Arbizu Carlos I, Bazo-Soto Isamar, Flores Joel, Ortiz Rodomiro, Blas Raul, García-Mendoza Pedro J, Sevilla Ricardo, Crossa José, Grobman Alexander
Centro de Investigación en Germoplasma Vegetal y Mejoramiento Genético de Plantas (CIGEMP), Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas (UNTRM), Chachapoyas, Peru.
Facultad de Ingenierías y Ciencias Agrarias, Universidad Nacional Toribio Rodríguez de Mendoza de Amazonas (UNTRM), Chachapoyas, Peru.
Front Plant Sci. 2025 Feb 25;16:1526670. doi: 10.3389/fpls.2025.1526670. eCollection 2025.
Peruvian maize exhibits abundant morphological diversity, with landraces cultivated from sea level (sl) up to 3,500 m above sl. Previous research based on morphological descriptors, defined at least 52 Peruvian maize races, but its genetic diversity and population structure remains largely unknown. Here, we used genotyping-by-sequencing (GBS) to obtain single nucleotide polymorphisms (SNPs) that allow inferring the genetic structure and diversity of 423 maize accessions from the genebank of Universidad Nacional Agraria la Molina (UNALM) and Universidad Nacional Autónoma de Tayacaja (UNAT). These accessions represent nine races and one sub-race, along with 15 open-pollinated lines (purple corn) and two yellow maize hybrids. It was possible to obtain 14,235 high-quality SNPs distributed along the 10 maize chromosomes of maize. Gene diversity ranged from 0.33 (sub-race Pachia) to 0.362 (race Ancashino), with race Cusco showing the lowest inbreeding coefficient (0.205) and Ancashino the highest (0.274) for the landraces. Population divergence (F) was very low (mean = 0.017), thus depicting extensive interbreeding among Peruvian maize. A cluster containing maize landraces from Ancash, Apurímac, and Ayacucho exhibited the highest genetic variability. Population structure analysis indicated that these 423 distinct genotypes can be included in 10 groups, with some maize races clustering together. Peruvian maize races failed to be recovered as monophyletic; instead, our phylogenetic tree identified two clades corresponding to the groups of the classification of the races of Peruvian maize based on their chronological origin, that is, anciently derived or primary races and lately derived or secondary races. Additionally, these two clades are also congruent with the geographic origin of these maize races, reflecting their mixed evolutionary backgrounds and constant evolution. Peruvian maize germplasm needs further investigation with modern technologies to better use them massively in breeding programs that favor agriculture mainly in the South American highlands. We also expect this work will pave a path for establishing more accurate conservation strategies for this precious crop genetic resource.
秘鲁玉米表现出丰富的形态多样性，其地方品种种植范围从海平面（sl）到海拔3500米以上。以往基于形态学描述符的研究确定了至少52个秘鲁玉米品种，但其遗传多样性和种群结构在很大程度上仍不清楚。在此，我们使用简化基因组测序（GBS）来获取单核苷酸多态性（SNP），从而推断来自国立农业大学莫利纳分校（UNALM）和国立塔亚卡亚自治大学（UNAT）基因库的423份玉米种质的遗传结构和多样性。这些种质代表了9个品种和1个亚品种，以及15个开放授粉系（紫玉米）和2个黄色玉米杂交种。在玉米的10条染色体上共获得了14235个高质量的SNP。地方品种的基因多样性范围从0.33（亚品种帕基亚）到0.362（品种安卡希诺），其中品种库斯科的近交系数最低（0.205），安卡希诺的近交系数最高（0.274）。种群分化（F）非常低（平均值 = 0.017），表明秘鲁玉米之间存在广泛的杂交。一个包含来自安卡什、阿普里马克和阿亚库乔的玉米地方品种的聚类表现出最高的遗传变异性。种群结构分析表明，这423个不同的基因型可分为10组，一些玉米品种聚集在一起。秘鲁玉米品种未能形成单系；相反，我们的系统发育树确定了两个进化枝，分别对应于根据其起源时间分类的秘鲁玉米品种组，即古老起源的或原始品种和新近起源的或次生品种。此外，这两个进化枝也与这些玉米品种的地理起源一致，反映了它们混合的进化背景和持续的进化。秘鲁玉米种质需要用现代技术进行进一步研究，以便在主要有利于南美高地农业的育种计划中更广泛地利用它们。我们还期望这项工作将为为这种珍贵的作物遗传资源制定更准确的保护策略铺平道路。
