Identification of SSR Markers That Differentiate Bermudagrass Cultivars Derived From ‘Tifgreen'.

The release of the bermudagrass (Cynodon spp.) triploid hybrid ‘Tifgreen’ in 1956 launched an era of vegetatively propagated turfgrass. Plants with differences in phenotypes within this cultivar, or off-types, began to be identified soon after the initial plantings. For the past 50 years many of the best performing off-types have been released as new cultivars. Use of a new set of 47 simple sequence repeat (SSR) markers and 23 previously discovered genomic SSR markers, on some of the most popular somatic mutants, identified five polymorphic fragments (as compared to ‘Tifgreen’) among three cultivars, TifEagle, MiniVerde, and Tifdwarf. These polymorphisms appear to be a slight increase/decrease in microsatellite repeat number and are unique for each cultivar. Three of the five polymorphic markers display an additional allele only in the shoot tissue but not in the root tissue of ‘TifEagle’ and ‘Tifdwarf’. This finding suggests that ‘TifEagle’ and ‘Tifdwarf’ are somatic chimeras. Thus, a collection of SSRs have been identified to distinguish multiple ‘Tifgreen’-derived cultivars and these markers give insight into the nature of the mutations that exist within ‘Tifgreen’.