Mangino Giulio, Arrones Andrea, Plazas Mariola, Pook Torsten, Prohens Jaime, Gramazio Pietro, Vilanova Santiago
Instituto de Conservación y Mejora de la Agrodiversidad Valenciana, Universitat Politècnica de València, Valencia, Spain.
Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-Universitat Politècnica de València, Valencia, Spain.
Front Plant Sci. 2022 Mar 7;13:847789. doi: 10.3389/fpls.2022.847789. eCollection 2022.
Multi-parent advanced generation inter-cross (MAGIC) populations facilitate the genetic dissection of complex quantitative traits in plants and are valuable breeding materials. We report the development of the first eggplant MAGIC population (S3 Magic EGGplant InCanum, S3MEGGIC; 8-way), constituted by the 420 S3 individuals developed from the intercrossing of seven cultivated eggplant () and one wild relative () parents. The S3MEGGIC recombinant population was genotyped with the eggplant 5k probes SPET platform and phenotyped for anthocyanin presence in vegetative plant tissues (PA) and fruit epidermis (FA), and for the light-insensitive anthocyanic pigmentation under the calyx (PUC). The 7,724 filtered high-confidence single-nucleotide polymorphisms (SNPs) confirmed a low residual heterozygosity (6.87%), a lack of genetic structure in the S3MEGGIC population, and no differentiation among subpopulations carrying a cultivated or wild cytoplasm. Inference of haplotype blocks of the nuclear genome revealed an unbalanced representation of the founder genomes, suggesting a cryptic selection in favour or against specific parental genomes. Genome-wide association study (GWAS) analysis for PA, FA, and PUC detected strong associations with two myeloblastosis (MYB) genes similar to involved in the anthocyanin biosynthesis pathway, and with a gene which encodes for a photo-regulatory protein and may be responsible for the PUC trait. Evidence was found of a duplication of an ancestral gene with a translocation from chromosome 10 to chromosome 1 compared with the tomato genome. Parental genotypes for the three genes were in agreement with the identification of the candidate genes performed in the S3MEGGIC population. Our new eggplant MAGIC population is the largest recombinant population in eggplant and is a powerful tool for eggplant genetics and breeding studies.
多亲本高级世代互交（MAGIC）群体有助于对植物复杂数量性状进行遗传剖析，是有价值的育种材料。我们报告了首个茄子MAGIC群体（S3 Magic EGGplant InCanum，S3MEGGIC；八亲本）的构建，该群体由420个S3个体组成，这些个体来自7个栽培茄子（）和1个野生近缘种（）亲本的杂交。利用茄子5k探针SPET平台对S3MEGGIC重组群体进行基因分型，并对其营养组织（PA）和果实表皮（FA）中花青素的存在情况以及花萼下对光不敏感的花青素色素沉着（PUC）进行表型分析。7724个经过筛选的高可信度单核苷酸多态性（SNP）证实，S3MEGGIC群体的残余杂合度较低（6.87%），不存在遗传结构，携带栽培或野生细胞质的亚群体之间没有分化。对核基因组单倍型块的推断显示，奠基者基因组的代表性不均衡，这表明存在对特定亲本基因组的隐性选择。对PA、FA和PUC进行全基因组关联研究（GWAS）分析发现，与花青素生物合成途径中涉及的两个成髓细胞瘤（MYB）基因以及一个编码光调节蛋白且可能与PUC性状有关的基因存在强关联。与番茄基因组相比，发现一个祖先基因发生了重复，并从第10号染色体易位到了第1号染色体。这三个基因的亲本基因型与在S3MEGGIC群体中进行的候选基因鉴定结果一致。我们新构建的茄子MAGIC群体是茄子中最大的重组群体，是茄子遗传和育种研究的有力工具。
