Chapter 8 - Silicon improves salinity tolerance in crop plants: Insights into photosynthesis, defense system, and production of phytohormones

Abstract

Silicon (Si) is the second most abundant element found in the earth’s crust and is regarded as a beneficial nutrient for plants. The role of Si ranges from regulation of development to protection of plant species from various abiotic stresses. Salinity is abiotic stress that hampers the growth of crops and causes loss in agricultural productivity. It adversely affects the crop yield by disturbing the osmotic potential and causing ion toxicity, altering gene expression, irregulating endogenous hormonal functions, and restricting photosynthetic activity. Thus it is imperative to overcome the deleterious effects of salinity in plants by adopting suitable methods, that is, selection and breeding approach, engineering and gene modification, advancement in agronomical traits, and provision of exogenous substances to induce salt stress tolerance in plants. Silicon has been considered a significant exogenous substance that plays a multifunctional role in promoting plant vigor and ensuring sustainable yield under salt stress. Its exogenous foliar application has been reported to bring positive changes in plants by regulating molecular, metabolic, and physiological responses under salinity problems. This chapter focuses on the significance and importance of Si in regulating certain physiobiochemical acclimation in plants under salt stress. This study highlights the beneficial role of silicon application in improving salt tolerance and growth of plants under a saline environment which will offer new dimensions of its use in saline agriculture.