Vegetative propagation of Combretum collinum Fresen. (Combretaceae), Combretum molle R. Br. ex G. Don (Combretaceae) and Piliostigma thonningii Schumach. (Fabaceae) by cuttings: Effects of rooting media and indole-3-butyric acid concentration

Abstract The aim of the current study was to examine the propagation potential of woodland tree species in Uganda. Specifically, the study assessed the rooting of stem cuttings of Combretum collinum Fresen. (Combretaceae), Combretum molle R. Br. ex G. Don (Combretaceae) and Piliostigma thonningii Schumach. (Fabaceae) under different rooting media and Indole-3 butyric acid (IBA). Three rooting media (pine bark, soil-sand and sand) and different concentrations of Indole-butyric acid (IBA) plant growth hormone were considered. Data on rooting, number of roots, root length and root collar diameter were collected. Rooting of C. collinum was highest when treated with IBA and propagated in soil-sand or sand medium while that of C. molle and P. thonningii in soil-sand medium when the cuttings were not treated with IBA. The highest number of roots of C. collinum and C. molle was when they were treated with IBA and propagated in soil-sand or pine bark or sand medium while P. thonningii when the cuttings were not treated with IBA and propagated in soil-sand or sand.The highest root length of the C. collinum, C. molle and P. thonningii was achieved when cuttings were treated with IBA and propagated in sand. The highest root collar diameter of C. collinum and C. molle was when cuttings were treated with IBA and propagated in pine bark while of P. thonningii when cuttings were not treated with IBA and propagated in soil-sand. Propagation of these three species ought to take into consideration the interaction between rooting medium and growth hormone.