Investigation of explant and plant growth regulators on callogenesis, indirect shoot regeneration and shoot rooting in Echinacea angustifolia DC

Echinacea is one of the most important medicinal plants and an important source of cichoric acid. In this research, callus induction, indirect shoot regeneration, and shoot rooting of Echinacea angustifolia DC. were investigated. The effects of explant (leaf, petiole and root) and NAA concentrations (0.5, 1 and 1.5 mg l-1) on callus induction as well as the effects of explant (leaf, petiole and root) and BAP concentrations (3, 4 and 5 mg l-1) on the indirect shoot regeneration of callus were evaluated in two separated experiments. The study was conducted as factorial in a completely randomized design (CRD). The effects of IBA concentrations (0.5, 1, 1.5 and 2 mg l-1) on shoot rooting were also investigated in a completely randomized design. The effects of the factors studied on the callogenesis were not significant while these factors had significant effects on the shoot regeneration and rooting at 1% probability level. In general, the results indicated that the highest indirect shoot regeneration (72%) was obtained from the leaf explant and by the use of 4 mgl-1 BAP. In addition, the highest shoot rooting (38% and 40%) was obtained using 1 and 1.5 mgl-1 IBA. The good potential of this species for indirect shoot regeneration was shown in this research. These results can be used in micropropagation programs, gene transfer, and transgenic plants production.