Effect Of Osmotic Stress On Germination And Early Seedling Growth in Bread Wheat (Triticum Aestivum L.)

This research was conducted to determine the effect of 4 different osmotic pressure (0 MPa., -0.5 MPa., -1.0 MPa., -1.5 MPa.) created by polyethylene glycol (PEG-600) on germination and early seedling growth of 8 bread wheat cultivars with different response to drought (Kate A1, Karahan 99 and Tosunbey as resistant cultivars; Golia as moderate-resistance cultivar; Alpu 2001, Sultan 95, Konya 2002 and Eser as sensitive cultivars) at the at the Seed Laboratory of Field Crops Department of Agricultural Faculty of Namik Kemal University during 2009-2010 growing season. The experiment was set up in a growth chamber in the petri dishes as randomized split plot design with 4 replications. It was not observed any seed germination for all cultivars under the -1.5 MPa. osmotic pressure. However, seeds germinated under the -1.0 MPa. osmotic pressure, but none of them could seedling growth. Germination rate, root length, seedling height, root fresh weight, shoot fresh weight and shoot dry weight were significantly reduced by increasing of osmotic stress, but mean germination time and root dry weight were significantly increased. The responses of drought resistance cultivars to osmotic stress were higher than the others. So, it can be says that applications of osmotic pressure can be used as a rapid and effective technique for testing of drought resistance of wheat genotypes at germination and early seedling growth stages.