Abstract:
Cowpea (Vigna unguiculata), a strategic legume in sub-Saharan Africa, suffers significant
post- harvest losses due to infestations by the beetles Callosobruchus maculatus and
Bruchidius atrolineatus. In this study, we evaluated the bioactivity of three essential oils
(EOs)—green mint (Mentha spicata), basil (Ocimum basilicum) (both lab-extracted), and a
commercial eucalyptus EO—on key biological parameters of adult beetles.
Results demonstrated significant repellency across all EOs, with the weakest effect observed
for eucalyptus. Contact and fumigation bioassays quantified their impact on adult survival and
emergence. The findings confirm that these natural bioinsecticides offer a sustainable
alternative for post-harvest protection, particularly in rural settings.
