Shaanxi Key Laboratory of Genetic Engineering for Plant Breeding, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China.
PLoS One. 2013 Aug 19;8(8):e70879. doi: 10.1371/journal.pone.0070879. eCollection 2013.
The aim of this study was to characterize a Triticum aestivum-Psathyrostachys huashanica Keng (2n = 2x = 14, NsNs) disomic addition line 2-1-6-3. Individual line 2-1-6-3 plants were analyzed using cytological, genomic in situ hybridization (GISH), EST-SSR, and EST-STS techniques. The alien addition line 2-1-6-3 was shown to have two P. huashanica chromosomes, with a meiotic configuration of 2n = 44 = 22 II. We tested 55 EST-SSR and 336 EST-STS primer pairs that mapped onto seven different wheat chromosomes using DNA from parents and the P. huashanica addition line. One EST-SSR and nine EST-STS primer pairs indicated that the additional chromosome of P. huashanica belonged to homoeologous group 7, the diagnostic fragments of five EST-STS markers (BE404955, BE591127, BE637663, BF482781 and CD452422) were cloned, sequenced and compared. The results showed that the amplified polymorphic bands of P. huashanica and disomic addition line 2-1-6-3 shared 100% sequence identity, which was designated as the 7Ns disomic addition line. Disomic addition line 2-1-6-3 was evaluated to test the leaf rust resistance of adult stages in the field. We found that one pair of the 7Ns genome chromosomes carried new leaf rust resistance gene(s). Moreover, wheat line 2-1-6-3 had a superior numbers of florets and grains per spike, which were associated with the introgression of the paired P. huashanica chromosomes. These high levels of disease resistance and stable, excellent agronomic traits suggest that this line could be utilized as a novel donor in wheat breeding programs.
本研究旨在对小麦-华山新麦草（2n=2x=14，NsNs）易位系 2-1-6-3 进行特征描述。利用细胞学、基因组原位杂交（GISH）、EST-SSR 和 EST-STS 技术对单体型 2-1-6-3 植株进行了分析。结果表明，该易位系含有两条华山新麦草染色体，减数分裂时的构型为 2n=44=22Ⅱ。我们从亲本和华山新麦草添加系的 DNA 中筛选了 55 对 EST-SSR 和 336 对 EST-STS 引物，这些引物分别映射到 7 条不同的小麦染色体上。1 对 EST-SSR 和 9 对 EST-STS 引物表明，华山新麦草的附加染色体属于同源群 7，其中 5 个 EST-STS 标记（BE404955、BE591127、BE637663、BF482781 和 CD452422）的诊断片段被克隆、测序并进行了比较。结果表明，华山新麦草和单体型添加系 2-1-6-3 的扩增多态性带具有 100%的序列一致性，被命名为 7Ns 单体型添加系。在田间对单体型添加系 2-1-6-3 进行了成株期抗叶锈病的评价，发现其 7Ns 基因组染色体中有一对携带新的抗叶锈病基因。此外，2-1-6-3 小麦品系每穗小花数和粒数较多，这与华山新麦草染色体的导入有关。这些高水平的抗病性和稳定、优良的农艺性状表明，该系可作为小麦育种计划中的一个新的供体。
