Digital Commons Network^™

Folate Synthesis In Plants: The First Step Of The Pterin Branch Is Mediated By A Unique Bimodular Gtp Cyclohydrolase I, Gilles J. C. Basset, Eoin P. Quinlivan, Michael J. Ziemak, Rocío Díaz De La Garza, Markus Fischer, Susi Schiffmann, Adelbert Bacher, Jesse F. Gergory Iii, Andrew D. Hanson

Center for Plant Science Innovation: Faculty Publications

GTP cyclohydrolase I (GCHI) mediates the first and committing step of the pterin branch of the folate-synthesis pathway. In microorganisms and mammals, GCHI is a homodecamer of ≈26-kDa subunits. Genomic approaches identified tomato and Arabidopsis cDNAs specifying ≈50-kDa proteins containing two GCHI-like domains in tandem and indicated that such bimodular proteins occur in other plants. Neither domain of these proteins has a full set of the residues involved in substrate binding and catalysis in other GCHIs. The tomato and Arabidopsis cDNAs nevertheless encode functional enzymes, as shown by complementation of a yeast fol2 mutant and by assaying GCHI activity …

Isolation And Characterization Of A Virus That Infects Emiliania Huxleyi (Haptophyta), Tonje Castberg, Runar Thyrhaug, Aud Larsen, Ruth-Anne Sandaa, Mikal Heldal, James L. Van Etten, Gunnar Bratbak

Department of Plant Pathology: Faculty Publications

The isolation and characterization of a virus (designated EhV) that infects the marine coccolithophorid Emiliania huxleyi (Lohmann) Hay & Mohler are described. Three independent clones of EhV were isolated from Norwegian coastal waters in years 1999 and 2000. EhV is a double-stranded DNA-containing virus with a genome size of ~415 kilo-base pairs. The viral particle is an icosahedron with a diameter of 160–180 nm. The virus particle contains at least nine proteins ranging from 10 to 140 kDa; the major capsid protein weighs ~54 kDa. EhV has a latent period of 12–14 h and a burst size of 400–1,000 (mean, …

Crop Production On The Lunar Surface Using Solar Fiber Optics: Mitigating The Effects Of Prolonged Darkness With Low Temperature And Low Light, Bruce Bugbee, Julie K. Chard

NASA

Plant metabolism and growth are reduced in low temperature. As metabolism slows, energy requirements are reduced and less light is needed. The temperature should be maintained above the chilling temperature for the plant, which is species dependent. The addition of light will allow the plant to continue to expend energy on maintenance and some growth. Here we show that low light and cool temperatures can be used to maintain plants through the 14.7 days on the dark side of the Moon. Growth resumes immediately after the light is restored.

Native Plants: The Preservation And Restoration Of Native Plants In Designed Landscapes In Northwest Arkansas, Janet Coleman

Inquiry: The University of Arkansas Undergraduate Research Journal

A decline in Northwest Arkansas's native plant population has occurred over the past 50 years, as documented by the U.S. Forest Service in the Ozark-Ouachita Highlands Assessment. This decline has been caused by increased human development in natural areas and the replacement of native plants with exotic, non-native plants. As a result, a generation has grown up not knowing what an Ozark wake Robin trillium (Trillium pusillum var. ozarkanum) or Blood root (Sanguinaria canadensis) Look like, because these plants are difficult to find in nature, are not commonly grown in designed landscapes, and are Largely unavailable in garden centers. The …

Characterization Of Wound-Inducible Genes Encoding Enzymes For Terpenoid Biosynthesis In Medicago Truncatula, Mandy M. Cox

Inquiry: The University of Arkansas Undergraduate Research Journal

In addition to having numerous applications as food flavorings and pharmaceuticals, terpenoids are an important class of defensive compounds that can accumulate in plants after pathogen infection or injury by insects. Sequences of DNA encoding putative terpene synthases and an oxidosqualene synthase, isolated from insect-damaged Medicago truncatula leaves, were selected from an expressed sequence tag (EST) database. The eDNA clones were used as radiolabeled probes to analyze gene expression in leaves treated with factors known to trigger a defense response in plants. Transcript levels for all of the genes examined increased in response to artificial wounding, insect herbivory, and methyl …

Failure Analysis: Crop Production On The Lunar Surface, Julie K. Chard, Giridhar Akula, Bruce Bugbee

NASA

We have sought to optimize conditions for crop yield for many years, but optimal conditions will not always be cost effective. More importantly, environmental control systems routinely fail, and we need to learn how to gracefully recover from these failures.

Failures of the power supply system are among the most common and most detrimental of all system failures. A battery back-up could supply a small amount of power during a power outage, but we need to know how to best utilize the back-up power.

Early in this project, it became clear that the detrimental effects of a power loss could …

Effects Of Management Practices On Grassland Birds: Horned Lark, Meghan F. Dinkins, Amy L. Zimmerman, Jill A. Dechant, Barry D. Parkin, Douglas H. Johnson, Lawrence D. Igl, Christopher M. Goldade, Betty R. Euliss

United States Geological Survey: Effects of Management Practices on Grassland Birds

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which …

Giving Baculoviruses A Better Edge, Arthur H. Mcintosh, Cynthia L. Goodman, James J. Grasela, Ben Hardin

Agricultural Research Magazine

Scientific advancements built on an understanding of what nature already provides are leading to environmentally friendly crop-pest control by either biological agents or specifically designed synthetic antiinsect compounds. A case in point: research on baculoviruses.

Baculoviruses are rod-shaped DNA viruses, many of which begin their life cycle reproducing inside cells. In the nuclei of caterpillar cells infected with baculoviruses, viral progeny multiply and are incorporated into protective polyhedronshaped protein structures called occlusion bodies. Infected caterpillars die and contaminate the leaf surfaces with the occlusion bodies. Then, healthy caterpillars ingest the occlusion bodies and release the virus when feeding on contaminated …

Manure Matters, Volume 8, Number 1, Bahman Eghball, John Gilley

Manure Matters (newsletter)

Phosphorus Risk Assessment Index Evaluation Using Runoff Measurements

Published by University of Nebraska – Lincoln’s Livestock Environmental Issues Committee. Manure and composted manure are valuable and renewable resources that can be effectively utilized for crop production and soil improvement. However, runoff from cropland areas receiving manure or compost may contribute to increased phosphorus (P) in streams and lakes. The main factors controlling P movement in surface runoff are transport (runoff and erosion) and source factors such as manure or fertilizer application method and rate, and soil P test level. Elevated soil P levels may result from application of manure at …

Manure Matters, Volume 8, Number 3, Charles S. Wortmann

Manure Matters (newsletter)

How much can you pay to have manure applied to your land?

Livestock feeders often need more land for manure application to avoid excessive buildup of soil phosphorus. In some cases, they request payment to reduce transport costs. When is manure a good buy for crop production?
Manure supplies the full complement of nutrients needed by crops and often helps to improve soil biological and physical properties such as the rate of water infiltration. Because of these soil improvements, crop yield is often more with manure application than with fertilizers.
One way of estimating the value of manure is to …

Manure Matters, Volume 8, Number 2, Christopher G. Henry, Dennis D. Schulte

Manure Matters (newsletter)

Assessing Odor Risk

Odors from animal production operations are a major concern in rural communities. Pressure from the public and the potential impact on the rural economy has caused strong emotional conflicts. Currently livestock producers and urban planning officials have few tools to objectively evaluate scientifically based setbacks between livestock operations and residential areas. Conversely, livestock producers have few tools available to them to demonstrate how odor control technologies can reduce the risk potential of odor incidents.

Recognizing this concern in Minnesota, the Minnesota Legislature provided funds to their University to develop a tool to help predict offsite odor movement …

Manure Matters, Volume 8, Number 8, Richard R. Stowell, Christopher G. Henry

Manure Matters (newsletter)

The Economic Potential of Methane Recovery for Swine Operations: Projected Impacts of Various Public-Policy Scenarios

Economic analyses were performed on anaerobic digestion of manure from finishing operations. The main factors considered were herd size (1,000 head; 3,500 head; and 10,000 head) and method of financial support provided (cost-share program, no-interest loans, tax subsidies, and subsidized electrical sales).
Installation of a digester system is a significant investment that is currently very difficult to justify economically to Nebraska producers based upon consideration of readily quantifiable income and expenses, regardless of farm size. Swine finishing operations looking to invest in this technology would …

Nebline, January 2002

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Salt Valley Clean Lakes Project Benefits Area Lakes
Wood For Your Fireplace
Recognizing Living, Hazardous Trees
Needle Diseases of Conifers
New Arsenic Standards Won’t Affect Lancaster Public Water Supplies
Beginning Beekeeping Workshop
Considering Ultrasonic Pest Control Devices? Save Your Money
Keeping Backyard Birds Safe
Check Condition of Stored Grain
Fertilizing Crop Land With Biosolids
Testing Feed and Balancing Rations Saves Money
Farm Management Web Page Added
“Care and Feeding” of Your Septic Tank
Frozen Pipes
Prevent Home Fires
One Diet You Just Can’t Fail
Eating Healthy: Enjoy Nebraska Foods
Seniors Rewarded with Feast
Clean Hands Campaign
Clarice’s Column
Household Hints …

Review And Interpretation: Nitrogen Management Strategies To Reduce Nitrate Leaching In Tile-Drained Midwestern Soils, Dana L. Dinnes, Douglas L. Karlen, Dan B. Jaynes, Thomas C. Kaspar, Jerry L. Hatfield, Thomas S. Colvin, Cynthia A. Cambardella

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

Balancing the amount of N needed for optimum plant growth while minimizing the NO₃ that is transported to ground and surface waters remains a major challenge for everyone attempting to understand and improve agricultural nutrient use efficiency. Our objectives for this review are to examine how changes in agricultural management practices during the past century have affected N in Midwestern soils and to identify the types of research and management practices needed to reduce the potential for nonpoint NO₃ leakage into water resources. Inherent soil characteristics and management practices contributing to nonpoint NO₃ loss from Midwestern soils, …

Response Of Lowland Rice Plants To Simulated Insect Defoliation In West Africa, I. O. Oyediran, E. A. Heinrichs

Department of Entomology: Faculty Publications

Field experiments were conducted to investigate the impact of simulated insect-caused defoliation on irrigated rice. Defoliation levels tested were 0% (control), 25% defoliation at 21 days after transplanting (dat), 25% defoliation at 41 dat, 25% defoliation at 21 and 42 dat, 50% defoliation at 21 dat, 50% defoliation at 42 dat, 75% defoliation at 21 dat, 75% defoliation at 42 dat, 75% defoliation at 21 and 42 dat, 100% defoliation at 21 dat, and 100% defoliation at 21 and 42 dat. Tiller height, total number of tillers, percent panicle-bearing tillers, weight of 100 grains, and grain yields were recorded. The …

The Fringing Halophytic Vegetation Of Lake Austin: A Study Of Mining Impacts And Vegetation Dynamics, Simone Vellekoop

Theses : Honours

Mining operations in arid regions of Western Australia are faced with many environmental management issues. One such issue is the disposal of mine water to the environment. Mine water is commonly discharged to nearby salt lakes under licence by the Department of Environmental Protection. Licence conditions dictate that the discharge water and the receiving environment be monitored to allow impacts on the environment to be detected. Salt lakes are associated with vegetation communities dominated by halophytic members of the Chenopodiaceae, While these plants are tolerant of salinity extremes, the germination stage of many species requires periods of lowered salinity. There …

Stomatal Responses Of Douglas-Fir Seedlings To Elevated Carbon Dioxide And Temperature During The Third And Fourth Years Of Exposure, James D. Lewis, Melissa S. Lucash, David M. Olszyk, David T. Tingey

Environmental Science and Management Faculty Publications and Presentations

Two major components of climate change, increasing atmospheric [CO₂] and increasing temperature, may substantially alter the effects of water availability to plants through effects on the rate of water loss from leaves. We examined the interactive effects of elevated [CO₂] and temperature on seasonal patterns of stomatal conductance (g_s), transpiration (E) and instantaneous transpiration efficiency (ITE) in Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. Seedlings were grown in sunlit chambers at either ambient CO₂ (AC) or ambient + 180 µmol mol^-1 CO₂ (EC), and at ambient temperature (AT) or ambient + 3.5° …

Endophyte Ergot Alkaloid Synthetic Compounds, Compounds Which Encode Therefor And Related Methods, Christopher L. Schardl, Jinhung Wang

Plant Pathology Faculty Patents

The present invention provides, inter alia, dmaW nucleic acid sequences and the proteins for which they encode. Also provided are methods for the utilization of knockout mutants of the sequences which are useful for engineering ergot alkaloid-deficient fungal symbionts (endophytes) of plants. Other methods and materials related to these sequences are also provided.

Compensation For Herbivory In Wild Sunflower: Response To Simulated Damage By The Head-Clipping Weevil, Diana Pilson, Karin L. Decker

Diana Pilson Publications

Herbivore damage is generally detrimental to plant fitness, and the evolutionary response of plant populations to damage can involve either increased resistance or increased tolerance. While characters that contribute to resistance, such as secondary chemicals and trichomes, are relatively well understood, characters that contribute to a plant’s ability to tolerate damage have received much less attention. Using Helianthus annuus (wild sunflower) and simulated damage of Haplorhynchites aeneus (head-clipping weevil) as a model system, we examined morphological characters and developmental processes that contribute to compensatory ability. We performed a factorial experiment that included three levels of damage (none, the first two, …

Effects Of Management Practices On Grassland Birds: Eastern Meadowlark, Scott D. Hull

United States Geological Survey: Effects of Management Practices on Grassland Birds

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which …

Effects Of Management Practices On Grassland Birds: Wilson’S Phalarope, Jill A. Dechant, Douglas H. Johnson, Lawrence D. Igl, Christopher M. Goldade, Amy L. Zimmerman, Betty R. Euliss

United States Geological Survey: Effects of Management Practices on Grassland Birds

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which …

Effects Of Management Practices On Grassland Birds: Savannah Sparrow, David A. Swanson

United States Geological Survey: Effects of Management Practices on Grassland Birds

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which …

Effects Of Management Practices On Grassland Birds: Lesser Prairie-Chicken, Brent E. Jamison, Jill A. Dechant, Douglas H. Johnson, Lawrence D. Igl, Christopher M. Goldade, Betty R. Euliss

United States Geological Survey: Effects of Management Practices on Grassland Birds

Information on the habitat requirements and effects of habitat management on grassland birds were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the breeding distribution of Lesser Prairie-Chicken in the United States and southern Canada. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental …

Effects Of Management Practices On Grassland Birds: Henslow’S Sparrow, James R. Herkert

United States Geological Survey: Effects of Management Practices on Grassland Birds

were summarized from information in more than 4,000 published and unpublished papers. A range map is provided to indicate the relative densities of the species in North America, based on Breeding Bird Survey (BBS) data. Although birds frequently are observed outside the breeding range indicated, the maps are intended to show areas where managers might concentrate their attention. It may be ineffectual to manage habitat at a site for a species that rarely occurs in an area. The species account begins with a brief capsule statement, which provides the fundamental components or keys to management for the species. A section …

Failure Analysis Research Summary: Mitigating The Effects Of Prolonged Darkness With Low Temperature And Low Light, Julie K. Chard, Giridhar Akula, Bruce Bugbee

NASA

Power loss is a common failure in controlled environments. The duration of power loss can be several days – and even weeks – in space environments. Long-duration power loss and the resulting darkness can cause plants to die unless remedial measures are taken during the power outage. Emergency back-up power from batteries could provide low light and reduced air temperature. Plant metabolism and growth are reduced in low temperature. As metabolism slows, energy requirements are reduced and less light is needed. The temperature should be maintained above the chilling temperature for the plant, which is species dependent. The addition of …

Selected Soybean Plant Introductions With Partial Resistance To Sclerotinia Sclerotiorum, D. D. Hoffman, B. W. Diers, G. L. Hartman, C. D. Nickell, R. L. Nelson, W. L. Pedersen, E. R. Cober, George L. Graef, J. R. Steadman, C. R. Grau, B. D. Nelson, L. E. Del Rio, T. Helms, T. Anderson, V. Poysa, University Of Guelph, W. C. Stienstra

Department of Plant Pathology: Faculty Publications

Sclerotinia stem rot, caused by Sclerotinia sclerotiorum, is a major soybean (Glycine max) disease in north-central regions of the United States and throughout the world. Current sources of resistance to Sclerotinia stem rot express partial resistance, and are limited in number within soybean germ plasm. A total of 6,520 maturity group (MG) 0 to IV plant introductions (PIs) were evaluated for Sclerotinia stem rot resistance in the United States and Canada in small plots or in the greenhouse from 1995 to 1997. Selected PIs with the most resistance were evaluated for resistance in the United States and …

Greenhouse And Field Evaluation Of Biological Control Of Fusarium Head Blight On Durum Wheat, D. A. Schisler, N. I. Khan, Michael J. Boehm, P. J. Slininger

Department of Plant Pathology: Faculty Publications

Fusarium head blight (FHB) is a devastating disease that causes extensive yield and quality losses to wheat and barley. In durum wheat, the pathogen-produced toxin deoxynivalenol (DON) is retained in semolina at ~50%, and the causal agent of FHB, Gibberella zeae, has a strong adverse effect on pasta color. Two bacteria and two yeast strains with known efficacy against G. zeae on hexaploid wheats were produced in liquid culture and assayed on two cultivars of durum wheat in greenhouse bioassays. All antagonists reduced FHB severity on cultivar Renville, and three of the four reduced severity on cultivar Ben, with …

Analyses Of Prairie Restorations At Rock Springs Environmental Center, Decatur, Illinois, Jennifer A. Ward

Masters Theses

Rock Springs Environmental Center was acquired in 1969 by the Macon County Conservation District. Several tracts totaling 1.6 hectares were developed as prairie restorations of varying ages on former farmland starting in 1977. During the summers of 1999 to 2001, 123 species were collected at Rock Springs. Of these, 56 species were collected within the sampling transects. The largest number of species (36 out of 56) was collected in the 1983 tract. The highest importance value of all tracts for any species was 42.6 for Andropogon gerardii. Sorensen's Index of Similarity between tracts ranged from 53.97- 72.97. The coefficient …

Effect Of Habitat Depth On Host Location By Five Species Of Parasitoids (Hymenoptera: Pteromalidae, Chalcididae) Of House Flies (Diptera: Muscidae) In Three Types Of Substrates, Christopher Geden

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

Four species of pteromalid parasitoids [Muscidifurax raptor Girault & Sanders, Spalangia cameroni Perkins, Spalangia endius Walker, Spalangia gemina Boucek, and the chalcidid Dirhinus himalayanus (Masi)] were evaluated for their ability to locate house fly pupae at various depths in poultry manure (41% moisture), fly rearing medium (43% moisture), and sandy soil (4% moisture) from a dairy farm. Searching activity in manure was largely confined to the surface (M. raptor, D. himalayanus, and S. gemina) or to depths of up to 2 cm below the surface (S. endius, S. cameroni). S. cameroni was the …

Strategies For Controlling House Fly Populations Resistant To Cyromazine, Diana C. Crespo, Roberto E. Lecuona, Jerome Hogsette

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

The objectives of this study were to compare, from both biological and economic viewpoints, the impact of various control strategies and evaluate their effect on cyromazine-resistant Musca domestica L., and beneficial house fly pupal parasitoids on caged-layer farms (240,000 hens) in Argentina. The strategies evaluated were: chemical, chemical + cultural, and chemical + cultural + biological (integrated management). The products used were: cyromazine 1% and 50%, DDVP, azamethiphos with and without z-9-tricosene, lime, and the parasitoids Spalangia endius Walker and Muscidifurax raptor Girault & Sanders. In the absence of control measures, fly density increased quickly and the average parasitism rate …