Ex vitro vegetative propagation technique for sustainable utilization of Hypoxis hemerocallidea corms

Abstract

Hypoxis hemerocallidea is a highly utilized medicinal plant, with the potential to treat testicular tumors, prostate hypertrophy and urinary infections. Although currently classified as of least concern in its conservation status, its ongoing, unsustainable harvesting and habitat loss remain threats to its natural populations. The potential of using one-half of H. hemerocallidea corms for propagation and the other half for medicinal purposes was investigated in an effort to develop sustainable utilization strategies for this plant. The corms were cut transversely into upper and lower halves, following which the upper halves were either cut into four or eight equal segments, or used without any further cutting. The segments were soaked for 30 min in 6-benzyladenine (BA) or gibberellic acid (GA3) at concentrations of 50 or 100 mg/L, while soaking in distilled water served as the control. Upper parts of the corm cut into four segments, and soaked in 50 mg/L BA resulted in a high number of cormlets. The propagation coefficient of the upper corm parts cut into four segments and soaked in 50 mg/L BA was 140%. The cutting method alone or combined with plant growth regulator treatments significantly affected the number of cormlets produced. Cutting the upper corm parts into four segments and soaking in distilled water resulted in a propagation coefficient of 90%. Cutting the upper corm parts into four segments is advantageous as the segments are not too small to compromise food reserves, while soaking allows for the leaching out of possible growth retardants. The study successfully developed a method, which can be recommended for sustainable harvesting and propagation of H. hemerocallidea.