Genetic diversity for seed mineral composition in the wild legume Teramnus labialis.

Teramnus labialis (L.) Spreng. is a wild, tropical legume whose seeds are collected and used as a food source by tribal populations. In order to assess the potential of this legume to provide dietary minerals for humans, fourteen diverse accessions were grown under controlled, nutrient-replete conditions and seeds were harvested for mineral analysis. The germplasm originated from Indonesia, Africa, the Caribbean, and South America. Seed concentrations of phosphorus (P), potassium (K), sodium (Na), iron (Fe), copper (Cu), manganese (Mn), and zinc (Zn) were found to fall within the range of published values for several cultivated grain legumes, while calcium (Ca) and magnesium (Mg) were higher in T. labialis seeds. Mineral concentrations across the diverse accessions showed ranges of 1.3- to 2.3-fold for the macronutrient minerals (Ca, Mg, P, K) and 1.8- to 15.9-fold for the micronutrient minerals (Fe, Cu, Mn, Zn, and Na). The existing genetic diversity in this wild legume, especially for the essential minerals Ca and Mg, could be exploited to develop T. labialis as a new cultivated legume for tropical regions of the world.