Establishment of an Efficient In Vitro Culture System in Dicentra × hybrida

Dicentra, known as bleeding-hearts, is a genus of eight species of herbaceous plants, native to eastern Asia and North America. It is a member of the Fumariaceae botanical family, sometimes referred to as a subfamily of the Papaveraceae (the poppy family). Dicentra × hybrida is a popular ornamental hybrid, cultivated in parks and gardens worldwide. To date, there are no reports on establishing a plant tissue culture system in this species. In Dicentra, all leaves are in a basal rosette which hinders the disinfection process. At the same time, cautious treatments are required not to damage the delicate tissue. The aim of this study was to develop an efficient tissue culture system in D. × hybrida ‘Amore Rose’ for the purpose of further micropropagation. Shoots of in vivo­-grown plants were dissected and washed with running tap water. Next, shoot segments were bathed in tap water with a drop of detergent for 30 min and, then, immersed in 70% (v/v) ethanol for 1 min. Following the initial disinfection, explants were surface sterilized with 0.4 – 0.8% (v/v) sodium hypochlorite (NaOCl) for 20 min and, finally, washed thrice with sterile distilled water (20 min each). The treated rosette explants were inoculated polarly in the modified Murashige and Skoog medium devoid of plant growth regulators and cultured in a growth room with 16-h photoperiod. After one month, contamination-free explants were transferred on the kinetin-supplemented medium. The disinfection efficiency reached 20 – 40%. All disinfected explants were capable to develop healthy shoots. The multiplication ration, i.e. number of secondary explants produced, reached 4.3. All developed shoots regenerated roots spontaneously. The described here protocol can be recommended for in vitro propagation of Dicentra × hybrida. Further studies should focus on inducing adventitious organogenesis from leaf explants of the in vitro-derived plant material.