Vegetative Propagation of Picralima nitida (Stapf.) by Leafy Stem Cuttings: Influence of Cutting Length, Hormone Concentration and Cutting Positions on Rooting Response of Cuttings

Abstract

Picralima nitida is a valuable tree species in the humid zone of West and Central Africa whose natural regeneration is threatened by seed dormancy and over exploitation. This study investigated the rooting ability of P. nitida using mature leafy stem cuttings. Two cutting length (6 and 8 cm), cutting positions (apical and basal) and three concentrations (0, 0.1 and 0.2 mg/l) of Indole-butyric acid (IBA) were evaluated using a split-split plot design. The result showed that cutting length of 8 cm significantly influenced percentage of rooted and callused cuttings than cutting length of 6 cm.  Significantly higher number of roots occurred in 8 cm cutting length than 6 cm cutting length. Cutting positions significantly affected percentage of callused cuttings only. Cuttings treated with IBA significantly enhanced rooting percentage, number of leaves and shoot height than untreated cuttings. Interactive effect of cutting positions, cutting length and IBA concentration was significant for only rooting percentage. Mature leafy stem cutting of P. nitida can be propagated asexually using cutting length of 8 cm from any position on the shoot to improve the rooting success.  Stem cuttings of P. nitida should be treated with IBA to enhance the rooting capacity of the species