Effects of Irrigation with Sodium Nitroprusside on Physiological Characteristics of Soybean under Drought Stress.

Background: Although it is a key soybean-producing region, northeast China frequently faces drought. Drought severely affects soybean growth, development and even leads to yield reduction. Methods: Sand cultivation method was employed to investigate the changes in malondialdehyde (MDA) content, nitric oxide (NO) content and individual leaf area of drought-tolerant soybean variety Heinong 44 (HN44) and drought-sensitive soybean variety Heinong 65 (HN65) under drought stress during the flowering stage, with different concentrations of sodium nitroprusside (SNP) used for irrigation. Result: The NO and MDA contents of HN44 and HN65 leaves rose in response to drought stress, MDA content in HN44 and HN65 leaves was noticeably elevated, the individual leaf area showed a downward trend. Irrigation with SNP further increased NO accumulation and reduced membrane lipid peroxidation in the leaves, with the best effect observed at a concentration of 1000 μmol·g^-1. In practical production, SNP can be used to alleviate membrane lipid peroxidation damage in soybean leaves and improve soybean drought resistance when encountering drought. [ABSTRACT FROM AUTHOR]