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波斯小麦(Triticum carthlicum,AABB)与节节麦(Aegilops tauschii,DD)杂交,杂种 F_1出现可育性。不同组合的自交结实率21.25—39.72%。细胞学研究表明,可育性是由于杂种 F_1通过两种途径形成了未减数配子:第一,一部分花粉母细胞第一次分裂消失,只发生第二次分裂。即21条染色体集中到赤道面上之后,姊妹染色单体均等分离并移向两极,形成体积均等的二分体,二分体直接发育成未减数配子。第二,细胞质提前分裂,形成再组核。在第一次分裂的后期Ⅰ和末期Ⅰ,21条染色体向细胞中央移动形成再组核,同时细胞质提前分裂,形成体积不等的二分体,其中大子细胞含全套或大部染色体,再经正常的第二次分裂发育成两个未减数配子。未减数配子受精后形成双二倍体。
Triticum carthlicum (AABB) was crossed with Aegilops tauschii (DD), and the F1 hybrid was fertile. Different combinations of self-fertility rate of 21.25-39.72%. Cytological studies have shown that fertility is due to hybrid F_1 formed by two ways of non-reduced gametes: First, part of the pollen mother cells split first disappeared, only the second division occurred. After 21 chromosomes are concentrated on the equatorial plane, the sister chromatids are equally separated and move towards the poles, forming equal-sized doubles, which directly develop into non-reducing gametes. Second, the cytoplasm prematurely splits to form a remnant nucleus. In the first division of the late Ⅰ and the end of Ⅰ, 21 chromosomes move to the center of the cell to form a recombination nucleus, while the cytoplasm prematurely divides to form a volume of doubles, in which the large cells contain a full set or most of the chromosomes, and then The normal second division developed into two non-subtractive gametes. Not diminished by the number of gametes after fertilization double diploid.