Response of Olive Saplings cv. Khistawi to Soil Application with Humic Acid and Foliar Spray with Urea

Abstract

The experiment was conducted in the lath house belonging to the Department of Horticulture and Landscape Gardening- College of Agriculture - Anbar University, for the period from the beginning of March 2022 to mid of November 2022, to study the effect of soil application with humic acid at three levels (0, 10, 15, g sapling−1) denoted by H0, H1, H2 respectively, and foliar spray with urea at three concentrations (0, 10, 15 g L−1) denoted by N0, N1, N2 respectively, and the interaction between them in the vegetative growth traits and leaf mineral content of olive saplings cv.khistawi. The results showed a positive effect when adding humic at concentration 15 g.sapling−1 which showed a. Adding 15 g seedling−1 significant superiority in the rate of sapling height increment, increment of number main branches stem branches, leaf area, and the percentage of nitrogen, phosphorus, and potassium in the leaves, reaching 23.367 cm, 17.275 branch.sapling−1, 5.190 cm2, 1.824%, 0.454%, 1.813%, respectively, compared to the control treatment. Foliar spraying with urea (15 g L−1) also resulted in a significant improvement in the aforementioned traits when adding humic acid, reaching 24.259 cm, 17.616 branch.sapling−1, 5.607 cm2, 1.844%, 0.466%, 1.802% respectively, compared to the control treatment. The interaction between the studied factors showed a similar behavior to the individual factors for all studied traits.