High Density Molecular Map of Semidwarfing Gene, sd-1, in Rice (Oryza sativa L.)

Abstract

High density molecular map of semidwarfing gene, sd-1, was constructed using 178 F₂ plants derived from the cross between the semidwarf nearisogenic line and its recurrent parent, japonica cultivar “Shiokari”. The total size of the map including nine molecular markers (five RAPD and four RFLP markers) and sd-1 was 6.4 cM. The most closely linked RAPD markers in both sides of sd-1 were OPVI0₅₀₀ and OPAE14₁₀₀₀, and the distance between them was 1.7 cM. Since sd-1 is a recessive gene, these closely linked RAPD markers will be very powerful to monitor the gene for large scale selection in breeding program.