Bee Pollination Highly Improves Oil Quality in Sunflower

Sunflower is a pollinator-dependent crop and one of the most cultivated oilseeds in the world, supporting important sectors of the agricultural industry, such as the food supply, because it is an important source of vitamin E and unsaturated fatty acids for human health. Although it is well stablished that bee pollination improves sunflower seed set, it is still unknown if pollinators influence the nutritional composition. Considering the economic importance of sunflowers for several Brazilian agricultural sectors, the aim of this study was to evaluate the effect of the bee community for (1) achene quality (weight and nutritional composition) and (2) market value. Exclusion experiments were performed with hybrid sunflowers and showed that bee pollination enhanced the achene weight by 91 %, the levels of vitamin E by 45 % and unsaturated fatty acids by 0.3 %. Also, it was estimated that due to the pollination services provided by bees, the grower of the sunflower cultivar used in this study nearly duplicates the sale value of the achenes per hectare of cultivated area. Thus, the current study highlights the importance of bees as providers of cross- and self-pollination to nutritional quality of sunflower achenes and provides useful baseline figures to further evaluations of the effects of pollinators on human diets and health.