Instituto de Investigaciones en Biodiversidad y Biotecnología, CONICET- Fundación para Investigaciones Biológicas Aplicadas (INBIOTEC, CONICET-FIBA), Vieytes 3103, B7602FCK Mar del Plata, Buenos Aires, Argentina.
Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany.
FEMS Microbiol Ecol. 2021 Mar 8;97(3). doi: 10.1093/femsec/fiab007.
Soil microbial communities are key players of ecosystem processes and important for crop and soil health. The Humid Pampas region in Argentina concentrates 75% of the national soybean production, which is based on intensive use of agrochemicals, monocropping and no-till. A long-term field experiment under no-till management in the southeast of the Argentinean Pampas provides a unique opportunity to compare soybean under monocropping with cultivation including alternating cover crops or in a three-phase rotation. We hypothesized that cropping regimes and season affect soil microbial community composition and diversity. Amplicon sequencing of 16S rRNA genes and internal transcribed spacer fragments showed a stronger microbial seasonal dynamic in conservation regimes compared to monocropping. In addition, several bacterial (e.g. Catenulispora, Streptomyces and Bacillus) and fungal genera (e.g. Exophiala) with cropping regime-dependent differential relative abundances were identified. Despite a temporal shift in microbial and chemical parameters, this study shows that long-term cropping regimes shaped the soil microbiota. This might have important implications for soil quality and soybean performance and should therefore be considered in the development of sustainable agricultural managements.
土壤微生物群落是生态系统过程的关键参与者，对作物和土壤健康至关重要。阿根廷的湿润潘帕斯地区集中了全国 75%的大豆产量，其生产方式主要依赖于农业化学品的大量使用、单一作物种植和免耕。在阿根廷潘帕斯东南部进行的一项长期免耕管理田间试验为比较单一种植大豆与包括交替覆盖作物或三阶段轮作的种植方式提供了独特的机会。我们假设种植制度和季节会影响土壤微生物群落的组成和多样性。16S rRNA 基因和内部转录间隔区片段的扩增子测序结果表明，与单一种植相比，保护制度下的微生物季节性动态更强。此外，还鉴定出了一些与种植制度相关的具有差异相对丰度的细菌（例如 Catenulispora、链霉菌和芽孢杆菌）和真菌属（例如外瓶霉属）。尽管微生物和化学参数存在时间上的变化，但本研究表明，长期的种植制度塑造了土壤微生物群。这可能对土壤质量和大豆产量有重要影响，因此在制定可持续农业管理措施时应予以考虑。
