Key Laboratory of Ecosystem Carbon Source and Sink, China Meteorological Administration (ECSS-CMA), Nanjing University of Information Science and Technology, Nanjing, Jiangsu, China.
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science and Technology, Nanjing, Jiangsu, China.
Appl Environ Microbiol. 2023 Apr 26;89(4):e0018023. doi: 10.1128/aem.00180-23. Epub 2023 Apr 6.
Ethylenediurea (EDU) can effectively mitigate the crop yield loss caused by ozone (O), a major, phytotoxic air pollutant. However, the relevant mechanisms are poorly understood, and the effect of EDU on soil ecosystems has not been comprehensively examined. In this study, a hybrid rice variety (Shenyou 63) was cultivated under ambient O and sprayed with 450 ppm EDU or water every 10 days. Real time quantitative polymerase chain reaction (RT-qPCR) showed that EDU had no significant effect on the microbial abundance in either rhizospheric or bulk soils. By applying both metagenomic sequencing and the direct assembly of nitrogen (N)-cycling genes, EDU was found to decrease the abundance of functional genes related to nitrification and denitrification processes. Moreover, EDU increased the abundance of genes involved in N-fixing. Although the abundance of some functional genes did not change significantly, nonmetric multidimensional scaling (NMDS) and a principal coordinates analysis (PCoA) suggested that the microbial community structure involved in N cycling was altered by EDU. The relative abundances of -and -harboring microbial genera in the rhizosphere responded differently to EDU, suggesting the existence of functional redundancy, which may play a key role in sustaining microbially mediated N-cycling under ambient O. Ethylenediurea (EDU) is hitherto the most efficient phytoprotectant agent against O stress. However, the underlying biological mechanisms of its mode of action are not clear, and the effects of EDU on the environment are still unknown, limiting its large-scale application in agriculture. Due to its sensitivity to environmental changes, the microbial community can be used as an indicator to assess the environmental impacts of agricultural practices on soil quality. This study aimed to unravel the effects of EDU spray on the abundance, community structure, and ecological functions of microbial communities in the rhizosphere of rice plants. Our study provides a deep insight into the impact of EDU spray on microbial-mediated N cycling and the structure of N-cycling microbial communities. Our findings help to elucidate the mode of action of EDU in alleviating O stress in crops from the perspective of regulating the structure and function of the rhizospheric soil microbial community.
乙二脲 (EDU) 可有效减轻臭氧 (O) 造成的作物减产，臭氧是一种主要的、对植物有毒的空气污染物。然而，其相关机制尚不清楚，EDU 对土壤生态系统的影响也尚未得到全面研究。在这项研究中，以杂交水稻品种（Shenyou 63）为研究对象，在大气 O 浓度下培养并每隔 10 天叶面喷施 450 ppm 的 EDU 或水。实时定量聚合酶链反应（RT-qPCR）显示，EDU 对根际和非根际土壤中的微生物丰度均无显著影响。通过同时应用宏基因组测序和氮（N）循环基因的直接组装，发现 EDU 降低了硝化和反硝化过程相关功能基因的丰度。此外，EDU 增加了固氮基因的丰度。虽然一些功能基因的丰度没有明显变化，但非度量多维尺度分析（NMDS）和主坐标分析（PCoA）表明，EDU 改变了与 N 循环有关的微生物群落结构。根际中与 - 和 - 相关的微生物属的相对丰度对 EDU 的响应不同，表明存在功能冗余，这可能在维持大气 O 下微生物介导的 N 循环中发挥关键作用。乙二脲（EDU）是迄今为止最有效的抗臭氧胁迫植物保护剂。然而，其作用模式的潜在生物学机制尚不清楚，EDU 对环境的影响也尚不清楚，这限制了其在农业中的大规模应用。由于其对环境变化的敏感性，微生物群落可用作评估农业实践对土壤质量的环境影响的指标。本研究旨在揭示 EDU 喷雾对水稻根际微生物群落丰度、群落结构和生态功能的影响。本研究深入了解了 EDU 喷雾对微生物介导的 N 循环和 N 循环微生物群落结构的影响。我们的研究结果有助于从调节根际土壤微生物群落结构和功能的角度阐明 EDU 缓解作物臭氧胁迫的作用模式。
