Ethnobotanical and phytochemical insights into native and naturalized plants for cashew pest control in Guinea-Bissau

Essential oils are increasingly recognized as ecofriendly alternatives to synthetic pesticides, especially in tropical regions with high pest pressure and limited crop protection resources. This study evaluates native and naturalized plants in Guinea-Bissau— Ageratum conyzoides , Azadirachta indica , Chromolaena odorata , Cymbopogon giganteus , and Mesosphaerum suaveolens —for sustainable pest management, combining ethnobotanical documentation, essential oils characterization, and existing bioactivity data focused on cashew pests. An African-wide ethnobotanical assessment using Plant Resources of Tropical Africa (PROTA) and Scopus databases revealed that these species were predominantly used for medicinal and pest-related applications, most frequently reported in West Africa. Essential oils were extracted from leaves by hydrodistillation and chemically characterized using gas chromatography coupled with flame ionization detection and mass spectrometry. Essential oils yields varied among species; C. odorata and C. giganteus yielded the highest. Chemical profiling revealed species-specific compositions dominated by chromenes, monoterpene hydrocarbons, and sesquiterpene hydrocarbons. Major constituents included precocene I, limonene, sabinene, β-caryophyllene, and 1,8-cineole, compounds widely reported for their insecticidal, repellent, and antifeedant properties, indicating their potential for sustainable management of cashew pests in West Africa. By combining ethnobotanical knowledge with phytochemical characterization, this study highlights the untapped potential of locally available plant-derived essential oils, rooted in traditional practices, as potentially valuable resources for sustainable agriculture.