Aim: The study aimed at assessing the LD₅₀, fecundity and locomotor effects of Ximenia americana L in Drosophila melanogaster.

Study Design: The study was an experimental design.

Place and Duration of Study: The study was done in the drosophila laboratory, Africa Centre of Excellence in Phytomedicine Research and Development (ACEPRD), University of Jos, Nigeria between November 2019 and Match, 2020.

Methods: The experimental animals (1-3 days old) of both sexes were exposed to different concentrations (1 mg 10 mg 50 mg, 100 mg, 200 mg, 250 mg 300 mg, 350 mg, 400 mg, 450 mg) of the plant extract per oral for seven days to determine the lethal dose, LD₅₀. Thereafter, five days treatment was done using 50 mg, 100 mg 200 mg and 300 mg concentrations of the extract to assay for fecundity and locomotor effect in the fruit fly.

Results: The LD₅₀ of the methanol extract of Ximenia americana in D. melanogaster was found to be 327.7 mg, this showed that the plant extract is relatively safe. Also, the result showed that both fecundity and locomotor behaviour of the treated and untreated flies was not significantly (P > 0.05) different. Thus, the extract at the used concentrations does not affects significantly both the reproductive capacity and the motor functions in the fruit fly.

Conclusion: All the tested concentrations used in this research are relatively safe (because of high LD₅₀ 327.7 mg) in the fruit fly and slightly increase the emergence of new fly with no noticeable negative effect in locomotor activity.