DNA Fingerprinting and Genetic Diversity Analysis with Simple Sequence Repeat Markers of 217 Potato Cultivars (Solanum tuberosum L.) in China

Since 1950, more than 620 potato cultivars have been released from Chinese breeding programs, some of which have similar genetic background and phenotype. In this study, 16 parental cultivars widely used in breeding were used to screen 138 simple sequence repeat (SSR) markers. Out of 138 SSR markers, 20 were polymorphic that were used to analyze the genetic diversity of 217 potato cultivars grown in China. In total, 249 alleles were detected with these 20 markers and 244 of them (97.99%) showed polymorphism. The number of alleles ranged from 7 to 22 with an average of 12.45 alleles per primer and polymorphic information content (PIC) ranged from 0.64-0.93 with an average of 0.83. Fragment sizes varied from 80 to 380bp. Based on PIC values and the clarity of PCR amplification bands, 11 SSR markers were selected and able to differentiate all of the 217 cultivars. The estimated similarity using these polymorphic SSR markers between the cultivars ranged from 0.63 to 0.99, indicating a narrow genetic base. Fingerprinting and genetic diversity analysis in this study provides useful information for the protection of intellectual property, as well as the exploration and utilization of these potato cultivars.