Laboratory experiments were carried out on the relative toxicity of
Capsicum fruits (Capsicum spp.), Clerodendron (Clerodena’ron inerme),
Eucalyptus (Eucalyptus glob utus) and Duranta leaves Doranta plumieri) against
the adults of cowpea beetle (C’allosobruchus maculatus, F.) using various
concentrations of 10, 5, 2.5, 1.25 and 0.625% (w/v) with extracts and 4, 2 and
1% with plant powders to evaluate mortality, reduction in Fi Progeny and
repellency effect.
Results showed that mortalities of acetone and petroleum ether extracts
were somewhat higher at the highest concentration of 10%, whereas the
capsicum extracts were the most effective one. Petroleum ether extract was mo*’e
effective on mortalities and reduction in F1 progeny than acetone extract.
Plant powders indicated lower effects on mortalities and reduction in
progeny in comparison to the extracts. During the observation period of 15 days,
extracts at various concentrations had low mean average repellency effects
ranged from 17-37% and 16-32% for petroleum ether and acetone extract,
respectively.
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