Analysis of genetic relationships and identification of flowering-mei cultivars using EST-SSR markers developed from apricot and fruiting-mei

Sixteen pairs of EST-SSR primers developed from apricot (Prunus armeniaca L) and 11 pairs from fruiting-mei (Prunus mume) were employed in PCR amplification for analysis of genetic relationships and identification of 54 flowering-mei accessions. The results show that 14 pairs of apricot and 11 pairs of fruiting-mei EST-SSR primers had clear amplification products in flowering-mei, among which 8 apricot and 9 fruiting-mei EST-SSR primer pairs could amplify polymorphic bands and a total of 65 alleles, were detected from all the 54 flowering-mei accessions. The ratio of polymorphic bands amplified by the 8 apricot and 9 fruiting-mei EST-SSR primers 59.1% and 72.1%, respectively, indicating that the levels of polymorphism from fruiting-mei EST-SSR primers were relatively high. Analysis of genetic relationships of all the 54 accessions by the polymorphic SSR markers showed that EST-SSR markers could clearly separate flowering-mei accessions and the clustering pattern of most cultivars was in accordance with their pedigree information. In addition, a manual cultivar identification diagram (MCID) of the 54 cultivars was constructed using polymorphic bands from the DNA fingerprints. To the best of our knowledge, this new strategy is by far the most efficient and workable in identifying plant varieties using EST-SSR markers. This MCID strategy could separate all the cultivars from each other, with the polymorphic bands employed for identifying the cultivars and the corresponding primers being marked in the correct position on the MCID. This flowering-mei MCID can provide the information needed to separate any of the 54 important cultivars studied here, which is of benefit to flowering-mei cultivar identification for cultivar-right-protection and the general flowering-mei industry in China.

► The genetic relationship of 54 flowering-mei (Prunus mume) cultivars was studied using EST-SSRs.
► All the EST-SSRs were developed both from apricot and mei.
► The transferability of apricot EST-SSR primers in mei was also first analyzed.
► The polymorphic bands from eight primers could separate 48 out of the 52 cultivars.
► A manual cultivar identification diagram (MCID) of the cultivars was first generated.