A survey of restriction fragment length polymorphisms in tall fescue and its relatives

Abstract

Restriction fragment length polymorphisms (RFLPs) have several advantages over conventional genetic markers and as a result have received increased attention from plant breeders and geneticists. The objective of this study was to construct a tall fescue (Festuca arundinacea Schreb.) genomic library and to survey RFLPs in tall fescue and its relatives. Using plasmid pUC19 as a vector and Escherichia coli XL1-Blue cells as hosts, the first reported PstI genomic DNA library has been established from hexaploid (2n = 6x = 42) tall fescue. The genomic clones were evaluated using nine genotypes from three species of Festuca and three restriction enzymes (BamHI, EcoRI, and HindIII). One hundred and seventy-four probes gave readable results, of which 21% were repetitive and 79% single-copy. The single-copy probes revealed good polymorphism in tall fescue. Approximately 21% of the probes did not cross hybridize to any of the diploids or tetraploids or both and, therefore, represented genome-specific clones.Key words: tall fescue, genome-specific probes, genomic library, polyploids, genomic relationships