The effect of cycocel consumption method on the growth and flowering of azalea ‎‎(Rhododendron simsii cv. Japonica Red)‎

Document Type : Full Paper


1 M. Sc. Student, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran

2 Professor, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran


In order to investigate the effect of cycocel consumption on some morphological and physiological traits of azalea cultivar Japonica red, two separate experiments as a completely randomized design with five treatments and three replications were conducted. For this purpose, cycocel with two methods of foliar spraying of plants with concentrations of zero (control), 1000, 2000, 3000 and 4000 mg / l and soaking the root area with concentrations of zero (control), 750, 1500, 2000 and 2500 mg / l was used. The results showed that by foliar application, at a concentration of 4000 mg / l cycocel, the highest number of flowers (21.33), number of branches (13.4), total chlorophyll (34 μg/g FW) and anthocyanin (16.29 mg /g FW) was observed. In root soaking method, application of 2500 mg /l of cycocel increases the number of flowers (16.66), number of branches (8.7), total chlorophyll (49 μg/g FW) and anthocyanin (16.12 mg /g FW). The maximum time of flower opening of azalea was achieved in foliar application at 1000 mg /l cycocel in 182 days, while in the root soaking method at 2500 mg / l cycocel occurred in 210 days. Overall, in the foliar application method with a concentration of 4000 mg/l cycocel in comparison to the root soaking method, the optimal dwarfism index is more suitable to increase the marketability of azalea.


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