Agron. Sustain. Dev. DOI 10.1007/s13593-015-0338-6
Qiang Chai1,3 & Yantai Gan2 & Cai Zhao1,3 & Hui-Lian Xu5 & Reagan M. Waskom4 & Yining Niu1,2 & Kadambot H. M. Siddique6
1Gansu Provincial Key Laboratory for Aridland Crop Sciences, Gansu Agricultural University, Lanzhou 730070, Gansu, China
2Agriculture and Agri-Food Canada, Swift Current Research and
Development Centre, Saskatchewan S9H 3X2, Canada
3College of Agronomy, Gansu Agricultural University,Lanzhou 730070, Gansu, China
4Colorado Water Institute, Colorado State University, Fort
Collins, CO 80523, USA
5International Nature Farming Research Center, 5632-1 Hata,
Matsumoto City, Nagano 390-1401, Japan
6The UWA Institute of Agriculture, The University of Western
Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
Accepted: 6 November 2015
The Author(s) 2015. This article is published with open access at SpringerLink.com
Abstract Agriculture consumes more than two thirds of the total freshwater of the planet. This issue causes substantial conflict in freshwater allocation between agriculture and other economic sectors. Regulated deficit irrigation (RDI) is key technology because it helps to improve water use efficiency. Nonetheless, there is a lack of understanding of the mechanisms with which plants respond to RDI. In particular, little is known about how RDI might increase crop production while reducing the amount of irrigation water in real-world agriculture. In this review, we found that RDI is largely implemented through three approaches: (1) growth stage-based deficit irrigation, (2) partial root-zone irrigation, and (3) subsurface dripper irrigation. Among these, partial root-zone irrigation is the most popular and effective because many field crops and some woody crops can save irrigation water up to 20 to 30 % without or with a minimal impact on crop yield. Improved water use efficiency with RDI is mainly due to the following: (1) enhanced guard cell signal transduction network that decreases transpiration water loss, (2) optimized stomatal control that improves the photosynthesis to transpiration ratio, and (3) decreased evaporative surface areas with partial root-zone irrigation that reduces soil evaporation. The mechanisms involved in the plant response to RDIinduced water stress include the morphological traits, e.g., increased root to shoot ratio and improved nutrient uptake and recovery; physiological traits, e.g., stomatal closure, decreased leaf respiration, and maintained photosynthesis; and biochemical traits, e.g., increased signaling molecules and enhanced antioxidation enzymatic activity.
Keywords Agriculturalwater . Drought stress . Irrigation management . Leaf water potential . Partial root-zone drying Stomatal conductance . Stress-tolerant mechanism . Water deficit