State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, PR China.
Sci Total Environ. 2018 Dec 10;644:791-800. doi: 10.1016/j.scitotenv.2018.07.016. Epub 2018 Jul 11.
Fungi play a crucial role in the agroecological system; however, little is known about their large-scale biogeographical patterns and how various ecological processes contribute to community assembly, especially in the crop rhizosphere. In this study, we investigated the spatial distribution and community assembly of fungi in the bulk soil and rhizosphere of soybean collected from 43 sites across China using high-throughput sequencing. The alpha diversity of the rhizosphere was lower than that of bulk soil. The fungal community structures of the two soil compartments were distinct. Fungal communities in the rhizosphere had a steeper distance-decay relationship slope between sampled sites than those in bulk soil, suggesting a greater influence of historical processes (geographical separation) in the rhizosphere. The relative importance of dispersal limitation and environmental filtering for the fungal community composition differed between bulk soil and rhizosphere. Sloan neutral model analysis suggested that niche-based processes dominated the assemblage of fungal communities in the two soil compartments, while neutral processes had a weaker influence in the rhizosphere than in bulk soil. Additionally, we analyzed the structures of abundant and rare fungal sub-communities in each soil compartment. Rare sub-communities were more strongly influenced by dispersal limitation than abundant sub-communities. These results expand the current understanding of root-associated fungal community biogeography in agricultural soils on a large scale.
真菌在农业生态系统中起着至关重要的作用；然而，人们对它们的大规模生物地理格局以及各种生态过程如何促成群落组装知之甚少，特别是在作物根际。在这项研究中，我们使用高通量测序技术，调查了来自中国 43 个地点的大豆根际和非根际土壤中真菌的空间分布和群落组装。根际的 alpha 多样性低于非根际土壤。两个土壤区室的真菌群落结构明显不同。根际真菌群落的采样点之间的距离衰减关系斜率比非根际土壤陡峭，表明历史过程（地理隔离）在根际中具有更大的影响。扩散限制和环境过滤对真菌群落组成的相对重要性在非根际和根际土壤之间存在差异。Sloan 中性模型分析表明，基于生态位的过程主导了两个土壤区室中真菌群落的组装，而中性过程对根际的影响比非根际土壤弱。此外，我们分析了每个土壤区室中丰富和稀有真菌亚群落的结构。稀有亚群落比丰富亚群落受扩散限制的影响更大。这些结果扩展了我们对农业土壤中根相关真菌群落生物地理学的现有认识。
