Evaluation of genetic variation of Iranian Festuca ovina accessions for forage yield improvement.

Festuca ovina L. widespread in Iranian mountain areas and adapt with various climates in Iran. This plant is an important grass used for pasture and Forage. The objectives of this experiment were to evaluation of genetic variation of F. ovina germplasm from various parts of Iran, and investigation of them for the presence of endophytic fungi. Endophyte-infected grasses express a range of adaptations to biotic and abiotic stresses. The seeds of 26 Festuca ovina accessions were collected from natural habitat of this grass such as Yasouj, Mashhad, Fariman, Bojnord, Shiraz, Safashahr, Semirom, Kermanshah, Khorram-Abad, Borojen and Hamadan. About 150 seeds from each accession selected randomly and planted into pots. After germination, seedlings were planted as a randomized complete block design with 3 replications in research farm of Agricultural Biotechnology Research Institute of Central region of Iran. In this study 12 traits were evaluated that included: presence of endophytic fungi, number of days to heading, number of days to pollination, plant height, canopy, panicle length, fresh and dry forage yield, crown diameter, leaf texture, leaf color, density and rust disease resistance. The presence of endophytic fungi in the seeds was determined by the rose bengal staining method. In this study, Aceto-Iron-Hematoxylin method, used for counting chromosomes. In this method, root tips were first placed in Alpha-bromo-naphtaline for 5 hours, fixed in Formaldehyde: Chromic acid (1:1) for 36 hours and then hydrolyzed in 1N NaOH at 60 ؛C for 12 min and finally stained in Hematoxylin solution for 16 hours. This study showed that Iranian F. ovina are highly infected with endophytes. Out of the 24 accessions examined, 10 accessions found to be infected with the endophyte at infection rates of between 40 to 100%. Results of counting chromosomes showed that 21 accessions were tetraploid with 28 chromosomes (2n=4x=28), 2 accessions were tetraploid with 28 chromosomes and 1 B chromosome (2n=4x=28+ 1B), 2 accessions were hexaploid with 42 chromosomes (2n=6x=42) and 1 accession was decaploid with 70 chromosomes (2n=10x=70). Results of analysis of variance showed significant differences between the accessions for all the traits. Based on mean comparison, the highest means of forage yield observed in 183, 158, 21, 166, 171, 174, 180 and 139 accessions and the highest means of seed yield observed in 183, 171, 174, 142, 166 and 131 accessions. Correlation coefficients analysis results showed that forage yield per plant has a high and positive correlation with crown diameter and canopy. Seed yield per plant has a high and positive correlation with forage yield per plant and crown diameter. Seed yield per plant has a high and negative correlation with peduncle length and days to heading. The results indicate a broad genetic base for forage and seed yield in this germplasm for selection and synthetic variety development.