Species interactions and plant polyploidy

Abstract

Polyploidy is a common mode of speciation that can have far-reaching consequences for plant ecology and evolution. Because polyploidy can induce an array of phenotypic changes, there can be cascading effects on interactions with other species. These interactions, in turn, can have reciprocal effects on polyploid plants, potentially impacting their establishment and persistence. Although there is a wealth of information on the genetic and phenotypic effects of polyploidy, the study of species interactions in polyploid plants remains a comparatively young field. Here we reviewed the available evidence for how polyploidy may impact many types of species interactions that range from mutualism to antagonism. Specifically, we focused on three main questions: (1) Does polyploidy directly cause the formation of novel interactions not experienced by diploids, or does it create an opportunity for natural selection to then form novel interactions? (2) Does polyploidy cause consistent, predictable changes in species interactions vs. the evolution of idiosyncratic differences? (3) Does polyploidy lead to greater evolvability in species interactions? From the scarce evidence available, we found that novel interactions are rare but that polyploidy can induce changes in pollinator, herbivore, and pathogen interactions. Although further tests are needed, it is likely that selection following whole-genome duplication is important in all types of species interaction and that there are circumstances in which polyploidy can enhance the evolvability of interactions with other species.

Different Patterns of Ecological Divergence Between Two Tetraploids and Their Diploid Counterpart in a Parapatric Linear Coastal Distribution Polyploid Complex

“…maritima. Ultimately, each cytotype and variety probably has unique responses to the abiotic environment and to biotic interactions (Segraves and Anneberg, 2016), having clearly separate ranges that support the idea that they work as different functional units of biodiversity (Ramsey and Ramsey, 2014;Laport and Ng, 2017). Despite traditional reluctance to incorporate intraspecific ploidy differences into taxonomic decisions, particularly when no striking morphological differences are exhibited, as is frequent in autopolyploids (Soltis et al, 2007), our results support the recognition of diverse biodiversity units both between cytotypes and within the tetraploid cytotype in the J. maritima complex.…”

Polyploid plants have faster rates of multivariate niche differentiation than their diploid relatives

“…This type of abrupt, genotype independent change of ecological niche may explain some of the divergence in ecological niche observed in our analyses. Other physiological differences associated with WGD include changes in propagule volume (Barrington et al ), size and density of stomata (Sax & Sax ; Maherali et al ), resistance to drought and cold (Levin ), and secondary metabolites and phenology (Levin ; Segraves & Anneberg ). The many cases examined in our analyses provide a starting point for exploring the contribution of these potential avenues for WGD – independent of genotype – to alter plant physiology and ecological niche.…”

Autopolyploidy alters nodule‐level interactions in the legume–rhizobium mutualism

“…Polyploidy is a major genetic driver of ecological and evolutionary processes in plants, yet little is known about its effects on biotic interactions (Segraves and Anneberg, 2016). In this study, we explored how the legume-rhizobium mutualism is directly impacted by plant polyploidy, thereby isolating the effects of polyploidy on species interactions apart from other evolutionary changes that occurred after the polyploidy event.…”

“…Polyploidy (i.e., the possession of more than two complete sets of chromosomes from one or more genetic donors) is a key driver of ecological and evolutionary processes in plants (Soltis and Soltis, ). Although the effects of polyploidy on plant genotypes, phenotypes, and abiotic interactions are fairly well understood (Levin, ; Soltis and Soltis, ), only a handful of studies have explored how polyploidy affects biotic interactions (Powell and Doyle, ; Segraves and Anneberg, ). The legume–rhizobium interaction is a model nutrient acquisition mutualism that regulates global nutrient cycles, supplies nitrogen (N) to natural and agricultural environments, and contributes to the widespread distribution of legume taxa (Fabaceae; Daehler, ; Herridge et al., ; Sprent, ; Vitousek et al., ).…”