Evaluation of Datura metel Leaves Extracts for their Antioxidant and Nematicidal Properties against Meloidogyne javanica as a Potential Biopesticide

Meeting the food needs of the world's population has become a major challenge for all countries. The availability of this food depends on a number of factors, including good crop management. The latter is under attack from several plant parasites, including root-knot nematodes, which are sometimes responsible for more than 30% of crop losses. In this study, we evaluate the nematicidal properties of Datura metel leaf extracts. In this study, secondary metabolites were extracted using solvents of different polarity and phytochemical characterization was carried out using qualitative determination methods. The nematicidal activity of the extracts was evaluated on Meloidogyne javanica nematodes at the J2 stage of larval development. The results showed the presence of alkaloids, flavonoids, tannins, reducing compounds and saponins in Datura metel leaves. All extracts caused varying degrees of mortality depending on their type, concentration and incubation time. Polar extracts were the most active in the in vitro study, with 77, 85 and 99% mortality after 48 hours of incubation for crude, aqueous and ethyl acetate extracts respectively. However, in the in vivo study, the polar aqueous extract remained the most active with a mortality rate of 63%. This was followed by the non-polar hexane extract with 61% mortality. The differences and variations observed in these results could be explained by the nature of the compounds present and their synergistic and antagonistic effects. From these results it can be concluded that the Datura metel plant could be a promising alternative to synthetic pesticides for the control of plant parasites.