Chemical control using synthetic products against pests of stored foods converted with restrictions such as the toxicity of living things and ecological risks. Today the world opinion is oriented towards a new fight against pests, among the alternative strategy, the use of natural insecticides of plant origin. This work aims to evaluate the insecticide effect of essential oils of Rosmarinus eriocalyx leaves against a wheat pest stored Sitophilus granarius and the evaluation of their antioxidant activity in vitro. The insecticide activity of essential oils of this plant was assessed by the filter paper contact test method and the repulsion test by the method of preference and determination of lethal doses DL50 and DL90, and the percentage of repulsion, measurement of anti-radical activity by trapping free radical DPPH and determining EC50. With regard to the chemical composition of the volatile oils of R. eriocalyx, 1.8-cineol (48.47%), camphor (17.04%), 'pinene' (7.58%), 'pinene' (6.99%) were the main compounds, the results showed that the essential oil of the R.eriocalyx leaves has a very high rate of repulsion PR= 96.25% at the dose of 20 µl/ml after 120 minutes of exposure, the mortality rates of the wheat weevil in the toxicity tests have increased with increased doses and over time. lethal doses for the dose 20 µl/ml has 50% DL50 = 0.306 µl/cm2 and 90% DL90 = 2.513 µl/cm2 for 72 hours of exposure, , in the test system DPPH one determines the trapping activity of radical free of essential oil 23.794% ± 2.908% EC50 = 8.585 ± 2,608 mg/ml. The activity of synthetic antioxidants of gallic acid, quercetin and ascorbic acid were also determined in parallel experiments as positive control. The essential oils of R.eriocalyx leaves can be used as a natural alternative to synthetic insecticides to control pests of stored foodstuffs.
Author Biographies
Reguig M’hamed dit Salah Dine, Laboratory of Water Resources and Environment, University of Saida, Algeria
Laboratory of Water Resources and Environment, University of Saida, Algeria
Labani Abdelrahamene, Laboratory of Water Resources and Environment, University of Saida, Algeria
Laboratory of Water Resources and Environment, University of Saida, Algeria
Terres Mohamed, Laboratory of Water Resources and Environment, University of Saida, Algeria
Laboratory of Water Resources and Environment, University of Saida, Algeria
Mellal Tahar, Laboratory of Water Resources and Environment, University of Saida, Algeria
Laboratory of Water Resources and Environment, University of Saida, Algeria