摘要
EST sequences of Mentha piperita available in the public domain(NCBI) were exploited to develop SSR markers. A total of 1316 ESTs were assembled into 155 contigs and 653 singletons and of these, 110 sequences were found to contain 130 SSRs, with a frequency of1 SSR/3.4 kb. Dinucleotide repeat SSRs were most frequent(72.3%) with the AG/CT(43.8%)repeat motif followed by AT/AT(16.2%). Primers were successfully designed for 68SSR-containing sequences(62.0%). The 68 primers amplified 13 accessions of M. piperita and 54 produced clear amplicons of the expected size. Of these 54, 33(61%) were found to be polymorphic among M. piperita accessions, showing from 2 to 4 alleles with an average of2.33 alleles/SSR, and the polymorphic information content(PIC) value varied between 0.13 and 0.51(average 0.25). All the amplified SSRs showed transferability among four different species of Mentha, with a highest in Mentha arvensis(87.0%) and minimum in Mentha citrata(37.0%). The newly developed SSRs markers were found to be useful for diversity analysis, as they successfully differentiated among species and accessions of Mentha.
EST sequences of Mentha piperita available in the public domain (NCBI) were exploited to develop SSR markers. A total of 1316 ESTs were assembled into 155 contigs and 653 singletons and of these, 110 sequences were found to contain 130 SSRs, with a frequency of 1 SSR/3.4 kb. Dinucleotide repeat SSRs were most frequent (72.3%) with the AG/CT (43.8%) repeat motif followed by AT/AT (16.2%). Primers were successfully designed for 68 SSR-containing sequences (62.0%). The 68 primers amplified 13 accessions of M. piperita and 54 produced clear amplicons of the expected size. Of these 54, 33 (61%) were found to be polymorphic among M. piperita accessions, showing from 2 to 4 alleles with an average of 2.33 alleles/SSR, and the polymorphic information content (PIC) value varied between 0.13 and 0.51 (average 0.25). All the amplified SSRs showed transferability among four different species of Mentha, with a highest in Mentha arvensis (87.0%) and minimum in Mentha citrata (37.0%). The newly developed SSRs markers were found to be useful for diversity analysis, as they successfully differentiated among species and accessions of Mentha.
