Pollen Production and Nutrient Composition in Two Northern Highbush Blueberry Cultivars: Implications for Pollinator Nutrition

Specialty crops like blueberries depend heavily on pollinators, particularly bees, for enhanced fruit set and optimized yield. The Northern highbush blueberry, widely cultivated in the Pacific Northwest of the United States, includes several key cultivars such as 'Duke' and 'Elliott'. Given that pollination efficiency is directly linked to the availability and quality of pollen, understanding the pollen production of these cultivars is critical for optimizing pollination strategies and maximizing fruit yield throughout the growing season. Additionally, as bees depend on floral resources like nectar and pollen for their nutrition, the nutritional quality of pollen from these blueberry cultivars plays a key role in supporting healthy bee populations. This study compares key pollen parameters, including production and nutritional quality, between the 'Duke' and 'Elliott' cultivars. 'Elliott' produced nearly twice the amount of pollen per flower by weight compared to 'Duke'. Both cultivars showed relatively low pollen protein content and comparable pollen lipid levels. The analysis of phytosterol composition revealed significant differences between the cultivars. This study contributes to a more detailed understanding on the quantitative and qualitative differences in pollen, and ultimately provides insights that can inform cultivation practices and enhance overall blueberry production.