Improving vegetative growth characteristics and mineral content in pomegranate trees c.v. "Wonderful".by spraying Brassinolide, proline and boron

This study was conducted in the orchard of the Agricultural Research and Experiments Station, College of Agriculture, University of Kirkuk, during the 2024 growing season to investigate the effect of foliar spraying with the growth regulator Brassinolide at three concentrations (0, 2, 4 mg L⁻¹), the amino acid proline at three concentrations (0, 100, 200 mg L⁻¹), and boron at two concentrations (0, 30 mg L⁻¹), as well as their interactions, on some vegetative growth traits and mineral content of pomegranate trees, cultivar Wonderful. A randomized complete block design (RCBD) was used with three factors, four replications, and one tree per experimental unit. The results obtained can be summarized as follows:Foliar spraying with Brassinolide had a significant effect on vegetative growth traits and mineral content of pomegranate trees, with 2 mg L⁻¹ affecting (shoot length and shoot diameter) reaching )37.61 cm, 3.32 mm(, and 4 mg L⁻¹ affecting (leaf area, total chlorophyll, and the percentages of nitrogen, phosphorus, and potassium in the leaves) reaching) 7.34 cm , 25.29 mg/100g fresh weight (%2.20, % 0.144 , % 2.72 , respectively . Foliar spraying with the amino acid proline at 200 mg L⁻¹ led to a clear significant increase in all studied vegetative growth traits (shoot length, shoot diameter, leaf area, total chlorophyll) reaching ) 38.32 cm, 3.36 mm , 7.54 cm² , 24.72 mg/100g fresh weight) respectively and two mineral content traits (percentage of nitrogen and potassium in the leaves) reaching. Foliar spraying with boron at 30 mg L⁻¹ resulted in significant increases in vegetative growth traits and mineral content (shoot length, leaf area, total chlorophyll, and the percentages of nitrogen and potassium in the leaves) reaching respectively. A clear significant effect of the two-way and three-way interactions among the study treatments was observed in most of the studied traits.