野生大豆抗感大豆孢囊线虫材料内生细菌多样性分析

Endophytic bacterial diversity of wild soybean (Glycine soja) varieties with different resistance to soybean cyst nematode (Heterodera glycines)

摘要:

摘要:【目的】对抗感野生大豆材料根内生细菌的多样性进行比较分析，为研究野生大豆内生细菌与大豆孢囊线虫之间的相互关系奠定基础。【方法】在野生大豆抗大豆孢囊线虫3 号生理小种筛选基础上，利用扩增核糖体DNA 限制性分析(Amplified ribosomal DNA restriction analysis，AＲDＲA)和16S rDNA克隆文库测序相结合的方法，对抗感野生大豆根系内生细菌多样性及群落结构进行分析。【结果】野生大豆根内生细菌分属于6大类群，其中变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)为优势类群，相对丰度分别为46.8%和13.6%，另外有少量的放线菌门(Actinobacteria)、拟杆菌门(Bacteroidetes)、酸杆菌门(Acidobacteria)、异常球菌-栖热菌门(Deincoccus-Thermus)和古细菌(Archaea)，18.8% 克隆序列与环境中未培养细菌的16S rDNA序列有较高的相似性。野生大豆高抗材料内生细菌的多样性比高感材料更为丰富，且抗感材料内生细菌优势菌群存在明显差异，中慢生根瘤菌(Mesorhizobium tamadayense)、肠杆菌(Enterobacter ludwigii)和巨大芽孢杆菌(Bacillus megaterium)为野生大豆高抗材料特有的可操作分类单元(Operational Taxonomic Units，OTUs)中的优势种群。【结论】研究结果表明抗感野生大豆根内生细菌的优势种群存在明显差异，而内生细菌的优势种群与大豆孢囊线虫的相互关系正在深入分析研究。

Abstract:

Abstract: ［Objective］The aim of this study was to investigate endophytic bacterial diversity of wild soybean varieties with different resistance to soybean cyst nematode(Heterodera glycines)，for deciphering the interactions of soybean cyst nematode with endophytic bacteria． ［Methods］After screening wild soybean varieties against race 3 of H．glycines，we investigated endophytic bacterial diversity in root tissues of wild soybean varieties with different resistance to H．glycines using 16S rDNA cloning library and amplified ribosomal DNA restriction analysis.［Results］Endophytic bacteria of wild soybean root belonged to 6 bacterial groups，the clones belonging to group Proteobacteria and Firmicutes were the endophyte dominants in wild soybean with 46.8% and 13.6% of total clones， respectively．Actinobacteria，Bacteroidetes，Acidobacteria，Deincoccus-Thermus and Archaea were less represented． 18.8% of clone sequences were similar to those of uncultured bacteria in the environment．The bacterial diversity was higher in H． glycines-Ｒesistant than-Susceptible wild soybean varieties，and the dominant group was different between H．glycines-Ｒesistant and -Susceptible wild soybean varieties．Mesorhizobium tamadayense，Enterobacter ludwigii and Bacillus megaterium were the main bacterial groups in special operational taxonomic units (OTUs) of H．glycines-Ｒesistant wild soybean variety．［Conclusions］By 16S rDNA cloning library and amplified ribosomal DNA restriction analysis，the diversity of dominant group of endophytic bacteria in root tissues has difference among H．glycines-Ｒesistant and -Susceptible wild soybean varieties.