Response of Iranian Rice Recombinant Inbred Lines (Oryza sativa L.) to Salt Stress in Seedling Stage

Study of the morphological genetic diversity of 114 lines, which have been derived from the crosses between Tarom Mahalli and Khazar cultivars, has been performed at seedling stage as completely randomized design at the normal condition and salinity stress of 8 dS.m-1 in a hydroponic system. Significant differences were detected between genotypes for all traits. Mean of comparison demonstrated that differences between all traits except root diameter were significant. Under salt stress, genetic code, number and stomata density and dry weight ratio root to stem increased. Significant difference was detected between the lines for  traits in. The highest correlation belongs to the biomass and stem dry weight. Stem length, root area density, dry weight ratio of root to stem explained the greatest biomass variations under normal conditions. In salin conditions, dry weight ratio of root to the stem, leaf area, stem length and diameter of the root explained the greatest variations of biomass,. Factor analysis showed that in normal conditions and salinity are 5 factors involved in the observed variations. Under normal condition, stem length, biomass and leaf area and under salinity stress, stem dry weight, biomass and stem length had the greatest influence on total variance. Lines were assigned in two and three groups based on biomass and also assigned into three groups based on genetic code. Tolerant lines had a high biomass. Stem length, stem dry weight can be introduced as a selection criterion in order to increase the biomass.