Micropropagation by Repeatedly Inducing Axillary Bud Formation of Different Gene Dosage Purple Coneflower Plants

A strategy of repeatedly inducing axillary bud formation from bud explants was tested for micro propagation of purple coneflower (Echinacea purpurea L.) of different gene dosages. It was found that explants of lower gene dosage required lower concentrations of cytokinin (BA) and auxin (NAA) to achieve higher propagation rate of axillary buds, and with the most suitable BA and NAA concentrations tested, haploid had much higher propagation rate than tetraploid, while the propagation rate of diploid was much closer to that of haploid than to tetraploid. By the established culture protocol, about 1,500,000 haploid, 1,200,000 diploid and 600,000 tetraploid plantlets can be theoretically propagated from one explant in one year.