Physiological ecology and functional traits of North American native and Eurasian introduced Phragmites australis lineages

Cuiping

et al. 2018

Ecology and Evolution

While many introduced invasive species can increase genetic diversity through multiple introductions and/or hybridization to colonize successfully in new environments, others with low genetic diversity have to persist by alternative mechanisms such as epigenetic variation. Given that Phragmites australis is a cosmopolitan reed growing in a wide range of habitats and its invasion history, especially in North America, has been relatively well studied, it provides an ideal system for studying the role and relationship of genetic and epigenetic variation in biological invasions. We used amplified fragment length polymorphism (AFLP) and methylation‐sensitive (MS) AFLP methods to evaluate genetic and epigenetic diversity and structure in groups of the common reed across its range in the world. Evidence from analysis of molecular variance (AMOVA) based on AFLP and MS‐AFLP data supported the previous conclusion that the invasive introduced populations of P. australis in North America were from European and Mediterranean regions. In the Gulf Coast region, the introduced group harbored a high level of genetic variation relative to originating group from its native location, and it showed epigenetic diversity equal to that of the native group, if not higher, while the introduced group held lower genetic diversity than the native. In the Great Lakes region, the native group displayed very low genetic and epigenetic variation, and the introduced one showed slightly lower genetic and epigenetic diversity than the original one. Unexpectedly, AMOVA and principal component analysis did not demonstrate any epigenetic convergence between native and introduced groups before genetic convergence. Our results suggested that intertwined changes in genetic and epigenetic variation were involved in the invasion success in North America. Although our study did not provide strong evidence proving the importance of epigenetic variation prior to genetic, it implied the similar role of stable epigenetic diversity to genetic diversity in the adaptation of P. australis to local environment.

Section: Introductionmentioning

confidence: 99%

Genetic and epigenetic changes during the invasion of a cosmopolitan species (Phragmites australis)

Cuiping

et al. 2018

Ecology and Evolution

“…Further, differences in growth rate between the lineages are known to become exacerbated in response to eutrophication and elevated atmospheric CO 2 (Saltonstall and Stevenson 2007; Holdredge et al 2010; Mozdzer and Megonigal 2012; Tulbure et al 2012; Mozdzer et al 2013). Eutrophication is probably one of the primary drivers of the introduced lineage spreading rapidly in many wetland ecosystems.…”

Section: Introductionmentioning

confidence: 99%

Belowground advantages in construction cost facilitate a cryptic plant invasion

2014

Energetic costs of tissue construction were compared in two subspecies of Phragmites australis, the common reed – namely the primary native and introduced lineages in North America. Caplan et al. report that the introduced lineage has lower construction costs than the native under all environmental conditions assessed, driven mainly by its lower cost rhizomes. These results highlight the fact that belowground energetics, which are seldom investigated, can influence the performance advantages that drive many plant invasions. The authors also demonstrate that tissue construction costs in organs not typically assessed can shift with global change, suggesting that they may have increasingly important implications into the future.

Diversity and Distributions

“…Consequently, it is thought that once a new site is colonized, formation of large, dense stands is through asexual expansion (Alvarez et al, 2005;Albert et al, 2015). This is supported by studies of European populations, where clonal growth strongly influences the composition of sites and of individual stands within sites, with some very large stands comprising a single clone (Neuhaus et al, 1993;Koppitz et al, 1997;Kuhl et al, 1999;Curn et al, 2007;K riv a ckov a-Such a et al, 2007;Lambertini et al, 2008). This dynamic has also been observed in the North American subspecies (Kettenring & Mock, 2012).…”

Section: Introductionmentioning

confidence: 86%

The influence of habitat disturbance on genetic structure and reproductive strategies within stands of native and non‐native Phragmites australis (common reed)

Fant

Price

Larkin

2016

Aim A surprising finding of genetic studies of Phragmites australis is that native populations, whether in Europe or North America, are characterized by lower genetic diversity than non-native populations. What is not clear is whether higher diversity within invasive stands results from disturbance facilitating sexual reproduction or whether individuals with higher diversity have greater invasion potential.Location Upper Midwest, United States, North America.Methods To answer this question, we investigated genetic structure of native and non-native P. australis stands at multiple spatial scales and under differing levels of anthropogenic disturbance. Our goals were to assess the influence of habitat disturbance on genetic structure and determine whether patterns differed in native versus non-native stands. We also screened for hybrid genotypes, which have not been reported from this region.Results When controlling for disturbance, native and non-native P. australis exhibited relatively similar within-site genetic diversity and degrees of clonal growth, suggesting that their spread is comparably reliant on clonal versus sexual dispersal. In all cases, discrete clumps of P. australis were composed of multiple, closely related genotypes, indicating seed heads as the key dispersal units. The genetic structure of P. australis stands did not differ with disturbance; however, only non-native P. australis was found in highly disturbed anthropogenic habitats. Native P. australis stands exhibited lower genetic diversity overall, lower sexual reproduction in less disturbed sites and greater isolation by distance and differentiation among sites, which is consistent with its longer residence time in this region. We found no evidence of hybrid genotypes, despite native and non-native stands sometimes co-occurring.Main conclusions Our results suggest that invasion by non-native P. australis is sporadic, associated with disturbance and involves closely related individuals, likely derived from a single seed head. The ability of the non-native lineage to exploit a variety of anthropogenic habitats helps to explain its invasiveness.