Genome. 1993 Jun;36(3):565-79. doi: 10.1139/g93-077.
Cytogenetic studies in Triticum monococcum (2n = 2x = 14, AA) were initiated by generating a series of primary as well as double and triple trisomics from autotriploids derived from crosses between induced autotetraploids and a diploid progenitor. Analysis of meiotic chromosome behaviour revealed that, with the exception of primary trisomics for chromosome 7A, the chromosome present in triple dose in all other trisomics formed either a bivalent plus a univalent or a trivalent (always V shaped) at diakinesis - metaphase I in approximately equal proportions. Trisomics for chromosome 7A formed a bivalent plus a univalent or a trivalent in approximately a 1:2 ratio. About 99% of the anaphase I segregations in all the trisomics were seven to one pole and eight to the other, suggesting that primary trisomics in T. monococcum form n and n + 1 meiotic products in equal proportions. The double trisomics and triple trisomics formed 5 II + 2 III and 4 II + 3 III during metaphase I, respectively. A majority of the secondary meiocytes from the double and triple trisomics possessed unbalanced chromosome numbers. All the trisomics differed phenotypically from their diploid progenitors. Single primary trisomics for chromosomes 3A and 7A produced distinct morphological features on the basis of which they could be distinguished. The phenotypes of the double and triple trisomics deviated to a greater extent from that of diploids than those of the single trisomics. Less than 50% of the progeny of all primary trisomics were trisomics themselves. Trisomic progeny were not produced in diploid female x trisomic male crosses, indicating that functional n + 1 male gametes were not generated. Diploid as well as trisomic progeny were produced in the reciprocal crosses and upon self-fertilization of the trisomics. The average frequency of trisomic progeny was 9.9%. The fertility of primary trisomics ranged from 3.8% in trisomics for chromosome 1A to 40.6% in trisomics for chromosome 2A and was significantly less than that of diploids (99.6%). The breeding behaviour and low fertility of these trisomics make their maintenance and use in cytogenetic analyses difficult.
对 2n = 2x = 14、AA 型的一粒小麦（Triticum monococcum）进行了细胞遗传学研究。该研究通过自交多倍体与二倍体亲本体细胞杂交，产生一系列的初级及双三体和三体来进行。减数分裂过程中染色体行为的分析表明，除了 7A 号染色体的初级三体外，在其他所有三体中，三倍体染色体均形成二价体和单价体或三价体（总是 V 形），在终变期-中期 I 中，它们的比例大致相等。7A 号染色体的三体形成二价体和单价体或三价体的比例大致为 1:2。在所有三体中，约有 99%的后期 I 分离是 7 个向一极，8 个向另一极，这表明一粒小麦的初级三体形成 n 和 n + 1 减数分裂产物的比例相等。双三体和三体在中期 I 分别形成 5 II + 2 III 和 4 II + 3 III。大多数来自双三体和三体的次生减数分裂细胞具有不平衡的染色体数目。所有三体与二倍体亲代在表型上均存在差异。3A 和 7A 号染色体的初级三体形成了独特的形态特征，据此可以对它们进行区分。双三体和三体的表型与二倍体相比，偏离程度比单三体更大。所有初级三体的后代中，不到 50%是三体本身。在二倍体雌性×三体雄性杂交中，没有产生三体后代，这表明没有产生有功能的 n + 1 雄配子。在正反交和三体自交中，产生了二倍体和三体后代。三体后代的平均频率为 9.9%。初级三体的育性从 1A 号染色体三体的 3.8%到 2A 号染色体三体的 40.6%不等，显著低于二倍体（99.6%）。这些三体的繁殖行为和低育性使得它们的维持和在细胞遗传学分析中的应用变得困难。
