Improving quality indices of Rosa ‘Yellow Finesse’ using methyl jasmonate and benzyl adenine

Plant growth regulators (PGRs) play a key role in regulating physiological and morphological development of plant species. Application of these PGRs can improve preand post-harvest quality and quantity of ornamental flowers and lessen the harmful effects of injury incurred at harvesting time. The objective of this study was to determine the appropriate spraying solution for improving preand postharvest quality indices of Rosa hybrida L. cv. ‘Yellow Finesse’. So, the effect of methyl jasmonate (MeJA) at 0, 50, 100, or 150 mg*l alone or in combination with benzyl adenine (BA) at 0, 10, or 20 mg*l was investigated. Plants were sprayed at a 15-day interval for two months and then harvested at a mature bud stage. The results showed that flower head diameter and leaf chlorophyll content were improved by applying 100 mg*l MeJA + 20 mg*l BA. The application of 100 mg*l MeJA + 10 mg*l BA or 10 mg*l BA resulted in improving its petal carotenoid content. The plants treated with 150 mg*l MeJA had the longest shelf life. The findings demonstrated that while 100 mg*l MeJA + 20 mg*l BA and 100 mg*l MeJA + 10 mg*l BA were the best preharvest spraying solutions due to the highest carotenoid content and largest flower head diameter. Particularly, 150 mg*l MeJA was the best spraying solution for extending cut flower shelf life and had the potential to function as a postharvest treatment.