Improved shoot organogenesis and plant regeneration of Echinacea angustifolia DC.

We established an improved method for shoot organogenesis and plant regeneration from stem cultures of Echinacea angustifolia DC. The regenerated shoots obtained from stem cultures on solid MS medium containing different concentrations of BAP and kinetin. The highest number of shoots per explant (3.2) and shoot length (1.3 cm) was obtained on MS medium containing 2 mg/l BAP. The addition of auxins in MS medium containing 2 mg/l BAP substantially improved the shoot regeneration of E. angustifolia and at the optimal concentration of 0.5 mg/l IBA was the most suitable auxin for the highest number of shoots per explant (4.6) and shoot growth (1.5 cm). Plant regeneration was found to be more efficient when Phytagel was used as the gelling agent. The number of shoots produced per leaf explant was 12% higher, and the growth of shoots was 11% greater, on 3 g/l phytagel compared to 7 g/l phytagar. The rooted plants were hardened and transferred to soil with an 80% survival rate. The production of E. angustifolia regenerated plants could be used as a possible transformation protocol.   Key words: Echinacea angustifolia DC, plant regeneration, shoot organogenesis.