COMPARATIVE RFLP MAPPING OF A WILD-RICE, ORYZA-OFFICINALIS, AND CULTIVATED RICE, ORYZA-SATIVA

A comparative RFLP map was constructed in a wild rice, Oryza officinal is, by using 139 genomic and cDNA probes that had been used previously to map RFLPs in O. sativa. Nine of the 12 chromosomes of O. officinal is were highly homosequential to those of O. sativa. A major rearrange ment of gene order was detected in chromosome 1 and small inversions w ere found in chromosomes 3 and 11. Fourteen translocated RFLP markers were found, and chromosome 11 contained a high frequency of such trans located segments. Results were consistent with meiotic and trisomic an alysis, which suggested that the genomes of O. officinalis and O. sati va were similar. Applications of comparative maps in plant breeding an d gene cloning are discussed.