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在甜菜育种史上,自从发现秋水仙素有独特作用以后,甜菜育种工作者便开始了诱变二倍体甜菜为四倍体甜菜来培育多倍体甜菜品种。据国内外试验证明,以普通四倍体甜菜为母本的杂交多倍体品种,杂交率仅在60％左右,产糖量一般超过系选品种的15～20％。如果将四倍体甜菜选育成雄性不育系,杂交率可达到100％,那么单位面积产糖量就会提高到另一个新水平.然而,选育四倍体不育系比选育二倍体不育系有着较多的困难。四倍体甜菜本身存在着结实率低的弊病,选育不育系其父本需要多代自交,甜菜是异花授粉自交不亲合性很强的作物,四倍体甜菜强制自交以后,结实率有明显的下降,种子发芽率有明显的降低,而且连续多代自交其不亲合现象就越发严重,
In the history of beet breeding, since the discovery of colchicine has a unique role, beet breeders began mutagenesis of diploid beet tetraploid beet to cultivate polyploid beet varieties. According to the domestic and foreign tests, the hybrid polyploid varieties that use ordinary tetraploid beet as the female parent have a cross rate of only about 60% and the sugar yield generally exceeds 15% to 20% of the selected varieties. If tetraploid beets are bred into male-sterile lines and the rate of hybridization can reach 100%, the yield of sugar per unit area will be raised to another new level. However, tetraploid sterile lines are twice as fertile Sterile lines have more difficulties. The tetraploid beet itself has the shortcomings of low seed setting rate. The male parent of CMS line needs multiple generations of selfing, and the beet is a cross self pollination self-incompatibility crop. The tetraploid beet After the seed setting rate decreased significantly, the seed germination rate significantly reduced, and more generations of self-incompatibility more serious,