1Wroclaw University of Environmental and Life Sciences, Department of Chemistry.
Nicolaus Copernicus University, Department of Invertebrate Zoology, Gagarina 9, 87–100 Toruń, Poland.
*Correspondence author, E. Mail: mszczep@umk.pl.
The insecticidal activity of star anise (Illicum verum Hook. F.) fruits extracts was determined against the lesser mealworm (Alphitobius diaperinus Panzer). In laboratory tests, 25.0, 12.5, 6.25 and 3.12 mg/ml−1 extract concentrations as acetone solutions were added to diet of larvae and adults. The antifeedant effects of extract were investigated using choice and no-choice tests. The most sensitive stage was 7 days old larvae followed by 14 days old. Thirty days old larvae were highly tolerant to test extract. All applied doses caused the 100% mortality of younger larvae, however, only higher concentrations (25.0 and 12.5 mg/ml−1) were toxic to older larvae, whereas 25.0 mg/ml−1 dose caused no mortality in adults. At lower doses, some older larvae developed into pupae and adults, but their body weight was lower than control. The extract was a very good feeding deterrent against larvae, but only in choice test. In the no choice test, the antifeedant effect was very weak.
Allelochemicals, Alphitobius diaperinus, antifeedants, essential oils, Illicum verum, lesser mealworm, star anise fruits
