ABSTRACT
Proline (Pro) is one of the most extensively dispersed harmonious solutes which accrues in plants during antagonistic abiotic constraints and acts as a significant protagonist in plant tolerance to stress. Generally Pro transport occurs between cytosol, chloroplasts and mitochondria due to its organized metabolism. It also preserves redox-potential for metabolism during abiotic stress. Pro catabolism in the mitochondria is linked to oxidative respiration and controls dynamism to continue the growth of plants next to stress. Pro metabolism forces cellular-signaling by accumulative reactive oxygen species in the mitochondria via the electron transport chain which promotes cellular-apoptosis or survival against various stresses. Pro homeostasis is imperative for vigorously apportioning cells, as it assists in preserving viable growth under long‐term stress. Pro also encourages stress-defending proteins through the expression of salt stress reactive genes owning to Pro-reactive elements in their promoters. Several studies have attributed that exogenous application of Pro enhances the activity of antioxidative enzymes, which lead to alleviating the adverse effect of environmental stresses. The chapter gives a holistic account of Pro homeostasis, taking into account the regulation of Pro synthesis, its catabolism and intra‐ and intercellular transport, all of which are vital components of growth and development in wheat challenged by stress.
