil microbial communities, high-throughput sequencing was used to study the microbial diversity, composition structure and function of rhizosphere soil in healthy and diseased tobacco fields. The results show that there is no significant difference in the Alpha diversity of the rhizosphere soil microbial communities between healthy and diseased tobacco fields. Beta diversity analysis shows that the distribution of samples from healthy and diseased tobacco fields is basically the same. The bacterial and fungal microbial communities in the rhizosphere soil of healthy and infected tobacco fields are similar in composition at the phylum level, but there are differences in species abundance. Acidobacteria, Actinobacteria, Basidiomycota and Chytridiomycota are dominant in healthy tobacco fields, while Proteobacteria and Gemmatimonadetes, Ascomycoda and Mortierellomycota are dominant in diseased tobacco fields. At the genus level, the microbial community composition of rhizosphere soil bacteria and fungi are basically the same, but there is significant difference in the microbial species abundance between healthy and root-knot nematode-infected tobacco fields, and the pathogenic bacteria such as Cylidrocapon, Fusarium are dominant in the diseased tobacco field. At the species level, Actinoallomurus spadix and Arhrobacter ramosus in healthy tobacco fields are significantly different from those in diseased tobacco fields. Through the prediction analysis of rhizosphere soil microbial function, it is found that the functional composition of fungi and bacteria in diseased and healthy tobacco fields are similar, but the functional abundance of diseased tobacco fields is higher than that of healthy tobacco fields. Therefore, infection of nematodes is not directly related to the composition and diversity of the rhizosphere soil microbial community, but might be closely related to the abundance of certain species and sample functional abundance. The study could provide a theoretical basis for controlling tobacco root knot nematode disease by regulating rhizosphere microbial community structure.