TY - JOUR T1 - Common garden experiments disentangle plant genetic and environmental contributions to ectomycorrhizal fungal community structure. JF - New Phytologist Y1 - 2018 A1 - Patterson, A.M. A1 - Flores-Rentería, L. A1 - A.V. Whipple A1 - Whitham, T.G. A1 - Gehring, C.A. AB -

The interactions among climate change, plant genetic variation and fungal mutualists are poorly understood, but probably important to plant survival under drought. We examined these interactions by studying the ectomycorrhizal fungal (EMF) communities of pinyon pine seedlings (Pinus edulis) planted in a wildland ecosystem experiencing two decades of climate change‐related drought We established a common garden containing P. edulis seedlings of known maternal lineages (drought tolerant, DT; drought intolerant, DI), manipulated soil moisture and measured EMF community structure and seedling growth. Three findings emerged: EMF community composition differed at the phylum level between DT and DI seedlings, and diversity was two‐fold greater in DT than in DI seedlings. EMF communities of DT seedlings did not shift with water treatment and were dominated by an ascomycete, Geopora sp. By contrast, DI seedlings shifted to basidiomycete dominance with increased moisture, demonstrating a lineage by environment interaction. DT seedlings grew larger than DI seedlings in high (28%) and low (50%) watering treatments. These results show that inherited plant traits strongly influence microbial communities, interacting with drought to affect seedling performance. These interactions and their potential feedback effects may influence the success of trees, such as P. edulis, in future climates.

VL - 221 UR - https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.15352 IS - 1 ER - TY - JOUR T1 - Arthropod communities on hybrid and parental cottonwoods are phylogenetically structured by tree type: Implications for conservation of biodiversity in plant hybrid zones. JF - Ecology and evolution Y1 - 2017 A1 - Jarvis,Karl J A1 - Allan,Gerard J A1 - Craig,Ashley J A1 - Beresic-Perrins,Rebecca K A1 - Wimp,Gina A1 - Gehring,Catherine A A1 - Whitham,Thomas G AB -

Although hybridization in plants has been recognized as an important pathway in plant speciation, it may also affect the ecology and evolution of associated communities. Cottonwood species (Populus angustifolia and P. fremontii) and their naturally occurring hybrids are known to support different plant, animal, and microbial communities, but no studies have examined community structure within the context of phylogenetic history. Using a community composed of 199 arthropod species, we tested for differences in arthropod phylogenetic patterns within and among hybrid and parental tree types in a common garden. Three major patterns emerged. (1) Phylogenetic diversity (PD) was significantly different between arthropod communities on hybrids and Fremont cottonwood when pooled by tree type. (2) Mean phylogenetic distance (MPD) and net relatedness index (NRI) indicated that communities on hybrid trees were significantly more phylogenetically overdispersed than communities on either parental tree type. (3) Community distance (Dpw) indicated that communities on hybrids were significantly different than parental species. Our results show that arthropod communities on parental and hybrid cottonwoods exhibit significantly different patterns of phylogenetic structure. This suggests that arthropod community assembly is driven, in part, by plant-arthropod interactions at the level of cottonwood tree type. We discuss potential hypotheses to explain the effect of plant genetic dissimilarity on arthropod phylogenetic community structure, including the role of competition and environmental filtering. Our findings suggest that cottonwood species and their hybrids function as evolutionarily significant units (ESUs) that affect the assembly and composition of associated arthropod communities and deserve high priority for conservation.

VL - 7 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=28808554&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 15 ER - TY - JOUR T1 - Arthropod communities on hybrid and parental cottonwoods are phylogenetically structured by tree type: Implications for conservation of biodiversity in plant hybrid zones. JF - Ecology and Evolution Y1 - 2017 A1 - Jarvis, K.J. A1 - Allan, G.J. A1 - Craig, A. J. A1 - Beresic-Perrins, R. K.. A1 - G. Wimp A1 - Gehring, C.A. A1 - T. G. Whitham KW - arthropod phylogenetics KW - common garden KW - community genetics KW - community phylogenetics KW - foundation species KW - hybridization AB -

Although hybridization in plants has been recognized as an important pathway in plant speciation, it may also affect the ecology and evolution of associated communities. Cottonwood species (Populus angustifolia and P. fremontii) and their naturally occurring hybrids are known to support different plant, animal, and microbial communities, but no studies have examined community structure within the context of phylogenetic history. Using a community composed of 199 arthropod species, we tested for differences in arthropod phylogenetic patterns within and among hybrid and parental tree types in a common garden. Three major patterns emerged. (1) Phylogenetic diversity (PD) was significantly different between arthropod communities on hybrids and Fremont cottonwood when pooled by tree type. (2) Mean phylogenetic distance (MPD) and net relatedness index (NRI) indicated that communities on hybrid trees were significantly more phylogenetically overdispersed than communities on either parental tree type. (3) Community distance (D pw) indicated that communities on hybrids were significantly different than parental species. Our results show that arthropod communities on parental and hybrid cottonwoods exhibit significantly different patterns of phylogenetic structure. This suggests that arthropod community assembly is driven, in part, by plant–arthropod interactions at the level of cottonwood tree type. We discuss potential hypotheses to explain the effect of plant genetic dissimilarity on arthropod phylogenetic community structure, including the role of competition and environmental filtering. Our findings suggest that cottonwood species and their hybrids function as evolutionarily significant units (ESUs) that affect the assembly and composition of associated arthropod communities and deserve high priority for conservation.

VL - 7 UR - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5551273/ IS - 15 ER - TY - JOUR T1 - Genetics-based interactions of foundation species affect community diversity, stability and network structure. JF - Proceedings of the Royal Society B Biological ... Y1 - 2017 A1 - AR Keith A1 - JK Bailey A1 - Lau,MK A1 - TG Whitham AB - react-text: 446 A central issue in the field of community genetics is the expectation that trait variation among genotypes play a defining role in structuring associated species and in forming community phenotypes. Quantifying the existence of such community phenotypes in two common garden environments also has important consequences for our understanding of gene-by-environment interactions at the community... /react-text react-text: 447 /react-text [Show full abstract] VL - 284 UR - http://europepmc.org/abstract/MED/28490623 IS - 1854 ER - TY - CHAP T1 - IN PRESS: Using the Southwest Experimental Garden Array to enhance riparian restoration in response to global change: Identifying and deploying genotypes and populations for current and future environments. T2 - In Riparian research and management: Past, present, future. Y1 - 2017 A1 - Whitham, T.G. A1 - C.A. Gehring A1 - H.M. Bothwell A1 - H.F. Cooper A1 - J.B. Hull A1 - G.J. Allan A1 - K.C. Grady A1 - L. Markovchick A1 - S.M. Shuster A1 - J. Parker A1 - A.E. Cadmus A1 - D.H. Ikeda A1 - R.K. Bangert JF - In Riparian research and management: Past, present, future. PB - Gen. Tech. Rep. RMRS-GTR-inpress Fort Collins U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. CY - Fort Collins, CO, USA VL - 2 ER - TY - JOUR T1 - Local biotic adaptation of trees and shrubs to plant neighbors. JF - Okios Y1 - 2017 A1 - Grady, K.C. A1 - Wood, T. E. A1 - Kolb, T. E. A1 - Hersch-Green, E. A1 - Shuster, S.M. A1 - Gehring, C. A. A1 - Hart, S.C. A1 - Allan, G.J. A1 - T. G. Whitham AB -

Natural selection as a result of plant–plant interactions can lead to local biotic adaptation. This may occur where species frequently interact and compete intensely for resources limiting growth, survival, and reproduction. Selection is demonstrated by comparing a genotype interacting with con‐ or hetero‐specific sympatric neighbor genotypes with a shared site‐level history (derived from the same source location), to the same genotype interacting with foreign neighbor genotypes (from different sources). Better genotype performance in sympatric than allopatric neighborhoods provides evidence of local biotic adaptation. This pattern might be explained by selection to avoid competition by shifting resource niches (differentiation) or by interactions benefitting one or more members (facilitation). We tested for local biotic adaptation among two riparian trees, Populus fremontii and Salix gooddingii, and the shrub Salix exigua by transplanting replicated genotypes from multiple source locations to a 17 000 tree common garden with sympatric and allopatric treatments along the Colorado River in California. Three major patterns were observed: 1) across species, 62 of 88 genotypes grew faster with sympatric neighbors than allopatric neighbors; 2) these growth rates, on an individual tree basis, were 44, 15 and 33% higher in sympatric than allopatric treatments for P. fremontii, S. exigua and S. gooddingii, respectively, and; 3) survivorship was higher in sympatric treatments for P. fremontii and S. exigua. These results support the view that fitness of foundation species supporting diverse communities and dominating ecosystem processes is determined by adaptive interactions among multiple plant species with the outcome that performance depends on the genetic identity of plant neighbors. The occurrence of evolution in a plant‐community context for trees and shrubs builds on ecological evolutionary research that has demonstrated co‐evolution among herbaceous taxa, and evolution of native species during exotic plants invasion, and taken together, refutes the concept that plant communities are always random associations.

VL - 126 UR - https://onlinelibrary.wiley.com/doi/full/10.1111/oik.03240 IS - 4 ER - TY - CONF T1 - The reality of climate change and the need for genetics approaches in riparian, river and watershed restoration to maintain biodiversity in changing environments. Y1 - 2017 A1 - TG Whitham ED - Ralston,BE ED - Sarr,DA T3 - Case studies of riparian and watershed restoration in the southwestern United States—Principles, challenges, and successes PB - U.S. Geological Survey Open-File Report 2017-1091 SN - 1090-7165 UR - https://pubs.er.usgs.gov/publication/ofr20171091 ER - TY - JOUR T1 - Tree genetics defines fungal partner communities that may confer drought tolerance. JF - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES Y1 - 2017 A1 - Gehring, C.A. A1 - Sthultz, C.M. A1 - Flores-Rentería, L. A1 - A.V. Whipple A1 - T.G. Whitham AB -

Plant genetic variation and soil microorganisms are individually known to influence plant responses to climate change, but the interactive effects of these two factors are largely unknown. Using long-term observational studies in the field and common garden and greenhouse experiments of a foundation tree species (Pinus edulis) and its mutualistic ectomycorrhizal fungal (EMF) associates, we show that EMF community composition is under strong plant genetic control. Seedlings acquire the EMF community of their seed source trees (drought tolerant vs. drought intolerant), even when exposed to inoculum from the alternate tree type. Drought-tolerant trees had 25% higher growth and a third the mortality of drought-intolerant trees over the course of 10 y of drought in the wild, traits that were also observed in their seedlings in a common garden. Inoculation experiments show that EMF communities are critical to drought tolerance. Drought-tolerant and drought-intolerant seedlings grew similarly when provided sterile EMF inoculum, but drought-tolerant seedlings grew 25% larger than drought-intolerant seedlings under dry conditions when each seedling type developed its distinct EMF community. This demonstration that particular combinations of plant genotype and mutualistic EMF communities improve the survival and growth of trees with drought is especially important, given the vulnerability of forests around the world to the warming and drying conditions predicted for the future.

VL - 114 UR - https://www.pnas.org/content/114/42/11169 IS - 42 ER - TY - JOUR T1 - Bud phenology and growth are subject to divergent selection across a latitudinal gradient in Populus angustifolia and impact adaptation across the distributional range and associated arthropods. JF - Ecology and evolution Y1 - 2016 A1 - Evans,Luke M A1 - Kaluthota,Sobadini A1 - Pearce,David W A1 - Allan,Gerard J A1 - Floate,Kevin A1 - Rood,Stewart B A1 - Whitham,Thomas G AB -

Temperate forest tree species that span large geographical areas and climatic gradients often have high levels of genetic variation. Such species are ideal for testing how neutral demographic factors and climate-driven selection structure genetic variation within species, and how this genetic variation can affect ecological communities. Here, we quantified genetic variation in vegetative phenology and growth traits in narrowleaf cottonwood, Populus angustifolia, using three common gardens planted with genotypes originating from source populations spanning the species' range along the Rocky Mountains of North America (ca. 1700 km). We present three main findings. First, we found strong evidence of divergent selection (Q ST > F ST) on fall phenology (bud set) with adaptive consequences for frost avoidance. We also found evidence for selection on bud flush duration, tree height, and basal diameter, resulting in population differentiation. Second, we found strong associations with climate variables that were strongly correlated with latitude of origin. More strongly differentiated traits also showed stronger climate correlations, which emphasizes the role that climate has played in divergent selection throughout the range. We found population × garden interaction effects; for some traits, this accounted for more of the variance than either factor alone. Tree height was influenced by the difference in climate of the source and garden locations and declined with increasing transfer distance. Third, growth traits were correlated with dependent arthropod community diversity metrics. Synthesis. Overall, we conclude that climate has influenced genetic variation and structure in phenology and growth traits and leads to local adaptation in P. angustifolia, which can then impact dependent arthropod species. Importantly, relocation of genotypes far northward or southward often resulted in poor growth, likely due to a phenological mismatch with photoperiod, the proximate cue for fall growth cessation. Genotypes moved too far southward suffer from early growth cessation, whereas those moved too far northward are prone to fall frost and winter dieback. In the face of current and forecasted climate change, habitat restoration, forestry, and tree breeding efforts should utilize these findings to better match latitudinal and climatic source environments with management locations for optimal future outcomes.

VL - 6 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=27386097&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 13 ER - TY - JOUR T1 - Climate change perils for dioecious plant species. JF - Nature Plant 16109 Y1 - 2016 A1 - KR Hultine A1 - Grady,KC A1 - Wood,TE A1 - SM Shuster A1 - Stella,JC A1 - TG Whitham VL - 109 IS - 2 N1 - [Original String]:Hultine, K. R., Grady, K. C., Wood, T. E., Shuster, S. M., Stella, J. C. and Whitham, T.G. (2016). Climate change perils for dioecious plant species. Nature Plant, 109 (2): 16109. ER - TY - JOUR T1 - Genetic variation in NIN1 and C/VIF1 genes is significantly associated with Populus angustifolia resistance to a galling herbivore, Pemphigus betae. JF - Journal of insect physiology Y1 - 2016 A1 - Zinkgraf,Matthew S A1 - Meneses,Nashelly A1 - Whitham,Thomas G A1 - Allan,Gerard J KW - Animals KW - Aphids KW - beta-Fructofuranosidase KW - Enzyme Inhibitors KW - Genes, Plant KW - Genetic Variation KW - Haplotypes KW - Herbivory KW - Plant Immunity KW - Plant Proteins KW - Plant Tumors KW - Polymorphism, Single Nucleotide KW - Populus AB -

The identification of genes associated with ecologically important traits provides information on the potential genetic mechanisms underlying the responses of an organism to its natural environment. In this study, we investigated the genetic basis of host plant resistance to the gall-inducing aphid, Pemphigus betae, in a natural population of 154 narrowleaf cottonwoods (Populus angustifolia). We surveyed genetic variation in two genes putatively involved in sink-source relations and a phenology gene that co-located in a previously identified quantitative trait locus for resistance to galling. Using a candidate gene approach, three major findings emerged. First, natural variation in tree resistance to galling was repeatable. Sampling of the same tree genotypes 20 years after the initial survey in 1986 show that 80% of the variation in resistance was due to genetic differences among individuals. Second, we identified significant associations at the single nucleotide polymorphism and haplotype levels between the plant neutral invertase gene NIN1 and tree resistance. Invertases are a class of sucrose hydrolyzing enzymes and play an important role in plant responses to biotic stress, including the establishment of nutrient sinks. These associations with NIN1 were driven by a single nucleotide polymorphism (NIN1_664) located in the second intron of the gene and in an orthologous sequence to two known regulatory elements. Third, haplotypes from an inhibitor of invertase (C/VIF1) were significantly associated with tree resistance. The identification of genetic variation in these two genes provides a starting point to understand the possible genetic mechanisms that contribute to tree resistance to gall formation. We also build on previous work demonstrating that genetic differences in sink-source relationships of the host influence the ability of P. betae to manipulate the flow of nutrients and induce a nutrient sink.

VL - 84 SN - 0022-1910 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=26518288&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. ER - TY - JOUR T1 - Genetically informed ecological niche models improve climate change predictions JF - Global Change Biology Y1 - 2016 A1 - DH Ikeda A1 - Max,TL A1 - GJ Allan A1 - Lau,MK A1 - SM Shuster A1 - TG Whitham ER - TY - JOUR T1 - Genotypic variation in foundation species generates network structure that may drive community dynamics and evolution. JF - Ecology Y1 - 2016 A1 - Lau,Matthew K A1 - Keith,Arthur R A1 - Borrett,Stuart R A1 - Shuster,Stephen M A1 - Whitham,Thomas G KW - Animals KW - Biological Evolution KW - Computer Simulation KW - Food Chain KW - Genetic Variation KW - Genotype KW - Insecta KW - Models, Biological KW - Populus AB -

Although genetics in a single species is known to impact whole communities, little is known about how genetic variation influences species interaction networks in complex ecosystems. Here, we examine the interactions in a community of arthropod species on replicated genotypes (clones) of a foundation tree species, Populus angustifolia James (narrowleaf cottonwood), in a long-term, common garden experiment using a bipartite "genotype-species" network perspective. We combine this empirical work with a simulation experiment designed to further investigate how variation among individual tree genotypes can impact network structure. Three findings emerged: (1) the empirical "genotype-species network" exhibited significant network structure with modularity being greater than the highly conservative null model; (2) as would be expected given a modular network structure, the empirical network displayed significant positive arthropod co-occurrence patterns; and (3) furthermore, the simulations of "genotype-species" networks displayed variation in network structure, with modularity in particular clearly increasing, as genotypic variation increased. These results support the conclusion that genetic variation in a single species contributes to the structure of ecological interaction networks, which could influence eco-ogical dynamics (e.g., assembly and stability) and evolution in a community context.

VL - 97 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=27197399&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 3 ER - TY - JOUR T1 - G.M. Allan, and Tree genetics strongly effect forest productivity, but intraspecific diversity-productivity relationships do not. JF - FUNCTIONAL ECOLOGY DOI 1011111365243512733 Y1 - 2016 A1 - Fischer,DG A1 - Wimp,E A1 - Hersch-Green,RK A1 - Bangert,CJ A1 - LeRoy,JK A1 - Bailey,JA A1 - Schweitzer,C A1 - Dirks,SC A1 - Hart,GJ A1 - TG Whitham VL - 31 N1 - [Original String]:Fischer, D.G., G.M. Wimp, E. Hersch-Green, R.K. Bangert, C.J. LeRoy, J.K. Bailey, J.A. Schweitzer, C. Dirks, S.C. Hart, G.J. Allan, and Whitham, T.G. 2016. Tree genetics strongly effect forest productivity, but intraspecific diversity-productivity relationships do not. FUNCTIONAL ECOLOGY 31:520-529. DOI: 10.1111/1365-2435.12733 ER - TY - JOUR T1 - Plant-herbivore interactions in a trispecific hybrid swarm of Populus: assessing support for hypotheses of hybrid bridges, evolutionary novelty and genetic similarity. JF - The New phytologist Y1 - 2016 A1 - Floate,Kevin D A1 - Godbout,Julie A1 - Lau,Matthew K A1 - Isabel,Nathalie A1 - Whitham,Thomas G KW - Alberta KW - Animals KW - Arthropods KW - biodiversity KW - Biological Evolution KW - Chimera KW - Ecosystem KW - Herbivory KW - Hybridization, Genetic KW - Populus KW - Trees KW - Utah AB -

Natural systems of hybridizing plants are powerful tools with which to assess evolutionary processes between parental species and their associated arthropods. Here we report on these processes in a trispecific hybrid swarm of Populus trees. Using field observations, common garden experiments and genetic markers, we tested the hypothesis that genetic similarities among hosts underlie the distributions of 10 species of gall-forming arthropods and their ability to adapt to new host genotypes.the degree of genetic relatedness among parental species determines whether hybridization is primarily bidirectional or unidirectional; host genotype and genetic similarity strongly affect the distributions of gall-forming species, individually and as a community. These effects were detected observationally in the wild and experimentally in common gardens; correlations between the diversity of host genotypes and their associated arthropods identify hybrid zones as centres of biodiversity and potential species interactions with important ecological and evolutionary consequences. These findings support both hybrid bridge and evolutionary novelty hypotheses. However, the lack of parallel genetic studies on gall-forming arthropods limits our ability to define the host of origin with their subsequent shift to other host species or their evolution on hybrids as their final destination.

VL - 209 SN - 0028-646X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=26346922&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 2 ER - TY - JOUR T1 - A robust method to determine historical annual cone production among slow-growing conifers. JF - Canadian Journal of Forest Research Y1 - 2016 A1 - Redmond,M A1 - Weisberg,P A1 - Cobb,NS A1 - CA Gehring A1 - AV Whipple A1 - TG Whitham VL - 398 N1 - [Original String]:Redmond, M., Weisberg, P., Cobb, N. S., Gehring, C. A., Whipple, A. V., & Whitham, T. G. (2016). A robust method to determine historical annual cone production among slow-growing conifers. Canadian Journal of Forest Research, 398, 1-6. 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 - A genetics-based universal community transfer function for predicting the impacts of climate change on future communities. JF - Functional Ecology Y1 - 2014 A1 - DH Ikeda A1 - Bothwell,HM A1 - Lau,MK A1 - O’Neill,GA A1 - Grady,KC A1 - TG Whitham KW - Acetamides KW - Amines KW - Cyclohexanecarboxylic Acids KW - Dried Blood Spot Testing KW - Fluoroacetates KW - gamma-Aminobutyric Acid KW - Gas Chromatography-Mass Spectrometry KW - Humans KW - Linear Models KW - Reproducibility of Results KW - Sensitivity and Specificity KW - Spectrometry, Mass, Electrospray Ionization KW - Tandem Mass Spectrometry KW - Trimethylsilyl Compounds KW - Valproic Acid VL - 28 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=24889681&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. ER - TY - JOUR T1 - Conservative leaf economic traits correlate with fast growth of genotypes of a foundation riparian species near the thermal maximum extent of its geographic range . JF - Functional Ecology Y1 - 2013 A1 - Grady,KC A1 - Laughlin,DC A1 - Ferrier,SM A1 - TE Kolb A1 - Hart,SC A1 - GJ Allan A1 - TG Whitham VL - 27 N1 - [Original String]:Grady KC, Laughlin DC, Ferrier SM, Kolb TE, Hart SC, Allan GJ, Whitham TG. 2013. Conservative leaf economic traits correlate with fast growth of genotypes of a foundation riparian species near the thermal maximum extent of its geographic range . Functional Ecology 27:427-438. ER - TY - JOUR T1 - Genetic basis of pathogen community structure for foundation tree species in a common garden and in the wild . JF - Journal of Ecology Y1 - 2013 A1 - Busby,PE A1 - Newcombe,G A1 - Dirzo,R A1 - TG Whitham VL - 101 N1 - [Original String]:Busby PE, Newcombe G, Dirzo R, Whitham TG. 2013. Genetic basis of pathogen community structure for foundation tree species in a common garden and in the wild . Journal of Ecology 101:867-877. ER - TY - JOUR T1 - Leaf litter quality affects aquatic insect emergence: contrasting patterns from two foundation trees. JF - Oecologia Y1 - 2013 A1 - Compson,Zacchaeus G A1 - Adams,Kenneth J A1 - Edwards,Joeseph A A1 - Maestas,Jesse M A1 - Whitham,Thomas G A1 - Jane C Marks KW - Animals KW - arizona KW - Biota KW - Food Chain KW - Insecta KW - Plant Leaves KW - Populus KW - Rivers KW - Species Specificity AB -

Reciprocal subsidies between rivers and terrestrial habitats are common where terrestrial leaf litter provides energy to aquatic invertebrates while emerging aquatic insects provide energy to terrestrial predators (e.g., birds, lizards, spiders). We examined how aquatic insect emergence changed seasonally with litter from two foundation riparian trees, whose litter often dominates riparian streams of the southwestern United States: Fremont (Populus fremontii) and narrowleaf (Populus angustifolia) cottonwood. P. fremontii litter is fast-decomposing and lower in defensive phytochemicals (i.e., condensed tannins, lignin) relative to P. angustifolia. We experimentally manipulated leaf litter from these two species by placing them in leaf enclosures with emergence traps attached in order to determine how leaf type influenced insect emergence. Contrary to our initial predictions, we found that packs with slow-decomposing leaves tended to support more emergent insects relative to packs with fast-decomposing leaves. Three findings emerged. Firstly, abundance (number of emerging insects m(-2) day(-1)) was 25% higher on narrowleaf compared to Fremont leaves for the spring but did not differ in the fall, demonstrating that leaf quality from two dominant trees of the same genus yielded different emergence patterns and that these patterns changed seasonally. Secondly, functional feeding groups of emerging insects differed between treatments and seasons. Specifically, in the spring collector-gatherer abundance and biomass were higher on narrowleaf leaves, whereas collector-filterer abundance and biomass were higher on Fremont leaves. Shredder abundance and biomass were higher on narrowleaf leaves in the fall. Thirdly, diversity (Shannon's H') was higher on Fremont leaves in the spring, but no differences were found in the fall, showing that fast-decomposing leaves can support a more diverse, complex emergent insect assemblage during certain times of the year. Collectively, these results challenge the notion that leaf quality is a simple function of decomposition, suggesting instead that aquatic insects benefit differentially from different leaf types, such that some use slow-decomposing litter for habitat and its temporal longevity and others utilize fast-decomposing litter with more immediate nutrient release.

VL - 173 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=23532583&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 2 ER - TY - JOUR T1 - Plant genetics and interspecific competitive interactions determine ectomycorrhizal fungal community responses to climate change . JF - Molecular Ecology Y1 - 2013 A1 - CA Gehring A1 - Flores-Rentería,D A1 - CM Sthultz A1 - Leonard,TM A1 - L Flores-Renteria A1 - AV Whipple A1 - TG Whitham VL - 23 N1 - [Original String]:Gehring CA, Flores-Rentería D, Sthultz CM, Leonard TM, Flores-Rentería L, Whipple AV, Whitham TG. 2013. Plant genetics and interspecific competitive interactions determine ectomycorrhizal fungal community responses to climate change . Molecular Ecology 23:1379-1391. ER - TY - JOUR T1 - Community specificity: life and afterlife effects of genes. JF - Trends in plant science Y1 - 2012 A1 - Whitham,Thomas G A1 - Gehring,Catherine A A1 - Lamit,Louis J A1 - Wojtowicz,Todd A1 - Evans,Luke M A1 - Keith,Arthur R A1 - Smith,David Solance KW - Animals KW - Arthropods KW - Biological Evolution KW - Ecosystem KW - Genotype KW - Herbivory KW - Host-Parasite Interactions KW - Models, Biological KW - Plants KW - Species Specificity AB -

Community-level genetic specificity results when individual genotypes or populations of the same species support different communities. Our review of the literature shows that genetic specificity exhibits both life and afterlife effects; it is a widespread phenomenon occurring in diverse taxonomic groups, aquatic to terrestrial ecosystems, and species-poor to species-rich systems. Such specificity affects species interactions, evolution, ecosystem processes and leads to community feedbacks on the performance of the individuals expressing the traits. Thus, genetic specificity by communities appears to be fundamentally important, suggesting that specificity is a major driver of the biodiversity and stability of the world's ecosystems.

VL - 17 SN - 1360-1385 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=22322002&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 5 ER - TY - BOOK T1 - From genes to ecosystems: emerging concepts bridging ecological and evolutionary dynamics. Y1 - 2012 A1 - JK Bailey A1 - Schweitzer,JA A1 - Fitzpatrick,BM A1 - Genung,MA A1 - Pregitzer,CC A1 - M Zinkgraf A1 - TG Whitham A1 - Keith,A A1 - Reilly-Wapstra,JM A1 - Potts,BM A1 - Rehill,BJ A1 - LeRoy,CJ A1 - Fischer,DG A1 - Iason,GR A1 - Dicke,M A1 - Hartley,SE ED - Iason,GR ED - Dicke,M ED - Hartley,SE PB - Cambridge University Press CY - New York N1 - [Original String]:Bailey JK, Schweitzer JA, Úbeda F, Fitzpatrick BM, Genung MA, Pregitzer CC, Zinkgraf M, Whitham TG, Keith A, O’Reilly-Wapstra JM, Potts BM, Rehill BJ, LeRoy CJ, Fischer DG. 2012. From genes to ecosystems: emerging concepts bridging ecological and evolutionary dynamics. In Iason GR, Dicke M, Hartley SE, editors The ecology of plant secondary metabolites: from genes to global processes New York (NY): Cambridge University Press; p 269-286. ER - TY - JOUR T1 - Genetic components to belowground carbon fluxes in a riparian forest ecosystem: a common garden approach. JF - The New phytologist Y1 - 2012 A1 - Lojewski,Nathan R A1 - Fischer,Dylan G A1 - JK Bailey A1 - Jennifer A Schweitzer A1 - Whitham,Thomas G A1 - Stephen C Hart KW - Carbon KW - Carbon Cycle KW - Carbon Dioxide KW - Chimera KW - Crosses, Genetic KW - Ecosystem KW - Genetic Variation KW - Genotype KW - Populus KW - Soil KW - Trees AB -

Soil carbon dioxide (CO(2)) efflux is a major component of terrestrial carbon (C) cycles; yet, the demonstration of covariation between overstory tree genetic-based traits and soil C flux remains a major frontier in understanding biological controls over soil C. Here, we used a common garden with two native tree species, Populus fremontii and P. angustifolia, and their naturally occurring hybrids to test the predictability of belowground C fluxes on the basis of taxonomic identity and genetic marker composition of replicated clones of individual genotypes. Three patterns emerged: soil CO(2) efflux and ratios of belowground flux to aboveground productivity differ by as much as 50-150% as a result of differences in clone identity and cross type; on the basis of Mantel tests of molecular marker matrices, we found that c. 30% of this variation was genetically based, in which genetically similar trees support more similar soil CO(2) efflux under their canopies than do genetically dissimilar trees; and the patterns detected in an experimental garden match observations in the wild, and seem to be unrelated to measured abiotic factors. Our findings suggest that the genetic makeup of the plants growing on soil has a significant influence on the release of C from soils to the atmosphere.

VL - 195 SN - 0028-646X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=22642377&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 3 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 - The relative influences of host plant genotype and yearly abiotic variability in determining herbivore abundance. JF - Oecologia Y1 - 2012 A1 - Evans,Luke M A1 - James S Clark A1 - Whipple,Amy V A1 - Whitham,Thomas G KW - Animals KW - Bayes Theorem KW - Genotype KW - Herbivory KW - Mites KW - Population Density KW - Population Dynamics KW - Populus AB -

Both plant genotype and yearly abiotic variation affect herbivore population sizes, but long-term data have rarely been used to contrast the relative contributions of each. Using a hierarchical Bayesian model, we directly compare effects of these two factors on the population size of a common herbivore, Aceria parapopuli, on Populus angustifolia × fremontii F(1) hybrid trees growing in a common garden across 8 years. Several patterns emerged. First, the Bayesian posterior estimates of tree genotype effects on mite gall number ranged from 0.0043 to 229 on a linear scale. Second, year effect sizes across 8 years of study ranged from 0.133 to 1.895. Third, in comparing the magnitudes of genotypic versus yearly variation, we found that genotypic variation was over 130 times greater than variation among years. Fourth, precipitation in the previous year negatively affected gall abundances, but was minimal compared to tree genotype effects. These findings demonstrate the relative importance of tree genotypic variation in determining herbivore population size. However, given the demonstrated sensitivity of cottonwoods to drought, the loss of individual tree genotypes from an altered climate would have catastrophic impacts on mites that are dependent upon these genotypes for their survival.

VL - 168 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=21918874&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 2 ER - TY - JOUR T1 - Soil-mediated local adaptation alters seedling survival and performance . JF - Plant and Soil Y1 - 2012 A1 - Smith,DS A1 - Schweitzer,JA A1 - Turk,P A1 - JK Bailey A1 - Hart,SC A1 - SM Shuster A1 - TG Whitham VL - 352 N1 - [Original String]:Smith DS, Schweitzer JA, Turk P, Bailey JK, Hart SC, Shuster SM, Whitham TG. 2012. Soil-mediated local adaptation alters seedling survival and performance . Plant and Soil 352: 243-251. ER - TY - JOUR T1 - Genes to ecosystems: exploring the frontiers of ecology with one of the smallest biological units. JF - The New phytologist Y1 - 2011 A1 - Wymore,Adam S A1 - Keeley,Annika T H A1 - Yturralde,Kasey M A1 - Schroer,Melanie L A1 - Propper,Catherine R A1 - Whitham,Thomas G KW - Animals KW - Cell Respiration KW - climate change KW - Ecosystem KW - Environmental Pollution KW - Female KW - Fishes KW - Gene Expression KW - Haplotypes KW - Humans KW - Introduced Species KW - Male KW - Plants KW - Population Dynamics KW - Sciuridae AB -

Genes and their expression levels in individual species can structure whole communities and affect ecosystem processes. Although much has been written about community and ecosystem phenotypes with a few model systems, such as poplar and goldenrod, here we explore the potential application of a community genetics approach with systems involving invasive species, climate change and pollution. We argue that community genetics can reveal patterns and processes that otherwise might remain undetected. To further facilitate the community genetics or genes-to-ecosystem concept, we propose four community genetics postulates that allow for the conclusion of a causal relationship between the gene and its effect on the ecosystem. Although most current studies do not satisfy these criteria completely, several come close and, in so doing, begin to provide a genetic-based understanding of communities and ecosystems, as well as a sound basis for conservation and management practices.

VL - 191 SN - 0028-646X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=21631507&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1 ER - TY - JOUR T1 - A genetic basis for the manipulation of sink-source relationships by the galling aphid Pemphigus batae. JF - Oecologia Y1 - 2011 A1 - Compson,Zacchaeus G A1 - Larson,Katherine C A1 - Zinkgraf,Matthew S A1 - Whitham,Thomas G KW - Animals KW - Aphids KW - Carbon Radioisotopes KW - Ecosystem KW - Feeding Behavior KW - Host-Parasite Interactions KW - Phloem KW - Plant Leaves KW - Plant Shoots KW - Populus AB -

We examined how the galling aphid Pemphigus batae manipulates resource translocation patterns of resistant and susceptible narrowleaf cottonwood Populus angustifolia. Using carbon-14 ((14)C)-labeling experiments in common garden trials, five patterns emerged. First, although aphid galls on resistant and susceptible genotypes did not differ in their capacity to intercept assimilates exported from the leaf they occupied, aphids sequestered 5.8-fold more assimilates from surrounding leaves on susceptible tree genotypes compared to resistant genotypes. Second, gall sinks on the same side of a shoot as a labeled leaf were 3.4-fold stronger than gall sinks on the opposite side of a shoot, which agrees with patterns of vascular connections among leaves of the same shoot (orthostichy). Third, plant genetic-based traits accounted for 26% of the variation in sink strength of gall sinks and 41% of the variation in sink strength of a plant's own bud sinks. Fourth, tree susceptibility to aphid gall formation accounted for 63% of the variation in (14)C import, suggesting strong genetic control of sink-source relationships. Fifth, competition between two galls was observed on a susceptible but not a resistant tree. On the susceptible tree distal aphids intercepted 1.5-fold more (14)C from the occupied leaf than did basal aphids, but basal aphids compensated for the presence of a distal competitor by almost doubling import to the gall from surrounding leaves. These findings and others, aimed at identifying candidate genes for resistance, argue the importance of including plant genetics in future studies of the manipulation of translocation patterns by phytophageous insects.

VL - 167 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=21667296&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 3 ER - TY - JOUR T1 - Genetic variation in productivity of foundation riparian species at the edge of their distribution: implications for restoration and assisted migration in a warming climate . JF - Global Change Biology Y1 - 2011 A1 - Grady,KC A1 - Ferrier,SM A1 - TE Kolb A1 - Hart,SC A1 - Allan,GA A1 - TG Whitham VL - 17 N1 - [Original String]:Grady KC, Ferrier SM, Kolb TE, Hart SC, Allan GA, Whitham TG. 2011. Genetic variation in productivity of foundation riparian species at the edge of their distribution: implications for restoration and assisted migration in a warming climate . Global Change Biology 17:3724-3735. 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 - A geographic mosaic of trophic interactions and selection: trees, aphids and birds JF - Journal of Evolutionary Biology Y1 - 2011 A1 - Smith,DS A1 - JK Bailey A1 - SM Shuster A1 - TG Whitham KW - Administration, Inhalation KW - Administration, Intranasal KW - Aerosols KW - Animals KW - Female KW - Influenza A Virus, H3N2 Subtype KW - Lung KW - Lung Diseases KW - Mice KW - Mice, Inbred BALB C KW - Orthomyxoviridae Infections VL - 24 SN - 1010-061X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=21449723&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 2 ER - TY - JOUR T1 - Leaf ontogeny interacts with Bt modification to affect innate resistance in GM aspens JF - Chemoecology Y1 - 2011 A1 - Axelsson,EP A1 - Hjältén,J A1 - TG Whitham A1 - Julkunen-Tiitto,R A1 - Pilate,G AB - Bioassays with a non-target slug ( Deroceras spp.) and chemical analyses were conducted using leaf tissue from already existing genetically modified insect-resistant aspen trees to examine whether genetic modifications to produce Bacillus thuringiensis (Bt) toxins could affect plant phytochemistry, which in turn might influence plant–herbivore interactions. Three major patterns emerged. First, two independent modifications for Bt resistance affected the phytochemical profiles of leaves such that both were different from the isogenic wild-type (Wt) control leaves, but also different from each other. Among the contributors to these differences are substances with a presumed involvement in resistance, such as salicortin and soluble condensed tannins. Second, bioassays with one Bt line suggest that the modification somehow affected innate resistance (“Innate” is used here in opposition to the “acquired” Bt resistance) in ways such that slugs preferred Bt over Wt leaves. Third, the preference test suggests that the innate resistance in Bt relative to Wt plants may not be uniformly expressed throughout the whole plant and that leaf ontogeny interacts with the modification to affect resistance. This was manifested through an ontogenetic determined increase in leaf consumption that was more than four times higher in Bt compared to Wt leaves. Our result are of principal importance, as these indicate that genetic modifications can affect innate resistance and thus non-target herbivores in ways that may have commercial and/or environmental consequences. The finding of a modification–ontogeny interaction effect on innate resistance may be especially important in assessments of GM plants with a long lifespan such as trees. VL - 21 UR - http://link.springer.com/article/10.1007/s00049-011-0080-8 IS - 3 ER - TY - JOUR T1 - Phenotypic variation in nurse traits and community feedbacks define an alpine community. JF - Ecology letters Y1 - 2011 A1 - Michalet,Richard A1 - Xiao,Sa A1 - Touzard,Blaise A1 - David S Smith A1 - Cavieres,Lohengrin A A1 - Callaway,Ragan M A1 - Whitham,Thomas G KW - arizona KW - Ecosystem KW - Genotype KW - Geum KW - Models, Biological KW - Phenotype KW - Plant Leaves KW - Plant Roots KW - Plant Stems KW - Population Dynamics KW - Selection, Genetic AB -

Much is known about facilitation, but virtually nothing about the underlying genetic and evolutionary consequences of this important interaction. We assessed the potential of phenotypic differences in facilitative effects of a foundation species to determine the composition of an Alpine community in Arizona. Two phenotypes of Geum rossii occur along a gradient of disturbance, with 'tight' competitive cushions in stable conditions and 'loose' facilitative cushions in disturbed conditions. A common-garden study suggested that field-based traits may have a genetic basis. Field experiments showed that the reproductive fitness of G. rossii cushions decreased with increasing facilitation. Finally, using a dual-lattice model we showed that including the cost and benefit of facilitation may contribute to the co-occurrence of genotypes with contrasting facilitative effects. Our results indicate that changes in community composition due to phenotypic differences in facilitative effects of a foundation species may in turn affect selective pressures on the foundation species.

VL - 14 SN - 1461-023X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=21366815&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 5 ER - TY - JOUR T1 - A conditional trophic cascade: birds benefit faster growing trees with strong links between predators and plants. JF - Ecology Y1 - 2010 A1 - Bridgeland,William T A1 - Beier,Paul A1 - Kolb,Thomas A1 - Whitham,Thomas G KW - Animals KW - Birds KW - Food Chain KW - Insecta KW - Predatory Behavior KW - Time Factors KW - Trees AB -

Terrestrial systems are thought to be organized predominantly from the bottom-up, but there is a growing literature documenting top-down trophic cascades under certain ecological conditions. We conducted an experiment to examine how arthropod community structure on a foundation riparian tree mediates the ability of insectivorous birds to influence tree growth. We built whole-tree bird exclosures around 35 mature cottonwood (Populus spp.) trees at two sites in northern Utah, USA, to measure the effect of bird predation on arthropod herbivore and predator species richness, abundance, and biomass, and on tree performance. We maintained bird exclosures over two growing seasons and conducted nondestructive arthropod surveys that recorded 63652 arthropods of 689 morphospecies representing 19 orders. Five major patterns emerged: (1) We found a significant trophic cascade (18% reduction in trunk growth when birds were excluded) only at one site in one year. (2) The significant trophic cascade was associated with higher precipitation, tree growth, and arthropod abundance, richness, and biomass than other site-year combinations. (3) The trophic cascade was weak or not evident when tree growth and insect populations were low apparently due to drought. (4) Concurrent with the stronger trophic cascade, bird predation significantly reduced total arthropod abundance, richness, and biomass. Arthropod biomass was 67% greater on trees without bird predation. This pattern was driven largely by two herbivore groups (folivores and non-aphid sap-feeders) suggesting that birds targeted these groups. (5) Three species of folivores (Orthoptera: Melanoplus spp.) were strong links between birds and trees and were only present in the site and the year in which the stronger trophic cascade occurred. Our results suggest that this trophic system is predominately bottom-up driven, but under certain conditions the influence of top predators can stimulate whole tree growth. When the most limiting factor for tree growth switched from water availability to herbivory, the avian predators gained the potential to reduce herbivory. This potential could be realized when strong links between the birds and plant, i.e., species that were both abundant herbivores and preferred prey, were present.

VL - 91 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=20380198&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1 ER - TY - JOUR T1 - A genetic basis to community repeatability and stability. JF - Ecology Y1 - 2010 A1 - Keith,Arthur R A1 - JK Bailey A1 - Whitham,Thomas G KW - Animals KW - Arthropods KW - Biological Evolution KW - Ecosystem KW - Genotype KW - Populus AB -

Recent studies have shown that genetically based traits of plants can structure associated arthropod and microbial communities, but whether the effects are consistent and repeatable across years is unknown. If communities are both heritable (i.e., related individuals tend to support similar communities) and repeatable (i.e., the same patterns observed over multiple years), then plant genetics may also affect community properties previously thought to be emergent, such as "stability." Using replicated clones of narrowleaf cottonwood (Populus angustifolia) and examining an arthropod community of 103 species, we found that (1) individual tree genotypes supported significantly different arthropod communities, which exhibited broad-sense heritability; (2) these findings were highly repeatable over three consecutive years (repeatability = 0.91) indicating that community responses to individual tree genotypes are consistent from year to year; (3) differences among tree genotypes in community stability (i.e., changes in community composition over multiple years) exhibited broad-sense heritability (H(C)2 = 0.32). In combination, these findings suggest that an emergent property such as stability can be genetically based and thus subject to natural selection.

VL - 91 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=21141200&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 11 ER - TY - JOUR T1 - From genes to ecosystems: a synthesis of the effects of plant genetic factors across levels of organization. JF - Philosophical transactions of the Royal Society of London. Series B, Biological sciences Y1 - 2009 A1 - JK Bailey A1 - Jennifer A Schweitzer A1 - Ubeda,Francisco A1 - Koricheva,Julia A1 - LeRoy,Carri J A1 - Madritch,Michael D A1 - Rehill,Brian J A1 - RK Bangert A1 - Fischer,Dylan G A1 - Allan,Gerard J A1 - Whitham,Thomas G KW - Animals KW - Arthropods KW - Ecosystem KW - Genetic Variation KW - Genetics, Population KW - Models, Genetic KW - Plant Development KW - Plants AB -

Using two genetic approaches and seven different plant systems, we present findings from a meta-analysis examining the strength of the effects of plant genetic introgression and genotypic diversity across individual, community and ecosystem levels with the goal of synthesizing the patterns to date. We found that (i) the strength of plant genetic effects can be quite high; however, the overall strength of genetic effects on most response variables declined as the levels of organization increased. (ii) Plant genetic effects varied such that introgression had a greater impact on individual phenotypes than extended effects on arthropods or microbes/fungi. By contrast, the greatest effects of genotypic diversity were on arthropods. (iii) Plant genetic effects were greater on above-ground versus below-ground processes, but there was no difference between terrestrial and aquatic environments. (iv) The strength of the effects of intraspecific genotypic diversity tended to be weaker than interspecific genetic introgression. (v) Although genetic effects generally decline across levels of organization, in some cases they do not, suggesting that specific organisms and/or processes may respond more than others to underlying genetic variation. Because patterns in the overall impacts of introgression and genotypic diversity were generally consistent across diverse study systems and consistent with theoretical expectations, these results provide generality for understanding the extended consequences of plant genetic variation across levels of organization, with evolutionary implications.

VL - 364 SN - 0962-8436 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=19414474&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1523 ER - TY - JOUR T1 - Genetic and environmental controls of microbial communities on leaf litter in streams . JF - Freshwater Biology Y1 - 2009 A1 - Marks,JC A1 - Haden,GA A1 - Harrop,BA A1 - Reese,EG A1 - Keams,JL A1 - Watwood,ME A1 - TG Whitham VL - 54 N1 - [Original String]:Marks JC, Haden GA, Harrop BA, Reese EG, Keams JL, Watwood ME, Whitham TG. 2009. Genetic and environmental controls of microbial communities on leaf litter in streams . Freshwater Biology 54:2616-2627. ER - TY - JOUR T1 - Genetic basis of aboveground productivity in two native Populus species and their hybrids. JF - Tree physiology Y1 - 2009 A1 - Lojewski,Nathan R A1 - Fischer,Dylan G A1 - JK Bailey A1 - Jennifer A Schweitzer A1 - Whitham,Thomas G A1 - Stephen C Hart KW - Ecosystem KW - Genotype KW - Hybridization, Genetic KW - Populus KW - Species Specificity KW - Utah AB -

Demonstration of genetic control over riparian tree productivity has major implications for responses of riparian systems to shifting environmental conditions and effects of genetics on ecosystems in general. We used field studies and common gardens, applying both molecular and quantitative techniques, to compare plot-level tree aboveground net primary productivity (ANPP(tree)) and individual tree growth rate constants in relation to plant genetic identity in two naturally occurring Populus tree species and their hybrids. In field comparisons of four cross types (Populus fremontii S. Wats., Populus angustifolia James, F(1) hybrids and backcross hybrids) across 11 natural stands, productivity was greatest for P. fremontii trees, followed by hybrids and lowest in P. angustifolia. A similar pattern was observed in four common gardens across a 290 m elevation and 100 km environmental gradient. Despite a doubling in productivity across the common gardens, the relative differences among the cross types remained constant. Using clonal replicates in a common garden, we found ANPP(tree) to be a heritable plant trait (i.e., broad-sense heritability), such that plant genetic factors explained between 38% and 82% of the variation in ANPP(tree). Furthermore, analysis of the genetic composition among individual tree genotypes using restriction fragment length polymorphism molecular markers showed that genetically similar trees also exhibited similar ANPP(tree). These findings indicate strong genetic contributions to natural variation in ANPP with important ecological implications.

VL - 29 SN - 0829-318X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=19578030&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 9 ER - TY - JOUR T1 - Genetically based susceptibility to herbivory influences the ectomycorrhizal fungal communities of a foundation tree species. JF - The New phytologist Y1 - 2009 A1 - Sthultz,Christopher M A1 - Whitham,Thomas G A1 - Kennedy,Karla A1 - Deckert,Ron A1 - Gehring,Catherine A KW - Animals KW - DNA, Fungal KW - Ecosystem KW - Host-Pathogen Interactions KW - Models, Biological KW - Moths KW - Mycorrhizae KW - Pinus KW - Symbiosis AB -

Although recent research indicates that herbivores interact with plant-associated microbes in complex ways, few studies have examined these interactions using a community approach. For example, the impact of herbivory on the community structure of ectomycorrhizal fungi (EMF) is not well known. The influence of host plant genetics on EMF community composition is also poorly understood. We used a study system in which susceptibility to herbivory has a genetic basis and a 20-yr insect removal experiment to examine the influence of chronic herbivory and plant genetics on the EMF community structure of Pinus edulis. We compared EMF communities of herbivore resistant trees, herbivore susceptible trees and herbivore susceptible trees from which herbivores were experimentally removed at two dates 10 yr apart. In both years sampled, resistant and susceptible trees differed significantly in EMF community composition. After 10 yr and 20 yr of herbivore removal, the EMF communities of removal trees were similar to those of susceptible trees, but different from resistant trees. The EMF community composition was more strongly influenced by innate genetic differences in plant traits associated with resistance and susceptibility to herbivory than by indirect effects of herbivory on host plant relationships with ectomycorrhizal fungi.

VL - 184 SN - 0028-646X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=19761493&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 3 ER - TY - JOUR T1 - A geographic mosaic of genetic variation within a foundation tree species and its community-level consequences. JF - Ecology Y1 - 2009 A1 - Barbour,Robert C A1 - O'Reilly-Wapstra,Julianne M A1 - De Little,David W A1 - Jordan,Gregory J A1 - Steane,Dorothy A A1 - Humphreys,Jonathon R A1 - JK Bailey A1 - Whitham,Thomas G A1 - Potts,Bradley M KW - Animals KW - Australia KW - Biological Evolution KW - Demography KW - Ecosystem KW - Eucalyptus KW - Fungi KW - Genetic Variation KW - Insecta AB -

Knowledge of the manner in which genetic variation within a tree species affects associated communities and ecosystem processes across its entire range is important for understanding how geographic mosaics of genetic interactions might develop and support different communities. While numerous studies have investigated the community and ecosystem consequences of genetic variation at the hybrid cross type or genotype level within a species, none has investigated the community-level effects of intraspecific genetic variation across the geographic range of a widespread species. This is the scale at which geographic mosaics of coevolution are hypothesized to exist. Studies at this level are particularly important for foundation tree species, which typically support numerous microbial, fungal, plant, and animal communities. We studied genetic variation across eight geographical races of the forest tree Eucalyptus globulus representing its natural distribution across southeastern Australia. The study was conducted in a 15-year-old common garden trial based on families derived from single-tree open-pollinated seed collections from the wild. Neutral molecular genetic variation within E. globulus was also assessed and compared with genetic divergence in the phenotypic and community traits. Three major findings emerged. First, we found significant genetically based, hierarchical variation in associated communities corresponding to geographical races of E. globulus and families within races. Second, divergence in foliar communities at the racial level was associated with genetically based divergence in specific leaf morphological and chemical traits that have known defensive functions. Third, significant positive correlations between canopy community dissimilarity and both neutral molecular genetic and leaf quantitative genetic dissimilarity at the race level supported a genetic similarity rule. Our results argue that genetic variation within foundation tree species has the potential to be a significant driver of the geographical mosaics of variation typical of forest communities, which could have important ecological and evolutionary implications.

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=19694126&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 7 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 - TY - JOUR T1 - A dense linkage map of hybrid cottonwood (Populus fremontii x P. angustifolia) contributes to long-term ecological research and comparison mapping in a model forest tree. JF - Heredity Y1 - 2008 A1 - Woolbright,S A A1 - Difazio,S P A1 - Yin,T A1 - Martinsen,G D A1 - Zhang,X A1 - Allan,G J A1 - Whitham,T G A1 - Keim,P KW - Chimera KW - Chromosome Mapping KW - Ecology KW - Genetic Linkage KW - Genetic Markers KW - Genetics, Population KW - Genome, Plant KW - Linkage Disequilibrium KW - Models, Biological KW - Polymorphism, Restriction Fragment Length KW - Populus KW - Trees AB -

Cottonwoods are foundation riparian species, and hybridization among species is known to produce ecological effects at levels higher than the population, including effects on dependent species, communities and ecosystems. Because these patterns result from increased genetic variation in key cottonwood traits, novel applications of genetic tools (for example, QTL mapping) could be used to place broad-scale ecological research into a genomic perspective. In addition, linkage maps have been produced for numerous species within the genus, and, coupled with the recent publication of the Populus genome sequence, these maps present a unique opportunity for genome comparisons in a model system. Here, we conducted linkage analyses in order to (1) create a platform for QTL and candidate gene studies of ecologically important traits, (2) create a framework for chromosomal-scale perspectives of introgression in a natural population, and (3) enhance genome-wide comparisons using two previously unmapped species. We produced 246 backcross mapping (BC(1)) progeny by crossing a naturally occurring F(1) hybrid (Populus fremontii x P. angustifolia) to a pure P. angustifolia from the same population. Linkage analysis resulted in a dense linkage map of 541 AFLP and 111 SSR markers distributed across 19 linkage groups. These results compared favorably with other Populus linkage studies, and addition of SSR loci from the poplar genome project provided coarse alignment with the genome sequence. Preliminary applications of the data suggest that our map represents a useful framework for applying genomic research to ecological questions in a well-studied system, and has enhanced genome-wide comparisons in a model tree.

VL - 100 SN - 0018-067X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=17895905&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1 ER - TY - JOUR T1 - Extending genomics to natural communities and ecosystems. JF - Science Y1 - 2008 A1 - Whitham,Thomas G A1 - DiFazio,Stephen P A1 - Jennifer A Schweitzer A1 - Shuster,Stephen M A1 - Allan,Gery J A1 - JK Bailey A1 - Woolbright,Scott A KW - Animals KW - Biological Evolution KW - Ecosystem KW - Epigenesis, Genetic KW - Genome, Plant KW - Genomics KW - Plant Physiological Phenomena KW - Plants KW - Selection, Genetic KW - Symbiosis AB -

An important step in the integration of ecology and genomics is the progression from molecular studies of relatively simple model systems to complex field systems. The recent availability of sequenced genomes from key plants is leading to a new understanding of the molecular drivers of community composition and ecosystem processes. As genome sequences accumulate for species that form intimate associations in nature, a detailed view may emerge as to how these associations cause changes among species at the nucleotide level. This advance could dramatically alter views about the structure and evolution of communities and ecosystems.

VL - 320 SN - 0036-8075 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=18436780&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 5875 ER - TY - JOUR T1 - From genes to ecosystems: the genetic basis of condensed tannins and their role in nutrient regulation in a Populus model system . JF - Ecosystems Y1 - 2008 A1 - Schweitzer,JA A1 - Madritch,MD A1 - JK Bailey A1 - LeRoy,CJ A1 - Fischer,DG A1 - Rehill,BJ A1 - Lindroth,RL A1 - Hagerman,AE A1 - Wooley,SC A1 - Hart,SC A1 - TG Whitham VL - 11 N1 - [Original String]:Schweitzer JA, Madritch MD, Bailey JK, LeRoy CJ, Fischer DG, Rehill BJ, Lindroth RL, Hagerman AE, Wooley SC, Hart SC, Whitham TG. 2008. From genes to ecosystems: the genetic basis of condensed tannins and their role in nutrient regulation in a Populus model system . Ecosystems 11:1005-1020. ER - TY - JOUR T1 - Genetic structure of a foundation species: scaling community phenotypes from the individual to the region. JF - Heredity Y1 - 2008 A1 - RK Bangert A1 - E V Lonsdorf A1 - Wimp,G M A1 - Shuster,S M A1 - Fischer,D A1 - Schweitzer,J A A1 - Allan,G J A1 - JK Bailey A1 - Whitham,T G KW - Animals KW - biodiversity KW - Ecosystem KW - Environment KW - Populus KW - Trees AB -

Understanding the local and regional patterns of species distributions has been a major goal of ecological and evolutionary research. The notion that these patterns can be understood through simple quantitative rules is attractive, but while numerous scaling laws exist (e.g., metabolic, fractals), we are aware of no studies that have placed individual traits and community structure together within a genetics based scaling framework. We document the potential for a genetic basis to the scaling of ecological communities, largely based upon our long-term studies of poplars (Populus spp.). The genetic structure and diversity of these foundation species affects riparian ecosystems and determines a much larger community of dependent organisms. Three examples illustrate these ideas. First, there is a strong genetic basis to phytochemistry and tree architecture (both above- and belowground), which can affect diverse organisms and ecosystem processes. Second, empirical studies in the wild show that the local patterns of genetics based community structure scale up to western North America. At multiple spatial scales the arthropod community phenotype is related to the genetic distance among plants that these arthropods depend upon for survival. Third, we suggest that the familiar species-area curve, in which species richness is a function of area, is also a function of genetic diversity. We find that arthropod species richness is closely correlated with the genetic marker diversity and trait variance suggesting a genetic component to these curves. Finally, we discuss how genetic variation can interact with environmental variation to affect community attributes across geographic scales along with conservation implications.

VL - 100 SN - 0018-067X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=17047690&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 2 ER - TY - JOUR T1 - Plant-soil microorganism interactions: heritable relationship between plant genotype and associated soil microorganisms. JF - Ecology Y1 - 2008 A1 - Jennifer A Schweitzer A1 - JK Bailey A1 - Fischer,Dylan G A1 - LeRoy,Carri J A1 - Lonsdorf,Eric V A1 - Whitham,Thomas G A1 - Stephen C Hart KW - Biomass KW - Crosses, Genetic KW - Ecosystem KW - Fatty Acids KW - Genetic Variation KW - Genotype KW - Host-Pathogen Interactions KW - Phospholipids KW - Plants KW - Soil Microbiology KW - Species Specificity AB -

Although soil microbial communities are known to play crucial roles in the cycling of nutrients in forest ecosystems and can vary by plant species, how microorganisms respond to the subtle gradients of plant genetic variation is just beginning to be appreciated. Using a model Populus system in a common garden with replicated clones of known genotypes, we evaluated microbial biomass and community composition as quantitative traits. Two main patterns emerged. (1) Plant genotype influenced microbial biomass nitrogen in soils under replicated genotypes of Populus angustifolia, F1, and backcross hybrids, but not P. fremontii. Genotype explained up to 78% of the variation in microbial biomass as indicated by broad-sense heritability estimates (i.e., clonal repeatability). A second estimate of microbial biomass (total phospholipid fatty acid) was more conservative and showed significant genotype effects in P. angustifolia and backcross hybrids. (2) Plant genotype significantly influenced microbial community composition, explaining up to 70% of the variation in community composition within P. angustifolia genotypes alone. These findings suggest that variation in above- and belowground traits of individual plant genotypes can alter soil microbial dynamics, and suggests that further investigations of the evolutionary implications of genetic feedbacks are warranted.

VL - 89 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=18459340&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 3 ER - TY - JOUR T1 - Tree hybridization and genotypic variation drive cryptic speciation of a specialist mite herbivore. JF - Evolution; international journal of organic evolution Y1 - 2008 A1 - Evans,Luke M A1 - Allan,Gerard J A1 - Shuster,Stephen M A1 - Woolbright,Scott A A1 - Whitham,Thomas G KW - Analysis of Variance KW - Animals KW - Base Sequence KW - Cluster Analysis KW - Crosses, Genetic KW - DNA Primers KW - Genetic Variation KW - Genetics, Population KW - Geography KW - Host-Parasite Interactions KW - Hybridization, Genetic KW - Mites KW - Molecular Sequence Data KW - Phylogeny KW - Populus KW - Sequence Analysis, DNA KW - Utah AB -

Few studies have investigated the roles that plant hybridization and individual plant genotype play in promoting population divergence within arthropod species. Using nrDNA sequence information and reciprocal transfer experiments, we examined how tree cross type (i.e., pure Populus angustifolia and P. angustifolia x P. fremontii F(1) type hybrids) and individual tree genotype influence host race formation in the bud-galling mite Aceria parapopuli. Three main findings emerged: (1) Strong genetic differentiation of mite populations found on pure P. angustifolia and F(1) type hybrids indicates that these mites represent morphologically cryptic species. (2) Within the F(1) type hybrids, population genetic analyses indicate migration among individual trees; however, (3) transfer experiments show that the mites found on heavily infested F(1) type trees perform best on their natal host genotype, suggesting that genetic interactions between mites and their host trees drive population structure, local adaptation, and host race formation. These findings argue that hybridization and genotypic differences in foundation tree species may drive herbivore population structure, and have evolutionary consequences for dependent arthropod species.

VL - 62 SN - 0014-3820 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=18752612&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 12 ER - TY - JOUR T1 - Genetic assembly rules and community phenotypes JF - Evolutionary Ecology Y1 - 2007 A1 - TG Whitham A1 - RK Bangert VL - 21 UR - http://www.bioone.org/servlet/linkout?suffix=bibr04&dbid=16&doi=10.2980%2F19-1-3402&key=10.1007%2Fs10682-006-9135-7 IS - 4 ER - TY - JOUR T1 - Genetic‐based plant resistance and susceptibility traits to herbivory influence needle and root litter nutrient dynamics JF - Journal of Ecology Y1 - 2007 A1 - Classen,AT A1 - Chapman,SK A1 - TG Whitham A1 - Hart,SC A1 - GW Koch AB - Summary 1 It is generally assumed that the same factors drive the decomposition of both litter and roots and that nutrient release from litter and roots is synchronized. However, few studies have explicitly tested these assumptions, and no studies have examined whether plant genetics (i.e. plant susceptibility to herbivory) could affect these relationships. 2 Here we examine the effects of herbivore susceptibility and resistance on needle and fine root litter decomposition of pi帽on pine, Pinus edulis . The study population consists of individual trees that are either susceptible or resistant to herbivory by the pi帽on needle scale, Matsucoccus acalyptus , or the stem-boring moth, Dioryctria albovittella . Genetic analyses and long-term experimental removals and additions of these insects to individual trees have identified trees that are naturally resistant or susceptible to M. acalyptus and D. albovittella . In addition, these herbivores increase litter chemical quality and alter soil microclimate, both of which mediate decomposition in ecosystems. 3 The effects of herbivore susceptibility and resistance on needle litter mass and phosphorus (P) loss, when significant, are largely mediated by herbivore-induced changes to microclimate. But the effects of herbivore susceptibility and resistance on root litter nitrogen (N) and P retention, and needle litter N retention, are largely governed by herbivore-induced changes to litter chemical quality. Whether a particular tree was resistant or susceptible to herbivores exerted a large influence on net nutrient release, but the direction of herbivore influence varied temporally. 4 The controls on decomposition vary between herbivore-susceptible and herbivore-resistant phenotypes. This suggests that understanding decomposition and nutrient retention in some ecosystems may require considering the effects of herbivores on above- and below-ground processes and how these effects may be governed by plant genetics. 5 Synthesis . Because so few studies have attempted to quantify genetic components of ecosystem processes, the integration of ecosystem ecology with population genetics has the potential to place ecosystem science within a genetic and evolutionary framework. Using field trials of known genetic composition, ecosystem scientists may use quantitative genetics techniques to explore ecosystem traits just as population geneticists have used these techniques to explore traditional traits such as resistance to insects. VL - 95 UR - http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2745.2007.01297.x/full IS - 6 ER - TY - CHAP T1 - Host plants mediate ant-aphid mutualisms and their effects on community structure and diversity T2 - Ecological communities: plant mediation in indirect interaction webs. Y1 - 2007 A1 - Wimp,GM A1 - TG Whitham ED - Ohgushi,T ED - Craig,TP ED - Price,PW JF - Ecological communities: plant mediation in indirect interaction webs. PB - Cambridge University Press CY - New York, NY, USA ER - TY - JOUR T1 - Plant genetics predicts intra-annual variation in phytochemistry and arthropod community structure. JF - Molecular ecology Y1 - 2007 A1 - Wimp,G M A1 - Wooley,S A1 - RK Bangert A1 - Young,W P A1 - Martinsen,G D A1 - Keim,P A1 - Rehill,B A1 - R L Lindroth A1 - Whitham,T G KW - Animals KW - Arthropods KW - DNA, Plant KW - Ecosystem KW - Genetics, Population KW - Plant Extracts KW - Polymorphism, Restriction Fragment Length KW - Population Density KW - Population Dynamics KW - Populus KW - Seasons AB -

With the emerging field of community genetics, it is important to quantify the key mechanisms that link genetics and community structure. We studied cottonwoods in common gardens and in natural stands and examined the potential for plant chemistry to be a primary mechanism linking plant genetics and arthropod communities. If plant chemistry drives the relationship between plant genetics and arthropod community structure, then several predictions followed. We would find (i) the strongest correlation between plant genetic composition and chemical composition; (ii) an intermediate correlation between plant chemical composition and arthropod community composition; and (iii) the weakest relationship between plant genetic composition and arthropod community composition. Our results supported our first prediction: plant genetics and chemistry had the strongest correlation in the common garden and the wild. Our results largely supported our second prediction, but varied across space, seasonally, and according to arthropod feeding group. Plant chemistry played a larger role in structuring common garden arthropod communities relative to wild communities, free-living arthropods relative to leaf and stem modifiers, and early-season relative to late-season arthropods. Our results did not support our last prediction, as host plant genetics was at least as tightly linked to arthropod community structure as plant chemistry, if not more so. Our results demonstrate the consistency of the relationship between plant genetics and biodiversity. Additionally, plant chemistry can be an important mechanism by which plant genetics affects arthropod community composition, but other genetic-based factors are likely involved that remain to be measured.

VL - 16 SN - 0962-1083 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=17927708&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 23 ER - TY - JOUR T1 - Within-species variation in foliar chemistry influences leaf-litter decomposition in a Utah river . JF - Journal of The North American Benthological Society Y1 - 2007 A1 - LeRoy,CJ A1 - TG Whitham A1 - Wooley,SC A1 - Marks,JC VL - 26 IS - 3 N1 - [Original String]:LeRoy CJ, Whitham TG, Wooley SC, Marks JC. 2007. Within-species variation in foliar chemistry influences leaf-litter decomposition in a Utah river . Journal of The North American Benthological Society 26(3):426-438. ER - TY - JOUR T1 - Community heritability measures the evolutionary consequences of indirect genetic effects on community structure. JF - Evolution; international journal of organic evolution Y1 - 2006 A1 - Shuster,S M A1 - E V Lonsdorf A1 - Wimp,G M A1 - JK Bailey A1 - Whitham,T G KW - Animals KW - Arthropods KW - Computer Simulation KW - Environment KW - Evolution, Molecular KW - Genetic Variation KW - North America KW - Phenotype KW - Populus KW - Selection, Genetic KW - Trees AB -

The evolutionary analysis of community organization is considered a major frontier in biology. Nevertheless, current explanations for community structure exclude the effects of genes and selection at levels above the individual. Here, we demonstrate a genetic basis for community structure, arising from the fitness consequences of genetic interactions among species (i.e., interspecific indirect genetic effects or IIGEs). Using simulated and natural communities of arthropods inhabiting North American cottonwoods (Populus), we show that when species comprising ecological communities are summarized using a multivariate statistical method, nonmetric multidimensional scaling (NMDS), the resulting univariate scores can be analyzed using standard techniques for estimating the heritability of quantitative traits. Our estimates of the broad-sense heritability of arthropod communities on known genotypes of cottonwood trees in common gardens explained 56-63% of the total variation in community phenotype. To justify and help interpret our empirical approach, we modeled synthetic communities in which the number, intensity, and fitness consequences of the genetic interactions among species comprising the community were explicitly known. Results from the model suggest that our empirical estimates of broad-sense community heritability arise from heritable variation in a host tree trait and the fitness consequences of IGEs that extend from tree trait to arthropods. When arthropod traits are heritable, interspecific IGEs cause species interactions to change, and community evolution occurs. Our results have implications for establishing the genetic foundations of communities and ecosystems.

VL - 60 SN - 0014-3820 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=16817539&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 5 ER - TY - JOUR T1 - Developmental trajectories in cottonwood phytochemistry. JF - Journal of chemical ecology Y1 - 2006 A1 - Rehill,Brian J A1 - Whitham,Thomas G A1 - Martinsen,Gregory D A1 - Jennifer A Schweitzer A1 - JK Bailey A1 - Lindroth,Richard L KW - Crosses, Genetic KW - Glucosides KW - Least-Squares Analysis KW - Nitrogen KW - Phenols KW - Populus KW - Proanthocyanidins AB -

We examined the hypothesis that ecologically important phytochemical traits differ predictably among various developmental zones of trees (i.e., mature and juvenile zones of individual trees and juvenile ramets that sprout from roots) and that the slope of this phytochemical gradient represents a "developmental trajectory." We focused on Populus fremontii (Fremont cottonwood), P. angustifolia (narrowleaf cottonwood), and their natural hybrids. Two major patterns emerged. First, within narrowleaf and hybrids, concentrations of important phytochemicals (condensed tannins and phenolic glycosides) differ greatly and predictably between developmental zones. Second, developmental trajectories differ greatly among these cottonwood species and their hybrids: Fremont exhibits a flat trajectory, narrowleaf a steep trajectory, and hybrids an intermediate trajectory, suggesting an additive genetic component and an ontogenetic basis to this phytochemical variation. Because diverse herbivorous species respond to the phytochemistry of their host plants, we predict that the developmental trajectories of plants play a major role in mediating ecological interactions and structuring communities, and that biodiversity in a stand of trees is determined by both interplant genetic diversity and intraplant ontogenetic diversity.

VL - 32 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=17001533&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 10 ER - TY - JOUR T1 - Do high-tannin leaves require more roots? JF - Oecologia Y1 - 2006 A1 - Fischer,FG A1 - Hart,SC A1 - Rehill,BJ A1 - Lindroth,RL A1 - Keim,P A1 - and Whitham,TG VL - 149 IS - 4 ER - TY - JOUR T1 - Environmental and genetic effects on the formation of ectomycorrhizal and arbuscular mycorrhizal associations in cottonwoods. JF - Oecologia Y1 - 2006 A1 - Gehring,Catherine A A1 - Mueller,Rebecca C A1 - Whitham,Thomas G KW - Altitude KW - Carbon KW - Hybridization, Genetic KW - Mycorrhizae KW - Nitrogen KW - Polymorphism, Restriction Fragment Length KW - Populus KW - Soil KW - Symbiosis KW - Utah KW - Water AB -

Although both environment and genetics have been shown to affect the mycorrhizal colonization of host plants, the impacts of these factors on hosts that can be dually colonized by both ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) fungi are less understood. We examined the influence of environment and host crosstype on the EM and AM colonization of cottonwoods (Populus angustifolia and natural hybrids) by comparing levels of colonization of trees growing in common gardens that differed in elevation and soil type. We also conducted a supplemental watering experiment to determine the influence of soil moisture on AM and EM colonization. Three patterns emerged. First, garden location had a significant impact on mycorrhizal colonization, such that EM colonization was 30% higher and AM colonization was 85% lower in the higher elevation garden than the lower elevation garden. Second, crosstype affected total (EM + AM) colonization, but did not affect EM or AM colonization. Similarly, a significant garden x crosstype interaction was found for total colonization, but not for EM or AM colonization. Third, experimental watering resulted in 33% higher EM colonization and 45% lower AM colonization, demonstrating that soil moisture was a major driver of the mycorrhizal differences observed between the gardens. We conclude that environment, particularly soil moisture, has a larger influence on colonization by AM versus EM fungi than host genetics, and suggest that environmental stress may be a major determinant of mycorrhizal colonization in dually colonized host plants.

VL - 149 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=16642319&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1 ER - TY - JOUR T1 - A framework for community and ecosystem genetics: from genes to ecosystems. JF - Nature reviews. Genetics Y1 - 2006 A1 - Whitham,Thomas G A1 - JK Bailey A1 - Jennifer A Schweitzer A1 - Shuster,Stephen M A1 - RK Bangert A1 - LeRoy,Carri J A1 - Lonsdorf,Eric V A1 - Allan,Gery J A1 - DiFazio,Stephen P A1 - Potts,Brad M A1 - Fischer,Dylan G A1 - Gehring,Catherine A A1 - Lindroth,Richard L A1 - Jane C Marks A1 - Stephen C Hart A1 - Wimp,Gina M A1 - Wooley,Stuart C KW - Animals KW - Ecosystem KW - Genetics, Population KW - Humans KW - Plants AB -

Can heritable traits in a single species affect an entire ecosystem? Recent studies show that such traits in a common tree have predictable effects on community structure and ecosystem processes. Because these 'community and ecosystem phenotypes' have a genetic basis and are heritable, we can begin to apply the principles of population and quantitative genetics to place the study of complex communities and ecosystems within an evolutionary framework. This framework could allow us to understand, for the first time, the genetic basis of ecosystem processes, and the effect of such phenomena as climate change and introduced transgenic organisms on entire communities.

VL - 7 SN - 1471-0056 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=16778835&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 7 ER - TY - JOUR T1 - From genes to geography: a genetic similarity rule for arthropod community structure at multiple geographic scales. JF - Molecular ecology Y1 - 2006 A1 - RK Bangert A1 - Allan,G J A1 - Turek,R J A1 - Wimp,G M A1 - Meneses,N A1 - Martinsen,G D A1 - Keim,P A1 - Whitham,T G KW - Animals KW - Arthropods KW - biodiversity KW - Genetic Variation KW - Genetics, Population KW - Models, Genetic KW - Populus KW - Rivers KW - Southwestern United States AB -

We tested the hypothesis that leaf modifying arthropod communities are correlated with cottonwood host plant genetic variation from local to regional scales. Although recent studies found that host plant genetic composition can structure local dependent herbivore communities, the abiotic environment is a stronger factor than the genetic effect at increasingly larger spatial scales. In contrast to these studies we found that dependent arthropod community structure is correlated with both the cross type composition of cottonwoods and individual genotypes within local rivers up to the regional scale of 720,000 km(2) (Four Corner States region in the southwestern USA). Across this geographical extent comprising two naturally hybridizing cottonwood systems, the arthropod community follows a simple genetic similarity rule: genetically similar trees support more similar arthropod communities than trees that are genetically dissimilar. This relationship can be quantified with or without genetic data in Populus.

VL - 15 SN - 0962-1083 UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=17054514&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 13 ER - TY - JOUR T1 - Importance of species interactions to community heritability: a genetic basis to trophic-level interactions. JF - Ecology letters Y1 - 2006 A1 - JK Bailey A1 - Wooley,Stuart C A1 - Lindroth,Richard L A1 - Whitham,Thomas G KW - Animals KW - Aphids KW - Birds KW - Food Chain KW - Genotype KW - Plant Leaves KW - Populus AB -

Recent community genetics studies have shown that specific genotypes of a host plant support distinct arthropod communities. Building upon these findings, we examined the hypothesis that a trophic community consisting of cottonwood trees, a galling herbivore and avian predators could also be related to the genetics of the host tree. We found genetic correlations among phytochemistry of individual tree genotypes, the density of a galling herbivore, and the intensity of avian predation on these herbivores. We detected significant broad-sense heritability of these interactions that range from H(B)2 = 0.70 to 0.83. The genetic basis of these interactions tended to increase across trophic levels suggesting that small genetic changes in the cottonwood phenotype could have major consequences at higher trophic levels affecting species interactions and energy flow. These findings show a heritable basis to trophic-level interactions indicating that there is a significant genetic basis to community composition and energy flow that is predictable by plant genotype. Our data clearly link plant genetics to patterns of avian foraging and show that species interactions are important components of community heritability and ecosystem processes. Overall, these data support the hypothesis that evolution of plant traits can alter trophic-level interactions and community composition.

VL - 9 SN - 1461-023X UR - http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&DbFrom=pubmed&Cmd=Link&LinkName=pubmed_pubmed&LinkReadableName=Related%20Articles&IdsFromResult=16958871&ordinalpos=3&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSumhttp://www.ncbi. IS - 1 ER -