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Does Riparian Forest Invasion By The Exotic Shrub Amur Honeysuckle Influence Nutrient Dynamics In Headwater Streams?, Charlotte Anne Shade

Honors Theses

Lonicera maackii (Amur honeysuckle) invasion is extensive in forests across much of Ohio and the Midwest. Amur honeysuckle has been shown to influence headwater streams and its organisms, which depend on a certain water chemistry to survive. Little has been done to understand how honeysuckle affects water chemistry and nutrient cycling. As honeysuckle canopies prevent native organic matter from entering the streams below, while also adding its own organic matter that is high in nitrogen and phosphorus, and low in lignin, the amount and types of nutrients present in both forests and streams may be significantly altered. Over a one-year …

The Arabidopsis Kinesin-4, Fra1, Requires A High Level Of Processive Motility To Function Correctly, Anindya Ganguly, Logan Demott, Ram Dixit

Biology Faculty Research

Processivity is important for kinesins that mediate intracellular transport. Structure–function analyses of N-terminal kinesins (i.e. kinesins comprising their motor domains at the N-terminus) have identified several non-motor regions that affect processivity in vitro. However, whether these structural elements affect kinesin processivity and function in vivo is not known. Here, we used an Arabidopsis thaliana kinesin-4, called Fragile Fiber 1 (FRA1, also known as KIN4A), which is thought to mediate vesicle transport, to test whether mutations that alter processivity in vitro lead to similar changes in behavior in vivo and whether processivity is important for the function of FRA1. We …

Detecting, Cloning, And Screening For Suppressors Of Rna Silencing In Maize Chlorotic Mottle Virus And Sugarcane Mosaic Virus, Nicole E. Bacheller

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

Maize lethal necrosis disease (MLND) is one of the most important viral diseases of maize. MLND occurs when Maize chlorotic mottle virus (MCMV) co-infects the same plant with one of several potyviruses, including Sugarcane mosaic virus, Wheat streak mosaic virus or Maize dwarf mosaic virus. Originally prevalent in the Midwest and Peru in the 1970s, the disease was called corn lethal necrosis (CLN) and was controlled through breeding and sanitation. Recently, the disease has re-emerged in East Africa and is rapidly spreading and threatening the food sources of subsistence-farming populations. This re-emergence has raised several questions about the unknown …

Surveying The Distributions Of Melaleuca Quinquenervia, Psidium Cattleianum, And Litsea Glutinosa At Analalava Special Reserve, Hanusia Higgins

Independent Study Project (ISP) Collection

This study surveyed the distributions of three invasive plant species, Melaleuca quinquenervia, Psidium cattleianum, and Litsea glutinosa at the Analalava Special Reserve in Mahavelona, Madagascar. Analalava is a 229-hectare degraded patch of low-elevation humid forest on the northeast coast of Madagascar, and one of the last forest fragments remaining in the region. It is a haven for biodiversity, containing 343 recorded species of plants, 12 of which are locally endemic. Invasive species are considered the second-most significant threat to biodiversity, both worldwide and specifically at Analalava. Based on a systematic transect survey of these three targeted invasive species, their distributions …

The Taxonomy, Reproduction, And Distribution Of Rare Plants: A Study Of Magnolia Sp. In The Río Zuñac Reserve, Ecuador, Alyssa Kullberg

Independent Study Project (ISP) Collection

Ecuadorian cloud forests are biodiversity hotspots and centers of unprecedented levels of endemism, but they are also under-researched and under-protected. This study took place in the Río Zuñac Reserve, which is a reserve of about 850 ha located in the Tungurahua province of Ecuador, and is home to at least 20 endemic plant species. Three new species of Magnolia have been discovered in this reserve in the past five years: Magnolia llanganates, Magnolia vargasiana, and one species that has yet to be formally described. This study dealt with accurately locating and describing new individuals of these species over the …

Investigation De Regeneración Natural De Plantas Vasculares En La Reserva Madrigal Del Podocarpus / Investigation Of Natural Regeneration Of Vascular Plants In The Madrigal Reserve Of The Podocarpus, Sy Baker

Independent Study Project (ISP) Collection

En el Sur de Ecuador, hay una historia larga de incendio que está asociada con la historia de la agricultura y ganadería a causa de las técnicas de tala y quema para despejar áreas para campos y también quemaduras intencionales para fertilizar los suelos y mejorar productividad agrícola (Fernandez et al 2015). En los últimos días de Noviembre de 2016, un incendio quemó campos, la Reserva Madrigal de Podocarpus, y parte del Parque Nacional Podocarpus en Loja, Ecuador—el enfoque de este estudio. En este estudio: (1) se registraron las especies y distribución de plantas pioneras y sobrevivientes, (2) la se …

Growing South Dakota (Spring 2017), College Of Agriculture &. Biological Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

This issue contains the 2016 South Dakota Agricultural Experiment Station Annual Report.

[Page] 3 Opportunities With Oats SDSU Researchers Strive to Improve Varieties [Page] 6 Stopping Stem Canker Plant Pathologists Making Progress To Keep This Disease At Bay
[Page] 7 Disease Detectives Vet Scientists Researching Another Emerging Virus [Page] 8 Community Support Devastating West River Fire Brings Ag Industry Together
[Page] 10 Research In Progress Dakota Lakes Research Farm Investigates Three Big Ideas
[Page] 14 Water Quality Quest Understanding E. Coli Behavior Aims To Aid Water Quality In Rivers & Streams
[Page] 15 Verifying Ag Land Valuation Researchers Assist In …

Emergence, Competition, And Management Of Glyphosate-Resistant Common Ragweed (Ambrosia Artemisiifolia L.) In Nebraska Soybean, Ethann R. Barnes

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

Common ragweed (Ambrosia artemisiifolia L.) is a competitive annual broadleaf weed in soybean (Glycine max) production fields throughout North America. The recent confirmation of glyphosate-resistant common ragweed in Nebraska justified the need to assess the emergence pattern and competitive ability of common ragweed in soybean and to evaluate alternative herbicide programs for effective management. The objectives of this research were to: 1) evaluate the effect of tillage and develop a predictive model for the emergence pattern of common ragweed in Nebraska; 2) model the competitive interaction between soybean and common ragweed as influenced by density and irrigation …

Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani

Department of Geography: Dissertations, Theses, and Student Research

The gross primary production (GPP) metric is useful in determining trends in the terrestrial carbon cycle. Models that determine GPP utilizing the light use efficiency (LUE) approach in conjunction with biophysical parameters that account for local weather conditions and crop specific factors are beneficial in that they combine the accuracy of the biophysical model with the versatility of the LUE model. One such model developed using in situ data was adapted to operate with remote sensing derived leaf area index (LAI) data and gridded weather datasets. The model, known as the Light Use Efficiency GPP Model (EGM), uses a four …

Foraging Behavior Of Spring Bees And Their Agricultural Implications, Michael D. Gregory

Biological Sciences Theses & Dissertations

Colony Collapse Disorder has greatly reduced honey bee populations in the last decade. Native bees have been largely neglected in research, and their floral preferences may have agricultural implications because native bees ameliorate the demand to rely solely on non-native bees. In this work, pollinator visitation to flowers with manipulated ultraviolet floral patterns was monitored. Populations of wild showy golden-eye in Colorado, plus cultivar populations of black-eyed Susan and lawn populations of buttercups in Virginia were monitored for pollinator landings to compare preference for unmanipulated ultraviolet-absorptive floral guide preferences. Another number, a proxy for pollen load, was manipulated on strawberry …

Hairy Root Transgene Expression Analysis Of A Secretory Peroxidase (Pvpox1) From Common Bean Infected By Fusarium Wilt, Renfeng Xue, Xingbo Wu, Yingjie Wang, Yan Zhuang, Jian Chen, Jing Wu, Weide Ge, Lanfen Wang, Shumin Wang, Matthew W. Blair

Agricultural and Environmental Sciences Faculty Research

Plant peroxidases (POXs) are one of the most important redox enzymes in the defense responses. However, the large number of different plant POX genes makes it necessary to carefully confirm the function of each paralogous POX gene in specific tissues and disease interactions. Fusarium wilt is a devastating disease of common bean caused by Fusarium oxysporum f. sp. phaseoli. In this study, we evaluated a peroxidase gene, PvPOX1, from a resistant common bean genotype, CAAS260205 and provided direct evidence for PvPOX1’s role in resistance by transforming the resistant allele into a susceptible common bean genotype, BRB130, via hairy root transformation …

Assessing Productivity In Prairie Biomass Feedstocks With Different Levels Of Diversity, Alyssa Williams, Mark E. Sherrard

Research in the Capitol

High-diversity mixtures of tallgrass prairie vegetation provide many ecosystem services and could be effective biomass feedstocks for marginal farmland in Iowa. In this study, we measured productivity in four prairie biomass feedstocks with different diversity: 1, 5, 16, and 32 species. Each feedstock was replicated four times on three soil types (48 research plots, 0.33 – 0.56 ha each). For the past seven years, we have monitored productivity in these feedstocks by harvesting tissue from randomly selected quadrats. In addition to continuing the productivity survey, we examined the efficacy of remote sensing (NDVI) and leaf area index (LAI) imaging for …

A Comparison Of Water Potential, Photosynthetic Rate, Electron Transport Rate, And Stomatal Conductance Between Native Malosma Laurina And Exotic Schinus Molle, Karagan L. Smith, Agatha C. Heng, Viridiana Hernandez-Lopez

Seaver College Research And Scholarly Achievement Symposium

A Comparison of Water Potential, Photosynthetic Rate, Electron Transport Rate, and Stomatal Conductance between Native Malosma laurina and Exotic Schinus molle

Karagan L. Smith, Agatha C. Heng, and Viridiana Hernandez-Lopez

First-year Students as Scholars Program

Mentors: Natalie M. Aguirre, Kaitlyn E. Sauer, and Stephen D. Davis

Schinus molle is a relatively new invasive species in chaparral shrub communities of the Santa Monica Mountains, and has only recently been observed to displace native species of shrubs, such as Malosma laurina. To investigate the probably cause of S. molle’s invasiveness and mechanisms of competitive displacement of M. laurina, we compared …

Effect Of Drought On Resin Production In Woody Stems Of Rhus Ovata, Sydney T. Adams, Melody Young, Moriah Hall

Seaver College Research And Scholarly Achievement Symposium

Resin production in stems of woody plants is generated from resin canal secretions and is thought to play a significant role in protection from fungal infection and spread. This may be one of several factors associated with fungal infection and fungal induced dieback in plants during severe water stress or drought. We set out to determine if reduction in resin production in a chaparral shrub, Sugar Bush (Rhus ovata), was associated with severe drought in southern California. We hypothesized that dehydrated R. ovata would produce less resin than hydrated plants. Our null hypothesis was that there is no …

Comparison Of Leaf Water Potential, Stomatal Conductance, And Chlorophyll Fluorescence Between An Invasive Weed, Schinus Molle, And A Native Chaparral Shrub, Ceanothus Spinosus, In The Santa Monica Mountains, Adam L. Fahey, Harry Zhou, Katie Callahan

Seaver College Research And Scholarly Achievement Symposium

The Peruvian peppertree, Schinus molle, is an invasive species in California that has escaped cultivation to competitively exclude native species in the landscape. One example of such competition is between a dominant member of the chaparral shrub community, greenbark ceanothus (Ceanothus spinosus), and S. molle. The mechanism of competitive displacement of chaparral by S. molle is not understood nor has it been previously studied. We hypothesized that during severe drought, such as occurred during the sumer/fall of 2016, S. molle would have a more favorable water balance then its native competitor C. spinosus, eventually leading to higher survival and species …

Hydraulic Mechanisms Of Fungal-Induced Dieback In A Keystone Chaparral Species During Unprecedented Drought In California, Natalie M. Aguirre, Marissa E. Ochoa, Helen I. Holmlund, Frank E. Ewers, Stephen D. Davis

Seaver College Research And Scholarly Achievement Symposium

Between 2012-2016, southern California experienced unprecedented drought that caused dieback in Malosma laurina, a keystone species of chaparral shrub communities. Dieback was especially severe in coastal exposures of the Santa Monica Mountains, leading to whole plant mortality exceeding 50% at some sites. We hypothesized that the endophytic fungus causing the dieback, Botryosphaeria dothidea, was successful in invading the xylem tissue of M. laurina because of protracted water stress, carbon starvation, or a combination of the two. We tested these possibilities in a controlled pot experiment by comparing three treatments, each inoculated with the fungus: (1) irrigated controls (2) …

Virus-Mediated Suppression Of Host Non-Self Recognition Facilitates Horizontal Transmission Of Heterologous Viruses, Songsong Wu, Jiasen Cheng, Yanping Fu, Tao Chen, Daohong Jiang, Said A. Ghabrial, Jiatao Xie

Plant Pathology Faculty Publications

Non-self recognition is a common phenomenon among organisms; it often leads to innate immunity to prevent the invasion of parasites and maintain the genetic polymorphism of organisms. Fungal vegetative incompatibility is a type of non-self recognition which often induces programmed cell death (PCD) and restricts the spread of molecular parasites. It is not clearly known whether virus infection could attenuate non-self recognition among host individuals to facilitate its spread. Here, we report that a hypovirulence-associated mycoreovirus, named Sclerotinia sclerotiorum mycoreovirus 4 (SsMYRV4), could suppress host non-self recognition and facilitate horizontal transmission of heterologous viruses. We found that cell death in …

Species Delimitation And Lineage Separation History Of A Species Complex Of Aspens In China, Honglei Zheng, Liqiang Fan, Richard I. Milne, Lei Zhang, Yaling Wang, Kangshan Mao

Aspen Bibliography

Species delimitation in tree species is notoriously challenging due to shared polymorphisms among species. An integrative survey that considers multiple operational criteria is a possible solution, and we aimed to test it in a species complex of aspens in China. Genetic [four chloroplast DNA (cpDNA) fragments and 14 nuclear microsatellite loci (nSSR)] and morphological variations were collected for 76 populations and 53 populations, respectively, covering the major geographic distribution of the Populus davidiana-rotundifoliacomplex. Bayesian clustering, analysis of molecular variance (AMOVA), Principle Coordinate Analysis (PCoA), ecological niche modeling (ENM), and gene flow (migrants per generation), were employed to …

Odor, Not Performance, Dictates Bemisia Tabaci'S Selection Between Healthy And Virus Infected Plants, Gong Chen, Qi Su, Xiaobin Shi, Xin Liu, Zhengke Peng, Huixin Zheng, Wen Xie, Baoyun Xu, Shaoli Wang, Qingjun Wu, Xuguo Zhou, Youjun Zhang

Entomology Faculty Publications

Although, insect herbivores are generally thought to select hosts that favor the fitness of their progeny, this “mother-knows-best” hypothesis may be challenged by the presence of a plant virus. Our previous study showed that the whitefly, Bemisia tabaci, the obligate vector for transmitting Tomato yellow leaf curl virus (TYLCV), preferred to settle and oviposit on TYLCV-infected rather than healthy host plant, Datura stramonium. The performances of B. tabaci larvae and adults were indeed improved on virus-infected D. stramonium, which is consistent with “mother-knows-best” hypothesis. In this study, B. tabaci Q displayed the same preference to settle and …

Draft Genome Sequence Of Cercospora Sojina Isolate S9, A Fungus Causing Frogeye Leaf Spot (Fls) Disease Of Soybean, Fanchang Zeng, Chaofan Wang, Guirong Zhang, Junmei Wei, Carl A. Bradley, Ray Ming

Plant Pathology Faculty Publications

Fungi are the causal agents of many of the world's most serious plant diseases causing disastrous consequences for large-scale agricultural production. Pathogenicity genomic basis is complex in fungi as multicellular eukaryotic pathogens. The fungus Cercospora sojina is a plant pathogen that threatens global soybean supplies. Here, we report the genome sequence of C. sojina strain S9 and detect genome features and predicted genomic elements. The genome sequence of C. sojina is a valuable resource with potential in studying the fungal pathogenicity and soybean host resistance to frogeye leaf spot (FLS), which is caused by C. sojina. …

Development Of Near-Isogenic Lines In A Parthenogenetically Reproduced Thrips Species, Frankliniella Occidentalis, Guangdi Yuan, Yanran Wan, Xiaoyu Li, Bingqing He, Youjun Zhang, Baoyun Xu, Shaoli Wang, Wen Xie, Xuguo Zhou, Qingjun Wu

Entomology Faculty Publications

Although near-isogenic lines (NILs) can standardize genetic backgrounds among individuals, it has never been applied in parthenogenetically reproduced animals. Here, through multiple rounds of backcrossing and spinosad screening, we generated spinosad resistant NILs in the western flower thrips, Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), with a haplo-diploid reproduction system. The resultant F. occidentalis NIL-R strain maintained a resistance ratio over 30,000-fold, which was comparable to its parental resistant strain, Spin-R. More importantly, F. occidentalis NIL-R shared 98.90% genetic similarity with its susceptible parental strain Ivf03. By developing this toolset, we are able to segregate individual resistance and facilitate the mechanistic study …

The Soy-Derived Peptide Lunasin Inhibits Invasive Potential Of Melanoma Initiating Cells, Chris Shidal, Jun-Ichi Inaba, Kavitha Yaddanapudi, Keith R. Davis

Plant Pathology Faculty Publications

Lunasin is a 44 amino acid peptide with multiple functional domains including an aspartic acid tail, an RGD domain, and a chromatin-binding helical domain. We recently showed that Lunasin induced a phenotype switch of cancer initiating cells (CIC) out of the stem compartment by inducing melanocyte-associated differentiation markers while simultaneously reducing stem-cell-associated transcription factors. In the present study, we advance the hypothesis that Lunasin can reduce pools of melanoma cells with stem cell-like properties, and demonstrate that Lunasin treatment effectively inhibits the invasive potential of CICs in vitro as well as in vivo in a mouse experimental metastasis model. Mice …

Development Of Molecular Tools For Identification Of Prairie Terrestrial And Wetland Algae, Esther Mundembo Kapinga

UNO Student Research and Creative Activity Fair

Algae are a diverse group of photosynthetic protists. Green algae are typically unicellular, though some may occur as multicellular colonies, and they are found across a wide range of habitats, including marine, freshwater, and terrestrial environments. As photosynthetic producers and sometimes symbionts, algae can occupy important roles in an ecosystem; in other circumstances they can have negative impacts on environmental quality. Estimations of the number of green algal species range from eight thousand to over fifteen thousand. The identification of individual algal species can be problematic due to their small size and typically simple cell anatomy. For this reason, molecular …

Small Scale Heterogeneity In Vegetation Structure In A Patch-Burn-Grazing Landscape, Eric G. Behrens

UNO Student Research and Creative Activity Fair

Disturbances are drivers of spatial change in the plant communities of the tallgrass prairie ecosystem. Fire and large herbivore grazing are prevalent disturbances that maintain the vegetation structure and create spatial heterogeneity in vegetation at various scales. The fire-grazing disturbance interaction occurs when areas that have been recently burned are followed by intense grazing due to the high quality of forage regrowth. This interaction has been managed in tallgrass prairies in a homogenous method using uniform burning and grazing and a heterogeneous method using patch-burn-grazing (PBG). Vegetation heterogeneity at a large scale has been studied in PBG and uniformly managed …

Competition From Bromus Tectorum Removes Differences Between Perennial Grasses In N Capture And Conservation Strategies, Rebecca E. Drenovsky, Jeffrey T. Walker, J. J. James

Biology

Background and aims

Competition from the annual grass Bromus tectorum threatens aridland perennial bunchgrass communities. Unlike annuals, perennials must allocate part of their first year nitrogen (N) budget to storage rather than growth, potentially placing them at a competitive disadvantage.

Methods

We evaluated N acquisition and conservation for two perennial bunchgrasses, Agropyron desertorum and Pseudoroegneria spicata, at the seedling stage to investigate potential trade-offs between storage and growth when grown with and without B. tectorum under two levels of soil N.

Results

Agropyron desertorum had higher growth rates, N uptake, and N productivity than P. spicata when grown without …

Proceedings Of The 44th Annual Meeting, Southern Soybean Disease Workers (March 8-9, 2017, Pensacola Beach, Florida), Terry Spurlock, Trey Price, Heather M. Kelly, Danise Beadle, Patricia Bollich, Tom Allen

Southern Soybean Disease Workers: Conference Proceedings

Contents

Agenda for March 8-9, 2017

Contributed papers

Soybean cyst nematode: current status, challenges and opportunities. G Tylka and K Bissonnette

Updates of the 2nd SCN (Soybean Cyst Nematode) Coalition. Albert Tenuta

Developing management zones for nematodes in soybean. C Overstreet, EC McGawley, DM Xavier-Mis, and M Kularathna

Microbial communities associated with long-term tillage and fertilizer management practices. AY Srour, J Hackman, RL Cook, JP Bond, and AM Fakhoury

Microbial profile of SDS-suppressive soils in soybean fields. AY Srour, LFS Leonardo, DK Malvick, JP Bond, and AM Fakhoury

Understanding the phytobiome; using strip trials and spatial analysis to determine concomitant …

Biomass Yield Of Switchgrass Cultivars Under High- Versus Low-Input Conditions, Michael D. Casler, Sergio Sosa, Lindsey Hoffman, Hilary Mayton, Calvin Ernst, Paul R. Adler, Arvid R. Boe, Stacy A. Bonos

Agronomy, Horticulture and Plant Science Faculty Publications

Switchgrass (Panicum virgatum L.) is undergoing development as a biomass crop to support conversion of cellulosic biomass to energy. To avoid the competition of biomass with food or feed crops, most commercialization proposals suggest that switchgrass should be grown exclusively on marginal lands that are not fit for food or feed production. The objective of this study was to investigate the potential for cultivar x environment interactions that would affect the methods and approaches for breeding and evaluating switchgrass cultivars, including both upland and lowland types, for high-input versus low-input types of environments. Biomass yield was measured on 14 cultivars …

The Lx Report Of The Bean Improvement Cooperative No. 60, March 2017.

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

CONTENTS

LX Annual Report of the Bean Improvement Cooperative xi

BIC Coordinating Committee Membership - 1957 to 2017 . xii

BIC Meritorious Service and Distinguished Achievement Award Recipients - 1957 to 2015 xiii

BIC Awards Nomination Request for 2017 xvi

BIC/NAPIA Meeting in 2017 . xix

In Memory of Guillermo E. Galvez-Enriquez xx

RESEARCH PAPERS FOR 2017

OPTIMIZING SPORULATION OF Pseudocercospora griseola IN VITRO • Paula F. de Pádua1, Rafael Pereira1, Luanna B. W. Gomes1 and Elaine A. de Souza1* 1

FINE MAPPING THE BROAD SPECTRUM ANTHRACNOSE RESISTANCE GENE IN AMENDOIM CAVALO 3 • Gilio, T.A.S.1, Oscar P. Hurtado-Gonzales2, Giseli …

Psychoactive Plants: A Bibliography, James P. Smith Jr

Botanical Studies

No abstract provided.

Grass Floras, Manuals, And Checklist, James P. Smith Jr

Botanical Studies

No abstract provided.