Iron Biofortification of Beans Coupled with Fast Cooking Traits.

Dry bean, Phaseolus vulgaris, is an important legume for human and is recognized as a good source of minerals, including iron and zinc. Bean breeding programs have successfully increased the concentration of Fe and Zn through phenotypic selection. In addition, numerous QTL studies have been conducted to identify regions of the genome associated with increased concentration of these micronutrients in seeds but these results have yet to be employed for marker assisted breeding. Therefore we conducted a meta-analysis from seven QTL studies. Eight Meta QTL that co-localized for Fe and Zn concentration were identified across 7 chromosomes. These explained individually 10 to 27% of the phenotypic variation and could be useful candidates for marker assisted breeding to simultaneously increase seed Fe and Zn. However, all breeding efforts and QTL studies for seed Fe and Zn concentration have been conducted on dry seeds. We have also explored the mineral retention of cooked seeds and found that faster cooking genotypes retain higher levels of iron and zinc than beans that take more time to cook. Therefore we propose combining marker assisted selection for Fe and Zn in the dry seed with phenotypic selection for fast cooking time to benefit bean consumers.