Contribution of insect pollination to Macadamia integrifolia, Coffea arabica, and Dimocarpus longan in Hawaiʻi

Abstract

The contribution of insect pollination was assessed for three crops in Hawaii: Macadamia integrifolia, Coffea arabica, and Dimocarpus longan. These three plants, having very different mating systems, were shown to be visited by a range of insects in the Orders Hymenoptera, Diptera, Lepidoptera, and Coleoptera. While Diptera ranked highest in species richness, Apis mellifera, the honeybee, was the most abundant insect visiting the flowers in all three study orchards. Overall fruit set and fruit retained was increased with insect pollination, as well as fruit quality. Abundance, combined with foraging behavior and stigma contact suggested that honeybees were the greatest contributors to pollination for these crops.