Evaluation of Phosphorus Efficiency in Cultivated and Wild Potato Genotypes

Phosphorus (P) deficiency is a critical constraint to cultivated potato (<i>Solanum tuberosum</i> L.) production, while wild potato germplasm is known to harbor traits that enhance tolerance to low P conditions. The aim of this study was to evaluate the tolerance to P deficiency in cultivated and wild potato accessions from a genebank to identify interesting germplasm for potato breeding. Therefore, ten wild potato accessions and 30 cultivated varieties were evaluated under high (15 mg L^-1) and low (3 mg L^-1) P regimes for various morphological, physiological, and nutrient uptake traits. Significant genotypic variation was observed across all traits, with notable interspecific differences. While low P generally reduced biomass, several genotypes, particularly <i>S. stenotomum</i> accessions, showed enhanced root growth and greater root length per unit shoot biomass. Wild accessions (GLKS 38153, GLKS 38159, GLKS 38161, and GLKS 38163; <i>S. chacoense</i>), maintained biomass through efficient internal P use, whereas others displayed high P uptake with limited growth conversion. GLKS 38159 demonstrated remarkable P efficiency, achieving high biomass with lower P uptake. Cultivated varieties, including Ikar, Tiger, Tarzan, Borka, and Fransen, displayed diverse adaptive strategies, including longer roots and sustained biomass. These findings underscore the resilience of wild potatoes to nutrient stress and provide valuable insights for breeders targeting improved P use efficiency in potato varieties.