Study of excited gamma ray effects on the factors of the root function at the primary stage of growth of various species of Iranian wheat

Wheat seeds of 5 Iranian varieties were irradiated with acute gamma rays for total dose of 0-900 rad, at 50 rad/minute. 1 hour after irradiation they were sown in petri-dishes lined with filter paper and were kept under uniform conditions. 72 hours after irradiation the weight and length of the shoots and the embryonical roots were measured. Because of a better judgment of the roots efficiency the ratios ''rootweight to shootweight'' and ''rootlength to shootlength'' were calculated. The experiment was repeated simultaneously 10 times. In comparison with the control plants the 700 rad treatment has shown on an average of both ratios and all varities the most stimulation effects (33% increase) and the variety ''Azar'' has shown on an average of all treatments the greatest response (48% increase). These increases could have a high practical value, for a higher ratio signifies a better nourishment of the plants especially in the early stage of growth. (author)