Tall Fescue Morphotype Specific Marker Development and Their Application.

Tall fescue (Festuca arundinacea Schreb.) is an important cool season perennial hay and pasture grass in the temperate regions of the world. There are two distinct types of tall fescue, i.e., Continental and Mediterranean. Continental germplasms are spring/summer-active and are relatively winter-hardy. Mediterranean ecotypes generally show summer dormancy and grow well at moderately low temperatures. It is difficult to morphologically distinguish the two types especially at the early growth stages. A third group, i.e. rhizomatous tall fescue, provides a low maintenance and drought tolerant turf for mid-continental areas. Attempts have been undertaken to develop morphotype specific molecular markers. Both nuclear- and chloroplast-genome specific primers amplified polymorphic fragments between the two tall fescue morphotypes. The PCR amplicons obtained from the morphotypes were purified and sequenced. In approximately 20 kb sequence reads, there were 167 polymorphic sites.  Of which 25 SNPs were from the single base substitutions and 13 insertion/deletion events. A chloroplast marker with 47 bp deletion in the Continental morphotype has consistently identified in several populations and was included in the Noble Foundation Forage Analysis core facility for discrimination of the tall fescue morphotypes. Breeding programs were undertaken to utilize beneficial traits from both the morphotypes. A set of nuclear- and chloroplast-specific molecular markers were used to identify the hybrids from crosses between the Continental and Mediterranean germplasms. Genetic similarity analysis based on molecular markers separated the fescue morphotypes into distinct clusters. Rhizomatous and Continental tall fescue formed a loose cluster which is distinct from the Mediterranean type.