Tuning water-use efficiency and drought tolerance in wheat using abscisic acid receptors

First author: Ryosuke Mega; Affiliations: Tottori University (鸟取大学): Tottori, Japan

Corresponding author: Masanori Okamoto

Water availability is a key determinant of terrestrial plant productivity. Many climate models predict that water stress will increasingly challenge agricultural yields and exacerbate (使恶化) projected food deficits. To ensure food security and increase agricultural efficiency, crop water productivity must be increased. Research over past decades has established that the phytohormone abscisic acid (ABA) is a central regulator of water use and directly regulates stomatal opening and transpiration. In this study, we investigated whether the water productivity of wheat could be improved by increasing its ABA sensitivity. We show that overexpression of a wheat ABA receptor increases wheat ABA sensitivity, which significantly lowers a plant’s lifetime water consumption. Physiological analyses demonstrated that this water-saving trait is a consequence of reduced transpiration and a concomitant increase in photosynthetic activity, which together boost grain production per litre of water and protect productivity during water deficit. Our findings provide a general strategy for increasing water productivity that should be applicable to other crops because of the high conservation of the ABA signalling pathway.

水分利用是陆地植物生殖的关键决定因素。许多气候模型预测水分胁迫将会持续威胁农业产量，并且加剧粮食的短缺状况。为了确保粮食安全，提高农业效率，我们必须想办法增加作物的水分生产力。过去数十年的研究结果显示脱落酸ABA是调控水分使用的核心组份，能够直接调控气孔开放和植物蒸腾。本文中，作者研究了是否能够通过增加小麦对ABA的敏感性来提高小麦的水分生产力。研究显示过表达一个小麦ABA受体增加了小麦对ABA的敏感性，显著降低了植株一生的用水量。生理分析显示这种节水性状源自于植株蒸腾作用的减少和光合活性的增强，二者同时作用增加了每升水所能产生的籽粒产量，并且能够在水分缺失的条件下保证产量。本文的研究结果为增加水分生产力提供了一个可行的方法，并且由于ABA信号通路在植物中高度保守，所以该方法应该能够被应用于其它作物中。

doi: https://doi.org/10.1038/s41477-019-0361-8

Journal: Nature Plants

First Published: February 08, 2019