Microsatellite-based genetic relationships in the genus Camellia: potential for improving cultivars.

There is a lack of published microsatellite data that characterizes Camellia spp. To address this, an initial study of sequence tagged microsatellite site (STMS) variation was undertaken with 132 accessions of Camellia spp., which included 24 accessions representing 22 different species or varieties as well as 63 cultivars of C. japonica, 33 cultivars of C. sasanqua, 7 cultivars of C. x vernalis, 3 cultivars of C. x hiemalis, and 2 cultivars of C. hybrida. The four primer sets used (MSCJAF37, MSCJAH46, MSCJAF25, and MSCJAH38) successfully amplified polymorphic alleles in all the species analysed, showing cross-transferability. Overall, 96 alleles were scored. MSCJAH38 primers produced the highest number of bands (30), while MSCJAH46 primers yielded the lowest number (15). The genetic distance between pairs of accessions was estimated on the basis of the Nei coefficient and a principal coordinate analysis was performed. The plot revealed a main differentiation between the C. japonica cultivars and the winter camellias. The distribution of the genetic variation, attributed by AMOVA, particularly highlighted genetic overlap among C. sasanqua cultivars and the cultivars belonging to C. x vernalis, C. x hiemalis, and C. hybrida. In conclusion, this study demonstrated that STMS markers offer a suitable method for detection of genetic variability and molecular study of camellia genotypes.