Insecticidal activity of some Asteraceae plant extracts against Tribolium confusum

摘要

Sixteen aromatic plant extracts from three species belonging to the Asteraceae family, were obtained by using organic solvents ofincreasing polarity. They were tested for insect growth inhibition, contact toxicity and antifeedant activity against adults and lar-vae of confused flour beetle Tribolium confusum du Val (Coleoptera Tenebrionidae). Discs made of wheat were incorporated witha single dose of 1% of different extracts. The antifeedant effect, larval growth inhibition and mortality were evaluated in multiple-choice tests. Responses varied with plant-derived material extract, stage of insect and exposure time. Larval growth inhibition wassignificantly induced by methanolic and ethyl acetate extracts of Mantisalca duriaei Briq. et Cavill. and petroleum ether, chloro-formic and methanolic extracts of Rhaponticum acaule DC. Antifeedant properties were detected in methanolic extracts of Mduriaei and R. acaule, petroleum ether and chloroformic extract of R. acaule and ethyl acetate extract of M duriaei. Scorzoneraundulata Vah1 seemed to be, however, attractive to the flour beetle. For all extracts, mortality was higher for larvae than adults. Itreached respectively 83%, 77% by using petroleum ether and methanol extracts of R. acaule. These results suggest that M duriaeiand R. acaule may be used in grain storage against insect pests.