Resumen

VILLARREAL-VILLAGRAN, V. H. et al. Phylogenetic relationships of Phaseolus species from Mexico based on chloroplastic DNA markers. Polibotánica [online]. 2022, n.53, pp.35-51.  Epub 04-Abr-2022. ISSN 1405-2768.  https://doi.org/10.18387/polibotanica.53.3.

The Phaseolus genus is native to Mexico; at least 31 of the 81 species known and distributed throughout America are endemic to the country. Phylogenetic studies in Phaseolus must include known species and new species that continue to be discovered. In this work, the phylogenetic relationships of 34 Phaseolus accessions collected in Mexico were analyzed, which included 19 species and two subspecies of P. coccineus; three species (P. albiviolaceus, P. maculatifolius and P. rotundatus) had not been included in a phylogeny. As an external group, an accession of Vigna radiata was included. Five non-coding regions of chloroplast DNA (cDNA): trnT-trnL, trnL-trnF, rpl16, rpoC1-rpoC2, and rps14-psaB allowed phylogenetic reconstruction by three methods (maximum parsimony, maximum likelihood, Bayesian analysis of posterior probabilities). The results indicated that the Phaseolus genus is a monophyletic group that is subdivided into two main lineages: a first clade formed by P. pluriflorus, P. esperanzae, P. pedicellatus, P. microcarpus, P. glabellus, P. oligospermus, P. gladiolatus, P. zimapanensis, and P. albiviolaceus; and a second clade that includes P. filiformis, P. acutifolius, P. vulgaris, P. coccineus, P. macvaughii, P. leptostachyus, P. lunatus, P. maculatus, P. maculatifolius, and P. rotundatus. The topology of the subclades was in general agreement with the topology for Phaseolus recognized to date. Of the species not previously studied, P. albiviolaceus belongs to the Pedicellatus group according to its morphology, but here it was located at Tuerckheimii group; P. maculatifolius and P. rotundatus were included in the Polystachios group. The ancestral clade of the Phaseolus species showed an age of 4.95 M.a. and the diversification of the two main clades exhibited similar age (3.8 M.a). The divergence between P. albiviolaceus and P. zimapanensis was 0.07 M.a. while between P. rotundatus and P. maculatifolius it was 0.31 M.a.

Palabras llave : Chloroplast DNA sequencing; phylogenetic relationships; germplasm collection; wild beans.