Genetic and Genotype x Environment Interaction Analysis for Agronomical and Some Morphological Traits in Half-Sib Families of Tall Fescue

Tall fescue (Festuca arundinacea Schreb.) is an outcrossing allohexaploid grass species extensively used for forage and turf worldwide. Twenty-five genotypes of tall fescue were chosen from a broad-base population and the genetic diversity was evaluated based on expressed sequence tag-simple sequence repeat molecular markers and agronomical and morphological traits. Their respective half-sib polycross progenies were also evaluated for these same traits at six environments (two locations for 3 yr). The high genotypic variation observed for plant seed yield and some morphological traits in parental genotypes and their respective progenies indicated high potential for improving these traits through targeted selection in breeding programs. Family and family x location interactions were significant for most characteristics. Narrow-sense heritability estimates were moderately high for plant seed weight (49%), number of fertile tillers (46%), panicle length (45%), and plant height (44%). These indicate that family selection methods should be more effective than individual selection. Stable families across environments were identified based on the regression coefficients, deviations from the regression, and yield potential indicating the usefulness of these parameters in the selection process for seed and forage yield improvement where additive x environment interactions are present.