SOME CYTOLOGICAL AND AGRONOMIC CHARACTERISTICS OF PERENNIAL RYEGRASS (LOLIUM PERENNE L.) ACCESSIONS COLLECTED FROM NATURAL FLORA

The objective of this study was to determine cytogenetic and agronomic characteristics of 37 perennial ryegrass (Lolium perenne L.) accessions, collected from natural flora in Turkey, in 2010. Nuclear DNA content of the accessions was measured by flow cytometer, using propidium iodide as fluorochrome and the information was used to determine the ploidy of the accessions. The field trial was carried out in the experimental fields of the Department of Field Crops, Faculty of Agriculture, Tekirdag Namik Kemal University and five agronomic characters such as plant height, stem diameter, tiller number, fresh yield per plant, hay yield per plant were investigated for two years between 2012 and 2014. In addition, the correlation between DNA content and morphological characters was evaluated. Based on the results of the nuclear DNA content analysis, 2C nuclear DNA content of accessions vary between 5.354 and 6.004 pg. Nuclear DNA content of the accessions were correlated by counting the mitotic chromosomes of the accessions, by using a classical squash technique. It was found out that all the accessions used in chromosome counting had 2n=14 chromosomes, indicating that all the accessions used in the study were diploid. According to the results obtained from field experiments, mean plant height, stem diameter, tiller number, fresh yield per plant and dry yield per plant of perennial ryegrass accessions varied between 57.05 - 90.80 cm, 1.31 - 2.00 mm, 60.10 - 397.50 number, 163.55 - 730.00 g, 49.65 -164.00 g, respectively. Wide variation was observed among accessions used in the study for both, cytological and agronomic characters. According to the Pearson correlation analysis, hay yield per plant was positively and significantly correlated with plant height and tiller number. There was a negative correlation between DNA content and all characters, except for hay yield per plant