Year: 2020
Type: article
Abstract: Polyploidy is a key driver of ecological and evolutionary processes in plants, yet little is known about its effects on biotic interactions. This gap in knowledge is especially profound for nutrient acquisition mutualisms, despite the fact that they regulate global nutrient cycles and structure ecosystems. Generalism in mutualistic interactions depends on the range of potential partners (niche breadth), the benefits obtained and ability to maintain benefits across a variety of partners (fitness plasticity). Here, we determine how each of these is influenced by polyploidy in the legume-rhizobium mutualism. We inoculated a broad geographic sample of natural diploid and autotetraploid alfalfa (Medicago sativa) lineages with a diverse panel of Sinorhizobium bacterial symbionts. To analyze the extent and mechanism of generalism, we measured host growth benefits and functional traits. Autotetraploid plants obtained greater fitness enhancement from mutualistic interactions and were better able to maintain this across diverse rhizobial partners (i.e. low plasticity in fitness) relative to diploids. These benefits were not attributed to increases in niche breadth, but instead reflect increased rewards from investment in the mutualism. Polyploid plants displayed greater generalization in bacterial mutualisms relative to diploids, illustrating another axis of advantage for polyploids over diploids.
Source: New Phytologist
DOI: 10.1111/nph.16574
Institutions: University of Pittsburgh, University of California, Riverside
Language: English
Subfield: Plant Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: bronze
Awards: CAREER: EVOLUTION OF HOST CONTROL OVER SYMBIOSIS, DYSBIOSIS IN ANTHROPOGENIC LANDSCAPES, Graduate Research Fellowship Program (GRFP), Dimensions US-China: Collaborative Research: An integrated understanding of how polyploidy generates biodiversity, Dimensions: Collaborative Research: Elucidating the drivers of mutualism variation in host-symbiont metapopulations, The role of post-pollination interactions in structuring co-flowering plant communities
OpenAlex ID: W3014234173