Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 27 of 27

Full-Text Articles in Life Sciences

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas E. Clemente, Paul E. Staswick, Harkamal Walia Jan 2020

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas E. Clemente, Paul E. Staswick, Harkamal Walia

Agronomy & Horticulture -- Faculty Publications

Drought stress is the major limiting factor in agriculture. Wheat, which is the most widely grown crop in the world, is predominantly cultivated in drought-prone rainfed environments. Since roots play a critical role in water uptake, root response to water limitations is an important component for enhancing wheat adaptation. In an effort to discover novel genetic sources for improving wheat adaptation, we characterized a wheat translocation line with a chromosomal segment from Agropyron elongatum, a wild relative of wheat, which unlike common wheat maintains root growth under limited-water conditions. By exploring the root transcriptome data, we found that reduced transcript ...


Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones Dec 2019

Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones

Honors Scholar Theses

Vesicular-arbuscular mycorrhizae (VAM) are an ancient mutualism in which soil-dwelling fungi enhance plant absorption of phosphorus and nitrogen in exchange for photosynthates. VAM are sensitive to changes in soil moisture and nutrient content, fluctuating between mutualism and parasitism depending on conditions of drought stress and nutrient deficiency. Understanding how VAM respond to precipitation changes is crucial for both conservation and agricultural purposes. To test how soil moisture changes the effects of VAM colonization and growth in little bluestem (Schizachyrium scoparium), a common prairie grass, I planted 300 seeds in a greenhouse in sterilized soil and soil inoculated with VAM fungi ...


Impact Of Drought On Chemical Composition And Sugar Yields From Dilute-Acid Pretreatment And Enzymatic Hydrolysis Of Miscanthus, A Tall Fescue Mixture, And Switchgrass, Amber Hoover, Rachel Emerson, Allison Ray, Daniel Stevens, Sabrina Morgan, Marnie Cortez, Robert Kallenbach, Matthew Sousek, Rodney Farris, Dayna Daubaras Jan 2018

Impact Of Drought On Chemical Composition And Sugar Yields From Dilute-Acid Pretreatment And Enzymatic Hydrolysis Of Miscanthus, A Tall Fescue Mixture, And Switchgrass, Amber Hoover, Rachel Emerson, Allison Ray, Daniel Stevens, Sabrina Morgan, Marnie Cortez, Robert Kallenbach, Matthew Sousek, Rodney Farris, Dayna Daubaras

Agronomy & Horticulture -- Faculty Publications

Environmental factors like drought impact the quality of biomass entering a bioconversion process. Drought often reduces the sugar content in lignocellulosic biomass, which could have economic impacts, particularly when compounded with losses in dry biomass yield; however, the effects on conversion efficiency are not completely understood. This study investigated how drought may impact biomass composition and sugar yields from dilute-acid pretreatment and enzymatic hydrolysis of Miscanthus, a tall fescue mixture, and switchgrass from Nebraska, Missouri, and Oklahoma, respectively, grown as part of Regional Feedstock Partnership field trials. Samples were grown and harvested in 2010 during non-drought conditions and in 2012 ...


The Impact Of Climate And Elevation On The Growth And Mortality Of Piñon Pine, Alice M. Fretz Jul 2017

The Impact Of Climate And Elevation On The Growth And Mortality Of Piñon Pine, Alice M. Fretz

Biology ETDs

The Southwestern United States is currently experiencing severe drought, resulting in the mortality of many tree species. Piñon-juniper woodlands are an extensive biome in the Southwest, and are highly vulnerable to extended periods of drought that lead to tree mortality. Specifically, Pinus edulis populations are decreasing due to increasingly arid conditions. I used dendrochronology to investigate how tree growth rings of Pinus edulis reflect severe drought in living and dead trees. I also investigated how severe drought affects Pinus edulis along an altitudinal gradient. Tree core samples were taken from currently living and dead trees, as well as from trees ...


Species Composition But Not Diversity Explains Recovery From The 2011 Drought In Texas Grasslands, Xia Xu, H. Wayne Polley, Kirsten S. Hofmockel, Brian J. Wilsey Mar 2017

Species Composition But Not Diversity Explains Recovery From The 2011 Drought In Texas Grasslands, Xia Xu, H. Wayne Polley, Kirsten S. Hofmockel, Brian J. Wilsey

Ecology, Evolution and Organismal Biology Publications

Extreme droughts can have profound direct consequences for grassland ecosystems, but it is poorly known how ecosystems recover from drought and what ecological factors are associated with recovery. Recovery occurs when ecosystem functioning returns to values observed prior to a perturbation. Here, we tested for ecosystem recovery after an extreme drought in 2011 in previously established native and exotic experimental communities in Central Texas. Planted mixtures of all native and all exotic species were crossed with a summer irrigation treatment, with eight community compositions (random draws) per treatment. Prior to the drought, native plots had higher diversity than exotic plots ...


The Role Of Tre6p And Snrk1 In Maize Early Kernel Development And Events Leading To Stress-Induced Kernel Abortion, Samuel W. Bledsoe, Clémence Henry, Cara A. Griffiths, Matthew J. Paul, Regina Feil, John E. Lunn, Mark Stitt, L. Mark Lagrimini Jan 2017

The Role Of Tre6p And Snrk1 In Maize Early Kernel Development And Events Leading To Stress-Induced Kernel Abortion, Samuel W. Bledsoe, Clémence Henry, Cara A. Griffiths, Matthew J. Paul, Regina Feil, John E. Lunn, Mark Stitt, L. Mark Lagrimini

Agronomy & Horticulture -- Faculty Publications

Background: Drought stress during flowering is a major contributor to yield loss in maize. Genetic and biotechnological improvement in yield sustainability requires an understanding of the mechanisms underpinning yield loss. Sucrose starvation has been proposed as the cause for kernel abortion; however, potential targets for genetic improvement have not been identified. Field and greenhouse drought studies with maize are expensive and it can be difficult to reproduce results; therefore, an in vitro kernel culture method is presented as a proxy for drought stress occurring at the time of flowering in maize (3 days after pollination). This method is used to ...


Geospatial Analysis Of Droughts, Rice And Wheat Production, And Agrarian Vulnerability: A District-Level Study Of The Self-Calibrated Palmer Drought Severity Index In India, Aaron Michael Shew May 2016

Geospatial Analysis Of Droughts, Rice And Wheat Production, And Agrarian Vulnerability: A District-Level Study Of The Self-Calibrated Palmer Drought Severity Index In India, Aaron Michael Shew

Theses and Dissertations

Droughts have affected more people than any other natural disaster in the last century, causing billions in economic damages and millions of deaths. As the Sea Surface Temperatures (SST) have heated in the Indian Ocean, drought patterns across South Asia have changed; the Indian monsoon has become more volatile and less predictable. In this study, monthly self-calibrated Palmer Drought Severity Index (sc-PDSI) data for the time period between 1950 and 2009 were interpolated to India’s districts; then the data were analyzed for changes in frequency and severity. The data were further evaluated using Anselin’s Local Moran’s I ...


Rooting Characteristics And Antioxidant Pigment Responses Of Three Hybrid Bermudagrass [Cynodon Dactylon (L.) Pers. × Cynodon Transvaalensis Burtt- Davy] Cultivars Exposed To Drought, Cory Alan Yurisic May 2016

Rooting Characteristics And Antioxidant Pigment Responses Of Three Hybrid Bermudagrass [Cynodon Dactylon (L.) Pers. × Cynodon Transvaalensis Burtt- Davy] Cultivars Exposed To Drought, Cory Alan Yurisic

Masters Theses

With recent changes in global climate, water use and its conservation have become important topics of discussion. Turfgrasses for lawns, parks, and other recreational areas are often perceived negatively due to the need for irrigation. The identification of turfgrasses possessing an improved ability to withstand water deficit is an important goal in science to curb irrigation requirements in the landscape. Newly released cultivars of hybrid bermudagrass (C. dactylon L. x. C. transvaalensis Burtt-Davy) have demonstrated improved tolerance to stresses such as cold, traffic, and water deficit; however, drought resistance mechanisms of these new cultivars have been largely uninvestigated. Drought resistant ...


Managing Drought Stress In California Agricultural Systems, Gregory D. Brittain Jr. Apr 2016

Managing Drought Stress In California Agricultural Systems, Gregory D. Brittain Jr.

Doctoral Documents from Doctor of Plant Health Program

California is currently facing a historic drought, and this has led many farmers in the state to severely cut back on irrigation. Optimal use of water for irrigation requires a comprehensive understanding of how plants respond physiologically to water stress (Chapter 1). By monitoring water requirements in crops and managing irrigation to meet those requirements, growers can significantly reduce water use (Chapter 2). This can be done through improving application efficiency of irrigation technology as well as increasing the water use efficiency of the crops themselves. Deficit irrigation practices can be used to manipulate the physiology of water use in ...


Temporal Dynamics Of Maize Plant Growth, Water Use, And Leaf Water Content Using Automated High Throughput Rgb And Hyperspectral Imaging, Yufeng Ge, Geng Bai, Vincent Stoerger, James C. Schnable Jan 2016

Temporal Dynamics Of Maize Plant Growth, Water Use, And Leaf Water Content Using Automated High Throughput Rgb And Hyperspectral Imaging, Yufeng Ge, Geng Bai, Vincent Stoerger, James C. Schnable

Biological Systems Engineering: Papers and Publications

Automated collection of large scale plant phenotype datasets using high throughput imaging systems has the potential to alleviate current bottlenecks in data-driven plant breeding and crop improvement. In this study, we demonstrate the characterization of temporal dynamics of plant growth and water use, and leaf water content of two maize genotypes under two different water treatments. RGB (Red Green Blue) images are processed to estimate projected plant area, which are correlated with destructively measured plant shoot fresh weight (FW), dry weight (DW) and leaf area. Estimated plant FW and DW, along with pot weights, are used to derive daily plant ...


Impact Of Pre-Anthesis Water Deficit On Yield And Yield Components In Barley (Hordeum Vulgare L.) Plants Grown Under Controlled Conditions, Zakaria I. Al-Ajlouni, Ayed Al-Abdallat, Abdul Latief A. Al-Ghzawi, Jamal Y. Ayad, Jamal M. Abu Elenein, Nisreen A. Al-Quraan, P. Stephen Baenziger Jan 2016

Impact Of Pre-Anthesis Water Deficit On Yield And Yield Components In Barley (Hordeum Vulgare L.) Plants Grown Under Controlled Conditions, Zakaria I. Al-Ajlouni, Ayed Al-Abdallat, Abdul Latief A. Al-Ghzawi, Jamal Y. Ayad, Jamal M. Abu Elenein, Nisreen A. Al-Quraan, P. Stephen Baenziger

Agronomy & Horticulture -- Faculty Publications

Drought at pre-anthesis stages can influence barley growth and results in yield losses. Therefore, it is important to understand how drought at pre-anthesis can affect different traits associated with yield reduction in barley. The objective of this study was to understand the relevance of the genetic background of major flowering time genes in barley plants subjected to pre-anthesis drought and its impact on yield and yield components. A glasshouse experiment using a Randomized Complete Block Design was conducted to investigate the effect of drought and its timing on yield and yield components on eleven barley genotypes, which were selected to ...


When An Invasive Plant Fails To Invade, Stephen L. Young Oct 2015

When An Invasive Plant Fails To Invade, Stephen L. Young

West Central Research and Extension Center, North Platte

In 2012, much of the US Midwest was gripped in one of the most severe droughts on record. While conducting experimental fieldwork at a site in Nebraska during June of that year, I noticed a single musk thistle (Carduus nutans; Figure 1) that appeared to be in the bolt or early flowering stage, which is typical for the species at that time. Here, however, two things were unusual: this plant was less than 1 meter tall (with adequate moisture and light, musk thistle typically grows to heights of 1–2.5 meters before flowering), and was only 3 months old ...


The Linkages Between Photosynthesis, Productivity, Growth And Biomass In Lowland Amazonian Forests, Yadvinder Malhi, Christopher E. Doughty, Gregory R. Goldsmith, Daniel B. Metcalfe, Cécile A.J. Girardin, Toby R. Marthews, Jhon Del Aguila-Pasquel, Luiz E.O.C. Aragão, Alejandro Araujo-Murakami, Paulo Brando, Antonino C.L. Da Costa, Javier E. Silva-Espejo, Filio Farfán Amézquita, David R. Galbraith, Carlos A. Quesada, Wanderley Rocha, Norma Salinas-Revilla, Divino Silvério, Patrick Meir, Oliver L. Phillips Mar 2015

The Linkages Between Photosynthesis, Productivity, Growth And Biomass In Lowland Amazonian Forests, Yadvinder Malhi, Christopher E. Doughty, Gregory R. Goldsmith, Daniel B. Metcalfe, Cécile A.J. Girardin, Toby R. Marthews, Jhon Del Aguila-Pasquel, Luiz E.O.C. Aragão, Alejandro Araujo-Murakami, Paulo Brando, Antonino C.L. Da Costa, Javier E. Silva-Espejo, Filio Farfán Amézquita, David R. Galbraith, Carlos A. Quesada, Wanderley Rocha, Norma Salinas-Revilla, Divino Silvério, Patrick Meir, Oliver L. Phillips

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Amazonian forests spanning gradients in seasonal water deficit and soil fertility. Using the largest data set assembled to date, ten sites in three countries all studied with a standardized methodology, we find that (i) gross primary productivity (GPP) has a simple relationship with seasonal water deficit, but ...


Genetic And Physiologic Analyses Of Soybean Grain Yields In Water Limited Environments, Dawn Gibson Jan 2015

Genetic And Physiologic Analyses Of Soybean Grain Yields In Water Limited Environments, Dawn Gibson

Graduate Theses and Dissertations

Increasing grain yield in soybean is an important breeding goal for plant breeders. While identification of yield QTL can result in identification of genomic regions for increasing yield, these regions are often not consistent across environments due to genetic and environment interactions. Water limitation for crop growth is one such environment in which yield QTL are not consistent. Water limitations during grain fill can be especially devastating to the final yield of a crop. The objective of this study was to identify and then map QTL in three families of recombinant inbred lines (RILs) developed from two plant introductions and ...


Understanding Rice Adaptation To Varying Agro-Ecosystems: Trait Interactions And Quantitative Trait Loci, Shalabh Dixit, Alexandre Grondin, Cheng-Ruei Lee, Amelia Henry, Thomas-Mitchell Olds, Arvind Kumar Jan 2015

Understanding Rice Adaptation To Varying Agro-Ecosystems: Trait Interactions And Quantitative Trait Loci, Shalabh Dixit, Alexandre Grondin, Cheng-Ruei Lee, Amelia Henry, Thomas-Mitchell Olds, Arvind Kumar

Agronomy & Horticulture -- Faculty Publications

Background: Interaction and genetic control for traits influencing the adaptation of the rice crop to varying environments was studied in a mapping population derived from parents (Moroberekan and Swarna) contrasting for drought tolerance, yield potential, lodging resistance, and adaptation to dry direct seeding. A BC2F3-derived mapping population for traits related to these four trait groups was phenotyped to understand the interactions among traits and to map and align QTLs using composite interval mapping (CIM). The study also aimed to identify QTLs for the four trait groups as composite traits using multivariate least square interval mapping (MLSIM ...


The Molecular Mechanisms Of Brassinosteroid-Regulated Drought Stress Response In Arabidopsis Thaliana, Buyun Tang Jan 2015

The Molecular Mechanisms Of Brassinosteroid-Regulated Drought Stress Response In Arabidopsis Thaliana, Buyun Tang

Graduate Theses and Dissertations

Brassinosteroids (BRs) are involved in diverse developmental processes such as cell elongation, vascular differentiation, senescence and stress response. The mechanisms and regulatory networks of BR-regulated plant growth and development have been well described for the past decade with the identification of receptors, kinases and central transcription factors involved in BR signaling. Recent studies revealed BRs also extensively participated in plant response to environmental stresses, although the mechanisms of BR-regulated stress response is largely unknown. Coordination of plant growth and stress response requires integration of multiple signaling output through hormonal crosstalk. Studies of BR signaling pathway and BR-mediated physiological responses indicate ...


Water Availability As The Driving Factor Of Growth And Physiological Function Of Co-Occurring Scrub Species In Central Florida, Tammy Foster Mar 2014

Water Availability As The Driving Factor Of Growth And Physiological Function Of Co-Occurring Scrub Species In Central Florida, Tammy Foster

Graduate Theses and Dissertations

Florida scrub is a xeromorphic upland shrub community dominated by evergreen oaks that resprout after fire, occurring on moderately to excessively well-drained nutrient-poor sand. Scrub is home to several threatened and endangered animal species (e.g., Florida scrub-jay, gopher tortoise, and indigo snake) and rare and endemic plants. Urban development and agriculture has greatly reduced and fragmented scrub habitat, and because of this Florida scrub is considered one of the most endangered ecosystems in the United States. Climate change is a further threat to Florida scrub. Under a warmer and drier climate, scrub species will be exposed to more frequent ...


A Role Of Swi/Snf Complex In Aba-Dependent Drought Responsive Gene Expression In Arabidopsis Thaliana, Soon-Ki Han Jan 2014

A Role Of Swi/Snf Complex In Aba-Dependent Drought Responsive Gene Expression In Arabidopsis Thaliana, Soon-Ki Han

Publicly Accessible Penn Dissertations

The survival of plants as sessile organisms depends on their ability to cope with environmental challenges. Of key importance in this regard is the phytohormone abscisic acid (ABA). ABA not only promotes seed dormancy but also triggers growth arrest in postgermination embryos that encounter water stress. This is accompanied by increased desiccation tolerance. Postgermination ABA responses in Arabidopsis thaliana are mediated in large part by the ABA-induced basic domain/leucine zipper transcription factor ABA INSENSITIVE5 (ABI5). Here, I show that loss of function of the SWI/SNF chromatin remodeling ATPase BRAHMA (BRM) causes ABA hypersensitivity during postgermination growth arrest. ABI5 ...


Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart Birrell, David Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt Jan 2014

Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart Birrell, David Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt

Agronomy & Horticulture -- Faculty Publications

Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus × giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced for ...


Selecting Drought Tolerant Soybean Genotypes Using Qtls Associated With Shoot Ureide And Nitrogen Concentrations, Alejandro Bolton Aug 2013

Selecting Drought Tolerant Soybean Genotypes Using Qtls Associated With Shoot Ureide And Nitrogen Concentrations, Alejandro Bolton

Theses and Dissertations

In soybean, nitrogen fixation is more sensitive to drought than other physiological processes like photosynthesis. The sensitivity of nitrogen fixation to drought has been associated with high shoot concentrations of ureide and nitrogen under well-watered conditions. Previous research by Hwang et al. (2013) detected quantitative trait loci (QTLs) in a KS4895 by Jackson population associated with shoot ureide and nitrogen concentrations. The present research evaluated the use of these QTLs in selecting genotypes with drought tolerant nitrogen fixation. Our objectives were to compare actual versus expected phenotype of recombinant inbreed lines (RILs) selected using molecular markers, and to evaluate the ...


A Comparison Of Brittlebush (Encelia Farinosa) Productivity And Health During Drought And Post Rainfall, Gabi Diciolli, Karre Lawson, Anders Reimer Oct 2012

A Comparison Of Brittlebush (Encelia Farinosa) Productivity And Health During Drought And Post Rainfall, Gabi Diciolli, Karre Lawson, Anders Reimer

Featured Research

Encelia farinosa is well adapted for drought tolerance as its leaves transform color based on water availability. We were puzzled by a question that any desert botanist must consider. How does the photosynthetic efficiency of E. farinosa fluctuate as it transitions from a state of drought to a state of soil saturation within a 72 hour period? In this experiment we looked at the effects of irrigation on the health and quantum yield of the brittlebush by looking at photosynthetic rates using the portable photosynthesis system LI-COR 6400 when applied to two leaves on a given plant and water potential ...


Crop Updates 2011 - Cereals, David Bowran, Bill Crabtree, Peter Carberry, Peter Burges, Bevan Buirchell, Ben Curtis, Sarah Ellis, Brenda Shackley, Christine Zaicou, Siva Sivapalan, Penny Goldsmith, Gae Plunkett, Darshan Sharma, Mario D'Antuono, Art Diggle, Peter Mangano, Sally Peltzer, Michael Renton, Bill Macleod, Fumie Horiuchi, George Wyatt, Geoff Anderson, Richard Bell, Ross Brennan, Wen Chen, Penny Riffkin Feb 2011

Crop Updates 2011 - Cereals, David Bowran, Bill Crabtree, Peter Carberry, Peter Burges, Bevan Buirchell, Ben Curtis, Sarah Ellis, Brenda Shackley, Christine Zaicou, Siva Sivapalan, Penny Goldsmith, Gae Plunkett, Darshan Sharma, Mario D'Antuono, Art Diggle, Peter Mangano, Sally Peltzer, Michael Renton, Bill Macleod, Fumie Horiuchi, George Wyatt, Geoff Anderson, Richard Bell, Ross Brennan, Wen Chen, Penny Riffkin

Crop Updates

This session covers eleven papers from different authors:

OPENING, NEW CROP VARIETIES & DECISION SUPPORT

Opening

1. Overview of the 2010 season, David Bowran, Director, Practice and Systems Innovation, Department of Agriculture and Food,

2. My experience in a drought as a farmer and consultant, Bill Crabtree, Morawa, Western Australia

3. Meeting the productivity and sustainability challenges to Australian agriculture until 2030, Peter Carberry, CSIRO Sustainable Agriculture Flagship

New Crop Varieties

4. National Variety Trials (NTV) wheat variety performance – captivity vs broadacre, Peter Burgess, Kalyx Agriculture

5. WALAN2289 – a new lupin variety to replace Mandelup in the system, Bevan Buirchell, Department ...


The Future Of Southern Agriculture, Gregory Keith Bartley Jr. Feb 2010

The Future Of Southern Agriculture, Gregory Keith Bartley Jr.

Gregory Keith Bartley Jr.

The increasing demand for the supply of energy in the south heavily impacts the allocation of water for use in agriculture. With such a high percentage of the south's freshwater going towards energy production, little can make its way into food, feed, and fiber. Because the need for this exponential energy production in the south is currently greater than its agricultural importance, southern farmers are left to endure heavy irrigation restrictions. The solution to this problem can manifest itself in one of two ways. Southern states can either implement strategies that can reduce plant water consumption without reducing yield ...


Maestra2: A Model For Simulating Spatially Explicit Carbon Dioxide Exchange Rates Among Species' Water Stress Response, Robert Reynolds Dec 2007

Maestra2: A Model For Simulating Spatially Explicit Carbon Dioxide Exchange Rates Among Species' Water Stress Response, Robert Reynolds

All Theses

MAESTRA2, a species specific mechanistic model, was parameterized to estimate water use, carbon accumulation and organ specific respiration of five deciduous tree species under both irrigated and water stressed conditions. The model was validated using temporally and spatially explicit ecophysiological data to account for seasonal changes in species physiology. The following tree species: Acer rubrum L. 'Summer Red' (A. rubrum), Betula nigra (B. nigra), Paulownia elongata (P. elongata), Quercus nuttallii (Q. nuttallii), and Quercus phellos (Q. phellos) were intensively measured and organ specific destructively harvested samples were compared to modeled estimates of carbon accumulation. Among species, we observed variability in ...


Crop Updates 2005 - Cereals, Darsham Sharma, Brenda Shackley, Mohammad Amjad, Christine M. Zaicou-Kunesch, Wal Anderson, D. Tennant, Steve Penny Jr, Ben Curtis, Veronika Reck, Richard Richards, Gavin Knell, Steve Curtin, David Sermon, Alan Bedggood, T. B. Biddulph, T. L. Setter, J. A. Plummer, D. J. Mares, H. Khabaz-Saberi, I. Waters, G. Mcdonald, Harmohinder Dhammu, David Nicholson, Chris Roberts, Stephen Loss, Ross Brennan, Kith Jayasena, Eddy Pol, Simon Teakle, R. Loughman, C. Beard, B. Paynter, K. Tanaka, G. Poulish, A. Smith, Paul Damon, Zed Rengel, Lionel Martin, Narelle Hill, Ron Mctaggart, Ray Tugwell, Geoff Thomas, Manisha Shankar, John Majewski, D. Foster, H. Golzar, J. Piotrowski, Rob Grima, Jeff Russell, Angie Roe, Vivien A. Vanstone, Sean J. Kelly, Helen F. Hunter, Mena C. Gilchrist, C. R. Newman, Svetlana Micic, Phil Michael, Gabrielle Coupland, Ern Kostas, Mohammed Hamza, Tina Botwright Acuña, Len Wade, Ingrid Richardson Feb 2005

Crop Updates 2005 - Cereals, Darsham Sharma, Brenda Shackley, Mohammad Amjad, Christine M. Zaicou-Kunesch, Wal Anderson, D. Tennant, Steve Penny Jr, Ben Curtis, Veronika Reck, Richard Richards, Gavin Knell, Steve Curtin, David Sermon, Alan Bedggood, T. B. Biddulph, T. L. Setter, J. A. Plummer, D. J. Mares, H. Khabaz-Saberi, I. Waters, G. Mcdonald, Harmohinder Dhammu, David Nicholson, Chris Roberts, Stephen Loss, Ross Brennan, Kith Jayasena, Eddy Pol, Simon Teakle, R. Loughman, C. Beard, B. Paynter, K. Tanaka, G. Poulish, A. Smith, Paul Damon, Zed Rengel, Lionel Martin, Narelle Hill, Ron Mctaggart, Ray Tugwell, Geoff Thomas, Manisha Shankar, John Majewski, D. Foster, H. Golzar, J. Piotrowski, Rob Grima, Jeff Russell, Angie Roe, Vivien A. Vanstone, Sean J. Kelly, Helen F. Hunter, Mena C. Gilchrist, C. R. Newman, Svetlana Micic, Phil Michael, Gabrielle Coupland, Ern Kostas, Mohammed Hamza, Tina Botwright Acuña, Len Wade, Ingrid Richardson

Crop Updates

This session covers thirty six papers from different authors:

WHEAT AGRONOMY

1. Optimum sowing time of new wheat varieties in Western Australia, Darshan Sharma, Brenda Shackley, Mohammad Amjad, Christine M. Zaicou-Kunesch and Wal Anderson, Department of Agriculture

2. Wheat varieties updated in ‘Flowering Calculator’: A model predicting flowering time, B. Shackley, D. Tennant, D. Sharma and C.M. Zaicou-Kunesch, Department of Agriculture

3. Plant populations for wheat varieties, Christine M. Zaicou-Kunesch, Wal Anderson, Darshan Sharma, Brenda Shackley and Mohammad Amjad, Department of Agriculture

4. New wheat cultivars response to fertiliser nitrogen in four major agricultural regions of Western Australia, Mohammad ...


Variation In Isoprene Emission From Quercus Rubra: Sources, Causes, And Consequences For Estimating Fluxes, Jennifer L. Funk, Clive G. Jones, Dennis W. Gray, Heather L. Throop, Laura A. Hyatt, Manuel T. Lerdau Jan 2005

Variation In Isoprene Emission From Quercus Rubra: Sources, Causes, And Consequences For Estimating Fluxes, Jennifer L. Funk, Clive G. Jones, Dennis W. Gray, Heather L. Throop, Laura A. Hyatt, Manuel T. Lerdau

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Isoprene is the dominant volatile organic compound produced in many forest systems. Uncertainty in estimates of leaf level isoprene emission rate stems from an insufficient understanding of the patterns and processes controlling isoprene emission capacity in plant leaves. Previous studies suggest that variation in isoprene emission capacity is substantial; however, it is not known at what scale emission capacity is the most variable. Identifying the sources of variation in emission capacity has implications for conducting measurements and for model development, which will ultimately improve emission estimates and models of tropospheric chemistry. In addition, understanding the sources of variation will help ...


Leaf Diffusive Resistance And Relative Water Content As Indications Of Varietal Sensitivity To Drought In Potatoes, Darlene A. Wilcox, Richard A. Ashley Jun 1980

Leaf Diffusive Resistance And Relative Water Content As Indications Of Varietal Sensitivity To Drought In Potatoes, Darlene A. Wilcox, Richard A. Ashley

Storrs Agricultural Experiment Station

No abstract provided.