State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, 100101, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Theor Appl Genet. 2021 May;134(5):1587-1599. doi: 10.1007/s00122-021-03796-0. Epub 2021 Mar 6.
A novel Ug99-resistant wheat-Thinopyrum ponticum translocation line was produced, its chromosomal composition was analyzed and specific markers were developed. Stem rust caused by Puccinia graminis f. sp. tritici Eriks. & E. Henn (Pgt) has seriously threatened global wheat production since Ug99 race TTKSK was first detected in Uganda in 1998. Thinopyrum ponticum is near immune to Ug99 races and may be useful for enhancing wheat disease resistance. Therefore, developing new wheat-Th. ponticum translocation lines that are resistant to Ug99 is crucial. In this study, a novel wheat-Th. ponticum translocation line, WTT34, was produced. Seedling and field evaluation revealed that WTT34 is resistant to Ug99 race PTKST. The resistance was derived from the alien parent Th. ponticum. Screening WTT34 with markers linked to Sr24, Sr25, Sr26, Sr43, and SrB resulted in the amplification of different DNA fragments from Th. ponticum, implying WTT34 carries at least one novel stem rust resistance gene. Genomic in situ hybridization (GISH), multicolor fluorescence in situ hybridization (mc-FISH), and multi-color GISH (mc-GISH) analyses indicated that WTT34 carries a T5DS·5DL-Th translocation, which was consistent with wheat660K single-nucleotide polymorphism (SNP) array results. The SNP array also uncovered a deletion event in the terminal region of chromosome 1D. Additionally, the homeology between alien segments and the wheat chromosomes 2A and 5D was confirmed. Furthermore, 51 PCR-based markers derived from the alien segments of WTT34 were developed based on specific-locus amplified fragment sequencing (SLAF-seq). These markers may enable wheat breeders to rapidly trace Th. ponticum chromosomal segments carrying Ug99 resistance gene(s).
一个新型的抗 Ug99 小麦-节节麦易位系被创制，其染色体组成被分析，并开发了特异的标记。由禾柄锈菌小麦专化型（ Puccinia graminis f. sp. tritici Eriks. & E. Henn (Pgt)）引起的茎锈病自 1998 年首次在乌干达检测到 Ug99 小种 TTKSK 以来，一直严重威胁着全球小麦生产。节节麦近免疫 Ug99 小种，可能对增强小麦抗病性有用。因此，开发新的抗 Ug99 的小麦-节节麦易位系至关重要。在本研究中，创制了一个新型的小麦-节节麦易位系 WTT34。幼苗和成株期鉴定表明，WTT34 对 Ug99 小种 PTKST 表现抗性。这种抗性来源于异源亲本节节麦。利用与 Sr24、Sr25、Sr26、Sr43 和 SrB 连锁的标记筛选 WTT34，导致从节节麦扩增出不同的 DNA 片段，这意味着 WTT34 至少携带一个新的抗茎锈病基因。基因组原位杂交（GISH）、多色荧光原位杂交（mc-FISH）和多色 GISH（mc-GISH）分析表明，WTT34 携带 T5DS·5DL-Th 易位，这与小麦 660K 单核苷酸多态性（SNP）芯片结果一致。SNP 芯片还揭示了 1D 染色体末端区域的缺失事件。此外，异源片段与小麦 2A 和 5D 染色体的同源性得到了确认。此外，基于 WTT34 异源片段，开发了 51 个基于 PCR 的标记，这些标记是基于特异位点扩增片段测序（SLAF-seq）开发的。这些标记可能使小麦育种家能够快速追踪携带 Ug99 抗性基因的节节麦染色体片段。
