Calidad nutricional del polen de colza (Brassica napus) y determinación de la flora apícola acompañante para las abejas melíferas

Rapeseed (Brassica napus L.), a winter oilseed, holds agricultural and apicultural significance due to its contribution of pollen and nectar at the end of winter. Pollination enhances crop yield and quality, as well as promotes uniformity in pod formation and maturation. It is crucial to understand the relationship between honeybees and rapeseed flowering. In a study conducted in Sauce, Canelones, and Arrayanes, Maldonado, the resources utilized by Apis mellifera L. from the crop to feed three randomly selected hives in each apiary were analyzed. Pollen and honey collected during flowering were investigated using palynological techniques. Precipitation during the crop cycle was considerably below the historical average. Key results include: a) In addition to rapeseed pollen, bees collected from eighteen additional plant species, in proportions higher than expected. b) Rapeseed pollen was a significant food source despite the water deficit. Hives showed variability in the timing of peak rapeseed utilization, indicating different preferences despite the same floral offer. c) Particularly, low levels of crude protein and ether extract were found, similar to those reported in semi-arid conditions. d) Mineral levels were low for magnesium but high for calcium, iron, and especially zinc, with values three times higher than reported. e) Honey from a single hive was predominantly rapeseed (>60%), with a significant contribution from perennial plants. f) No traces of glyphosate or AMPA were detected in samples taken 100 days after application. g) While no hive showed a prominent preference for rapeseed, differences were observed between hives and apiaries. h) Bees visit the crop more as flowering progresses and lipid content increases. i) Positive correlations were found between various quality parameters. The research highlights the importance of understanding bee feeding preferences to ensure the proper development of hives and anticipate contingencies due to climatic anomalies. Bees are recognized as valuable pollinators of rapeseed.