Ocorrência e impacto de polinizadores em girassol (helianthus anunus l.) na área urbana

Abstract

Sunflower (Helianthus annuus L.) is one of the most widely cultivated oilseed crops in the world because it supplies considerable sectors of the agricultural industry, such as biofuel production, crop succession and rotation, fodder, and food for humans. This crop depends considerably on pollinating agents, where 65% of the Brazilian crop production corresponds to pollination mediated by bees. Thus, the objective of this paper was to investigate and understand the role of pollinating bees in sunflower cultivation in an urban environment. The experiment was installed in a residence in the municipality of Erechim, Rio Grande do Sul, in October 2021, during the pandemic period caused by COVID 19. The sunflower cultivar used was Valentine, with two types of treatments containing 25 plants each: 1) free visitation of floral visitors and 2) exclusion of visitors. The treatment with free access to pollinating visitors demonstrated a significant contribution to sunflower pollination and reproduction. The other treatment, in which insects were excluded, had lower seed germination results than the free access treatment. The monitoring of spatial heterogeneity of bees in urban areas showed low frequency of visitation of Apis mellifera, as well as other species that are important for pollination. The results show the importance of pollination for the quality and productivity of the crop, contributing to an agriculture with better production and productivity results.