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Overcoming Anthropogenic Impediments Of Reintroduced Bighorn Sheep Populations In North-Central Utah, Loren Chase

Journal of Undergraduate Research

Bighorn sheep (Ovis canadensis) were historically abundant in many places in Utah, however, when the area was settled, humans brought with them many causes for bighorn extermination. Unregulated hunting, competition for resources by livestock, reduced water availability, reduce range quantity, home range encroachment, and the lungworm/pneumonia complex are all major reasons as to why the bighorns are threatened in the western states (Enk 2001, Karpowitz and Stewart 2000, Smith et al. 1988, Smith and Flinders 1992). The first two problems were handled at the socio-political level, by managing people rather than wildlife. However water scarcity persists, urban sprawl continues to …

Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen

Biological Sciences Faculty Research

Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over an interval of …

Incorporating Satellite Derived Cloud Climatologies To Improve High Resolution Interpolation Of Daily Precipitation., Adam M. Wilson, Benoit Parmentier, Brian Mcgill, Rob Guralnick, Walter Jetz

Yale Day of Data

Conservation of biodiversity demands comprehension of evolutionary and ecological patterns and processes that occur over vast spatial and temporal scales. A central goal of ecology is to understand the factors that control the spatial distribution of species and this has become even more important in the face of climate change. However, at global scales there can be enormous uncertainty in environmental data used to model species distributions. Even ‘simple’ metrics such as mean annual precipitation are difficult to estimate in areas with few weather stations and available data sets do not quantify uncertainty in these surfaces. We are developing a …

A Study Of The Historical Development And Horticultural Practices Of A Public Garden, Steven J. Nosal

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

This project examined the historical development and the horticultural practices in the public gardens of the Parks Department in Lincoln, Neb. It concentrates on one particular place to illustrate development and practice issues: the Sunken Gardens. This garden was built during the Depression in the 1930s as a place of beauty for all of the citizens of Lincoln. Although the Sunken Garden covers only 1.5 acres, it has remained a very important part of Nebraska's capital city for more than 64 years.

The Effects Of Planting Techniques On Maize Grain Yield And Silage Production, Tyler D. Kaufman

Theses and Dissertations

This thesis is a comprehensive analysis of the effects of seed orientation, row direction and planting population on grain yield, kernel composition, and silage yield and composition. Producers are striving to increase profit by efficiently using their available land area to maximize crop production. However, little research is available testing the effect of seed orientation on grain or silage production. Quantifying the impacts of seed orientation and row direction on grain and silage is essential for maximum crop production. Dissemination of the results should benefit grain and silage producer.

Two experiments were conducted to evaluate the effects of manipulating seed …

Characterization Of A Cdna Encoding Β-Amyrin Synthase Involved In Saponin Biosyntheses In Chenopodium Quinoa, Derrick J. Reynolds, Dr. P. Jeff Maughan

Journal of Undergraduate Research

Quinoa (Chenopodium quinoa Willd) is an important crop for subsistence farmers in the Altiplano (high plains) of Peru, Bolivia, and Argentina. Quinoa has the potential to be an effective crop for many temperate and highland-tropical regions due to its ability to thrive in drought, saline and high-altitude conditions. The nutritional value of quinoa has been well documented. Several analyses have confirmed that quinoa grain has an excellent balance of carbohydrates, lipids, and proteins and provides an ideal balance of essential amino acids for human nutrition.1 Quinoa grain also has a seed coating consisting of various saponins. Saponins are waxy, soap-like …

Enantioselective Synthesis Of Biologically Important Compounds, David G. Evans, Dr. Matt A. Peterson

Journal of Undergraduate Research

Until only very recently it has been the common practice of most pharmaceutical manufacturers and manufacturers of agrochemicals such as herbicides and insecticides to market chiral compounds as mixtures of enantiomers. This practice has been driven by market forces due to the fact that it is much more cost efficient to market chiral compounds as mixtures rather than invest the resources needed to separate them. Tragic cases have shown that there is indeed a need for complete separation of enantiomers and their separate pre-clinical and clinical evaluation.

Title, Scott A. Davis, Dr. Bruce Roundy

Journal of Undergraduate Research

The invasion of non-native species, mainly cheatgrass (Bromus tectorum), into our rangelands, especially following the destruction caused by wildfires, has made it necessary to find viable options for the restoration of native plant species to these areas. The aim of this project was to determine whether or not it is possible to create models for the germination and seminal root growth of a suite of species using heat accumulation models. By creating these models, we hope to be able to discover other native species that not only compete with cheatgrass through early establishment, but provide a quality food source for …

Bioavailable Lead In Topsoil Collected From General Aviation Airports, Jerry H. Kavouras, Randal J. Demik, Allison C. Hopkins

Biology Department Faculty Articles

Representatives of the aviation community are interested in determining the environmental effects of leaded fuel emissions from general aviation flight operations. Soil is an environmental sink for lead to accumulate over time. This study measured bioavailable lead concentrations in topsoil at three general aviation airports and at one site with no general aviation operations in order to determine if general aviation aircraft operations are contributing to the contamination of airport topsoil at levels that require remediation by law. Bioavailable refers to substances that organisms can absorb, because they have access to them. Topsoil was collected from refueling areas, run-up areas, …

Economic Impact Assessment Of Sorghum, Millet And Other Grains Crsp: Sorghum And Millet Germplasm Development Research, Timothy J. Dalton, Yacob A. Zereyesus

INTSORMIL Scientific Publications

As a result of the offsetting effect of a rise in productivity and decline in harvested area, the world sorghum production (tonnes) has been on a horizontal trend. The combined effect of a decline in area harvested and a rise in yield productivity have resulted in an overall increase in world millet production (tonnes) trend.

During the last three decades, significant numbers of breeding lines, parental stocks, germplasm and cultivars have been released through INTSORMIL/host countries collaboration around the world. Some of the remarkable breeding success stories include the release of the first hybrid sorghum Hageen Dura (HD-1) and Striga …

Tall Fescue Endophyte Effects On Tolerance To Water-Deficit Stress, Padmaja Nagabhyru, Randy D. Dinkins, Constance L. Wood, Charles W. Bacon, Christopher L. Schardl

Plant Pathology Faculty Publications

BACKGROUND: The endophytic fungus, Neotyphodium coenophialum, can enhance drought tolerance of its host grass, tall fescue. To investigate endophyte effects on plant responses to acute water deficit stress, we did comprehensive profiling of plant metabolite levels in both shoot and root tissues of genetically identical clone pairs of tall fescue with endophyte (E+) and without endophyte (E-) in response to direct water deficit stress. The E- clones were generated by treating E+ plants with fungicide and selectively propagating single tillers. In time course studies on the E+ and E- clones, water was withheld from 0 to 5 days, during which …

Biology And Control Of Common Purslane (Portulaca Oleracea L.), Christopher A. Proctor

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

Common purslane (Portulaca oleracea L.) is a summer annual with wide geographic and environmental distribution. Purslane is typically regarded as a weed in North America, but it is consumed as a vegetable in many parts of the world. One of the characteristics that make purslane difficult to control as a weed is its ability to vegetatively reproduce. Severed sections of purslane stem containing a node will produce adventitious roots from the cut end of the stem. Isoxaben and simazine were the only two effective preemergence herbicides for controlling purslane in our studies when applied at maximum or one-half maximum …

Confirming Artificial Fungal Endophyte Inoculation Of Maize By Aflp And Sem, Alan Chambers, Dr. Brad Geary

Journal of Undergraduate Research

Plant microbe interactions have been shown to enhance plant growth (Nassar, 2005) and it is well established that fungal endophytes affect beneficial phenotypes like resistance to drought or insects (Bacon 1997). Plants have been selected for beneficial phenotypic traits for thousands of years, but selection for beneficial microbe interactions is under studied. We desire to investigate improving crop yield and quality, while minimizing the expenditure of natural resources, by growing maize artificially infected with fungal endophytes from plants adapted to stressful environments. We report our early success here.

Transformations In Matter And Energy: Student Learning And Inquiry To Inform Teaching, Jenny Dauer

Discipline-Based Education Research Group Speaker Series

Learning progressions are descriptions of increasing levels of sophistication of student reasoning about a topic based on empirical evidence. Our learning progression framework about student explanations of carbon-transforming processes (e.g. photosynthesis, cellular respiration) describes how student’s interconnected and mutually supporting ideas and practices are deeply embedded in discourse at all levels of achievement. My research is in two areas: 1) applying the learning progression framework for student explanations of carbon-transforming processes to describe the most productive pathways for student learning, 2) extending the research to student reasoning during inquiry activities about carbon-transforming processes. One finding is that students who consistently …

Scale-Sensitive Linear Analysis Of Granivorous Rodent Population Dynamics, Nikkala A. Pack, Dr. Brian A. Maurer

Journal of Undergraduate Research

Ecological systems undergo perturbations; populations grow, decline, or go extinct. If the effect of one population on another can be determined, when one population is perturbed, we can predict the response of the second population. This is important for conservation efforts, for example, in predicting the effects of species removal by forest fire.

Isolation Of Molecular Markers Linked To Sw-5 Using Genetically Directed Representational Difference Analysis (Gdrda), Rachel E. Raphael, Dr. Mikel R. Stevens

Journal of Undergraduate Research

Tospoviruses, including tomato spotted wilt virus (TSWV), infect over 550 plant species worldwide. In the commercially grown tomato (Lycopersicon 1 esculentum) TSWV decreases fruit yields and quality in up to 80-90% of the crop in South Africa2 with similar losses in Hawaii3 and other areas around the world.

Metagenomic Profiling Reveals Lignocellulose Degrading System In A Microbial Community Associated With A Wood-Feeding Beetle, Erin D. Scully, Scott M. Geib, Kelli Hoover, Ming Tien, Susannah G. Tringe, Kerrie W. Barry, Tijana Glavina Del Rio, Mansi Chovatia, Joshua R. Herr, John E. Carlson

Department of Plant Pathology: Faculty Publications

The Asian longhorned beetle (Anoplophora glabripennis) is an invasive, wood-boring pest that thrives in the heartwood of deciduous tree species. A large impediment faced by A. glabripennis as it feeds on woody tissue is lignin, a highly recalcitrant biopolymer that reduces access to sugars and other nutrients locked in cellulose and hemicellulose. We previously demonstrated that lignin, cellulose, and hemicellulose are actively deconstructed in the beetle gut and that the gut harbors an assemblage of microbes hypothesized to make significant contributions to these processes. While lignin degrading mechanisms have been well characterized in pure cultures of white rot basidiomycetes, little …

Identification Of Proteins For Salt Tolerance Using A Comparative Proteomics Analysis Of Tomato Accessions With Contrasting Salt Tolerance, Peter Nveawiah-Yoho, Jing Zhou, Marsha Palmer, Roger Sauve, Suping Zhou, Kevin J. Howe, Tara Fish, Theodore W. Thannhauser

Agricultural and Environmental Sciences Faculty Research

Tomato (Solanum lycopersicum) has a wide variety of genotypes differing in their responses to salinity. This study was performed to identify salt-induced changes in proteomes that are distinguishable among tomatoes with contrasting salt tolerance. Tomato accessions [LA4133 (a salt-tolerant cherry tomato accession) and ‘Walter’ LA3465 (a salt-susceptible accession)] were subjected to salt treatment (200 mm NaCl) in hydroponic culture. Salt-induced changes in the root proteomes of each tomato accession were identified using the isobaric tags for relative and absolute quantitation (iTRAQ) method. In LA4133, 178 proteins showed significant differences between salt-treated and non-treated control root tissues (P ≤ 0.05); 169 …

Seed Burial Physical Environment Explains Departures From Regional Hydrothermal Model Of Giant Ragweed (Ambrosia Trifida) Seedling Emergence In U.S. Midwest, Adam S. Davis, Sharon Clay, John Cardina, Frank Forcella, John Lundquist, Christy Sprague

Agronomy, Horticulture and Plant Science Faculty Publications

Robust predictions of weed seedling emergence from the soil seedbank are needed to aid weed management. A common seed accession (Illinois) of giant ragweed was buried in replicate experimental gardens over 18 site years in Illinois, Michigan, Kansas, Nebraska, Ohio, and South Dakota to examine the importance of site and climate variability by year on seedling emergence. In a nonlinear mixed-effects modeling approach, we used a flexible sigmoidal function (Weibull) to model giant ragweed cumulative seedling emergence in relation to hydrothermal time accumulated in each site-year. An iterative search method across a range of base temperature (Tb ) and base …

Dynamic Expression Of Imprinted Genes Associates With Maternally Controlled Nutrient Allocation During Maize Endosperm Development, Mingming Xin, Ruolin Yang, Guosheng Li, Hao Chen, John Laurie, Chuang Ma, Dongfang Wang, Yingyin Yao, Brian A. Larkins, Qixin Sun, Ramin Yadegari, Xiangfeng Wang, Zhongfu Ni

Center for Plant Science Innovation: Faculty Publications

In angiosperms, the endosperm provides nutrients for embryogenesis and seed germination and is the primary tissue where gene imprinting occurs. To identify the imprintome of early developing maize (Zea mays) endosperm, we performed highthroughput transcriptome sequencing of whole kernels at 0, 3, and 5 d after pollination (DAP) and endosperms at 7, 10, and 15 DAP, using B73 byMo17reciprocal crosses.Weobserved gradually increased expression of paternal transcripts in 3- and 5-DAP kernels. In 7-DAP endosperm, the majority of the genes tested reached a 2:1 maternal versus paternal ratio, suggesting that paternal genes are nearly fully activated by 7 DAP. …

Report Card On Sustainable Natural Resource Use In Agriculture, Robert Summers, David Weaver

All other publications

Condition and trend Nutrients, such as phosphorus (P), are essential for profitable agriculture in the south-west of WA; however, excess P – more than is required for optimal production – is stored in many agricultural soils. On average, pasture soils and arable soils contain 1.3 times and 1.6 times respectively, as much P as is required for optimal production. Production in P-enriched soils is more likely to be constrained by soil acidity (50–60% of pasture and arable soils), potassium (K) (50% of pasture soils and less than 10% of arable soils), and sulphur (S) (30% of pasture soils). Management implications …

Nebline, September 2013

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: Community Gardens are Growing: UNL Extension in Involved With Several in Lincoln

Farm Views

Urban Agriculture

Food & Fitness

Home & Family Living

Horticulture

Environmental Focus

4-H & Youth

Community Focus

Extension Calendar

Nutrition Education Program

Family and Community Education (FCE) Clubs

and other extension news and events

Cryptic Genetic Subdivision In The San Benito Evening Primrose (Camissonia Benitensis), Cynthia A. Dick, Julie A. Herman, Ryan E. O'Dell, Adriana Lopez-Villalobos, Chris Eckert, Justen B. Whittall

Biology

When rare plants are distributed across a range of habitats, ecotypic differentiation may arise requiring customized conservation measures. The rate of local adaptation may be accelerated in complex landscapes with numerous physical barriers to gene flow. In such cases, examining the distribution of genetic diversity is essential in determining conservation management units. We investigated the distribution of genetic diversity in the federally threatened Camissonia benitensis (Onagraceae), which grows in two distinct serpentine habitats across several watersheds in San Benito, Fresno, and Monterey Cos., CA, USA. We compared genetic diversity with that of its two widespread relatives, C. contorta and C. …

Summaries Of Arkansas Cotton Research 2012, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Climate Change And North American Rangelands: Assessment Of Mitigation And Adaptation Strategies, Linda A. Joyce, David D. Briske, Joel R. Brown, H. Wayne Polley, Bruce A. Mccarl, Derek W. Bailey

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Recent climatic trends and climate model projections indicate that climate change will modify rangeland ecosystem functions and the services and livelihoods that they provision. Recent history has demonstrated that climatic variability has a strong influence on both ecological and social components of rangeland systems and that these systems possess substantial capacity to adapt to climatic variability. Specific objectives of this synthesis are to: 1) evaluate options to mitigate greenhouse gas emissions and future climate change; 2) survey actions that individuals, enterprises, and social organizations can use to adapt to climate change; and 3) assess options for system transformation when adaptation …

Real-Time Quantitative Pcr Assays For Evaluation Of Soybean Varieties For Resistance To The Stem And Root Rot Pathogen Phytophthora Sojae, Mursel Catal, Fedai Erler, Dennis W. Fullbright, Gerard C. Adams

Department of Plant Pathology: Faculty Publications

Phytophthora root and stem rot caused by Phytophthora sojae is one of the most destructive disease of soybeans in the world. Effective management of the disease depends on selection and use of soybean varieties resistant to the disease. Fast and reliable procedures are vital to screen soybean varieties against the pathogen. Novel real-time quantitative (qPCR) assays were developed for both absolute and relative quantification of P. sojae in infected root tissues. QPCR assays were based on the detection of the internal transcribed spacer (ITS) gene of the pathogen and 18S ribosomal gene of the host plant. Absolute qPCR allowed the …

Epilithic And Aerophilic Diatoms In The Artificial Environment Of Kungsträdgården Metro Station, Stockholm, Sweden, Lena Norbäck Ivarsson, Magnus Ivarsson, Johannes Lundberg, Therese Sallstedt, Catarina Rydin

International Journal of Speleology

The Kungsträdgården metro station is an artificial and urban subsurface environment illuminated with artificial light. Its ecosystem is almost completely unknown and as a first step to better understand the biology and rock wall habitats the diatom flora was investigated. A total of 12 species were found growing on the rock walls of Kungsträdgården metro station. The results show the diatom flora in Kungsträdgården to be dominated by e.g. Diadesmis contenta, Diadesmis perpusilla, Pinnularia appendiculata, Nitzschia amphibia, Nitzschia sinuata and Diploneis ovalis. One species, Caloneis cf. aerophila, has never been reported from Sweden before. …

Genetic Diversity Of Native Utah Flora, Benjamin Brulotte, Dr. Mikel Stevens

Journal of Undergraduate Research

Amplified fragment length polymorphisms are a reliable, straightforward method of determining the genetic diversity of species. Frequently this method of determining genetic diversity has been used in conservation efforts because of its cost effectiveness, and efficiency. We set out to characterize the genetic diversity of three native species of wildflower common in the Intermountain West, and frequently used in Forest Service revegetation projects.

Mscs-Like Mechanosensitive Channels In Plants And Microbes, Margaret E. Wilson, Grigory Maksaev, Elizabeth S. Haswell

Biology Faculty Research

The challenge of osmotic stress is something all living organisms must face as a result of environmental dynamics. Over the past three decades, innovative research and cooperation across disciplines have irrefutably established that cells utilize mechanically gated ion channels to release osmolytes and prevent cell lysis during hypoosmotic stress. Early electrophysiological analysis of the inner membrane of Escherichia coli identified the presence of three distinct mechanosensitive activities. The subsequent discoveries of the genes responsible for two of these activities, the mechanosensitive channels of large (MscL) and small (MscS) conductance, led to the identification of two diverse families of mechanosensitive channels. …

Subset Of Heat-Shock Transcription Factors Required For The Early Response Of Arabidopsis To Excess Light, Hou-Sung Jung, Peter A. Crisp, Gonzalo M. Estavillo, Benjamin Cole

Dartmouth Scholarship

Sunlight provides energy for photosynthesis and is essential for nearly all life on earth. However, too much or too little light or rapidly fluctuating light conditions cause stress to plants. Rapid changes in the amount of light are perceived as a change in the reduced/oxidized (redox) state of photosynthetic electron transport components in chloroplasts. However, how this generates a signal that is relayed to changes in nuclear gene expression is not well understood. We modified redox state in the reference plant, Arabidopsis thaliana, using either excess light or low light plus the herbicide DBMIB (2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone), a well-known inhibitor of photosynthetic …