Research Journal of Agronomy
ISSN: Online 1993-6060ISSN: Print 1815-9354
Abstract
Powders of bitter leaf, cashew leaf, orange peel and pawpaw leaf were tested at 2.5, 5.0 and 7.5% (w/w) for their insecticidal actions against bean beetle, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) in the laboratory. Results showed that the ovicidal and adulticidal actions of the plant powders depended on dosages and exposure time. Mortality of 16.28 and 18.75% were observed in bitter leaf powder applied at 7.5% (w/w) dosage within 24 and 48 h post infestation (HPI), respectively. In grains treated with 7.5% orange peel powder, 12.50 and 16.28% mortality were observed with in 24 and 48 HPI, respectively. Each of bitter leaf and orange peel powders was significantly different (p<0.05) in causing adult mortality at highest dosage compared with the control. No mortality was observed in the control within 48 HPI. Oviposition was inhibited in the highest dosage of the plant powders but the percentage oviposition in the lower dosages was three-fold lower than the control. The plant powders also significantly reduced progeny emergence and grain damaged by the beetle. No progeny emergence was observed in grains treated with bitter leaf powder at 27 days post infestation. Cashew and pawpaw leaf powders caused grain damage of 46.3-54.7 and 44.7-60.7% within three months of storage, respectively. There was decrease in insecticidal effects of the plant powders as indicated: bitter leaf>orange peel>ashew leaf>pawpaw leaf. It is recommended that incorporating these plant powders in pest management of stored products will guarantee user safety, confer ease of application, reduce environmental pollution and suppress insect infestation under small scale storage.
How to cite this article:
A.K. Musa and R.O. Uddin. Insecticidal Potential of Indigenous Plant Powders Against Beetle, Callosobruchus maculatus
(F.) (Coleoptera: Chrysomelidae) in Stored Cowpea.
DOI: https://doi.org/10.36478/rjagr.2017.1.5
URL: https://www.makhillpublications.co/view-article/1815-9354/rjagr.2017.1.5