Tree-to-tree variability in fruits and kernels of a Balanites aegyptiaca (L.) Del. population grown in Sudan

Abstract

Correlations were observed between Balanites aegyptiaca fruit morphology and kernel oil yield and quality, thus suggesting the possibility of selecting trees with smaller fruits and lower pulp/seed ratio for edible oil production. Phenotypic variations in fruit morphology (length, diameter, total fruit weight, anatomical part weight percentages) and kernel chemical traits (gross composition, amino acid content, fatty acid composition of kernel oil) were assessed in a natural population of Balanites aegyptiaca (L.) Del. grown in the South-East of Sudan, with the main aim of highlighting the potential of B. aegyptiaca kernel for edible oil production. Mature fruits were randomly collected from eight trees, representative of eight distinct categories for shape (length/diameter ratio) and size (weight). Significant tree-to-tree differences in fruit morphology and kernel composition have been registered. The smallest fruits were characterised by the highest kernel contribution to the whole fruit weight, while the largest fruits showed the smallest seeds. The highest oleic/linoleic acid ratio in kernel oil fatty acids was found in fruits characterized by the lowest pulp percentage; the maximum oil yield (highest kernel percentage and kernel oil percentage) was associated to the highest levels of polyphenolic antioxidants and the highest radical scavenging activity of kernel tissues. Experimental data suggested the possibility of selecting trees with large fruits and high pulp/seed ratio, suitable for direct consumption as human food, and trees with smaller fruits and lower pulp/seed ratio for oil production.