Efficacy Evaluation of Eight Bio-Pesticides and two Synthetic Pesticides in the Control of Cowpea Weevils (Callosobruchus maculatus) and Mold in Sokoto State, Northwest Nigeria

DOI: 10.22161/ijeab.111.15

Abstract:
Two laboratory experiments to evaluate the efficacy of eight bio-pesticides (Plant derivatives) and two synthetic pesticides in mitigating post-harvest losses caused by cowpea bruchids (Callosobruchus maculatus) and storage mold were carried out in Illela, Sokoto state, Northwest Nigeria. The research used a completely Randomized Design (CRD) experiments with ten (10) treatments replicated four (4) times. The efficacy of each treatment was evaluated against egg oviposition, seed perforation, weight loss and mold infestation levels across both restricted and unrestricted weevil attack. The result of the experiment showed significant treatments effect across all parameters taken (P≤0.05). Phostoxin significantly demonstrated absolute potency under restricted condition, achieving complete inhibition of egg oviposition (0.00 egg). However, under unrestricted infestation condition, the absolute potency of phostoxin in inhibiting egg oviposition observed under restricted infestation was broken as up to 483.00 eggs were laid, but still maintain absolute potency in inhibiting seed perforation (0.00 holes) as the eggs failed to hatch. A combination of mancozeb 80%WP and Acetamprid 40% proved dual significant control against bruchid and fungal infestation throughout the storage period. Regarding bio-pesticides, turmeric proved significantly superior in reducing egg oviposition by 84.53% (152.45 as against 986.01 in the control and also reducing seed perforation by 76.90% (14.81 as against 64.00 exit holes). Again, grape peel powder also exhibited significant deterrent effect by reducing egg oviposition by 83.77% (160.03 as against 986.01 eggs in the control) and in seed perforation by 73.05%. Regarding storage mold infestation, Alligator pepper recorded significantly higher antifungal potency than other bio-pesticides achieving near total mold suppression (1.00 infested seed).

Keywords:
Cowpea (Vigna unguiculata), Bruchids (Callosobruchus maculatus), Bio-pesticides, synthetic pesticides, mold.

Article Info:
Received: 13 Jan 2026; Received in revised form: 15 Feb 2026; Accepted: 20 Feb 2025; Available online: 28 Feb 2026

Cite this Article: