INFLUENCE OF POTASSIUM, SUGAR ALCOHOL, AND BORON ON GROWTH AND CHEMICAL COMPOSITION OF MELONS UNDER PROTECTED CULTIVATION

An experiment was conducted in Polytunnel house at Longitude 43.30, latitude 33.410 the Department of Horticulture, College of Agriculture, University of Anbar, during the spring season of 2023. The experiment was designed to investigate the effects of spraying with potassium, a combination of alcohol sugar (sorbitol), and boron on the vegetative traits and chemical content of melon leaves under protected cultivation conditions. The study included two factors: the first factor was spraying with potassium at three concentrations: 0, 4, and 8 gm L-1, and it was coded as K0, K1, and K2, respectively. The second factor was spraying with a combination of sorbitol and boron at five concentrations: the first treatment was the comparison (0 boron and 0 sorbitol), the second (20 milligrams liter-1 boron + 25 grams liter-1 sorbitol), the third (20 milligrams/liter boron + 50 grams liter-1 sorbitol), the fourth (40 milligrams liter-1 boron + 25 grams liter-1 sorbitol), and the fifth (40 milligrams liter-1 boron + 50 grams liter-1 sorbitol To obtain the best growth and yield from it ), and it was coded  where to T0, T1, T3, , and T4, respectively. Potassium was sprayed when 50% of the flowers appeared and until the fruit ripened at a rate of one spray per week. As for the combination of boron and sorbitol, it was sprayed after the appearance of 6-8 true leaves at a rate of three sprays between sprays every two weeks. The experiment was conducted as a factorial experiment within a complete randomized block design with three replicates. The study showed that the second potassium concentration (K1) achieved the highest vegetative growth traits (plant height, leaf area, number of nodes, and dry weight of the total vegetation, which were 311.98 cm, 95.05 dam2, 33.71 nodes plant-1, and 138.8 g plant-1,) compared to the lowest values achieved by K0 comparison plants, which were 297.34 cm, 82.64 cm2, 30.04 nodes plant-1, and 118.4 g plant-1, respectively. The combination of boron and sorbitol had a significant effect on vegetative growth traits, as treatment T4 significantly outperformed and achieved the highest plant height, leaf area, number of nodes, and dry weight of the total vegetation, which were 317.91 cm, 99.12 dam2 plant, 35.032 nodes -plant-1, and 146.7 g plant-1, respectively, compared to the lowest values for vegetative growth traits, which were given by the plants of treatment T0, which were 285.32 cm, 76.95 cm2, 28.60 nodes plant-1, and 107.6 g plant-1, respectively.