Effect of sub-lethal concentrations of lufenuron on growth, development and reproductive performance of tribolium castaneum (herbst) (coleoptera: tenebrionidae).

ABSTRACT

The effect of the chitin synthesis inhibitor lufenuron on the various developmental stages of red flour beetle Tribolium castaneum was determined by exposing them to different sub-lethal concentrations (LC10, LC20 and LC40) of lufenuron through diet for 24 hrs. There was a dose dependent effect on the larval weight, time taken for pupation, and adult emergence, percentage pupation and percentage adult emergence. When two day old larvae were fed on sublethal concentrations through diet a small proportion of pupal –adult intermediates were observed at LC20 and LC40. Adults emerging from the larvae fed on diet containing LC10, LC20 and LC40 of lufenuron did not show any variation in the fecundity and hatchability of eggs from that of control. The fecundity of adults fed with sub-lethal concentration of lufenuron (obtained against two day old larvae through diet) was not affected, however, percentage hatching and survival was affected. Interestingly there was a reversal of the effect within ten days of treatment with respect to percentage hatching and survival. When eggs were exposed to treated diet hatching was not affected. The present data suggest that lufenuron even at sub-lethal concentrations has a very good larvicidal and ovicidal activity in T. castaneum.