Study of genetic variation of some Iranian rice (Oryza sativa) genotypes based on morphological traits, physicochemical properties and molecular markers

Assessment of genetic diversity and individual relationships in rice (Oryza sativa) germplasm collections seems to be necessary for future rice breeding program. In order to understand genetic relationships of 30 rice genotypes, nine morphological traits, seven physicochemical properties and twelve RAPD primers were used for study of 30 rice genotypes. Among morphological traits, number of unfilled grain, number of tiller, number of filled grain and plant height had the highest CV value that indicated the high range of genetic diversity for studied genotypes. Pairwise correlation of morphological traits and physicochemical properties showed plant height had a strong positive correlation with panicle length (r = 0.721, P< 0.0001). Also, ratio of white rice to paddy rice and milling ratio had a negative correlation with plant height and 1000-grain weight, respectively. Cluster analysis of physicochemical properties and morphological traits grouped all genotypes into three main clusters. A total of 105 obtained RAPD bands, a number of 35 bands were polymorphs which range 7 to 19 bands per primer. OPB-14 and OPH-12 primers shown that lowest and the highest number of bands per primers, respectively. Cluster analysis of molecular data based on UPGMA algorithm and Jaccard's similarity coefficient grouped 30 rice genotypes into three clusters. The findings of this study might provide valuable information about local rice cultivar relationships in terms of their genetic distance, and can be useful in rice breeding program.