Phylogene.tic differentiation of the cultivated rice., xi., Change of gene frequeney in hybrid populations of rice.

Abstract

1. In rice, when an i, ntervarietal hybrid in pro. pagated without selectijon, it is geherally found that the frequencies of genes charige with the repetition of inbreeding generations. The freduehcy of recessive hompzygoteS in successive generations of hybrids was investigated for such genes as C : c for, apiculus pigmentatiori, + : gl for glu-tinous endosperm. Rc :, rc for seed coat coloration, and Ph : ph for phenol reaction. Ih. hybrids between . varieties of the "Continental group" and the "Insular Group", genes of the formet generally tended to increase against thpse of the latter.