Response of Tomato to Deficit Irrigation at Ambo, Ethiopia

Abstract

Deficit irrigation is a recent innovative approach of  water-saving method that cut down irrigation amounts and increase water productivity. The two years research study was conducted to evaluate the effects of deficit irrigation levels and furrow types on fruit yield and water productivity of Tomato at Ambo Plant Protection Research Center. The experiment was laid out in randomized complete block design with a factorial arrangement involving three replications. The treatments comprised of three furrow type (i.e Alternate furrow irrigation, fixed furrow irrigation and conventional furrow irrigation) and three irrigation deficit levels (i.e. 50 % ETc, 75% ETc and 100 % Etc.). From the over year data analysis 100 % ETc irrigation level has a 6.94 % and 15.91 % yield increment as compared to 75 % ETc and 50 % ETc levels respectively. Also a 9.9 % and 18.15 % fruit yield reduction were recorder from alternate furrow and fixed furrow irrigation as compared to treatment receiving conventional furrow irrigation type. Moreover, maximum water productivity of 26.86 kg/m³ was recorded from 50 % ETc with alternate furrow irrigation  and the minimum value 8.82 kg/m³ was recorded at full irrigation (100% ETc) application with conventional furrow irrigation system. The  statistical analysis showed that, there was a significant difference on tomato fruit yield subjected to the furrow system as well as different deficit  irrigation levels at (p<0.05). Tomato fruit yield obtained from alternate furrow irrigation system was statistically at par with conventional furrow irrigation system and fixed furrow irrigation. But fixed furrow irrigation system has a significant different with that of conventional furrow irrigation system. Also yield obtained with the application of 75 % ETc irrigation level was statistically at par with 100 % ETc level and 50 % ETc but, application of 50 % ETc deficit level was significantly different from 100 % ETc level. Result obtained on water productivity shows a significant difference with furrow system and deficit application levels at (p<0.05). Application of 75 % ETc level saved 25 % water applied as compared to 100 % ETc level without a significant fruit yield reduction with a better water productivity value. In the case of furrow irrigation, alternate furrow irrigation system saved about half of the water applied as compared to conventional furrow irrigation or farmers practice without a significant fruit yield difference with better water productivity value. Therefore, 75 % ETc estimated deficit level and  alternate furrow irrigation system is recommended for the study area.

Keywords: Deficit irrigation, Alternate furrow, Water productivity and Tomato