The Influence of Industrial Hemp (Cannabis sativa L.) Pollen Composition to Bee Preference

Apart from its economic value, industrial hemp ( Cannabis sativa L.) is a prolific-pollen producer serving asfood source for bees. However, little is known if varietal differences in hemp pollen chemistry wouldinfluence bee preference. Here we present the chemical profile of pollen from four industrial hemp varieties(Canda, CFX-2, Henola, and Joey) and bee abundance and diversity among the four varieties. From directvisual counts and pan traps, the number and type of bees on each hemp variety was recorded. In addition, thechemical composition (proximate analysis and profiles of mineral and amino fatty acids) of pollen from eachhemp variety was analyzed. Three bee types (bumble bees, honey bees and sweat bees) were recorded for atotal of 1,826 during the entire sampling period . Among these bees, sweat bees and bumble bees were the mostprevalent and were highest on Joey variety. The four hemp varieties expressed protein content ranging from6.05% to 6.89% and highest in Henola. Seventeen amino acids were expressed in all varieties, among whichleucine recorded the highest content ranging from 4.00 mg/g in Canda to 4.54 mg/g in Henola. Overall, Henola expressed high protein, amino acid, saturated and monosaturated fatty acid contents and recordedsignificantly fewer bees compared to Joey with low content of these components except having high contentof polyunsaturated fatty acids. Our findings suggest that hemp pollen would promote bee health andsustainability of pollination system.