Effet biologique des extraits bruts de Datura stramonium.L.,1753 sur quelques insectes nuisibles dans la région de Ghardaïa.

Abstract

This study is based on the toxic biological effect of the extracts of Datura stramonium on the drosophila fly and the Culex pipiens mosquitoes from the Beni-isguen wilaya of Ghardaïa. The extracts of D.stramonium plant leaves and seeds is obtained by maceration. The tests of biological effect are performed on different doses of Datura Stramonium extract, the treatment is carried in vivo, by ingestion which makes it possible to determine the various physiological parameters such as the mortality rate, the lethal time 50 (TL50) and lethal dose 50 (LD50) and biochemical parameters determine the amount of lipids ,the amount of carbohydrate and the amount of protein. In vivo treatment reveals a percentage of deaths that increase as function of the concentration or mortality of the D.melanogaster adult after 32 h of the lots treated with the seed extract compared with C.pipiens .The mortality recorded rate after 69 h with the same seed extract . However, the treatment of D.melanogaster and Culex pipiens by different doses of Datura stramonium extract shows a significant reduction in different levels of primary metabolic levels of adult of D.melanogaster such as the dose level of lipid-treated by the leaf extract is0.108±0.113 mg / ml and the dose of 100 is 0.023±0.024 mg / ml as it indicates a low fat level. Also, the treatment of Culex pipiens by the extract of seeds and leaves. The result shows a decrease in the rate of carbohydrates at dose of 100% by 480±118 µ g / ml compared to individuals treated with a leaf extract of 859.17±0 µ g / ml The results obtained reveal the mortality studied of both insects , indicating that the plant has insecticidal properties and it reflects by the effect of extracts on the levels of metabolism .