TY - JOUR T1 - Epigenetic Inheritance across the Landscape. JF - Frontiers in genetics Y1 - 2016 A1 - Whipple,Amy V A1 - Holeski,Liza M AB - The study of epigenomic variation at the landscape-level in plants may add important insight to studies of adaptive variation. A major goal of landscape genomic studies is to identify genomic regions contributing to adaptive variation across the landscape. Heritable variation in epigenetic marks, resulting in transgenerational plasticity, can influence fitness-related traits. Epigenetic marks are influenced by the genome, the environment, and their interaction, and can be inherited independently of the genome. Thus, epigenomic variation likely influences the heritability of many adaptive traits, but the extent of this influence remains largely unknown. Here, we summarize the relevance of epigenetic inheritance to ecological and evolutionary processes, and review the literature on landscape-level patterns of epigenetic variation. Landscape-level patterns of epigenomic variation in plants generally show greater levels of isolation by distance and isolation by environment then is found for the genome, but the causes of these patterns are not yet clear. Linkage between the environment and epigenomic variation has been clearly shown within a single generation, but demonstrating transgenerational inheritance requires more complex breeding and/or experimental designs. Transgenerational epigenetic variation may alter the interpretation of landscape genomic studies that rely upon phenotypic analyses, but should have less influence on landscape genomic approaches that rely upon outlier analyses or genome-environment associations. We suggest that multi-generation common garden experiments conducted across multiple environments will allow researchers to understand which parts of the epigenome are inherited, as well as to parse out the relative contribution of heritable epigenetic variation to the phenotype. VL - 7 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=27826318&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. ER - TY - JOUR T1 - Tree genotype influences ectomycorrhizal fungal community structure: Ecological and evolutionary implications JF - FUNGAL ECOLOGY Y1 - 2016 A1 - Lamit,LJ A1 - LM Holeski A1 - L Flores-Renteria A1 - TG Whitham A1 - CA Gehring AB - Although the eco-evolutionary dynamics of multicellular organisms are intertwined with the microorganisms that colonize them, there is only a rudimentary understanding of how a host's genotype influences its microbiome. We utilize Populus angustifolia to test whether communities of essential symbionts, ectomycorrhizal fungi (EMF), vary among host genotypes. Further, we test whether EMF communities covary among tree genotypes with the chemistry of senescent leaves and aboveground biomass, traits important to tree fitness, and carbon and nutrient cycling. We found: 1) EMF composition, colonization and the Basidiomycota to Ascomycota ratio varied among tree genotypes (broad-sense heritability=0.10鈥0.25). 2) EMF composition did not covary among genotypes with aboveground biomass but it did covary with senescent leaf chemistry ( rho =0.29), primarily due to a single genotype. These findings demonstrate a link between tree genotype and EMF communities, which has implications for fungal diversity, host-symbiont interactions and aboveground-belowground linkages in ecological and evolutionary contexts. VL - 24 UR - http://www.sciencedirect.com/science/article/pii/S1754504816300563 ER - TY - JOUR T1 - Tree genotype influences ectomycorrhizal fungal community structure: ecological and evolutionary implications. JF - Fungal Ecology Y1 - 2016 A1 - L.J. Lamit A1 - L. M. Holeski A1 - L. Flores-Rentería A1 - T. G. Whitham A1 - C. A. Gehring KW - Ectomycorrhizal fungi KW - Genotype Heritability KW - Populus KW - Senescent leaf chemistry AB -

Although the eco-evolutionary dynamics of multicellular organisms are intertwined with the microorganisms that colonize them, there is only a rudimentary understanding of how a host's genotype influences its microbiome. We utilize Populus angustifolia to test whether communities of essential symbionts, ectomycorrhizal fungi (EMF), vary among host genotypes. Further, we test whether EMF communities covary among tree genotypes with the chemistry of senescent leaves and aboveground biomass, traits important to tree fitness, and carbon and nutrient cycling. We found: 1) EMF composition, colonization and the Basidiomycota to Ascomycota ratio varied among tree genotypes (broad-sense heritability = 0.10–0.25). 2) EMF composition did not covary among genotypes with aboveground biomass but it did covary with senescent leaf chemistry (rho = 0.29), primarily due to a single genotype. These findings demonstrate a link between tree genotype and EMF communities, which has implications for fungal diversity, host-symbiont interactions and aboveground-belowground linkages in ecological and evolutionary contexts.

VL - 24 UR - https://www.sciencedirect.com/science/article/pii/S1754504816300563 IS - Part B ER - TY - JOUR T1 - Patterns of phytochemical variation in Mimulus guttatus (yellow monkeyflower). JF - Journal of chemical ecology Y1 - 2013 A1 - Holeski,Liza M A1 - Keefover-Ring,Ken A1 - Bowers,M Deane A1 - Harnenz,Zoe T A1 - Lindroth,Richard L KW - Animals KW - Biological Evolution KW - Butterflies KW - Genetic Variation KW - Glucosides KW - Glycosides KW - Herbivory KW - Larva KW - Mimulus KW - Phenols KW - Phenotype KW - Pheromones KW - Plant Leaves AB -

The search for general patterns in the production and allocation of plant defense traits will be facilitated by characterizing multivariate suites of defense, as well as by studying additional plant taxa, particularly those with available genomic resources. Here, we investigated patterns of genetic variation in phytochemical defenses (phenylpropanoid glycosides, PPGs) in Mimulus guttatus (yellow monkeyflower). We grew plants derived from several natural populations, consisting of multiple full-sibling families within each population, in a common greenhouse environment. We found substantial variation in the constitutive multivariate PPG phenotype and in constitutive levels of individual phytochemicals within plants (among leaves of different ages), within populations (among full-sibling families), and among populations. Populations consisting of annual plants generally, but not always, had lower concentrations of phytochemicals than did populations of perennial plants. Populations differed in their plastic response to artificial herbivory, both in the overall multivariate PPG phenotype and in the individual phytochemicals. The relationship between phytochemistry and another defense trait, trichomes, differed among populations. Finally, we demonstrated that one of the PPGs, verbascoside, acts as a feeding stimulant rather than a feeding deterrent for a specialist herbivore of M. guttatus, the buckeye caterpillar (Junonia coenia Nymphalidae). Given its available genetic resources, numerous, easily accessible natural populations, and patterns of genetic variation highlighted in this research, M. guttatus provides an ideal model system in which to test ecological and evolutionary theories of plant-herbivore interactions.

VL - 39 SN - 0098-0331 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=23468225&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 4 ER - TY - JOUR T1 - Relative importance of genetic, ontogenetic, induction, and seasonal variation in producing a multivariate defense phenotype in a foundation tree species. JF - Oecologia Y1 - 2012 A1 - Holeski,Liza M A1 - Hillstrom,Michael L A1 - Whitham,Thomas G A1 - Lindroth,Richard L KW - Animals KW - Biological Evolution KW - Chimera KW - Coleoptera KW - Genetic Variation KW - Herbivory KW - Larva KW - Multivariate Analysis KW - Phenotype KW - Plant Leaves KW - Populus KW - Seasons KW - Trees AB -

Plant adaptations for defense against herbivory vary both among species and among genotypes. Moreover, numerous forms of within-plant variation in defense, including ontogeny, induction, and seasonal gradients, allow plants to avoid expending resources on defense when herbivores are absent. We used an 18-year-old cottonwood common garden composed of Populus fremontii, Populus angustifolia, and their naturally occurring F(1) hybrids (collectively referred to as "cross types") to quantify and compare the relative influences of three hierarchical levels of variation (between cross types, among genotypes, and within individual genotypes) on univariate and multivariate phytochemical defense traits. Within genotypes, we evaluated ontogeny, induction (following cottonwood leaf beetle herbivory), and seasonal variation. We compared the effect sizes of each of these sources of variation on the plant defense phenotype. Three major patterns emerged. First, we observed significant differences in concentrations of defense phytochemicals among cross types, and/or among genotypes within cross types. Second, we found significant genetic variation for within-plant differences in phytochemical defenses: (a) based on ontogeny, levels of constitutive phenolic glycosides were nearly three times greater in the mature zone than in the juvenile zone within one cottonwood cross type, but did not significantly differ within another cross type; (b) induced levels of condensed tannins increased up to 65 % following herbivore damage within one cottonwood cross type, but were not significantly altered in another cross type; and (c) concentrations of condensed tannins tended to increase across the season, but did not do so across all cross types. Third, our estimates of effect size demonstrate that the magnitude of within-plant variation in a phytochemical defense can rival the magnitude of differences in defense among genotypes and/or cross types. We conclude that, in cottonwood and likely other plant species, multiple forms of within-individual variation have the potential to substantially influence ecological and evolutionary processes.

VL - 170 SN - 0029-8549 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=22652923&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 3 ER - TY - JOUR T1 - Genetically-based trait variation within a foundation tree species influences a dominant bark lichen . JF - Fungal Ecology Y1 - 2011 A1 - Lamit,LJ A1 - MA Bowker A1 - LM Holeski A1 - Næsborg,RR A1 - Wooley,SC A1 - M Zinkgraf A1 - Lindroth,RL A1 - TG Whitham A1 - CA Gehring VL - 4 N1 - [Original String]:Lamit LJ, Bowker MA, Holeski LM, Næsborg RR, Wooley SC, Zinkgraf M, Lindroth RL, Whitham TG, Gehring CA. 2011. Genetically-based trait variation within a foundation tree species influences a dominant bark lichen . Fungal Ecology 4:103-109. ER - TY - JOUR T1 - Separating ontogenetic and environmental determination of resistance to herbivory in cottonwood. JF - Ecology Y1 - 2009 A1 - Holeski,Liza M A1 - Kearsley,Michael J C A1 - Whitham,Thomas G KW - Animals KW - Aphids KW - Biological Evolution KW - Ecosystem KW - Feeding Behavior KW - Populus AB -

We used narrowleaf cottonwood, Populus angustifolia, and the gall-forming aphid, Pemphigus betae, to determine the extent to which ontogenetic variation in resistance to herbivory is due to endogenous, stable genetic influences. In a three-year common garden trial using ramets propagated from the top, middle, and bottom of mature trees, we found that the resistance of trees to aphids was significantly higher in top vs. bottom source ramets, supporting the hypothesis of a stable, genetically programmed component to aphid resistance. The magnitude of ontogenetically based variation in resistance within an individual tree is comparable to the genetic variation in resistance among narrowleaf cottonwood genotypes or populations found in other studies. These ontogenetic-based findings have the potential to alter ecological interactions and evolutionary trajectories of plant-herbivore interactions.

VL - 90 SN - 0012-9658 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=19967853&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 11 ER -