Molecular mapping of the ge (s) gene controlling the super-giant embryo character in rice (Oryza sativa L.).

The giant-embryo character is useful for quality improvement in rice. Three alleles controlling embryo size have been reported at the ge locus. Based on trisomic analysis, this locus is known to reside on chromosome 7. The objective of the present study was to identify linkage between molecular markers and the ge (s) gene using an existing molecular map of rice and an F2 population derived from Hwacheongbyeo-ge (s) (super-giant embryo)/Milyang 23. The bulked-segregant method was used to screen 38 RFLPs and two microsatellite markers from rice chromosome 7. RZ395 and CDO497 flanked the ge (s) gene, at 2.4 cM and 3.4 cM, respectively. The two microsatellite markers, RM18 and RM10, were linked with ge (s) at 7.7 cM and 9.6 cM, respectively. The availability of molecular markers will facilitate selection of this grain character in a breeding program and provide the foundation for map-based gene isolation.