Rice cultivation to cope with drought situation by alternate wet and dry (awd) water management system: case study of ratchaburi province, thailand

Abstract

Alternate wet and dry (AWD) system is an interesting water management system that has been widely promoted to replace continuous flooding (CF) system as an effective water saving technique for rice cultivation. This study was conducted in wet season of 2015 and dry season of 2016 in Ratchaburi Province, Thailand, with a randomised block design to estimate and compare the water used in rice cultivation and grain yield between AWD and CF systems. Water level controlling in rice field of AWD was incomplete in wet season experiment due to rainfall interference, but it was complete in the dry season experiment. It was found (non-significantly) that AWD used less water in rice cultivation than CF. It reduced water use by average about8.13 % for the stages of transplanting to harvesting and 7.51 % for the stage of land preparation to harvesting. Dry field allowing of AWD has positive effects to tiller, panicle numbers and productivity which it increased grain yield by 2.42 % as compared to CF. This increase of grain yield can only be found in complete AWD (AWD in dry season). AWD also found significantly increased water productivity in both wet and dry seasons as compared to CF. Our result suggested that in the case study at Ratchaburi, although less water used in complete AWD than in CF, it was still not significant to show the effective of water used in the incomplete AWD system. More investigation in water consumption with no rainwater interfering is recommended.