Genetic Diversity of Lowland Rice (Oryza sativa L.) Genotypes in Relation to Germination Stage Oxygen Deficiency Tolerance

Rice genotypes tolerant to germination stage oxygen deficiency (GSOD) can reduce weed infestation and can help in maintaining optimum plant stand in direct-seeded rice. Out of 43 rainfed lowland rice genotypes, AC41620A with greater establishment ability and vigor index was found to be the best under submergence at the germination stage. Further, genetic diversity was studied with 47 polymorphic simple sequence repeats (SSR) markers. Allele numbers varied between 2 and 4 and all together 11 unique alleles were identified in 10 genotypes with six SSR markers such as RM339, RM1187, RM10695, RM6840, RM1183 and RM7180. Polymorphic information content value was more than 0.7 in RM235, RM219 and RM11 indicating the usefulness of these markers for genetic studies associated with GSOD sensitivity. The results from the study are useful for marker-assisted selection as well as QTL discovery for GSOD tolerance.