Leaves Of Cut Rose Flower Convert Exogenously Applied Glucose To Sucrose And Translocate It To Petals

Abstract

To understand the role that the leaves play in the translocation of soluble carbohydrates in cut rose flowers, we first evaluated the effect of leaf removal on flower quality and the sugar content in petals. Cut rose flowers with leaves had higher soluble sugar content in petals compared with cut flower without leaves. Next, we treated cut flowers with radioactive glucose to clarify translocation routes of exogenously applied sugar. There was no significant difference between the specific radioactivity of sucrose and glucose in leaves, but specific radioactivity of sucrose in petals was much higher than that of glucose. These results suggested that most of the exogenously applied glucose first moved to the leaves, where it was converted into sucrose and then the synthesised sucrose was translocated to the petals. Our results showed that the leaves of cut rose flowers play an important role in the metabolism and transportation of exogenously applied soluble carbohydrates toward the petals, thus contributing to sustaining the post-harvest quality.

Petal Growth Physiology of Cut Rose Flowers: Progress and Future Prospects

“…In Calendula arvensis, its flower opening and closing circadian rhythm followed the light-dark cycle in a manner dependent upon which flower had been exposed when the leaves were subjected to a different light-dark cycle from the flowers (van Doorn & van Meeteren 2003). In cut roses, rose petals can perceive red and blue light and synchronize their growth to photoperiods (Horibe & Yamada 2014a;Horibe & Yamada 2014b;Horibe et al 2014), but it is still unclear which photoreceptors play a role in receiving red and blue light and what reactions are involved between perception of light and rhythmic flower opening. Another report showed that a relatively slow phytochrome reaction is involved in the perception of the duration of light or darkness (Lumsden 1991).…”

“…In the Asiatic hybrid lily, flower opening has been shown to proceed irregularly if it was kept in continuous darkness, indicating the importance of changing from light to darkness for appropriate timing of flower opening (Bieleski et al 2000). In the hybrid tea rose, Horibe et al (2014) reported that flower opening showed a diurnal rhythm under a 12-h photoperiod and constant dark conditions, although rhythmic flower opening under constant dark was not as clear as that of cut flowers kept under 12-h light and 12-h dark cycles. However, cut roses maintained under constant light did not show rhythmic growth and kept opening slowly until fully opened.…”

“…Chin and Sacalis (1977) reported that 14C-sucrose, when taken up into the xylem, moved rapidly into leaves and flower heads of cut roses and that invertase located in the xylem involved in the rapid hydrolysis of sucrose. Horibe et al (2014) showed that most of the Flower opening physiology of cut roses 11 ____________________________________________________________________________________________________________________ exogenously applied glucose first moved to leaves, where it was converted to sucrose, and then synthesized sucrose was translocated to petals as reported in Eustoma , and rose and carnation (Paulin & Jamain 1982). Plenty of soluble carbohydrates accumulate in leaves after sugar treatment, but there seems to be partial carbohydrate translocation to petals (Horibe et al 2014).…”

“…Horibe et al (2014) showed that most of the Flower opening physiology of cut roses 11 ____________________________________________________________________________________________________________________ exogenously applied glucose first moved to leaves, where it was converted to sucrose, and then synthesized sucrose was translocated to petals as reported in Eustoma , and rose and carnation (Paulin & Jamain 1982). Plenty of soluble carbohydrates accumulate in leaves after sugar treatment, but there seems to be partial carbohydrate translocation to petals (Horibe et al 2014). Therefore, promoting sugar translocation from leaves to petals would improve cut flower quality and elevate the positive effects of sugar treatment.…”

Postharvest physiology of cut flowers

“…Similarly, orchids (Cymbidium hybrid 'Red Princess') treated with 5% sucrose pulsing had a longer vase life of 56 days (De et al, 2014). In addition, Horibe et al (2014) also showed the importance of leaves in the translocation of sugar. Flowers cut from roses with leaves had a higher soluble sugar content in the petals compared with cut flowers without leaves.…”