Gibberellic Acid (ga3 And Npk Nano-fertilizers Can Enhance The Growth And Development of Buxus Sempervirens ‘suffruticosa’ Plant

Abstract

This study was conducted in the greenhouse of the College of Agricultural Engineering Sciences, University of Duhok for the period between 15 th March 2022 to 15 th March 2023. The study aimed to test the effect of Gibberellic acid (GA3) with three concentrations (0, 200, 400) mg L -1 , and (1, 2, 4) g L -1 of NPK Nano fertilizers sprayed two times on the growth and development of Buxus sempervirens 'Suffruticosa' plant and the experimental units were organized by using (RCBD) Randomized Complete Block Design, with two factors 3×3= 9 treatments and three replications then taking three plants for each replication. The results showed that the 400 mg L -1 of GA3 significantly increased the number of branches, plant weight, number of leaves, growth index and leaf area compared with 200 mg L -1 which resulted in increasing plant height, vegetative dry weight, root dry weight, total chlorophyll content compared with control. Increasing of Nano fertilizer concentration up to 4 g L -1 significantly increased the plant height, number of branches, plant weight, number of leaves, vegetative dry weight, root dry weight also leaf area compared with 2 g L -1 which affected on increasing total chlorophyll content. The highest branches number (17.33) branch/plant, highest plant weight (189.20) g, number of leaves (143.33) leaf/plant, vegetative dry weight (42.30) g leaf area (2755.00) cm 2 was obtained from the interaction of (4 g L -1 + 400 mg L -1 ) of NPK Nano fertilizer and GA3 while plant height gave the same result (58.67) at both concentration (4 g L -1 + 200 mg L -1 ) and (4 g L -1 + 400 mg L -1 ), but in other side maximum total chlorophyll and growth index were from interaction of (2 g L -1 + 200 mg L -1 ) and gave (87.97) , (74279) respectively. Overall, the interaction between (gibberellin at 400 mg L -1 + Nano-NPK fertilizer 4 g L -1 ) provided best results of most studied characteristics. Also, both factors individually provided best results when 400 mg L -1 gibberellin and 4 g L -1 Nano-NPK fertilizer were used.