Esmail Samar M, Jarquín Diego, Börner Andreas, Sallam Ahmed
Wheat Disease Research Department, Plant Pathology Research Institute, Agricultural Research Center, Giza, Egypt.
Department of Agronomy, University of Florida, Gainesville, FL 32611, USA.
Comput Struct Biotechnol J. 2023 Oct 10;21:4923-4932. doi: 10.1016/j.csbj.2023.10.014. eCollection 2023.
Net blotch (NB) and powdery mildew (PM) are major barley diseases with the potential to cause a dramatic loss in grain yield. Breeding for resistant barley genotypes in combination with identifying candidate resistant genes will accelerate the genetic improvement for resistance to NB and PM. To address this challenge, a set of 122 highly diverse barley genotypes from 34 countries were evaluated for NB and PM resistance under natural infection for in two growing seasons. Moreover, four yield traits; plant height (Ph), spike length (SL), spike weight (SW), and the number of spikelets per spike (NOS) were recorded. High genetic variation was found among genotypes in all traits scored in this study. No significant phenotypic correlation was found in the resistance between PM and NB. Immune genotypes for NB and PM were identified. A total of 21 genotypes were immune to both diseases. Of the 21 genotypes, the German genotype HOR_9570 was selected as the most promising genotype that can be used for future breeding programs. Furthermore, a genome-wide association study (GWAS) was used to identify resistant alleles to PM and NB. The results of GWAS revealed a set of 14 and 25 significant SNPs that were associated with increased resistance to PM and NB, respectively. This study provided very important genetic resources that are highly resistant to the Egyptian PM and NB pathotypes and revealed SNP markers that can be utilized to genetically improve resistance to PM and NB.
网斑病（NB）和白粉病（PM）是大麦的主要病害，有可能导致谷物产量大幅损失。培育抗大麦基因型并结合鉴定候选抗性基因将加速对NB和PM抗性的遗传改良。为应对这一挑战，对来自34个国家的122个高度多样化的大麦基因型在两个生长季节的自然感染条件下进行了NB和PM抗性评估。此外，还记录了四个产量性状：株高（Ph）、穗长（SL）、穗重（SW）和每穗小穗数（NOS）。在本研究中评分的所有性状的基因型之间发现了高度的遗传变异。在PM和NB的抗性之间未发现显著的表型相关性。鉴定出了对NB和PM免疫的基因型。共有21个基因型对这两种病害均免疫。在这21个基因型中，德国基因型HOR_9570被选为最有前途的基因型，可用于未来的育种计划。此外，还利用全基因组关联研究（GWAS）来鉴定对PM和NB的抗性等位基因。GWAS结果分别揭示了一组与对PM和NB抗性增加相关的14个和25个显著单核苷酸多态性（SNP）。本研究提供了对埃及PM和NB致病型具有高度抗性的非常重要的遗传资源，并揭示了可用于遗传改良对PM和NB抗性的SNP标记。
