The evolution and phylogenetic placement of invasive Australian Acacia species

Abstract

Aim Acacia is the largest genus of plants in Australia with over 1000 species. A subset of these species is invasive in many parts of the world including Africa, the Americas, Europe, the Middle East, Asia and the Pacific region. We investigate the phylogenetic relationships of the invasive species in relation to the genus as a whole. This will provide a framework for studying the evolution of traits that make Acacia species such successful invaders and could assist in screening other species for invasive potential. Location Australia and global. Methods We sequenced four plastid and two nuclear DNA regions for 110 Australian Acacia species, including 16 species that have large invasive ranges outside Australia. A Bayesian phylogenetic tree was generated to define the major lineages of Acacia and to determine the phylogenetic placement of the invasive species. Results Invasive Acacia species do not form a monophyletic group but do form small clusters throughout the phylogeny. There are no taxonomic characters that uniquely describe the invasive Acacia species. Main conclusions The legume subfamily Mimosoideae has a high percentage of invasive species and the Australian Acacia species have the highest rate of all the legumes. There is some evidence of phylogenetic clumping of invasive species of Acacia in the limited sampling presented here. This phylogeny provides a framework for further testing of the evolution of traits associated with invasiveness in Acacia.

Phylogenetic measures of biodiversity and neo- and paleo-endemism in Australian Acacia

“…Six regions were amplified and sequenced, which included four plastid: psbA-trnH intergenic spacer, trnL-F intron and intergenic spacer, rpl32-trnL intergenic spacer, and a portion of the matK intron, and two nuclear: ETS and ITS. Details of the procedures can be found in Miller et al 38 All DNA sequences are deposited in Genbank; accession codes for sequences newly generated for this study are provided in the Accession codes section below (see also Supplementary Table 1).…”

Genetic diversity and differentiation of invasive <i>Acacia longifolia</i> in Portugal

“…Many molecular markers have been used in population and phylogenetic studies in acacias, including inter-simple sequence repeats (ISSRs), simple sequence repeats (SSRs or microsatellites), chloroplastidial DNA and internal and external transcribed spacers (ITS and ETS respectively) (Thompson et al, 2012(Thompson et al, , 2015Omondi et al, 2010Omondi et al, , 2016Harris et al, 2012;Miller et al, 2011;Le Roux et al, 2011Fredua-Agyeman et al, 2008;Mulumba et al, 2012;Josiah et al, 2008;Ndlovu et al, 2013;Murphy et al, 2010;Brown et al, , 2012. Furthermore, several SSRs markers have been developed for Acacia species, such as A. atkinsiana (Levy et al, 2014), A. brevispica (Otero-Arnaiz, 2005.…”

Rapid Identification of Acacia Species With Potential Salt Tolerance by Using Nuclear Ribosomal DNA Markers

“…In this study, A. victoriae is found to be sister to A. synchronicia, and in turn is placed in a larger clade with A. chartacea, A. ryaniana and A. alexandri. This strongly supported clade (PP = 0.999) has been resolved in previous reports (Ariati, Murphy, Udovicic, & Ladiges, 2006;Murphy et al, 2010;Miller et al, 2011;Brown et al, 2012), but the salinity tolerance of these species has not been assessed.…”

“…The consistency index was 0.146 and retention index was 0.695. Incorporation of the new dataset showed that some of the species fall into previously recognised clades (Murphy et al, 2010;Miller et al, 2011;Brown et al, 2012), e.g., the A. aulacocarpa group, A. auriculiformis group, and the A. victoriae and A. pyrifolia group (Figure 2). The tree is displayed using Fig Tree (Rambaut and Drummond, 2008), with data from Bayesian analysis of 178 Acacia species.…”

“…Therefore, clarifying molecular phylogenetic relationships can aid in selecting candidate species for a particular trait. Miller, Murphy, Brown, Richardson, and González-Orozco (2011) used plastid and nuclear rDNA data to test for invasiveness of species across a broad framework of 110 acacias. Although the invasive species did not form a monophyletic group, some evidence for phylogenetic grouping of invasive species was found.…”