Collection and characterization of wild species of Phaseolus (Fabaceae) in northeastern Mexico for ex situ conservation

Abstract

Background and aims–The northeastern region of Mexico is recognized for its diversity of wild species of Phaseolus (Fabaceae). However, seed samples for species characterization and ex situ conservation are scarce. This study aimed to (1) determine the growing sites of wild species of Phaseolus in northeastern Mexico, (2) collect seed samples for ex situ conservation, and (3) characterize morphologically the species found in the region. Methods–During 2010–2013, explorations were undertaken in sixteen municipalities in the states of Nuevo Leon and Tamaulipas. Each growing site was geo-referenced, and soil and vegetation characteristics were registered. Seed samples and wild bean plants at flowering stage were collected for taxonomic identification and conservation. Key results–Eleven wild species were found: Phaseolus neglectus Herm., P. leptostachyus Benth. var. leptostachyus, P. pedicellatus Benth., P. altimontanus Freytag and Debouck, P. albiflorus Freytag and Debouck, P. novoleonensis Debouck, P. maculatifolius Freytag and Debouck, P. zimapanensis A. Delgado, P. vulgaris L., P. coccineus L. subsp. coccineus var. splendens Freytag, and P. glabellus Piper. Phaseolus vulgaris exhibited the greatest morphological variation.