Regulated deficit irrigation for crop production under drought stress. A review

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 RDI-induced 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.

Lower global warming potential and higher yield of wet direct-seeded rice in Central China

“…In our study, the water saving in direct-seeded rice was not so evident because the plots were kept under flooded conditions soon after crop establishment. Some water management practices could be adopted to further save the water input and increase water productivity in directseeded rice, such as rainfed (Zhao et al 2007), alternate wet and dry (Bouman and Tuong 2001), regulated deficit irrigation (Chai et al 2016). Yoshida (1981) reported that 1240 mm was an average water requirement to produce a reasonably good crop of rice.…”

Effect of water application on wine quality and yield in 'Carménère' under the presence of a shallow water table in Central Chile

“…It is important to point out that stem water potential values, measured at midday during the three seasons in the present study, were higher than the threshold proposed by Van Leeuwen et al (2009) Water stress was not found in the present study, not even in the treatment without irrigation. This situation would indicate permanent and effective activity of the vine plants' deep root systems, and that the presence of a shallow water table would permit root water uptake as sub-surface irrigation (Chai et al, 2016). The presence of a shallow water table in Chile has only been described by Fredes et al (2010) for 'Carménère' grapevines (phreatic level depth at 2 m), but this background information has not been considered in most authors' reports.…”

Partial Root-Zone Drying Technique: from Water Saving to the Improvement of a Fruit Quality

“…For explaining the physiological and biochemical background of deficit irrigation methods, including PRD technique, several review papers could be recommended (Costa et al, 2007;Fereres and Soriano, 2007;Ruiz-Sanchez et al, 2010;Sepaskhah and Ahmadi, 2010;Stikić et al, 2010;Du et al, 2015;Chai et al, 2016;Galindo et al, 2017;Kang et al, 2017).…”