Genetic Diversity and Population Structure in Hashemi Rice (Oryza sativa L.) Mutants Revealed by Morphological and Molecular Markers

Mutagenesis has been one of the effective methods for creating genetic diversity and plant mutants can be significant bio-resources for crop breeding and functional genomics studies. The genetic and phenotypic diversity of ۹۵ selected mutants from ۱۷ mutant populations, obtained from an EMS mutagenized rice Hashemi variety, were phenotypically and molecularly assessed in M۳ generation. Phenotypic variation of these mutants showed that grain yield components varied among the selected mutants compared to the control plants. In parallel, genetic diversity assessed by ۱۳ Inter-Simple Sequence Repeats )ISSR) primers showed that the number of amplified fragments per primer varied from ۴ (pr۱-۷) to ۱۱ (ISSR-۷, ISSR-۱۱). In general, ۱۳ primers amplified ۹۹ fragments, ۵۰ of which were polymorphic (۵۲.۹۲%). The genetic variation created by ISSR markers within ۱۷ populations varied from ۱۱.۱۱% in HM۹ (Hashemi Mutant Line number ۹) to ۴۵.۴۵% in HM۲. The average molecular polymorphism value was ۰.۲۷. In the total genetic variance, ۹۵% of differences were attributed to within-population diversity, and ۵% were related to among-populations. The Unweighted Pair-Group Method with Arithmetic mean (UPGMA) trees illustrating ISSR diversity classified the rice mutant population into seven groups, which were further supported by model-based STRUCTURE analysis. In general, the studied mutant genotypes revealed desirable genetic characteristics in populations ۱۳ and ۱۷, with em۳h۲۰۴ and em۳h۲۸۰ genotypes being the most divergent.

کلیدواژه ها:

Ethyl methane sulfonate ، ISSRs ، Phenotypic variation ، Mutagenized rice.