Data from: Nitrate reductase phylogeny of potato (Solanum sect. Petota) genomes with emphasis on the origins of the polyploid species

Solanum section Petota is taxonomically difficult, partly because of interspecific hybridization at both the diploid and polyploid levels. There is much disagreement regarding species boundaries and affiliation of species to series. Elucidating the phylogenetic relationships within the polyploids is crucial for an effective taxonomic treatment of the section and for the utilization of wild potato germplasm in breeding programs. We here infer relationships among the potato diploids and polyploids using nitrate reductase (NIA) sequence data in comparison to prior plastid phylogenies and: 1) examine genome types within section Petota, 2) show species in the polyploid series Conicibaccata, Longipedicellata, and in the Iopetalum group to be derived from allopolyploidization, 3) support an earlier hypothesis by confirming S. verrucosum as the maternal genome donor for the polyploid species S. demissum as well as species in the Iopetalum Group, 4) demonstrate that S. verrucosum is the closest relative to the maternal genome donor for species in ser. Longipedicellata, 5) support the close relationship between S. acaule and diploid species from series Megistacroloba and Tuberosa, and 6) show the North and Central American B genome species to be well distinguished from the A genome species of South America.

茄属马铃薯组（Solanum section Petota）的分类学界定极具挑战性，这主要归因于其二倍体和多倍体层级均存在种间杂交现象。目前学界在该类群的物种边界划分以及物种与各系的归属问题上存在诸多分歧。阐明该类群多倍体的系统发育关系，对于开展马铃薯组的科学分类修订，以及在育种工作中利用野生马铃薯种质资源均具有关键意义。本研究通过硝酸还原酶（NIA）序列数据，对马铃薯二倍体与多倍体类群的演化关系进行推断，并与已发表的质体系统发育研究结果进行对比，同时完成以下6项研究内容：1）明确马铃薯组内的基因组型组成；2）证实多倍体类群中的圆锥果系（Conicibaccata）、长梗系（Longipedicellata）以及Iopetalum组物种均起源于异源多倍化事件；3）通过确认疣状茄（S. verrucosum）为多倍体物种暗褐马铃薯（S. demissum）以及Iopetalum组物种的母本基因组供体，验证了此前的相关假说；4）表明疣状茄（S. verrucosum）是长梗系（ser. Longipedicellata）物种母本基因组供体的最近缘类群；5）支持野马铃薯（S. acaule）与大裂片系（Megistacroloba）和块茎系（Tuberosa）的二倍体物种具有较近亲缘关系；6）证实北美与中美洲的B基因组物种与南美洲的A基因组物种界限分明。