COMPARATIVE RFLP MAPPING OF AN ALLOTETRAPLOID WILD-RICE SPECIES (ORYZA-LATIFOLIA) AND CULTIVATED RICE (ORYZA-SATIVA)

The purpose of this study was to construct a comparative RFLP map of a n allotetraploid wild rice species, Oryza latifolia, and to study the relationship between the CCDD genome of O. latifolia and the AA genome of O. sativa. A set of RFLP markers, which had been previously mapped to the AA genome of cultivated rice, were used to construct the compa rative map. Fifty-eight F-2 progeny, which were derived from a single F-1 plant, were used for segregation analysis. The comparative RFLP ma p contains 149 DNA markers, including 145 genomic DNA markers from cul tivated rice, 3 cDNA markers from oat, and one known gene (waxy, from maize). Segregation patterns reflected the allotetraploid ancestry of O. latifolia, and the CC and DD genomes were readily distinguished by most probes tested. There is a high degree of conservation between the CCDD genome of O. latifolia and the AA genome of O. sativa based on o ur data, but some inversions and translocations were noted.