1 research outputs found
Evaluation of ethanolic extract of Zanthoxylum xanthoxyloides (Lam) as seed protectant against Callosobruchus maculatus (F.) and Sitophilus zeamaismotsch. on stored cowpea and maize under tropical conditions
The efficacy of Zanthoxylum xanthoxyloides stem bark and root bark ethanol extracts as grain protectant against Sitophilus zeamais and Callosobruchus maculatus was investigated in the laboratory under ambient conditions. The root extract was more effective in controlling both insects, and it was more toxic to C. maculatus than S. zeamais. Insect mortality was dosedependent. After 24 hours, the highest dose of 50% stem extract evoked 55% and 85% mortalities in S. zeamais and C. maculatus, respectively; while 50% root extract evoked 97.5% and 100% mortalities in S. zeamais and C. maculatus, respectively. Development of eggs and immature stages within the treated seeds as well as progeny emergence significantly decreased with increasing dosage of both extracts. Emergence of C. maculatus was completely inhibited by 30% treatment of both extracts, while for S. zeamais inhibition was achieved at 40% treatment. The effect of the secondary metabolites present in Z. xanthoxyloides responsible for its efficacy is investigated and discussed. The potential use of Z. xanthoxyloides as insecticidal, feeding and oviposition deterrent to protect the stored product is discussed. Keywords: Sitophilus zeamais, Callosobruchus maculatus, Zanthoxylum xanthoxyloides, secondary metabolites, mortalit