Oviposition Response of Spodoptera exigue to the Extract and Four Fractions in Different Solvents from Artemisia argyi Levl.

The antennae response of female adults of Spodoptera exigua to the crude extract and 4 fractions in different solvents (benzene, ethyl acetate, acetone and ethanol) from Artemisia argyi was investigated by using Syntech electroantenogram apparatus, and the repellent and deterrent characteristics of the crude extract and 4 fractions to S. exigua were measured as well. The results showed that there was significant difference among the crude extract and 4 fractions in the antennae response, with the highest electroantenogram (9.632±1.054 mV) in the fraction in acetone, followed by the fraction in ethyl acetate and the crude extract, and the electroantenogram in the fraction in ethanol was lowest (3.814±0.441 mV). Both the fraction in acetone and in ethyl acetate had significant repellence and deterrence to the oviposition of S. exigua, and the repellent rate and deterrent rate were increased along with the concentrations of the fractions. At 10 mg/mL, the repellent rates of the fraction in acetone and in ethyl acetate were 34.9% and 49.0%, and the deterrent rates of them were 72.16% and 68.95% respectively. At higher concentrations (5 mg/mL and 10 mg/mL), the crude extract, the fraction in benzene and in ethanol also had the deterrence to the oviposition to different extents.