Insecticidal activity of extracts from Anisodus tanguticus

The insecticidal activity of the extracts against Mythimna separate,Pieris rapae and aphids was studied through insect body and leaf disc immersion method.The results showed that methanol extract from leaves of A.tanguticus had the strongest contact toxicity against 5th instar larvae of M.separate,the next was methanol extracts from stems and root barks,corrected mortality was 28.09%,18.30% and 17.07% respectively when methanol extracts were diluted fivefold.The methanol extract from leaves had the strongest contact toxicity against 4th instar larvae of P.rapae,the next was methanol extracts from stems and root barks,corrected mortality was 66.67%,64.29% and 60.00% respectively when methanol extracts were diluted tenfold.Methanol extracts from leaves,stems and root barks had very weak antifeeding effects against the larvae of P.rapae,the extracts had contact toxicity against Sitobion avenae to some extent,and no contact toxicity against Aphis gossypii as well as Myzus persicae.