Effect of Ageratum conyzoides on Feeding, Development and Reproduction of Schistocerca gregaria (Forskal)

Ageratum conyzoides extracts have no antifeedant activity against Schistocerca gregaria. Topical application of leaf and whole plant extract to 5th instar nymphs of the test insect caused extended nymphal period, produced nymphal adult intermediates and wing deformities in the adults. Besides, the adults emerged from treated nymphs showed inhibition of ovarian development. Percentage of normal adult emergence was also reduced. Topical application of oil to 4th instar nymphs produced precocious adults apart from causing nymphal mortality.