U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska
Document Type
Article
Date of this Version
3-2017
Citation
ANNUAL REPORT OF THE BEAN IMPROVEMENT COOPERATIVE, No. 60, March 2017. Published by USDA.
Abstract
Beans (Phaseolus spp.) and maize are major staples in Mexican food. Studying the genetic diversity of wild and cultivated Phaseolus species is a major challenge for conservation and exploitation. We suggest that new information should contribute to improving our knowledge of intra and inter-species genetic variability as well as the genetic relationships among domesticated species of Phaseolus in México. In addition, the increased knowledge could improve the conservation of Phaseolus genetic resources throughout Mexico and provide a global overview of the importance of an integrative use of Phaseolus in common bean breeding (Hernández-Delgado et al., 2015). This work had two aims: to characterize the genetic variability among and within four domesticated species of Phaseolus, and to estimate the relationship and genetic structure of populations in germplasm of P. acutifolius, P. coccineus, P. lunatus and P. vulgaris.
The intra- and inter-species variability and genetic relationships in germplasm from P. acutifolius, P. coccineus, P. lunatus, and P. vulgaris was analyzed. Twelve accessions of each species were collected from throughout Mexico and compared with the following controls: P. albescens, P. coccineus subsp. striatus var. purpurascens, P. parvifolius, and P. xolocotzii as well as the bred cultivars (P. vulgaris) Negro Jamapa, Negro Papaloapan, Pinto Centauro, and Pinto Coloso. Germplasm was analyzed with 15 simple sequence repeat (SSR) markers, six genic and nine inter-genic, which amplified 292 alleles (225 intergenic and 67 genic markers). Values of expected (He) and observed (Ho) heterozygosity per accession and SSR were calculated, and Molecular Analysis of Variance (AMOVA) was performed. Genetic structure of populations and coancestry values were determined using STRUCTURE V 2.3.3 (Pritchard et al., 2010) and STRUCTURE HARVESTER V 0.6.92 (Earl and vonHoldt, 2011).
Comments
U.S. government work.