Climate change and declining water resources adversely affect rice production. Conventional continuous flooding in rice cultivation requires high water input, posing challenges under water scarcity and contributing to greenhouse gas (GHG) emissions. Alternate wetting and drying (AWD) is a water‐saving irrigation method that addresses water limitations in flooded cultivation. A Scopus literature search resulted in 1,830 articles, of which 77 were selected for quantitative analysis based on inclusion and exclusion criteria. The critical review revealed that AWD reduces water input, increases water productivity and use efficiency. Physiological adjustments include enhanced indole acetic acid, abscisic acid, and cytokinin regulation, and increased enzymatic activities of sucrose and starch synthases. These changes improve root architecture and gas exchange traits, and facilitate efficient assimilate partitioning to maintain stable grain yield. AWD mitigates GHG emissions, reduces pests and disease incidences. Integration of organic amendments enhances soil health and moisture retention capacity. However, widespread adoption is hindered by weed infestations, sociocultural resistance, and economic risk perceptions. Research gaps include limited integration of weed and nutrient management, uncertain AWD performance under extreme weather events, and yield variations due to agroecological conditions. Addressing these through targeted research, local agricultural policies and farmer‐centric strategies is key to promoting AWD for sustainable rice cultivation.
Velayutham et al. (Wed,) studied this question.