Association Mapping of Physiological and Morphological Traits Related to Crop Development under Contrasting Nitrogen Inputs in a Diverse Set of Potato Cultivars

• Published in: Plants (Basel) 2021-08, Vol.10 (8), p.1727
• Main Authors: Ospina Nieto, Cesar A., Lammerts van Bueren, Edith T., Allefs, Sjefke, Vos, Peter G., van der Linden, Gerard, Maliepaard, Chris A., Struik, Paul C.
• Format: Article
• Language: English
• Subjects: Agricultural production; canopy development; Chromosome 2; Chromosome 5; Chromosomes; Crop development; Cultivars; Efficiency; Gene mapping; Genome-wide association studies; genome-wide association study; Genomes; Growth models; Marker-assisted selection; Markers; Maturity; maturity type; Nitrogen; nitrogen use efficiency; Nucleotides; Physiology; Population; Potatoes; Quantitative trait loci; Radiation; Single-nucleotide polymorphism; Solanum tuberosum
• ISSN: 2223-7747; 2223-7747
• DOI: 10.3390/plants10081727

Ample nitrogen (N) is required for potato production, but its use efficiency is low. N supply strongly interacts with maturity type of the cultivar grown. We assessed whether variation among 189 cultivars grown with 75 or 185 kg available N/ha in 2 years would allow detecting quantitative trait loci (QTLs) for relevant traits. Using phenotypic data, we estimated various traits and carried out a genome-wide association study (GWAS) with kinship correction. Twenty-four traits and 10,747 markers based on single-nucleotide polymorphisms from a 20K Infinium array for 169 cultivars were combined in the analysis. N level affected most traits and their interrelations and influenced the detection of marker–trait associations; some were N-dependent, others were detected at both N levels. Ninety percent of the latter accumulated on a hotspot on Chromosome 5. Chromosomes 2 and 4 also contained regions with multiple associations. After correcting for maturity, the number of QTLs detected was much lower, especially of those common to both N levels; however, interestingly, the region on Chromosome 2 accumulated several QTLs. There is scope for marker-assisted selection for maturity, with the main purpose of improving characteristics within a narrow range of maturity types, in order to break the strong links between maturity type and traits like N use efficiency.