[Chemical components of volatile oil from Mikania micrantha and its biological activity on insects].

The chemical components of volatile oil from Mikania micrantha were analyzed by GC/MS. Twenty-two compounds were identified, and monoterpenes and sesquiterpenes as well as alcohol and ketone with their derivatives were major components. Biological activity of volatile oil on insect was investigated. The results showed that the volatile oil had significant deterrent effect on oviposition of Plutella xylostella, Phyllotreta striolata and Phaedon brassicae at dose of 5-10 microliters.plant-1. They also possessed established contracting toxicity, and their rectifying reduce rates for Lipaphis erysimi were 50.0%, 59.86%, 62.51% at concentration of 500, 750, and 1000 mg.L-1, respectively. However, they had not fumigating toxicity for virginogeniae, L. erysimi, 2nd instar larvae of P. xylostella, and adult of P. striolata at concentration of 500 mg.L-1.