Water Productivity as a Tool for Deficit Irrigation Strategy to Optimize Watering Requirements for the Production of Chickpea (Cicer arictinum L.) Under Dry Land Conditions of the Northern State, Sudan

Abstract

A field experiment was carried out for two consecutive seasons (2015/16 and 2016/17) on the sandy loam desert soil of New Hamdab Research Station with a view  to investigating the response of deficit irrigation as induced by the water productivity at different growth stages of chickpea (Cicer arictinum L.). Five irrigation treatments were conducted, I₁ (100% crop water requirement throughout the season was considered control, I₂ and I₃ indicated (75% and 50% crop water requirements at crop vegetative growth stage) respectively, where as I₄  and I₅   indicated (75%  and 50% crop water requirements at crop ripening stage) respectively. The full irrigation treatment  and the 75% deficit irrigation treatments at the vegetative and ripening stages showed higher chickpea grain yield, higher number of pods per plant and 100 seed weight. On the other hand the deficit irrigation of 50% crop water requirement applied at the vegetative stage resulted in higher water productivity (0.59 kg/m³) but attaining lower grain yield  with higher deficit irrigation stress index (DISI). Therefore, in order to save irrigation water while keeping high productivity of chickpea under such dry conditions, it is recommended to apply deficit irrigation of 50% crop water requirement at vegetative stage of the crop.