Approaches to Increasing Salt Tolerance in Crop Plants

Abstract

Soil salinity is widely recognized as a major threat to global food security. Salinity and other abiotic stresses, which are expected to be more frequent in future due to disturbances in global climate, pose a serious challenge for plant scientists to ensure food supply for the growing world population. Several approaches have been advocated to address the salinity problem, but the most logical solution to maintain crop productivity in salt-affected areas is to enhance salt tolerance of crop plants. Due to the genetic and physiological complexity associated with salt tolerance, efforts to breed salt-tolerant plants have met with limited success. Although progress has been made in deciphering the genetic basis of salt tolerance, sustained efforts are needed to systematically dissect and utilize the natural variability in the available germplasm for improving crop adaptation in saline environments using modern genomics tools. Wide range of variability for salt tolerance in wild relatives, cultivars of major field crops, and halophytes offers bright prospect for discovery of superior salt-tolerant alleles for crop improvement. With an enhanced understanding of molecular mechanisms and the associated genes for component traits of salt tolerance, it would be possible to breed salt-tolerant plants using an integrated approach involving conventional breeding, physiological analysis, marker-assisted selection, and transgenic technology.