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已经发现二倍体马铃薯(2n=2x=24)联会消失突变体可以相当高的频率产生能育的2n 花粉粒。可以认为这样的2n 花粉粒是通过整个染色体组均衡分裂产生的,所以是第一次减数分裂重组(FDR)的产物。在联会销失突变体中,第二次减数分裂重组(SDR)配子的染色体数不平衡,导致其败育,所以可育的2n 配子就构成了一个同型的 FDR 配子群体。在6个杂交组织的306个后代个体中,发现了76个联会消失突变体,其中有23个花粉育性超过了20%。一些这样可育的突变体已成功地用作父本材料。几乎所有可育突变体均来自其双亲都可产生2n 配子的组合。另一种情况是在两个以正常亲本(只产生 n 花粉)与2n 花粉亲本的组合中,几乎所有突变体或是雄性不育,或是花粉育性低于20%。已经发现联会消失是由单隐性基因控制的,而减数分裂核重组的遗传机制还不清楚。尽管在育种上应用联会消失基因有一定困难,但还是有积极意义的。
Diploid potato (2n = 2x = 24) cascade disappearance mutants have been found to produce fertile 2n pollen grains at a relatively high frequency. It is thought that such 2n pollen grains are produced by the balanced division of the entire genome and are therefore the product of the first meiotic recombination (FDR). In the knockout mutants, the chromosome number of the second meiotic recombination (SDR) gametes is unbalanced, resulting in abortion, so fertile 2n gametes constitute a homogeneous population of FDR gametes. Of the 306 progeny individuals in six crossbreeds, 76 were found to have disappeared mutants, of which 23 had more than 20% pollen fertility. Some such fertile mutants have been successfully used as paternal material. Almost all fertile mutants come from a combination of 2n gametes that both parents produce. Another scenario is that in the combination of two normal parents (n pollen only) and 2n pollen parents almost all of the mutants are either male sterile or less than 20% pollen fertility. It has been found that disappearance of synapses is controlled by a single recessive gene, and the genetic mechanism of meiotic nuclear remodeling is unclear. Although there is some difficulty in applying the Federation to eliminate genes in breeding, it is still of positive significance.