Title: Evaluation of Primary yield of rice mutant lines in salinity stress and normal conditions
Author: Leila Bagheri
In order to reach self-sufficiency in rice production in normal and salinity conditions, it needed to introduce a new variety in both statuses. In order for primary evaluation of mutants generation 7 (M7) from parents of the Tharom Mahali, Hasani, and Anbarboo, was carried out two individual experiments in normal (Amol) and salinity conditions (Feridonkenar) as a complete randomly block design with three replications in 2017. The 10 selected relative salt tolerances with standard salt tolerance variety (FL478) and sensitive variety (Taqqing), and three parents, were evaluated with a total of 15 genotypes. In normal condition (Amol), 12 super-selected mutants, including Sheroodi variety and three parents, and a total of 16 genotypes were evaluated. One kg seeds from each mutant and check varieties were sown in the station nursery of the deputy of the rice research institute of Iran on 25th March. Transplanting was done at both sites on 24th April 2017. The plant space was 20×20 cm with a single seedling and the plot size was 3×4 m. Agronomical characteristics such as 50% days to flowering, plant height, yield components, and yield were measured. Total and head rice recovery, full grains percent, grain elongation ratio, amylose content, and gelatinization temperature were measured in the quality Lab. The obtained data for each site was individually analyzed based on a complete random block design and was compared by means of characteristics by DMRT at a 5% probability level. The results showed that the genotype effect was significant at 1% probability for plant height, 50% days to flowering, panicle number per hill, panicle length, number of filled, empty, and total grains, yield, and some few quantity and quality of grains in normal and salinity condition. The plant height of mutants was lower than Tharom Mahali and Anbarboo as check rice varieties. The rate of decrease of plant height was 5-39 percent related to check varieties in both conditions. Almost of mutants had 87-95 days after 50% flowering. The number of panicles per hill of mutants in normal conditions was 13-17 but it was 11-14 panicles per hill in salinity conditions. The mutant number of the 3200 and 215 had the highest filled grains per panicle in normal status. The highest of total grains per panicle related to the mutant number of 3215. The best milling recovery was 71 percent, which was related to the mutant numbers of 114 and 3200 in normal status. The mutant numbers 3200, 1120, 215, and 1117 had the highest yield respectively were equal to 6687.8, 6608.5, 6570.6, and 6115.8 kg/ha in normal status. The yield of mutants in salinity conditions was different between 3-7 t/ha. Except for the mutant numbers 126 and 3226, and 1126, 138, and 3227, the rest of the mutant was selected to advance the experiment in salinity and normal condition next year respectively.
Keywords: Salinity, Rice yield, Mutant, 50% flowering