Plant growth regulators modulate the growth, physiology, and flower quality in rose (Rosa hybirda)

Abstract This experiment was conducted to investigate the effect of different plant growth regulators as a foliar spray on greenhouse rose cv. Rosa hybirda to increase the growth and vase life. Main objective of this research is exogenous application of plant growth regulators that significantly increase the flower quality of rose. A total of 5 treatments T1 = control, T2 = Thiourea @ 60 mg/L, T3 = Ascorbic acid @ 60 mg/L, T4 = Salicylic acid @ 60 mg/L and T5 = Humic acid @ 60 mg/L were tested in complete randomized design with three replications. All the treatments improved the yield, flowering quality and vase life as compared to control treatment. Although, various treatments, salicylic acid showed the maximum plant height (123.5 cm) and days to first flower harvest (87 days). Results declared that foliar spray of plants growth regulators increased the chlorophyll a, chlorophyll b and total chlorophyll contents. Additionally, flowering parameters like flower stalk length (16.533 cm), fresh weight of flower (15.95 g), dry weight of flower (2.20 g), flower diameter (10.133 cm), number of flowers per plant (10.133), flower quality (4.6) and vase life (2.86 days) were significantly increased in plants sprayed with salicylic acid and humic acid @ 60 mg/L.