[Effects of γ-aminobutyric acid and chlorinated hemin composite coating on seed germination and seedling growth of Psathyrostachys juncea under drought and salt stresses].

chlorinated hemin was the most effective under salt stress. When both compounds were combined, they significantly outperformed individual treatments under combined drought and salt stress, increasing germination rate by 28.7%, germination potential by 70.5%, and enhancing catalase and superoxide dismutase activities by 38.3% and 44.8%, respectively. The pot experiment further demonstrated that seed coating with the combined treatment increased aboveground and belowground biomass by 28.1% and 21.1%, respectively, and improved leaf net photosynthetic rate by 45.6% compared to the naked seeds. These findings suggested that seed coating with a combination of GABA and chlorinated hemin could effectively alleviate drought stress and salt stress, which would provide technological support for grassland restoration.