Crop establishment-irrigation interactions driven rice (Oryza sativa L.) performance and water productivity

Excessive water use in flooded irrigation systems poses a significant challenge in rice cultivation. Therefore, it is essential to adopt irrigation management techniques that conserve water, enhance water productivity, and address water scarcity. This experiment aimed to evaluate the yield and water productivity of various crop establishment methods combined with different irrigation management techniques. The experiment was designed using a split-plot layout with three replications. The main plots comprised three crop establishment techniques: the System of Rice Intensification (SRI), Direct Seeding (DSR), and Transplanting (TPR). The five irrigation regimes were randomized to the subplots implemented, including: continuous submergence (flooding) up to a depth of 3 cm (I1); irrigation application of 24 L m^- 2 four days after the ponded water had disappeared during crop growth (I2); irrigation application of 24 L m^- 2 four days after the ponded water disappeared until panicle initiation, followed by submergence until the dough stage (I3); irrigation application of 24 L m^- 2 four days after the disappearance of ponded water until flowering, then submergence until the dough stage (I4); and saturation throughout until the dough stage (I5). The Shalimar Rice-4 variety was utilized for the study. The results indicated that the SRI method of crop establishment yielded the highest grain yields of 7.72 t ha^-1 and 7.93 t ha^-1, alongside straw yields of 9.64 t ha^-1 and 9.98 t ha^-1, in the years 2021 and 2022, respectively. Furthermore, the highest total crop water productivity was observed in the saturation treatment compared with continuous flooding. Consequently, the System of Rice Intensification with saturation emerged as the most efficient irrigation strategy, as it retained the highest total crop water productivity under the temperate conditions of Kashmir.