Differences in Behavior of Salt Tolerant and Salt and Water Deficiency Tolerant Wheat Genotypes When Subjected to Various Salinity Levels

Genetically diverse wheat genotypes comprising salt tolerant (V1 and V2), salt and water deficiency tolerant (V3, V4 and V5) and salt sensitive (V6) were subjected to various salinity levels. The objective was to see whether ion selectivity amenable to ion regulation and ion discrimination exist simultaneously in one genotype and how do they interact when subjected to various salinity levels. Plants were grown under salinity till the emergence of flag leaf. Analysis for Cl−, Na+, K+ and of K+/Na+ ratio indicated higher concentration of K+ compared to Na+ and Cl− in water deficiency tolerant group suggesting reduced uptake of both ions. In V1 and V2, concentration of Na+ and Cl− were also low. Discrimination for K+-Na+ in V2, V3 and V4 was manyfolds higher than the parent V1 possibly due to differential transfer to this material, of various alleles native to Ae. cylindrica. V6 lacked ion selectivity capable of efficient K+-Na+ discrimination. Hence both K+ concentration and K+/Na+ ratio were the lowest making V6 a salt sensitive cultivar. The study revealed difference in type and level of salt tolerance in various genotypes, which indicated new ways of enhancing salt tolerance in commercial wheat varieties.