DRIP IRRIGATION SCHEDULING BASED ON CROP EVAPOTRANSPIRATION FOR TOMATO AT ARBA MINCH, SOUTHERN ETHIOPIA

Abstract

Shortage of water represents one of the most limiting factors in crop production worldwide due to this Limited water for crop production in semi-arid regions of the country makes growers seek ways to save water by increasing irrigation efficiencies. An experiment was conducted to enhance tomato yield and yield component under drip irrigation scheduling in water scarce area of Arba Minch area. For this investigation five levels of irrigation water applications were used. The first treatment (T1) was applied 100% of Moisture allowable deficit used as control treatment. The second, third, fourth & fifth treatments (T2, T3, T4 & T5) were given 75%, 50%, 25& 0% of Moisture allowable deficit, respectively, as deficit irrigation treatments. Six-week-old seedlings of tomato, which have developed eight leaves, were transplanted on experimental plots with three replications. The treatments were assigned to the plots randomly. Irrigation water was applied with drip systems based on indirect soil moisture measurement by water budget method. Irrigation was scheduled when 40% of TAW was depletion at the control treatment, and deficit treatments were receiving based on their percent of deficit levels relative to the full supplied treatment. Generally, the study indicated that, water deficit is a practical technique to save large amounts of irrigation water with a relative yield reduction and supplying tomato crop up to 25% water deficit during the whole growing season has no significant difference with control treatment on productivity of tomato production. Therefore, Drip irrigation applied with75% of MAD was found to be the alternative irrigation amount for ArbaMinch.