Abstract

This study assessed the effects of provenance, tapping incision, and year of harvest on gum yield and growth traits of S. senegal at the Rubber Research Institute of Nigeria, Gum Arabic Sub-Station, Gashua, Yobe State. During the 2012 to 2014 gum collection seasons, the experiment was conducted using a Randomized Complete Block Design (RCBD) with three replications, evaluating 45 trees per S. senegal provenance, with 15 trees per replication. Results showed that I7 (seven incisions) produced the highest gum yield (424.42 g/tree/year and 471.53 kg/ha/year), significantly outperforming I3 and I5. Provenance had a significant influence on bark thickness, with trees from Damaturu having the thickest bark (0.75 cm) and the greatest height (453.77 cm). Year also had a strong effect on yield, with the highest yield recorded in 2013 (406.56 g/tree/year), compared to the lower yield in 2014 (167.42 g/tree/year). Significant interactions between provenance and year suggest that the best-performing provenances varied with environmental conditions. These findings indicate that selecting provenances with thicker bark and optimizing tapping intensity can enhance gum production, providing a foundation for breeding programs aimed at improving S. senegal yields in semi- arid regions.