Seleção e atratividade de plantas medicinais para vespas sociais em sistema ecológico de cultivo

Abstract

In ecological planting systems, the application of pesticides is not performed, thereby promoting the maintenance of beneficial soil organisms, pollinators, and natural enemies. These systems utilize intercropping, including medicinal plants. Such plants perform biological functions, such as attracting pollinators and defending them against herbivores, due to their production of secondary metabolites, which can modulate the metabolism of other plants and insects. Integrated management strategies include the use of attractive plants that interfere with foraging behavior and the conservation of natural enemies, such as social wasps. Diverse cultivation can increase biodiversity, reduce the incidence of herbivorous insects, and maintain ecological balance. The present study aimed to develop a methodology for selecting potentially attractive medicinal plants for natural enemies to be cultivated in intercropping systems within ecological planting, focusing on conservative biological control and evaluating the attractiveness of medicinal plants to social wasps in an ecological environment. Scoring criteria were established for the pre-selected plants, considering favorable aspects and unfavorable characteristics, with each species assigned a positive, negative, or neutral score. The preliminary selection of plants for evaluation was based on local biodiversity, edaphoclimatic conditions, availability of plant species, and the presence of favorable metabolites. The methodology was applied, and the selected species were planted in 2022 and 2023 at the Agroecology Sector of IFSULDEMINAS, within the Atlantic Forest biome, characterized by Seasonal Semideciduous Forest physiognomy. The experiment included six treatments chosen from twenty medicinal species based on a literature review: Clinopodium sp. (Clinopodium); Lippia alba (Brazilian Lemon Balm); Petroselinum crispum (Parsley); Bidens pilosa (Black Jack); Coriandrum sativum (Coriander); and Tagetes erecta (Marigold), arranged in randomized blocks. Insects were collected weekly for nine weeks using an entomological net and pan traps and identified based on specific literature. Rarefaction curves, species richness (bootstrap and species), abundance, similarity, and variance analyses were conducted. For species richness, B. pilosa and L. alba exhibited the highest averages, significantly different from T. erecta and Clinopodium sp., while the other plant species showed intermediate richness averages. Significant differences were also observed for abundance, with the highest value recorded for B. pilosa, significantly different from T. erecta and Clinopodium sp., while the other plant species presented intermediate abundance values. Therefore, B. pilosa and L. alba are promising species for providing alternative resources to natural enemies when present in intercropping systems in ecological cultivation environments. The developed methodology can be adapted for other locations and objectives, depending on market interests and the areas of action of farmers and researchers. With the necessary adjustments, the methodology proved to be effective, as the highest-scoring plants were also the most attractive in the field.