Effect of temperature on vegetative and generative traits of some important rage land plant species in laboratory condition

In this rsearch, effect of pre-cool temperature on vegetative and generative characteristics of for five population Tall fescue(Festuca arunidiaceae) including: Esphan, Brojen , Kamyaran, Mashhad and bojnord, under laboratory, greenhouse. 5 populations of Festuca ovina including: Kelack, Sirachal, Gorgan Kordastan, Zanjan in greenhouse , cocksfoot (Dactylis glomerata), (Bijar, Ardebil, Karaj, Hamedan and gene bank) under laboratory, greenhouse, six population of two species, Poa pratensis and Poa trivialis in greenhouse, were compared with control. Vegetative and generative characteristics including: present of emergence, speed of emergence, seedling length, Vigor index, number of tiller and leaf area , plant height, peduncle length, panicle length, panicle number and flag leaf length up to head, fresh and dry weight and seed weights were recorded. Comparing of population Tall fescue(Festuca arunidiaceae) population of Esphan, Brojen and Kamyaran had higher value for Leaf area and tiller numbers with cold treatment than non-cold treatment. that populations of Mashad, Brojen and Esfahan had higher values for plant height, peduncle length, panicle length, seed weight, fresh and dry weight than those of other populations. Comparing of population Festuca ovina showed that seed emergence and speed of emergence, seedling length, vigor index, especially tiller number and leaf area of some population including: Kelak, Sirachal, Goragan and Kordastan were more by cold treatment than control. All 5 populations have more value of , phenological traits including: plant height, peduncle length, panicle length, panicle number and length flag leaf up to head, fresh and dry weight by cold treatment compare with control but this increasing were more in population of Sirachal and Kordastan than the other population . Population Astaneh (24066) of the species, Poa pratensis had more reproductive traits than the othe three other population . The growth degree days (GDD). all population of five species also showed less GDD of those all population which were subjected to cold treatment. It was then concluded that, it reduced flowering dates in generative stage.