Flower senescence in composite flowers, can understanding how dahlia florets senesce help to increase dahlia vase life?

Abstract

The dahlia is popular as an ornamental garden plant in the UK, however its value as a cut flower has been undermined by its short vase life. The vase life of dahlias is often no more than 5 days, whereas 10-14 days are required by the cut flower industry due to the supply chain involved in transporting cut flowers from growers to retailers, sufficient time in store, and still guaranteeing 5 days vase life to a consumer. The current study has considered ethylene sensitivity and how phytohormones interact with one another during the senescence process. In conjunction with these traditional methods RNA sequencing and de-novo assembly of the dahlia transcriptome in the cultivar 'Sylvia' has been carried out resulting in an assembly of over 20 000 genes, many of which change in expression during floret senescence.

Senescence in dahlia flowers is regulated by a complex interplay between flower age and floret position

“…; Mohd Salleh et al, 2016) and the dahlia's close relative chrysanthemum (Guo et al, 2003). In dahlias, treatment with cytokinins also seems to be effective in delaying flower senescence in a range of cultivars tested (Shimizu-Yumoto & Ichimura, 2013;Casey et al, 2019) and may act to increase acid invertase activity and sugars (Shimizu-Yumoto et al, 2020). Moreover, inhibiting the degradation of endogenous cytokinin levels also delays floral senescence in carnations (Taverner et al, 2000) and wallflowers (Mohd Salleh et al, 2016), as did increasing endogenous biosynthesis of cytokinins through transformation of petunias (Chang et al, 2003).…”