Genome-wide association studies of Ca and Mn in the seeds of the common bean (Phaseolus vulgaris L.)

Abstract

SNP markers linked to genes controlling Ca and Mn uptake were identified in the common bean seeds using DArT-based association mapping (AM). The Ca concentration in the seeds varied between 475 and 3,100 mg kg^-1 with an average of 1,280.9 mg kg^-1 and the Mn concentration ranged from 4.87 to 27.54 mg kg^-1 with a mean of 11.76 mg kg^-1. A total of 19,204 SNP markers were distributed across 11 chromosomes that correspond to the haploid genome number of the common bean. The highest value of ΔK was determined as K = 2, and 173 common bean genotypes were split into two main subclusters as POP1 (Mesoamerican) and POP2 (Andean). The results of the UPGMA dendrogram and PCA confirmed those of STRUCTURE analysis. MLM based on the Q + K model identified a large number of markers-trait associations. Of the 19,204 SNPs, five (on Pv2, 3, 8, 10 and 11) and four (on Pv2, 3, 8 and 11) SNPs were detected to be significantly related to the Ca content of the beans grown in Bornova and Menemen, respectively in 2015. In 2016, six SNPs (on Pv1-4, 8 and 10) were identified to be significantly associated with the Ca content of the seeds obtained from Bornova and six SNPs (on Pv1-4, 8 and 10) from Menemen. Eight (on Pv3, 5 and 11) and four (on Pv2, 5 and 11) SNPs had a significant association with Mn content in Bornova in 2015 and 2016, respectively. In Menemen, eight (on Pv3, 5, 8 and 11) and 11 (on Pv1, 2, 5, 10 and 11) SNPs had a significant correlation with Mn content in 2015 and 2016, respectively.

Keywords: Association mapping; Calcium; Common bean; DArT; Manganese; SNP.