New Certation Gene on the First Linkage Group Found by Inter-subspecific Hybridization of Cultivated Rice

In the hybrid progenies between Japanese testers and exotic varieties of rice plants, the segregation-distortions of four marker genes belonging to the first linkage group, wx, dpl, alk and ws, were found. From the genetic behaviors of the four characters in Fr, F,, FI, F, and B,F,, it was concluded that the segregation-distortion was not caused by any of the abnormality of germination of F, seeds, duplication of genes themselves, complementary fertility genes and cytoplasmic factors, but caused by the linkage between the marker genes and a certation gene, gametophyte gene (gad). The recombination value between ga, and wx was calculated on each of the all cross combinations. Based on the linkage intensities, the pollinating ability of ga, against ga: pollen grains at the time of pollination of F1 plants was also calculated. The presence of gametophyte genes shows at least distinct information regarding reproductive isolation, and the fact that the phylogenetic differentiation widely took place in Oryra sativa species