Evaluation of germination and seedling growth characteristics of three sesame (Sesamum indicum) cultivars in salt and drought stress condition

Water deficient and salinity are the important problems in arid and semi arid areas. Germination is the critical stage in plant development. In order to evaluation of sesame (Sesamum indicum) genotypes germination and emergence characteristic to salinity and drought stress, two separate experiments were conducted at Ferdowsi University of Mashhad, Collage of Agriculture at 2009. Experimental type was completely randomized design in factorial arrangement with 4 replications. Factors included salinity at 8 levels (0, -2, -3, -4, -6, -8, -10, -12 bar),drought at 7 levels (0, -1, -2, -3, -4, -6 and -8 bar) and three sesame cultivars (Sabzevar, Kalat, Oltan). Results showed germination and emergence parameters (germination percentage, germination rate, root length, shoot length, dry weight of roots and dry weight of shoots, ratio of root length to shoot) in all genotypes were significantly affected by salinity and drought stress. Increasing salinity and drought stress, reduced all above parameters in sesame genotypes. Most negative effect on sesame genotypes germination was obtained in drought stress. Germination of sesame genotypes was reduced in salinity stress in -6 bar, but these reduce in drought stress was observed in higher potential of -2 bar. Also shoot length of sesame genotypes had more decreased in drought stress than salinity stress. Among the studied genotypes, Sabzevar and Oltan genotypes had the highest and lowest indicators respectively at two stresses. According to these results, it seems in water deficient condition and salinity fluctuations, Sabzevar genotype is the appropriate sesame genotypes for optimal seedling establishment.