Klaassen Michiel T, Bourke Peter M, Maliepaard Chris, Trindade Luisa M
1Plant Breeding, Wageningen University and Research, P.O. Box 386, 6700 AJ Wageningen, The Netherlands.
Department of Applied Research, Aeres University of Applied Sciences, P.O. Box 374, 8250 AJ Dronten, The Netherlands.
Euphytica. 2019;215(2):14. doi: 10.1007/s10681-018-2331-z. Epub 2019 Jan 8.
Protein content is a key quality trait for the potato starch industry. The objective of this study was to identify allele-specific quantitative trait loci (QTLs) for tuber protein content in cultivated potato ( L.) at the tetraploid level. We analysed 496 full-sib F clones in a 3-year field trial to dissect the complex genetic architecture of soluble tuber protein content. Genotypic data from a 60K single nucleotide polymorphism (SNP) array was used for SNP dosage scoring, constructing homologue specific linkage maps and assembly of a dense integrated chromosomal linkage map. From the integrated map, probabilistic multi-locus identity-by-descent (IBD) haplotypes (alleles) were estimated and used to detect associations between the IBD haplotypes and the phenotypic trait values. Moderate levels of trait heritability were estimated between 40 and 74% that correspond with previous studies. Our contemporary naive analysis identified potential additive QTLs on chromosomes , , (top arm) and across the years. Moreover, cofactor QTL analysis identified two masked QTLs on chromosomes and (lower arm). The QTLs on chromosomes , (lower arm) and are reported here for the first time. The QTLs that we identified on chromosomes , and (top arm) show overlap with previous studies for protein content in potato. Collectively the naive QTLs explained 12 to 17% of the phenotypic variance. The underlying alleles of the QTLs provided both positive and negative effects on the phenotype. Our work uncovers the complex genetic architecture of this trait and describes potential breeding strategies for improvement. As protein has emerged as a high-value component from industrial potato starch production, the dissection of the genetic architecture and subsequent improvement of this trait by breeding has great economic and environmental relevance.
蛋白质含量是马铃薯淀粉产业的一个关键品质性状。本研究的目的是在四倍体水平上鉴定栽培马铃薯（ ）块茎蛋白质含量的等位基因特异性数量性状位点（QTL）。我们在一项为期3年的田间试验中分析了496个全同胞F克隆，以剖析可溶性块茎蛋白质含量复杂的遗传结构。利用来自60K单核苷酸多态性（SNP）芯片的基因型数据进行SNP剂量评分、构建同源特异性连锁图谱以及组装密集的整合染色体连锁图谱。从整合图谱中，估计概率性多位点同源一致（IBD）单倍型（等位基因），并用于检测IBD单倍型与表型性状值之间的关联。性状遗传力估计处于中等水平，在40%至74%之间，与先前的研究结果相符。我们当代的简单分析在多年间确定了位于染色体 、 、 （长臂）和 上的潜在加性QTL。此外，辅助因子QTL分析在染色体 和 （短臂）上鉴定出两个隐性QTL。位于染色体 、 （短臂）和 上的QTL在此首次报道。我们在染色体 、 和 （长臂）上鉴定出的QTL与先前关于马铃薯蛋白质含量的研究结果存在重叠。总体而言，简单QTL解释了12%至17%的表型变异。QTL的潜在等位基因对表型既有正向影响也有负向影响。我们的工作揭示了该性状复杂的遗传结构，并描述了潜在改善的育种策略。由于蛋白质已成为工业马铃薯淀粉生产中的高价值成分，剖析该性状的遗传结构并随后通过育种加以改良具有重大的经济和环境意义。
