Xiao Xiao, Chen Weimin, Zong Le, Yang Jun, Jiao Shuo, Lin Yanbing, Wang Entao, Wei Gehong
State Key Laboratory of Crop Stress Biology in Arid Areas, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 11340, México, D.F., Mexico.
Mol Ecol. 2017 Mar;26(6):1641-1651. doi: 10.1111/mec.14027. Epub 2017 Feb 23.
The microbiomes of rhizocompartments (nodule endophytes, root endophytes, rhizosphere and root zone) in soya bean and alfalfa were analysed using high-throughput sequencing to investigate the interactions among legume species, microorganisms and soil types. A clear hierarchical filtration of microbiota by plants was observed in the four rhizocompartments - the nodule endosphere, root endosphere, rhizosphere and root zone - as demonstrated by significant variations in the composition of the microbial community in the different compartments. The rhizosphere and root zone microbial communities were largely influenced by soil type, and the nodule and root endophytes were primarily determined by plant species. Diverse microbes inhabited the root nodule endosphere, and the corresponding dominant symbiotic rhizobia belonged to Ensifer for alfalfa and Ensifer-Bradyrhizobium for soya bean. The nonsymbiotic nodule endophytes were mainly Proteobacteria, Actinobacteria, Firmicutes and Bacteroidetes. The variation in root microbial communities was also affected by the plant growth stage. In summary, this study demonstrated that the enrichment process of nodule endophytes follows a hierarchical filtration and that the bacterial communities in nodule endophytes vary according to the plant species.
利用高通量测序技术分析了大豆和苜蓿根际微生境（根瘤内生菌、根内生菌、根际和根区）的微生物群落，以研究豆科植物物种、微生物和土壤类型之间的相互作用。在四个根际微生境——根瘤内圈、根内圈、根际和根区中，观察到植物对微生物群有明显的分层筛选作用，不同微生境中微生物群落组成的显著差异证明了这一点。根际和根区的微生物群落很大程度上受土壤类型的影响，而根瘤和根内生菌主要由植物物种决定。多种微生物栖息在根瘤内圈，苜蓿根瘤内相应的优势共生根瘤菌属于中华根瘤菌属，大豆根瘤内相应的优势共生根瘤菌属于中华根瘤菌属-慢生根瘤菌属。非共生根瘤内生菌主要是变形菌门、放线菌门、厚壁菌门和拟杆菌门。根际微生物群落的变化也受植物生长阶段的影响。总之，本研究表明根瘤内生菌的富集过程遵循分层筛选，且根瘤内生菌中的细菌群落因植物物种而异。
