Sulphur coated urea increases drought tolerance in rice by improving photosynthetic efficiency, antioxidant performance, osmolyte synthesis, and nitrogen use efficiency

ABSTRACT Drought stress (DS) significantly threatens crop productivity and global food security. The intensity of DS is continuously soaring due to climate change, which is causing a substantial reduction in plant productivity. Coated fertilizers emerged as an excellent strategy to improve crop productivity and reduce the toxic effects of abiotic stresses. Thus, this study determined the role of coated urea fertilizers in mitigating DS in rice (Oryza sativa L.) plants. The experiment comprised different DS levels: Control (100% field capacity: FC), 70% FC, and 50% FC; and different types of coated urea: Control, normal urea (NU), Zn-coated urea (ZCU), S-coated urea (SCU). Drought stress decreased grain yield by 43.7%, enhanced electrolyte leakage, hydrogen peroxide and malondialdehyde (+151%, +105% and +217%, respectively), and reduced chlorophyll-a, total soluble proteins and free amino acids by -84%, -85% and -69%, respectively. However, SCU application in DS augmented grain yield by ~46%, boosted ascorbic acid activity (+119%) and agronomic N use efficiency (67.12%). Therefore, applying SCU could be an effective strategy for mitigating the adverse impacts of drought and enhancing rice productivity.