Martins Davide Coelho, Rubiales Diego, Vaz Patto Maria Carlota
Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Oeiras, Portugal.
Instituto de Agricultura Sostenible, Consejo Superior de Investigaciones Científicas, Córdoba, Spain.
Front Plant Sci. 2022 Mar 24;13:842545. doi: 10.3389/fpls.2022.842545. eCollection 2022.
([Pers.] D.C.) Wint. is an important foliar biotrophic pathogen infecting grass pea ( L.), compromising their yield stability. To date, few efforts have been made to assess the natural variation in grass pea resistance and to identify the resistance loci operating against this pathogen, limiting its efficient breeding exploitation. To overcome this knowledge gap, the genetic architecture of grass pea resistance to was investigated using a worldwide collection of 182 accessions through a genome-wide association approach. The response of the grass pea collection to rust infection under controlled conditions and at the seedling stage did not reveal any hypersensitive response but a continuous variation for disease severity, with the identification of promising sources of partial resistance. A panel of 5,651 high-quality single-nucleotide polymorphism (SNP) markers previously generated was used to test for SNP-trait associations, based on a mixed linear model accounting for population structure. We detected seven SNP markers significantly associated with disease severity, suggesting that partial resistance is oligogenic. Six of the associated SNP markers were located in chromosomes 4 and 6, while the remaining SNP markers had no known chromosomal position. Through comparative mapping with the pea reference genome, a total of 19 candidate genes were proposed, encoding for leucine-rich repeat, NB-ARC domain, and TGA transcription factor family, among others. Results presented in this study provided information on the availability of partial resistance in grass pea germplasm and advanced our understanding of the molecular mechanisms of quantitative resistance to rust in grass pea. Moreover, the detected associated SNP markers constitute promising genomic targets for the development of molecular tools to assist disease resistance precision breeding.
（[波斯语] D.C.）冬锈病是一种感染草豌豆（L.）的重要叶部活体营养型病原菌，会影响其产量稳定性。迄今为止，在评估草豌豆抗性的自然变异以及鉴定对抗该病原菌的抗性基因座方面所做的工作很少，这限制了其在育种中的有效利用。为了填补这一知识空白，通过全基因组关联方法，利用来自全球的182份种质资源对草豌豆抗锈病的遗传结构进行了研究。在可控条件下和幼苗期，草豌豆种质资源对锈病感染的反应未显示出任何过敏反应，但病害严重程度存在连续变异，并鉴定出了有前景的部分抗性资源。基于考虑群体结构的混合线性模型，使用先前生成的一组5651个高质量单核苷酸多态性（SNP）标记来检测SNP与性状的关联。我们检测到7个与锈病病害严重程度显著相关的SNP标记，表明部分抗性是寡基因的。其中6个相关SNP标记位于4号和6号染色体上，而其余SNP标记的染色体位置未知。通过与豌豆参考基因组的比较定位，共提出了19个候选基因，其中包括富含亮氨酸重复序列、NB-ARC结构域和TGA转录因子家族等编码基因。本研究结果提供了草豌豆种质资源中部分抗性的信息，并加深了我们对草豌豆对锈病定量抗性分子机制的理解。此外，检测到的相关SNP标记为开发辅助抗病精准育种的分子工具提供了有前景的基因组靶点。
