Comparative Evaluation of Phytohormonal Responses in Plants Under Different Abiotic Stress Conditions

Abstract

Abiotic stresses such as drought, salinity, extreme temperatures, and heavy metal toxicity significantly affect plant growth, development, and yield. To adapt and survive under such adverse conditions, plants rely on intricate hormonal signaling networks that regulate physiological and molecular responses. This study presents a comparative evaluation of key phytohormones—including abscisic acid (ABA), ethylene (ET), salicylic acid (SA), jasmonic acid (JA), auxins, cytokinins (CK), gibberellins (GAs), and brassinosteroids (BRs)—and their diverse roles in modulating plant responses to different abiotic stresses. While ABA serves as a primary signal under drought and salt stress, hormones like JA and SA are more active in stress-related defense and detoxification mechanisms. The interaction and cross-talk among these hormones enable plants to fine-tune their responses, depending on the nature and severity of the stress. This review synthesizes recent findings from molecular and physiological studies that highlight hormone-specific response patterns and adaptive mechanisms. It also discusses how stress-specific hormonal pathways interact to influence gene expression, osmotic balance, and reactive oxygen species (ROS) management. By comparing these divergent hormonal strategies, the study offers valuable insights into potential biotechnological and agronomic approaches to enhance stress tolerance in crops, contributing to sustainable agriculture in the face of climate change.