THE IMPACT OF ALTERNATE FURROW IRRIGATION ON WATER PRODUCTIVITY AND YIELD OF POTATO AT SMALL SCALE IRRIGATION, EJERE WEREDA, WEST SHOA, ETHIOPIA

Abstract

As a result of water resource shortage and the need for food self-sufficiency in Ethiopia, it has become essential to improve the productivity. In this study, an attempt was made to evaluate the impact of alternate furrow irrigation technique on yield and water productivity. Alternate furrow irrigation versus every furrow, fixed furrow and farmer practice (open-ended and unstructured furrow) were evaluated at full crop water requirement. The experimental design used was randomized complete block design with four treatment replicated five times. Results obtained revealed that average water application efficiency of alternate furrow irrigation was 85% which was high as compared to other irrigation methods at all irrigation events. Average application efficiencies of ever furrow irrigation, fixed furrow irrigation and farmer practice were 61.5%, 73.4% and 42% respectively. The average distribution uniformity of alternate furrow irrigation and every furrow irrigation methods were 89.3% and 85.3% respectively, which showed no significant difference between the two methods. However, average distribution uniformity of fixed furrow irrigation was 75.4%, which showed significant difference between alternate furrow and fixed furrow irrigation methods. Farmer practice showed poor water distribution uniformity of 63.8%. Alternate furrow irrigation method produced total tuber yield of 33198kg/ha which showed insignificant difference as compared with that obtained under every furrow irrigation ( 33369kg/ha). Total tuber yield harvested from fixed furrow irrigation and farmer practice were 30177kg/ha and 30098kg/ha respectively, which showed insignificant difference between the two methods. High marketable yield of 32667.8kg/ha was recorded from alternate furrow irrigation whereas, low marketable yield of 28266.7kg/ha was recorded from farmer practice. Water productivity of 11.2kg/m3,10.7kg/m3,6.1kg/m3and 4.1kg/m3 were produced under alternate furrow, fixed furrow, and every furrow and farmer practice respectively. It was found that alternate furrow irrigation method saved 50% of water as compared with every furrow and 68.4% as compared with farmer practice. Therefore, it is recommended alternate furrow irrigation method with appropriate irrigation interval is suitable irrigation method; for humid climate where soil is dominated by clay soil and water is liming factor for potato crop production.