Rapid and reliable identification of rice genomes by RFLP analysis of PCR-amplified Adh genes.

The rice genus (Oryza L.) consists of 24 species with 10 recognized genome types. With the realization of many useful genes in species of wild rice, continuous efforts have been made to understand their genomic composition and relationships. However, the identification of rice genomes has often been difficult owing to complex morphological variation and formation of allotetraploids. Here we propose a rapid and reliable method for identifying rice genomes based on the restriction sites of PCR-amplified Adh genes. The experimental procedure was as follows: (i) amplify a portion of Adh1 and Adh2 genes with the locus-specific PCR primers; (ii) digest PCR products with restriction enzymes that distinguish different genomes; and (iii) run the digested products on 1.4% agarose gel, and photograph. Using various combinations of restriction digestion of the two Adh genes, all of the rice genomes can be identified.