Interspecific variation in ploidy as a key plant trait outlining local extinction risks and community patterns in fragmented landscapes

Abstract

Polyploidy is associated with a plethora of phenotypic and genetic changes yielding transformative effects on species' life‐history and ecology. These biological attributes can contribute to the success of species on ecological timescales, as observed in the invasion success or rapid environmental and climatic adaptation of polyploids. However, to date there has been a distinct lack of empirical evidence linking species' local extinction risk, species distributions and community structure in fragmented landscapes with interspecific variation in ploidy. We aimed to investigate the relationship between levels of habitat fragmentation and patterns in both diversity and the frequency of species with different ploidy levels. We included additional persistence‐ and dispersal related life‐history traits, to establish the relative importance of ploidy in determining species richness and frequencies following habitat fragmentation. We therefore collected plant community presence‐absence data and landscape data from grassland fragments from south‐central Sweden. Community‐level analysis uncovered that interspecific variation in ploidy proved the strongest predictor of plant community species richness and turn‐over across grassland fragments. Local extinction risk decreased as ploidy increased, with diploids most prone to local extinction. In the species‐level analysis, ploidy outweighed the combined explanatory power of commonly used life‐history traits such as clonality, dispersal mechanism and mating system; key predictors of plant species distributions across fragmented landscapes. Ploidy appears to capture parallel variation in a series of advantageous genetic and life‐history mechanisms which operate on ecological timescales, emerging as the strongest predictor of local extinction risk even after accounting for variation in other crucial life‐history traits. Our results therefore highlight the importance of genomic traits such as ploidy and total chromosome number as valuable factors explaining and predicting local extinction risk in fragmented landscapes. A http://onlinelibrary.wiley.com/doi/10.1111/1365-2435.fec13127/suppinfo is available for this article.

Ecotypic differentiation of a circumpolar Arctic-alpine species at mid-latitudes: variations in the ploidy level and reproductive system of Vaccinium vitis-idaea

“…First, tetraploids may have tolerance to isolated situation in terms of population persistence owing to the higher genetic diversity more than diploids ( Abeli 2014 ). Higher level of heterozygosity is maintained in tetraploids even in isolated small populations ( Rosche et al 2016 ), resulting in lower risk of extinction ( Plue et al 2018 ). In the present study, some tetraploid populations (TES, EN1, TEI, KAM, HA) were isolated within small area (<50 m in length), and they were often composed of small number of clones.…”

Are buffalograss (Buchloë dactyloides) cytotypes spatially and ecologically differentiated?

“…1B). Diploid cytotypes are viewed as generally occupying narrower and more peripheral distributions relative to higher cytotypes in autopolypoid series (Stebbins, 1950) and have been shown to be more susceptible to local extinction in fragmented landscapes (Plue et al, 2018). This is potentially due in part to the one-way nature of autopolyploid series, with diploids giving rise to tetraploids, tetraploids giving rise to hexaploids, and so on.…”

Global-scale drivers of ploidy state in aquatic macrophytes

“…These stressors may be associated with latitude and other spatial, environmental, and landscape-level drivers, both natural and human-related, known to influence the macroecology of these plants (e.g., Murphy et al, 2019Alahuhta et al, 2020 in press). If, as has been asserted, polyploidy can be a response to habitat loss and isolation, then high levels of ploidy may be a strategy of plant species which enhances their survival in human-impacted landscapes (Plue et al, 2018), as well as in natural habitats experiencing strong environmental stress or disturbance pressures (e.g., Chambers et al, 1999;Ulum et al 2020). Despite the increasing evidence that ploidy is a factor of importance for environmental adaptation, relatively few studies have to date addressed the ecological drivers of change in ploidy state for aquatic plants (Šmarda et al, 2013;Soltis et al, 2016;Segraves, 2017).…”