ISHS Acta Horticulturae 813: VI International Symposium on New Floricultural Crops
PROPAGATION OF HELICHRYSUM OBCONICUM DC. AND HELICHRYSUM DEVIUM JOHNS. FROM CUTTINGS |
| Author: | M.J. Oliveira Dragovic |
| Keywords: | epidermal layer, indole-3-butyric acid (IBA), potassium salt of IBA (KIBA), powder formulation of IBA (Seradix), rooting |
| Abstract:
Helichrysum obconicum and Helichrysum devium are endemic plants of Madeira Island with proven capability as ornamental plants. Several experiments were conducted with mature apical cuttings from both species, in order to determine the best commercial propagation procedures. For H. obconicum the removal of 1 cm of the epidermal layer from the lower part of the cutting increased significantly the rooting percentage; especially when combined with a dipping in a KIBA solution; however, there were no significant differences between the KIBA concentrations tested (500, 1,000, 2,000, 4,000 and 8,000 mg L-1) (64-85% and 76-95% after 2 and 3 months, respectively). Higher rooting percentages were obtained with lower dipping times, but there were no significant differences between 5, 10 and 20 seconds. In the case of H. devium, the removal of 1 cm of the epidermal layer from the lower part of the cutting fastened the rooting of the cuttings. A 5-second dipping in different IBA concentrations did not improve the rooting percentages; there were no significant differences between 0, 500, 1,000 and 2,000 mg L-1 (46.9-51.6 and 79.7-95.3% after 2 and 3 months respectively), but only between any of those concentrations and 4,000 mg L-1, which gave the lowest rooting percentages (12.5 and 34.4% after 2 and 3 months respectively). The best procedure to propagate H. obconicum, is to remove 1 cm of the epidermal layer from the lower part of mature apical cuttings collected from January to March, followed by a 5-second dip in KIBA at 500 to 2,000 mg L-1 solution, and for H. devium to remove 1 cm of the epidermis of mature apical cuttings collected from August to November, and not to apply auxin as this conferred no advantage. | |
Download Adobe Acrobat Reader (free software to read PDF files) | |
