Variation in Physical and Chemical Characteristics of Common Bean (Phaseolus vulgaris L.) Grain along a Domestication Gradient

Botánica, Colegio de Postgraduados, Montecillo México, México.
Chemistry & Biodiversity (Impact Factor: 1.52). 12/2011; 8(12):2211-25. DOI: 10.1002/cbdv.201100102
Source: PubMed


The objective of this study was to compare six samples of Mexican wild common bean (Phaseolus vulgaris L.) against three landraces and three improved cultivars with respect to physical and chemical attributes, and the culinary quality potential of their grain. A completely randomized experimental design was used to characterize the twelve genotypes. Data were analyzed by analysis of variance and pair-wise comparison of the treatment means by the Tukey test. In addition, correlation and principal-component analysis (PCA) were carried out using twelve characteristics of raw and four of cooked wild and domesticated grains. The results show a larger variability of the physical and chemical characteristics in wild than in domesticated beans. The PCA confirmed that grain gigantism was the main physical characteristic resulting of domestication, whereas the protein and tryptophan contents tended to be higher in wild than domesticated genotypes. Some wild samples from Chihuahua and Durango, Mexico, showed to be a genetic resource to improve food quality, because of their richness in minerals, protein, lysine, tryptophan, and dietary fibers.

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