Effects of nitrogen fertilization on the rhizosphere priming
Effects of nitrogen fertilization on the rhizosphere priming
复制标题
氮肥对根际启动的影响
DOI：
10.1007/s11104-021-04872-6
复制
发表时间：
2021-02-21
期刊：
影响因子：
4.9
通讯作者：
Gunina, Anna
中科院分区：
文献类型：
--
作者：
Jiang, Zhenhui;Liu, Yizhen;Gunina, Anna
背景与目的氮素输入调节根际引发效应（RPE）;然而，在增加施肥量下引发的大小和驱动机制仍不清楚。（对照，75（N75），150（N150），225（N225），和300（N300）kg N ha−1）施用于植物（玉米）-土壤（水稻）系统，并在喇叭口期监测RPE结果在有植物存在的情况下，N的加入使土壤CO2排放量降低了21.1-49.3%。在对照-N150中，由于低微生物C：N不平衡，RPE随着N输入而下降，由于低微生物N开采和微生物活化以及高微生物代谢效率（MME）而降低酶活性。相比之下，在N150 − N300中，随着N输入，RPE增加，这归因于微生物C：N失衡导致低MME，而不是促进微生物N开采或微生物活化机制。微生物的C：N不平衡是微生物和plants.ConclusionsThus之间的N竞争的结果，酶的活动和MME的组合介导N-调节RPE，而N竞争驱动RPE机制的切换。
Background and aimsIt is known that nitrogen (N) input modulates the rhizosphere priming effect (RPE); however, the magnitude and driving mechanisms of priming under increasing rates of fertilizer application remain unclear.Methods15N-urea (control, 75 (N75), 150 (N150), 225 (N225), and 300 (N300) kg N ha−1) was applied to a plant (maize)-soil (rice paddy) system and the RPE was monitored during the trumpet period (the most active stage) of plant growth.ResultsAddition of N decreased soil-derived CO2emission by 21.1–49.3% in the presence of plants. The RPE declined following N input in the control−N150 as a result of low microbial C:N imbalance, which decreased enzyme activities due to low microbial N mining and microbial activation, and high microbial metabolic efficiency (MME). In contrast, the RPE increased following N input in the N150 − N300, which was attributed to the high microbial C:N imbalance causing low MME, rather than the promotion of microbial N mining or microbial activation mechanisms. The microbial C:N imbalance was the result of N competition between microorganisms and plants.ConclusionsThus, the combination of enzyme activities and MME mediates N-regulated RPE, while N competition drives the switching of RPE mechanisms.