Submitted to: Iowa Academy of Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 2, 1999
Publication Date: N/A
Interpretive Summary: Honey bees have been the traditional pollinator for sunflowers in field cages at the USDA-ARS North Central Regional Plant Introduction Station located in Ames, IA. It is time consuming and expensive to maintain large numbers of honey bee hives. This research tested for alternative pollinators that might replace honey bees for pollination of sunflower in field cages. Honey bees were compared to bumblebees and mason bees to see which is the most efficient for seed production in field cages. When data were combined from two years, honey bees produced significantly more seed per plant than did the other bees tested. The impact (value) of this research is that we have eliminated two bee species as potential pollinators of sunflower for our germplasm seed-increase field plots. We will continue to use honey bees for pollinating wild type sunflowers in field cages.
Technical Abstract: Honey bees, Apis mellifera, have been used for several years to control-pollinate many plant species maintained at the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS) located in Ames, Iowa (USA). Because maintaining large numbers of honey bees is quite expensive and time consuming, we began looking, in 1995, for substitute bees that can be easily managed and would be less expensive to maintain. One such bee we tested was the hornfaced bee, Osmia cornifrons, a solitary bee imported from Japan in the late 1970s. We also tested a mixture of native bumblebees, Bombus bimaculatus and B. impatiens, which are important natural pollinators found in the Midwest. These bee species were compared in field cages to determine which would produce the greatest number of seed/plant on the wild annual sunflower, Helianthus petiolaris. When test data were combined from 2 years, honey bees produced significantly more seed/plant than did O. cornifrons.