The antifeedant activity of lactones with di- and trimethylcyclohexane system was assessed in choice and no-choice bioassays against Leptinotarsa decemlineata and Alphitobius diaperinus larvae and beetles. The results showed that feeding deterrent activity depends on the structure of the tested compounds. Additional methyl group in the molecule of some compounds influences their activity increase or changes their properties from attractant to deterrent ones. The present results also demonstrate the species and developmental stage dependence of antifeedant activity.

The aim of the work was to study the feeding deterrent activity ofprecocenes, their synthetic analogues, and some related compunds to storage pests: Sitophi/us granarius L., Tribolium con/usum Duv., Trogoderma granarium Ev., and aphids: Myzuspersicae (Sulz.). Among all tested compounds precocenes I and 11 exhibited the best feeding deterrent activity against all tested insects. 4-Chromanols ( 16, 17 and I 8), alcohols 19, 20 and 3-chromanone (15) showed high deterrence towards the larvae of T con/usum. The best antifeedant activity towards the adults of both T confusum and S granarius was observed for substituted phenols with methoxy group at benzene ring. The biological tests carried out on aphids showed that the presence ofmethoxy group in the molecule was a crucial structural factor for the appearance of antifeedant activity against these insects.