Food security: Assessment of insecticidal potentials of ethanolic extracts of Capsicum chinense and Chromolaena odorata as protectants of Oryza sativa against weevils infestation

Abstract

Weevil infestations in harvested crops can harm their nutritive value and marketability. While
synthetic pesticides and insecticides can be expensive and hazardous to human health, this study
examined the insecticidal properties of ethanolic extracts from Chromolaena odorata and
Capsicum chinense against Sitophilus oryzae. The researchers extracted fresh leaves, young shoots,
and flowers from C. odorata and tested 2ml of the different concentrations of plant extracts against
S. oryzae. After a 24-hour interval for three days, they determined the mortality rate of S. oryzae in
2ml extracts of Chromolaena odorata and Capsicum chinense. The results indicated that both C.
capsicum and C. odorata showed insecticidal potential, and the effect of the plant extracts varied
as the concentration and time of exposure increased. At 72 hours, both plant extracts resulted in
100% mortality. This study demonstrated the efficacy of C. odorata and C. capsicum ethanolic
extracts as botanical solutions against S. oryzae, a rice weevil. It recommended their commercial
trial for sustainable food security in Nigeria and beyond.