Physiology of a plant invasion

Abstract

Meyerson L. A. (2019) Physiology of a plant invasion: biomass production, growth and tissue chemistry of invasive and native Phragmites australis populations. -Preslia 91: 51-75.Differentiation within Phragmites australis, one of the world's most cosmopolitan and globally important wild plants, and invasions by individual lineages outside of their native ranges is attracting the interest of scientists worldwide. We compared the physiological performance of 89 populations representing distinct genotypes from six phylogeographic groups from Australia, Europe, North America (two groups including native and invasive populations introduced from Europe), South Africa and Far East in a common garden experiment. We show that the populations cluster into two distinct groups: one that includes populations from Europe and Far East together with the North American invasive, and the second the North American native populations with those from Australia and South Africa. Populations within the former group exhibited superior performance in the following traits: they were more vigorous in terms of higher shoot number per pot, greater belowground biomass, longer rhizomes, had greater specific leaf area (SLA), higher N and P concentrations in tissues, and greater investment into generative reproduction. Pooled across phylogeographic groups, P. australis has higher values of maximal photosynthesis (Amax), higher N and P concentrations in tissues, and greater SLA than most vascular plants, represented by the GLOPNET dataset. Whether due to a weak environmental match or genetic differences, the results indicate that invasion by Australian and African populations in the Northern Hemisphere seems unlikely at present. However, it is not possible to exclude the invasion of genotypes of European origin into Southern Hemisphere or other temperate regions. K e y w o r d s: below-and aboveground biomass,

Competition among native and invasive Phragmites australis populations: An experimental test of the effects of invasion status, genome size, and ploidy level

“…The fact that European native populations are such a strong competitor against North American native plants indicates that competition might have been involved in the initial invasion centuries ago, following introduction, and in facilitating the initial space preemption in sites that European plants reached by long-distance dispersal. Here, it needs to be noted that the European native populations have an even smaller genome than North American invasive, as shown in the previous common-garden experiment (Pyšek et al, 2019 hypothesized about a possible postintroduction shift in traits, providing European invaders with advantages at different stages of the invasion process, and interpreted these findings with respect to introductions of populations with different genome sizes. According to these authors, among the European populations introduced to North America, those that established and spread likely had on average slightly bigger genomes than those that might have been filtered out following introduction from the native European range.…”

“…The vast majority of such studies search for the determinants of invasiveness by comparing different species, focusing on regional floras (e.g., Pyšek et al, 2012;Inderjit et al, 2018) or taxonomically narrowed study systems (e.g., Gallagher et al, 2011;Grotkopp, Rejmánek, & Rost, 2002). Recently, it is increasingly recognized that addressing invasions at the intraspecific level can provide novel insights into mechanisms underlying plant invasiveness, by comparing particular invading populations and addressing more subtle differences in their performance when trait differences associated with species level are held constant (Cronin, Bhattarai, Allen, & Meyerson, 2015;Pyšek et al, 2019). One system that provides opportunities to focus on organizational levels below the species rank, such as subspecies, populations, or individual genotypes, is a dominant species of wetlands all over the world Phragmites australis (common reed, Poaceae; Meyerson & Cronin, 2013;Meyerson, Lambert, & Saltonstall, 2010;Packer, Meyerson, Skálová, Pyšek, & Kueffer, 2017).…”

“…(b) Invasive populations differ from native populations in a number of growth, physiological, and reproductive traits (Pyšek et al, 2019) that can be related to a small genome, an underlying characteristic separating both groups (Pyšek et al, 2018). (c) Based on this, we hypothesized that small genomes constitute a key advantage in a direct competition between invasive and native populations that is manifested through traits associated with genome size (Suda et al, 2015).…”

Nitrogen immobilization may reduce invasibility of nutrient enriched plant community invaded by Phragmites australis

“…Study species. Phragmites australis is a cosmopolitan and successional species that is distributed all over the world (except Antarctica), and still it remains unclear about its originality in many regions of the earth 21 . It has been considered as a weedy and invasive population in North America, Australia, and Madagascar [65][66][67] .…”

“…Physiological characteristics of Phragmites including high rates of reproduction, well-developed aerenchyma and rhizosphere facilitate colonization, and dense canopies related to their high productivity can inhibit germination and growth of neighbour plant species [18][19][20] . The tissue chemistry of Phragmites and its extensive production alters nutrient pools 21 and availability in soils 16,18 . Together with its negative effects on ecology, Phragmites can impose considerable financial loss 22 .…”