栽培花生或花生(ArachishypogaeaL.)是在许多发展中国家由小农种植的谷物豆类,饲料和/或收入。栽培物种的物种形成,这涉及多倍体化,然后是驯化,大大降低了其在DNA水平上的变异性。动员花生多样性是任何育种计划的先决条件,以克服困扰生产的主要制约因素并提高农民田地的产量。在这项研究中,非洲花生改良网络(GINA)汇集了1049个花生育种系,来自非洲九个国家的品种和地方品种。使用Axiom_Arachis248KSNP阵列对集合进行基因分型,并使用8229个多态性单核苷酸多态性(SNP)标记来分析该集合的遗传结构,并量化每个育种程序中的遗传多样性水平。使用dapc开发了一个监督模型,将542、35和172基因型明确地分配给西班牙人,瓦伦西亚和弗吉尼亚市场类型,分别。根据亚种和市场类型,基于距离的集合聚类显示出清晰的分组结构,73%的基因型被归类为fastigiata,而27%的基因型被归类为hypogea亚种。使用结构,全球结构得到证实,表明,在最低成员为0.8的情况下,76%的未被dapc分配的品种实际上是混合的。尤其是瓦伦西亚亚组的大多数基因型表现出混合遗传遗传的情况。结果还表明,地理起源(即东方,南部和西部非洲)没有强烈解释遗传结构。每个育种计划管理的基因多样性,通过预期杂合度测量,范围从0.25到0.39,尼日尔育种计划的多样性最低,主要是因为该计划中仅使用属于fastigiata亚种的品系。最后,我们根据育种性状和遗传多样性开发了一个由300种种质组成的核心集合。这个集合,由205个基因型的fastigiata亚种(158个西班牙和47个瓦伦西亚)和95个基因型的hypegaea亚种(所有弗吉尼亚州)组成,提高了每个个体育种程序的遗传多样性,因此是等位基因挖掘和育种的独特资源。
Cultivated peanut or groundnut (Arachis hypogaea L.) is a grain legume grown in many developing countries by smallholder farmers for food, feed, and/or income. The speciation of the cultivated species, that involved polyploidization followed by domestication, greatly reduced its variability at the DNA level. Mobilizing peanut diversity is a prerequisite for any breeding program for overcoming the main constraints that plague production and for increasing yield in farmer fields. In this study, the Groundnut Improvement Network for Africa assembled a collection of 1,049 peanut breeding lines, varieties, and landraces from 9 countries in Africa. The collection was genotyped with the Axiom_Arachis2 48K SNP array and 8,229 polymorphic single nucleotide polymorphism (SNP) markers were used to analyze the genetic structure of this collection and quantify the level of genetic diversity in each breeding program. A supervised model was developed using dapc to unambiguously assign 542, 35, and 172 genotypes to the Spanish, Valencia, and Virginia market types, respectively. Distance-based clustering of the collection showed a clear grouping structure according to subspecies and market types, with 73% of the genotypes classified as fastigiata and 27% as hypogaea subspecies. Using STRUCTURE, the global structuration was confirmed and showed that, at a minimum membership of 0.8, 76% of the varieties that were not assigned by dapc were actually admixed. This was particularly the case of most of the genotype of the Valencia subgroup that exhibited admixed genetic heritage. The results also showed that the geographic origin (i.e. East, Southern, and West Africa) did not strongly explain the genetic structure. The gene diversity managed by each breeding program, measured by the expected heterozygosity, ranged from 0.25 to 0.39, with the Niger breeding program having the lowest diversity mainly because only lines that belong to the fastigiata subspecies are used in this program. Finally, we developed a core collection composed of 300 accessions based on breeding traits and genetic diversity. This collection, which is composed of 205 genotypes of fastigiata subspecies (158 Spanish and 47 Valencia) and 95 genotypes of hypogaea subspecies (all Virginia), improves the genetic diversity of each individual breeding program and is, therefore, a unique resource for allele mining and breeding.