Diversity of common beans (Phaseolus vulgaris,Fabaceae) and conditions of production in Aguascalientes,Mexico

This study analyzes the regional diversity of common beans (Phaseolus vulgaris, Fabaceae) in Aguascalientes, Mexico, in relation to local physical, biological, cultural, and socioeconomic factors. A close direct relationship between bean diversity and the physical and biological factors and a close inverse relationship between bean diversity and the cultural and socioeconomic factors was found. Greater bean diversity was found in areas under rainfed conditions with low-input traditional agriculture where farmers with low income cultivate a great number of local heterogeneous landraces to insure some production for home use in spite of environmental stress conditions. Reduced bean diversity is cultivated under irrigated conditions with high-input modern agriculture where farmers with high income grow a few uniform improved cultivars to obtain high yields for commercial purposes. A previous study showed greater morphological variation in the seed collected in the 1940s compared to that collected in 1984. The bean variants of 1984 showed significantly earlier maturation. These findings suggest the necessity of periodic studies for a better understanding of the dynamic process of evolution of beans under continuous ecological, cultural, and socioeconomic change.