Genetic Diversity and Population Structure of Prunus umbellata Elliot in Florida

The Prunus L. genus belongs to the subfamily Amygdaloideae (=Prunoideae) of the Rosaceae family. It is distributed around the world, with approximately 200 species. Species native to southeastern United States include P. americana Marsh., P. angustifolia Marsh., P. geniculata Harper, and P. umbellata Elliot. The existence of several wild plum species in Florida creates a unique opportunity for the study of allelic variation associated with important economic traits that can then be targeted and rapidly transferred to domesticated plum using molecular markers. The main objective of this research is to analyze the genetic diversity and population structure of P. umbellata in Florida. A total of ~70 genotypes of P. umbellata ranging from North to South Florida were fingerprinted using 41 SSRs distributed across the peach genome (~15–25 cM). Number of alleles per locus (A), effective number of alleles (Ae), observed heterozygosity (Ho), expected heterozygosity (He), Wright’s fixation index (F), polymorphism information content (PIC), and Nei’s genetic distance (GD) per locus were calculated. An unrooted Neighbor–Joining tree was constructed using Nei’s genetic distance. Population structure was analyzed.  Prunus umbellata represents an underutilized resource for association genetic studies of adaptive and commercial traits in plums.