Combining air-layering and stem cutting techniques to optimize the production of quality planting materials for agroforestry tree species: a case study of Canarium schweinfurthii Engl. (Burseraceae)

ABSTRACT Using Canarium schweinfurthii as biological model, the present study evaluated the potential of combining air-layering and stem cutting techniques to optimize the production of agroforestry trees’ propagules. Three substrates and five concentrations of indole butyric acid (IBA) were tested for their effects on the rooting of air-layers. Stockplants were raised from air-layered propagules and used for stem cutting trial. Three levels of stockplant irradiance and five IBA concentrations were tested for their effects on the rooting of stem cuttings. Results showed that the combination of Sawdust substrate and 5 g/l IBA resulted in highest percentage of rooted layers (79.3 ± 7.6%) and highest number of roots per rooted layer (34.9 ± 0.7). Sawdust recorded the lowest layers’ mortality rate (6 ± 1.9%). Alive cuttings sprouted and rooted at 100%. The lowest mortality rates of cuttings (14 ± 4.8%) and the highest number of roots per rooted cutting (25.5 ± 0.1) were recorded with 10 g/l IBA × 50% ambient sunlight treatment combination. Using air-layered propagules for stockplant production could make it easy to achieve stockplant management practices like shading. Combining air-layering and stem cutting techniques enhanced the multiplication rate of propagules. This provides valuable insights for tree domestication practices worldwide.