Phenotypic and Molecular Marker Based Screening of Coastal Rice Landraces under Salt Stress

Traditional rice landraces of coastal areas in Bangladesh are distinct in respect to their phenotypes, responses to salt stress and yield attributes. In characterization of coastal rice landraces, 46 rice genotypes were tested for salt tolerance at their seedling and reproductive growth stages. Through the cluster analysis following standard evaluation score (SES), genotypes were divided into five categories (highly susceptible, susceptible, moderately tolerant, tolerant and highly tolerant) at their seedling stage. Three coastal genotypes, viz. chorbindi, joyni and kedgrangal mota, were grouped as highly saline tolerant at their seedling stage. In studying reproductive stage salinity screening, based on mean score values obtained from different morphological and yield parameters (plant height, number of effective tillers/hill, number of filled grains, panicle length, 100-grain weight, and straw dry weight), kutiakon and kajolshail were identified as the salinity tolerant landraces while tulsimala, dudhkalom, birindi, bushihara, lalmota, chorboleshor, lalchikon and bashful chikon were found as moderately tolerant to salinity. Finally, the molecular characterization using two simple sequence repeat (SSR) markers, viz., RM493 and RM3412 revealed holde mota, dingamoni, kedgrangal mota, sada mota, laxmima, dishari, lal chikon, kalijira, kalo khaya, khaioz, chorbindi, kajolshail, kutiakon, bamonkhir, dudhmora, sakhorkhora, mota dhan, and sorbimaloti as tolerant landraces. These identified salt-tolerant landraces can be used as promising germplasm resources for breeding salt-tolerant high-yielding rice varieties in the future.