College of Agronomy/State Key Laboratory of Crop Stress Resistance and High-Efficiency Production, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Yangling Vocational and Technical College, Yangling, Shaanxi, 712100, China.
Sci Total Environ. 2024 Jun 25;931:172714. doi: 10.1016/j.scitotenv.2024.172714. Epub 2024 Apr 26.
Understanding the responses of soybean rhizosphere and functional microbiomes in intercropping scenarios holds promise for optimizing nitrogen utilization in legume-based intercropping systems. This study investigated three cropping layouts under film mulching: sole soybean (S), soybean-maize intercropping in one row (IS), and soybean-maize intercropping in two rows (IIS), each subjected to two nitrogen levels: 110 kg N ha (N110) and 180 kg N ha (N180). Our findings reveal that cropping patterns alter bacterial and nifh communities, with approximately 5 % of soybean rhizosphere bacterial amplicon sequence variants (ASVs) and 42 % of rhizosphere nifh ASVs exhibiting altered abundances (termed sensitive ASVs). Root traits and soil properties shape these communities, with root traits exerting greater influence. Sensitive ASVs drive microbial co-occurrence networks and deterministic processes, predicting 85 % of yield variance and 78 % of partial factor productivity of nitrogen, respectively. These alterations impact bacterial and nifh diversity, complexity, stability, and deterministic processes in legume-based intercropping systems, enhancing performance in terms of yield, nitrogen utilization efficiency, land equivalent ratio, root nodule count, and nodule dry weight under IIS patterns with N110 compared to other treatments. Our findings underscore the importance of field management practices in shaping rhizosphere-sensitive ASVs, thereby altering microbial functions and ultimately impacting the productivity of legume-based intercropping systems. This mechanistic understanding of soybean rhizosphere microbial responses to intercropping patterns offers insights for sustainable intercropping enhancements through microbial manipulation.
了解大豆根际和功能微生物组在间作情景中的响应，有望优化基于豆科植物的间作系统中的氮利用。本研究在覆膜条件下调查了三种种植布局：单作大豆（S）、单作大豆-玉米间作（IS）和双行大豆-玉米间作（IIS），每种布局均设置两个氮水平：110 kg N ha-1（N110）和 180 kg N ha-1（N180）。我们的研究结果表明，种植模式改变了细菌和 nifH 群落，大约有 5%的大豆根际细菌扩增子序列变异体（ASVs）和 42%的根际 nifH ASVs 丰度发生变化（称为敏感 ASVs）。根系特征和土壤性质塑造了这些群落，其中根系特征的影响更大。敏感 ASVs 驱动微生物共现网络和确定性过程，分别预测了 85%的产量方差和 78%的氮部分生产力。这些变化影响了基于豆科植物的间作系统中的细菌和 nifH 多样性、复杂性、稳定性和确定性过程，在 IIS 模式下，与其他处理相比，N110 处理提高了产量、氮利用效率、土地当量比、根瘤数和根瘤干重的性能。我们的研究结果强调了田间管理实践在塑造根际敏感 ASVs 方面的重要性，从而改变了微生物功能，最终影响了基于豆科植物的间作系统的生产力。对大豆根际微生物对间作模式响应的这种机制理解为通过微生物操纵来提高可持续间作提供了见解。
