IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN IRRIGATION AND DRAINAGE ENGINEERIG

Abstract

The existing irrigation systems require the adoption of more efficient irrigation techniques for sustainable production in agriculture to increase demands on limited amounts of water supplies for their crops in time. Detail agronomical practice and appropriate method of furrow irrigation system for cabbage crop in Arba Minch climatic condition were not yet studied. Therefore the study was done with the objectives of evaluating the performance of alternate (AFI), fixed (FFI) and conventional furrow irrigation systems (CFI) for cabbage crops in terms of yield, water use efficiency, and different water application indicators. The experimental design was arranged in randomized complete block design (RCBD) with three treatments and three replications. The irrigation water was applied to furrows using siphon from furrow head ditch with an inflow rate of 1 l/s. The collected data were analyzed using WASP2.0 in the probability of a 5% confidence level. In terms of application efficiency (Ea%) and deep percolation loss (Dp%), there were significant differences between the mean results of AFI (77 and 23), FFI (68 and 32), and CFI (67 and 33).The mean storage efficiency (Es %) and distribution efficiency(Ed %) values were 74 and 80 for AFI, 71 and 78 for FFI, and 73 and 82 for CFI, respectively. It represents the insignificant difference in the values of Es and Ed for different methods of furrow irrigation. The yield-based comparison had shown that there was no significant difference between the yield obtained in the AFI (38541.7Kg/ha) and CFI (41666.7Kg/ha), However, there was a significant difference (p<0.05) between the yield of FFI (30208.3Kg/ha) and the CFI system. The mean values of crop water use efficiency (CWUE) were for AFI 32.01kg/m3, FFI 25.09 kg/m3, and CFI 17.30kg/m3 which were significantly different. The mean values of field water use efficiency (FWUE) were for AFI 34.66kg/m3, FFI 27.17kg/m3, and CFI 18.74 kg/m3 showing significant difference between different methods of furrow irrigation. The AFI system was taken as promising for the conservation of water, time, and labor. Therefore.AFI is best method to grow head cabbage.