Published Research · IJPSS · 2026
DATA ANALYSIS PORTFOLIO · YAKUBU ABUBAKARI

Effect of Azadirachta indica (Neem)
on Cowpea Weevil Mortality & Seed Damage

ANALYST Yakubu Abubakari
INSTITUTION C.K. Tedam University of Technology & Applied Sciences
DOI 10.9734/IJPSS/2026/XXXXX
Key Findings
Peak Mortality
14.5%
Neem Fruit 45g at Day 28 — highest recorded mortality across all treatments
Seed Damage Reduction
94%
Neem Fruit 45g reduced seed damage from 35.24 to 2.06 damaged seeds vs control
Most Effective Type
Fruit
Powder
Neem fruit powder consistently outperformed leaf powder across all doses and timepoints
Optimal Dose
45g
Highest dose showed greatest efficacy — mortality and seed protection both maximised
Mortality Analysis
Mortality at Day 28
MEAN % BY TREATMENT & DOSE
Neem Fruit Powder
Neem Leaf Powder
Control
Mortality Over Time
45G DOSE — FRUIT vs LEAF vs CONTROL (DAYS 7–28)
15% 10% 5% 0% Day 7 Day 14 Day 21 Day 28 14.5% 8.0% 1.0%
Fruit 45g
Leaf 45g
Control
Seed Damage Reduction at Day 28
Mean Number of Damaged Seeds by Treatment
LOWER VALUES = BETTER PROTECTION · COMPARED AGAINST CONTROL (35.24 SEEDS)
Analytical Insights
INSIGHT 01
Dose-response relationship confirmed. Across both Neem fruit and leaf powder, higher concentrations (25g, 45g) produced significantly greater mortality and lower seed damage than the 15g treatment, consistent with a classical dose-response curve.
INSIGHT 02
Fruit powder outperforms leaf powder. At equivalent doses and timepoints, Neem fruit powder consistently achieved higher mortality percentages than leaf powder, suggesting a higher concentration of bioactive compounds in the fruit fraction.
INSIGHT 03
Seed protection is dose-dependent. The 45g fruit powder treatment reduced damaged seeds to just 2.06 at Day 28, compared to 35.24 in the control — a 94% reduction, demonstrating strong practical application for smallholder grain storage.
INSIGHT 04
Leaf powder shows anomalous seed damage increase. Unlike fruit powder, leaf powder at 15g recorded higher seed damage (18.5) than the control at Day 28 (35.24 → baseline higher at Day 28), suggesting possible attractant effects at low doses — warranting further investigation.