Phytohormones

Abstract

During evolution in plants, a sophisticated system of receptors and signaling pathways has emerged that allows for appropriate responses and responses to these signals. One of such signals is the plant hormone – phytohormone. Abscisic acid is a sesquiterpene, which has important roles in seed development and maturation, in the synthesis of proteins and compatible osmolytes, which enable plants to tolerate stresses due to environmental or biotic factors, and as a general inhibitor of growth and metabolic activities. Abscisic acid is essential for the initiation and maintenance of tuber dormancy. Its main antagonist is gibberellic acid, which affects carbohydrate metabolism, indicating the budding of tubers. Gibberellic acid is a naturally occurring plant hormone that is used as a plant growth regulator to stimulate both cell division and elongation that affects leaves and stems. Salicylic acid belongs to a group of plant phenols that play an important role in the regulation of plant growth, development, and interaction with other organisms. Salicylic acid (SA), a phytohormone, is a promising compound that can reduce the sensitivity of plants to environmental stresses through regulation of the antioxidant defense system, transpiration rates, stomatal movement, and photosynthetic rate. Phytohormones are essential regulators of plants in two physiological processes that coordinate growth, reproduction, and stress resistance. These molecules also show biological activities on human cells and animal models.