The 2012 ASHS Annual Conference

North America is a center of diversity for Prunus species. Tree architecture, endodormancy requirement, heat requirement, fruit development period, fruit size, fruit texture, fruit flesh, disease resistance, and adaptive changes to multiple environmental conditions, are a few examples of the tremendous genetic variability available in the plum germplasm. Wild native Prunus species constitutes an important source for genetic diversity for stone fruit breeding and selection. The study of genetic variability within the subgenus Prunus section Prunocerasus was the primary objective of this research. In addition, the transferability and polymorphism level of 41 simple sequence repeat (SSR) markers distributed across the peach genome (~15–25 cM) in section Prunocerasus was studied. A total of 11 North American plum species were used to determine the genetic diversity available in section Prunocerasus. One genotype per species for: P. americana Marsh., P. angustifolia Marsh., P. geniculata Harper, P. hortulana L.H. Bailey, P. maritima Marsh., P. mexicana S. Watson, P. munsoniana W. Wight & Hedrick, P. persica (L.) Batsch cv. Okinawa, P. pumila L., P. umbellata Elliot, and P. fasciculata (Torr.) A. Gray (outgroup) were used for the preliminary screen. The 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. A rooted Neighbor-Joining tree was constructed using Nei’s genetic distance. An average of 10.7 A, 0.58 Ho, 0.31 F, and 0.82 PIC were observed. The peach SSR markers were found to be widely transferable and applicable to the study of wild Prunus species genetic diversity.