Development of microsatellites and genetic diversity analysis of Scutellaria baicalensis Georgi using genomic-SSR markers / 药学学报

ABSTRACT

A total of 12 775 SSRs were identified from Scutellaria baicalensis Georgi genomic database, accounting for 2.56% of the total genomic sequences. The result showed that S. baicalensis SSRs were based on 68.32% dinucleotide and 18.63% trinucleotide repeats; CT/GA and TTC/GAA were predominant in the dinucleotide motifs and the trinucleotide motifs respectively. Nine primers were selected to produce highly reproducible SSR bands and were used in studying the genetic diversity of S. baicalensis, 50 individuals from ten populations. 68 SSR polymorphic loci were detected, these loci were polymorphic and displayed 4 to 12 alleles per locus with a mean number of 7; the effect number of alleles was 3. Expected heterozygosities were 0.6 and were far more greater than the average in dicotyledonous plants. PIC (polymorphism information content) was 0.72, Shannon's information index was 1.32, these all proved that S. baicalensis had a high genetic diversity in general. Genetic differentiation among population Gst was 0.131, genetic variation among population accounted for 13.1% and genetic variation within population accounted for 86.9%. The cluster analysis showed that 10 populations S. Baicalensis were classified into 2 groups, but it was not associated with geographical distribution.