Water Requirement and Crop Coefficient of Medium Seed Size Peanut

Abstract

The water requirement and Crop Coefficient (Kc) of medium seed size peanut were studied on sandy-loam soils (Yasothon soil series) at KhonKaen Field Crops Research Center from October, 2014 to February, 2015. Experimental design was Randomize Complete Block with three replications and five treatments which were 1) Rain-fed condition 2) supplementary drip irrigation with 12.5% of Available Water Capacity (AWC) within 0.50 meter depth 3) supplementary drip irrigation with 25.0% AWC 4) supplementary drip irrigation with 37.5% AWC and 5) supplementary drip irrigation with 50.0% AWC. The results showed that all supplementary drip irrigation treatments gave significant higher yield than that of rain-fed condition treatment. Supplementary drip irrigation with 37.5% of available water capacity gave the highest yield (1,100 kg/rai fresh weight pods and 569 kg/rai dry weight pods respectively). Water requirement throughout growing season was 531 mm. Crop coefficient (Kc) of KK97-44-106 were 0.32 at germination and growth stages, 1.12 at flowering, 1.22 at first pod and seed development, 1.16 at pod and seed filling and 0.79 at seed maturation. Finally, water use efficiency (WUE) was 1.17 mm/kg/rai while the rain-fed condition treatment showed the lowest yield (158 kg/rai fresh weight pods and 79 kg/rai dry weight pods respectively) and WUE was 0.43 mm/kg/rai.