Genetic variability of mineral concentrations in Festuca arundinacea Schreb.

Nine randomly chosen clones of tall fescue (Festuca arundinacea Schreb.) were mated in all possible combinations to determine the nature of genetic variation for Mg, Ca, K, and P concentrations in a broad genetic base population. General combining ability mean squares were significant for most variables, whereas specific combining ability mean squares were not significant in most instances indicating that additive genetic variance was more important. Genotype x year interactions were significant for most variables, suggesting that selection should be evaluated over many environments. Broad-sense heritability estimates based on parental and progeny variance components were generally high for P, K, Ca, and Mg but low for the ratio K/(Ca + Mg). Narrow-sense heritabilities for these minerals were close to the broad sense values since the additive genetic variance was the largest component of the total genetic variation. Correlations between mineral concentrations and herbage dry matter yield were low. It was concluded that adequate genetic variation exists to improve mineral concentration without altering herbage dry matter yields.