Response of Freesia (Freesia hybrida) to spraying with an organic acid (Laq-Humus) and chelated iron and their effect on growth and flowering indicators

Abstract

An experiment was conducted in the nursery of the college of Agriculture, University of Kufa during the agricultural season (2017-2018) in a house covered with green saran to study the effect of spraying organic acid (Lag-Humus) and chelated iron (Fe 6%, EDTA) on the growth and flowering indicators for freesia. The experiment was conducted according to The Randomized Complete Block Design (RCBD), with three replicates and two factors. The first factor is spraying three concentrations of organic acid, which are (3, 0 and 6 ml.L-1) and the second factor is spraying three concentrations of chelated iron are (0, 20 and 40 ml.L-1). The averages were compared according to the Least Significant Difference Test (L.S.D) and at a probability level of 0.05. The results also showed that spraying organic acid at a concentration of (6 ml.L-1) with chelated iron at a concentration of (40 mg.L-1) significantly increased the dry weight of the total vegetative, the leaves content of total chlorophyll, floret diameter, the length of the flower inflorescence, vase life and the leaves content of iron which amounted to (1.75 g, 49.78 mg.100 g-1, 6.13 cm, 9.00 days and 47.50 mg.kg-1), respectively compared to the plants of control treatment, which gave the lowest values amounted to (1.01 g, 44.46 mg. 100 g-1, 3.23 cm, 6.33 days and 36.82 mg.kg-1). while spraying the organic acid at a concentration of (6 ml.L-1) with chelated iron at a concentration of (20 mg.L-1) significantly increased the number of leaves per plant, the leaves content of the total soluble Carbohydrate, the number of flower inflorescences per plant, the number of florets per flower, and the percentage of nitrogen and reduced the number days required to open the first floret which amounted to (8.33 leaves and 6.34 mg.kg-1 dry weight, 5.66 inflorescences, 12.33 florets, 2.03% 128.33 days), respectively compared to the control treatment, which gave the lowest values amounted to (3.00 leaves, 4.20 mg.kg-1 dry weight, 2.33 inflorescences, 6.00 florets, 0.62%), respectively and the highest average in the number of days required to open the first floret amounted to (138.00 days).