Nutritional and Fiber Quality Assessment of Native Greek Dactylis glomerata Populations

Dactylis glomerata, a perennial forage grass widely distributed in Mediterranean areas, is recognized for its adaptability and nutritional quality. This study aimed to assess the chemical composition and fiber components of ten natural populations of Dactylis glomerata in order to characterize genetic variability in nutritional and fiber traits among populations. Seeds of all populations were established in a randomized complete block design with four replicates and cultivated for two consecutive years. Forage was collected at the boot stage, and analyses were conducted for crude protein, ash, crude fiber, neutral and acid detergent fibers, acid detergent lignin, hemicellulose, cellulose, digestible dry matter, dry matter intake, and relative feed value. Combined ANOVA indicated that genotypic effects were highly significant for all traits (p ≤ 0.001), with additional significant contributions from environmental and genotype × environment interactions. Crude protein ranged from 11.74% to 14.98%, neutral detergent fiber from 56.31% to 58.43%, and relative feed value from 100.1 to 106.4 among populations. Stability index analysis identified Kefalopotamos and Filyra as the most environmentally stable populations, whereas Kori and Xyloparoiko exhibited relatively higher values in selected forage quality traits. Broad-sense heritability values were high for the majority of traits (H2 between 93.3% and 99.9%, except for hemicellulose), suggesting a strong genetic influence. Correlation analysis also revealed inverse relationships between protein content and fiber fractions and positive relationships with digestibility-related indices. Multivariate analyses revealed a clear separation between nutritional quality traits and structural fiber components, indicating consistent differentiation among populations. Overall, these results highlight the potential of local Dactylis glomerata populations as genetic resources for further evaluation in breeding and conservation programs under Mediterranean conditions.