Forrajeo de abejas sobre cultivos de soja, una aproximación mediante análisis de cargas corbiculares en Apis mellifera

Abstract

The interactions between plant species and their pollinators are transcendent in the field of biology and also acquire singular importance in their agro-productive dimension; both for crops that demand pollination services and for those that require phytosanitary applications during their flowering, especially if from these flowers bees extract pollen, given that this product (source of protein from bees) generally registers greater chemical contamination than the nectar. Consequently, it is useful to know and eventually predict the foraging behavior of bees on soybean cultivation, given their majority participation in the Argentine agro-productive matrix. A novel methodological approach is proposed that consists of capturing bees during entry to the hives with entomological nets and subsequent palynological analysis of their corbicular loads (the percentage contribution of soybeans was weighted, concerning to other resources, with the number of bees trapped in each repetition). The captures were made sequentially in hives bordering a batch of soybeans during its flowering period, every 2 days and at 6 times (9:00, 10:30, 12:00, 13:30, 15:00 and 16:30 h), performing 3 repetitions per schedule. The results indicate that the bees prefer to forage soybean pollen at times between 12:00 AM and 15:00 PM with a maximum of collecting activity around 13:30 PM (p < 0.001). It also highlights a progressive increase in the preference for soybean pollen as the crop progresses, registering maximum values after its full bloom (p < 0.001). The results are multifactorially conditioned by the floral offer of the crop, the simultaneity of other alternative blooms and by meteorological conditions.