Bolaji Ayooluwa J, Wan Joey C, Manchur Christopher L, Lawley Yvonne, de Kievit Teresa R, Fernando W G Dilantha, Belmonte Mark F
Department of Biological Sciences, University of Manitoba, Winnipeg, MB, Canada.
Department of Plant Science, University of Manitoba, Winnipeg, MB, Canada.
Front Microbiol. 2021 Feb 11;12:632280. doi: 10.3389/fmicb.2021.632280. eCollection 2021.
The microbial composition of the rhizosphere soil could be an important determinant of crop yield, pathogen resistance, and other beneficial attributes in plants. However, little is known about the impact of cropping sequences on microbial community dynamics, especially in economically important species like soybean. Using 2-year crop sequences of corn-soybean, canola-soybean, and soybean-soybean, we investigated how crops from the previous growing season influenced the structure of the microbiome in both the bulk soil and soybean rhizosphere. A combination of marker-based Illumina sequencing and bioinformatics analyses was used to show that bacterial species richness and evenness in the soybean rhizosphere soil were similar following canola and soybean compared to a previous corn sequence. However, fungal species richness and evenness remained unaffected by crop sequence. In addition, bacterial and fungal species diversity in both the bulk and soybean rhizosphere soil were not influenced by crop sequence. Lastly, the corn-soybean sequence significantly differed in the relative abundance of certain bacterial and fungal classes in both the soybean rhizosphere and bulk soil. While canola-soybean and a continuous soybean sequence did not, suggesting that a preceding corn sequence may reduce the occurrence of overall bacterial and fungal community members. For the present study, crop sequence impacts bacterial diversity and richness in both the bulk soil and soybean rhizosphere soil whereas fungal diversity and richness are resilient to crop sequence practices. Together, these findings could help drive decision making for annual crop and soil management practices.
根际土壤的微生物组成可能是作物产量、病原体抗性及植物其他有益特性的重要决定因素。然而，对于种植顺序对微生物群落动态的影响，我们了解甚少，尤其是在大豆这类具有重要经济价值的作物中。我们利用玉米-大豆、油菜-大豆和大豆-大豆的两年作物种植顺序，研究了前一生长季的作物如何影响大田土壤和大豆根际微生物组的结构。通过基于标记的Illumina测序和生物信息学分析相结合的方法，结果表明，与之前的玉米种植顺序相比，油菜和大豆种植后，大豆根际土壤中的细菌物种丰富度和均匀度相似。然而，真菌物种丰富度和均匀度不受作物种植顺序的影响。此外，大田土壤和大豆根际土壤中的细菌和真菌物种多样性也不受作物种植顺序的影响。最后，玉米-大豆种植顺序在大豆根际和大田土壤中某些细菌和真菌类群的相对丰度上存在显著差异。而油菜-大豆和连续大豆种植顺序则没有，这表明前茬玉米种植顺序可能会减少整体细菌和真菌群落成员的出现。在本研究中，作物种植顺序影响大田土壤和大豆根际土壤中的细菌多样性和丰富度，而真菌多样性和丰富度对作物种植顺序的影响具有弹性。总之，这些发现有助于推动年度作物和土壤管理实践的决策制定。
