PHYTOCHEMICAL STUDY AND BIOINSECTICIDAL EFFECT OF THE CRUDE ETHONOLIC EXTRACT OF THE ALGERIAN PLANT ARTEMISIA JUDAICA L. (ASTERACEAE) AGAINST THE BLACK BEAN APHID, APHIS FABAE SCOP.

Plants are the nature's biochemical factories.They bio-synthesize a diverse array of different natural products, such as alkaloids, terpenes and terpenoids, phenolic compounds, flavonoids and coumarins through their structural mechanisms to reduce insect attacks, both constitutive and inducible, while insects have evolved strategies to overcome these plant defenses.There is a widespread effort to find new pesticides, and currently it is focused on natural compounds such as flavonoids, coumarins, terpenoids, and phenolics from diverse botanical families from arid and semi-arid lands.Algeria by the diversity of its habitats has a very diverse flora.Some of these plants have very interesting insecticidal properties.The aim of this study is to evaluate the insecticidal effect of the plant Artemisia judaica L. (Asteraceae).The crude ethanol extract of the plant A. judaica was tested on the black bean aphid Aphis fabae Scop.Four doses (12.5, 6.25, 3.12 and 1.56 mg mL -1 ) were tested on contact wingless adults.The results have showed that the tested extract has been very powerful to aphids.At the highest dose 12.5 mgmL -1 , the 100% of mortality were recorded 2 hours after treatment, and for the lowest dose (1.56 mgmL -1 ) it was after 96 hours.The LD50 calculated 2 hours after treatment from the regression lines Probit = ƒ (doses) shows that it is 2.75 mgmL -1 .This powerful insecticidal activity of the tested crude extract could be due to the richness of the plant on phenolics compounds known for their bio-insecticide action.