The development of sequence-tagged sites (STSs) in Lolium perenne L.: the application of primer sets derived from other genera

Genetic analysis, particularly the development of genetic linkage maps in f orage grass species, lags well behind other members of the Poaceae. Compara tive mapping within this family has revealed extensive conservation in gene and marker synteny among chromosomes of diverse genera. Recently, the abil ity to transfer mapped STS markers between barley and wheat has been demons trated. The transfer of mapped STS markers between cereals and forage grass es could provide PCR-based markers for comparative mapping in these species providing they amplify homologous sequences. In this study, primers derive d from three barley genes of defined function and a gene from Phalaris coer ulescens were used to amplify homologous fragments in Lolium perenne. Prime rs derived from two barley and two oat cDNA clones were also tested along w ith eight barley and two Triticum tauchii STS markers. Twenty one primer pa irs derived from 18 loci were tested. Eleven primer pairs (52%) amplified h omologous sequences in L. perenne from ten (55%) of the loci targetted. Thi rteen new STS markers were generated in L. perenne, of which ten have been mapped in barley or rye and amplify homologous sequences in L. perenne.