COMPARISON OF DRIP AND FURROW IRRIGATION METHODS UNDER DEFICIT IRRIGATION AND MULCHING ON GROWTH, YIELD AND WATER PRODUCTIVITY OF COMMON BEANS (PHASEOLUS VULGARIS) IN CENTRAL RIFT VALLY OF ETHIOPIA

Abstract

Water saving in agriculture intends to raise the water utilization rates and water use efficiency resulting in higher economic yield on irrigated farm land with a minimum input of water. An experiment was conducted on the comparative study of drip and furrow irrigation methods under deficit irrigation and mulching on growth, yield and water productivity of common bean in Central Rift Valley of Ethiopia. The experimental design of the trial was split plot design in RCBD with three replications, in which the irrigation methods (Furrow and Drip) were used as main plot and the four irrigation amounts (100%ETc, 85%ETc, 70%ETc and 55%Etc) together with the three mulching techniques(no mulch, straw and plastic mulch) were used as sub-plot. The results revealed that the drip irrigation method had saved 33.6% of water and gave 16% more yield as compared to that of furrow irrigation method. The maximum yield of 3.19 ton/ha was recorded from 100%ETc with plastic mulch treated in drip irrigation method; whereas the minimum yield of 1.17 ton/ha was recorded from 55%ETc with no mulch treated in furrow irrigation method. Higher crop and irrigation water use efficiency of about 0.85 kg/m3 and 0.77 kg/m3 was obtained from 55%ETc with plastic mulch treated in drip irrigation method respectively. The present study suggests that, in water scarce area, farming community can adopt drip irrigation method with 70%ETc or furrow irrigation with 85%ETc under plastic mulch respectively. However, if there is enough amount of water, one can use drip irrigation method with full irrigation under plastic mulch instead of furrow and drip irrigation methods with full irrigation under no mulch.