Effects Of Regulated Deficit Irrigation On Water Productivity Of Date Palm (Phoenix Dactylifera L.) In The Arid Environment Of South Iraq

Abstract

Due to the scarcity of water resources in southern Iraq, the use of deficit irrigation scheduling is beneficial for sustainable agricultural development. Therefore, a two-year field experiment was conducted to study the effect of regulated deficit irrigation (RDI) on yield and water productivity (WP) of date palms irrigated with a bubbler irrigation system. Five water systems were used D1, D2, D3, D4, and FI representing 0, 25, 50, 75, and 100% of ETc and applied during two stages: the first stage includes flowering and hababouk, the second stage is the Rutub and Tamer stage they were studied to select the best water system that maximizes yield and WP, the results indicate that RDI strategies saved irrigation water by 5-39%. The highest yield was under full irrigation (FI) and (D4) and as an overall average for the two seasons, at35.1, 35.2 kg.palm-1. The largest decrease in production was recorded in the treatment of D1 by 29% compared to (FI). The highest WP was achieved in treatments D1 and D4, as an overall average for the two seasons, at 0.46 and 0.47 kg.m-3. In conclusion, the palm needs regular irrigation during the year to maintain growth and production, with the possibility of reducing irrigation in the stage of flowering and hababouk and, the Rutub and Tamer. Full irrigation is recommended to achieve the highest yield, and it is also recommended to use the RDI strategy with 0-75% ETc if we consider the benefits of Economic and WP in the study area. Further research in the field of RDI is also recommended to study its effect on the phenological stages of palms.