Development of SSR markers to study diversity in the genus Cymbidium

Cymbidium spp. are important potted flowers with extremely high ornamental and economic value. The present study reports the development of 14 new simple sequence repeat (SSR) markers through the construction of an enriched Cymbidium goeringii library and cross-amplification in Cymbidium sinensis and Cymbidium hybridium. Of 525, 322 (61.33%) clones had SSR motifs and among motifs di-nucleotides were predominant and followed by tri-nucleotide and tetra-nucleotide type. In polymorphic analysis using 14 newly developed SSRs, a total of 201 alleles across 96 Cymbidium accessions were detected with an average of 14.4 per locus. The average heterozygosity was 0.394. The average gene diversity and polymorphism information content values were 0.394 and 0.639, respectively. The mean genetic similarity coefficient was 0.4297, indicating a wide genetic variation among the Cymbidium accessions. These newly developed SSRs will be useful tools for genotype identification, germplasm conservation, molecular breeding, and assessments of genetic diversity and population structure in Cymbidium.