Abstract: High-performance 16S rRNA analysis was performed on rhizosphere bacteria from Cardamine hupingshanesis to demonstrate their roles on selenium(Se)-hyperaccumulation by C. hupingshanesis. Compared with the normal soils in study site, there have much higher contents of microorganisms but less microbial diversity in the rhizosphere of C. hupingshanesis, and it was predominant by α-proteobacteria class (15%~22%), β-proteobacteria class (10%~16%), Actinobacteria class (10%~18%), Acidobacteria class (8%~15%), γ-proteobacteria class (5%~16%). Moreover, some special microorganism were characterized with Nitrospira class (2%~5%), Gemmatimonadetes class (2%~5%), Verrucomicrobiae class (2%~4%), Planctomycetacia class (1%~2%) and others (Opitutae class, Sphingobacteria class, Bacilli class, Clostridia class) (3%~4%). Especially, the typical bacteria, such as α-proteobacteria class and Nitrospira class could play important roles during Se-hyperaccumulation for C. hupingshanesis.

Key words: Cardamine hupingshanesis, rhyzosphere bacteria, selenium hyperaccumulation, α-proteobacteria class, Nitrospira class

摘要： 对湖北恩施的硒超积累植物——壶瓶碎米荠的根际微生物特征进行16S rRNA基因文库分析，结果显示其根际微生物相较于非根际土壤微生物具有更高的丰度和更低的复杂度，而且主要由α-变形菌纲（15%~22%）、β-变形菌纲（10%~16%）、放线菌纲（10%~18%）、酸杆菌纲（8%~15%）、γ-变形菌纲（5%~16%）等组成；此外，根际微生物还存在很多特异性微生物，如：硝化螺旋菌纲（2%~5%）、芽单孢菌纲（2%~5%）、疣微菌纲（2%~4%）、浮霉菌纲（1%~2%）、其他（丰佑菌纲、鞘脂杆菌纲、芽孢杆菌纲、梭菌纲）（3%~4%）。代表性的根际微生物α-变形菌纲和硝化螺旋菌纲可能在壶瓶碎米荠对硒的吸收、积累过程中扮演了重要的作用。

关键词: 壶瓶碎米荠, 根际微生物, 硒超积累, α-变形菌纲, 硝化螺旋菌纲