skip to main content

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


  • NSF Public Access
  • Search Results
  • Do water and soil nutrient scarcities differentially impact the performance of diploid and tetraploid Solidago gigantea (Giant Goldenrod, Asteraceae)?
Title: Do water and soil nutrient scarcities differentially impact the performance of diploid and tetraploid Solidago gigantea (Giant Goldenrod, Asteraceae)?
ABSTRACT

Plants require water and nutrients for survival, although the effects of their availabilities on plant fitness differ amongst species. Genome size variation, within and across species, is suspected to influence plant water and nutrient requirements, but little is known about how variations in these resources concurrently affect plant fitness based on genome size. We examined how genome size variation between autopolyploid cytotypes influences plant morphological and physiological traits, and whether cytotype‐specific trait responses differ based on water and/or nutrient availability.

Diploid and autotetraploidSolidago gigantea(Giant Goldenrod) were grown in a greenhouse under four soil water:N+P treatments (L:L, L:H, H:L, H:H), and stomata characteristics (size, density), growth (above‐ and belowground biomass, R/S), and physiological (Anet,E,WUE) responses were measured.

Resource availabilities and cytotype identity influenced some plant responses but their effects were independent of each other. Plants grown in high‐water and nutrient treatments were larger, plants grown in low‐water or high‐nutrient treatments had higherWUEbut lowerE, andAnetandErates decreased as plants aged. Autotetraploids also had larger and fewer stomata, higher biomass and largerAnetthan diploids.

Nutrient and water availability could influence intra‐ and interspecific competitive outcomes. AlthoughS. giganteacytotypes were not differentially affected by resource treatments, genome size may influence cytogeographic range patterning and population establishment likelihood. For instance, the larger size of autotetraploidS. giganteamight render them more competitive for resources and niche space than diploids.

  more » « less
Award ID(s):
1941309
PAR ID:
10372630
Author(s) / Creator(s):
 ;  ;
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Plant Biology
Volume:
24
Issue:
6
ISSN:
1435-8603
Page Range / eLocation ID:
p. 1031-1042
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ( , American Journal of Botany)
    Abstract Premise

    Increased genome‐material costs of N and P atoms inherent to organisms with larger genomes have been proposed to limit growth under nutrient scarcities and to promote growth under nutrient enrichments. Such responsiveness may reflect a nutrient‐dependent diploid versus polyploid advantage that could have vast ecological and evolutionary implications, but direct evidence that material costs increase with ploidy level and/or influence cytotype‐dependent growth, metabolic, and/or resource‐use trade‐offs is limited.

     Methods

    We grew diploid, autotetraploid, and autohexaploidSolidago giganteaplants with one of four ambient or enriched N:P ratios and measured traits related to material costs, primary and secondary metabolism, and resource‐use.

     Results

    Relative to diploids, polyploids invested more N and P into cells, and tetraploids grew more with N enrichments, suggesting that material costs increase with ploidy level. Polyploids also generally exhibited strategies that could minimize material‐cost constraints over both long (reduced monoploid genome size) and short (more extreme transcriptome downsizing, reduced photosynthesis rates and terpene concentrations, enhanced N‐use efficiencies) evolutionary time periods. Furthermore, polyploids had lower transpiration rates but higher water‐use efficiencies than diploids, both of which were more pronounced under nutrient‐limiting conditions.

     Conclusions

    N and P material costs increase with ploidy level, but material‐cost constraints might be lessened by resource allocation/investment mechanisms that can also alter ecological dynamics and selection. Our results enhance mechanistic understanding of how global increases in nutrients might provide a release from material‐cost constraints in polyploids that could impact ploidy (or genome‐size)‐specific performances, cytogeographic patterning, and multispecies community structuring.

     
    more » « less
  2. ; ; ; ( , New Phytologist)
    Summary

    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 ofSinorhizobiumbacterial 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.

     
    more » « less
  3. ; ; ( , Ecological Entomology)
    Abstract

    Host plant shifts are central to diversification in insect herbivores. Many mechanisms can cause host shifts in insects, but one relatively unexplored mechanism is whole‐genome duplication (WGD) in the host plant. WGD, or polyploidy, is common in plants and causes spontaneous changes in physiology, morphology, and palatability that could impact the ability of herbivores to feed and develop on newly formed polyploids (neopolyploids).

    Here the authors tested if WGD affected the preference and performance of the specialist aphid,Acyrthosiphon pisum(pea aphids). Pea aphids seasonally form specialised lineages or ‘host forms’ on many host plant species including alfalfa and red clover. Aphid host forms on alfalfa and red clover naturally exist on different cytotypes of their respective hosts, with red clover aphids feeding on diploid clover and alfalfa aphids feeding on tetraploid alfalfa. Therefore, the authors predicted that these host forms would have a higher preference for and performance on their respective natal host cytotype.

    Neither host form exhibited a preference for a particular cytotype, but there were modest changes in aphid performance based on host cytotype. Specifically, aphids specialised to red clover had higher fecundity on diploid red clover than on neotetraploid red clover. Together, these results showed that both host forms were able to recognise and accept different cytotypes of the two host species, but only one host form experienced trade‐offs in performance when feeding on neotetraploids. These results suggest that WGD may act as a mechanism of host expansion in pea aphids as plants speciate via WGD.

     
    more » « less
  4. ; ( , Journal of Ecology)
    Abstract

    Temporally heterogeneous environments may drive rapid and continuous plastic responses, leading to highly variable plasticity in traits. However, direct experimental evidence for such meta‐plasticity due to environmental heterogeneity is rare.

    Our objective was to investigate the effects of early experience with temporally heterogeneous water availability on the subsequent plasticity of plant species in response to water conditions.

    We subjected eight plant species from three habitats, four exotic and four native to North America, to initial exposure to either a first round of alternating drought and inundation treatment (Ehet, temporally heterogeneous experience) or a consistently moderate water supply (Ehom, homogeneous experience), and to a second round of drought, moderate watering or inundation treatments. Afterwards the performance in a series of traits of these species, after the first and second rounds of treatments, was measured.

    Compared withEhom,Ehetincreased final mean total mass of all species considered together but did not affect mean mortality.Ehetrelative toEhom, decreased the initial total mass of native species as a group, but increased the mass of exotic species or species from hydric habitats;Ehetalso increased the late growth of natives, but did not for exotics, and increased the late growth of mesic species more than xeric and hydric species.

    Our results suggest that previous exposure to temporal heterogeneity in water supply may be not beneficial immediately, but can be beneficial for plant growth and response to water stress later in a plant's lifetime. Heterogeneous experiences may not necessarily enhance the degree of plasticity but may improve the expression of plasticity in terms of better performance later, effects of which differ for different groups of species, suggesting species‐specific strategies for dealing with fluctuating abiotic environments.

    Synthesis. Previous temporally heterogeneous experience can benefits plant growth later in life though modulating the expression of plasticity, leading to adaptive meta‐plasticity. Studies of meta‐plasticity may improve our understanding not only on the importance of variable plasticity in relation to how plants cope with environmental challenges but also on the costs versus benefits of plastic responses and its limits over the long term.

     
    more » « less
  5. ; ( , Ecological Entomology)
    Abstract

    Plant genotype, water stress and their interaction are among the factors contributing to the susceptibility of plants to herbivory. The plant's nitrogen concentration, a critical and often limiting nutrient, differs with plant genotype and water stress. Still, few studies have investigated the impact of the interaction between genotype and water stress on herbivory and plant nitrogen.

    We established a common garden in Duluth, MN, of tall goldenrod,Solidago altissima,collected from a local Minnesota site to analyse the effects of goldenrod genotype and water stress on leaf nitrogen and the preference and performance of the chrysanthemum lace bug,Corythucha marmorata.

    Lace bugs had oviposition, nymph and adult preferences among host plant genotypes, water treatments and among genotype and water treatment combinations. Nymph and adult survival and adult mass varied significantly due to plant genotype, water treatment, the interaction between plant and water treatment and the interaction of treatment with lace bug density. Oviposition preference and offspring performance were significantly positively related.

    Leaf nitrogen increased with the increasing severity of the water limitation in the absence of lace bugs. However, in the presence of lace bugs, there was no difference in nitrogen among water treatments.

    We hypothesize that lace bugs reduce leaf nitrogen concentration to a lower threshold and then move between plants until nitrogen concentration equalises among all plants.

     
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Save / Share this Record
  • Send to Email