Genetic diversity among tall fescue ecotypes using agro-morphological traits, nutritional values and AFLP molecular markers

This study was carried out to compare agro-morphological traits and nutritive value of 25 tall fescue (Festuca arundinacea) ecotypes grown in Tehran, Iran. The experiments were carried out in a split plot design during 2016-2018 growing seasons. The results showed that there was a significant genetic variation in existing germplasm. The highest heritability was related to dry forage yield and collar diameter (88%). The low heritability levels of forage quality related traits indicated that environmental effects play a greater role in controlling this trait. The mean comparison showed that Isfahan ecotype 11 had the highest number of fertile shoots, dry forage yield and diameter of collar while ecotypes of Shahrood ecotype 9 had the highest percentage of dry mater and Dauphine genotype with 16.05% had the highest protein percentage. The number of fertile shoots (NFS) had a positive and significant correlation with dry forage yield (DFY) and plant height (PH). DFY was positively correlated with NDF (0.71) and negatively correlated with CP (-0.62). In AFLP analysis out of the 463 scored bands, 339 (68%) were polymorphic. PIC values ranged from 0.34 (EcoACA-MseCTA) to 0.10 (EcoAGC-MseCAC). The results showed that genetic distances between ecotypes based on agro-morphologic characters and nutritional values were correlated based on AFLP (r=0.41, P=0.05) results. Based on cluster analysis all genotypes were classified into 4 genotypic groups. Considerable genetic variation and high heritability estimates indicate that direct selection for increasing forage yield could be promising. However, breeding nutritional values of forage quality might be more difficult due to environmental effects.