Predicting fruit production of Ziziphus mauritiana Lam. according to phytogeographic zones in Burkina Faso: Implications for promoting the uses potentials and the sustainable management of the species

Fruit of Ziziphus mauritiana Lam. are widely harvested by rural communities for food and income across West Africa sahelian areas. The species is listed among the high value food providing plants in Burkina Faso. However, the lack of reliable assessment of its fruit production is one of the main constraints limiting its valorization and sustainable management. This study aims to analyze factors affecting fruit production of Z. mauritiana and to develop allometric models for estimating this production. Total harvest method was used to quantify fruit from 130 individuals distributed into five diameter size classes across two phytogeographic zones of Burkina Faso, the sub-Sahel and the north-Sudanian. Models were fitted with 80% of sampled individuals randomly selected and 20% were used for model validation. The results showed that fruit production varied significantly according to phytogeographic zone and diameter size class. Mean dry mass of fruit per individual was significantly higher (p = 0.0135) in the north-Sudanian zone (1.82 kg per individual; CV = 164.4%) compared to the sub-Sahel zone (1.65 kg per individual; CV = 184.7%). Diameter at breast height and total height of individuals were the best predictors of fruit production in the sub-Sahel zone. For the north-Sudanian zone, Diameter at breast height, total height and crown diameter of individuals were the best predictors. These results provide evidence that allometric models could be used to successfully estimate the amount of fruit production in Z. mauritiana. This is interesting for perspectives of exploitation planning and sustainable management of the species resources.