Evaluation Of Salt-Tolerant Traditional Rice Varieties in Mekong Delta, Vietnam

This study was carried out from 9/2022 to 2/2023, at Can Tho University, Vietnam. This study evaluated seedling stages’ salt tolerance in nutrient solution using three electrical conductivity (EC) salt concentrations of 9.38, 12.50, and 15.63 dS/m with fifteen traditional rice varieties. Five traditional salt-tolerant rice varieties at the seedling stage (level 5) at 15.63 dS/m were selected. Furthermore, we evaluated salt tolerance at EC 9.38, 12.50, and 15.63 dS/m in the vegetative and reproductive stages of seven rice varieties (a tolerant variety, Doc Phung, a sensitive variety, IR28, and five rice salt-tolerant varieties were selected at seedling stage). This study showed that an increase in EC concentrations in the soil significantly reduced plant height, panicle/plant, panicle length, a 1000 grain weight, and yield. The addition of 9.38 dS/m EC can distinguish tolerance and sensitive genotypes. The grain yield of sensitive genotypes decreased by 90%–100% at 9.38 dS/m EC, whereas the tolerant genotypes showed <60% in grain yield reduction. Selected traditional rice varieties of Nang Cha Ran, Nep Than, Trang Lun, Gie Hanh, and Nang Tich were salt tolerant at their seedling stage and vegetative and reproductive stages were at EC 9.38 dS/m.