Ikeda Seishi, Rallos Lynn Esther E, Okubo Takashi, Eda Shima, Inaba Shoko, Mitsui Hisayuki, Minamisawa Kiwamu
Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
Appl Environ Microbiol. 2008 Sep;74(18):5704-9. doi: 10.1128/AEM.00833-08. Epub 2008 Jul 25.
Microorganisms associated with the stems and roots of nonnodulated (Nod(-)), wild-type nodulated (Nod(+)), and hypernodulated (Nod(++)) soybeans [Glycine max (L.) Merril] were analyzed by ribosomal intergenic transcribed spacer analysis (RISA) and automated RISA (ARISA). RISA of stem samples detected no bands specific to the nodulation phenotype, whereas RISA of root samples revealed differential bands for the nodulation phenotypes. Pseudomonas fluorescens was exclusively associated with Nod(+) soybean roots. Fusarium solani was stably associated with nodulated (Nod(+) and Nod(++)) roots and less abundant in Nod(-) soybeans, whereas the abundance of basidiomycetes was just the opposite. The phylogenetic analyses suggested that these basidiomycetous fungi might represent a root-associated group in the Auriculariales. Principal-component analysis of the ARISA results showed that there was no clear relationship between nodulation phenotype and bacterial community structure in the stem. In contrast, both the bacterial and fungal community structures in the roots were related to nodulation phenotype. The principal-component analysis further suggested that bacterial community structure in roots could be classified into three groups according to the nodulation phenotype (Nod(-), Nod(+), or Nod(++)). The analysis of root samples indicated that the microbial community in Nod(-) soybeans was more similar to that in Nod(++) soybeans than to that in Nod(+) soybeans.
通过核糖体基因间隔区分析（RISA）和自动RISA（ARISA）对与未结瘤（Nod(-)）、野生型结瘤（Nod(+)）和超结瘤（Nod(++)）大豆[大豆（Glycine max (L.) Merril）]的茎和根相关的微生物进行了分析。茎样本的RISA未检测到与结瘤表型特异的条带，而根样本的RISA显示了结瘤表型的差异条带。荧光假单胞菌仅与Nod(+)大豆根相关。茄腐镰刀菌稳定地与结瘤（Nod(+)和Nod(++)）根相关，在Nod(-)大豆中含量较少，而担子菌的丰度则相反。系统发育分析表明，这些担子菌可能代表木耳目中与根相关的类群。ARISA结果的主成分分析表明，茎中的结瘤表型与细菌群落结构之间没有明显关系。相比之下，根中的细菌和真菌群落结构均与结瘤表型有关。主成分分析进一步表明，根中的细菌群落结构可根据结瘤表型（Nod(-)、Nod(+)或Nod(++)）分为三组。根样本分析表明，Nod(-)大豆中的微生物群落与Nod(++)大豆中的微生物群落比与Nod(+)大豆中的微生物群落更相似。
