Vatter Thomas, Maurer Andreas, Kopahnke Doris, Perovic Dragan, Ordon Frank, Pillen Klaus
Institute for Resistance Research and Stress Tolerance, Julius Kuehn-Institute, Federal Research Centre for Cultivated Plants, Quedlinburg, Germany.
Institute of Agricultural and Nutritional Sciences, Chair of Plant Breeding, Martin Luther University Halle-Wittenberg, Halle, Germany.
PLoS One. 2017 Oct 26;12(10):e0186803. doi: 10.1371/journal.pone.0186803. eCollection 2017.
The net form of net blotch caused by the necrotrophic fungus Pyrenophora teres f. teres is a major disease of barley, causing high yield losses and reduced malting and feed quality. Exploiting the allelic richness of wild barley proved to be a valuable tool to broaden the genetic base of resistance of modern elite cultivars. In this study, a SNP-based nested association mapping (NAM) study was conducted to map QTL for P. teres resistance in the barley population HEB-25 comprising 1,420 lines derived from BC1S3 generation. By scoring the percentage of infected leaf area followed by calculation of the average ordinate (AO) and scoring of the reaction type (RT) in two-year field trials a large variability of net blotch resistance across and within families of HEB-25 was observed. Genotype response to net blotch infection showed a range of 48.2% for AO (0.9-49.1%) and 6.4 for RT (2.2-8.6). NAM based on 5,715 informative SNPs resulted in the identification of 24 QTL for resistance against net blotch. Out of these, six QTL are considered novel showing no correspondence to previously reported QTL for net blotch resistance. Overall, variation of net blotch resistance in HEB-25 turned out to be controlled by small effect QTL. Results indicate the presence of alleles in HEB-25 differing in their effect on net blotch resistance. Results provide valuable information regarding the genetic architecture of the complex barley-P. teres f. teres interaction as well as for the improvement of net blotch resistance of elite barley cultivars.
由坏死营养型真菌网斑柄锈菌（Pyrenophora teres f. teres）引起的大麦网斑病的净斑形式是大麦的一种主要病害，会导致高产损失以及麦芽品质和饲料品质下降。利用野生大麦丰富的等位基因库被证明是拓宽现代优良品种抗性遗传基础的一种有价值的工具。在本研究中，开展了一项基于单核苷酸多态性（SNP）的巢式关联作图（NAM）研究，以在包含1420个来自BC1S3代品系的大麦群体HEB - 25中定位对网斑柄锈菌抗性的数量性状位点（QTL）。通过在两年的田间试验中对感染叶面积的百分比进行评分，随后计算平均纵坐标（AO）并对反应类型（RT）进行评分，观察到HEB - 25家系间和家系内对网斑病抗性存在很大变异性。对网斑病感染的基因型反应显示，AO的范围为48.2%（0.9 - 49.1%），RT的范围为6.4（2.2 - 8.6）。基于5715个信息性SNP的NAM鉴定出了24个抗网斑病的QTL。其中，有6个QTL被认为是新的，与先前报道的网斑病抗性QTL没有对应关系。总体而言，HEB - 25中网斑病抗性的变异结果表明受微效QTL控制。结果表明HEB - 25中存在对等网斑病抗性影响不同的等位基因。研究结果为复杂的大麦 - 网斑柄锈菌相互作用的遗传结构以及优良大麦品种网斑病抗性的改良提供了有价值的信息。
