تاثير كاربرد اسيد جيبرليك بر خصوصيات رشد رويشي دانهال هاي كنار(Ziziphus spina-christi)

The Effect of Gibberellic Acid on Vegetative Characteristics of Ber tree (Ziziphus spina-christi) Seedlings

Application of gibberellic acid (GA3) increases the rate of vegetative growth of plants. This research was conducted to study the effect of gibberllic acid (0, 250, 500 and 750 mg r1) on annual seedling growth of Ber tree. The experiment was carried out in randomized complete block design (RCBD) with four replications. Measured parameters included: length of internodes, height of shoot, fresh and dry weight of leaf, shoot and root, leaf area and root area. The result showed that 750 mg I"1 GA3 was the most effective on the length of internodes and height of shoot and its difference with the other treatments were significantly at 1% probability. The other vegetative parameters included: leaf area, fresh weight, dry weight of leaf and shoot of seedling in high concentrations (500, 750 mg 1"!) which were significantly different at 5% probability compared with the control ones. The result of this study showed that spray of gibberllic acid did not have significant effect on the root area, fresh and dry weight.