Modification of Flower Color Pigments and Color Composition with Hormonal Treatments and Sucrose in <i>Tulipa gesneriana</i> ‘Kingsblood’

Abstract

Three separate experiments were conducted to investigate the interplay between three phytohormones and sucrose for the change of flower color composition and the plant secondary metabolites in <em>Tulipa</em>. The variations of the physiological and morphological characteristics, with ABA at 5 and 10 mg/L (as experiment one), GA₃ at 300 ‎and 500 mg/L ‏‎‎(as experiment two), 50 and 100 µM of JA (as experiment three) and their interactions with sucrose at 1 and 2 g/L were analyzed. By reviewing the HPLC charts and UV-Vis spectra, it was found that the production of plant secondary metabolites, total flavonoids, and anthocyanins composition pigments was influenced by the foliar application of the plant hormones. The sucrose alone had no significant effect on the quantification of different phytochemicals, but the interaction with JA and ABA showed a considerable variation in the anthocyanin accumulation and total flavonoids. Both JA and ABA hormones, in spite of enhanced anthocyanin accumulation and increased cyanidin and pelargonidin pigment percentage, were associated with reduced vegetative growth parameters as well as vase life, compared to the control plants. However, GA₃ at 500 mg/L without sucrose played a key role in the accumulation of anthocyanin, postharvest performance, and the increase in the three major anthocyanin pigments. Moreover, the data provided evidence of interference between the sucrose and GA₃ in the regulation of the anthocyanin accumulation.