Insecticidal activity of extracts from forty-eight plants including Xanthium sibiricum Patrin.

Insecticidal activity of extracts from forty-eight plants against to Plutella xylostella L.was studied by dipping method.Contact toxicity activities of different solvent extracts from Xanthium sibiricum Patrin.against to P.xylostella and Aphis gossypii Glover and different partitioned extracts of acetone extract from X.sibiricum against to P.xylostella were also researched.The results show that 500 g·L-1 acetone extracts from Artemisia annua L.,Euphorbia helioscopia L.,Lagopsis supina(Steph.ex Willd.)Ik.-Gal.ex Knorr.,X.sibiricum and Humulus scandens(Lour.)Merr.possess better toxicity activity to P.xylostella.In different solvent extracts from X.sibiricum,the toxicity of acetone extract is the highest,that of ethyl acetate and alcohol extracts are the second.Toxicity activity of 50 g·L-1 chloroform partitioned extract of acetone extract from X.sibiricum against to P.xylostella is the highest,and the adjusted mortalities for 24 h and 48 h are 88.33% and 91.67% respectively.