Water use and yield response of tomato as influenced by drip and furrow irrigation

Field experiments were conducted for three years (2002, 2003 and 2004) on sandy loam soil at the Regional Research and Technology Transfer Station, Chiplima, Orissa, India to study the effects of furrow irrigation and variable water supply by drip irrigation on yield and water use of tomato crop. The study was conducted in randomized block design with four treatments having five replications each. The treatments were (i) T1 = drip irrigation at 100% crop evapotranspiration (ETc) replenishment, (ii) T2 = drip irrigation at 80% ETc replenishment, (iii) T3 = drip irrigation at 60% ETc replenishment and (iv) T4 = furrow irrigation at 1.2 IW: CPE (IW = irrigation water of depth 5 cm and CPE = cumulative pan evaporation). Tomato variety Arjun was planted in all the treatments with 90 cm spacing from row to row and 75 cm spacing from plant to plant. In drip irrigation, crops were irrigated at 2-day intervals. Studies on soil moisture distribution revealed that the vertical movement of soil moisture was higher than the horizontal one for different time intervals after application of irrigation for all the drip treatments. However, the moisture distribution pattern indicated that there was maximum extraction of soil moisture from 15-30 cm depth that resulted in obtaining higher values of ETc for said profile layer than for all other layers for all the treatments. Treatment T1 was observed to maintain higher values of moisture content both horizontally and vertically throughout the crop growth period than all other treatments. Because of this reason, the yield of crop was found to be maximal (180.97 q/ha) for the treatment T1 (drip irrigation at 100% ETc replenishment) whereas those for treatments T2, T3 and T4 were 162.77, 145.12 and 156.86 q/ha, respectively. The study reveals that drip irrigation at 100% ETc replenishment in tomato can increase the yield by 15.4%, besides saving 17.9% more costly irrigation water than the conventional furrow irrigation practiced by most of the farmers.