RFLP TAGGING OF A NEW SEMIDWARFING GENE IN RICE

A new rice semidwarfing gene which is not allelic to sdl, temporarily designated as sdg, might be of use as a new source of semidwarfism in rice breeding programs. We report here the identification of a DNA marker closely linked to this gene. The DNA marker was identified by testing 120 mapped rice RFLP makers as hybridization probes for Southern analysis of a pair of nearly isogenic lines with or without sdg. Linkage association of the marker with the gene was verified using a F-2 population segregating for semidwarfism. RFLP analysis showed that sng is closely linked to a single-copy DNA clone RZ182 on chromosome 5, with a distance of 4.3 centiMorgans between them. This marker may facilitate early selection for the semidwarfing gene in rice breeding programs