Metabolomic Approaches in Assessing the Insecticidal Activity of the Extracts from Argemone ochroleuca Sweet (Papaveraceae) Against Three Diverse Crop Pests of Economic Importance.

For years, crop protection from pest attack, has been dominated by the use of synthetic insecticides. However, many of them can cause severe environmental problems and human health. In this context, the use of plant extracts constitutes an alternative to avoid this kind of contaminants. In this work, we investigated the chemical constituents and insecticidal activity of different extracts of leaves and stems of Argemone ochroleuca Sweet (Papaveraceae) against three economically important pests Sitophilos zeamais (Coleoptera:Curculionidae), Galleria mellonella (Lepidoptera:Pyralidae) and Xyleborus ferrugineus (Coleoptera:Scolytidae). A GC-MS analysis mostly revealed the presence benzylisoquinoline alkaloids such as allocryptopine, protopine, among others. For the insecticidal activity, after nine hours of contact, the methanolic leaves extract showed a 100 % of mortality, followed by the dichloromethane stems extract with up to 93 % of mortality. The results suggest that the benzylisoquinoline alkaloids are involved in the insecticidal activity through the octopaminergic system of the tested insects.