Development of EST-SSR Primers in Keteleeria calcarea Based on Tran-scriptome Sequencing
Keteleeria calcarea Cheng et L.K.Fu,which is an endemic and endangered species to China,has high ecological,economic and scientific research value.The aim of this study is to develop EST-SSR molecular mark-ers of Keteleeria calcarea based on transcriptome sequencing date.Searching for the SSR loci from 132 191 uni-genes of K.calcarea with MISA software,a total 6 903 SSRs were obtained,accounting for 5.22％of the total uni-genes,averagely one SSR per 12.015 kb.The repeat type of the SSR loci in K.calc area was dominated by mononucleotide repeats,followed by dinucleotide repeats and trinucleotide repeats,accounting for 55.15％,17.14％and 17.07％,respectively.By SSR molecular markers,225 pairs of primers were detected,which accounted for 69.23％of the total primers.These 225 pairs of primers amplified a clear fragment with expected size,9 pairs of which with polymorphism were identified after re-screening.These markers were tested on 25 individuals from a wild K.calcarea population,which showed that all of these loci were polymorphic.Among the 9 pairs of polymor-phic SSR locus,the average allele number(Na),effective alleles(Ne),Shannon's index(Ⅰ),observed heterozygosi-ty(Ho),expected heterozygosity(He),and polymorphic information content(PIC)were 5.111,2.668,0.963,0.456,0.461 and 0.428,respectively.The results indicate that the genetic diversity of 9 pairs of EST-SSRs primers are at a moderate level,and the development of EST-SSR markers based on transcriptome sequences are feasible and ef-fective,which will contribute to providing an experimental basis for genetic diversity analysis and facilitating the breeding programs of K.calcarea in the future.
Keteleeria calcareaTranscriptomeGenetic diversitySSRPrimers development
NETL
NSTL
万方数据
