Phylogenomics and biogeography of Guadua: Insights into a neotropical woody bamboo genus.

Abstract

Premise: The genus Guadua includes some of the largest bamboo species in the neotropics, with certain species of significant economic importance and used since pre-Hispanic times to build houses using the traditional bajareque technique. Guadua species are distributed from Mexico to South America. The potential monophyly of this genus has been suggested based on plastid markers and limited sampling. Here we included more species and nuclear data to study the morphological classification of Guadua and to reconstruct its ancestral area distribution.

Methods: Samples were collected for 16 Guadua taxa (13 species) to use nuclear single nucleotide polymorphisms (SNPs) derived from restriction-site associated DNA sequencing (RADSeq) data to construct a phylogenetic hypothesis using maximum likelihood and coalescent methods. We estimated divergence times using the RelTime method and reconstructed ancestral geographic areas using S-DEC analysis.

Results: The SNP data supported the monophyly of the genus Guadua and the existence of two distinct clades, Amplexifolia and Angustifolia. The origin of Guadua was estimated as approximately 10.47 million years ago in Mesoamerica. The biogeographic distribution of Guadua can likely be explained by a combination of dispersal and vicariant events.

Conclusions: Our study sheds new light on the phylogenetic relationships within Guadua and on its evolutionary history and biogeography, enhancing our understanding of its diversification and distribution across various biogeographic regions.