Abstract:In the context of global climate change, drought has become one of the major abiotic stresses limiting crop yield and quality worldwide, which causes huge losses to the global society, economy and ecology. Hence, it is increasingly critical to enhance the drought resistance of plants. Numerous studies at domestic and abroad have confirmed that silicon can promote plant drought resistance. For example, the application of exogenous silicon can improve water status of plants by affecting the stomatal conductance and changing the transpiration rate; silicon can also improve photosynthesis by regulating stomatal dynamics, synthesizing photosynthetic pigments and promoting photochemical reactions; in addition, silicon can not only balance the absorption and utilization of minerals by plants through osmotic adjustment but also regulate the antioxidant defense system to reduce the oxidative damage of plants under drought stress. Here, we systematically summarize the effects of silicon on plant water utilization, photosynthesis, mineral absorption, antioxidant systems, plant hormone metabolism and related physiological mechanisms under drought stress. It was suggested that the mechanism by which silicon enhances drought resistance of plants should be revealed from the aspects of combined stress and low silicon accumulating plants in the future, so as to provide a scientific basis and lay a theoretical foundation for the rational use of silicon in agroforestry ecosystems to improve production efficiency.
