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Full-Text Articles in Life Sciences

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby Feb 2024

Toward A Coordinated Understanding Of Hydro-Biogeochemical Root Functions In Tropical Forests For Application In Vegetation Models, Daniela F. Cusack, Bradley Christoffersen, Chris M. Smith-Martin, Kelly M. Andersen, Amanda L. Cordeiro, Katrin Fleischer, S. Joseph Wright, Nathaly R. Guerrero-Ramírez, Laynara F. Lugli, Lindsay A. Mcculloch, Mareli Sanchez-Julia, Sarah A. Batterman, Caroline Dallstream, Claire Fortunel, Laura Toro, Lucia Fuchslueger, Michelle Y. Wong, Daniela Yaffar, Joshua B. Fisher, Marie Arnaud, Lee H. Dietterich, Shalom D. Addo-Danso, Oscar J. Valverde-Barrantes, Monique Weemstra, Jing Cheng Ng, Richard J. Norby

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical forest root characteristics and resource acquisition strategies are underrepresented in vegetation and global models, hampering the prediction of forest–climate feedbacks for these carbon-rich ecosystems. Lowland tropical forests often have globally unique combinations of high taxonomic and functional biodiversity, rainfall seasonality, and strongly weathered infertile soils, giving rise to distinct patterns in root traits and functions compared with higher latitude ecosystems. We provide a roadmap for integrating recent advances in our understanding of tropical forest belowground function into vegetation models, focusing on water and nutrient acquisition. We offer comparisons of recent advances in empirical and model understanding of root characteristics …


Updating The Dual C And O Isotope—Gas-Exchange Model: A Concept To Understand Plant Responses To The Environment And Its Implications For Tree Rings, Rolf T. W. Siegwolf, Marco M. Lehmann, Gregory R. Goldsmith, Olga V. Churakova (Sidorova), Cathleen Mirande-Ney, Galina Timoveeva, Rosmarie B. Weigt, Matthias Saurer Jun 2023

Updating The Dual C And O Isotope—Gas-Exchange Model: A Concept To Understand Plant Responses To The Environment And Its Implications For Tree Rings, Rolf T. W. Siegwolf, Marco M. Lehmann, Gregory R. Goldsmith, Olga V. Churakova (Sidorova), Cathleen Mirande-Ney, Galina Timoveeva, Rosmarie B. Weigt, Matthias Saurer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The combined study of carbon (C) and oxygen (O) isotopes in plant organic matter has emerged as a powerful tool for understanding plant functional responses to environmental change. The approach relies on established relationships between leaf gas exchange and isotopic fractionation to derive a series of model scenarios that can be used to infer changes in photosynthetic assimilation and stomatal conductance driven by changes in environmental parameters (CO2, water availability, air humidity, temperature, nutrients). We review the mechanistic basis for a conceptual model, in light of recently published research, and discuss where isotopic observations do not match our …


Physiological And Transcriptomic Responses Of Two Artemisia Californica Populations To Drought: Implications For Restoring Drought-Resilient Native Communities, Hagop S. Atamian Dr., Jennifer L. Funk Apr 2023

Physiological And Transcriptomic Responses Of Two Artemisia Californica Populations To Drought: Implications For Restoring Drought-Resilient Native Communities, Hagop S. Atamian Dr., Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

As climate change brings drier and more variable rainfall patterns to many arid and semi-arid regions, land managers must re-assemble appropriate plant communities for these conditions. Transcriptome sequencing can elucidate the molecular mechanisms underlying plant responses to changing environmental conditions, potentially enhancing our ability to screen suitable genotypes and species for restoration. We examined physiological and morphological traits and transcriptome sequences of coastal and inland populations of California sagebrush (Artemisia californica), a critical shrub used to restore coastal sage scrub vegetation communities, grown under low and high rainfall environments. The populations are located approximately 36 km apart but …


Technical Note: On Uncertainties In Plant Water Isotopic Composition Following Extraction By Cryogenic Vacuum Distillation, Haoyu Diao, Philipp Schuler, Gregory R. Goldsmith, Rolf T. W. Siegwolf, Matthias Saurer, Marco M. Lehmann Nov 2022

Technical Note: On Uncertainties In Plant Water Isotopic Composition Following Extraction By Cryogenic Vacuum Distillation, Haoyu Diao, Philipp Schuler, Gregory R. Goldsmith, Rolf T. W. Siegwolf, Matthias Saurer, Marco M. Lehmann

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Recent studies have challenged the interpretation of plant water isotopes obtained through cryogenic vacuum distillation (CVD) based on observations of a large 2H fractionation. These studies have hypothesized the existence of an H-atom exchange between water and organic tissue during CVD extraction with the magnitude of H exchange related to relative water content of the sample; however, clear evidence is lacking. Here, we systematically tested the uncertainties in the isotopic composition of CVD-extracted water by conducting a series of incubation and rehydration experiments using isotopically depleted water, water at natural isotope abundance, woody materials with exchangeable H, and organic materials …


Evidence For Phylogenetic Signal And Correlated Evolution In Plant-Water Relations Traits, Eleinis Ávila-Lovera, Klaus Winter, Gregory R. Goldsmith Oct 2022

Evidence For Phylogenetic Signal And Correlated Evolution In Plant-Water Relations Traits, Eleinis Ávila-Lovera, Klaus Winter, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Evolutionary relationships are likely to play a significant role in shaping plant physiological and structural traits observed in contemporary taxa. We review research on phylogenetic signal and correlated evolution in plant-water relations traits, which play important roles in allowing plants to acquire, use and conserve water. We found more evidence for a phylogenetic signal in structural traits (e.g., stomatal length, stomatal density) than in physiological traits (e.g., stomatal conductance, water potential at turgor loss). Although water potential at turgor loss is the most-studied plant-water relations trait in an evolutionary context, it is the only trait consistently found to not have …


Prediction Of Cultivation Areas For The Commercial And An Early Flowering Wild Accession Of Salvia Hispanica L. In The United States, Mohammad Hassani, Thomas Piechota, Hagop S. Atamian Jul 2022

Prediction Of Cultivation Areas For The Commercial And An Early Flowering Wild Accession Of Salvia Hispanica L. In The United States, Mohammad Hassani, Thomas Piechota, Hagop S. Atamian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Salvia hispanica L., commonly known as chia, is a plant-based alternative to seafood and is rich in heart-healthy omega-3 fatty acid, protein, fiber, and antioxidants. In the Northern Hemisphere, chia flowering is triggered by the fall equinox (12-h light and dark, early October) and the seeds mature after approximately three months. Chia is sensitive to frost and end of season moisture which limits its cultivation to small areas in regions with temperate climate. The U.S. chia import has increased considerably over the years; however, chia is not widely cultivated in the United States. This study used the historical U.S. temperature …


Climatic Influences On Summer Use Of Winter Precipitation By Trees, Gregory R. Goldsmith, Scott T. Allen, Sabine Braun, Rolf T. W. Siegwolf, James W. Kirchner May 2022

Climatic Influences On Summer Use Of Winter Precipitation By Trees, Gregory R. Goldsmith, Scott T. Allen, Sabine Braun, Rolf T. W. Siegwolf, James W. Kirchner

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Trees in seasonal climates may use water originating from both winter and summer precipitation. However, the seasonal origins of water used by trees have not been systematically studied. We used stable isotopes of water to compare the seasonal origins of water found in three common tree species across 24 Swiss forest sites sampled in two different years. Water from winter precipitation was observed in trees at most sites, even at the peak of summer, although the relative representation of seasonal sources differed by species. However, the representation of winter precipitation in trees decreased with site mean annual precipitation in both …


Quantifying And Manipulating The Angles Of Light In Experimental Measurements Of Plant Gas Exchange, Z. Carter Berry, Jerry Larue, Gregory R. Goldsmith Mar 2022

Quantifying And Manipulating The Angles Of Light In Experimental Measurements Of Plant Gas Exchange, Z. Carter Berry, Jerry Larue, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Diffuse light has been shown to alter plant leaf photosynthesis, transpiration and water-use efficiency. Despite this, the angular distribution of light for the artificial light sources used with common gas exchange systems is unknown. Here, we quantify the angular distribution of light from common gas exchange systems and demonstrate the use of an integrating sphere for manipulating those light distributions. Among three different systems, light from a 90° angle perpendicular to the leaf surface (±5.75°) was <25% of the total light reaching the leaf surface. The integrating sphere resulted in a greater range of possible distributions from predominantly direct light (i.e., >40% of light from a 90 ± 5.75° angle perpendicular to the leaf surface) to almost entirely diffuse (i.e., light from an even distribution …


Above- And Below-Ground Functional Trait Coordination In The Neotropical Understory Genus Costus, Eleinis Ávila-Lovera, Gregory R. Goldsmith, Kathleen M. Kay, Jennifer L. Funk Dec 2021

Above- And Below-Ground Functional Trait Coordination In The Neotropical Understory Genus Costus, Eleinis Ávila-Lovera, Gregory R. Goldsmith, Kathleen M. Kay, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The study of plant functional traits and variation among and within species can help illuminate functional coordination and trade-offs in key processes that allow plants to grow, reproduce and survive. We studied 20 leaf, above-ground stem, below-ground stem and fine-root traits of 17 Costus species from forests in Costa Rica and Panama to answer the following questions: (i) Do congeneric species show above-ground and below-ground trait coordination and trade-offs consistent with theory of resource acquisition and conservation? (ii) Is there correlated evolution among traits? (iii) Given the diversity of habitats over which Costus occurs, what is the relative contribution of …


Patterns Of Intraspecific Trait Variation Along An Aridity Gradient Suggest Both Drought Escape And Drought Tolerance Strategies In An Invasive Herb, Shana R. Welles, Jennifer L. Funk Sep 2020

Patterns Of Intraspecific Trait Variation Along An Aridity Gradient Suggest Both Drought Escape And Drought Tolerance Strategies In An Invasive Herb, Shana R. Welles, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background and Aims

In water limited landscapes, some plants build structures that enable them to survive with minimal water (drought resistance). Instead of making structures that allow for survival through times of water limitation, annual plants may invoke a drought escape strategy where they complete growth and reproduction when water is available. Drought escape and resistance each require a unique combination of traits and, therefore, plants are likely to have a suite of trait values that are consistent with a single drought response strategy. In environments where conditions are variable, plants may additionally evolve phenotypically plastic trait responses to water …


Leaf Traits Can Be Used To Predict Rates Of Litter Decomposition, Marc Rosenfield, Jennifer L. Funk, Jason K. Keller, Catrina Clausen, Kimberlee Cyphers Jun 2020

Leaf Traits Can Be Used To Predict Rates Of Litter Decomposition, Marc Rosenfield, Jennifer L. Funk, Jason K. Keller, Catrina Clausen, Kimberlee Cyphers

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Strong relationships exist between litter chemistry traits and rates of litter decomposition. However, leaf traits are more commonly found in online trait databases than litter traits and fewer studies have examined how well leaf traits predict litter decomposition rates. Furthermore, while bulk leaf nitrogen (N) content is known to regulate litter decomposition, few studies have explored the importance of N biochemistry fractions, such as protein and amino acid concentration. Here, we decomposed green leaves and naturally senesced leaf litter of nine species representing a wide range of leaf functional traits. We evaluated the ability of traits associated with leaf and …


Leaf Traits And Performance Vary With Plant Age And Water Availability In Artemisia Californica, Jennifer L. Funk, Julie E. Larson, Gregory Vose Jun 2020

Leaf Traits And Performance Vary With Plant Age And Water Availability In Artemisia Californica, Jennifer L. Funk, Julie E. Larson, Gregory Vose

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Background and aims
Leaf functional traits are strongly tied to growth strategies and ecological processes across species, but few efforts have linked intraspecific trait variation to performance across ontogenetic and environmental gradients. Plants are believed to shift towards more resource-conservative traits in stressful environments and as they age. However, uncertainty in how intraspecific trait variation aligns with plant age and performance in the context of environmental variation may limit our ability to use traits to infer ecological processes at larger scales.

Methods
We measured leaf physiological and morphological traits, canopy volume, and flowering effort for Artemisia californica (California sagebrush), a …


De Novo Sequencing And Analysis Of Salvia Hispanica Tissue-Specific Transcriptome And Identification Of Genes Involved In Terpenoid Biosynthesis, James Wimberley, Joseph Cahill, Hagop S. Atamian Mar 2020

De Novo Sequencing And Analysis Of Salvia Hispanica Tissue-Specific Transcriptome And Identification Of Genes Involved In Terpenoid Biosynthesis, James Wimberley, Joseph Cahill, Hagop S. Atamian

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Salvia hispanica (commonly known as chia) is gaining popularity worldwide as a healthy food supplement due to its low saturated fatty acid and high polyunsaturated fatty acid content, in addition to being rich in protein, fiber, and antioxidants. Chia leaves contain plethora of secondary metabolites with medicinal properties. In this study, we sequenced chia leaf and root transcriptomes using the Illumina platform. The short reads were assembled into contigs using the Trinity software and annotated against the Uniprot database. The reads were de novo assembled into 103,367 contigs, which represented 92.8% transcriptome completeness and a diverse set of Gene Ontology …


Ecological Strategies Begin At Germination: Traits, Plasticity, And Survival In The First Four Days Of Plant Life, Julie E. Larson, Brian L. Anacker, Sara Wanous, Jennifer L. Funk Feb 2020

Ecological Strategies Begin At Germination: Traits, Plasticity, And Survival In The First Four Days Of Plant Life, Julie E. Larson, Brian L. Anacker, Sara Wanous, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

  1. We commonly use trait variation to characterize plant function within and among species and understand how vegetation responds to the environment. Seedling emergence is an especially vulnerable window affecting population and community dynamics, yet trait‐based frameworks often bypass this earliest stage of plant life. Here we assess whether traits vary in ecologically‐meaningful ways when seedlings are just days old. How do shared evolutionary history and environmental conditions shape trait expression, and can traits explain which seedlings endure drought?.
  2. We measured seedling traits in the first four days of life for 16 annual plant species under two water treatments, exploring trait …


The 18O-Signal Transfer From Water Vapour To Leaf Water And Assimilates Varies Among Plant Species And Growth Forms, Marco M. Lehmann, Gregory R. Goldsmith, Cathleen Mirande-Ney, Rosemarie B. Weigt, Leonie Schönbeck, Ansgar Kahmen, Arthur Gessler, Rolf T.W. Siegwolf, Matthias Saurer Nov 2019

The 18O-Signal Transfer From Water Vapour To Leaf Water And Assimilates Varies Among Plant Species And Growth Forms, Marco M. Lehmann, Gregory R. Goldsmith, Cathleen Mirande-Ney, Rosemarie B. Weigt, Leonie Schönbeck, Ansgar Kahmen, Arthur Gessler, Rolf T.W. Siegwolf, Matthias Saurer

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The 18O signature of atmospheric water vapour (δ18OV) is known to be transferred via leaf water to assimilates. It remains, however, unclear how the 18O‐signal transfer differs among plant species and growth forms. We performed a 9‐hr greenhouse fog experiment (relative humidity ≥ 98%) with 18O‐depleted water vapour (−106.7‰) on 140 plant species of eight different growth forms during daytime. We quantified the 18O‐signal transfer by calculating the mean residence time of O in leaf water (MRTLW) and sugars (MRTSugars) and related it to leaf traits and physiological …


Diffuse Light And Wetting Differentially Affect Tropical Tree Leaf Photosynthesis, Z. Carter Berry, Gregory R. Goldsmith Aug 2019

Diffuse Light And Wetting Differentially Affect Tropical Tree Leaf Photosynthesis, Z. Carter Berry, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

‐Most ecosystems experience frequent cloud cover resulting in light that is predominantly diffuse rather than direct. Moreover, these cloudy conditions are often accompanied by rain that results in wet leaf surfaces. Despite this, our understanding of photosynthesis is built upon measurements made on dry leaves experiencing direct light.

‐Using a modified gas exchange setup, we measured the effects of diffuse light and leaf wetting on photosynthesis in canopy species from a tropical montane cloud forest.

‐We demonstrate significant variation in species‐level response to light quality independent of light intensity. Some species demonstrated 100% higher rates of photosynthesis in diffuse light …


Estimating Live Fuel Moisture Using Smap L-Band Radiometer Soil Moisture For Southern California, Usa, Shenyue Jia, Seung Hee Kim, Son V. Nghiem, Menas Kafatos Jul 2019

Estimating Live Fuel Moisture Using Smap L-Band Radiometer Soil Moisture For Southern California, Usa, Shenyue Jia, Seung Hee Kim, Son V. Nghiem, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Live fuel moisture (LFM) is a field-measured indicator of vegetation water content and a crucial observation of vegetation flammability. This study presents a new multi-variant regression model to estimate LFM in the Mediterranean ecosystem of Southern California, USA, using the Soil Moisture Active Passive (SMAP) L-band radiometer soil moisture (SMAP SM) from April 2015 to December 2018 over 12 chamise (Adenostoma fasciculatum) LFM sites. The two-month lag between SMAP SM and LFM was utilized either as steps to synchronize the SMAP SM to the LFM series or as the leading time window to calculate the accumulative SMAP SM. …


Purification And Characterization Of A Nonspecific Lipid Transfer Protein 1 (Nsltp1) From Ajwain (Trachyspermum Ammi) Seeds, Meshal Nazeer, Humera Waheed, Maria Saeed, Saman Yousuf Ali, M. Iqbal Choudhary, Zaheer Ul-Haq, Aftab Ahmed Mar 2019

Purification And Characterization Of A Nonspecific Lipid Transfer Protein 1 (Nsltp1) From Ajwain (Trachyspermum Ammi) Seeds, Meshal Nazeer, Humera Waheed, Maria Saeed, Saman Yousuf Ali, M. Iqbal Choudhary, Zaheer Ul-Haq, Aftab Ahmed

Pharmacy Faculty Articles and Research

Ajwain (Trachyspermum ammi) belongs to the family Umbelliferae, is commonly used in traditional, and folk medicine due to its carminative, stimulant, antiseptic, diuretic, antihypertensive, and hepatoprotective activities. Non-specific lipid transfer proteins (nsLTPs) reported from various plants are known to be involved in transferring lipids between membranes and in plants defense response. Here, we describe the complete primary structure of a monomeric non-specific lipid transfer protein 1 (nsLTP1), with molecular weight of 9.66 kDa, from ajwain seeds. The nsLTP1 has been purified by combination of chromatographic techniques, and further characterized by mass spectrometry, and Edman degradation. The ajwain nsLTP1 …


Seasonal Origins Of Soil Water Used By Trees, Scott T. Allen, James W. Kirchner, Sabine Braun, Rolf T. W. Siegwolf, Gregory R. Goldsmith Mar 2019

Seasonal Origins Of Soil Water Used By Trees, Scott T. Allen, James W. Kirchner, Sabine Braun, Rolf T. W. Siegwolf, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Rain recharges soil water storages and either percolates downward into aquifers and streams or is returned to the atmosphere through evapotranspiration. Although it is commonly assumed that summer rainfall recharges plant-available water during the growing season, the seasonal origins of water used by plants have not been systematically explored. We characterize the seasonal origins of waters in soils and trees by comparing their midsummer isotopic signatures (δ2H) to seasonal isotopic cycles in precipitation, using a new seasonal origin index. Across 182 Swiss forest sites, xylem water isotopic signatures show that summer rain was not the predominant water source …


Acidulant Effect On Greening, Reducing Capacity, And Tryptophan Fluorescence Of Sunflower Butter Cookie Dough During Refrigerated Storage, Joele Tsopkeng Atonfack, Zeynep Akyol Ataman, Lilian M. Were Oct 2018

Acidulant Effect On Greening, Reducing Capacity, And Tryptophan Fluorescence Of Sunflower Butter Cookie Dough During Refrigerated Storage, Joele Tsopkeng Atonfack, Zeynep Akyol Ataman, Lilian M. Were

Food Science Faculty Articles and Research

BACKGROUND: Sunflower seed derived butter can be a source of protein and phenolic antioxidants in refrigerated dough. Chlorogenic quinone-amino acid induced greening can however occur at alkaline pH, which could result in less bioavailable conjugated phenol-amino acids. Acidulants were tested as potential anti-greening ingredients in refrigerated chemically leavened cookie dough. Effect of refrigerated storage time, leavening agents and acidulants on tryptophan fluorescence (»ex=280nm, »em=300-500), color (hunter LAB), reducing capacity (DPPH and Folin-Ciocalteu reagent reducing capacity/FCRC), and hydroxycinnamic acids were measured.

RESULTS: The pH range of acidified doughs was 4.83–6.98 compared to 7.65- 9.18 in nonacidified leavened doughs after 24 days. …


Foliar Water Uptake: Processes, Pathways, And Integration Into Plant Water Budgets, Z. Carter Berry, Nathan C. Emery, Sybil G. Gotsch, Gregory R. Goldsmith Sep 2018

Foliar Water Uptake: Processes, Pathways, And Integration Into Plant Water Budgets, Z. Carter Berry, Nathan C. Emery, Sybil G. Gotsch, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Nearly all plant families, represented across most major biomes, absorb water directly through their leaves. This phenomenon is commonly referred to as foliar water uptake. Recent studies have suggested that foliar water uptake provides a significant water subsidy that can influence both plant water and carbon balance across multiple spatial and temporal scales. Despite this, our mechanistic understanding of when, where, how, and to what end water is absorbed through leaf surfaces remains limited. We first review the evidence for the biophysical conditions necessary for foliar water uptake to occur, focusing on the plant and atmospheric water potentials necessary to …


Effects Of Fruit Position In Standard Place Pack Cartons And Gamma 1 Irradiation On The Postharvest Quality Of ‘Barnfield’ Navel Oranges, Karina Cruz Rodriguez (Friscia), José De Jesús Ornelas-Paz, Vrani Ibarra-Junquera, Maria Criselda Toto, Akanksha Jain, Anuradha Prakash Aug 2018

Effects Of Fruit Position In Standard Place Pack Cartons And Gamma 1 Irradiation On The Postharvest Quality Of ‘Barnfield’ Navel Oranges, Karina Cruz Rodriguez (Friscia), José De Jesús Ornelas-Paz, Vrani Ibarra-Junquera, Maria Criselda Toto, Akanksha Jain, Anuradha Prakash

Food Science Faculty Articles and Research

The objective of this study was to determine if oranges in the top and bottom layers within a Standard Place Pack were impacted differently by irradiation after long-term storage. ‘Barnfield’ Navel oranges were packed in Standard Place Pack cartons and treated with 0, 0.15, or 1 kGy of gamma irradiation. The fruit were stored for 3 weeks at 5 °C and then for 1 week at 20 °C. After storage, the fruit from the top and bottom layers were separately evaluated for quality. The development of stem-end rind breakdown (SERB) was the main cause of quality loss and was greater …


Structural And Defensive Roles Of Angiosperm Leaf Venation Network Reticulation Ecross An Andes-Amazon Elevation Gradient, Benjamin Blonder, Norma Salinas, Lisa Patrick Bentley, Alexander Shenkin, Percy Chambi-Porroa, Yolvi Valdez Tejeira, Tatiana Erika Boza Espinoza, Gregory R. Goldsmith, Lucas Enrico, Roberta Martin, Gregory P. Asner, Sandra Diaz, Brian J. Enquist, Yadvinder Malhi Feb 2018

Structural And Defensive Roles Of Angiosperm Leaf Venation Network Reticulation Ecross An Andes-Amazon Elevation Gradient, Benjamin Blonder, Norma Salinas, Lisa Patrick Bentley, Alexander Shenkin, Percy Chambi-Porroa, Yolvi Valdez Tejeira, Tatiana Erika Boza Espinoza, Gregory R. Goldsmith, Lucas Enrico, Roberta Martin, Gregory P. Asner, Sandra Diaz, Brian J. Enquist, Yadvinder Malhi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

1.The network of minor veins of angiosperm leaves may include loops (reticulation). Variation in network architecture has been hypothesized to have hydraulic and also structural and defensive functions.

2.We measured venation network trait space in eight dimensions for 136 biomass-dominant angiosperm tree species along a 3,300 m elevation gradient in southeastern Peru. We then examined the relative importance of multiple ecological, and evolutionary predictors of reticulation.

3.Variation in minor venation network reticulation was constrained to three axes. These axes described branching vs. reconnecting veins, elongated vs. compact areoles, and high vs. low density veins. Variation in the first two axes …


Lowering Greening Of Cookies Made From Sunflower Butter Using Acidic Ingredients And Effect On Reducing Capacity, Tryptophan And Protein Oxidation, Sihui Liang, Hanh Lan Tran, Lilian Were Jan 2018

Lowering Greening Of Cookies Made From Sunflower Butter Using Acidic Ingredients And Effect On Reducing Capacity, Tryptophan And Protein Oxidation, Sihui Liang, Hanh Lan Tran, Lilian Were

Food Science Faculty Articles and Research

Lowering of greening formed from oxidized chlorogenic acid (CGA) and amino groups, and favoured at alkaline pH, was investigated using acidic ingredients (sour cream, buttermilk, yoghurt, and honey) in sunflower butter cookies. Cookies with maple syrup added were used as a positive control. Changes in greening intensity, greening reactants (total phenols, CGA, protein), antioxidant capacity, tryptophan and Schiff base fluorescence were measured. Percentage greening, pH and aw of cookies followed the same order: maple syrup> sour cream ≥ buttermilk> yoghurt> honey. pH was positively correlated with greening intensity (r=0.77) and negatively correlated with CGA (r=-0.96). Total phenolic content, antioxidant capacity, …


Inferring Foliar Water Uptake Using Stable Isotopes Of Water, Gregory R. Goldsmith, Marco M. Lehmann, Lucas A. Cernusak, Matthias Arend, Rolf T.W. Siegwolf Jul 2017

Inferring Foliar Water Uptake Using Stable Isotopes Of Water, Gregory R. Goldsmith, Marco M. Lehmann, Lucas A. Cernusak, Matthias Arend, Rolf T.W. Siegwolf

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A growing number of studies have described the direct absorption of water into leaves, a phenomenon known as foliar water uptake. The resultant increase in the amount of water in the leaf can be important for plant function. Exposing leaves to isotopically enriched or depleted water sources has become a common method for establishing whether or not a plant is capable of carrying out foliar water uptake. However, a careful inspection of our understanding of the fluxes of water isotopes between leaves and the atmosphere under high humidity conditions shows that there can clearly be isotopic exchange between the two …


Cellular And Molecular Targets Of Menthol Actions, Murat Oz, Eslam El Nebrisi, Keun-Hang Susan Yang, Frank Christopher Howarth, Lina T. Al Kury Jul 2017

Cellular And Molecular Targets Of Menthol Actions, Murat Oz, Eslam El Nebrisi, Keun-Hang Susan Yang, Frank Christopher Howarth, Lina T. Al Kury

Mathematics, Physics, and Computer Science Faculty Articles and Research

Menthol belongs to monoterpene class of a structurally diverse group of phytochemicals found in plant-derived essential oils. Menthol is widely used in pharmaceuticals, confectionary, oral hygiene products, pesticides, cosmetics, and as a flavoring agent. In addition, menthol is known to have antioxidant, anti-inflammatory, and analgesic effects. Recently, there has been renewed awareness in comprehending the biological and pharmacological effects of menthol. TRP channels have been demonstrated to mediate the cooling actions ofmenthol. There has been new evidence demonstrating thatmenthol can significantly influence the functional characteristics of a number of different kinds of ligand and voltage-gated ion channels, indicating that at …


Hydrogenation Of Organic Matter As A Terminal Electron Sink Sustains High Co2:Ch4 Production Ratios During Anaerobic Decomposition, Rachel M. Wilson, Malak M. Tfaily, Virginia I. Rich, Jason K. Keller, Scott D. Bridgham, Cassandra Medvedeff Zalman, Laura Meredith, Paul J. Hanson, Mark Hines, Laurel Pfeifer-Meister, Scott R. Saleska, Patrick Crill, William T. Cooper, Jeff P. Chanton, Joel E. Kostka Jul 2017

Hydrogenation Of Organic Matter As A Terminal Electron Sink Sustains High Co2:Ch4 Production Ratios During Anaerobic Decomposition, Rachel M. Wilson, Malak M. Tfaily, Virginia I. Rich, Jason K. Keller, Scott D. Bridgham, Cassandra Medvedeff Zalman, Laura Meredith, Paul J. Hanson, Mark Hines, Laurel Pfeifer-Meister, Scott R. Saleska, Patrick Crill, William T. Cooper, Jeff P. Chanton, Joel E. Kostka

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Once inorganic electron acceptors are depleted, organic matter in anoxic environments decomposes by hydrolysis, fermentation, and methanogenesis, requiring syntrophic interactions between microorganisms to achieve energetic favorability. In this classic anaerobic food chain, methanogenesis represents the terminal electron accepting (TEA) process, ultimately producing equimolar CO2 and CH4 for each molecule of organic matter degraded. However, CO2:CH4 production in Sphagnum-derived, mineral-poor, cellulosic peat often substantially exceeds this 1:1 ratio, even in the absence of measureable inorganic TEAs. Since the oxidation state of C in both cellulose-derived organic matter and acetate is 0, and CO2 has …


Predicting Trait-Environment Relationships For Venation Networks Elong An Andes-Amazon Elevation Gradient, Benjamin Blonder, Norma Salinas, Lisa Patrick Bentley, Alexander Shenkin, Percy O. Chambi Porroa, Yolvi Valdez Tejeira, Cyrille Violle, Nikolaos M. Fyllas, Gregory R. Goldsmith, Roberta E. Martin, Gregory P. Asner, Sandra Diaz, Brian J. Enquist, Yadvinder Malhi Apr 2017

Predicting Trait-Environment Relationships For Venation Networks Elong An Andes-Amazon Elevation Gradient, Benjamin Blonder, Norma Salinas, Lisa Patrick Bentley, Alexander Shenkin, Percy O. Chambi Porroa, Yolvi Valdez Tejeira, Cyrille Violle, Nikolaos M. Fyllas, Gregory R. Goldsmith, Roberta E. Martin, Gregory P. Asner, Sandra Diaz, Brian J. Enquist, Yadvinder Malhi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding functional trait-environment relationships (TERs) may improve predictions of community assembly. However, many empirical TERs have been weak or lacking conceptual foundation. TERs based on leaf venation networks may better link individuals and communities via hydraulic constraints. We report measurements of vein density, vein radius, and leaf thickness for more than 100 dominant species occurring in ten forest communities spanning a 3,300 m Andes-Amazon elevation gradient in Peru. We use these data to measure the strength of TERs at community scale and to determine whether observed TERs are similar to those predicted by physiological theory. We found strong support for …


Can Functional Traits Predict Plant Community Response To Global Change?, Sarah Kimball, Jennifer L. Funk, Marko J. Spasojevic, Katharine N. Suding, Scot Parker, Michael K. Goulden Dec 2016

Can Functional Traits Predict Plant Community Response To Global Change?, Sarah Kimball, Jennifer L. Funk, Marko J. Spasojevic, Katharine N. Suding, Scot Parker, Michael K. Goulden

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

One primary goal at the intersection of community ecology and global change biology is to identify functional traits that are useful for predicting plant community response to global change. We used observations of community composition from a long-term field experiment in two adjacent plant communities (grassland and coastal sage shrub) to investigate how nine key plant functional traits were related to altered water and nitrogen availability following fire. We asked whether the functional responses of species found in more than one community type were context dependent and whether community-weighted mean and functional diversity were significantly altered by water and nitrogen …


Variation In Leaf Wettability Traits Along A Tropical Montane Elevation Gradient, Gregory R. Goldsmith, Lisa Patrick Bentley, Alexander Shenkin, Norma Salinas, Benjamin Blonder, Roberta E. Martin, Rosa Castro-Ccossco, Percy Chambi-Porroa, Sandra Diaz, Brian J. Enquist, Gregory P. Asner, Yadvinder Malhi Jul 2016

Variation In Leaf Wettability Traits Along A Tropical Montane Elevation Gradient, Gregory R. Goldsmith, Lisa Patrick Bentley, Alexander Shenkin, Norma Salinas, Benjamin Blonder, Roberta E. Martin, Rosa Castro-Ccossco, Percy Chambi-Porroa, Sandra Diaz, Brian J. Enquist, Gregory P. Asner, Yadvinder Malhi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

  • Leaf wetting is often considered to have negative effects on plant function, such that wet environments may select for leaves with certain leaf surface, morphological, and architectural traits that reduce leaf wettability. However, there is growing recognition that leaf wetting can have positive effects.
  • We measured variation in two traits, leaf drip tips and leaf water repellency, in a series of nine tropical forest communities occurring along a 3300-m elevation gradient in southern Peru. To extend this climatic gradient, we also assembled published leaf water repellency values from 17 additional sites. We then tested hypotheses for how these traits should …