The effect of decapitating on African marigold under foliar application of gibberellic acid

One of the characteristics of ornamental leaf plants is produce enough leaves and side branches to create a dense appearance. In some cases it is necessary to treatment non-causing varieties branch with some of the growth hormones to produce enough leaves and side shoots to achieve this goal. The most common treatment-causing agents are topping the branch and gibberellic acid that produce foliage in plant. This research was conducted in order to influence the topping and application of gibberellic acid on vegetative and reproductive growth of seasonal flowers African marigold. Topping stimulate lateral buds and produced more lateral branches. In this study topping as a first factor in three levels (0, 45 and 90 days before transplanting) and Gibberellic acid as the second factor in four levels (100, 200 and 300 mg / lit) were used in pot and in the open air under a factorial experiment with a completely randomized design (CRD) in 4 replicates in 4 pots. The seeds were planted in late summer. After six leaflets in (7 cm) seedlings were transferred to pots. Flowers in vases were deployed after (15 to 20 days after transplanting) were treated with gibberellic acid and topping. Spraying was carried out in three stages at intervals of 10 days. Distilled water was used to control plants. The results showed that the use of gibberellic acid combined with a topping treatment at 120 days after spraying increases the amount of chlorophyll index, plant height, length and lateral root volume. The number of open flower, bud and stem diameter had highest performance in the 120 days after spraying the treatment of100 mg/lit of gibberellic acid, respectively. Therefore topping combined with gibberellic acid at a concentration of 200 ppm gibberellic acid increases morphological growth, flowering and chlorophyll and carotenoid synthesis to accelerate significantly the African parsley.