Partial root zone drying method of irrigation: A review

Water availability has been a major constraint in crop production technology across the globe. The agricultural sector has been the largest consumer of fresh water for ages and accounts for about two-thirds of the total fresh water used for human consumption. In the scenario of rapid population growth, the share of fresh water allocated to agriculture would get reduced to a great extent. Therefore, there is the ever-increasing need to use the available water efficiently and precisely. It is a high priority to evolve new irrigation methods so that water use efficiency (WUE) can be maximized through optimum management of available irrigation water. Deficit irrigation (DI) is an optimization strategy that requires crops to intentionally endure a certain level of water deficit. This sometimes leads to a decrease in yield, however, with a significant increase in WUE. Partial root zone drying (PRD) is a modified version of DI, which has been practiced to improve WUE by controlling drought stress. In this method of irrigation, the spatial separation of dry and wet roots is maintained during the entire cropping season. The water stress developed in one part of the root zone generates chemical signals in the form of abscisic acid, which leads to partial closure of stomatal opening. Stomatal closure reduces the rate of transpiration, which in turn increases WUE. This paper is an effort to briefly discuss the concept of PRD and to review some important work carried out across the world.

Automated summary

Water scarcity is a major constraint in crop production worldwide, leading to the need for new irrigation methods to improve water use efficiency. Deficit irrigation and partial root zone drying are two improved methods that enhance water use efficiency by controlling water stress.