Effect of Foliar Application of Paclobutrazol and Cycocel on Vegetative Growth, Flowering and Chemical Constituents of Zinnia elegans Plants

Abstract

The present study was carried-out at Antoniadis Research Branch, Horticulture Research Institute, A.R.C. Alexandria, Egypt during the two successive seasons of 2020 and 2021. This study, aimed to test the effect of applying foliar sprays of cycocel and paclobutrazol in improving the quality and performance of Zinnia elegans plants. The Zinnia seedlings were planted individually in plastic pots 25 cm diameter of sandy soil. The plants were sprayed with cycocel at the concentrations of 500, 1000, 1500 and 2000mg/l and paclobutrazol at the concentrations of 100, 200, 300 and 400 mg/l. The obtained results showed that spraying with cycocel at 2000 mg/l and paclobutrazol at 400 mg/l significantly increased decreased plant height, number of leaves per plant, leaves dry weight, leaf area, number of branches per plant, stem diameter, stem dry weight and root dry weight. In addition to, the obtained results showed that spraying with cycocel at 2000 mg/l and paclobutrazol at 400 mg/l significantly increased number of flower per plant, flower diameter, flower fresh weight, flower dry weight and flower vase life. As such as, The obtained results showed that spraying with cycocel at 2000 mg/l and paclobutrazol at 400 mg/l resulted in the highest chlorophyll content, carbohydrates content , nitrogen percentage in the leaves, phosphorus percentage in the leaves and potassium percentage in the leaves, Therefore, this study to investigate the effect of different of cycocel and paclobutrazol treatments, on the vegetative growth and flower growth and chemical constituents of Zinnia elegans plants grown sandy soil.