Overview of the genus Phaseolus by Alfonso Delgado and Susana Gama Lopez (in Spanish)

In a recent issue of Revista Digital Universitaria of UNAM (National Autonomous University of Mexico), Alfonso Delgado and Susana Gama Lopez present – in Spanish – a synopsis of the ecological distribution of the genus Phaseolus in Mexico, the core distribution area of this genus.

A few salient points:

1/ There are currently 52 species distributed in the Mexican territory of which 31 are endemic. The highest species richness is concentrated in the staes of Durango, Jalisco, and Oaxaca, the lowest in the Yucatan peninsula, Tabasco, and Tlaxcala.

2/ The majority of species (49) grow in temperate to cold environments, subhumid to subarid, in juniper, pine, pine-oak, and oak forests.

3/ Lima bean (P. lunatus), distributed from the north of Argentina to Mexico, has the broadest ecological distribution as it occurs in  14 types of vegetation, more than any other Phaseolus species.

4/ Species diversity of Phaseolus will probably affected because the environments in which species currently are distributed will suffer the brunt of temperature increases: see point 2/ above.

5/ Ex situ conservation efforts of Phaseolus germplasm in Mexico include those organized by INIFAP (some 30,000 accessions) and SAGARPA (Centro Nacional de Recursis Geneticos in Tepatitlan de Morelos, Jalisco)

6/ In situ conservation projects include the MILPA project, which was funded by the McKnight Foundation, and the program of ANPs (Areas Naturales Protegidas)

7/ One species – Phaseolus leptophyllus – appears to be extinct. It was described first in the 18th centure in mountains near Chilpancingo in the state of Guerrero, but has not been collected since.