Evaluation of insecticidal potentialities of extracts from Calotropis procera Ait. against Henosepilachna elaterii Rossi

The extractive methods and bioactivity of the extracts from different parts of Calotropis procera was evaluated against African melon ladybird beetle, Henosepilachna elaterii in laboratory. Soxhlet method yielded more extracts than electric shaker method. Leaf produced more extracts than flower and root. Leaf extracts showed stronger bioactivity than those from flowers and roots. The extracts gave complete feeding repellency to the newly hatched larvae. All larvae in fourth instar forced to feed on extract-treated pumpkin leaf died without pupation. Topical application of the extracts from leaves and flowers to the fourth instar larvae increased larval and subsequent pupal mortality of the pest and produced more abnormal adults compared to the control. However, if larvae were forced to feed on extract-treated pumpkin leaf for 2 days only, and then provided with untreated leaf, they were still able to complete their life cycle; their fecundity and life span for the adults resulted from the treatment were not reduced compared to those from the control.