Phenotypic variations of wheat cultivars from the North China Plain in response to cadmium stress and associated single nucleotide polymorphisms identified by a genome-wide association study

A diverse panel of 132 wheat cultivars from the North China Plain was collected and evaluated in terms of their phenotypic variations in response to Cd stress, and subject to a genome-wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with the phenotypic variations at the seedling stage. Significant phenotypic variations with high heritability were observed among the wheat cultivars under 40 μM Cd for the studied traits, including root length (RL), shoot length (SL), root and shoot dry biomass (RDW and SDW), root and shoot Cd content (RCD and SCD), and Cd translocation factor (TF). The mixed linear model-based association analysis detected 17 novel significant marker-trait associations (MTAs), four of which were significant at a genome-wide scale. Most of the significant MTAs controlled TF and explained 17.17% to 26.47% of the phenotypic variations.