Genomic Progress in Bermudgrass

Bermudagrass (Cynodon spp) has been grown extensively in the southeastern USA for more than 50 years as the preferred warm-season perennial grass for forage and livestock producers. Producers prefer this grass because of its pereenial growth habit, high yield, long growing season (April-October), persistence under grazing, and relatively high forage quality. In the past, bermudagrass breeding has focused on yield, quality and grazing persistence; however, the most popular cultivars were developed more than 40 years ago. In a collaborative effort involving five research institutions (University of Florida, North Carolina State University, USDA-Tifton, University of Georgia, and Noble Foundation) and seven experimental sites, a clonal association population (n~280) has been established representing most environmental conditions of the southern United States. The objectives of this study are: 1) screen a large collection of individuals to select parental lines, and 2) to find QTLs for economically important traits, such as bermudagrass stem maggot (Atherigona reversura) and nitrogen concentration. The experiments were established in summer 2014 and 2015 with two repetitions per site in a row-column design. A large volume of phenotypic data has been recorded since establishment with an emphasis on yield, quality, leaf N concentration and pest/diseases. Genotyping of the population using the genotype-by-sequence method is in progress. Results from the GWAS analysis will be presented and discussed.