Figure 2. Types and numbers of large repeat sequences in the chloroplast genomes of five Primula species.
A total of 38 Microsatellites in the P. wilsonii chloroplast genome were detected, including 28 mono-, five di-, two tri- and three tetra-nucleotide repeats. In P. poissonii , 38 SSRs loci were detected, consisting of 27 mono-, six di-, two tri- and three tetra-nucleotide repeats, respectively (Table 2). Moreover, 41 SSRs loci were spotted in P. secundiflora , and the numbers of different types are listed in Table 2. Here, we found that the one-base SSRs loci of P. wilsonii and P. poissonii were only A/T repeats. The dinucleotide repeats were AT/TA in all the five Primula species. It is shown that the trinucleotide repeats were AAT/ATT in P. wilsonii , P. anisodora , P. miyabeana and P. poissonii , but they were not present in P. secundiflora . The tetra-nucleotide repeats AAAT/AATAwere present in all the Primulaspecies. However, the AAAG/CTTT and AATT repeats only appeared inP. secundiflora . Among these SSRs loci, 30 (78.95%) were in the LSC region, six (15.79%) were in SSC region, and two (5.26%) were in the IR region of the P. wilsonii chloroplast genome.
Table 2. Types and numbers of SSRs in the chloroplast genomes of five Primula species.