Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA; email:
Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Annu Rev Plant Biol. 2019 Apr 29;70:781-808. doi: 10.1146/annurev-arplant-042817-040305.
The ratio of plant carbon gain to water use, known as water use efficiency (WUE), has long been recognized as a key constraint on crop production and an important target for crop improvement. WUE is a physiologically and genetically complex trait that can be defined at a range of scales. Many component traits directly influence WUE, including photosynthesis, stomatal and mesophyll conductances, and canopy structure. Interactions of carbon and water relations with diverse aspects of the environment and crop development also modulate WUE. As a consequence, enhancing WUE by breeding or biotechnology has proven challenging but not impossible. This review aims to synthesize new knowledge of WUE arising from advances in phenotyping, modeling, physiology, genetics, and molecular biology in the context of classical theoretical principles. In addition, we discuss how rising atmospheric CO concentration has created and will continue to create opportunities for enhancing WUE by modifying the trade-off between photosynthesis and transpiration.
植物碳增益与水分利用的比例，即水分利用效率（WUE），长期以来一直被认为是作物生产的关键限制因素，也是作物改良的重要目标。WUE 是一个生理和遗传上复杂的特征，可以在一系列尺度上进行定义。许多组成性状直接影响 WUE，包括光合作用、气孔和叶肉导度以及冠层结构。碳和水分关系与环境和作物发育的各个方面的相互作用也调节 WUE。因此，通过育种或生物技术提高 WUE 已被证明具有挑战性，但并非不可能。本综述旨在综合新的 WUE 知识，这些知识来自表型分析、建模、生理学、遗传学和分子生物学方面的进展，同时考虑到经典理论原理的背景。此外，我们还讨论了大气 CO 浓度的上升如何以及将继续通过改变光合作用和蒸腾作用之间的权衡来创造提高 WUE 的机会。
