Bioactivity of extracts from Artemisia argyi and Melia azedarach against Biston marginata

Bioactivity of the ethanol,petroleum ether and acetidin extracts from Artemisia argyi and Melia azedarach against the 3th instar larvae of Biston marginata were tested by dipping leaves and dipping insect method in laboratory. The results showed that the extracts of three solvents from A. argyi and M. azedarach had some bioactivities against the 3th instar larvae. When the concentration of extracts was 120 g/L,the antifeedant activity and the corrected mortality of the ethanol extracts from A. argyi were 84.01%,and 85.00%,respectively,the antifeedant activity of the ethanol extracts from M. azedarach was higher with an antifeedant rate of 81.77%,the insecticidal activity of the acetidin extracts from M. azedarach was the highest with a corrected mortality of 80.00%. Further toxicity analysis showed that the insecticidal activities of ethanol extracts from A. argyi and acetidin extracts from M. azedarach were stronger,with LC50 value of 34.595 g/L and 42.020 g/L after 48 hours.