Korchanová Zuzana, Švec Miroslav, Janáková Eva, Lampar Adam, Majka Maciej, Holušová Kateřina, Bonchev Georgi, Juračka Jakub, Cápal Petr, Valárik Miroslav
Centre of the Region Haná for Biotechnological and Agricultural Research, Institute of Experimental Botany of the Czech Academy of Sciences, Olomouc, Czechia.
Department of Cell Biology and Genetics, Faculty of Science, Palacký University Olomouc, Olomouc, Czechia.
Front Plant Sci. 2022 May 13;13:897697. doi: 10.3389/fpls.2022.897697. eCollection 2022.
Powdery mildew is one of the most devastating diseases of wheat which significantly decreases yield and quality. Identification of new sources of resistance and their implementation in breeding programs is the most effective way of disease control. Two major powdery mildew resistance loci conferring resistance to all races in seedling and adult plant stages were identified in the emmer wheat landrace GZ1. Their positions, effects, and transferability were verified using two linkage maps (1,510 codominant SNP markers) constructed from two mapping populations (276 lines in total) based on the resistant GZ1 line. The dominant resistance locus was located in a 90 cM interval of chromosome 7AL and explains up to 20% of the trait variation. The recessive locus , which provides total resistance, explains up to 40% of the trait variation and was located in the distal part of chromosome 2AL. The locus was saturated with 14 PCR-based markers and delimited to a 0.99 cM region which corresponds to 4.3 Mb of the cv. Zavitan reference genome and comprises 55 predicted genes with no apparent candidate for the resistance gene. No recessive resistance gene or allele was located at the locus before, suggesting the presence of a new powdery mildew resistance gene in the GZ1. The mapping data and markers could be used for the implementation of the locus in breeding. Moreover, they are an ideal base for cloning and study of host-pathogen interaction pathways determined by the resistance genes.
白粉病是小麦最具毁灭性的病害之一，会显著降低产量和品质。鉴定新的抗性来源并将其应用于育种计划是控制该病害最有效的方法。在二粒小麦地方品种GZ1中鉴定出了两个主要的白粉病抗性位点，它们在幼苗期和成年植株期对所有小种都具有抗性。利用基于抗性GZ1品系构建的两个作图群体（共276个株系）构建的两个连锁图谱（1510个共显性SNP标记），验证了它们的位置、效应和可转移性。显性抗性位点位于7AL染色体的90 cM区间内，可解释高达20%的性状变异。提供完全抗性的隐性位点可解释高达40%的性状变异，位于2AL染色体的远端。该位点被14个基于PCR的标记饱和，并被限定在一个0.99 cM的区域，该区域对应于cv. Zavitan参考基因组的4.3 Mb，包含55个预测基因，其中没有明显的抗白粉病基因候选基因。之前在该位点未发现隐性抗性基因或等位基因，这表明GZ1中存在一个新的白粉病抗性基因。这些作图数据和标记可用于在育种中应用该位点。此外，它们是克隆和研究由抗性基因决定的宿主-病原体相互作用途径的理想基础。
