DIFFERENTIATION OF CHLORIDE AND SULFATE SALINITY ON THE BASIS OF IONIC DISTRIBUTION IN GENETICALLY DIVERSE CULTIVARS OF WHEAT

Sulphate (SO4) salinity, in general, was found to be more injurious th an chloride (Cl) salinity in all the four genetically diverse wheat cu ltivars - Triticum monococcum (C1), T. aestivum cv. chinese spring (C2 ), T. turgidum cv. langdon (C3) and amphidiploid (C4) obtained by a cr oss between T. aestivum cir. chinese spring x Thinopyrum bessarabicum grown in hydroponic cultures containing iso-osmotic saline treatments T1 (90 mM NaCl), T2 (45 mM NaCl+22.5 mM Na2SO4), T3 (15 mM NaCl + 37.5 mM Na2SO4), and T4 (45 mM Na2SO4). Among the cultivars, C4 followed b y C2 and C3 appeared to be more salt resistant and C1 the most salt se nsitive as far as various observations on osmotic potential and intern al ion accumulation were concerned. Salt resistance could be ascribed to more exclusion of Na and C1 ions. Sulphate injury might be due to l ess effective sequestration or mobility of this ion towards some innoc uous centres of plant tissues. Most of the interactive effects of cult ivar versus salinity were prominently higher in cultivar C4 in treatme nt T1.