Phylogeny of Pelargonium (Geraniaceae) based on DNA sequences from three genomes

Abstract

Phylogenetic hypotheses for the largely South African genus Pelargonium L'Hér. (Geraniaceae) were derived based on DNA sequence data from nuclear, chloroplast and mitochondrial encoded regions. The datasets were unequally represented and comprised cpDNA trnL­F sequences for 152 taxa, nrDNA ITS sequences for 55 taxa, and mtDNA nad 1 b/c exons for 51 taxa. Phylogenetic hypotheses derived from the separate three datasets were overall congruent. A single hypothesis synthesising the information in the three datasets was constructed following a total evidence approach and implementing dataset specific stepmatrices in order to correct for substitution biases. Pelargonium was found to consist of five main clades, some with contrasting evolutionary patterns with respect to biogeographic distributions, dispersal capacity, pollination biology and karyological diversification. The five main clades are structured in two (subgeneric) clades that correlate with chromosome size. One of these clades includes a "winter rainfall clade" containing more than 70% of all currently described Pelargonium species, and all restricted to the South African Cape winter rainfall region. Apart from (woody) shrubs and small herbaceous rosette subshrubs, this clade comprises a large "xerophytic" clade including geophytes, stem and leaf succulents, harbouring in total almost half of the genus. This clade is considered to be the result of in situ proliferation, possibly in response to late­Miocene and Pliocene aridification events. Nested within it is a radiation comprising c. 80 species from the geophytic Pelargonium section Hoarea, all characterised by the possession of (a series of) tunicate tubers.

Population and phylogenomic decomposition via genotyping‐by‐sequencing in Australian Pelargonium

“…Previous phylogenetic studies of the genus Pelargonium using limited molecular markers have been unsuccessful in resolving species relationships among Australian members of the genus (Bakker et al . , , , ). Our results illustrate how a broad bioinformatic approach for both population and phylogenomic data, combined with traditional morphometric data and breeding system studies, can be used to delimit species boundaries and determine character convergence and polymorphism (Emerson et al .…”

Shifts in Climate Foster Exceptional Opportunities for Species Radiation: The Case of South African Geraniums

“…Rate diversification and comparative analyses were based on Bakker et al's 50% majority rule Bayesian consensus tree [26]. This phylogenetic hypothesis is based on four data partitions: cpDNA trn L-F, nrDNA ITS, mtDNA nad 1b/c, and 30 recoded indels inferred from the plastid partition [22], [26].…”

“…This phylogenetic hypothesis is based on four data partitions: cpDNA trn L-F, nrDNA ITS, mtDNA nad 1b/c, and 30 recoded indels inferred from the plastid partition [22], [26]. For the analysis of niche evolution, we pruned this phylogenetic tree (originally containing 150 species) to include only the 112 species with distributional information; distribution was obtained from digital databases [27], [28], taxonomic monographs and our collection records.…”

Fertilization and Colors of Plastic Mulch Affect Biomass and Essential Oil of Sweet-Scented Geranium

“…The Pelargonium (Geraniaceae) genus contains around 280 herbaceous, shrub, and subshrub species, including annuals and perennials that typically originated from southern Africa [1]. Pelargonium graveolens L'Hér is one of the most important species in this genus and is an aromatic shrub species that can reach up to 1.3 m in height.…”