Quantitative Trait Locus Mapping for Potassium Use Efficiency Traits at the Seedling Stage in Wheat under Different Nitrogen and Phosphorus Treatments

Potassium is often considered one of the three most important mineral nutrient elements for plant growth, development, and fecundity. In this study, 10 traits related to K use efficiency were investigated in 10 treatments supplied with different N and P concentrations using a set of wheat (Triticum aestivum L.) recombinant inbred lines (RILs) under hydroponic culture. A total of 127 quantitative trait loci (QTLs) for the ten traits were detected on 20 chromosomes, with the exception of 4D. Of these QTLs, 35, 55, and 37 were associated with the three investigated nutrient concentration traits, four nutrient content traits, and three nutrient utilization efficiency traits, respectively. Six relatively high-frequency QTLs (RHF-QTLs) were detected in at least three treatments. A total of 16 QTL clusters (C1-C16) harboring QTLs for at least three traits were identified, which involved 68 out of the 127 QTLs (53.5%). Some important QTLs/QTL clusters may be the potential targets for the marker-assisted selection (MAS) of K efficiency in wheat.