Investigation of Genetic Diversity and Relationships among a Set of Rice Varieties in Iraq Using Random Amplified Polymorphic DNA (RAPD) Analysis

This study is an attempt to determine the genetic diversity and relationships among seven local rice varieties (Oryza sativa L.) and one commercial genotype by using the Random Amplified Polymorphic DNA (RAPD) technique. Seven universal primers used in this study produced (110) bands across eight varieties. Of these bands, 96 bands or 87.3% were polymorphic. The size of the amplified bands ranged between 190-3620 bp. The genetic polymorphism value of each primer was determined and ranged between 83-93%. In terms of unique banding patterns, the most characteristic banding pattern was for the Amber variety with primer A13 and for the Al-abasia variety with primer P07. Genetic distances ranged from 0.177 to 0.992 among rice varieties. Cluster analyses were performed to construct a dendrogram among studied rice varieties. The cluster analysis places most of the aromatic varieties into a close relation (subcluster) showing a high level of genetic relatedness and were distinct from non-aromatic (the other subcluster) with a few of independent varieties. Interestingly, a number of varieties originating from the same sources did form well defined groups, indicating association between the RAPD patterns and the geographic origin of the varieties. Therefore, cluster analysis grouped the eight varieties into three main clusters depending on their geographic origin; their ancestor and their aroma characteristics. The information generated from this study can be used in the future for rice breeding programs.