"There are numerous challenges facing agriculture to meet the increasing demand for sustainable alimentary production and ensure that the rapidly growing population has high-quality nutrition. In order to ensure sufficient food production, the yield per arable land area must be increased. The application of growth regulators to modulate plant growth was a method for achieving this aim. Plant growth regulators (PGRs) are substances in complex formulations that are capable of supporting, inhibiting, or modifying physiological features, production, and/or stress reactions when used on plants or seeds. PGRs have been gradually increasing in conventional agriculture in the last 20 years as growers have recognized their advantages. Unfortunately, growth in the market for PGR can be constrained by a lack of innovation in the context of constant innovation and the discovery of innovative, affordable, customary, and efficient PGRs, which will require an increasing demand for new products. Abiotic and biotic stresses adversely affect plant growth and productivity. Phytohormones regulate key physiological events under normal and stressful conditions for plant development. Phytohormones are chemical messengers that regulate the normal development of plants and their responses to environmental stimuli. The biosynthesis of phytohormones by plants provides them with a mechanism for adapting to changing conditions. Previous research efforts have discovered the important roles of phytohormones and their interactions in the regulation of plant adaptation to various stresses. Molecular studies have revealed numerous plant hormonal pathways; each of which consists of several signaling components that relate a particular hormone perception to its regulation. The signal transduction pathways of auxin, abscisic acid, cytokinin, gibberellins, and ethylene have been thoroughly investigated. Brassinosteroids, jasmonates, salicylic acid, tocotrienol, melatonin, phenolic compounds, and strigolactones have lately emerged as promising signaling routes for understanding their multiple roles in plant physiological processes"--