Evaluation of Rice (Manawthukha) Germplasm under Salt Stress at Seedling, Vegetative and Reproductive Stages through SSR Markers

Salinity, one of the abiotic stresses, is a great problem for rice production worldwide incurring substantial yield loss a great threat towards food security. In Myanmar, 3 % of total rice crops are affected by salinity every year. In this study, Manawthukha was selected because Manawthukha is one of the rice cultivars commonly cultivated in Kyaukse region, which is prone to salinity. Thirteen rice germplasms including Pokkali and control were used for identification of salt tolerant rice genotypes at the seedling stage at Biotechnology Research Department, the molecular laboratory, Kyaukse. Phenotypically, on the basis of SES and % total dry matter (TDM) reduction of the genotypes viz. MK-B1, MK-D1, MK-E, MK-F2 and Pokkali were found to be salt tolerant (ranging value SES is 12), on the other hand MK-A1, MK-D and MK-D2 were identified as moderately tolerant and MK-F4 was salt susceptible. For genotyping, Three selected SSR markers already known to be polymorphic, viz. , RM10694, RM3412b and RM336 were used to evaluate rice genotypes for rice salt tolerance and it was found that MK-B1, MK-D1, MK-E and MK-F2 were promising salt tolerant mutant lines. Thus, the salt tolerant lines can be used in further evaluation for salinity tolerance and the SSR markers used in this study proved to be valuable tools for identifying salt tolerant genes in marker assisted breeding.