On a wing: the genetics and taxonomy of Vaccinium species from a pollination perspective.

摘要

Pollination of temperate Vaccinium species, including cultivated blueberry and cranberry, is largely mediated by bees. These pollinators have played a considerable role in the genetics and taxonomic status of Vaccinium species. In the blueberry section Cyanococcus, pollinators have been the facilitators of intra- and interspecific hybridization, and are responsible for the evolution of polyploidy and the diversity of polyploid species in this section. The occurrence of 2n pollen in all diploid blueberry species, and concordance with the frequency of 2n pollen-forming genotype frequencies in putative polyploid species evidences the pollinator's evolutionary contributions. Although non-random pollen dispersal has been reported, population genetic structure of both diploid blueberry and cranberry species is generally consistent with Hardy-Weinberg equilibrium expectations indicating panmictic pollination. This is especially notable in cranberry whose highly clonal and self-fertile nature would not promote a panmictic structure. Hybridization and introgression among syntopic diploid species and introgression from diploid to polypoid species in blueberry are also evident. The great intra-sectional taxonomic complexity that exists in Vaccinium is a function of a non-discriminatory pollinator.