Various processes can boost growth traits and the nutritional value of fruits. One such technique is the application of chelating substances for enhancing crop growth and productivity. The following study aimed to determine the effect of humic acid and chelated iron on the growth and nutritional content of apple (Malus domestica L.) cv. Sharabi, carried out in 2022 at the University of Kufa, Iraq, The experimental layout was in a randomized complete block design with three replications. The experiment included nine fertilizer combinations of the humic acid and chelated iron in different ratios. Results showed the fertilizer combination of humic acid (5 ml L^-1) + chelated iron (30 mg L^-1) was superior in the apple seedling height, number of branches, number of leaves, leaf area, dry weight of shoots, carbohydrate content, and nitrogen content, with an increased average values (39.33 cm, 7.84 branches seedling^-1, 295.07 leaves seedling^-1, 33.01 cm², 43.46 g, 8.81 mg g^-1, and 2.42%, respectively). The fertilizer combination of humic acid (5 ml L^-1) + chelated iron (0 mg L^-1) excelled in the fresh weight of shoots and the chlorophyll content (99.18 g and 36.10 mg g^-1, respectively). For phosphorus content, the combination of humic acid (2.5 ml L^-1) and chelated iron (15 mg L^-1) was leading with an average of 0.57%, while for potassium content, the combination of excelled humic acid (5 ml L^-1) and chelated iron (15 mg L^-1) showed the highest average (3.90%) in the apple cultivar Sharabi.

Keywords: Apple (M. domestica L.), humic acid, chelated iron, growth and yield traits, nutritional content

Key findings: In apple (M. domestica L.), the fertilizer combination of humic acid (5 ml L^-1) + chelated iron (30 mg L^-1) proved superior in most traits, such as seedling height, the number of branches and leaves, leaf area, dry weight of shoots, and carbohydrate and nitrogen contents.