Plant Growth Regulators and Salt Stress: Mechanism of Tolerance Trade-Off

Abstract

With the advent of sophisticated technology and techniques in farming sectors, the problem of salt stress has increased manifold. Salt stress causes various alterations ranging from genetic to morphological level in crop plants. In order to improve salt stress tolerance, some sustainable strategies should be chalked out which on one hand engineer tolerance to salt stress and on the other side enhance photosynthesis, growth, and yield of crop plants. Plants have developed numerous strategies of tolerance to overcome the menace of salt stress. Among various practices adopted, the signalling crosstalk of plant growth regulators (PGRs) has received special attention recently among plant physiologists. In the present chapter, an appraisal has been prepared to explore the tolerance trade-off mediated by PGRs, viz. salicylic acid (SA), nitric oxide (NO), brassinosteroids (BRs), abscisic acid (ABA), methyl jasmonate (MeJ), and melatonin (Mel), in plants under salt-challenged environments. The present chapter highlights the role of PGRs for engineering tolerance against salt stress in various crop plants. Furthermore, the underlying mechanisms by which plants perceive signals of stress, which trigger signal transduction cascades, have also been elaborated. Moreover, the role of tolerance trade-off under salinity stress by PGRs, namely, SA, NO, BRs, ABA, MeJ, and Mel, has also been dissected in detail.