Research Article
Omar Abdulla
Abstract
Fifteen non-weighing reinforced concrete lysimeters were used to grow alfalfa (Mcdicago sativa) and grass (Cynodondactylon) as a reference crops, and date palm (Phoenix dactylifera L.) as experimental crop to obtain the daily water requirements and crop coefficient throughout productive cycle of date palm. The experimental site was located at the experimental station of the Centre for Date Palm and Dates in Al-Hassa, Saudi Arabia on a sandy loam textured soil. The results showed that estimated potential evapotranspiration of alfalfa and grass crops throughout the experimental period were approximately 2185 and 2068 mm, with a daily average of 5.98 and 5.66 mm per day, respectively. The date palm evapotranspiration increased from 3.09 mm/day in February at pollination stage to 8.25 mm/day in July at fruit maturity stage, and then dipped to 5.42 mm/day in September at the end of harvest. The volumetric palm water requirements per day fell between 87 and 297L during January and July months, respectively with a daily average of 182 L through the whole year depending mostly on climatic conditions and quality of the irrigation water. The date palm crop coefficient was not constant throughout its productive cycle and it ranged from 0.74 to 0.91 according to crop growth stages. The average crop coefficient for the date palm productive cycle through the whole year was 0.83.