Atividade inseticida, fagoinibidora e repelente de extratos e frações de Solanum paniculatum sobre Sitophilus zeamais (coleoptera: curculionidae)

Abstract

Post-harvest losses caused by insect pests represent one of the main factors responsible for the reduction in the quality and quantity of stored grains, with the maize weevil, Sitophilus zeamais, standing out as one of the species of greatest economic importance. In this context, the present study aimed to evaluate the bioinsecticidal potential of extracts and fractions obtained from the leaves of Solanum paniculatum in the control of S. zeamais. The plant extracts were obtained through an extraction process and subsequently fractionated using solvents of different polarities, being evaluated through laboratory bioassays of mortality and insecticidal activity. Additionally, qualitative phytochemical and chromatographic analyses were performed to identify the main secondary metabolites present. The results demonstrated high bioinsecticidal activity of the tested extracts and fractions, with emphasis on the crude extract and the acetate organic fraction, which showed high insect mortality rates. Chemical analyses indicated the presence of phenolic compounds, flavonoids, and lipophilic substances, metabolites frequently associated with insecticidal activity. Therefore, it is concluded that Solanum paniculatum presents promising potential as a source of natural compounds for the development of bioinsecticides applicable to the sustainable management of stored-grain pests.