Growth and yield of lowland rice as influenced by potassium application and cultivation method under alternate wetting and drying water regime

Besides being an essential macronutrient for plant growth, potassium (K) also acts as a stress-relieving agent against various biotic and abiotic stresses, especially water stress. An experiment consisting of three lowland Thai rice varieties (Pathumthani 1, RD57, RD41), two cultivation methods [dry direct seeding (DDS), transplanting (TP)] and four K doses (0, 80, 120,160kgha(-1)) under alternate wetting and drying (AWD) water regime was conducted to investigate the impact of K and cultivation method on lowland rice varieties subjected to AWD. Pathumthani 1 had significantly higher grain yield at the 120kgKha(-1) compared with all other K doses. RD57 and RD41 had maximum grain yield at the 80 and 120kgKha(-1), respectively, which was significantly higher than the control; however, grain yield among different K doses was mostly similar for RD57 and RD41. K application at the rate of 120kgha(-1) for Pathumthani 1 and 80kgha(-1) for RD57 and RD41 could be a feasible option. The performance of DDS and TP was better at the 80 and 120kgKha(-1), respectively. Application of K at the optimum dose with proper selection of variety and cultivation method could help in sustainable rice production.