目的：Dasypyrumvillosum（2n=2x=14）具有对六倍体和四倍体小麦改良的潜在有益基因。由于其开放授粉性质，在种质之间和内部存在高度多样化的染色体变异。小麦DvillosumT6VS·6AL易位被广泛用于育种，主要是因为6VS片段中的基因Pm21赋予了较高且持久的白粉病抗性。然而,这种易位的广泛使用可能会缩小小麦的遗传基础。更好的解决方案是利用多样化的D.villosum种质作为小麦育种的遗传来源。对D.villosum种质之间的细胞学和遗传多态性的分析也提供了有关该物种的遗传进化信息。使用细胞遗传学和分子工具，我们分析了D.villosum种质之间的遗传多态性，并开发了共有核型，以帮助有益基因从D.villosum渗入小麦。
方法：FISH重复的多重探针，GISH和分子标记用于检测D.villosum种质之间的染色体多态性。多态信号块类型，染色体异质性和杂合性，和染色体多态信息含量用于遗传多样性分析。
结果：开发了D.villosum的共有核型，并确定了单个D.villosum染色体相对于小麦的同源状态。pSc119.2，（GAA）10和AFA家族的串联重复探针产生高分辨率信号，不仅在D.villosum染色体中显示出不同的信号模式，而且还揭示了串联重复序列在染色体和种质之间的不同分布。从13种D.villosum种质中共鉴定出106条多态性染色体，并观察到高水平的染色体杂合性和异质性。通过广泛的杂交将56个多态性染色体的子集转移到硬粒小麦中，在两个新开发的durum-D中描述了七个多态性染色体。villosum两倍体。
结论：D.villosum的共有核型和寡核苷酸FISH促进了多态性信号块的鉴定以及D.villosum种质之间高水平的染色体杂合性和异质性，在新开发的两倍体中看到。D.villosum丰富的遗传多样性和等位基因的范围，可通过倍性杂交利用，回交和重组（染色体工程），允许将生物和非生物胁迫抗性引入小麦，转化为提高产量，最终用途质量和作物可持续性。
Dasypyrum villosum (2n = 2x = 14) harbours potentially beneficial genes for hexaploid and tetraploid wheat improvement. Highly diversified chromosome variation exists among and within accessions due to its open-pollination nature. The wheat-D. villosum T6VS·6AL translocation was widely used in breeding mainly because gene Pm21 in the 6VS segment conferred high and lasting powdery mildew resistance. However, the widespread use of this translocation may narrow the genetic base of wheat. A better solution is to utilize diversified D. villosum accessions as the genetic source for wheat breeding. Analysis of cytological and genetic polymorphisms among D. villosum accessions also provides genetic evolution information on the species. Using cytogenetic and molecular tools we analysed genetic polymorphisms among D. villosum accessions and developed consensus karyotypes to assist the introgression of beneficial genes from D. villosum into wheat.
A multiplex probe of repeats for FISH, GISH and molecular markers were used to detect chromosome polymorphisms among D. villosum accessions. Polymorphic signal block types, chromosome heterogeneity and heterozygosity, and chromosome polymorphic information content were used in genetic diversity analysis.
Consensus karyotypes of D. villosum were developed, and the homoeologous statuses of individual D. villosum chromosomes relative to wheat were determined. Tandem repeat probes of pSc119.2, (GAA)10 and the AFA family produced high-resolution signals and not only showed different signal patterns in D. villosum chromosomes but also revealed the varied distribution of tandem repeats among chromosomes and accessions. A total of 106 polymorphic chromosomes were identified from 13 D. villosum accessions and high levels of chromosomal heterozygosity and heterogeneity were observed. A subset of 56 polymorphic chromosomes was transferred into durum wheat through wide crosses, and seven polymorphic chromosomes are described in two newly developed durum-D. villosum amphidiploids.
Consensus karyotypes of D. villosum and oligonucleotide FISH facilitated identification of polymorphic signal blocks and a high level of chromosomal heterozygosity and heterogeneity among D. villosum accessions, seen in newly developed amphiploids. The abundant genetic diversity of D. villosum and range of alleles, exploitable through interploid crosses, backcrosses and recombination (chromosome engineering), allow introduction of biotic and abiotic stress resistances into wheat, translating into increasing yield, end-use quality and crop sustainability.
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