EFFECT OF SALINITY AND HEXAVALENT CHROMIUM STRESSES ON UPTAKE AND ACCUMULATION OF MINERAL ELEMENTS IN BARLEY GENOTYPES DIFFERING IN SALT TOLERANCE

The effect of hexavalent chromium (Cr) and sodium chloride (NaCl) stresses on the uptake and accumulation of mineral nutrients in two barley (Hordeum vulgare L.) genotypes differing in salt tolerance was investigated in this study. Sodium chloride stress decreased potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), zinc (Zn), manganese (Mn) and copper (Cu) concentration and accumulation in barley plants, and there was less of a decrease in salt-tolerant 'CM72', than in 'Gairdner', a salt-sensitive genotype. The effect of Cr on mineral concentration and accumulation varied with Cr level. At a high Cr level (50 mu M), concentration and accumulation of all mineral elements were significantly reduced. But at a low Cr level (10 mu M), nutrient concentration and accumulation were increased. Moreover, low Cr level alleviated the inhibiting effect of NaCl stress on nutrient uptake and accumulation. The combined stress of high Cr level and NaCl stress, on the whole caused further reduction of the mineral concentration and accumulation as compared to two stresses alone.