Interaction effect of hormones (auxin and gibberellin) and fruit pruning on the growth and yield of two bell pepper cultivars

Capsicum has great value and importance among vegetables. Many factors such as pruning and hormones affect its performance. This research includes pruning and hormone treatments on yellow cultivar (Lumos) and red cultivar (Lorka). This study was performed in two experiments. The first test of the main and reciprocal effects of cultivar, pruning and hormone on morphological traits was performed on two yellow and red pepper cultivars. This test was performed with 4 pruning treatments: No pruning, 10%, 20% and 30% pruning. The test was continued by other 9 hormone treatments including control, gibberellin with different concentrations as1×10-5 and 2×10-5, Auxin with different concentration as 1×10-5 and 2×10-5. According to their interactions the test was performed by using a split pallet in four applications. Based on the results of the first experiment, the second experiment is the main and opposite effects of pruning and hormone on Biochemical traits cultivar of yellow cultivar with three pruning treatments: no pruning, 10% pruning, 30%pruning and 5 hormone treatments including control, GA1, Aux1, GA1-Aux1 and GA1-Aux2 were performed as a factorial experiment with three random replications. The research results illustrate that fruit thickness, fruit coloring time, ripening time and indicators L and b were higher in yellow cultivar. Characteristics such as fruit weight, fruit length, fruit diameter, color indicators, rapid coloring and ripening with 10% pruning and 20% pruning were the best. GA hormone with Aux improves fruit thickness, minimum seed weight, fastest coloring, ripening, TSS, color indicators L, b and hardness in different parts. In the main effects, the highest yield was obtained in yellow cultivar, pruning 20% and Aux1. In contrast, pruning and hormone had the highest yield in yellow cultivar, 30% of Aux1 and in red cultivar, 20% of Aux2-GA1. Based on the results of the first experiment, yellow cultivar was selected as the best cultivar for fruit. The highest amount of carotenoids was observed in pruning 10% of Aux2-GA1 and the highest amount of vitamin C were in pruning 30% of GA1-Aux1. The highest acidity of fruit was related to pruning 30% and the highest antioxidant was in GA1with pruning 30%. In conclusion the best results were for yellow cultivar, pruning 10% and 20%, simultaneous and simultaneous hormonal treatments (in yellow cultivar: GA1-Aux1 and GA1-Aux2; in red cultivars: GA2-Aux1 and GA2-Aux2).