Effet insecticide des huiles essentielles sur la mineuse de pois chiche, Liriomyza cicerina R.

Quatre huiles essentielles obtenues par hydrodistillation à partir des plantes marocaines de la famille des myrtacées et lamiacées sont testées pour déterminer leur activité insecticide vis-à-vis des adultes et des larves de la mineuse de pois chiche (Liriomyza cicerina. R). La menthe pouliot, avec une dose de 33µl/l d’air a causé une mortalité de 100% sur les adultes et les larves, après trois heures et six heures d’exposition, respectivement. L’eucalyptus a montré une mortalité de 100% avec les doses de 33, et 83 µl/l, après six et trois heures d’exposition pour les adultes et les larves, respectivement. Puisque le test de l’activité insecticide de ces huiles essentielles par fumigation a montré des résultats prometteurs, il serait souhaitable d’étudier d’autres modes d’actions pour le contrôle de la mineuse sur la culture de pois chiche.

Chemical profiling of Artemisia herba-alba, Cuminum cyminum, Cinnamomum camphora, and Salvia rosmarinus essential oils and assessment of their insecticidal potential to control the wild cochineal Dactylopius opuntiae (Cockerell)

The wild cochineal, Dactylopius opuntiae (Hemiptera: Dactylopiidae), has become a serious pest of prickly pear Opuntia ficus-indica L. in the Mediterranean region. The present study investigated the insecticidal activity of four essential oils, namely Cuminum cyminum, Cinnamomum camphora, Artemisia herba-alba, and Salvia rosmarinus against D. opuntiae nymphs and adult females in laboratory and greenhouse bioassays. Laboratory tests showed that at a concentration of 2.5%, C. cyminum oil was the most effective (inducing 100% nymph mortality at 3 h after treatment), followed by C. camphora, A. herba-alba and S. rosmarinus oils which recorded comparable mortality rates ranging from 89.40 to 100%, while S. rosmarinus and C. cyminum oils induced the highest mortality rates on adult females (88% and 86%, respectively) 8 days after treatments. Under greenhouse con-ditions, the combined application of C. cyminum oil (2.5%) and black soap (10 g/L) showed the highest nymphs' mortality (100%) at 3 days after application. Adult female mortality in the greenhouse was lower than in the laboratory bioassay for all tested oils, with S. rosmarinus inducing 47% mortality at 2.5% at 14 days after the second spray. Eucalyptol was the main constituent of S. rosmarinus (41.20%) and C. camphora (56.47%) oils, and thujon-camphor was the major chemotype of A. herba-alba (30.55%/28.16%), while cuminaldehyde was the main compound of C. cyminum oil seeds (32.53%). These findings showed that the compounds of the two essential oils S. rosmarinus and C. camphora potential sources of insecticidal compounds and warrant further investigation

Insecticidal Activities of Atriplex halimus L., Salvia rosmarinus Spenn. and Cuminum cyminum L. against Dactylopius opuntiae (Cockerell) under Laboratory and Greenhouse Conditions.

The wild cochineal Dactylopius opuntiae (Hemiptera: Dactylopiidae) is one of the major insect pests of the prickly pear Opuntia ficus-indica (L.) in Morocco, a well-known fruit and vegetable crop of arid and semi-arid regions around the world. The present study investigated the insecticidal potential of six extracts (three aqueous and three hydroalcoholic (MeOH/H2O, 20/80 (v/v)) from Atriplex halimus (leaves), Salvia rosmarinus (leaves) and Cuminum cyminum (seeds) to control nymphs and adult females of D. opuntiae under laboratory and greenhouse conditions. Out of the tested samples, A. halimus aqueous extract showed the highest activity, inducing mortality rates of 67.04% (after 4 days) and 85% (after 8 days) on nymphs and adult females of D. opuntiae, respectively, at a concentration of 5% under laboratory conditions. It also showed the highest mortality rate of nymphs with 100% (4 days after application) and 83.75% of adult females (7 days after the second application) at a concentration of 5% when combined with black soap at 10 g/L under greenhouse conditions. The difference in the toxicity of plant species of the study was correlated with their saponin content. A total of 36 of these triterpene glucosides were suggested after a comprehensive LC-MSn profiling of the most active extract, A. halimus, in addition to phytoecdysones and glycosylated phenolic acids and flavonoids. These findings provided evidence that the aqueous leaf extract of A. halimus could be incorporated in the management of the wild cochineal as an alternative to chemical insecticide