Selenium effects and quantitative trait locus (QTL) mapping for mineral nutrient efficiency traits in wheat at the seedling stage

A nutrient solution culture experiment was conducted in the greenhouse to investigate the effects of selenium (Se) on biomass and the mineral nutrient efficiency of macroelements phosphorus, potassium, calcium and magnesium (P, K, Ca and Mg) and microelements iron, manganese, copper and zinc (Fe, Mn, Cu and Zn) in wheat at the seedling stage using a set of recombinant inbred lines (RILs). Quantitative trait locus (QTL) analysis was also performed for all 60 traits. The results showed that 0.1 μmol/L Se can significantly affect the phenotypic traits relation to biomass and nutrient efficiency and the corresponding QTLs. A total of 260 QTLs were located on 19 chromosomes, and 96.54% of these QTLs were only detected in one treatment. A total of 23 important QTL clusters and 31 cooperative uptake and utilization (CUU) loci that colocalized with QTLs for nutrient uptake and/or utilization of at least two elements were also identified. These CUU loci involved 190 out of the 248 QTLs (76.66%) for nutrient efficiency traits, indicating that CUU-QTLs were common for macroelements (P, K, Ca and Mg) and microelements (Fe, Mn, Cu and Zn). Additionally, these loci may be hot spots for genetic control of mineral nutrient efficiency traits.