Bread wheat is a widely cultivated crop with production that is often negatively influenced by disease outbreaks. Biological constraints in production include the wheat rusts (leaf rust, stem rust and stripe rust) and Fusarium head blight (FHB). Different strategies are available in the control of these important fungal diseases. However, resistance breeding remains the preferred option of control as it lowers the risk of disease outbreaks and is a more cost effective and environmentally friendly approach. Many effective rust and FHB resistance genes have been discovered and successfully deployed through resistance breeding worldwide. However, some of these genes, when deployed singly, are vulnerable to evolving pathogens. In this study we aimed to develop wheat lines with the prospect of durable resistance against the rusts and FHB through combining eight resistance genes/quantitative trait loci; Lr19, Lr34/Yr18/Sr57/Pm38/Ltn1, Sr2/Yr30, Sr26, Sr39, Fhb1, Qfhs.ifa-5A-1 and Qfhs.ifa-5A-2 into a single wheat plant using marker-assisted selection. Cross and self-pollinated populations were developed to increase the frequency and homozygosity levels of resistance genes in progeny. Molecular markers were furthermore applied to determine the identity of the high molecular weight-glutenin subunits (HMW-GS) and to screen for the presence of the 1BL.1RS translocation in the final populations. We were successful in developing wheat plants containing complex sources of rust and FHB resistance and confirmed the presence of HMW-GS markers linked to strong dough strength and good bread making qualities in these genotypes.

中文翻译：

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抗多重锈病和赤霉病小麦品系的分子育种

面包小麦是一种广泛种植的作物，其产量经常受到疾病爆发的负面影响。生产中的生物限制包括小麦锈病（叶锈病、茎锈病和条锈病）和镰刀菌赤霉病（FHB）。在控制这些重要的真菌疾病方面有不同的策略。然而，抗性育种仍然是控制的首选选择，因为它降低了疾病爆发的风险，并且是一种更具成本效益和环境友好的方法。许多有效的锈病和 FHB 抗性基因已被发现并通过全球抗性育种成功部署。然而，其中一些基因在单独部署时很容易受到不断进化的病原体的影响。在这项研究中，我们旨在通过组合八个抗性基因/数量性状位点来开发具有持久抗锈病和抗FHB前景的小麦品系；使用标记辅助选择将 Lr19、Lr34/Yr18/Sr57/Pm38/Ltn1、Sr2/Yr30、Sr26、Sr39、Fhb1、Qfhs.ifa-5A-1 和 Qfhs.ifa-5A-2 整合到单个小麦植物中。开发了杂交和自花授粉种群以增加后代中抗性基因的频率和纯合度水平。此外，还应用分子标记来确定高分子量谷蛋白亚基 (HMW-GS) 的身份并筛选最终种群中 1BL.1RS 易位的存在。