EFFECT OF DELAYED IBA TREATMENTS ON ROOTING OF PROTEA CULTIVARS 'NIOBE', 'LADY DI', 'PINITA', 'SUSARA' AND 'PINK ICE'
Successful clonal propagation is essential for commercial production of Proteaceae. The standard protocol developed for rooting Proteaceae cuttings has not been successful with all protea cultivars. The purpose of this study was to evaluate delayed application of indole-3-butyric acid (IBA) to improve the propagation of protea cultivars known to have low rooting success. Cuttings were either stored in the dark for 0 to 10 days before treating with IBA or incubated in a rooting environment under natural light without IBA for conditioning periods of 0 to 28 days before application of IBA. Cultivars Protea F2 hybrid Niobe, P. magnifica × P. compacta Lady Di, P. magnifica × P. longifolia Pinita, P. magnifica × P. Susannae Susara and P. compacta × P. susannae Pink Ice were used. More than 80% rooting was achieved with Pink Ice and Susara and these may be described as easy-to-root. The first approach did not increase rooting percentage of the more difficult-to-root cultivars, Lady Di, Niobe and Pinita. Niobe cuttings rooted significantly better with no cold storage period. Although some trends were detected that indicated improved rooting success with delayed IBA treatment after incubation in the rooting house, there was no significant improvement in the number of transplantable cuttings. In both approaches, Pinita had a high percentage of cuttings with no root formation, but without decay or leaf drop.
Blomerus, L.M. and Malan, D.G. (2014). EFFECT OF DELAYED IBA TREATMENTS ON ROOTING OF PROTEA CULTIVARS 'NIOBE', 'LADY DI', 'PINITA', 'SUSARA' AND 'PINK ICE'. Acta Hortic. 1031, 57-66
propagation, cuttings, conditioning, scoring scale