Phenotyping the genetic diversity of wild agave species that coexist in the same spatial region

Abstract

Phenotypic characteristics are important to identify species and provide valuable information for the uses in plant breeding. The aim of this study was to characterize through morphological traits the genetic diversity of the Agave genus under wild and semi-wild culture conditions in Maguey Largo region in Oaxaca, Mexico. Through field trips, eleven morphological characteristics of the Agave species were recorded. Principal component analysis (PCA), phylogenetic trees, and correlation analyses, were performed. Seven wild species were identified: Agave potatorum Zucc., A. seemanniana, A. nussaviorum subsp. nussaviorum, A. angustifolia Haw., A. marmorata Roezl., A. karwinskii Zucc. and A. americana var. Americana. Also, a semiwild unclassified specie Agave sp. was found. The values of the first four principal components in the PCA explain more than 89% of the total morphological variance. The dendrogram of the agglomerative hierarchical clustering (AHC) shown a high similarity between the species and divide them in two main cluster with one unassociated specie (A. karwinskii Miahuatlán shape). Following the different analyses done, we observed a very close relationship between A. potatorum and A. nussaviorum, and dissociated from A. seemanniana, which are belonging to the "Tobala" complex and never described before. The results obtained in this work suggest a great genetic diversity expressed in a wide morphological variety of agaves in Oaxaca; which can be used in futures molecular studies.