Yield and water productivity of rice as influenced by crop establishment and irrigation methods under temperate environment

This study compares direct-seeded rice (DSR) with transplanted rice under three different irrigation methods: conventional flooding, saturation, and alternate wetting and drying. The findings indicate that DSR outperforms transplanted rice in several key aspects. Specifically, DSR exhibited a greater number of tillers (635-650) and panicles (510-529) m^{- 2}, along with lower spikelet sterility (9.9-10.8%). Grain yield ranged from 6.69 to 7.8 t ha^-1 for DSR, surpassing that of transplanted rice, which yielded between 5.59 and 6.18 t ha^-1. Moreover, DSR demonstrated 11-25% higher water productivity, highlighting its greater efficiency in water usage. Economic analysis revealed that DSR also offered superior returns, with a profit per rupee invested of 2.2, compared to 1.48 for transplanted rice. While irrigation method did not significantly impact growth or yield, conventional flooding led to a 28% reduction in water productivity compared to the saturation method and a 25% reduction compared to the alternate wetting and drying method. In terms of benefit-cost ratio, while the differences were modest, the saturation method recorded slightly higher values. Overall, the study indicates that adopting DSR with either the saturation or alternate wetting and drying irrigation methods can lead to higher yields, improved economic returns, and increased water productivity in temperate environments, positioning it as a more sustainable and efficient alternative to transplanted rice cultivation.