Studies on tissue and cell cultures for plant regeneration of purple coneflower (Echinacea purpurea L.)

Abstract

Explants of leaf, root and petiole were taken from in vitro grown Purple coneflower (Echinacea purpurea L.) plants and their regeneration ability was compared by culturing these explants on media with various supplements. The regeneration ability in root and petiole explants was higher than that in leaf ones, and a combination of 0.3 mg/l benzyladenine (BA) with 0.01 mg/l naphthaleneacetic acid (NAA) in Murashige and Skoog (MS) basal medium was the most effective, yielding 100% shoot regeneration frequency and associated with the highest number of 1.84 shoots per explant. Explants with higher chromosome level need higher cytokinine concentration to achieve higher regeneration frequency. In the experiments, haploid and diploid plants showed higher regeneration potential at 0.3 mg/l BA whereastetraploid (2n=44) required a higher BA concentration of 0.5 mg/l to accelerate the ability. All explants from two and a half months old plantlets produced buds in high frequency; 1143.9 buds were regenerated from 1g explants. With the established regeneration culture system, it was possible to obtain a large number (1124864) of buds within one year period from one mother plant. For initiation of roots from the regenerated shoots and stimulation of growth of the plantlets, all shoots from different explants responded equally well on medium with 0.01 mg/l NAA.