Effect of Foliar Spraying with Putrescine and Indole Acetic Acid on Growth and Flowering of Two Strains of Snapdragon Plant cv. ‘Opus III/IV’

Abstract

During the autumn of 2022 and 2021, the experiment was carried out in a plastic greenhouse at the Baqubah center nursery, which is part of the Diyala Agriculture Directorate to check out what happens when you sprinkle foliar fertilizer with putrescine at concentrations 0, 50, 100 and 150 mg L-1, symbolized by P0, P50, P100 and P150 mg L-1, respectively, and Indole acetic acid at concentrations 0, 50, 100 and 150 mg L-1, symbolized by IAA0, IAA50, IAA100 and IAA150 mg L-1, respectively, on growth and flowering of two strains (white and red) of snapdragon plant (Antirrhinum majus L.) cv. ‘Opus III/IV’After being sprayed with putrescine through the leaves, Major enhancements were seen in nearly all aspects of the plant’s growth, both vegetative and floral. Plant height (111.49 cm), number of leaves (433.37 leaves plant-1), and flower stalk length (86.33 cm) were all significantly improved by foliar spraying treatment at a concentration of 150 mg L-1, while leaf area (4723.0 cm2) was significantly improved by spraying at a concentration of 100 mg L-1, and best results were achieved by spraying at a concentration of 50 mg L-1 (102.42 days). Foliar spraying with Indole acetic acid led to a significant increase in vegetative and flowering growth traits. Foliar spraying treatment at a concentration of 150 mg L-1 resulted in a significant increase in the traits represented by percentage of total carbohydrates (18.37%), nitrogen (2.93%), phosphorous (0.58%) and potassium (3.00%) in the leaves, number of inflorescences (10.75 inflorescence plant-1), while spraying treatment with concentration of 50 mg L-1 excelled and gave the best results for the vase life (9.55 days). It is clear from the results that the two strains varied in the traits of vegetative and flowering growth, where they varied in the strength showing of the traits, as the white strain excelled in most of the vegetative and flowering traits and showed a significant increase in number of leaves (421.90 leaf plant-1), leaf area (4516.56 cm2), flower stalk length (84.10 cm), and the vase life (10.11 days), while the red strain showed a significant effect in percentage of total carbohydrates (13.09%), nitrogen (2.21%), phosphorous (0.42%), potassium (2.32%) in the leaves, and number of inflorescences (9.33 inflorescence plant-1). All vegetative and floral growth parameters were significantly affected by the interaction between putrescine and Indole acetic acid in foliar spraying for two snapdragon plant strains. The best results were found in the red strain’s interaction treatment with spraying of Indole acetic acid at a concentration of 150 mg L-1 for total carbohydrate content (20.70%), nitrogen (3.18%), phosphorus (0.70%), and potassium (3.25%) in the leaves, as well as the number of inflorescences per plant (10.75 inflorescences plant-1). The white strain’s interaction treatment with spraying of putrescine at a concentration of 50 mg L-1 (102.42 days).