Life Sciences Commons^™

Susceptibility Of Isofamilies Of Spodoptera Frugiperda (Lepidoptera: Noctuidae) To Cry1ac And Cry1fa Proteins Of Bacillus Thuringiensis, Carlos A. Blanco, Maribel Portilla, Juan Luis Jurat-Fuentes, Jaime F. Sanchez, Diego Viteri, Paulina Vega-Aquino, Antonio P. Teran-Vargas, Ausencio Azuara-Dominguez, Juan D. Lopez Jr., R. S. Arias, Yu-Cheng Zhu, David Lugo-Barreras, Ryan Jackson

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

The fall armyworm, Spodoptera frugiperda (J. E. Smith), is one of the most important insect pests on the American continent. Its control has relied primarily on multiple applications of insecticides that can amount to 1,000 g of active ingredient per hectare on some of approximately 30 crops the insect damages. The use of genetically engineered crops that express Bacillus thuringiensis (Bt) Berliner toxins, Bt-corn, Zea mays L.; and Bt-cotton, Gossypium hirsutum L.; are other ways to control this insect. However, fall armyworm is one of the Lepidoptera species least susceptible to Bt proteins, and a case of high tolerance to …

Departments Of Defense And Agriculture Team Up To Develop New Insecticides For Mosquito Control, David Hoel, Julia Pridgeon, Ulrich R. Bernier, Kamal Chauhan, Kumudini Meepagala, Charles Cantrell

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

Mosquito-borne pathogens are among the most important sources of human disease that cause morbidity and mortality worldwide. They include the viruses responsible for deadly outbreaks of yellow fever, Rift Valley fever, eastern equine encephalitis, Japanese encephalitis and dengue, and an assortment of other serious illnesses caused by the etiological agents of West Nile fever, St Louis encephalitis, Murray Valley encephalitis, Venezuelan equine encephalitis and chikungunya disease. Dengue viruses, of which there are 4 serotypes, cause an estimated 50-100 million new illnesses each year (and 25,000 deaths) while the latest chikungunya epidemic has lasted longer, affected more people, and occurred over …

Genome Sequencing And Analysis Of The Model Grass Brachypodium Distachyon, John Vogel, David Garvin, Todd C. Mockler, Jeremy Schmutz, Dan Rokhsar, Michael Bevan

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

Three subfamilies of grasses, the Ehrhartoideae, Panicoideae and Pooideae, provide the bulk of human nutrition and are poised to become major sources of renewable energy. Here we describe the genome sequence of the wild grass Brachypodium distachyon (Brachypodium), which is, to our knowledge, the first member of the Pooideae subfamily to be sequenced. Comparison of the Brachypodium, rice and sorghum genomes shows a precise history of genome evolution across a broad diversity of the grasses, and establishes a template for analysis of the large genomes of economically important pooid grasses such as wheat. The high-quality genome sequence, coupled …

A Comparison Of Cumulative-Germination Response Of Cheatgrass (Bromus Tectorum L.) And Five Perennial Bunchgrass Species To Simulated Field-Temperature Regimes, Stuart P. Hardegree, Corey A. Moffet, Bruce A. Roundy, Thomas A. Jones, Stephen J. Novak, Patrick E. Clark, Frederick B. Pierson, Gerald N. Flerchinger

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

Cheatgrass (Bromus tectorum L.) has come to dominate millions of hectares of rangeland in the Intermountain western United States. Previous studies have hypothesized that one mechanism conferring a competitive advantage to this species is the ability to germinate rapidly at low temperatures in the fall, winter and spring and, therefore, initiate growth and establishment more rapidly than more desirable perennial bunchgrass species. In this experiment, we developed thermal-germination-response models for multiple seedlots of cheatgrass and five perennial grass species. We conducted sensitivity analysis on potential-cumulative-germination response to a 38-year simulation of field-variable conditions of seedbed temperature and moisture. Cheatgrass …

Effects Of Prescribed Fire And Herbicide Application On Cattle Grazing And Herbage Production From Yellow Bluestem Pastures, S. A. Gunter, R. L. Gillen

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

Forage management practices influence the quantity and quality of forage available to grazing cattle. The objectives of this experiment were to determine the effects of prescribed fire or herbicides on the density of forbs, the production and nutritive value of the herbage, and the performance of beef steers grazing Yellow bluestem [Bothriochloa ischaemum (L.) Keng var. ischaemum (Hack.) Celarier and Harlan] pastures. The experiment was conducted in northwestern Oklahoma from 1998 through 2000, and the untreated pastures (control) were not burned or sprayed. The prescribed-fire treatment (PFT) occurred annually between March 27 and April 10. The herbicide treatment (HT) consisted …

Classical Biological Control For The Protection Of Natural Ecosystems, R.G. Van Driesche, R I. Carruthers, T. Center, M.S. Hoddle, J. Hough-Goldstein, L. Morin, L. Smith, D.L. Wagner, B. Blossey, V. Brancatini, R. Casagrande, C.E. Causton, J.A. Coetzee, J. Cuda, J. Ding, S.V. Fowler, J. H. Frank, R. Fuester, J. A. Goolsby, M. Grodowitz, T.A. Heard, M.P. Hill, J.H. Hoffmann, J. Huber, M. Julien, M.T.K. Kairo, M. Kenis, P. Mason, J. Medal, R. Messing, R. Miller, A. Moore, P. Neuenschwander, R. Newman, H. Norambuena, W.A. Palmer, R. Pemberton, A. Perez-Panduro, P.D. Pratt, M. Rayamajhi, S. Salom, D. Sands, S. Schooler, M. Schwarzländer, A. Sheppard, R. Shaw, P.W. Tipping, R.D. Van Klinken

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

Of the 70 cases of classical biological control for the protection of nature found in our review, there were fewer projects against insect targets (21) than against invasive plants (49), in part, because many insect biological control projects were carried out against agricultural pests, while nearly all projects against plants targeted invasive plants in natural ecosystems. Of 21 insect projects, 81% (17) provided benefits to protection of biodiversity, while 48% (10) protected products harvested from natural systems, and 5% (1) preserved ecosystem services, with many projects contributing to more than one goal. In contrast, of the 49 projects against invasive …

Evaluation Of Ulv And Thermal Fog Mosquito Control Applications In Temperate And Desert Environments, Seth C. Britch, Kenneth J. Linthicum, Wayne W. Wynn, Todd W. Walker, Muhammad Farooq, Vincent L. Smith, Cathy A. Robinson, Branka B. Lothrop, Melissa Snelling, Arturo Gutierrez, Hugh D. Lothrop, Jerry D. Kerce, James J. Becnel, Ulrich R. Bernier, Julia W. Pridgeon

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

Ultra-low-volume (ULV) and thermal fog aerosol dispersals of pesticides have been used against mosquitoes and other insects for half a century. Although each spray technology has advantages and disadvantages, only 7 studies have been identified that directly compare their performance in the field. US military personnel currently operating in hot-arid environments are impacted by perpetual nuisance and disease vector insect problems, despite adulticide operations using modern pesticide-delivery equipment such as ULV. None of the identified comparative studies has looked at the relative feasibility and efficacy of ULV and thermal fog equipment against mosquitoes in hot-arid environments. In this study we …

Novel Carboxamides As Potential Mosquito Repellents, Alan R. Katritzky, Zuoquan Wang, Svetoslav Slavov, Dimitar A. Dobchev, C. Dennis Hall, Maia Tsikolia, Ulrich R. Bernier, Natasha M. Elejalde, Gary G. Clark, Kenneth J. Linthicum

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

A model was developed using 167 carboxamide derivatives, from the United States Department of Agriculture archival database, that were tested as arthropod repellents over the past 60 yr. An artificial neural network employing CODESSA PRO descriptors was used to construct a quantitative structure-activity relationship model for prediction of novel mosquito repellents. By correlating the structure of these carboxamides with complete protection time, a measure of repellency based on duration, 34 carboxamides were predicted as candidate mosquito repellents. There were four additional compounds selected on the basis of their structural similarity to those predicted. The compounds were synthesized either by reaction …

Eupatorium Capillifolium Essential Oil: Chemical Composition, Antifungal Activity, And Insecticidal Activity, Nurhayat Tabanca, Ulrich R. Bernier, Maia Tsikolia, James Becnel, Blair Sampson, Chris Werle, Betül Demirci, Kemal Hüsnü Can Başer, Eugene K. Blythe, Cecil Pounders, David E. Wedge

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

Natural plant extracts often contain compounds that are useful in pest management applications. The essential oil of Eupatorium capillifolium (dog-fennel) was investigated for antifungal and insecticidal activities. Essential oil obtained by hydrodistillation of aerial parts was analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC/MS). The major components were determined to be thymol methyl ether (=methyl thymol) (36.3%), 2,5-dimethoxy-p-cymene (20.8%) and myrcene (15.7%). Antifungal activity of the essential oil was weak against the plant pathogens Colletotrichum acutatum, C. fragariae, and C. gloeosporioides in direct bioautography assay. The E. capillifolium oil showed promising repellent activity against …

Tcjp An Improved Method To Quantify Puccinia Coronata F. Sp. Avenae Dna In The Host Avena Sativa, M. Acevedo, E. W. Jackson, A. Sturbaum, H. W. Ohm, J. M. Bonman

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

Identification and genetic mapping of loci conferring resistance to polycyclic pathogens such as the rust fungi depends on accurate measurement of disease resistance. We converted an absolute quantification assay of Puccinia coronata DNA to a relative assay by adding a TaqMan^® primers/probe set specific to the oat β-actin gene to simplify and improve quantification of fungal infection. The new multiplex assay estimates the amount of fungal DNA in a sample relative to the amount of host DNA and requires fewer and less labour-intensive steps than previous assays. The relative fungal DNA assay (RFDNA) reliably detected and quantified both host …

Tillage Depth Effects On Soil Physical Properties, Sugarbeet Yield, And Sugarbeet Quality, J. D. Jabro, W. B. Stevens, W. M. Iversen, R. G. Evans

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

Tillage depth influences the soil–water–plant ecosystem, thereby affecting crop yield and quality. The effects of tillage depth on soil physical properties and sugarbeet (Beta vulgaris L.) yield and quality were evaluated. A field study composed of two tillage depths [10 cm, referred to as shallow (ST), and 20 cm, referred to as deep (DT)] was conducted on a Lihen sandy loam soil in spring 2007 at the Agricultural Research Service (ARS) irrigated research farm near Williston, North Dakota. Soil bulk density (ρb), gravimetric water content (θw), and saturated hydraulic conductivity (Ks) were measured three times during the growing season …

Nutrient Accumulation And Photosynthesis In Glyphosate-Resistant Soybeans Is Reduced Under Glyphosate Use, Luiz Henrique Saes Zobiole, Rubem Silvério De Oliveira Jr., Robert John Kremer, Antonio Saraiva Muniz, Adilson De Oliveira Jr.

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

Global production of glyphosate-resistant (GR) soybean [Glycine max (L.) Merr.] continues to increase annually; however, there are no particular specific fertilizer recommendations for the transgenic varieties used in this system largely because reports of glyphosate effects on mineral nutrition of GR soybeans are lacking. Several metabolites or degradation products of glyphosate have been identified or postulated to cause undesirable effects on GR soybeans. In this work we used increasing glyphosate rates in different application on cv. ‘BRS 242 GR’ in order to evaluate photosynthetic parameters, macro- and micronutrient uptake and accumulation and shoot and root dry …

Permanent Genetic Resources Added To The Molecular Ecology Resources Database 1 February 2010–31 March 2010, D. Aurelle, M. R. Pooler, T. A. Rinehart, B. E. Scheffler, Molecular Ecology Resources Primer Development Consortium

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

This article documents the addition of 228 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Anser cygnoides, Apodemus flavicollis, Athene noctua, Cercis canadensis, Glis glis, Gubernatrix cristata, Haliotis tuberculata, Helianthus maximiliani, Laricobius nigrinus, Laricobius rubidus, Neoheligmonella granjoni, Nephrops norvegicus, Oenanthe javanica, Paramuricea clavata, Pyrrhura orcesi and Samanea saman. These loci were cross-tested on the following species: Apodemus sylvaticus, Laricobius laticollis and Laricobius osakensis (a proposed new species currently being described).

Weed Genomics Advance: A Commentary, Stephen O. Duke, Jonathan Gressel

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

A recent book edited by Neal Stewart summarized the salient information about the genomics of weeds. It is a relatively slim volume, in part because so little is known of weed genomics. The rapidly evolving weeds of modern agriculture cry out for understanding their evolution at the genomic level. Still, granting agencies have been reluctant to fund weed genomics in the past, stating that it was enough to support the sequencing of economically important plants (crops), and forgetting that there may be use to sequencing plants that have extremely negative economicimpactsonthose crops. This attitude hasbeenchanging, and the costs have come …

Thermal And Mechanical Properties Of Compression-Molded Pmdi-Reinforced Pcl/Gluten Composites, Abdellatif Mohamed, Victoria L. Finkenstadt, Sherald H. Gordon, Debra E. Palmquist

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

Many biopolymers and synthetic polymers composites were developed by different researchers for environmental protection and for cost reduction. One of these composites is polycaprolactone (PCL) and vital wheat gluten or wheat flour composites were prepared and compatibilized with polymeric diphenylmethane diisocyanate (pMDI) by blending and compression-molding. PCL/pMDI blend exhibited glass transition (T_g) at -67 °C (0.20 J/g/ °C) and vital gluten at 63 °C (0.45 J/g/ °C), whereas no T_g was recorded for wheat flour. Although T_g was unmistakable for either PCL or gluten, all composite exhibited one T_g, which is strong indication of …

Horticulture Of Ribes, K. E. Hummer, A. Dale

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

The genus Ribes L., known as currants and gooseberries, contains more than 150 diverse species indigenous throughout the northern hemisphere and along the Rocky Mountain, Sierra Nevada and Sierra Madres in North America through mountain ranges of Central America to the Andes in South America. Beginning in the 1400s, four main crop types, black currants (Ribes, subgenus: Ribes, section: Botrycarpum), red and white currants (Ribes, subgenus: Ribes, section: Ribes) and gooseberries (Ribes, subgenus: Grossularia) were domesticated from European species. American and Eurasian species were selected and combined into …

Russia’S Agricultural Imports: Will The High Growth Of The 2000s Continue?, William M. Leifert, Olga Liefert, Mathew Shane

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

Russia’s agricultural imports during the 2000s have grown substantially, from €7.4 billion in 2000 to €19.2 billion in 2007 (Figure 1). The import growth has made Russia the second largest agricultural importer among emerging market economies, after China. The main imports are meat, highly processed products, fruits and vegetables (Figure 2). Russia’s agricultural exports have also grown during this time, though from a much lower base in value terms (and with most of the increase coming just from grain).

Europe has benefited strongly from the rise in Russia’s agricultural imports. During this decade, Russia has been the EU’s second largest …

Drivers Impacting The Adoption Of Sustainable Agricultural Management Practices And Production Systems Of The Northeast And Southeast United States, G. F. Sassenrath, J. M. Halloran, D. Archer, R. L. Raper, J. Hendrickson, P. Vadas, J. Hanson

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

Agricultural production responds to social, political, economic, environmental, and technological drivers that influence producers’ decisions and shape the individual systems through modification of management practices, crop and livestock mix, and marketing strategy. We use an interview and discussion approach with producer panels to examine production systems in the eastern United States and explore key drivers impacting their unique characteristics and development. The internal social driver that values the farming lifestyle is a principle factor that leads people to choose farming. Irrespective of location, farming is first and foremost a lifestyle choice. The choice of type of production system is partly …

Elevated Co2 Effects On Semi-Arid Grassland Plants In Relation To Water Availability And Competition, Feike A. Dijkstra, Dana Blumenthal, Jack A. Morgan, Daniel R. Lecain, Ronald F. Follett

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

1. It has been suggested that much of the elevated CO₂ effect on plant productivity and N cycling in semi-arid grasslands is related to a CO₂-induced increase in soil moisture, but the relative importance of moisture-mediated and direct effects of CO₂ remain unclear.

2. We grew five grassland species common to the semi-arid grasslands of northern Colorado, USA, as monocultures and as mixtures of all five species in pots. We examined the effects of atmospheric CO₂ concentration (ambient vs. 780 p.p.m.) and soil moisture (15 vs. 20% m⁄m) on plant biomass and plant N uptake. …

Effects Of A New Waste-Processing By-Product On Soil And Vegetation At Fort Campbell, Tennessee, R. R. Busby, D. L. Gebhart, H. A. Torbert, J. O. Dawson, G. A. Bollero, K. N. Potter, D. R. Curtin

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

A garbage-processing technology has been developed that sterilizes and separates inorganic and organic components of municipal solid waste. A study was initiated to evaluate the uncomposted organic by-product of this process as a soil amendment for establishing native prairie grasses on disturbed Army training lands. The waste was incorporated into a silt loam soil at Fort Campbell Military Reservation in the central United States. The waste material was applied at rates of 0, 4.5, 9, 18, and 36 Mg ha^-1 and seeded with native prairie grasses to assess its effects on vegetation for two growing seasons, with an additional …

Cloning, Expression, And Immunogenicity Of Flavobacterium Columnare Heat Shock Protein Dnaj, Oscar Olivares-Fuster, Jeffery S. Terhune, Craig A. Shoemaker, Covadonga R. Arias

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

The Flavobacterium columnare heat shock protein (HSP) gene dnaJ* was isolated, cloned, expressed, and used as an antigen in a recombinant vaccine strategy for channel catfish Ictalurus punctatus. The F. columnare dnaJ* sequence was obtained from genomovars I and II and showed intraspecies variability. Recombinant protein was expressed and purified from Escherichia coli cultures and injected intraperitoneally (12 lg of purified DnaJ/fish) into fingerling channel catfish. In addition, induced (expressing the recombinant DnaJ) and uninduced (no recombinant protein being produced) E. coli cultures were also used to immunize fish. At 28 d postimmunization, antibody response was evaluated and the …

Soybase, The Usda-Ars Soybean Genetics And Genomics Database, David Grant, Rex T. Nelson, Steven B. Connon, Randy C. Shoemaker

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

SoyBase, the USDA-ARS soybean genetic database, is a comprehensive repository for professionally curated genetics, genomics and related data resources for soybean. SoyBase contains the most current genetic, physical and genomic sequence maps integrated with qualitative and quantitative traits. The quantitative trait loci (QTL) represent more than 18 years of QTL mapping of more than 90 unique traits. SoyBase also contains the wellannotated ‘Williams 82’ genomic sequence and associated data mining tools. The genetic and sequence views of the soybean chromosomes and the extensive data on traits and phenotypes are extensively interlinked. This allows entry to the database using almost any …

Production Characteristics And Body Composition Of Juvenile Cobia Fed Three Different Commercial Diets In Recirculating Aquaculture Systems, Charles R. Weirich, Paul S. Wills, Richard M. Baptiste, Marty A. Riche

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

The effect of feeding three commercial diets on production characteristics and body composition of juvenile cobia Rachycentron canadum reared using recirculating aquaculture systems (RASs) was assessed in a 56-d growth trial. Juvenile cobia (mean weight ± SE, 29.2 ± 0.7 g) were stocked into three 8-m³ tanks in each of four RASs at an initial density of 1.2 kg/m³. After stocking, fish were fed one of three commercial diets: Hybrid Striped Bass diet (HSB; 44% protein, 12% lipid), Finfish Gold diet (GOLD; 42% protein, 16% lipid), or Marine Grower diet (MG; 50% protein, 15% lipid), all at …

Comparisons Of Sperm Storage Tubule Distribution And Number In 4 Strains Of Mature Broiler Breeders And In Turkey Hens Before And After The Onset Of Photostimulation, M. R. Bakst, A. M. Donoghue, D. E. Yoho, J. R. Moyle, S. M. Whipple, M. J. Camp, G. Q. Liu, R. K. Bramwell

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

The biological basis of sustained fertility in broiler and turkey hens is their capacity to store sperm in the oviductal sperm storage tubules (SST) located in the uterovaginal junction. The objectives of this study were to determine if the numbers of SST varied between 4 strains of broiler breeders and determine the number of SST in the turkey before (less than 9 d of photostimulation) and after (up to 22 d of photostimulation and laying) photostimulation. No statistical differences were observed in SST numbers in the 4 strains of broilers examined or in turkey hens before and after the onset …

Role Of The Oviduct In Maintaining Sustained Fertility In Hens, M. R. Bakst

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

In poultry, sperm transferred by natural mating or AI into the distal end of the vagina immediately begin their ascent to the utero-vaginal junction (UVJ) at the anterior end of the vagina. However, due to an intense selection process in the vagina, less than 1% of the sperm transferred actually reach the UVJ. Those sperm that do reach the UVJ enter numerous tubular invaginations of the vagina’s surface epithelium located in the UVJ mucosa, collectively referred to as the sperm-storage tubules (SST). Sperm residing in the SST lumen are capable of surviving up to several weeks while retaining their fertilizing …

Proteomic Analysis Of The Major Cellular Proteins Of Bovine Trophectoderm Cell Lines Derived From Ivp, Parthenogenetic And Nuclear Transfer Embryos: Reduced Expression Of Annexins I And Ii In Nuclear Transfer-Derived Cell Lines, Neil C. Talbot, Anne M. Powell, Thomas J. Caperna, Wesley M. Garrett

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

Trophectoderm cell lines were established from 8-day in vitro-cultured embryos of cattle derived from fertilization (IVF), somatic cell nuclear transfer (NT), or parthenogenetic activation (P) of in vitro-matured oocytes and from five 8-day-old in vivo (V) embryos. The most abundant cellular proteins of 5 V-, 16 NT-, 12 P-, and 16 IVF-derived cell lines were compared by 2D-gel electrophoresis and mass spectrometry; that is, the unaltered thiourea/urea extract of each cell culture was analyzed. Common protein spots (n = 118) were examined, and 95% were identified with significant scores from protein and gene database searches. Of the proteins …

Fluid Fertilizer’S Role In Sustaining Soils Used For Bio-Fuels Production, John L. Kovar, Douglas L. Karlen

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

Fast pyrolysis is optimized for production of bio-oil. Product yields are typically ~65% bio-oil, 20% biochar, 15% syngas.

Project Objective

To investigate N, P, K, and S dynamics in a comprehensive residue removal, tillage, and nutrient management study

Project Treatments

*Residue removal: 0, 50%, 90%

*Tillage: chisel plow, no-till

*Nutrient management: conventional (30K plants/A), high input (44K plants/A)

•Bio-char: 0, 4.32 tons/A, 8.25 tons/A

•Cover crops: annual, perennial

2009 Soil Test Levels

2009 Nutrient Management

Field Measurements

•Stand counts

•Whole-plant samples at V6

•Ear-leaf samples at mid-silk

•Grain yield and moisture

•Stover yield and moisture

•Grain and stover nutrient content

A Quantitative Phosphorus Loss Assessment Tool For Agricultural Fields, Michael J. White, Daniel E. Storm, Philip R. Busteed, Michael D. Smolen, Hailin Zhang, Garey A. Fox

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

In the United States, government sponsored conservation programs are under increasing pressure to quantify the environmental benefits of practices they subsidize. To meet this objective, conservation planners need tools to accurately predict phosphorus (P) loss from agricultural lands. Existing P export coefficient based tools are easy to use, but do not adequately account for local conditions. Hydrologic and water quality models are more accurate, but are prohibitively complex for conservation planners to use. Pasture Phosphorus Management (PPM) was developed as a user-friendly P and sediment loss prediction tool based on the Soil and Water Assessment Tool (SWAT), a popular comprehensive …

Herbicides For Establishing Switchgrass In The Central And Northern Great Plains, Robert B. Mitchell, Kenneth P. Vogel, John Berdahl, Robert A. Masters

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

Weed interference limits switchgrass (Panicum virgatum L.) establishment from seed. Our objectives were to determine the effect of selected post-plant, preemergence herbicides on stand establishment and subsequent biomass yields of adapted upland switchgrass cultivars grown in three environments in the Central and Northern Great Plains. A separate experiment was conducted in eastern Nebraska to determine if there were any differences among switchgrass ecotypes for herbicide tolerance to the optimal herbicide combination. Herbicides applied immediately after planting were different concentrations of atrazine [Aatrex 4L^®; 6- chloro-N-ethyl-N′-(1-methylethyl)-1,3,5-triazine-2,4-diamine], quinclorac (Paramount^®; 3,7-Dichloro-8-quinolinecarboxylic acid), atrazine+quinclorac, imazapic …

Monitoring And Analyzing Process Streams Towards Understanding Ionic Liquid Pretreatment Of Switchgrass (Panicum Virgatum L.), Rohit Arora, Chithra Manisseri, Chenlin Li, Markus D. Ong, Henrik Vibe Scheller, Kenneth P. Vogel, Blake A. Simmons, Seema Singh

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

Fundamental understanding of biomass pretreatment and its influence on saccharification kinetics, total sugar yield, and inhibitor formation is essential to develop efficient next-generation biofuel strategies, capable of displacing fossil fuels at a commercial level. In this study, we investigated the effect of residence time and temperature during ionic liquid (IL) pretreatment of switchgrass using 1-ethyl-3-methyl imidazolium acetate. The primary metrics of pretreatment performance are biomass delignification, xylan and glucan depolymerization, porosity, surface area, cellulase kinetics, and sugar yields. Compositional analysis and quantification of process streams of saccharides and lignin demonstrate that delignification increases as a function of pretreatment temperature and …