Biological control against the cowpea weevil (Callosobruchus chinensis L., Coleoptera: Bruchidae) using essential oils of some medicinal plants

摘要

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 thenutritional 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 temperatureand 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 oilof 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 pi 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 pi of Salvia and Scilla essential oils. The test on the seed germination using different essential oils, showed no damage to the germinatingseeds. The germination rate was 99%. These findings suggest that the tested plants can be used as a bio-insecticide for control of the C. chinensis pest of stored products.