Genetic polymorphisms and phylogenetic relationships of Korean red rice(weedy rice in Oryza sativa L.) based on randomly amplified polymorphic DNA(RAPD) markers

Genetic variation and phylogenetic relationship among twenty four strains of Korean red rice, one foreign red rice and five cultivars (Oryza sativa L.) were investigated at the DNA level by using randomly amplified polymorphic DNA (RAPD) method. Twenty of 23 10-mer primers assayed, produced strong and reproducible DNA bands. The number of amplified bands from each 10-mer primer varied from 2 to 8, with an average of 5.3 bands per primer. However, an average of 0.5 band per primer was polymorphic between a Korean red rice strain and a japonica cultivar. Out of 103 different bands observed among thirty accessions by using fifteen primers, 85(82.5%) were informative to differentiate one or more accessions for the others. Particularly, many polymorphic bands were detected among accessions which detected few polymorphism by RFLP analysis. A dendrogram of the phylogenetic similarities among thirty Korean red rices and cultivars was constructed based on their DNA polymorphisms. Classification of rice accessions based on the results from RAPD analysis was differentiated into two main groups, short grain red rices which include japonica cultivars and long grain red rices which include indica and Tongil-type cultivars. This result was in accordance with previous classifications based on isozyme and RFLP analysis. From genetic analysis of F₁ and F₂ populations of a cross between a japonica cultivar, Nagdongbyeo and a Korean red rice strain with short grain type, Geumleungaengmi 33, RAPD polymorphic bands were dominant and inherited following the Mendelian ratio.