β-sitosterol and Glycine Betaine: A Powerful Duo for Enhancing Lupinus Drought Resistance

Drought stress represents a considerable risk to global agricultural yield, requiring novel strategies to alleviate its detrimental effects on agriculture. This research examines the impact of β-sitosterol and glycine betaine on the resilience of Lupinus terms (lupine) plants under drought circumstances by enhancing antioxidative defense mechanisms, increasing secondary metabolite synthesis, and facilitating osmolyte accumulation. Under drought stress, Lupinus plants showed reduced growth and elevated oxidative stress indicators malondialdehyde and H2O2. The combination of β-sitosterol and glycine betaine significantly enhanced plant development, demonstrated by improved photosynthesis and biomass of roots and shoots, with reduced oxidative stress. This improvement was ascribed to increased antioxidative enzymes, like catalase, superoxide dismutase, peroxidase, glutathione reductase, and ascorbate peroxidase, which jointly decreased reactive oxygen species levels and averted oxidative damage. Moreover, β-sitosterol and glycine betaine markedly increased the synthesis of osmolytes and secondary metabolites, allowing lupine plants to maintain cellular turgor and osmotic equilibrium under drought conditions, hence enhancing stress tolerance. In summary, our results provide significant insights into sustainable methods for improving crop resistance to drought, with potential agricultural applications to mitigate the detrimental impacts of climate change on crops.