Pulverized black pepper seeds were evaluated in the lab
oratory for toxicity, reduction of Fi progeny and repellency
effect against aduflts of Sitophilus oryzae (L.), Rhizoper—
tha dominica (F.) and ‘ribolium castanetun (Herbst.). Data
showed that black pepper powder was very toxic to . y
and gave complete protection to stored wheat after 7 days
from the treatment. Whereas, it had relative toxic effects
against T. castaneum (73%), and moderately toxic to R.
dominica adults at 4% concentration for the same period.
Reduction of the Fi generation at concentrations between
l—4% was in the range of 100%, 38—91% and 42—78% for S.
T. castaneujn and R. dominica, respectively.
Potential repellency of the pepper powder was very obvious
to T. castaneum adults at all tested concentrations. While
the repellency effect to R. dominica and S. oryzae adult
was only high at 2 and 4% concentrations. The results indi
cated that black pepper powder could be used as a protectant
for grain against certain stored product insects.