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2010

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Articles 4921 - 4950 of 5146

Full-Text Articles in Life Sciences

Genome Sequence Of The Palaeopolyploid Soybean, Jeremy Schmutz, Steven B. Cannon, Jessica Schlueter, Jianxin Ma, Therese Mitros, William Nelson, David L. Hyten, Qijian Song, Jay J. Thelen, Jianlin Cheng, Dong Xu, Uffe Hellsten, Gregory D. May, Yeisoo Yu, Tetsuya Sakurai, Taishi Umezawa, Madan K. Bhattacharyya, Devinder Sandhu, Babu Valliyodan, Erika Lindquist, Myron Peto, David Grant, Shengqiang Shu, David Goodstein, Kerrie Barry, Montona Futrell-Griggs, Brian Abernathy, Jianchang Du, Zhixi Tian, Liucun Zhu, Navdeep Gill, Trupti Joshi, Marc Libault, Ananad Sethuraman, Xue-Cheng Zhang, Kazuo Shinozaki, Henry T. Nguyen, Rod A. Wing, Perry Cregan, James E. Specht, Jane Grimwood, Dan Rokhsar, Gary Stacey, Randy C. Shoemaker, Scott A. Jackson Jan 2010

Genome Sequence Of The Palaeopolyploid Soybean, Jeremy Schmutz, Steven B. Cannon, Jessica Schlueter, Jianxin Ma, Therese Mitros, William Nelson, David L. Hyten, Qijian Song, Jay J. Thelen, Jianlin Cheng, Dong Xu, Uffe Hellsten, Gregory D. May, Yeisoo Yu, Tetsuya Sakurai, Taishi Umezawa, Madan K. Bhattacharyya, Devinder Sandhu, Babu Valliyodan, Erika Lindquist, Myron Peto, David Grant, Shengqiang Shu, David Goodstein, Kerrie Barry, Montona Futrell-Griggs, Brian Abernathy, Jianchang Du, Zhixi Tian, Liucun Zhu, Navdeep Gill, Trupti Joshi, Marc Libault, Ananad Sethuraman, Xue-Cheng Zhang, Kazuo Shinozaki, Henry T. Nguyen, Rod A. Wing, Perry Cregan, James E. Specht, Jane Grimwood, Dan Rokhsar, Gary Stacey, Randy C. Shoemaker, Scott A. Jackson

Department of Agronomy and Horticulture: Faculty Publications

Soybean (Glycine max) is one of the most important crop plants for seed protein and oil content, and for its capacity to fix atmospheric nitrogen through symbioses with soil-borne microorganisms. We sequenced the 1.1-gigabase genome by a whole-genome shotgun approach and integrated it with physical and high-density genetic maps to create a chromosome-scale draft sequence assembly. We predict 46,430 protein-coding genes, 70% more than Arabidopsis and similar to the poplar genome which, like soybean, is an ancient polyploid (palaeopolyploid). About 78% of the predicted genes occur in chromosome ends, which comprise less than one-half of the genome but …


‘Food For Life’: Looking Beyond The Horizon, Charles A. Francis, John W. Doran Jan 2010

‘Food For Life’: Looking Beyond The Horizon, Charles A. Francis, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Our real challenge appears to be anticipating what the major challenges and constraints will be to food production and distribution a decade or more into the future. This could be called ‘Beyond the Horizon’ thinking. Today there is little disagreement over the massive depletion on a global scale of two essential inputs to agriculture: fossil fuels and fresh water. We also recognize that phosphorus is found in concentrated form in only a few deposits in nature, and that agriculture is rapidly using this limited resource and dispersing it through harvested products and soil loss from fields in forms that make …


Dryland Performance Of Sweet Sorghum And Grain Crops For Biofuel In Nebraska, Charles S. Wortmann, Adam Liska, Richard B. Ferguson, Drew J. Lyon, R. N. Klein, Ismail M. Dweikat Jan 2010

Dryland Performance Of Sweet Sorghum And Grain Crops For Biofuel In Nebraska, Charles S. Wortmann, Adam Liska, Richard B. Ferguson, Drew J. Lyon, R. N. Klein, Ismail M. Dweikat

Department of Agronomy and Horticulture: Faculty Publications

Sweet sorghum [SS; Sorghum bicolor (L.) Moench] is a potential biofuel crop for the Great Plains. Sweet sorghum was compared with corn [Zea mays (L.)] and grain sorghum for potential ethanol yield, energy use effi ciency, and greenhouse gas (GHG) emissions at seven dryland site-years in Nebraska. Seasonal rainfall ranged from approximately 340 to 660 mm. Soils were deep with medium texture at all site-years. Th e eff ects of seeding rate, N rate, and cultivar on SS performance were evaluated. Sweet sorghum sugar yield was not aff ected by seeding rate and N application at six of seven …


Emissions Savings In The Corn-Ethanol Life Cycle From Feeding Coproducts To Livestock, Virgil R. Bremer, Adam Liska, Terry J. Klopfenstein, Galen E. Erickson, Haishun Yang, Daniel T. Walters, Kenneth G. Cassman Jan 2010

Emissions Savings In The Corn-Ethanol Life Cycle From Feeding Coproducts To Livestock, Virgil R. Bremer, Adam Liska, Terry J. Klopfenstein, Galen E. Erickson, Haishun Yang, Daniel T. Walters, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Environmental regulations on greenhouse gas (GHG) emissions from corn (Zea mays L.)-ethanol production require accurate assessment methods to determine emissions savings from coproducts that are fed to livestock. We investigated current use of coproducts in livestock diets and estimated the magnitude and variability in the GHG emissions credit for coproducts in the corn-ethanol life cycle. The coproduct GHG emissions credit varied by more than twofold, from 11.5 to 28.3 g CO2e per MJ of ethanol produced, depending on the fraction of coproducts used without drying, the proportion of coproduct used to feed beef cattle (Bos taurus …


Effect Of Nitrogen Addition And Weed Interference On Soil Nitrogen And Corn Nitrogen Nutrition, John L. Lindquist, Sean P. Evans, Charles A. Shapiro, Stevan Z. Knezevic Jan 2010

Effect Of Nitrogen Addition And Weed Interference On Soil Nitrogen And Corn Nitrogen Nutrition, John L. Lindquist, Sean P. Evans, Charles A. Shapiro, Stevan Z. Knezevic

Department of Agronomy and Horticulture: Faculty Publications

Weeds cause crop loss indirectly by reducing the quantity of resources available for growth. Quantifying the effects of weed interference on nitrogen (N) supply, crop growth, and N nutrition may assist in making both N and weed management decisions. Experiments were conducted to quantify the effect of N addition and weed interference on soil nitrate-N (NO3- N) over time and the dependence of corn growth on NO3-N availability, determine the corn N nutrition index (NNI) at anthesis, and evaluate if relative chlorophyll content can be utilized as a reliable predictor of NNI. Urea was applied at 0, 60, …


High-Throughput Snp Discovery Through Deep Resequencing Of A Reduced Representation Library To Anchor And Orient Scaffolds In The Soybean Whole Genome Sequence, David L. Hyten, Steven B Cannon, Qijian Song, Nathan Weeks, Edward W Fickus, Randy C Shoemaker, James E. Specht, Andrew Farmer, Gregory D May, Perry B Cregan Jan 2010

High-Throughput Snp Discovery Through Deep Resequencing Of A Reduced Representation Library To Anchor And Orient Scaffolds In The Soybean Whole Genome Sequence, David L. Hyten, Steven B Cannon, Qijian Song, Nathan Weeks, Edward W Fickus, Randy C Shoemaker, James E. Specht, Andrew Farmer, Gregory D May, Perry B Cregan

Department of Agronomy and Horticulture: Faculty Publications

Background: The Soybean Consensus Map 4.0 facilitated the anchoring of 95.6% of the soybean whole genome sequence developed by the Joint Genome Institute, Department of Energy, but its marker density was only sufficient to properly orient 66% of the sequence scaffolds. The discovery and genetic mapping of more single nucleotide polymorphism (SNP) markers were needed to anchor and orient the remaining genome sequence. To that end, next generation sequencing and high-throughput genotyping were combined to obtain a much higher resolution genetic map that could be used to anchor and orient most of the remaining sequence and to help validate the …


Complementary Genetic And Genomic Approaches Help Characterize The Linkage Group I Seed Protein Qtl In Soybean, Yung-Tsi Bolon, Bindu Joseph, Steven B Cannon, Michelle A Graham, Brian W. Diers, Andrew Farmer, Gregory D May, Gary J. Muehlbauer, James Specht, Zheng Jin Tu, Nathan Weeks, Wayne W Xu, Randy C. Shoemaker, Carroll P Vance Jan 2010

Complementary Genetic And Genomic Approaches Help Characterize The Linkage Group I Seed Protein Qtl In Soybean, Yung-Tsi Bolon, Bindu Joseph, Steven B Cannon, Michelle A Graham, Brian W. Diers, Andrew Farmer, Gregory D May, Gary J. Muehlbauer, James Specht, Zheng Jin Tu, Nathan Weeks, Wayne W Xu, Randy C. Shoemaker, Carroll P Vance

Department of Agronomy and Horticulture: Faculty Publications

Background: The nutritional and economic value of many crops is effectively a function of seed protein and oil content. Insight into the genetic and molecular control mechanisms involved in the deposition of these constituents in the developing seed is needed to guide crop improvement. A quantitative trait locus (QTL) on Linkage Group I (LG I) of soybean (Glycine max (L.) Merrill) has a striking effect on seed protein content.

Results: A soybean near-isogenic line (NIL) pair contrasting in seed protein and differing in an introgressed genomic segment containing the LG I protein QTL was used as a resource to demarcate …


Abundance Of Ssr Motifs And Development Of Candidate Polymorphic Ssr Markers (Barcsoyssr_1.0) In Soybean, Qijian Song, Gaofeng Jia, Youlin Zhu, David Grant, Rex T. Nelson, Eun-Young Hwang, D. L. Hyten, P. B. Cregan Jan 2010

Abundance Of Ssr Motifs And Development Of Candidate Polymorphic Ssr Markers (Barcsoyssr_1.0) In Soybean, Qijian Song, Gaofeng Jia, Youlin Zhu, David Grant, Rex T. Nelson, Eun-Young Hwang, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Simple sequence repeat (SSR) genetic markers, also referred to as microsatellites, function in map-based cloning and for marker-assisted selection in plant breeding. The objectives of this study were to determine the abundance of SSRs in the soybean genome and to develop and test soybean SSR markers to create a database of locus-specific markers with a high likelihood of polymorphism. A total of 210,990 SSRs with di-, tri-, and tetranucleotide repeats of five or more were identified in the soybean whole genome sequence (WGS) which included 61,458 SSRs consisting of repeat units of di- (≥10), tri- (≥8), and tetranucleotide (≥7). Among …


Inoculation With Arbuscular Mycorrhizal Fungi Or Crop Rotation With Mycorrhizal Plants Improves The Growth Of Maize In Limed Acid Sulfate Soil, Hasao Higo, Katsunori Isobe, Dong-Jin Kang, Kazuhiro Ujie, Rhae A. Drijber, Ryuichi Ishii Jan 2010

Inoculation With Arbuscular Mycorrhizal Fungi Or Crop Rotation With Mycorrhizal Plants Improves The Growth Of Maize In Limed Acid Sulfate Soil, Hasao Higo, Katsunori Isobe, Dong-Jin Kang, Kazuhiro Ujie, Rhae A. Drijber, Ryuichi Ishii

Department of Agronomy and Horticulture: Faculty Publications

Arbuscular mycorrhizal fungi (AMF) improve the uptake of immobile mineral nutrients such as phosphate, thereby improving plant growth. In acid sulfate soil (ASS), AMF spore density is generally low which impacts root colonization and phosphate uptake. Thus, inoculation may help increase AMF colonization of crops grown in ASS. AMF spore density decreases after cultivation of a non-host crop or bare fallow. In addition, preceding crops affect the growth and yield of subsequent crops. The production of AMF inocula requires AMF-compatible plants. The objective of the present study is to elucidate the effect of preceding crops on the persistence of inoculated …


Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan Holly, Scott Wood, Gin Mccollum Jan 2010

Phase-Linking And The Perceived Motion During Off-Vertical Axis Rotation, Jan Holly, Scott Wood, Gin Mccollum

Mathematics and Statistics Faculty Publications and Presentations

Human off-vertical axis rotation (OVAR) in the dark typically produces perceived motion about a cone, the amplitude of which changes as a function of frequency. This perception is commonly attributed to the fact that both the OVAR and the conical motion have a gravity vector that rotates about the subject. Little-known, however, is that this rotating-gravity explanation for perceived conical motion is inconsistent with basic observations about self-motion perception: (a) that the perceived vertical moves toward alignment with the gravito-inertial acceleration (GIA) and (b) that perceived translation arises from perceived linear acceleration, as derived from the portion of the GIA …


Spring Seed Guide 2010: Nebraska Variety And Hybrid Tests -- Soybeans, Teshome Regassa, Robert N. Klein, Bruce Anderson, Charles A. Shapiro, Jim Krall Jan 2010

Spring Seed Guide 2010: Nebraska Variety And Hybrid Tests -- Soybeans, Teshome Regassa, Robert N. Klein, Bruce Anderson, Charles A. Shapiro, Jim Krall

Department of Agronomy and Horticulture: Faculty Publications

NEBRASKA SOYBEAN VARIETY TESTS 2009

Crop Production Summary: The November 2009 estimated soybean yield for Nebraska was 52 bushels per acre from 4.800 million harvested acres. The total production of soybeans for the state was forecasted at 247 million bushels. These estimates are from the November National Agricultural Statistics Service.


Selecting Strawberry Cultivars For Winter Greenhouse Production, Ellen T. Paparozzi, Stacy A. Adams, George E. Meyer, M. Elizabeth Conley, Vicki L. Schlegel, Erin E. Blankenship, Paul E. Read Jan 2010

Selecting Strawberry Cultivars For Winter Greenhouse Production, Ellen T. Paparozzi, Stacy A. Adams, George E. Meyer, M. Elizabeth Conley, Vicki L. Schlegel, Erin E. Blankenship, Paul E. Read

Department of Agronomy and Horticulture: Faculty Publications

Costs of transportation and food safety concerns have spawned an increase in public support of locally grown vegetables and fruit. With this in mind, a two-phase investigation was planned with the goal of combining low start up costs for sustainable greenhouse production with selection of strawberry cultivars that would provide the greatest number and largest size of berries. Additionally, berries from each cultivar will be analyzed for their beneficial nutraceutical properties to determine if there is a difference among cultivars.


Spring Grazing Impacts On The Vegetation Of Reed Canarygrass–Invaded Wetlands, Heidi Hilhouse, Susan J. Tunnell, James L. Stubbendieck Jan 2010

Spring Grazing Impacts On The Vegetation Of Reed Canarygrass–Invaded Wetlands, Heidi Hilhouse, Susan J. Tunnell, James L. Stubbendieck

Department of Agronomy and Horticulture: Faculty Publications

The Rainwater Basin region in Nebraska is critically important stopover habitat for spring waterfowl migrations, but the ability of these sites to produce sufficient food for migrating waterfowl is endangered by the invasion of reed canarygrass (Phalaris arundinacea L.). This species produces thick litter layers and abundant aboveground biomass, reducing germination and seedling survival of the annual plant species responsible for much of the seed production in the area. Cattle grazing often is used as a management tool in the Rainwater Basin to slow or reverse reed canarygrass invasion and to improve growing conditions for more desirable plant species. …


Rna-Seq Atlas Of Glycine Max: A Guide To The Soybean Transcriptome, Andrew J. Severin, Jenna L. Woody, Yung-Tsi Bolon, Bindu Joseph, Brian W. Diers, Andrew Farmer, Gary J. Muehlbauer, Rex T. Nelson, David Grant, James E. Specht, Michelle A. Graham, Steven B. Cannon, Gregory D. May, Carroll P. Vance, Randy C. Shoemaker Jan 2010

Rna-Seq Atlas Of Glycine Max: A Guide To The Soybean Transcriptome, Andrew J. Severin, Jenna L. Woody, Yung-Tsi Bolon, Bindu Joseph, Brian W. Diers, Andrew Farmer, Gary J. Muehlbauer, Rex T. Nelson, David Grant, James E. Specht, Michelle A. Graham, Steven B. Cannon, Gregory D. May, Carroll P. Vance, Randy C. Shoemaker

Department of Agronomy and Horticulture: Faculty Publications

Background: Next generation sequencing is transforming our understanding of transcriptomes. It can determine the expression level of transcripts with a dynamic range of over six orders of magnitude from multiple tissues, developmental stages or conditions. Patterns of gene expression provide insight into functions of genes with unknown annotation.

Results: The RNA Seq-Atlas presented here provides a record of high-resolution gene expression in a set of fourteen diverse tissues. Hierarchical clustering of transcriptional profiles for these tissues suggests three clades with similar profiles: aerial, underground and seed tissues. We also investigate the relationship between gene structure and gene expression and find …


Efficient Methods Of Estimating Switchgrass Biomass Supplies, Marty R. Schmer, Robert B. Mitchell, Kenneth P. Vogel, Walter H. Schacht, David B. Marx Jan 2010

Efficient Methods Of Estimating Switchgrass Biomass Supplies, Marty R. Schmer, Robert B. Mitchell, Kenneth P. Vogel, Walter H. Schacht, David B. Marx

Department of Agronomy and Horticulture: Faculty Publications

Switchgrass (Panicum virgatum L.) is being developed as a biofuel feedstock for the United States. Efficient and accurate methods to estimate switchgrass biomass feedstock supply within a production area will be required by biorefineries. Our main objective was to determine the effectiveness of indirect methods for estimating biomass yields and composition of switchgrass fields. Indirect measurements were conducted in eastern Nebraska from 2003 to 2007 in which switchgrass biomass yields were manipulated using three nitrogen rates (0 kg N ha-1, 60 kg N ha-1, and 120 kg N ha-1) and two harvest periods …


Fertilizer Rate Effects On Forage Yield Stability And Nutrient Uptake Of Midland Bermudagrass, John A. Guretzky, Maru K. Kering, Jagadeesh Mosali, Eddie Funderburg, Jon T. Biermacher Jan 2010

Fertilizer Rate Effects On Forage Yield Stability And Nutrient Uptake Of Midland Bermudagrass, John A. Guretzky, Maru K. Kering, Jagadeesh Mosali, Eddie Funderburg, Jon T. Biermacher

Department of Agronomy and Horticulture: Faculty Publications

Our objectives were to document effects of nitrogen (N), phosphorus (P), and potassium (K) fertilizer rates on forage yields and uptake of N, P, and K by Midland bermudagrass [Cynodon dactylon (L.) Pers.] on a Minco fine, sandy loam in southern Oklahoma. After six years of this long-term experiment, forage yield responses to fertilization were mixed and depended on year. Stability analysis indicated forage yields responded positively to N fertilization during favorable weather conditions but negatively during poor weather conditions. Application of 112 kg N ha−1 provided the best yield stability and mean annual forage yield among treatments, …


Economic Potential Of Substituting Legumes For Synthetic Nitrogen In Warm Season Perennial Grasses Used For Stocker Cattle Grazing, Maru Kering, John Biermacher, Ryan Reuter, Twain Butler, Job D. Springer, James Rogers, John Blanton, Joe Bouton, John A. Guretzky Jan 2010

Economic Potential Of Substituting Legumes For Synthetic Nitrogen In Warm Season Perennial Grasses Used For Stocker Cattle Grazing, Maru Kering, John Biermacher, Ryan Reuter, Twain Butler, Job D. Springer, James Rogers, John Blanton, Joe Bouton, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

Stocker cattle grazing warm season perennial grasses is an important economic activity in the southern Great Plains. Substantial increases in the price of nitrogen fertilizer is negatively affecting forage producers‟ profitability. Two alternative nitrogen management systems that use annual and perennial legumes have been developed for bermudagrass pastures. The goal of the study is to determine if the legumes systems are more profitable than the conventional practice of applying synthetic sources of nitrogen. Results of the two-year grazing study show that the legume systems could not compete economically with the common practice.


Evaluation Of The Intercom Model For Predicting Growth Of Forest Herbs, Zorica S. Popović, J. L. Lindquist Jan 2010

Evaluation Of The Intercom Model For Predicting Growth Of Forest Herbs, Zorica S. Popović, J. L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

The ecophysiological model INTERCOM was evaluated for its suitability in predicting the growth of perennial forest herbs. A field experiment was conducted to obtain data on photosynthesis and growth parameters of two spring flowering understorey geophytes. Results were used to parameterize the model and its performance was evaluated using the average normalized difference (AE) between predicted and observed biomass and the leaf area index. The model was assumed to provide accurate simulations if the AE was smaller than 0.4. Adjusting the photosynthetic intensity parameters in the model to reflect observed changes in photosynthesis throughout the growing period resulted in the …


Growth And Fitness Components Of Wild × Cultivated Sorghum Bicolor (Poaceae) Hybrids In Nebraska, Lilyrani Sahoo, Jared J. Schmidt, Jeffrey F. Pedersen, Donald Lee, John L. Lindquist Jan 2010

Growth And Fitness Components Of Wild × Cultivated Sorghum Bicolor (Poaceae) Hybrids In Nebraska, Lilyrani Sahoo, Jared J. Schmidt, Jeffrey F. Pedersen, Donald Lee, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

• Premise of the study: Gene flow from crops to wild relatives has received considerable attention since the advent of genetically modified crops. Numerous researchers have found wild – crop hybrids to be nearly as fit as their wild parents, which suggests that crop genes may persist in wild populations. Components of the ecological fitness of cultivated sorghum, its wild relative, shattercane, and their hybrids have not been studied.

• Methods: To assess the potential for gene introgression into shattercane, we crossed cultivated sorghum to a single inbred shattercane line to produce F1 hybrids and measured growth …


Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis Jan 2010

Increased Weed Diversity, Density And Above-Ground Biomass In Long-Term Organic Crop Rotations, Samuel E. Wortman, John L. Lindquist, Milton J. Haar, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

While weed management is consistently a top priority among farmers, there is also growing concern for the conservation of biodiversity. Maintaining diverse weed communities below bioeconomic thresholds may provide ecosystem services for the crop and the surrounding ecosystem. This study was conducted to determine if weed diversity, density and biomass differ within and among organic and conventional crop rotations. In 2007 and 2008, we sampled weed communities in four long-term crop rotations near Mead, Nebraska, United States using seedbank analyses (elutriation and greenhouse emergence) and above-ground biomass sampling. Two conventional crop rotations consisted of a corn (Zea mays) …


Spiny Amaranth Control And Aminopyralid Persistence In Kentucky Pastures, Meghan Elizabeth Edwards Jan 2010

Spiny Amaranth Control And Aminopyralid Persistence In Kentucky Pastures, Meghan Elizabeth Edwards

University of Kentucky Master's Theses

Spiny amaranth is a problematic weed of heavily grazed pastures in Kentucky and surrounding states. The first objective was to evaluate spiny amaranth control when herbicides are applied before and after emergence. Spiny amaranth seed collected in 2008 were seeded in rows in the fall (November) and the following spring (March) in fields located near Lexington and Princeton, KY. Treatments consisted of five application dates and five herbicides plus an untreated control arranged in a split-split plot design. The following parameters were measured: fresh weight, plant height and percent visual control. At both locations pendimethalin applied in November, March and …


Field Scale Bromide Tranport As A Function Of Precipitation Amount, Intensity And Application Time Delay, Vicente Vasquez Jan 2010

Field Scale Bromide Tranport As A Function Of Precipitation Amount, Intensity And Application Time Delay, Vicente Vasquez

University of Kentucky Master's Theses

Rapid and deep transport of solutes in soils can potentially pollute groundwater resources. Field estimates of solute leaching depth based on randomized sampling provide extremely variable field average estimates that confound the treatment effects of the leaching study with the high spatial variation of soil hydraulic properties. The purpose of this study was to investigate the spatial scale of variation of solute (Bromide) leaching depth, and apply this scale of variation to study the leaching depth of Bromide as a function of a sinusoidal application of transport causing factors, i.e., rainfall amount, intensity and application time delay. Solute leaching depth …


Cover Crops And Tillage Systems For Organic Corn Production In Kentucky, Alfonso Suarez Jan 2010

Cover Crops And Tillage Systems For Organic Corn Production In Kentucky, Alfonso Suarez

University of Kentucky Master's Theses

Organic corn (Zea mays L.) producers generally use intensive tillage for weed control. No-till methods reduce soil erosion, conserve water, maintain soil structure and reduce CO2 emissions. The objective of this study was test different cover crops, tillage systems, N sources and N rates for organic corn production. Two tillage systems (no-till and moldboard plow), two cover crops [hairy vetch (Vicia villosa) and rye (Secale cereale)] and two organic N sources [Louisville Green (LG) and Nature Safe (NF)] at four N rates (45, 90, 135, 180 kg N ha-1) were evaluated …


Biodiversity Assessment Of The Fishes Of Saba Bank Atoll, Netherlands Antilles, Jeffrey T. Williams, Kent E. Carpenter, James L. Van Tassell, Paul Hoetjes, Wes Toller, Peter Etnoyer, Michael Smith Jan 2010

Biodiversity Assessment Of The Fishes Of Saba Bank Atoll, Netherlands Antilles, Jeffrey T. Williams, Kent E. Carpenter, James L. Van Tassell, Paul Hoetjes, Wes Toller, Peter Etnoyer, Michael Smith

Biological Sciences Faculty Publications

Biodiversity surveys were conducted on Saba Bank, Netherlands Antilles, to assess ichthyofaunal richness and to compare with published surveys of other Caribbean localities. The primary objective was to estimate the total species richness of the Saba Bank ichthyofauna. A variety of sampling techniques was utilized to survey the fish species of both the visually accessible megafauna and the camouflaged and small-sized species comprising the cryptic ichthyofauna. Based on results presented herein, the number of species known on Saba Bank is increased from 42 previously known species to 270 species. Expected species-accumulation curves demonstrate that the current estimate of species richness …


Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan Jan 2010

Morphological Differences Among Eyeless Amphipods In The Genus Stygobromus Dwelling In Different Subterranean Habitats, David C. Culver, John R. Holsinger, Mary C. Christman, Tanja Pipan

Biological Sciences Faculty Publications

The amphipod genus Stygobromus occurs in a variety of subterranean habitats in North America, including caves, phreatic (groundwater) lakes, and superficial subterranean habitats (seeps and epikarst). The habitats share the absence of light but differ in other features, such as pore size of the habitat, available food, and degree of seasonality. Measurements of body size, antennal size, and antennal segment number of type specimens were compared for 56 species occurring in the eastern United States. Except for differences in body size, differences among species in the four different habitats were not significant. Body size was related to relative pore size …


Conservation Status And Habitat Use Of The West Virginia Spring Salamander (Gyrinophilus Subterraneus) And Spring Salamander (G. Porphyriticus) In General Davis Cave, Greenbrier Co., West Virginia, Matthew L. Niemiller, Michael S. Osbourn, Dante B. Fenolio, Thomas K. Pauley, Brian T. Miller, John R. Holsinger Jan 2010

Conservation Status And Habitat Use Of The West Virginia Spring Salamander (Gyrinophilus Subterraneus) And Spring Salamander (G. Porphyriticus) In General Davis Cave, Greenbrier Co., West Virginia, Matthew L. Niemiller, Michael S. Osbourn, Dante B. Fenolio, Thomas K. Pauley, Brian T. Miller, John R. Holsinger

Biological Sciences Faculty Publications

The West Virginia Spring Salamander (Gyrinophilus subterraneus) is one of four obligate cave-dwelling species of plethodontid salamanders found east of the Mississippi River in the United States. This species is endemic to a single cave system; General Davis Cave, in Greenbrier Co., West Virginia, where it is syntopic with the closely-related Spring Salamander (G. porphyriticus). Accordingly, the West Virginia Spring Salamander is a species of critical conservation concern. Because of it's conservation status and lack of data regarding the ecology and life history, particularly about population trends, we present data on relative abundance of and habitat …


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum Jan 2010

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima, Matthew S. Luchansky, Bryan S. Der, Sabato D'Auria, Gabriella Pocsfalvi, Luisa Iozzion, Daniela Marasco, Jonathan D. Dattelbaum

Chemistry Faculty Publications

Members of the periplasmic binding protein superfamily are involved in the selective passage of ligands through bacterial cell membranes. The hyperthermophilic eubacterium Thermotoga maritima was found to encode a highly stable and specific periplasmic arginine-binding protein (TM0593). Following signal sequence removal and overexpression in Escherichia coli, TM0593 was purified by thermoprecipitation and affinity chromatography. The ultra-stable protein with a monomeric molecular weight of 27.7 kDa was found to exist as both a homodimer and homotrimer at appreciable concentrations even under strongly denaturing conditions, with an estimated transition temperature of 116 °C. Its multimeric structure may provide further evidence of …


Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria Jan 2010

Amino Acid Transport In Thermophiles: Characterization Of An Arginine-Binding Protein In Thermotoga Maritima. 2. Molecular Organization And Structural Stability, Andrea Scirè, Anna Marabotti, Maria Staiano, Luisa Iozzion, Matthew S. Luchansky, Bryan S. Der, Jonathan D. Dattelbaum, Fabio Tanfani, Sabato D'Auria

Chemistry Faculty Publications

ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine …


Plasticity Of Acquired Secondary Metabolites In Clathria Prolifera (Demospongia: Poecilosclerida): Putative Photoprotective Role Of Carotenoids In A Temperate Intertidal Sponge, Jonathan D. Dattelbaum, Drew Sieg, Malcolm Hill, Chris M. Manieri, Giles Thomson Jan 2010

Plasticity Of Acquired Secondary Metabolites In Clathria Prolifera (Demospongia: Poecilosclerida): Putative Photoprotective Role Of Carotenoids In A Temperate Intertidal Sponge, Jonathan D. Dattelbaum, Drew Sieg, Malcolm Hill, Chris M. Manieri, Giles Thomson

Chemistry Faculty Publications

Several marine sponges sequester high concentrations of carotenoids in their tissues. The diversity of carotenoid compounds has been described in detail for a handful of species, but to date, little attention has been paid to natural variability in the concentration and constituency of carotenoid pools. Also lacking are experimental tests of some of the proposed adaptive benefits of carotenoids to the sponge. To address some of these deficits in our understanding of sponge ecology, we used a combination of analytic chemistry, field surveys, and manipulative experiments to determine what function these compounds might play. Attention was focused on the common, …


Chapter 26 – Multiple Color Single Molecule Tirf Imaging And Tracking Of Maps And Motors, Jennifer L. Ross, Ram Dixit Jan 2010

Chapter 26 – Multiple Color Single Molecule Tirf Imaging And Tracking Of Maps And Motors, Jennifer L. Ross, Ram Dixit

Biology Faculty Research

Microtubules are part of a complex mechano-chemical network inside cells. In order to understand how the components of these systems work together, careful in vitro experiments must be performed with added complexity. These experiments can ideally image all the interacting species. In order to image these molecules, multiple-color fluorescence imaging can be performed. In this chapter, we describe some methods for performing multiple-color single molecule fluorescence imaging using total internal reflection fluorescence microscopy. We give several specific examples of species of microtubule-associate proteins and motors that can be examined with detailed protocols for labeling, purification, and imaging.