Effect of Humic Acid on Tolerance indexes of Barley plant to Cadmium Toxicity

This study was carried out to evaluate the effect of different levels of Humic acid (0, 400, 800 ppm) on tolerance index of barley plant to different levels (0, 25, 50 and 100 ppm) of Cadmium. The experiment was designed according factorial completely randomized design with three replications. The results revealed that the combination effect of Humic acid and Cadmium significantly increased the total dry weight, number of spikes and dry weight of straw, as well as in total dry weight of plant, cadmium tolerance was found by treatments HA0CD50, HA0CD10, HA400CD0, HA400CD25, HA400CD100, HA800CD50, HA800CD100. Cadmium significantly decreased the relative chlorophyll production rate (RCPR) of Barley plant