State Key Laboratory of Wheat and Maize Crop Science, College of Agronomy, Henan Agricultural University, Zhengzhou 450046, PR China.
Wheat Research Center of Henan Academy of Agricultural Sciences, Zhengzhou 450002, China.
Sci Total Environ. 2019 Dec 20;697:134088. doi: 10.1016/j.scitotenv.2019.134088. Epub 2019 Aug 27.
Achieving both high yield and high nitrogen (N) use efficiency (NUE) simultaneously is a current research hotspot in crop production. To investigate approaches for achieving high yield and NUE, field experiments using N fertilizer rates of 0, 120, 180, 240, 300 and 360 kg N ha were conducted to study relationships between yield, N uptake and N efficiency during three wheat growing seasons from 2013 to 2016 in three experimental sites (Shangshui, Kaifeng and Wenxian) in the Huang-Huai Plain. Yield, biomass and N concentrations of plants and soil were determined. The results indicated that increased N application would affect soil N residue and increase NO emission, suitable N application rate (N240-N268) contributed to maintaining soil fertility and reducing NO emission for achieving high yield, high NUE and low NO emission. High plant N accumulation (PNA) during jointing to anthesis had the best correlation coefficient with yield and NUE compared to other growth stages, which contributed to achieving high yield and NUE simultaneously. The dry matter produced by a unit of N was defined as N productivity, such as plant N net phase productivity (PNPn) and leaf N productivity (LNP). High PNPn during jointing to anthesis was significantly related to both yield and NUE. The LNP indicator (i.e. photosynthetic N use efficiency, PNUE) in the flag showed significant correlation with both yield and NUE after booting under high PNA levels. These results suggest that PNPn and PNUE could combine high yield and high NUE under high PNA conditions. Besides, to match soil N supply to plant N demand, optimum soil nitrate N accumulation and alkali-hydrolysable N (AHN) content ranges were determined. This study provides a theoretical basis to achieve high yield, high NUE and low NO emission for N management in wheat field production.
在作物生产中，同时实现高产和高氮（N）利用效率（NUE）是当前的研究热点。为了研究实现高产和 NUE 的方法，本研究于 2013 年至 2016 年在黄淮海平原的三个试验点（商水、开封和文县）进行了三个小麦生长季的田间试验，设置了 0、120、180、240、300 和 360 kg N ha 的氮肥用量。测定了产量、生物量和植株及土壤的氮浓度。结果表明，增加氮肥用量会影响土壤氮残留，增加 NO 排放，适宜的施氮量（N240-N268）有助于维持土壤肥力，减少 NO 排放，从而实现高产、高 NUE 和低 NO 排放。与其他生育期相比，拔节至开花期的高植株氮积累（PNA）与产量和 NUE 的相关系数最好，有助于同时实现高产和 NUE。单位氮生产的干物质定义为氮生产力，如植株氮净相生产力（PNPn）和叶片氮生产力（LNP）。拔节至开花期的高 PNPn 与产量和 NUE 显著相关。在高 PNA 水平下，抽穗后旗叶的 LNP 指标（即光合 N 利用效率，PNUE）与产量和 NUE 显著相关。这些结果表明，在高 PNA 条件下，PNPn 和 PNUE 可以结合高产和高 NUE。此外，为了使土壤氮供应与植株氮需求相匹配，确定了最佳的土壤硝态氮积累和碱解氮（AHN）含量范围。本研究为实现小麦田间生产中高产、高 NUE 和低 NO 排放的氮管理提供了理论依据。
