National Key Facility for Crop Gene Resources and Genetic Improvement/Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
Theor Appl Genet. 2016 May;129(5):1023-34. doi: 10.1007/s00122-016-2680-8. Epub 2016 Feb 26.
Genetically stable deletion lines of Agropyron cristatum chromosome 6P in common wheat background were generated, which allowed for physical mapping of 255 6P-specific STS markers and leaf rust resistance gene(s). Chromosomal deletion lines are valuable tools for gene discovery and localization. The chromosome 6P of Agropyron cristatum (2n = 4x = 28, PPPP) confers many desirable agronomic traits to common wheat, such as higher grain number per spike, multiple fertile tiller number, and enhanced resistance to certain diseases. Although many elite genes from A. cristatum have been identified, their chromosomal locations were largely undetermined due to the lack of A. cristatum 6P deletion lines. In this study, various A. cristatum 6P deletion lines were developed using a wheat-A. cristatum 6P disomic addition line 4844-12 subjected to (60)Co-γ irradiation as well as an Aegilops cylindrica gametocidal chromosome. Twenty-six genetically stable A. cristatum 6P deletion lines in the genetic background of common wheat were obtained, and their genetic constitutions were elucidated by genomic in situ hybridization (GISH) and sequence-tagged site (STS) markers specific to A. cristatum chromosome 6P. Moreover, 255 novel chromosome 6P-specific STS markers were physically mapped to 14 regions of chromosome 6P. Field evaluation of leaf rust resistance of various deletion lines and BC1F2 populations indicated that the A.cristatum chromosome 6P-originated leaf rust resistance gene(s) was located in the region 6PS-0.81-1.00. This study will provide not only useful tools for characterization and utilization of wheat materials with alien chromosomal segments, but also novel wheat germplasms potentially valuable in wheat breeding and improvement.
在普通小麦背景下，生成了具有遗传稳定性的偃麦草 6P 染色体缺失系，这使得 255 个 6P 特异性 STS 标记和叶锈病抗性基因得以进行物理作图。染色体缺失系是基因发现和定位的有用工具。偃麦草 6P（2n=4x=28，PPPP）赋予普通小麦许多理想的农艺性状，如每穗粒数增加、多蘖数和增强对某些疾病的抗性。尽管已经鉴定出许多来自偃麦草的优良基因，但由于缺乏偃麦草 6P 缺失系，它们的染色体位置在很大程度上仍未确定。在本研究中，使用小麦-偃麦草 6P 二体附加系 4844-12 经（60）Co-γ辐射以及一个节节麦杀配子染色体，开发了各种偃麦草 6P 缺失系。在普通小麦遗传背景下获得了 26 个遗传稳定的偃麦草 6P 缺失系，并通过基因组原位杂交（GISH）和偃麦草 6P 特异性序列标记位点（STS）标记阐明了它们的遗传组成。此外，255 个新的 6P 染色体特异性 STS 标记被物理定位到 6P 染色体的 14 个区域。对各种缺失系和 BC1F2 群体的叶锈病抗性田间评价表明，来源于偃麦草 6P 的叶锈病抗性基因位于 6PS-0.81-1.00 区域。本研究不仅为具有外源染色体片段的小麦材料的鉴定和利用提供了有用的工具，而且为小麦的改良和改良提供了有价值的新小麦种质资源。
