Influence of paclobutrazol and cycocel sprays on the growth, flowering and chemical composition of potted Chrysanthemum frutescens plant

A pot experimental study was carried out during the two successive seasons of 2013 and 2014 to study the effect of paclobutrazol at 0.0, 20, 40 and 60 ppm and cycocel at 0.0, 1000, 2000 and 3000 ppm on growth, flowering and chemical composition of potted Chrysanthemum frutescens plant. Uniform terminal cuttings were planted in 8 cm plastic pots containing 1:1 mixture of peat moss and sand. On March 1^st  2013 and 2014, uniform well rooted cuttings were repotted in 20 cm diameter plastic pots filled with a mixture of 1 clay: 1 sand :1 peat moss (v:v:v). After one month from the repotting process, plants received four sprays of paclobutrazol at 20, 40 and 60 ppm and cycocel at 1000, 2000 and 3000 ppm plus tap water as control at two weeks intervals. The obtained results cleared that all paclobutrazol and cycocel concentrations decreased plant height, particularly paclobutrazol at 60 ppm in both seasons. Meanwhile, all applied treatments of paclobutrazol and cycocel statistically increased branches number / plant to reach its maximum with the highest concentration for each. The heaviest fresh and dry weights of leaves/plant were gained by 3000 ppm cycocel-sprayed plants in the two seasons. Also, paclobutrazol and cycocel treatments delayed the flowering of Chrysanthemum frutescens plant when compared with control plants which induced the earliest flowering in both seasons. The highest number of flowers/ plant was scored by 60 ppm paclobutrazol -sprayed plants. Whereas, the heaviest flowers fresh and dry weights/plant were scored by 3000 ppm cycocel-sprayed plants in the two seasons. Moreover, the highest show value (plant width/ height ratio) was recorded with paclobutrazol and cycocel at the highest concentration in the two seasons. The highest number of roots/plant was scored by 60 ppm paclobutrazol-sprayed plants, while the heaviest fresh and dry weights were registered by 3000 ppm cycocel-sprayed plants in both seasons. Furthermore, paclobutrazol and cycocel treatments statistically increased leaf NPK, total carbohydrates and total chlorophylls contents, being superior in the highest concentrations as compared with un-sprayed plants in the two seasons. All paclobutrazol and cycocel treatments increased leaf total phenols content (mg/ 100g F.W) but they still reduced total indoles (mg/100g F.W) of Chrysanthemum frutescens leaves.