Study of morphological and genetic diversity of rice lines using microsatellite markers associated with drought tolerance traits

Background and Aim: In this study, the morphologic and genetic diversity of ۴۰ rice lines were studied using ۲۰ microsatellite (SSR) markers linked to QTLs controlling drought tolerance characteristics.Methods: Forty genotypes were studied in two environments (stress and non –stress conditions) using augmented design in the Rice Research Institute of Iran in ۲۰۱۸. . It should be noted that the experimental field irrigation was performed in both stress and non-stress environments until the second weeding (about ۳۰ days after transplanting) for all genotypes alike. Then, in the stress condition, irrigation was completely stopped until the end of the crop maturity, while in the non-stress condition, irrigation was completely done.Results: The results of phenotypic evaluation of the studied lines, it was determined that all studied genotypes, while having general hypersensitivity and decreasing growth under drought stress conditions, were different and genotypes showed different responses to drought stress. Therefore, due to the wide range of drought response, the drought tolerant lines identified in this research can be used to improve and produce new cultivars. The results of cluster analysis of morphological traits showed that L۲۷, L۳۸, L۲۹, L۴۰ and L۳۹ lines were identified as the most tolerant genotypes under drought stress. After them, the L۹, L۱۷, L۲۱, L۲۶, L۳۰, L۱۲, L۱۹, L۲۳, L۲۵ lines, Sepidrood, Khazar and Hashemi showed the highest yield under drought stress conditions. The regression analysis also showed that ۱۳ of the ۲۰ studied microsatellite markers, RM۱۱۹۴۳, RM۴۳۱, RM۱۲۰۹۱, RM۴۱۶, RM۲۳۶, RM۱۶۰۳۰, RM۵۵۵, RM۲۱۱, RM۴۲۳, RM۱۲۱۴۶, RM۵۲۰, RM۱۲۰۲۳ and RM۲۳۳A, were associated with more than one morphological trait related with drought tolerance.Conclusion: Therefore, these markers can be used in different rice breeding programs for the screening and selection of drought tolerant cultivars and lines in areas under this environmental stress.

کلیدواژه ها:

Rice ، Drought stress ، Recombinant lines ، Microsatellite markers