IPADS (INTA-CONICET), Ruta 226 Km 73.5, Balcarce, Argentina.
Facultad de Ciencias Agrarias, Universidad Nacional de Mar del Plata, Ruta 226 Km 73.5, Balcarce, Argentina.
J Exp Bot. 2023 Sep 2;74(16):4825-4846. doi: 10.1093/jxb/erad269.
Adequate management of N supply, plant density, row spacing, and soil cover has proved useful for increasing grain yields and/or grain yield stability of rainfed crops over the years. We review the impact of these management practices on grain yield water-related determinants: seasonal crop evapotranspiration (ET) and water use efficiency for grain production per unit of evapotranspired water during the growing season (WUEG,ET,s). We highlight a large number of conflicting results for the impact of management on ET and expose the complexity of the ET response to environmental factors. We analyse the influence of management practices on WUEG,ET,s in terms of the three main processes controlling it: (i) the proportion of transpiration in ET (T/ET), (ii) transpiration efficiency for shoot biomass production (TEB), and (iii) the harvest index. We directly relate the impact of management practices on T/ET to their effect on crop light interception and provide evidence that management practices significantly influence TEB. To optimize WUEG,ET,s, management practices should favor soil water availability during critical periods for seed set, thereby improving the harvest index. The need to improve the performance of existing crop growth models for the prediction of water-related grain yield determinants under different management practices is also discussed.
多年来，充分管理氮供应、植物密度、行间距和土壤覆盖已被证明有助于提高雨养作物的籽粒产量和/或籽粒产量稳定性。我们回顾了这些管理措施对与水分有关的籽粒产量决定因素的影响：季节性作物蒸散量（ET）和单位蒸散水量的籽粒生产水分利用效率（WUEG,ET,s）。我们强调了大量关于管理措施对 ET 影响的相互矛盾的结果，并揭示了 ET 对环境因素响应的复杂性。我们根据控制 WUEG,ET,s 的三个主要过程（i）蒸腾作用在蒸散作用中的比例（T/ET）、（ii）用于地上部生物量生产的蒸腾效率（TEB）和（iii）收获指数，分析了管理措施对 WUEG,ET,s 的影响。我们将管理措施对 T/ET 的影响与它们对作物光截获的影响直接联系起来，并提供了管理措施显著影响 TEB 的证据。为了优化 WUEG,ET,s，管理措施应在种子形成的关键时期有利于土壤水分供应，从而提高收获指数。还讨论了需要改进现有的作物生长模型，以预测不同管理措施下与水分有关的籽粒产量决定因素。
