벼 雄性不稔性을 利用한 集團改良에 關한 硏究 Ⅰ. 벼 集團 能動的 循環改良育種體系의 提案

Studies on Population Improvement Breeding in Rice Using Genic Male - Sterile Factor Ⅰ. An Active Recurrent Improvement Scheme of Rice Population Using Genic Male-Sterile Factor

Population improvement breeding schemes for rice using a genie male-sterile factor are outlined. The genetic male-sterility easily induced by irradiation or chemical treatment was inherited as a single recessive(msms) gene pair. The percentage of open-pollinated seeds on male- sterile plants in randomly intermating population of rice crosses are variable individually with diverse outcross ratio from 0.0% to above 30%, and also its average estimates of each population have the range from 3.7%-13.0%. A basic scheme is composited by four main flows of breeding procedures : intermating, new genes introduction, additional recurrent cycle, and pedigree or bulk nursery. Main purposes of this system are continuous accumulation of desirable genes into rice population and breakup of an undesirable tight linkage block. Modifications of the scheme and some problems relevant to this breeding flow are discussed.