Adventitious Root Development in Ornamental Plants: Insights from Carnation Stem Cuttings

Abstract

Adventitious rooting is an important factor ensuring vegetative propagation of a number of plant species. Carnation is, after rose, the most important species on the worldwide market of cut flowers. Our current knowledge about adventitious rooting in carnation has gain insight from physiological studies, showing that root induction in the cutting is affected by complex interactions between sucrose and hormone levels, particularly auxin. However, the genetic determinants of the differences found in rooting performance between carnation cultivars are still unknown. We are developing new approaches to characterize in detail stem cutting morphology and adventitious root (AR) architecture in carnation cuttings. Recent developments in sequencing technologies allow genome-wide genetic variation discovery among landraces and cultivars, which can then be used for the discovery of trait-linked markers through genome-wide association (GWA) studies. The identification of the genes involved in AR formation in this species will help establishing a marker-assisted selection (MAS) approach to select for improved adventitious rooting performance in current carnation breeding programs.