EFFECT OF FOLIAR APPLICATION WITH FORCHLORFENURON AND GIBBERELLIC ACID IN VEGETATIVE GROWTH AND CHEMICAL CONTENT OF WASHINGTON NAVEL ORANGE TRANSPLANTS

Abstract

This study was conducted in the lath house of Horticulture and Landscape Gardening Department, College of Agriculture , University of Anbar for the period from April to December 2021, to study the effect of foliar spraying with growth regulators of Forchlorfenuron and Gibberellic acid in the vegetative growth and chemical content in two years old of Washington navel orange transplants and budded on rough lemon rootstock, the experiment included the foliar application with forchlorfenuron at four concentrations: 0, 4, 8 and 12 mg L-1 which symbolized of F0, F1, F2 and F3 respectively as well as spraying with three levels of GA3: 0, 25 and 50 mg L-1 which symbolized of G0, G1 and G2 respectively. A factorial experiment was conducted with Randomized Complete Block Design (RCBD) with three replicates for each treatment, the results can be summarized as follows: the two factors of study affected significantly in all of the studied traits especially the foliar application treatment of forchlorfenuron at F2 concentration and the spraying with GA3 at a concentration of G2 where achieved the highest significant increase in the secondary shoots' number, number of leaves increment, leaves area, dry weight of vegetative parts, shoots content of total carbohydrates, concentration of nitrogen and total chlorophyll content in leaves which gave values reached to 5.94, 4.79 shoot sapling-1 and 95.83, 80.62 leaf sapling-1, 34.12, 30.68 dm2 and 87.62, 74.79 g and 9.12, 9.00% and 2.51, 2.50% and 1.44, 1.40 mg.g-1 fresh weight respectively for both study factors, while the control treatment recorded the lowest values for these traits.