MINERAL CONTENT IN SEEDS OF NATIVE POPULATIONS OF COMMON BEAN (Phaseolus vulgaris L.)

Common bean (Phaseolus vulgaris L.) is a basic staple product for the Mexican diet and gastronomy. It supplies proteins, carbohydrates, vitamins, fiber and secondary metabolites, as well as a wide range of mineral macro and microelements, such as Iron (Fe) and Zinc (Zn). Deficiencies of either element are associated to poor nutrition and health problems. This study evaluated mineral content in seeds from a collection of 57 common bean populations native from four regions of Oaxaca: Valles Centrales, Sierra Norte, Sierra Sur and Mixteca. The populations were sown in San Agustin Amatengo, Oaxaca during the 2014 Spring-Summer season under rainfed conditions using a randomized complete blocks design with four replications. At harvest time, a composite sample of 500 g of seed was obtained per population. The evaluation of mineral content was performed by atomic absorption and UVVis spectrophotometry based on reference standards. Analysis of variance detected significant differences (P <= 0.01) both among and within groups for all the evaluated minerals. The accession groups from Valles Centrales and Sierra Norte showed the highest frequency of large values in micro and macro elements. The evaluation also detected high values of macro and micro nutrients in accessions P-06, P-60, P-67, P-73, P-75 and P-79. Regarding Fe and Zn content, the outstanding accessions were P-01, P-03, P-04, P-06 and P-07.