The interaction of salinity and chromium in the influence of barley growth and oxidative stress

The effect of chromium and NaCl on growth and anti-oxidative enzymes in two barley genotypes differing in salt tolerance was investigated in a hydroponic experiment. Salinity stress reduced plant growth, photosynthetic rate and stomatal conductance, while increased SOD and POD activities, and MDA content in barley plants. CM72, a salt-tolerant genotype was less affected by salinity stress than Gairdner, a salt-sensitive genotype. The effect of Cr on plant growth and anti-oxidative enzymes varied with Cr level. Under low Cr level (10 mu mol), plant growth inhibition and oxidative stress caused by salinity stress were generally alleviated, in particular for Garidner. The combined stress of high Cr level (50 mu mol) and NaCl stress caused more severe oxidative stress, resulting in further reduction of plant growth parameters, photosynthetic rate and stomatal conductance as compared to two stresses alone.