College of Agronomy, Sichuan Agricultural University, Wenjiang, Chengdu 611130, China.
Institute of Ecological Agriculture, Sichuan Agricultural University, Wenjiang, Chengdu 611130, China.
Int J Mol Sci. 2018 Dec 7;19(12):3933. doi: 10.3390/ijms19123933.
Long arms of rye ( L.) chromosome 6 (6RL) carry powdery mildew resistance genes. However, these sources of resistance have not yet been successfully used in commercial wheat cultivars. The development of small segment translocation chromosomes carrying resistance may result in lines carrying the 6R chromosome becoming more commercially acceptable. However, no wheat-rye 6RL small segment translocation line with powdery mildew resistance has been reported. In this study, a wheat-rye 6RL minichromosome addition line with powdery mildew resistance was identified, and this minichromosome was derived from the segment between L2.5 and L2.8 of the 6RL chromosome arm. Following irradiation, the 6RL minichromosome divided into two smaller segments, named 6RL and 6RL, and these fragments participated in the formation of wheat-rye small segment translocation chromosomes 6DS/6RL and 6DL/6RL, respectively. The powdery mildew resistance gene was found to be located on the 6RL segment. Sixteen 6RL-specific markers were developed, and their products were cloned and sequenced. Nucleotide BLAST searches indicated that 14 of the 16 sequences had 91⁻100% similarity with nine scaffolds derived from 6R chromosome of L. Lo7. The small segment translocation chromosome 6DL/6RL makes the practical utilization in agriculture of powdery mildew resistance gene on 6RL more likely. The nine scaffolds are useful for further studying the structure and function of this small segment.
长穗偃麦草（L.）染色体 6（6RL）携带抗白粉病基因。然而，这些抗性来源尚未成功应用于商业小麦品种。携带抗性的小片段易位染色体的发展可能导致携带 6R 染色体的系更具商业吸引力。然而，尚未报道具有抗白粉病的小麦-偃麦草 6RL 小片段易位系。在这项研究中，鉴定出了一个具有抗白粉病的小麦-偃麦草 6RL 微染色体添加系，该微染色体来源于 6RL 染色体臂的 L2.5 和 L2.8 之间的片段。经过辐射处理后，6RL 微染色体分裂成两个较小的片段，分别命名为 6RL 和 6RL，这些片段分别参与了小麦-偃麦草小片段易位染色体 6DS/6RL 和 6DL/6RL 的形成。发现抗白粉病基因位于 6RL 片段上。开发了 16 个 6RL 特异性标记，克隆并测序了它们的产物。核苷酸 BLAST 搜索表明，16 个序列中的 14 个与来自 L. Lo7 的 6R 染色体的 9 个支架具有 91⁻100%的相似性。6DL/6RL 小片段易位染色体使 6RL 上的抗白粉病基因在农业中的实际利用更有可能。这 9 个支架对于进一步研究这个小片段的结构和功能很有用。
