Influência de inseticidas na fauna de visitantes florais em diferentes culturas agrícolas

Abstract

Pollinating is one of the most important environmental services inside an ecosystem. Many times, in order for this service to be performed, the plant needs animals, the pollinators, in order to efficiently transfer the pollen grains. However, the pollinators are submitted to the influence of many factors in the environment in which they live, which may contribute or impair this activity. Thus, the phytosanitary products may negatively influence the attractiveness or the behavior of the floral visitors, or even not influence this activity at all. The present work aimed at evaluating the influence in the frequency of floral visitation and the composition of the floral visitors’ fauna in bell pepper and tomato plant from a previous application of phytosanitary products in these cultures. The applied products were cyantraniliprole, cyantraniliprole + thiamethoxam, thiamethoxam, imidacloprid, cyantraniliprole + abamectin and diafenthiuron. The trials were performed next to the Estação Experimental da Agroteste, in Lavras, Minas Gerais, Brazil, in the period of June to November of 2012. The total number of visits to the flowers and the number of flower visiting species present in the experiments performed in the different cultures were measured. A survey was also performed of the flower visitors of the spontaneous plants found in the experimental area for comparison of the flower visiting fauna of the experiments. The phytosanitary products applied in the experiments of the tomato plant culture as well as in the experiments of the bell pepper culture did not influence the insect visiting frequency, suggesting a possible selectivity of the chemical molecules used in the period in which the experiments were evaluated. We also observed a similarity in the composition of the flower visiting fauna of the two cultures with the evaluated spontaneous plants. Thus, the results suggest that the products used may be employed in an integrated pest management program in the tomato plant culture and in the bell pepper culture, without impairing the attractiveness of potential pollinizers.