Efficacy of fumigant compounds from essential oil of feverfew (Chrysanthemum parthenium L.) against maize weevil (Sitophilus zeamais Mots.): Fumigant toxicity test and in-silico study

Post-harvest insects are among the significant problems in the agricultural sector. The most accessible tools available for managing post-harvest arthropod-pests are fumigants because of the convenience of their applications and fast action in disinfecting. This study aimed to examine the fumigant toxicity of essential oil (EO) against maize weevil and identify the specific fumigants among the major components. The EO was extracted from aerial part of Chrysanthemum parthenium L. using Clevenger apparatus and was tested for fumigant toxicity. GC-MS was used to determine the chemical composition of EO. The major components were identified and screened virtually using Auto dock vina 1.2. in PyRx 0.8 platform. Dm AChE PDB ID: 6XYY was used as a target for molecular docking and malathion and pirimiphusmethyl were used as a reference for comparison. From the results of binding affinities, most of the major EO components showed better fumigant activity than the reference fumigants. More specifically 1,6-dioxaspiro[4,4]non-ene, b-farensen, bornyl-tiglate, g-terpinene, p-cymene, bornyl-acetate, bornyl-isovalerate, terpinen-4-ol, trans-chrysanthenyl-acetate and a-phellandrene were found to be effective fumigants against maize weevil. The above findings suggest that the EO of the aerial part of C. parthenium can be a potential candidate for the development of novel natural fumigants for stored products. KEY WORDS: Essential oil, Fumigants, Insecticides, Binding affinity, Maize weevil Bull. Chem. Soc. Ethiop. 2024, 38(2), 457-472.                                                               DOI: https://dx.doi.org/10.4314/bcse.v38i2.13