Parent selection and progeny performance prediction based on ESTSSR markers compare with phenotypic selection in tall fescue

Although molecular markers have been successfully used to analyze genetic variability withinand among perennial forage grasses, examples of applications to benefit their breedingprograms are rare. Additionally, molecular information about effect of genetic diversity onperformance of synthetic cultivars and their application toward parental selection are limited. In this study, 25 tall fescue genotypes were selected from a base population and the genetic diversity among them was assessed using morphological (12 Agro-morphological traits) and molecular (using 50 EST-SSR primers) characteristics. For each morphological and EST-SSR evaluation, two polycross of six parental plants with contrasting levels of genetic diversity (narrow and wide) were composed and the corresponding synthetic varieties were morphologically evaluated. Average genetic diversity among parents selected for narrow polycrosses in molecular and morphological analysis was 55% and 14% lower than among parents selected for wide polycrosses, respectively. Results showed that progenies from molecularly wide polycross had significantly higher hay yield (25%), stem number (12%) and crown diameter (10%) when compare to progenies from molecularly narrow polycross.Morphological diversity did not affect these traits. On the other hand, higher morphological diversity increased days to pollination and plant height by 4.5 and 7% respectively. Results indicated that progeny performance in tall fescue can be estimated by molecular information of their parents. The results provide evidence for an efficient application of molecular markers to select genetically diverse parents especially for quantitative traits.