CRUZ et al. 2015 (Conference Paper) Cryptanthus

Molecular infrageneric relationships and genome size evolution in Cryptanthus

Author(s):—Geyner CRUZ, Daniele Silvestro, Elton Leme, Georg Zizka, Katharina Shulte, José Campos, Lyderson Viccini & Ana Benko-Iseppon in Benko-Iseppon, A.M.; Alves, M. & Louzada, R. (2015) An overview and abstracts of the First World Congress on Bromeliaceae Evolution. Rodriguésia 66(2): A1-A66.

Publication:— (2015).

Abstract:—The genus Cryptanthus is a distinct group within Bromeliaceae, comprising about 67 species endemic to easternBrazil occurring in the Atlantic Forest, restinga, campos rupestres and caatinga. Due to high endemism, narrowgeographic distribution, and loss of natural habitats, the genus presents many endangered species. Here we presentthe first molecular phylogeny of Cryptanthus based on AFLP analysis of 48 species together with genome size datain a phylogenetic framework. For the phylogenetic reconstruction the AFLP banding pattern was scored manually,considering presence or absence of each band at a particular position. Phylogenetic trees were generated using Maximum Parsimony (MP), Maximum Likelihood (ML) and Bayesian Inference. The genome sizes were estimated byflow cytometry and compared with a selected phylogenetic tree. In the phylogenetic tree generated, the subgeneraCryptanthus and Hoplocryptanthus appeared as non-monophyletic. The proposed morphological groups of the genuspresented homoplasic characters, with the exception of the inconclusive group Lacerdae. Phylogenetic relationships among the species remained ambiguous due to low resolution. Furthermore, some of the clades that received goodsupport ? mainly in the subgenus Cryptanthus ? did not follow the morphological species delimitation. Atlantic Forestand campos rupestres showed a defined pattern of occupation within subgenus Hoplocryptanthus, which may alsobe evidence of the polyphyletic condition of this lineage at the habitat level. Regarding genome size, the 1C DNAvalues differed up to 2.13-fold among species (varying from 0.38 pg up to 0.83 pg). The analyses of the genome sizedistribution on the Cryptanthus phylogenetic tree matched the two defined major lineages. Therefore, there was asignificant difference in DNA content between the subgenera Cryptanthus and Hoplocryptanthus. This study provided the first insights on the molecular phylogenetic relationships of the genus Cryptanthus. Our phylogenetic reconstructionindicated that both subgenera Cryptanthus and Hoplocryptanthus form a polyphyletic group. Several nodes within the genus Cryptanthus remained unresolved maybe because they concern recent evolution trends within Bromeliaceae. Moreover, the data at hand showed no clear phylogenetic position of the group Lacerdae and it is necessary to improvethe phylogenetic resolution to get a more conclusive answer about the position of this group. Regarding genome size,our findings suggest that various evolutionary forces and processes have shaped the observed genome size variation.Nevertheless, apparently the phylogenetic relationships were the most determinant factors of the observed divergencein genome size at the basal nodes.

Keywords:—Bromelioideae; Hoplocryptanthus; Nuclear DNA Content.