Evaluation of seed germination characteristics and seedling growth on five ecotypes of Festuca arundinacea in response to cold treatment

     Effects of pre-chilling temperature was studied on seed characteristics including, percentage and speed of germination, seedling length, seedling dry weight, ratio of dry weight to fresh weight and vigor index, on five ecotypes of Festuca arundinacea under laboratory, greenhouse and growth chamber conditions. Tiller number and leaf area were also studied in greenhouse and growth chamber conditions. In laboratory condition, pre- chilling germination temperature (4°C) was applied by two weeks on seeds of the five ecotypes before standard germination test. In greenhouse, seeds of the five ecotypes were sownon pots under day temperature of 20±5°C and night temperature of 5-12°C and then they were subjected to cold treatment, on 4°C at stages of 15 and 35 days of seedling ages for two weeks compared to control. In growth chamber condition, the 15 days old seedlings were transferred into a cold room in 4°C for two weeks. Ecotype like Esfahan, Brojen and Kamyaran had high values for seed characteristics in growth chamber. Also, the leaf area of the ecotypes increased with cold treatment. Tiller numbers of the ecotypes, particularly the two ecotypes of Kamyaran and Mashhad were affected by cold treatment. In greenhouse condition, the ecotypes of Esfahan, Brojen and Kamyaran had higher values for leaf area and tiller numbers in cold treatment comparing to non-cold treatment. These ecotypes also had higher values for seed characteristics in response to cold treatment on the two stages of seedling growth.