Poster

         Hybrids and Hybridization

Evaluating genetic intermediacy of a naturally occurring hybrid blueberry, Vaccinium x marianum

Presenting Author
Laura George
Description
Hybridization is common in plants and is a mechanism for increasing plant biodiversity and vigor. Detecting hybrids in nature can be accomplished by genetic data. The basis of this research is to evaluate if the highbush blueberry, Vaccinium x marianum, is a hybrid between the parental species, Vaccinium fuscatum and Vaccinium formosum. Morphological data suggests V. x marianum has traits intermediate to the parental species, and this research project used genetic data to evaluate differences between the parents that are expected in V. x marianum if it is a hybrid. Leaf samples of the three forms were collected from four locations in Virginia. They were identified in the field using a diagnostic key. Fourteen microsatellite loci were selected to test with the samples. Data from seven loci were evaluated for this study, although one locus was not found to be consistently scorable and thus was removed prior to analysis. Our preliminary analysis suggests that Vaccinium x marianum is genetically intermediate to the parental species. The parental species are genetically distinguishable from one another and little evidence of introgression was found in these samples. Samples of V. x marianum show extensive variation among samples, suggesting that it may represent multiple hybrid generations and diverse origins. More work is needed to examine the genetic variation of the three forms, and this semester I will use chloroplast markers to evaluate the maternal origin(s) of V. x marianum. Hybridization between blueberry species is common in nature and studying hybrids can further the understanding of genetic diversity, adaptation, and  evolution of blueberries species.