Colorimetric characterization of the Pollen Flora Collected by Apis mellifera L. in the Laguna Oca and Herraduras from the Paraguay River Biosphere Reserve, Formosa (Argentina)

The aim of this study is to know the pollen flora collected by Apis mellifera L., from an apiary located in the Laguna Oca and Herraduras from the Paraguay River Biosphere Reserve in Formosa, Argentina. The field work consisted of monthly monitoring of the phonological flowering stages of the species near the apiary, during the spring of 2020 and the summer-autumn of 2021. The pollen loads were classified by color considering the Munsell Code and processed according to the acetolysis technique. Nine samples were obtained, which were subdivided into 24 subsamples by color, resulting in 19 monofloral load, which varied between the ranges of yellow, orange, red, and brown. Monofloral pollen loads were identified of native tree, shrub, and herb species. The bee foraging behavior was observed in the diversity of the species collected in the monofloral loads during the spring, whereas three bifloral loads and a two multifloral loads were observed in summer and autumn. In the most of the pollen loads color and the botanical origin was determined and was observed that the color of monofloral pollen varies with the percentage and type of accompanying flora.