Putative quantitative trait loci for physical and chemical components of common bean

In common bean (Phaseolus vulgaris L.), some nutritional traits such as proteins and mineral content are lower in the cultivated form as compared with the wild counterpart. To assess the feasibility of wild bean as the putative source of desirable traits such as minerals or tannins, this study was performed to identify quantitative trait loci (QTL) associated with seed mass, Ca, Fe, Zn, and tannin content in bean seed. Two-hundred-ninety-one amplified fragment length polymorphism (AFLP) markers were scored in 120 F-2:3 segregating individuals derived from a cross between cultivated 'Bayo Baranda' and wild common bean accession G-22837. Seed weight and minerals and tannin contents were quantified on the seed harvested from the 120 individual plants. Significant transgressive segregation was observed among the F2:3 individuals for some characteristics. A total of 57 AFLP markers were distributed among five linkage groups with a coverage of 497 centiMorgans (cM). Five putative QTL were significantly associated with seed mass, two with Ca, two with Fe, one with Zn, and four with tannin content in the seed. These QTL explained approximate to42, 25, 25, 15, and 42% of the phenotypic variance, respectively. Due to known environmental effect on most nutritional traits, the use of QTL with larger effects could be used to screen segregating populations that include wild genotypes, wild populations, and ancestral landraces from the region where outstanding wild populations are identified.