Water productivity and yield of Paddy Rice cultivation under AWD irrigation management in Pingtung, southern Taiwan

Abstract— Decreasing water input while maintaining grain yield remains a challenge for World to produce rice sustainably. In recent years, the Alternate wetting and Drying Irrigation(AWD)has been developed toward Asian’ farmers. However, the gap observed is the low assessment of its performances, particularly in Taiwan. The aim of this study is to determine whether AWDI management could maintain grain yield with reduced water input. AWD approach experiment field was conducted in National Pingtung University, in Southern Taiwan. A two leaves old rice seedling, TAINAN11 was arranged in a randomized complete block design with five water treatments: AWD2cm, AWD3cm, AWD3cm/w, AWD4cm and AWD5cm with respectively 2cm and 3 cm water depth monitoring by soil hairline cracks; 3cm, 4 cm, and 5cm weekly irrigation. The irrigation regimes were done by AWD technics. The plant water status was assessed through soil water content. Crop growth, grain yield, and water productivity were measured. The results showed that grain yields under AWD3cm, AWD2cm and AWD3cm/w presented the high yield and irrigation water productivity about 0.211, 0.208 and 0.205 respectively. The AWD4cm and AWD5cm despite the high-water depth presented low yield with respectively 3081 Kg/ha and 2604 Kg/ha. The results confirmed also that AWD3cm and more precisely AWD3cm/w could obtain comparable grain yield close to farmers practices with fewer irrigations. These findings suggested that AWD with 3 cm water depth (AWD3cm and AWD3cm/w) could be used for water-saving while maintaining grain yield in paddy rice production