남일 돌연변이 후대계통 Namil(SA)-bl5의 단간 및 도열병 저항성에 대한 유전분석

Rice is not only one of major crops grown in the world but also the staple food in Asia. However, in modern agriculture, the genetic diversity in rice gene pool is diminishing by selection breeding. Hence, rice is readily threatened by biotic and abiotic stresses. Rice blast is one of the major threats to stable rice production. The best approach to prevent rice blast is development of rice cultivars harboring resistance gene against blast disease. National Institute of Crop Science (NICS) in Korea developed a mutant line, Namil(SA)-bl5, which has inherited short culm and rice blast resistance by treatment of sodium azide (SA). To localize favorable mutated allele types, two mapping populations were constructed by using F2 progenies derives crosses between Namil(SA)-bl5 and Milyang23 and Namil (wild type) and Milyang23. Each F2 progenies were evaluated in terms of culm length and resistance level against a rice blast isolate, 94-254 along with their parental lines. Association analyses between marker genotype on 68 SSR anchor markers and evaluated phenotype of progeny lines were adopted to localize the putative chromosomal locations involved to culm length and blast resistance. Association analyses localized two major loci on the chromosomes of middle-low region of 6 (R2=15.8%) and the distal region of 7 (R2=20.0%), and a major locus on the middle of chromosome 12 (R2=46.6%) for the reduced culm length and increased resistance level against rice blast, respectively.