Saeed Jafari - Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
Ali Nikbakht - Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
Maryam Haghighi - Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, Iran
Sara Shahin Varnousfaderani - Department of Horticulture, College of Agriculture, Isfahan University of Technology, Isfahan, Iran

Purpose: This research investigated the effect of different regimes of supplementary LED light on physiological and morphological traits of two cultivars of cut Roses. Research method: In this study, treatments included cultivars (Allstar and Dolcevita) and nine light regimes including (Control, LED night from ۵ pm to ۷ am, LED day from ۷ am to ۵ pm, LED night day (۲۴ hours light) and LED dark (۲۴ hours, without sunlight) which were all applied in two intensities of ۲۰۰۰ and ۴۰۰۰ lux. Findings: The results showed that the LED light regime had a positive effect on morphological traits such as the number of buds and mean harvest, length, diameter and fresh weight of flowers. LED day ۴۰۰۰ lux improved bud diameter and mean harvest by ۱۸% and ۱۱۲% respectively compared with control in Dolcevita cultivar. The light regime also caused a significant improvement in physiological characteristics so that in Allstar cultivar LED day ۴۰۰۰ lux, chlorophyll a, b, total, and carotenoid were increased by ۶۶%, ۶۰%, ۶۳%, and ۶۴% respectively compared with control. The vase life in Allstar cultivar by LED night day ۴۰۰۰ lux intensity and Dolcevita cultivar by LED day ۴۰۰۰ lux were ۴۴.۵% and ۱۳۳.۲% higher than the control treatment, respectively. Research limitations: There was no limitation. Originality/Value: The results showed that LED night day with ۴۰۰۰ lux intensity had the best results in vase life in Allstar cultivar and LED day supplementary light with ۴۰۰۰ lux intensity increased the quantity and quality characteristics of roses.

Led, Light intensity, Light quality, Supplementary light, Vase life