Evaluation of Germplasm for Seedling Stage Salinity Tolerance in Rice (Oryza Sativa L.)

Salinity affects rice growth and development. Mostly all growth stages from germination to maturity are affected by the salinity. Among all the stages, seedling and reproductive stages are the most sensitive stages to salinity, which results in considerable yield losses. Development of salt tolerant varieties is most feasible approach for improving the production of rice in salt affected soils as seedling stage is necessary for better crop improvement. Overall 76 rice germplasm lines were evaluated at RARS, Maruteru, West Godavari, A.P during Kharif 2020 for salinity tolerance at seedling stage. The different parameters like root length, shoot length, shoot Na+ content, shoot K+ content, Na+/K+ content and SIS (salt injury score) at 10th and 16th day were studied under hydroponics subjecting to electrical conductivity of 6 and 12 dSm-1, at a pH of 5.0. Salinity scoring during seedling stage was noted as per the modified standard evaluation score (SES) of IRRI, revealed that four genotypes FL478, MTU1290, MTU1061 and MCM109 as tolerant, 23 genotypes as moderately tolerant, 42 were susceptible and remaining seven genotypes namely BPT2848, BPT3140, Hallabhatta, MTU1271, MTU1121, BPT2846 and Krishnahamsa are highly susceptible. The phenotypic study signified that Na+/K+ ratio is the key note for salinity tolerance.