Grain-protective properties of herbal extracts against the bean weevil Acanthoscelides obtectus Say

Abstract

Studies were conducted to evaluate the effect of the ethanol extracts from five aromatic medicinal plants against the bean weevil, Acanthoscelides obtectus (Coleoptera: Curculionidae). The extracts were tested for potential to protect stored legume seeds in terms of their repellency, toxicity and reduction of F1 progeny. Significant insecticidal activity was exhibited only by the 100% concentrated extracts from Urtica dioica L. and Taraxacum officinale L., whereas both 100 and 30% extracts from these plants were effective in repellency and reduction of F1 progeny. Although the extract form Achillea millefolium L. (100%) was ineffective in insecticidal activity, it provided a good level of repellency and reduction of F1 progeny. Extracts from Sambucus nigra L. and Juglans regia L. were ineffective in all conducted bioassays.