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Chickpea (Cicer arietinum L.) is a valuable foodstuff but unfortunately this legume is prone to insect attacks from the chick pea weevil (Callosobruchus chinensis L.). This serious pest damages the chickpea and causes decreases in the yield and in the nutritional quality. Biological control is being used to deal with this problem. We tried different doses of the essential oils of three new medicinal plants, namely Salvia verbenaca L., Scilla maritima L., and Artemisia herba-alba Asso to limit the damage of the chick pea weevil pest, and to protect consumer’s health. To determine the effect and efficiency of the oil, the tests were conducted using the different biological parameters of fertility, longevity, and fecundity, under controlled temperature and relative humidity (28°C and 75%). The effectiveness of organic oils was demonstrated. We tested these oils on the germination of seeds. The obtained results showed that the tested plant oils have a real organic insecticide effect. The essential oil of Artemisia proved most effective as a biocide; achieving a mortality rate of 100%. A significant reduction in longevity was observed under the effect of 30 μl of S. maritima (1.3 days) and S. verbenaca (2.8, 4.6 days), respectively, for males and females compared to 8 and 15 days for the control. For fecundity, an inhibition of oviposition was obtained using 30 μl of Salvia and Scilla essential oils. The test on the seed germination using different essential oils, showed no damage to the germinating seeds. The germination rate was 99%. These findings suggest that the tested plants can be used as a bioinsecticide for control of the C. chinensis pest of stored products.

In order to find alternatives to chemical synthetic insecticides in the fight against pest of stored products, we evaluate the insecticidal and repellent activities of three essential oils by contact on the adults of R. dominica. Oils were extracted by hydrodistillation technique for 4 h using a Clevenger from the indigenous medicinal plants then the identification of the constituents was carried out on the basis of gas chromatography coupled with the GCMS spectrometry type Shimadzu TQ8030 coupled with a spectrometer. The different plants are S. molle, M. rotundifolia and S. calamintha. Our results of the contact-toxicity test of oils on substrate showed that the essential oil of M. rotundifolia has a highly significant insecticidal effect with a 100 % mortality at a concentration of 3 μL from the first h of treatment, Similarly the essential oil of S. calamintha has a highly significant biocidal effect with a 100 % mortality at a concentration of 5 μL even the first h of treatment also, the essential oil of S. molle that has an insecticidal effect with a mortality of 100 % at a concentration of 25 μL after 96 h of the treatment. The results of the study of the repulsive effect of the oils tested against the insect showed that the three essential oils possess a remarkable repelling effect just after 2 h of exposure with a PR (The percentage of repulsion) of 50 % for S. molle, 100 % for S. calamintha and M. rotundifolia. The toxicity test of dry powders against the adult beetle showed that the powders exerted their biocidal effect (1.2 g) with a mortality rate of 96, 90 and 75 % respectively for S. calamintha, M. rotundifolia and S. molle after 96 h of treatment. Biotechnological control through the use of essential oils extracted from these plants is tested as a bio insecticide has proved very effective in the protection of cereals against such insects that degrade quality and reduce yield and in addition threaten health of the consumer.

Stored products are among the most important foods in human nutrition. However; these products are under the pressure of many harmful organisms. One of these pests is Tribolium confusum Jacquelin du Val. (Coleoptera: Tenebrionidae). In this study, effects of two essential oils (Mentha rotundifolia and Satureja calamintha) and an enthomopathogenenic fungi on Tribolium confusum has been tried under the laboratory conditions, contact and repellent effects of essential oils and contact effect of dry plant extract were determined. As a result, essential oil, 3, 5, 10, 15 and 20 μl / ml doses of Mentha rotundifolia showed 100% effect after 24 hours, while Satureja calamintha reached 100% effect after 96 hours. 15 μl / ml dose of M. rotundifolia and 20 μl / ml dose of S. calamintha reached 100% detrimental effect after two hours. Powder doses of 0.6, 0.8 and 1.0 g of these plants, which were applied, caused the death of all the male and female individuals after 24 hours. In addition, the effects of 1x10 7 conidia / mL dose of the entomopathogenic fungus Beauveria bassiana after 24, 48 and 72 hours were 87.5%, 97.5% and 100%, respectively. It was seen that both essential oils and B. bassiana were successfully in suppressing the depot pest Tribolium confusum.

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