Influence of the origin of stem cutting, season of collection and auxin application on the vegetative propagation of African Sandalwood (Osyris lanceolata) in Tanzania: scientific paper
AbstractAn investigation into the possibility of propagating O. lanceolata through stem cutting was carried out at Tanzania Tree Seed Agency, Iringa Zone, Tanzania. The aim was to test the potential of stem cuttings in providing an alternative/supplement to the use of seeds that are constrained with germination and storage problems. Three treatments were investigated on the rooting success and subsequent nursery performance of the cuttings: the effect of season at which cuttings are collected i.e. December, February, June and September; the effect of origin of stem cutting in a shoot, i.e. basal and terminal portions; and the effect of different levels of IBA as root promoters, i.e. 0, 50, 100 and 150 ppm. The results revealed that stem cuttings collected from the sprouting stumps have a potential to be used in propagating O. lanceolata. Season at which cuttings are collected; origin of the stem cuttings in a shoot and application of auxins influenced the rooting success. Stem cuttings collected in September, originating from the basal portion had the best rooting (43.8 + 3.9%). This is possibly related to the high levels of stored food in the plant after undergoing active photosynthesis during the rain season, November-May. Auxin application in interaction with the season at which cuttings were collected enhanced the number of cuttings that rooted, the number of roots formed (13 + 0.4), the length (14 + 0.3 cm) and biomass of roots (6.95 + 3.9 g) produced. The concentration to be applied for effective rooting depended on the season at which cuttings were collected. Of the origin of stem cuttings, basal portions had better rooting than the terminal portion. The high nutrition status and low nitrogen content of basal portions may play a role in enhancing their performance. Thus when raising O. lanceolata from stem cuttings, best rooting is obtained from those raised between June and September using cuttings from the basal origin of the juvenile shoots. Application of IBA between 50 and 100 ppm further enhances rooting success.
Key Words: Osyris lanceolata, African sandalwood, Stem cuttings, Collection season, Stem origin, IBA application, Rooting success
Southern African Forestry Journal Vol.201, 2004: 13-24