Title: Production of tolerant lines to cold stress through physical mutation induction in rice
Author: Aliakbar Ebadi
Abstract: In this project, landrace varieties, namely Tarom Deylamani, Hashmi, Binam, and Ali Kazemi were used as plant materials. In order to determine the optimum dose of gamma-ray, seeds were irradiated with different doses (0, 200, 250, 300, 350, 400 Gy) in Gamma Cell. LD50 for the survival of seedlings was calculated in different doses for all genotypes. Then, M1 generation plant populations of different genotypes were established after irradiation with selected optimum doses. It was harvested a spike from any M1 plant. In the population of M2, plants were selected based on morphological characteristics. In the third year, 201 plants were selected based on morphological characteristics of the M3 population. All selected plants were cultivated as selective M4 lines two times (15 of March and 9 of April). 60 lines were selected based on morphological and cold resistance. Selected lines were cultivated as M5 generations with 4 parents as control cultivar with 3-replicate based on randomized complete block design. The results showed that the effect of treatment for all studied traits was significant at 1% level, which indicated good variation due to mutation. Also, the level of tolerance to cold stress in most of the mutant lines was superior to that of parental cultivars. Based on the yield trait and other quantitative and qualitative traits, 14 mutants were selected. Selected mutant lines will be evaluated next year.
Keywords: Rice, Mutation, Cold Resistance