Allozyme diversity in wild Phaseolus vulgaris: further evidence for two major centers of genetic diversity

Abstract

Allozyme analysis was performed on 83 wild Phaseolus vulgaris accessions, representing a wide geographical distribution from Mesoamerica to Argentina, to determine levels of genetic diversity and geographic patterns of variability at nine polymorphic isozyme loci. The collection can be divided into two major groups, one consisting of accessions from Mexico, Central America, Colombia and Peru, and the other consisting of accessions from Peru and Argentina. One accession from northern Peru is distinct from the two major groups, and may delineate a transition zone between the two divergent groups. The level of genetic diversity within wild P. vulgaris (Ht=0.132) is comparable with those found in other Phaseolus species. There was no significant within-accession gene diversity (Hs=0.006); however, there is a moderate level of genetic diversity (Dst=0.126) between accessions. Our results are consistent with previous studies on the genetic diversity of wild P. vulgaris using phaseolin, the major seed storage protein of beans.

Genome-wide identification and characterization of aquaporin gene family in common bean (Phaseolus vulgaris L.)

“…Wild common bean is organized into two genetically different gene pools (Mesoamerican and Andean) (Koenig and Gepts 1989;Kwak and Gepts 2009;Mamidi et al 2013), with a broad environmental distribution in Mexico and Central to South America (Cortés et al 2013). These two gene pools were independently domesticated in what is now Mexico and South America (Gepts et al 1986;Bitocchi et al 2013) about 8,000 years ago.…”

Investigation of the domestication of common bean (Phaseolus vulgaris) using multilocus sequence data

“…Two large gene pools of wild types were identified based on phaseolin seed protein variation Gepts 1990), DNA marker diversity (Becerra Velasquez and Gepts 1994;Sonnante et al 1994;Freyre et al 1996;Tohme et al 1996), morphology (Evans 1976;Gepts and Debouck 1991), isozymes (Koenig and Gepts 1989), mitochondrial DNA variation (Khairallah et al 1992) and amplified fragment length polymorphism (AFLP) (Rossi et al 2009) and short sequence repeats (SSR) ) marker data.…”

Microsatellite characterization of Andean races of common bean (Phaseolus vulgaris L.)

“…Andean beans can be distinguished from Mesoamerican beans on the basis of morphological and biochemical differences such as seed size and seed proteins as well as with various types of molecular markers (Gepts 1998). Meanwhile the races within each gene pool can be distinguished somewhat by some but not all molecular markers (Beebe et al 2000(Beebe et al , 2001Diaz and Blair 2006) and to a certain extent by allelic frequency at a limited number of isozyme loci (Koenig and Gepts 1989;Singh et al 1991c). Germplasm exchange, gene flow and crossing programs between and within the two gene pools have given rise to introgression between gene pools (Beebe et al 2001;Islam et al 2004) and between races (Diaz and Blair 2006) resulting in intermediates phenotypes that do not classify well into any single race or gene pool.…”