Sodium nitroprusside pellets enhance rice seed germination and seedling development under low-temperature conditions

Low temperature stress seriously restricts the seedling establishment and yield stability of direct-seeded rice. In this study, we proposed sodium nitroprusside (SNP), a nitric oxide donor, as a functional component for seed pelleting to improve the low temperature resistance of rice. SNP pelleting treatment significantly increased seed germination, vigour and seedling growth at low temperature. Physiological mechanism analysis showed that SNP enhanced the antioxidant system (key enzyme activity and non-enzymatic antioxidant content), reduced the oxidative damage index, increased α-amylase activity and soluble sugar and protein contents, and promoted energy supply. Hormone detection found that SNP treatment increased gibberellin and reduced abscisic acid levels, which was beneficial to germination. In summary, SNP pelleting can synergistically enhance the low temperature adaptability of rice through multiple pathways and provide an effective technical approach for stable yield of direct seeded rice under low temperature stress.