Abstract:
The effect of atmospheric condition produced by candle jar method on the
mortality of adult red flour beetles, Tribolium castaneum Herbst, was evaluated for a
period of five days. Storage atmosphere was modified to 5% carbon dioxide and 16%
oxygen using candle jar method. The degree of activity or the general body movement
was rated. The percent mortalities on the fifth day of exposure including the daily
mortalities produced in the candle jar method set-ups were determined. The viability of
eggs was determined through the presence or absence of larvae after 14 days following
the separation of food medium to the treated adults. Although carbon dioxide
concentration increased from 5% tol10% and 0% to 8% for candle jar method and normal
enclosed atmosphere set-ups respectively, results on both treatments had no significant
difference to that of the open-air treatment. In the three treatments, almost all beetles
remained submerged in the food medium in the whole duration of the experiment. The
percent mean mortalities produced in the treatments were not greater than 4%. All food
media contained larvae. These results were probably because the experimental treatment
failed to reach 15% carbon dioxide and about 6% oxygen environment, a condition that
exhibited synergistic effect as reflected by the 100% mortality produced in the enclosed
control within preliminary experiment of ten days. Candle jar method is therefore not
effective in controlling adult red flour population within this time frame.
