Genetic diversity of Iranian rice recombinant inbred lines at the reproductive stage in normal conditions and salinity

Salinity is an important limiting factor in the production of more plants, including rice. Due to the limited amount of cultivated area, identification of tolerant genotypes to environmental stresses and especially salinity is very important. The aim of this study was to investigate the genetic diversity among 114 recombinant lines derived from the intersection of local Tarom × Khazar cultivars under non stress conditions and salinity levels of 8 dS/m in reproductive stage in a completely randomized design. Combined analysis of variance showed that the differences between lines was significant for all traits. Genotypic variation coefficients also showed that the highest genetic variation among the evaluated recombinant lines was related to the number of panicles per plant. In contrast, days to 50% flowering showed the least genetic variation among these lines. In non stress and stress conditions, the highest genotypic and phenotypic correlation coefficient was observed between grain yield and number of fill grain in seedlings. Based on the cluster analysis of grain yield, the lines were classified into four groups under normal conditions and were classified into three groups under salinity conditions. The third-party lines in both cases had a higher average than the overall average. In general, the results of this study showed that there is a significant genetic variation between the studied lines in terms of salt tolerance and this variety can be used in subsequent corrective programs. Accordingly, lines 83, 81, 56, 39, 37 and 89 were the most sensitive lines and lines 107, 101, 16, 100, 84, 98, 47, 32, 14, 29, 95, 63, 5, 49, 92 and 10 were the most tolerant lines to salinity stresses of 8 dS/m and they also had higher yields and yield components. Strained lines are proposed directly for cultivating saline or for transferring salt tolerance to commercial cultivars through future breeding programs.