Genetic gain for mineral concentration in common bean cultivars released by the Southern Brazilian Common-Bean Network

The genetic gain for mineral concentration obtained over several selection cycles is not known for common bean. The objectives of this study were to investigate the correlations between minerals, to estimate genetic gain for mineral concentration in common bean lines, and to evaluate whether the strategies used by the breeding programs of the Southern Brazilian Common-Bean Network resulted in an increase in mineral concentration in the grains. Sixteen experiments were conducted between the years 2014 and 2022 to assess 53 common bean lines obtained by seven public breeding programs in Brazil. Genetic gain for the concentration of seven minerals was determined by the generalized least squares method adapted for biennia. A significant genotype effect was observed for the concentration of most of the minerals evaluated in the different experiments. High positive correlations (r ≥ 0.70) were obtained between potassium – phosphorus and calcium – iron. Positive genetic gains were observed for the concentrations of potassium (0.59% per year), calcium (5.39% per year), and magnesium (3.39% per year), i.e. the concentrations of these macrominerals increased. Conversely, negative genetic gains were found for the concentration of phosphorus (−1.39% per year), zinc (−0.95% per year), copper (−0.51% per year), and iron (−0.22% per year). The strategies used by the breeding programs of the Southern Brazilian Common-Bean Network allow increasing the concentrations of potassium, calcium, and magnesium. However, in aiming at food and nutritional security for the next generations, changes must be implemented in the development process of new common bean cultivars regarding the other minerals.