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Articles 122371 - 122400 of 256036

Full-Text Articles in Life Sciences

Endless Symbioses Most Intricate, W. John Hayden Jul 2016

Endless Symbioses Most Intricate, W. John Hayden

Biology Faculty Publications

Orchids, such as our Wildflower of the Year for 2016, Downy Rattlesnake Plantain (Goodyera pubescens) (Fig. 1), exemplify the interconnectedness of life on Earth. As would be the case for many kinds of plants, pollination comes readily to mind as a prominent example of mutualistic symbiosis. Downy Rattlesnake Plantain is pollinated by bumblebees and other native bees. The bees gain nectar and the orchid gets an efficient means to move pollen from one flower to another; each organism gains benefit from the interaction, the very definition of mutualism. Pollination by bees is widespread among the orchids, but there …


Arsenite Resistance Of Euglena Mutabilis, Nicole Loumarinett Rosendo Mercado, Doug G. Cole (Mentor) Jul 2016

Arsenite Resistance Of Euglena Mutabilis, Nicole Loumarinett Rosendo Mercado, Doug G. Cole (Mentor)

Idaho Conference on Undergraduate Research

Euglena are photosynthetic unicellular protozoa. Commonly found in rivers, lakes and ponds, some Euglena are found in toxic environments, like areas of acid mine drainage where they can grow at low pH and in the presence of heavy metals and metalloids such as arsenite (e.g. Euglena mutabilis). The goal of this research is to determine if an Idaho Euglena isolate (SG6) belongs to the E. mutabilis species and to compare it’s level of arsenite resistance with other E. mutabilis strains. As part of the methodology, we have developed microtiter plate assays in which the cells are …


Proximate And Evolutionary Causes Of Sexual Size Dimorphism In The Crab Spider Mecaphesa Celer, Marie Claire Chelini Jul 2016

Proximate And Evolutionary Causes Of Sexual Size Dimorphism In The Crab Spider Mecaphesa Celer, Marie Claire Chelini

School of Biological Sciences: Dissertations, Theses, and Student Research

Animal species’ body sizes result from the balance between selection for survival and selection for reproduction. In species with sexual size dimorphism (SSD), this balance differs between females and males, resulting in distinct sizes despite similar constraints. I used an integrative approach to understand how sexual section, and differences in developmental trajectories and metabolic physiology, resulted in the female biased SSD of the crab spider Mecaphesa celer (Thomisidae). SSD in spiders is often assumed to be a consequence of selection for early male maturation, which should provide males with additional mating opportunities. My results allow us to discard mate …


Sequencing And Comparative Analysis Of De Novo Genome Assemblies Of Streptomyces Aureofaciens Atcc 10762, Julien S. Gradnigo Jul 2016

Sequencing And Comparative Analysis Of De Novo Genome Assemblies Of Streptomyces Aureofaciens Atcc 10762, Julien S. Gradnigo

School of Biological Sciences: Dissertations, Theses, and Student Research

Streptomyces aureofaciens is a Gram-positive Actinomycete used for commercial antibiotic production. Although it has been the subject of many biochemical studies, no public genome resource was available prior to this project. To address this need, the genome of S. aureofaciens ATCC 10762 was sequenced using a combination of sequencing platforms (Illumina and 454-shotgun). Multiple de novo assembly methods (SGA, IDBA, Trinity, SOAPdenovo2, MIRA, Velvet and SPAdes) as well as combinations of these methods were assessed to determine which provided the most robust assembly. Combination strategies led to a consistent overestimation of the total genome size. Empirical data from targeted …


Lof1 And Interacting Transcription Factors In Plant Development And Crop Yield, Zoe Yeoh, Elizabeth Luscher, Patricia Springer Jul 2016

Lof1 And Interacting Transcription Factors In Plant Development And Crop Yield, Zoe Yeoh, Elizabeth Luscher, Patricia Springer

Student Publications

Transcription factors (TFs) help ensure proper gene expression in developing tissues, and thus play a role in plant development and plant architecture. LATERAL ORGAN FUSION1, or LOF1, is a TF expressed in the organ boundaries of Arabidopsis thaliana. lof1 mutants have fused axillary branches and cauline leaves, which indicates importance in boundary development. Because transcription factors are known to act in complexes, we wanted to discover what other proteins interact with LOF1. We executed a yeast-2-hybrid (Y2H) screen that identified several TFs as potential interactors: WHIRLY 3 (WHY3), MYB DOMAIN PROTEIN32 (MYB32), HOMEOBOX-LEUCINE ZIPPER PROTEIN4 (HB4), and LIGHT RESPONSE BTB2 …


Gray Bat Migration In Missouri, Cheyenne Leigh Gerdes Jul 2016

Gray Bat Migration In Missouri, Cheyenne Leigh Gerdes

Graduate Theses/Dissertations

Migration is an important and understudied aspect of the life histories of many species, particularly bats. Migration impacts conservation efforts, including efforts to manage the impacts of wildlife disease. The federally endangered gray bat (Myotis grisescens) is a migratory species with documented infections by Pseudogymnoascus destructans, the fungus that causes White-nose Syndrome (WNS). To better understand migration as it might relate to WNS, I quantified the timing and location of gray bat movements in Missouri using acoustic detectors and bat banding. I recorded calls at 4 maternity sites from January to May 2015, and used the R package PVAClone to …


Discover And Analysis Of Grapevine Vein-Clearing Virus In Ampelopsis Cordata, Sylvia Marie Petersen Jul 2016

Discover And Analysis Of Grapevine Vein-Clearing Virus In Ampelopsis Cordata, Sylvia Marie Petersen

Graduate Theses/Dissertations

A recent threat to the sustainability of grape production is Grapevine vein-clearing virus (GVCV), the first DNA virus discovered in grapevines. Infection with GVCV leads to vine decline, lower quality berries, and eventual death of the grapevine. Since GVCV was discovered in cultivated grapevines, research has been dedicated to investigating its range and origin. The entire genome of the first GVCV isolate from a grape cultivar ‘Chardonel' has been deposited in GenBank and is used as a reference genome. More recently, two GVCV isolates were found in native Vitis rupestris in Missouri. In this thesis project, I applied polymerase chain …


Protein And Exercise Effects On The Musculature Of The Back In Horses, Taryn Elizabeth Smith Jul 2016

Protein And Exercise Effects On The Musculature Of The Back In Horses, Taryn Elizabeth Smith

Graduate Theses/Dissertations

This study was designed to examine the effects of exercise on the musculature of the back of ten horses which are used to teach beginning through advanced horsemanship. This was executed by implementing a strict exercise protocol, examining body composition changes and subjecting them to a standard exercise test at the beginning and end of the experimental period in order to determine change in aerobic conditioning. Horses were randomly assigned to one of two treatment groups for six weeks; Purina SuperSportTM (40% CP) and MFA Easy Keeper™ (32% CP). Body weight (BW), body condition score (BCS), rump fat, topline evaluation …


Functional Analysis Of Grapevine Sts7 And Sts22 Promoters, Lianhua Lianhua Xu Jul 2016

Functional Analysis Of Grapevine Sts7 And Sts22 Promoters, Lianhua Lianhua Xu

Graduate Theses/Dissertations

Stilbenic compounds are a group of phytoalexins that are produced by a limited number of plant species including grapevine to defend against diseases. Stilbene synthase (STS) is the key enzyme that catalyzes the biosynthesis of stilbenic compounds. Previous results indicated a significant increase in the abundance of transcripts of STS7 and STS22 genes in powdery mildew-infected Cabernet Sauvignon leaves. I isolated the promoter sequences of STS7 and STS22 from grapevine Vitis aestivalis "Norton"(Va) and Vitis vinifera "Cabernet Sauvignon"(Vv) and studied their activities in transgenic plants. The results showed high activity of VaSTS7 and VaSTS22 promoters in transgenic plant leaves at …


Sunlight Induced Chlorophyll Fluorescence In The Near-Infrared Spectral Region In Natural Waters: Interpretation Of The Narrow Reflectance Peak Around 761 Nm, Yingcheng Lu, Linhai Li, Chuanmin Hu, Lin Li, Minwei Zhang, Shaojie Sun, Chunguang Lv Jul 2016

Sunlight Induced Chlorophyll Fluorescence In The Near-Infrared Spectral Region In Natural Waters: Interpretation Of The Narrow Reflectance Peak Around 761 Nm, Yingcheng Lu, Linhai Li, Chuanmin Hu, Lin Li, Minwei Zhang, Shaojie Sun, Chunguang Lv

Marine Science Faculty Publications

Sunlight induced chlorophyll a fluorescence (SICF) can be used as a probe to estimate chlorophyll a concentrations (Chl) and infer phytoplankton physiology. SICF at ∼685 nm has been widely applied to studies of natural waters. SICF around 740 nm has been demonstrated to cause a narrow reflectance peak at ∼761 nm in the reflectance spectra of terrestrial vegetation. This narrow peak has also been observed in the reflectance spectra of natural waters, but its mechanism and applications have not yet been investigated and it has often been treated as measurement artifacts. In this study, we aimed to interpret …


Anal Fin Pigmentation In Brachyrhaphis Fishes Is Not Used For Sexual Mimicry, Kandace Mary Hugentobler Jul 2016

Anal Fin Pigmentation In Brachyrhaphis Fishes Is Not Used For Sexual Mimicry, Kandace Mary Hugentobler

Theses and Dissertations

Pigmentation patterns can be used as a communication signal in a variety of taxa, and can convey information relative to sexual selection, dominance, and species identification. Pigmentation is also sometimes used in mimicry to deceive the signal receiver into thinking the signaler is something other than itself. Mimicry can occur in several contexts, including sexual interactions, where one sex mimics another. There are relatively few examples of species with females that mimic males. Proposed hypotheses to explain female mimicry of males are that mimicry is used to reduce male harassment or that mimicry is used to display dominance over other …


The Activity Of Alkaline Glutaraldehyde Against Bacterial Endospores And Select Non-Enveloped Viruses, Justen Thalmus Despain Jul 2016

The Activity Of Alkaline Glutaraldehyde Against Bacterial Endospores And Select Non-Enveloped Viruses, Justen Thalmus Despain

Theses and Dissertations

Alkaline glutaraldehyde (GTA) has been used as a high level chemical disinfectant and sterilant for many years and is known to kill a broad spectrum of organisms ranging from vegetative eukaryotes to bacterial endospores. Although the mechanism of sporicidal action has been studied on numerous occasions, GTA's exact mechanism(s) of action are still debated. In addition to the uncertainty of GTA's mechanism(s) of action, GTA has also shown significant variability in the time required to kill endospores and naked viruses. A better knowledge of the lethal mechanism(s) of GTA is needed to understand this discrepancy in kill times for GTA …


Walking Behavior Of Zoo Elephants: Associations Between Gps-Measured Daily Walking Distances And Environmental Factors, Social Factors, And Welfare Indicators, Matthew Robert Holdgate, Cheryl L. Meehan, Jennifer N. Hogan, Lance J. Miller, Josesph Soltis, Jeff Andrews, David J. Shepherdson Jul 2016

Walking Behavior Of Zoo Elephants: Associations Between Gps-Measured Daily Walking Distances And Environmental Factors, Social Factors, And Welfare Indicators, Matthew Robert Holdgate, Cheryl L. Meehan, Jennifer N. Hogan, Lance J. Miller, Josesph Soltis, Jeff Andrews, David J. Shepherdson

Biology Faculty Publications and Presentations

Research with humans and other animals suggests that walking benefits physical health. Perhaps because these links have been demonstrated in other species, it has been suggested that walking is important to elephant welfare, and that zoo elephant exhibits should be designed to allow for more walking. Our study is the first to address this suggestion empirically by measuring the mean daily walking distance of elephants in North American zoos, determining the factors that are associated with variations in walking distance, and testing for associations between walking and welfare indicators. We used anklets equipped with GPS data loggers to measure outdoor …


Reclaiming The Activity Of Lost Therapeutics, Rallya Telussa Jul 2016

Reclaiming The Activity Of Lost Therapeutics, Rallya Telussa

USF Tampa Graduate Theses and Dissertations

ESKAPE pathogens are notorious in causing nosocomial infections and escaping current antibiotic treatments. There has been a dramatic increase in nosocomial infections accompanied with a decrease in the number of antibiotics developed, leading to significant increase in morbidity and mortality among patients. In an attempt to combat this problem, derivatives of ciprofloxacin, rifabutin and beta-lactam antibiotics were synthesized and tested against the ESKAPE pathogens. From minimum inhibitory concentration assays, 4 ciprofloxacin analogs and 8 beta-lactam analogs were found to be effective against multiple bacterial species. Additionally, 12 rifabutin analogs and 23 beta-lactam analogs were potent against single bacterial species, primarily …


Radial Glia Inhibit Peripheral Glial Infiltration Into The Spinal Cord At Motor Exit Point Transition Zones, Cody J. Smith, Kimberly Johnson, Taylor G. Welsh, Michael J.F. Barresi, Sarah Kucenas Jul 2016

Radial Glia Inhibit Peripheral Glial Infiltration Into The Spinal Cord At Motor Exit Point Transition Zones, Cody J. Smith, Kimberly Johnson, Taylor G. Welsh, Michael J.F. Barresi, Sarah Kucenas

Biological Sciences: Faculty Publications

In the mature vertebrate nervous system, central and peripheral nervous system (CNS and PNS, respectively) GLIA myelinate distinct motor axon domains at the motor exit point transition zone (MEP TZ). How these cells preferentially associate with and myelinate discrete, non-overlapping CNS versus PNS axonal segments, is unknown. Using in vivo imaging and genetic cell ablation in zebrafish, we demonstrate that radial glia restrict migration of PNS glia into the spinal cord during development. Prior to development of radial glial endfeet, peripheral cells freely migrate back and forth across the MEP TZ. However, upon maturation, peripherally located cells never enter the …


Microbubble Generation By Piezoelectric Transducers For Biomedical Studies, Mohammed Alkhazal Jul 2016

Microbubble Generation By Piezoelectric Transducers For Biomedical Studies, Mohammed Alkhazal

Electrical & Computer Engineering Theses & Dissertations

Bubbles induced by blast waves or shocks are speculated as the major cause of damage in biological cells in mild traumatic brain injuries (TBI). Microbubble collapse was found to induce noticeable cell detachment from the cell substrate, changes in focal adhesion, and biomechanics. To better understand the bubble mechanism, a system needs to be constructed which allows clear differentiation on the impact of bubbles from that of shocks. Such a generator needs to be low profile in order to place under a microscope. A piezoelectric transducer system was designed to meet the need. The system uses either a flat or …


Assessment Of Indoor And Outdoor Pm Species At Schools And Residences In A High-Altitude Ecuadorian Urban Center, Amit U. Raysoni, Rodrigo X. Armijos, M. Margaret Weigel, Teresa Montoya, Patricia Eschanique, Marcia Racines, Wen-Whai Li Jul 2016

Assessment Of Indoor And Outdoor Pm Species At Schools And Residences In A High-Altitude Ecuadorian Urban Center, Amit U. Raysoni, Rodrigo X. Armijos, M. Margaret Weigel, Teresa Montoya, Patricia Eschanique, Marcia Racines, Wen-Whai Li

School of Earth, Environmental, & Marine Sciences Faculty Publications

An air monitoring campaign to assess children’s environmental exposures in schools and residences, both indoors and outdoors, was conducted in 2010 in three low-income neighborhoods in Z1(north), Z2(central), and Z3(southeast) zones of Quito, Ecuador - a major urban center of 2.2 million inhabitants situated 2850 meters above sea level in a narrow mountainous basin. Z1 zone, located in northern Quito, historically experienced emissions from quarries and moderate traffic. Z2 zone was influenced by heavy traffic in contrast to Z3 zone which experienced low traffic densities. Weekly averages of PM samples were collected at schools (one in each zone) and residences …


Supercomplex-Associated Cox26 Protein Binds To Cytochrome C Oxidase, Valentina Strecker, Zibirnisa Kadeer, Juliana Heidler, Cristina-Maria Cruciat, Heike Angerer, Heiko Giese, Kathy Pfeiffer, Rosemary A. Stuart, Ilka Wittig Jul 2016

Supercomplex-Associated Cox26 Protein Binds To Cytochrome C Oxidase, Valentina Strecker, Zibirnisa Kadeer, Juliana Heidler, Cristina-Maria Cruciat, Heike Angerer, Heiko Giese, Kathy Pfeiffer, Rosemary A. Stuart, Ilka Wittig

Biological Sciences Faculty Research and Publications

Here we identified a hydrophobic 6.4 kDa protein, Cox26, as a novel component of yeast mitochondrial supercomplex comprising respiratory complexes III and IV. Multi-dimensional native and denaturing electrophoretic techniques were used to identify proteins interacting with Cox26. The majority of the Cox26 protein was found non-covalently bound to the complex IV moiety of the III–IV supercomplexes. A population of Cox26 was observed to exist in a disulfide bond partnership with the Cox2 subunit of complex IV. No pronounced growth phenotype for Cox26 deficiency was observed, indicating that Cox26 may not play a critical role in the COX enzymology, and we …


Genome Engineering In Mammalian Cells By Flp And Cre Dna Recombinase Variants, Riddhi Shah Jul 2016

Genome Engineering In Mammalian Cells By Flp And Cre Dna Recombinase Variants, Riddhi Shah

Doctoral Dissertations

Genome engineering relies on DNA modifying enzymes that are able to locate a DNA sequence of interest and initiate a desired genome rearrangement. Currently, the field predominantly utilizes site-specific DNA nucleases that depend on the host DNA repair machinery to complete a genome modification task. We show here that genome engineering approaches that employ self-sufficient, versatile site-specific DNA recombinase Flp and Cre can be developed into promising alternatives. We demonstrate that a Flp variant evolved to recombine an FRT-like sequence FL-IL10A, which is located upstream of the human interleukin-10 gene, can target this sequence in the model setting and native …


Nano Clay-Enhanced Calcium Phosphate Cements And Hydrogels For Biomedical Applications, Udayabhanu Jammalamadaka Jul 2016

Nano Clay-Enhanced Calcium Phosphate Cements And Hydrogels For Biomedical Applications, Udayabhanu Jammalamadaka

Doctoral Dissertations

Biomaterials are used as templates for drug delivery, scaffolds in tissue engineering, grafts in surgeries, and support for tissue regeneration. Novel biomaterial composites are needed to meet multifaceted requirements of compatibility, ease of fabrication and controlled drug delivery. Currently used biomaterials in orthopedics surgeries suffer limitations in toxicity and preventing infections. Polymethyl methacrylate (PMMA) used as bone cement suffers from limitations of thermal necrosis and monomer toxicity calls for development of better cementing biomaterials. A biodegradable/bioresorbable cement with good mechanical properties is needed to address this short coming. Metal implants used in fixing fractures or total joint replacement needs improvements …


Rna-Seq Analysis Of Localized Mst1/Stk4 Expression In Prostate Cancer, Damien Ready Jul 2016

Rna-Seq Analysis Of Localized Mst1/Stk4 Expression In Prostate Cancer, Damien Ready

Master's Theses (2009 -)

The SKT4-encoded MST1 is a serine-threonine protein kinase and has known associations with many diseases and cancer.MST1 plays a critical component of the Hippo tumor suppressor pathway responsible for limiting cell division and promoting apoptosis.Loss of MST1 function is associated with poor prognostic outcomes for cancers, though the mechanism is not well understood.There is increasing evidence that dysregulation of MST1 can lead to castration-resistant prostate cancer (CRPCa), an aggressive cancer with limited treatment options.To better understand the mechanistic underpinnings of CRPCa progression, C4-2 prostate cancer cells were engineered toexpress MST1 protein directed to a particular subcellular region: membrane, nucleus, or …


The Effect Of Fasted Vs Fed High-Intensity Interval Exercise On Metabolism And Diet, William Joseph Perez Jul 2016

The Effect Of Fasted Vs Fed High-Intensity Interval Exercise On Metabolism And Diet, William Joseph Perez

Human Movement Studies & Special Education Theses & Dissertations

The purpose of this study was to investigate immediate and delayed metabolic and dietary responses to a single bout of cycling high-intensity interval exercise (HIIE) performed in the fasted and fed state. Baseline values of 11 subjects (6 female, 5 male) for resting energy expenditure (REE), respiratory exchange ratio (RER), resting VO2, VO2max and appetite score (VAS) were measured on the first visit. Energy balance (EB) was determined using diet tracking and activity energy expenditure (paEE). Trials followed a day at net energy balance and began in a fasted state. A 240-kcal energy bar was consumed prior …


Hotspots, Extinction Risk And Conservation Priorities Of Greater Caribbean And Gulf Of Mexico Marine Bony Shorefishes, Christi Linardich Jul 2016

Hotspots, Extinction Risk And Conservation Priorities Of Greater Caribbean And Gulf Of Mexico Marine Bony Shorefishes, Christi Linardich

Biological Sciences Theses & Dissertations

Understanding the status of species is important for allocation of resources to redress biodiversity loss. Regional organizations tasked with managing threats to the 1,360 marine bony shorefishes of the Caribbean and Gulf of Mexico would benefit from a delineation of conservation priorities. However, prior to this study, conservation status was known for only one quarter of these shorefishes. Extinction risk assessment under IUCN Red List Criteria is a widely-used, objective method to communicate species-specific conservation needs. Data were collated on each species’ distribution, population, habitats and threats and experts at three Red List workshops assigned a global level extinction risk …


Redescription Of Helorus Ruficornis Förster (Hymenoptera: Heloridae), With A New Synonymy And New Afrotropical Specimen Records, Matthew L. Buffington, Robert S. Copeland Jul 2016

Redescription Of Helorus Ruficornis Förster (Hymenoptera: Heloridae), With A New Synonymy And New Afrotropical Specimen Records, Matthew L. Buffington, Robert S. Copeland

All Peer-Reviewed Publications

Research up to this point has recorded two species of Afrotropical Heloridae: Helorus ruficornis Förster and H. elgoni Risbec. After examining recently collected specimens from Kenya and Burundi, we have been able to better understand intraspecific variation within Helorus ruficornis, and as a result, we hereby synonymize H. elgoni with H. ruficornis, redescribe H. ruficornis, and illustrate the holotype of H. elgoni for the first time. We also discuss new collection records for Afrotropical Heloridae, as well as possible habitat preferences.


An Indirect Defence Trait Mediated Through Egg-Induced Maize Volatiles From Neighbouring Plants, Daniel M. Mutyambai, Toby J.A. Bruce, Johnnie Van Den Berg, Charles A.O. Midega, John A. Pickett, Zeyaur R. Khan Jul 2016

An Indirect Defence Trait Mediated Through Egg-Induced Maize Volatiles From Neighbouring Plants, Daniel M. Mutyambai, Toby J.A. Bruce, Johnnie Van Den Berg, Charles A.O. Midega, John A. Pickett, Zeyaur R. Khan

All Peer-Reviewed Publications

Attack of plants by herbivorous arthropods may result in considerable changes to the plant's chemical phenotype with respect to emission of herbivore-induced plant volatiles (HIPVs). These HIPVs have been shown to act as repellents to the attacking insects as well as attractants for the insects antagonistic to these herbivores. Plants can also respond to HIPV signals from other plants that warn them of impending attack. Recent investigations have shown that certain maize varieties are able to emit volatiles following stemborer egg deposition. These volatiles attract the herbivore's parasitoids and directly deter further oviposition. However, it was not known whether these …


Push-Pull: Chemical Ecology-Based Integrated Pest Management Technology, Zeyaur Khan, Charles A.O. Midega, Antony Hooper, John Pickett Jul 2016

Push-Pull: Chemical Ecology-Based Integrated Pest Management Technology, Zeyaur Khan, Charles A.O. Midega, Antony Hooper, John Pickett

All Peer-Reviewed Publications

Lepidopterous stemborers, and parasitic striga weeds belonging to the family Orobanchaceae, attack cereal crops in sub-Saharan Africa causing severe yield losses. The smallholder farmers are resource constrained and unable to afford expensive chemicals for crop protection. The push–pull technology, a chemical ecology- based cropping system, is developed for integrated pest and weed management in cereal–livestock farming systems. Appropriate plants were selected that naturally emit signaling chemicals (semiochemicals). Plants highly attractive for stemborer egg laying were selected and employed as trap crops (pull), to draw pests away from the main crop. Plants that repelled stemborer females were selected as intercrops (push). …


Maize Response To Macronutrients And Potential For Profitability In Sub-Saharan Africa, J. Kihara, J. Huising, G. Nziguheba, B. S. Waswa, S. Njoroge, V. Kabambe, E. Iwuafor, C. Kibunja, A. O. Esilaba, A. Coulibaly Jul 2016

Maize Response To Macronutrients And Potential For Profitability In Sub-Saharan Africa, J. Kihara, J. Huising, G. Nziguheba, B. S. Waswa, S. Njoroge, V. Kabambe, E. Iwuafor, C. Kibunja, A. O. Esilaba, A. Coulibaly

All Peer-Reviewed Publications

Sub-Saharan Africa (SSA) is plagued by low productivity and little research is available on the attainable responses and profitability to applied nutrients under variable environments. The objective of this study was to determine the attainable maize grain response to and potential of profitability of N, P and K application in SSA using boundary line approaches. Data from experiments conducted in SSA under AfSIS project (2009–2012) and from FAO trials database (1969–1996) in 15 countries and constituting over 375 different experimental locations and 6600 data points are used. Both response to fertilizer and value cost ratio (VCR) are highly variable and …


More Crop Per Drop: Benchmarking On-Farm Irrigation Water Use For Crop Production., Katherine Elizabeth Boone Gibson Jul 2016

More Crop Per Drop: Benchmarking On-Farm Irrigation Water Use For Crop Production., Katherine Elizabeth Boone Gibson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Efficient use of irrigation is essential to meet food production needs of growing global populations while ensuring long-term sustainability of freshwater resources. However, lack of on-farm irrigation data constrains understanding of irrigation variation and no framework exists to benchmark irrigation use using actual irrigation data. The following work investigates variation in irrigation using a database of ca. 1400 maize and soybean fields over 9 years in Nebraska and presents a framework to benchmark irrigation use using a separate database of ca. 1000 maize and soybean fields in Nebraska as proof of concept. “State-of-the-art” crop models estimated yield potential and irrigation …


Behavioral Responses Of Ringed And Spotted Salamanders To Diet-Related Cues From Predators, Kayla Shelton Jul 2016

Behavioral Responses Of Ringed And Spotted Salamanders To Diet-Related Cues From Predators, Kayla Shelton

Graduate Theses/Dissertations

Multiple species of Ambystoma can sometimes coexist in ponds, often forming a prey guild. In the Ozarks, ringed salamanders (Ambystoma annulatum) can coexist with marbled salamanders (A. opacum) and spotted salamanders (A. maculatum). Ringed and marbled salamanders lay their eggs in ponds in the fall and overwinter as larvae, whereas spotted salamanders breed in the spring. Ringed and marbled salamander larvae can be cannibalistic and can prey upon larvae of the other two species. Larvae should experience increased survival if they can discriminate between predators that have recently consumed another salamander (high risk) versus those that have not (low risk). …


High Tunnel Production Of Primocane Bearing Red Raspberries In Grow Bags, Jennifer Sue Morganthaler Jul 2016

High Tunnel Production Of Primocane Bearing Red Raspberries In Grow Bags, Jennifer Sue Morganthaler

Graduate Theses/Dissertations

Raspberries (Rubus idaeus) are a perennial crop with increasing consumer demand. While this highly perishable crop has not proven to be a commercially viable field grown crop in the Midwest, it does show increased yields when grown in a high tunnel. High tunnel construction in Missouri has increased partly due to the NRCS grant program. However, high tunnel production permanently utilizes that space. Bagged culture allows growers the ability to maximize high tunnel space and produce other annual crops, while testing the performance of the crop for their production. This 4 year trial evaluates 5 primocane bearing red raspberries cultivars …