Molecular Markers in Kentucky Bluegrass.

Kentucky bluegrass (Poa pratensis L.) is a highly polyploid, apomictic turfgrass with tremendous variation for value added traits.  The polyploidy, small chromosome size, apomixis, and difficulty in discerning differences for certain traits limit the ability to hybridize and genetically improve Kentucky bluegrass.  One tool that can assist in genetic improvement of Kentucky bluegrass is the ability to use molecular markers for detection of hybrids, variety relationship estimations, and for evolutionary studies.  Our program has developed molecular markers for Kentucky bluegrass and other Poa species based on expressed and genomic sequences.  An M13-labelled protocol was used to genotype PCR bands using an ABI3730 instrument.  Plants rarely showed a number of bands equal to their ploidy level, especially for markers derived from expressed sequences. The average number of bands per plant was also highly variable, with more detected when markers were derived from genomic sequences.  Using these markers, we show relationships among a suite of Kentucky bluegrass varieties, and show hybrids and molecular off-types in hybridization experiments.