Assessment of Salinity Stress on Traits Related to Seed Germination in Various Selected Soybean Genotypes (Glycine max)

Seed germination has an important role in the life cycle of plants and critical stages of the growth cycle, establishment and final yield. Seed germination is the most critical stage of seedling establishment which ultimately determines the successful production of the product. Salinity is one of the environmental factors reducing crop production in the world. Saline soils or irrigation the plants with saline water has the potential to dramatically reduce plant production. To study the effect of different levels of salinity on the germination of 11 soybean genotypes, a factorial experiment in a Completely Randomized Design with three replications was performed in the greenhouse of Sari Agricultural Sciences and Natural Resources University in 2013. In this experiment the first factor was salinity levels (zero, 3, 6 and 8 dS.m-1) and the second factor was genotype and eight different traits including germination percentage, germination rate, root length, root fresh weight, root dry weight, shoot length, shoot fresh weight and dry weight of shoot were evaluated. Analysis of vari ance showed that the effect of salinity and genotypes in all studied traits were significant at 1% probability level. On the other hand, with increasing levels of salinity, all traits in all genotypes decreased. Also interaction of salinity and genotypes for all traits showed significant differences. In total, in the highest levels of salinity, the highest rate and percentage of germination, root length and shoot and shoot and root dry weight were achieved in tolerant genotypes of Forrest, Hill, 032, Cokerstoart and BRAZIL17, while the lowest amounts were observed in sensitive genotypes of Bau08, Mangar and 3 COH obtained.