Insecticidal effect of three species of eucalyptus hexane extracts (Eucalyptus microtheca, E. globules, and E. camaldulensis) on larvae of Sawtoothed grain beetle, Oryzaephilus surinamensis L. (Coleoptera: Silvanidae)

Due to the health problems resulting from the use of synthetic pesticide on stored products, using plantwith insecticidal properties could be considered as an effective and safe method to pest control. TheEucalyptus plant as a potential plant can be studied for this purpose. This experiment was conducted toinvestigate the insecticidal effects of three species eucalyptus hexane extract (Eucalyptus globules,E.microtheca, E.camaldulensis) on larval stage (8-10 after appearance) of Sawtoothed grain beetle,Oryzaphilus surinamensis. In this test, different concentrations of Eucalyptus were used for toxicityevaluation. So using a micropipette, the different doses of extracts were added to filter paper and larvae wereexposed to toxic fumigant. Hexane solvent was used for control. 15 Larvae were exposed to eucalyptusextract for 24 hours under laboratory conditions 28±10C, 65±5% RH. LC50 values of three Eucalyptuseshexane extract (E. microtheca, E. globules, E. camaldulensis) were estimated 2078, 2172, 2229 μl/lairrespectively. According to values calculated, the larval stage was sensitive to extracts of eucalyptus hexaneand 3 spices of eucalyptus didn‟t have significant differences.

کلیدواژه ها:

Insecticidal effect ، Sawtoothed grain beetle ، Eucalyptus