EN
The feeding deterrent activity of 1% alcohol solutions of farnesol and its synthetic derivatives against larvae L3 and adults of Leptinotarsa decemleneata Say was studied. In laboratory bioassays 24 h choice and no-choice tests at 24°C under a 16L:8D photoperiod were used. Among compounds tested farnesol and trans-3,7,11-trimethyl-3-vinyldodeca-6,10-dienoic acid were good antifeedants against adults. A strong antifeedant effect against larvae showed farnesol, its acid derivatives and unsaturated γ-lactone. These compounds had an inhibitory effect on the growth and development of L. decemlineata larvae. Especially strong effect on the feeding, growth and mortality of larvae showed farnesol.