Effect of plant growth regulators on shoot organogenesis and somatic embryogenesis of Echinacea purpurea L.

Echinacea is an indigenous herbal plant genus of north america and occupies an important place among medicinal plants due to its immunostimulatory properties against respiratory ailments. the increasing demand for high-quality plant material has necessitated its true to type,disease-free propagation through tissue culture. in vitro regeneration potential of different plant growth substances for echinacea purpurea l. was investigated in this study. the e. purpurea was evaluated for its morphogenic potential in different concentrations and combinations of plant growth regulators. seeds of e. purpurea were grown in magenta boxes containing murashige and skoog (ms) basal medium under controlled conditions and leaf discs (1.5×2.0 mm) were used as explants in these experiments. explants were excised and cultured under aseptic conditions on nutritional medium containing ms salts and b5 vitamins mixed with combinations of 1.0-5.0μm bap,1.0-5.0μm iba,and 0.1-1.0μm tdz. the cultures were kept in a growth cabinet with cool white light (40-60 mol.m-2.s-1) under 16-hr photoperiod. regeneration was quantified at 28 days based on the degree of shoot organogenesis and somatic embryogenesis. different concentrations and combinations of different types of plant growth regulators showed the different response for in vitro regeneration of e. purpurea. these investigations would aid in the development of a model system for clonal mass propagation and in vitro regeneration of echinacea spp.