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1.
Ecology ; : e4395, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39299794

RESUMEN

Plant resource allocation strategies are thought to be largely a consequence of changing abiotic conditions and evolutionary history. However, biotic interactions also influence how a plant allocates resources. As a result, plants mediate indirect interactions between organisms above- and belowground through resource allocation. Neighboring plants can influence plant fitness directly through competition for resources, and indirectly by altering associated community interactions (associational effects), such as pollination, herbivory, and a suite of belowground interactions. Given the importance of community interactions for plant success, and the known ability for plant neighbors to change these interactions, the goal of this "pandemic project" was to understand how heterospecific plant neighbors alter plant resource allocation, whether this occurred through above- or belowground mechanisms, and whether this in turn alters biotic interactions and the relationship between a focal plant and its herbivore and soil community interactions. To do so, we established a common garden experiment, manipulating plant neighbor identity and the extent of interaction among neighbors (aboveground only, vs. above- and belowground interactions, using customized pot types), and measured changes to a focal plant and its biotic interactions over two growing seasons. We found evidence of both neighbor effects and pot type, showing that neighbor interactions affect a focal plant through both above- and belowground processes, and how the focal plant is affected depends on neighbor identity. Though neighbors did not directly alter herbivory or most soil microbial interactions, they did alter the relationship between belowground microbial communities and a plant response trait (specific leaf area). Plant resource allocation responses were reduced with time, showing the importance of extending experiments beyond a single growing season, and are an important consideration when making predictions about plant responses to changing conditions. This study contributes to a growing body of work showing how community contexts affect the above- and belowground interactions of a plant through plant resource allocation strategies.

2.
Cureus ; 16(7): e63749, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39099926

RESUMEN

Adolescents and young adults (AYAs) with cancer are a unique patient population in oncology. An opt-in, secure online survey was conducted among a general population of AYA patients and survivors to better understand the current landscape of AYA cancer. A 28-item online survey was designed for cancer patients and survivors diagnosed between the ages of 18 and 39 years. It comprised questions about demographics, treatment site, clinical trial involvement, support services available, and impact on employment, schooling, and finances. A total of 590 patients registered and 447 (76%) completed the survey. This online exercise was found to be feasible and can serve as an effective method to survey the AYA cancer population.

3.
Ecol Evol ; 14(6): e11440, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38855318

RESUMEN

Species rarity is a common phenomenon across global ecosystems that is becoming increasingly more common under climate change. Although species rarity is often considered to be a stochastic response to environmental and ecological constraints, we examined the hypothesis that plant rarity is a consequence of natural selection acting on performance traits that affect a species range size, habitat specificity, and population aggregation; three primary descriptors of rarity. Using a common garden of 25 species of Tasmanian Eucalyptus, we find that the rarest species have 70% lower biomass than common species. Although rare species demonstrate lower biomass, rare species allocated proportionally more biomass aboveground than common species. There is also a negative phylogenetic autocorrelation underlying the biomass of rare and common species, indicating that traits associated with rarity have diverged within subgenera as a result of environmental factors to reach different associated optima. In support of our hypothesis, we found significant positive relationships between species biomass, range size and habitat specificity, but not population aggregation. These results demonstrate repeated convergent evolution of the trait-based determinants of rarity across the phylogeny in Tasmanian eucalypts. Furthermore, the phylogenetically driven patterns in biomass and biomass allocation seen in rare species may be representative of a larger plant strategy, not yet considered, but offering a mechanism as to how rare species continue to persist despite inherent constraints of small, specialized ranges and populations. These results suggest that if rarity can evolve and is related to plant traits such as biomass, rather than a random outcome of environmental constraints, we may need to revise conservation efforts in these and other rare species to reconsider the abiotic and biotic factors that underlie the distributions of rare plant species.

4.
PLoS One ; 19(5): e0294839, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38768148

RESUMEN

Rare species are often considered inferior competitors due to occupancy of small ranges, specific habitats, and small local populations. However, the phylogenetic relatedness and rarity level (level 1-7 and common) of interacting species in plant-plant interactions are not often considered when predicting the response of rare plants in a biotic context. We used a common garden of 25 species of Tasmanian Eucalyptus, to differentiate non-additive patterns in the biomass of rare versus common species when grown in mixtures varying in phylogenetic relatedness and rarity. We demonstrate that rare species maintain progressively positive non-additive responses in biomass when interacting with phylogenetically intermediate, less rare and common species. This trend is not reflected in common species that out-performed in monocultures compared to mixtures. These results offer predictability as to how rare species' productivity will respond within various plant-plant interactions. However, species-specific interactions, such as those involving E. globulus, yielded a 97% increase in biomass compared to other species-specific interaction outcomes. These results are important because they suggest that plant rarity may also be shaped by biotic interactions, in addition to the known environmental and population factors normally used to describe rarity. Rare species may utilize potentially facilitative interactions with phylogenetically intermediate and common species to escape the effects of limiting similarity. Biotically mediated increases in rare plant biomass may have subsequent effects on the competitive ability and geographic occurrence of rare species, allowing rare species to persist at low abundance across plant communities. Through the consideration of species rarity and evolutionary history, we can more accurately predict plant-plant interaction dynamics to preserve unique ecosystem functions and fundamentally challenge what it means to be "rare".


Asunto(s)
Biomasa , Eucalyptus , Filogenia , Eucalyptus/crecimiento & desarrollo , Eucalyptus/genética , Ecosistema , Evolución Biológica , Especificidad de la Especie , Plantas/clasificación
5.
Nat Microbiol ; 8(12): 2406-2419, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37973868

RESUMEN

Understanding drivers of terrestrial fungal communities over large scales is an important challenge for predicting the fate of ecosystems under climate change and providing critical ecological context for bioengineering plant-microbe interactions in model systems. We conducted an extensive molecular and microscopy field study across the contiguous United States measuring natural variation in the Populus fungal microbiome among tree species, plant niche compartments and key symbionts. Our results show clear biodiversity hotspots and regional endemism of Populus-associated fungal communities explained by a combination of climate, soil and geographic factors. Modelling climate change impacts showed a deterioration of Populus mycorrhizal associations and an increase in potentially pathogenic foliar endophyte diversity and prevalence. Geographic differences among these symbiont groups in their sensitivity to environmental change are likely to influence broader forest health and ecosystem function. This dataset provides an above- and belowground atlas of Populus fungal biodiversity at a continental scale.


Asunto(s)
Micorrizas , Populus , Árboles/microbiología , Ecosistema , Populus/microbiología , Biodiversidad
6.
Commun Biol ; 5(1): 1213, 2022 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357488

RESUMEN

Climate change is having profound effects on species distributions and is likely altering the distribution of genetic variation across landscapes. Maintaining population genetic diversity is essential for the survival of species facing rapid environmental change, and variation loss will further ecological and evolutionary change. We used trait values of spring foliar leaf-out phenology of 400 genotypes from three geographically isolated populations of Populus angustifolia grown under common conditions, in concert with stacked species distribution modeling, to ask: (a) How will climate change alter phenological variation across the P. angustifolia species-range, and within populations; and (b) will the distribution of phenological variation among and within populations converge (become more similar) in future climatic conditions? Models predicted a net loss of phenological variation in future climate scenarios on 20-25% of the landscape across the species' range, with the trailing edge population losing variation on as much as 47% of the landscape. Our models also predicted that population's phenological trait distributions will become more similar over time. This stacked distribution model approach allows for the identification of areas expected to experience the greatest loss of genetically based functional trait variation and areas that may be priorities to conserve as future genetic climate refugia.


Asunto(s)
Cambio Climático , Populus , Hojas de la Planta/genética , Estaciones del Año , Populus/genética , Fenotipo
7.
Pediatr Blood Cancer ; 69(11): e29962, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36094384

RESUMEN

INTRODUCTION: The risk of human papillomavirus (HPV)-associated cancers is significantly higher among survivors of a childhood cancer compared to the general population. Despite this, their HPV vaccine uptake rates are lower. We examined factors related to HPV vaccine uptake among childhood cancer survivors from Western New York over 13 years following the introduction of HPV vaccines. METHODS: Retrospective review of patients diagnosed with invasive or noninvasive cancerous conditions at age 9 or younger treated at Roswell Park Oishei Children's Cancer and Blood Disorder Program. We matched vaccine date information for patients aged 9-26 years between 2006 and 2020 from the New York State Immunization Information System. Demographic and cancer-related information was abstracted from electronic medical records. Cumulative vaccine uptake was assessed by Kaplan-Meier and Cox proportional hazards regression models. RESULTS: A total of 284 patients were included in the analyses. Most were non-Hispanic/White (80.3%) and resided in a metropolitan area (81.7%). Approximately half had leukemia or lymphoma (54.9%), and most received chemotherapy. Females were more likely to initiate the HPV vaccine and did so sooner (median = 5.5 years) than males (median = 5.7 years; log-rank p = .301). Patients who were older at vaccine eligibility and males who received blood product transfusions were significantly less likely to initiate the HPV vaccine. CONCLUSION: While rates of HPV vaccine initiation have been increasing with time among childhood cancer survivors, they remain low overall, with differences seen by treatment and diagnosis. Our findings support the need for further research to optimize HPV vaccine delivery in cancer care.


Asunto(s)
Alphapapillomavirus , Supervivientes de Cáncer , Neoplasias , Infecciones por Papillomavirus , Vacunas contra Papillomavirus , Niño , Femenino , Humanos , Masculino , Neoplasias/tratamiento farmacológico , New York/epidemiología , Infecciones por Papillomavirus/prevención & control , Vacunas contra Papillomavirus/uso terapéutico , Vacunación
8.
PLoS One ; 17(9): e0274892, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36121872

RESUMEN

Identifying and predicting how species ranges will shift in response to climate change is paramount for conservation and restoration. Ecological niche models are the most common method used to estimate potential distributions of species; however, they traditionally omit knowledge of intraspecific variation that can allow populations to respond uniquely to change. Here, we aim to test how population X environment relationships influence predicted suitable geographic distributions by comparing aggregated population-level models with species-level model predictions of suitable habitat within population ranges and across the species' range. We also test the effect of two variable selection methods on these predictions-both addressing the possibility of local adaptation: Models were built with (a) a common set, and number, of predictors and, (b) a unique combination and number of predictors specific to each group's training extent. Our study addresses the overarching hypothesis that populations have unique environmental niches, and specifically that (1) species-level models predict more suitable habitat within the ranges of genetic populations than individual models built from those groups, particularly when compared models are built with the same set of environmental predictors; and (2) aggregated genetic population models predict more suitable habitat across the species' range than the species-level model, an = d this difference will increase when models are trained with individualized predictors. We found the species models predicted more habitat within population ranges for two of three genetic groups regardless of variable selection, and that aggregated population models predicted more habitat than species' models, but that individualized predictors increased this difference. Our study emphasizes the extent to which changes to model predictions depend on the inclusion of genetic information and on the type and selection of predictors. Results from these modeling decisions can have broad implications for predicting population-level ecological and evolutionary responses to climate change.


Asunto(s)
Ecosistema , Árboles , Aclimatación , Adaptación Fisiológica , Cambio Climático
9.
Trends Ecol Evol ; 37(11): 1006-1019, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35995606

RESUMEN

Research on the evolutionary ecology of urban areas reveals how human-induced evolutionary changes affect biodiversity and essential ecosystem services. In a rapidly urbanizing world imposing many selective pressures, a time-sensitive goal is to identify the emergent issues and research priorities that affect the ecology and evolution of species within cities. Here, we report the results of a horizon scan of research questions in urban evolutionary ecology submitted by 100 interdisciplinary scholars. We identified 30 top questions organized into six themes that highlight priorities for future research. These research questions will require methodological advances and interdisciplinary collaborations, with continued revision as the field of urban evolutionary ecology expands with the rapid growth of cities.


Asunto(s)
Ecosistema , Urbanización , Biodiversidad , Ciudades , Ecología/métodos , Humanos
10.
New Phytol ; 232(2): 762-775, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34227117

RESUMEN

Identifying the potential for natural soil microbial communities to predictably affect complex plant traits is an important frontier in climate change research. Plant phenology varies with environmental and genetic factors, but few studies have examined whether the soil microbiome interacts with plant population differentiation to affect phenology and ecosystem function. We compared soil microbial variation in a widespread tree species (Populus angustifolia) with different soil inoculum treatments in a common garden environment to test how the soil microbiome affects spring foliar phenology and subsequent biomass growth. We hypothesized and show that soil bacterial and fungal communities vary with tree conditioning from different populations and elevations, that this soil community variation influences patterns of foliar phenology and plant growth across populations and elevation gradients, and that transferring lower elevation plant genotypes to higher elevation soil communities delayed foliar phenology, thereby shortening the growing season and reducing annual biomass production. Our findings show the importance of plant-soil interactions that help shape the timing of tree foliar phenology and productivity. These geographic patterns in plant population × microbiome interactions also broaden our understanding of how soil communities impact plant phenotypic variation across key climate change gradients, with consequences for ecosystem functioning.


Asunto(s)
Microbiota , Populus , Cambio Climático , Ecosistema , Estaciones del Año , Suelo
11.
Commun Biol ; 4(1): 748, 2021 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-34135464

RESUMEN

Soil microbiomes are rapidly becoming known as an important driver of plant phenotypic variation and may mediate plant responses to environmental factors. However, integrating spatial scales relevant to climate change with plant intraspecific genetic variation and soil microbial ecology is difficult, making studies of broad inference rare. Here we hypothesize and show: 1) the degree to which tree genotypes condition their soil microbiomes varies by population across the geographic distribution of a widespread riparian tree, Populus angustifolia; 2) geographic dissimilarity in soil microbiomes among populations is influenced by both abiotic and biotic environmental variation; and 3) soil microbiomes that vary in response to abiotic and biotic factors can change plant foliar phenology. We show soil microbiomes respond to intraspecific variation at the tree genotype and population level, and geographic variation in soil characteristics and climate. Using a fully reciprocal plant population by soil location feedback experiment, we identified a climate-based soil microbiome effect that advanced and delayed bud break phenology by approximately 10 days. These results demonstrate a landscape-level feedback between tree populations and associated soil microbial communities and suggest soil microbes may play important roles in mediating and buffering bud break phenology with climate warming, with whole ecosystem implications.


Asunto(s)
Cambio Climático , Ecosistema , Populus/microbiología , Microbiología del Suelo , Suelo/química , Variación Genética , Microbiota , Rizosfera , Árboles/microbiología , Estados Unidos
12.
BMC Cancer ; 21(1): 1, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33397301

RESUMEN

BACKGROUND: This study examined current physical activity levels and preferences for exercise settings and activities among adult survivors of childhood cancers as a strategy to inform the feasibility and design of such programs. METHODS: A mixed-methods design was used to investigate current activity levels as well as barriers to and preferences for physical activity among 20 adult survivors of pediatric cancer. RESULTS: One-half of participants reported engaging in regular physical activity, although the frequency, intensity, and duration varied. Overall, 17 of the 20 participants (85%) stated they would be interested in participating in a structured exercise intervention, and they expressed a strong interest in walking (76%), bicycling (53%), and weight training (53%). Common barriers to participation in a potential structured exercise program were insufficient time, current health issues, and program location/distance. Nearly all participants agreed that information on nutrition and diet should be included as part of an exercise intervention. CONCLUSIONS: These findings will help inform the design and implementation of future exercise programs to enhance physical activity among this high-risk group of cancer survivors.


Asunto(s)
Supervivientes de Cáncer/estadística & datos numéricos , Terapia por Ejercicio , Neoplasias/rehabilitación , Calidad de Vida , Proyectos de Investigación , Adolescente , Adulto , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico , Estudios Retrospectivos , Adulto Joven
13.
Ecol Evol ; 10(9): 3856-3867, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32489616

RESUMEN

Global change is widely altering environmental conditions which makes accurately predicting species range limits across natural landscapes critical for conservation and management decisions. If climate pressures along elevation gradients influence the distribution of phenotypic and genetic variation of plant functional traits, then such trait variation may be informative of the selective mechanisms and adaptations that help define climatic niche limits. Using extensive field surveys along 16 elevation transects and a large common garden experiment, we tested whether functional trait variation could predict the climatic niche of a widespread tree species (Populus angustifolia) with a double quantile regression approach. We show that intraspecific variation in plant size, growth, and leaf morphology corresponds with the species' total climate range and certain climatic limits related to temperature and moisture extremes. Moreover, we find evidence of genetic clines and phenotypic plasticity at environmental boundaries, which we use to create geographic predictions of trait variation and maximum values due to climatic constraints across the western US. Overall, our findings show the utility of double quantile regressions for connecting species distributions and climate gradients through trait-based mechanisms. We highlight how new approaches like ours that incorporate genetic variation in functional traits and their response to climate gradients will lead to a better understanding of plant distributions as well as identifying populations anticipated to be maladapted to future environments.

14.
Plant Environ Interact ; 1(3): 166-180, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37284209

RESUMEN

The objective of this study was to understand how genetic variation in a riparian species, Populus angustifolia, affects mass and energy exchange between the land and atmosphere across ~1,700 km of latitude of the western United States. To examine the potential for large-scale land-atmosphere feedbacks in hydrologic processes driven by geographic differences in plant population traits, we use a physical hydrology model, paired field, and greenhouse observations of plant traits, and stable isotope compositions of soil, stem, and leaf water of P. angustifolia populations. Populations show patterns of local adaptation in traits related to landscape hydrologic functioning-a 47% difference in stomatal density in greenhouse conditions and a 74% difference in stomatal ratio in the field. Trait and stable isotope differences reveal that populations use water differently which is related to historical landscape hydrologic functioning (evapotranspiration and streamflow). Overall, results suggest that populations from landscapes with different hydrologic histories will differ in their ability to maintain favorable water balance with changing atmospheric demands for water, with ecosystem consequences.

15.
Glob Chang Biol ; 25(4): 1514-1528, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30659721

RESUMEN

We examined the hypothesis that climate-driven evolution of plant traits will influence associated soil microbiomes and ecosystem function across the landscape. Using a foundation tree species, Populus angustifolia, observational and common garden approaches, and a base population genetic collection that spans 17 river systems in the western United States, from AZ to MT, we show that (a) as mean annual temperature (MAT) increases, genetic and phenotypic variation for bud break phenology decline; (b) soil microbiomes, soil nitrogen (N), and soil carbon (C) vary in response to MAT and conditioning by trees; and (c) with losses of genetic variation due to warming, population-level regulation of community and ecosystem functions strengthen. These results demonstrate a relationship between the potential evolutionary response of populations and subsequent shifts in ecosystem function along a large temperature gradient.

16.
Nat Ecol Evol ; 2(1): 57-64, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29203921

RESUMEN

Human activity is causing wild populations to experience rapid trait change and local extirpation. The resulting effects on intraspecific variation could have substantial consequences for ecological processes and ecosystem services. Although researchers have long acknowledged that variation among species influences the surrounding environment, only recently has evidence accumulated for the ecological importance of variation within species. We conducted a meta-analysis comparing the ecological effects of variation within a species (intraspecific effects) with the effects of replacement or removal of that species (species effects). We evaluated direct and indirect ecological responses, including changes in abundance (or biomass), rates of ecological processes and changes in community composition. Our results show that intraspecific effects are often comparable to, and sometimes stronger than, species effects. Species effects tend to be larger for direct ecological responses (for example, through consumption), whereas intraspecific effects and species effects tend to be similar for indirect responses (for example, through trophic cascades). Intraspecific effects are especially strong when indirect interactions alter community composition. Our results summarize data from the first generation of studies examining the relative ecological effects of intraspecific variation. Our conclusions can help inform the design of future experiments and the formulation of strategies to quantify and conserve biodiversity.


Asunto(s)
Biodiversidad , Biomasa , Variación Genética , Ecosistema , Modelos Biológicos , Especificidad de la Especie
17.
Nat Ecol Evol ; 1(6): 150, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-28812635

RESUMEN

Plant-soil feedbacks (PSF) are important interactions that may influence range dynamics in a changing world. What remains largely unknown is the generality of plant-soil biotic interactions across populations and the potential role of specific soil biota, both of which are key for understanding how PSF might change future communities and ecosystems. We combined landscape-level field observations and experimental soil treatments to test whether a dominant tree alters soil environments to impact its own performance and range shifts towards higher elevations. We show: (1) soil conditioning by trees varies with elevation, (2) soil biota relate to PSF, (3) under simulated conditions, biotic PSF constrain range shifts at lower elevations but allow for expansions at higher elevations, and (4) differences in soil conditioning predict feedback outcomes in specific range-shift scenarios. These results suggest that variable plant-soil biotic interactions may influence the migration and fragmentation of tree species, and that models incorporating soil parameters will more accurately predict future species distributions.

18.
AoB Plants ; 9(4): plx027, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28721188

RESUMEN

Elevation gradients are frequently used as space-for-time substitutions to infer species' trait responses to climate change. However, studies rarely investigate whether trait responses to elevation are widespread or population-specific within a species, and the relative genetic and plastic contributions to such trait responses may not be well understood. Here, we examine plant trait variation in the dominant woody shrub, Rhododendron maximum, along elevation gradients in three populations in the South Central Appalachian Mountains, USA, in both field and common garden environments. We ask the following: (i) do plant traits vary along elevation? (ii) do trait responses to elevation differ across populations, and if so, why? and (iii) does genetic differentiation or phenotypic plasticity drive trait variation within and among populations? We found that internode length, shoot length, leaf dry mass, and leaf area varied along elevation, but that these responses were generally unique to one population, suggesting that trait responses to environmental gradients are population-specific. A common garden experiment identified no genetic basis to variation along elevation or among populations in any trait, suggesting that plasticity drives local and regional trait variation and may play a key role in the persistence of plant species such as R. maximum with contemporary climate change. Overall, our findings highlight the importance of examining multiple locations in future elevation studies and indicate that, for a given plant species, the magnitude of trait responses to global climate change may vary by location.

19.
Ecology ; 98(8): 2120-2132, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28500764

RESUMEN

Increasing rates of anthropogenic nitrogen (N) enrichment to soils often lead to the dominance of nitrophilic plant species and reduce plant diversity in natural ecosystems. Yet, we lack a framework to predict which species will be winners or losers in soil N enrichment scenarios, a framework that current literature suggests should integrate plant phylogeny, functional tradeoffs, and nutrient co-limitation. Using a controlled fertilization experiment, we quantified biomass responses to N enrichment for 23 forest tree species within the genus Eucalyptus that are native to Tasmania, Australia. Based on previous work with these species' responses to global change factors and theory on the evolution of plant resource-use strategies, we hypothesized that (1) growth responses to N enrichment are phylogenetically structured, (2) species with more resource-acquisitive functional traits have greater growth responses to N enrichment, and (3) phosphorus (P) limits growth responses to N enrichment differentially across species, wherein P enrichment increases growth responses to N enrichment more in some species than others. We built a hierarchical Bayesian model estimating effects of functional traits (specific leaf area, specific stem density, and specific root length) and P fertilization on species' biomass responses to N, which we then compared between lineages to determine whether phylogeny explains variation in responses to N. In concordance with literature on N limitation, a majority of species responded strongly and positively to N enrichment. Mean responses ranged three-fold, from 6.21 (E. pulchella) to 16.87 (E. delegatensis) percent increases in biomass per g N·m-2 ·yr-1 added. We identified a strong difference in responses to N between two phylogenetic lineages in the Eucalyptus subgenus Symphyomyrtus, suggesting that shared ancestry explains variation in N limitation. However, our model indicated that after controlling for phylogenetic non-independence, eucalypt responses to N were not associated with functional traits (although post-hoc analyses show a phylogenetic pattern in specific root length similar to that of responses to N), nor were responses differentially limited by P. Overall, our model results suggest that phylogeny is a powerful predictor of winners and losers in anthropogenic N enrichment scenarios in Tasmanian eucalypts, which may have implications for other species.


Asunto(s)
Biomasa , Filogenia , Plantas/clasificación , Australia , Teorema de Bayes , Ecología , Nitrógeno , Hojas de la Planta , Suelo , Tasmania
20.
J Chem Ecol ; 42(10): 1086-1097, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27577951

RESUMEN

Plants are dependent on their root systems for survival, and thus are defended from belowground enemies by a range of strategies, including plant secondary metabolites (PSMs). These compounds vary among species, and an understanding of this variation may provide generality in predicting the susceptibility of forest trees to belowground enemies and the quality of their organic matter input to soil. Here, we investigated phylogenetic patterns in the root chemistry of species within the genus Eucalyptus. Given the known diversity of PSMs in eucalypt foliage, we hypothesized that (i) the range and concentrations of PSMs and carbohydrates in roots vary among Eucalyptus species, and (ii) that phylogenetic relationships explain a significant component of this variation. To test for interspecific variation in root chemistry and the influence of tree phylogeny, we grew 24 Eucalyptus species representing two subgenera (Eucalyptus and Symphyomyrtus) in a common garden for two years. Fine root samples were collected from each species and analyzed for total phenolics, condensed tannins, carbohydrates, terpenes, and formylated phloroglucinol compounds. Compounds displaying significant interspecific variation were mapped onto a molecular phylogeny and tested for phylogenetic signal. Although all targeted groups of compounds were present, we found that phenolics dominated root defenses and that all phenolic traits displayed significant interspecific variation. Further, these compounds displayed a significant phylogenetic signal. Overall, our results suggest that within these representatives of genus Eucalyptus, more closely related species have more similar root chemistry, which may influence their susceptibility to belowground enemies and soil organic matter accrual.


Asunto(s)
Eucalyptus/química , Eucalyptus/genética , Filogenia , Raíces de Plantas/química , Raíces de Plantas/genética , Carbohidratos/análisis , Fenoles/análisis , Floroglucinol/análisis , Taninos/análisis , Terpenos/análisis
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