College of Resources and Environment, Hunan Agricultural University, Changsha, 410128, China.
Institute of Agro-Environment and Ecology, Hunan Academy of Agricultural Sciences, Changsha, 410125, China.
Sci Rep. 2018 Nov 8;8(1):16554. doi: 10.1038/s41598-018-34685-0.
Bacteria, as the key component of soil ecosystems, participate in nutrient cycling and organic matter decomposition. However, how fertilization regime affects the rhizospheric bacterial community of reddish paddy soil remains unclear. Here, a long-term fertilization experiment initiated in 1982 was employed to explore the impacts of different fertilization regimes on physicochemical properties and bacterial communities of reddish paddy rhizospheric soil in Central South China by sequencing the 16S rRNA gene. The results showed that long-term fertilization improved the soil nutrient status and shaped the distinct rhizospheric bacterial communities. Particularly, chemical NPK fertilizers application significantly declined the richness of the bacterial community by 7.32%, whereas the application of manure alone or combined with chemical NPK fertilizers significantly increased the biodiversity of the bacterial community by 1.45%, 1.87% compared with no fertilization, respectively. Moreover, LEfSe indicated that application of chemical NPK fertilizers significantly enhanced the abundances of Verrucomicrobia and Nitrospiraceae, while manure significantly increased the abundances of Deltaproteobacteria and Myxococcales, but the most abundant Actinobacteria and Planctomycetes were detected in the treatment that combined application of manure and chemical NPK fertilizers. Furthermore, canonical correspondence analysis (CCA) and the Mantel test clarified that exchangeable Mg (E-Mg), soil organic carbon (SOC) and alkali-hydrolyzable nitrogen (AN) are the key driving factors for shaping bacterial communities in the rhizosphere. Our results suggested that long-term balanced using of manure and chemical fertilizers not only increased organic material pools and nutrient availability but also enhanced the biodiversity of the rhizospheric bacterial community and the abundance of Actinobacteria, which contribute to the sustainable development of agro-ecosystems.
细菌是土壤生态系统的关键组成部分，参与养分循环和有机物质分解。然而，施肥制度如何影响赤红壤根际细菌群落尚不清楚。本研究采用 1982 年开始的长期施肥试验，通过测序 16S rRNA 基因，探讨不同施肥制度对中南地区赤红壤根际土壤理化性质和细菌群落的影响。结果表明，长期施肥改善了土壤养分状况，塑造了独特的根际细菌群落。特别是，化肥 NPK 的施用显著降低了细菌群落的丰富度，降低了 7.32%，而单独施用有机肥或与化肥 NPK 结合施用有机肥分别显著增加了细菌群落的生物多样性 1.45%和 1.87%，与不施肥相比。此外，LEfSe 表明，化肥 NPK 的施用显著增加了 Verrucomicrobia 和 Nitrospiraceae 的丰度，而有机肥显著增加了 Deltaproteobacteria 和 Myxococcales 的丰度，但在有机肥和化肥 NPK 联合施用的处理中检测到最丰富的放线菌和浮霉菌。此外，典范对应分析（CCA）和 Mantel 检验表明，可交换镁（E-Mg）、土壤有机碳（SOC）和碱解氮（AN）是塑造根际细菌群落的关键驱动因素。我们的结果表明，长期平衡使用有机肥和化肥不仅增加了有机物质库和养分的有效性，而且提高了根际细菌群落的生物多样性和放线菌的丰度，这有助于农业生态系统的可持续发展。
