| چکیده انگلیسی مقاله |
Extended abstract Introduction: One of the ways to overcome the limitation of fresh water and lack of sufficient water reserves for agriculture is to use unconventional water such as seawater. Salinity stress is the most important abiotic stress in seawater application. Sesame is one of the most important oilseeds in agriculture with protein, oil content, and high antioxidant content in food, medicine, and industry. Identification and planting of salinity tolerant genotypes of a plant species is one of the effective and valuable strategies in reducing the effects of salinity stress. Germination, and seedling growth stages and seedling establishment are salinity-sensitive in most plants. Therefore, for improvement of abiotic stress tolerance in plants, it is necessary to study the traits and indicators related to tolerance in the germination stage. Material and Methods: To investigate the germination indices and seedling traits of 10 sesame genotypes under saline conditions, a factorial experiment was conducted in a completely randomized design with three replications at the laboratory of Plant Breeding Department of Sari University of Agricultural Sciences and Natural Resources in 2020. The first factor The second factor includes 5 salinity levels (control (no seawater), 3, 6, 9 and 11 dS (Siemens per meter). Was the result of mixing Caspian Sea water and urban water. The number of germinated seeds was counted during eight days of salinity stress then germination percentage, time required up to 50% germination, seedling vigor index and germination rate was calculated and on the eighth day, the dry weight of the radicle and the plumule, the fresh weight of the radicle and plumule, radicle length, plumule length and seedling dry weight (P=%1) were measured. Results: The results of analysis of variance showed the significance of the effect of different salinity levels, the effect of genotype and the interaction of salinity and genotype for all calculated indices (P=%1). Comparison of the mean interaction of different levels of salinity and cultivars and landraces showed that with increasing salinity, all the studied traits except for the time to reach fifty percent germination decreased. Among the studied cultivars, Oltan cultivar has the highest value in germination percentage (100%), germination rate (24.17 seeds per day), seedling vigor index (5.03), plumule length (55.67 mm), radicle length (70 mm), plumule fresh weight (62 mg), radicle fresh weight (45 mg), plumule dry weight (4.77 mg), seedling dry weight (6/23 Mg) and the lowest amount in the time required up to 50% germination (24.17 hours) in the control level. In contrast, Pakistani cultivar has the lowest value in germination rate (3.06 seeds per day), seedling vigor index (1), plumule length (8.33 mm), radicle length (3 mm), plumule fresh weight (10 mg), radicle fresh weight (2 mg), plumule dry weight (0.57 mg), seedling dry weight (0.84 mg) and was highest value in the time required up to 50% germination (24.17 hours) in the salinity level of 11 dS / m. Using the results of this experiment, among the studied cultivars, Oltan cultivar was selected as the most tolerant and Pakistani cultivar as the most sensitive cultivar to salinity stress at the germination stage. Conclusion: The studied cultivars and landraces showed different reactions in the study of germination indices in the treatment with salinity from seawater. The high significant difference in this experiment indicated the high genetic diversity among the studied genotypes. It is possible to choose from these genotypes for salinity tolerance breeding programs in sesame plant. |