Antifeedant and repellent properties of Chaste tree, Vitex negundo and Goat weed, Ageratum conyzoides against Tea mosquito bug, Helopeltis theivora Waterhouse
Abstract
Both the plant extracts with chloroform gave the highest antifeedant property and repellency. The spots produced by two nymphs (179.50) within 24 hours were reduced to (20.25–28.50 & 27.5037.50) with chloroform extracts of V. negundo and A. conyzoides at 5.0–1.0% concentrations, respectively. The other two solvent extracts gave significant results. Likewise, the repellency was observed and found that V. negundo with chloroform resulted the highest repellency (100%) followed by petroleum ether and methanol extracts of the same order. The other plant extracts too showed significant repellent effect compared to control.
Keywords
Ageratum conyzoides, Helopeltis theivora, Plant extracts, Vitex negundo