Abscisic acid (ABA ) regulates a number of different processes , including ripening and seed dormancy , root growth , leaf senescence , and the phase transition from vegetative to generative growth . ABA is the main hormone stress enabling the plant to adapt to environmental factors such as drought, cold or salinity , which mediates the regulation of stomatal thereby controlling water flow and affecting the expression of genes related to stress .

Plant hormones are important in all aspects of plant growth and development , but the phenomenon of hormonal homeostasis is not fully understood. Conjugation of phytohormones is considered an important element of the mechanism responsible for the levels of these compounds in the cell. It is a process that occurs in all tested plants in response to environmental and physiological factors .