Life Sciences Commons^™

Marketing Contracts, Overconfidence, And Timing In The Canadian Wheat Market, Fabio L. Mattos, Stefanie A. Fryza

Department of Agronomy and Horticulture: Faculty Publications

This paper investigates factors that impact marketing performance in the Canadian wheat market. Using data provided by the Canadian Wheat Board (CWB) for six crop years, results indicate that producers were not able to profitably use all marketing contracts offered by the CWB, earlier pricing tended to generate better performance, there was a negative relationship between activeness and performance (suggesting overconfidence in marketing skills), and performance was generally worse in volatile crop years. Further analysis reveals some of these findings differ when outperforming and underperforming producers are investigated separately, particularly with respect to activeness and volatility.

Rosette Iron Deficiency Transcript And Microrna Profiling Reveals Links Between Copper And Iron Homeostasis In Arabidopsis Thaliana, Brian M. Waters, Samuel A. Mcinturf, Ricardo J. Stein

Department of Agronomy and Horticulture: Faculty Publications

Iron (Fe) is an essential plant micronutrient, and its deficiency limits plant growth and development on alkaline soils. Under Fe deficiency, plant responses include up-regulation of genes involved in Fe uptake from the soil. However, little is known about shoot responses to Fe deficiency. Using microarrays to probe gene expression in Kas-1 and Tsu-1 ecotypes of Arabidopsis thaliana, and comparison with existing Col-0 data, revealed conserved rosette gene expression responses to Fe deficiency. Fe-regulated genes included known metal homeostasis-related genes, and a number of genes of unknown function. Several genes responded to Fe deficiency in both roots and rosettes. …

Composting Manure And Other Organic Materials, Charles S. Wortmann, Charles A. Shapiro

Department of Agronomy and Horticulture: Faculty Publications

The Composting Process

Composting is the aerobic decomposition of manure or other organic materials in the thermophilic temperature range (104-149oF). Composted material is odorless, fine-textured, and low-moisture. It can be bagged and sold for use in gardens or nurseries, or used as fertilizer on cropland with little odor or fly breeding potential. Composting improves the handling characteristics of any organic residue by reducing its volume and weight. Composting can kill pathogens and weed seeds.

Disadvantages of composting organic residues include loss of nitrogen and other nutrients, time for processing, cost for handling equipment, available land for composting, odors, marketing, diversion …

Escape From Preferential Retention Following Repeated Whole Genome Duplications In Plants, James C. Schnable, Xiaowu Wang, J. Chris Pires, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

The well supported gene dosage hypothesis predicts that genes encoding proteins engaged in dose–sensitive interactions cannot be reduced back to single copies once all interacting partners are simultaneously duplicated in a whole genome duplication. The genomes of extant flowering plants are the result of many sequential rounds of whole genome duplication, yet the fraction of genomes devoted to encoding complex molecular machines does not increase as fast as expected through multiple rounds of whole genome duplications. Using parallel interspecies genomic comparisons in the grasses and crucifers, we demonstrate that genes retained as duplicates following a whole genome duplication have only …

2011 Vadose Zone Nitrate Study At Hastings, Ne (Revised), Roy F. Spalding, Martin Toavs

Department of Agronomy and Horticulture: Faculty Publications

In an effort to assist Hastings Utilities in the management of their well-head protection area (WHP A) and to protect the groundwater from the impact of nitrate loading from potential nonpoint and point sources, Hastings Utilities subcontracted with the Department of Agronomy and Horticulture at the University of Nebraska for deep vadose zone coring. Continuous 60-ft soil cores were obtained at 36 sites within the apparent WHP A (Figure 1). The sites were selected by Marty Stange on the basis of availability for sampling, management, landuse , cropping history, and location within the WHPA. Nitrogen analyses of these deep soil …

High-Yield Maize With Large Net Energy Yield And Small Global Warming Intensity, Patricio Grassini, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

Addressing concerns about future food supply and climate change requires management practices that maximize productivity per unit of arable land while reducing negative environmental impact. Onfarm data were evaluated to assess energy balance and greenhouse gas (GHG) emissions of irrigated maize in Nebraska that received large nitrogen (N) fertilizer (183 kg of N·ha⁻¹) and irrigation water inputs (272 mm or 2,720 m³ ha⁻¹). Although energy inputs (30 GJ·ha⁻¹) were larger than those reported for US maize systems in previous studies, irrigated maize in central Nebraska achieved higher grain and net energy yields (13.2 …

Genome-Wide Analysis Of Syntenic Gene Deletion In The Grasses, James C. Schnable, Michael Freeling, Eric Lyons

Department of Agronomy and Horticulture: Faculty Publications

The grasses, Poaceae, are one of the largest and most successful angiosperm families. Like many radiations of flowering plants, the divergence of the major grass lineages was preceded by a whole-genome duplication (WGD), although these events are not rare for flowering plants. By combining identification of syntenic gene blocks with measures of gene pair divergence and different frequencies of ancient gene loss, we have separated the two subgenomes present in modern grasses. Reciprocal loss of duplicated genes or genomic regions has been hypothesized to reproductively isolate populations and, thus, speciation. However, in contrast to previous studies in yeast and teleost …

Identification And Characterization Of Four Missense Mutations In Brown Midrib 12 (Bmr12), The Caffeic O-Methyltranferase (Comt) Of Sorghum, Scott E. Sattler, Nathan A. Palmer, Ana Saballos, Ann M. Greene, Zhanguo Xin, Gautam Sarath, Wilfred Vermerris, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Modifying lignin content and composition are targets to improve bioenergy crops for cellulosic conversion to biofuels. In sorghum and other C4 grasses, the brown midrib mutants have been shown to reduce lignin content and alter its composition. Bmr12 encodes the sorghum caffeic O-methyltransferase, which catalyzes the penultimate step in monolignol biosynthesis. From an EMS-mutagenized TILLING population, four bmr12 mutants were isolated. DNA sequencing identified the four missense mutations in the Bmr12 coding region, which changed evolutionarily conserved amino acids Ala71Val, Pro150Leu, Gly225Asp, and Gly325Ser. The previously characterized bmr12 mutants all contain premature stop codons. These newly identified mutants, along …

Biomass Yield And Nutrient Responses Of Switchgrass To Phosphorus Application, M. K. Kering, J. T. Biermacher, T. J. Butler, J. Mosali, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

Increasing desire for renewable energy sources has increased research on biomass energy crops in marginal areas with low potential for food and fiber crop production. In this study, experiments were established on low phosphorus (P) soils in southern Oklahoma, USA to determine switchgrass biomass yield, nutrient concentrations, and nutrient removal responses to P and nitrogen (N) fertilizer application. Four P rates (0, 15, 30, and 45 kg Pha⁻¹) and two N fertilizer rates (0 and 135 kg Nha⁻¹) were evaluated at two locations (Ardmore and Waurika) for 3 years.While P fertilization had no effect on yield …

Biomass Yield And Nutrient Removal Rates Of Perennial Grasses Under Nitrogen Fertilization, M. K. Kering, T. J. Butler, J. T. Biermacher, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

Perennial grasses may provide a renewable source of biomass for energy production. Biomass yield, nutrient concentrations, and nutrient removal rates of switchgrass (Panicum virgatum L.), giant miscanthus (Miscanthus x giganteus), giant reed (Arundo donax L.), weeping lovegrass [Eragrostis curvula (Shrad.) Nees], kleingrass (Panicum coloratum L.), and Johnsongrass (Sorghum halepense (L.) Pers.) were evaluated at four N fertilizer rates (0, 56, 112, or 168 kg Nha⁻¹) on a Minco fine sandy loam soil in southern Oklahoma. Species were established in 2008 and harvested for biomass in winter of 2009 and 2010. Biomass …

Switchgrass Harvest And Storage, Robert B. Mitchell, Marty R. Schmer

Department of Agronomy and Horticulture: Faculty Publications

The feedstock characteristics of the conversion platform will influence the optimal harvest and post harvest management practices for switchgrass. However, many of the harvest management practices are tied to plant phenology and will be similar across platforms. Proper harvest and storage of switchgrass will help provide a consistent and high-quality feedstock to the biorefinery. Bioenergyspecific switchgrass strains are high-yielding and in most cases can be harvested and baled with commercially available haying equipment. Many options are available for packaging switchgrass for storage and transportation, but large round bales or large rectangular bales are the most readily available and are in …

Crop Management Of Switchgrass, Matt A. Sanderson, Marty R. Schmer, Vance Owens, Pat Keyser, Wolter Elbersen

Department of Agronomy and Horticulture: Faculty Publications

Management of switchgrass for bioenergy and forage share some commonalities, of particular interest in bioenergy crop production is: (1) rapid establishment of switchgrass to generate harvestable biomass in the seeding year, (2) highly efficient management of soil and fertilizer N to minimize external energy inputs, and (3) harvest management to maximize yields of lignocellulose. Bioenergy cropping may entail management for multiple services in addition to biomass yield including soil C sequestration, wildlife habitat, landscape management, and water quality protection. Management is a critical factor especially as land classified as marginal or idle land will be emphasized for bioenergy production to …

Managing Nitrogen And Phosphorus Nutrients For Switchgrass Produced For Bioenergy Feedstock In Phosphorus-Deficient Soil, Mohua Haque, Jon T. Biermacher, Maru Kering, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

There is limited information available explaining the agronomic and economic relationships between yield and nitrogen and phosphorus applications to growing switchgrass produced in phosphorus-deficient soils. The objective of this study was to determine the effects of nitrogen and phosphorus fertilizers on feedstock yield and measures of expected total cost, gross revenue, net return, and breakeven price of feedstock produced in phosphorus-deficient soils in the southern Great Plains. Data were collected from a three-year, two-location agronomic field study conducted in south-central Oklahoma. Two discrete nitrogen treatments (0 and 134 kg ha^-1) and four discrete phosphorus treatments (0, 30, 60 …

Auxin Controls Arabidopsis Adventitious Root Initiation By Regulating Jasmonic Acid Homeostasis, Laurent Gutierrez, Gaëlle Mongelard, Kristýna Floková, Daniel I. Păcurar, Ondrej Novák, Paul E. Staswick, Mariusz Kowalczyk, Monica Păcurar, Gaia Geiss, Catherine Bellini

Department of Agronomy and Horticulture: Faculty Publications

Vegetative shoot-based propagation of plants, including mass propagation of elite genotypes, is dependent on the development of shoot-borne roots, which are also called adventitious roots. Multiple endogenous and environmental factors control the complex process of adventitious rooting. In the past few years, we have shown that the auxin response factors ARF6 and ARF8, targets of the microRNA miR167, are positive regulators of adventitious rooting, whereas ARF17, a target of miR160, is a negative regulator. We showed that these genes have overlapping expression profiles during adventitious rooting and that they regulate each other’s expression at the transcriptional …

Modulation Of Kernel Storage Proteins In Grain Sorghum (Sorghum Bicolor (L.) Moench), Tejinder Kumar, Ismail M. Dweikat, Shirley Sato, Zhengxiang Ge, Natalya Nersesian, Han Chen, Thomas Elthon, Scott Bean, Brian P. Ioerger, Mike Tilley, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Sorghum prolamins, termed kafirins, are categorized into subgroups α, β, and γ. The kafirins are co-translationally translocated to the endoplasmic reticulum (ER) where they are assembled into discrete protein bodies that tend to be poorly digestible with low functionality in food and feed applications. As a means to address the issues surrounding functionality and digestibility in sorghum, we employed a biotechnology approach that is designed to alter protein body structure, with the concomitant synthesis of a co-protein in the endosperm fraction of the grain. Wherein perturbation of protein body architecture may provide a route to impact digestibility by reducing disulphide …

Expected Economic Potential Of Substituting Legumes For Nitrogen In Bermudagrass Pastures, Jon T. Biermacher, The Samuel Roberts Noble Foundation, Inc. Reuter, M.K. Kering, J.K. Rogers, J. Blanton Jr, John A. Guretzky, T.J. Butler

Department of Agronomy and Horticulture: Faculty Publications

Grazing warm-season grass pastures with stocker cattle (Bos taurus) is an important economic activity in the southern Great Plains, and substantial increases in the price of N fertilizer have negatively affected profi tability of forage producers. The goal of the study was to determine if bermudagrass [Cynodon dactylon (L.) Pers.] pastures interseeded with either annual or perennial legumes are more profitable than the conventional method of fertilizing with 112 kg N ha^–1 commercial fertilizer. A completely randomized design grazing study was conducted in south-central Oklahoma during the spring and summer months of 2008, 2009, and 2010. …

Registration Of ‘Ne01481’ Hard Red Winter Wheat, P. Stephen Baenziger, Robert A. Graybosch, Teshome H. Regassa, Lenis Alton Nelson, Robert N. Klein, Dipak K. Santra, D. D. Baltensperger, Lei Xu, Stephen N. Wegulo, Y. Jin, J. Kolmer, Ming-Shun Chen, Guihua Bai

Department of Agronomy and Horticulture: Faculty Publications

‘NE01481’ (Reg. No. CV-1061, PI 659689) hard red winter wheat (Triticum aestivum L.) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS and released in April 2010. NE01481 will be marketed as Husker Genetics brand McGill. In addition to superior agronomic performance, Nebraska wheat growers would like to have increased resistance to Wheat soilborne mosaic virus. NE01481 was selected from the cross NE92458/‘Ike’ that was made in 1995. The pedigree of NE92458 is OK83201/‘Redland’ and the pedigree of OK83201, an experimental line developed by Oklahoma State University is ‘Vona’//‘Chisholm’/‘Plainsman V’. NE01481 was selected with the bulk …

Cover Crop Mixtures For The Western Corn Belt: Opportunities For Increased Productivity And Stability, Samuel E. Wortman, Charles A. Francis, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Achieving agronomic and environmental benefits associated with cover crops oft en depends on reliable establishment of a highly productive cover crop community. The objective of this study was to determine if cover crop mixtures can increase productivity and stability compared to single species cover crops, and to identify those components most active in contributing to or detracting from mixture productivity. A rainfed field experiment was conducted near Mead, Nebraska, United States, in 2010 and 2011. Eight individual cover crop species (in either the Brassicaceae [mustard] or Fabaceae [legume] family) and four mixtures of these species (two, four, six, and eight …

Local Conditions, Not Regional Gradients, Drive Demographic Variation Of Giant Ragweed (Ambrosia Trifida) And Common Sunflower (Helianthus Annuus) Across Northern U.S. Maize Belt, Samuel E. Wortman, Adam Davis, Brian J. Schutte, John L. Lindquist, John Cardina, Joel Felix, Christy L. Sprague, J. Anita Dille, Analiza H. M. Ramirez, Graig Reicks, Sharon A. Clay

Department of Agronomy and Horticulture: Faculty Publications

Knowledge of environmental factors influencing demography of weed species will improve understanding of current and future weed invasions. The objective of this study was to quantify regional-scale variation in vital rates of giant ragweed and common sunflower . To accomplish this objective, a common field experiment was conducted across seven sites between 2006 and 2008 throughout the north central U.S. maize belt. Demographic parameters of both weed species were measured in intra- and interspecific competitive environments, and environmental data were collected within site-years. Site was the strongest predictor of below ground vital rates (summer and winter seed survival and seedling …

High-Resolution Mapping Of Open Chromatin In The Rice Genome, Wenli Zhang, Yufeng Wu, James C. Schnable, Zixian Zeng, Michael Freeling, Gregory E. Crawford, Jiming Jiang

Department of Agronomy and Horticulture: Faculty Publications

Gene expression is controlled by the complex interaction of transcription factors binding to promoters and other regulatory DNA elements. One common characteristic of the genomic regions associated with regulatory proteins is a pronounced sensitivity to DNase I digestion. We generated genome-wide high-resolution maps of DNase I hypersensitive (DH) sites from both seedling and callus tissues of rice (Oryza sativa). Approximately 25% of the DH sites from both tissues were found in putative promoters, indicating that the vast majority of the gene regulatory elements in rice are not located in promoter regions. We found 58% more DH sites in …

Brown Midrib2 (Bmr2) Encodes The Major 4-Coumarate: Coenzyme A Ligase Involved In Lignin Biosynthesis In Sorghum (Sorghum Bicolor (L.) Moench), Ana Saballos, Scott Sattler, Emiliano Sanchez, Timothy P. Foster, Zhanguo Xin, Chulhee Kang, Jeffrey F. Pedersen, Wilfred Vermerris

Department of Agronomy and Horticulture: Faculty Publications

Successful modification of plant cell-wall composition without compromising plant integrity is dependent on being able to modify the expression of specific genes, but this can be very challenging when the target genes are members of multigene families. 4-coumarate:CoA ligase (4CL) catalyzes the formation of 4-coumaroyl CoA, a precursor of both flavonoids and monolignols, and is an attractive target for transgenic down-regulation aimed at improving agro-industrial properties. Inconsistent phenotypes of transgenic plants have been attributed to variable levels of down-regulation of multiple 4CL genes. Phylogenetic analysis of the sorghum genome revealed 24 4CL(-like) proteins, five of which cluster with bona fide …

An Investigation Of Reflective Mulches For Use Over Capillary Mat Systems For Winter-Time Greenhouse Strawberry Production, George E. Meyer, Ellen T. Paparozzi, Elizabeth Walter-Shea, Erin E. Blankenship, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Photosynthethically active radiation (PAR) is a principle environmental variable used by horticultural specialists, agronomists and ecosystem modelers to characterize the quantity and quality of light conducive to plant growth and development. Spatial distribution of PAR in a greenhouse can be quite variable and diffuse throughout the day time photoperiod, especially at low sun angles in northern regions of the United States. Four colors of reflective plastic mulches (white, red, olive, and black) were evaluated for winter-time strawberry (Fragaria × ananassa Duch.) production based on their reflectance and transmittance properties in a double-polyethylene, plastic-glazed Quonset greenhouse inNebraska. The spectral properties …

Effectiveness Of Grass Filters In Reducing Phosphorus And Sediment Runoff, Ahmed Al-Wadaey, Charles S. Wortmann, Thomas G. Franti, Charles A. Shapiro, Dean E. Eisenhauer

Department of Agronomy and Horticulture: Faculty Publications

Surface water contamination can often be reduced by passing runoff water through perennial grass filters. Research was conducted in 2006 to 2008 to evaluate the size of cool season grass filters consisting primarily of tall fescue (Festuca arundinacea Schreb) with some orchard grass (Dactylis glomerata L.) relative to drainage area size in reducing runoff sediment and phosphorus (P). The soil was Pohocco silt loam Typic Eutrochrepts with a median slope of 5.5%. The grass filters occupying 1.1 and 4.3% of the plot area were compared with no filter with four replications. The filters were planted in the V-shaped …

Agriculture And Food In Crisis: Conflict, Resistance, And Renewal [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by Fred Magdoff and Brian Tokar. 2010. Monthly Review Press, New York, New York, United States. 348 p. Paperback, cloth US$ 75.00, paper US$ 18.95, ISBN-13 978-1-58367-226-6.

That doubling of food production over the next four decades will be needed to adequately nourish our human population is not news, but the incredible steps essential to achieve that goal and their political and social implications are less well reported. In this series of 16 essays edited by Fred Magdoff and Brian Tokar, several thoughtful specialists in global food issues explore the historical, biological, economic, energy, political and social dimensions of …

Cultivating A Movement: Excerpts From An Oral History Of Organic Farming And Sustainable Agriculture On California’S Central Coast [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Edited by I. Reti and S. Rabkin, 2011. University of California, Santa Cruz, Library, Santa Cruz, California, United States. 299 p., US$19.95, ISBN 9-780972-33431, paper.

Often the most compelling evidence for success of organic farming comes from the personal stories of farmers. Coupled with reports on the application of science in organics, the practical knowledge of people in the field provides a rich foundation for the ongoing growth of this intriguing sector of the food system. This collection of interviews by the staff of the Regional History Project is one unique activity of the University of California, Santa Cruz library, …

Greenhouse Production Of Strawberries During The Winter, Ellen T. Paparozzi, George E. Meyer, Stacy A. Adams, M. Elizabeth Conley, Benjamin A. Loseke, Paul E. Read

Department of Agronomy and Horticulture: Faculty Publications

Strawberries are one of America’s favorite fruits and are available in grocery stores year round. Given increased shipping and other associated costs as well as the opportunity to provide a fresh, nutritious, local product, our research team is exploring the feasibility of growing strawberries during the winter in Nebraska.

Estimating Construction Costs For A Low-Cost Quonset-Style Greenhouse, David P. Lambe, Stacy A. Adams, Ellen T. Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

Double polyethylene Quonset-style greenhouses offergrowers and farmers a more cost-effective structure than glass- or acrylic-covered structures for growing plants off-season. These greenhouses are especially applicablefor producing off-season high value crops such as fruits and vegetables for local markets. To support this production alternative, this publication contains a list of greenhouse components, the start-up costs associated with these items and an estimate of the number of person hours required to assemble and outfit a 24-foot-by-72-foot double polyethylene, air-inflated greenhouse structure. As there are many options available for building double polyethylene greenhouses, the main purpose of this publication is to identify the …

Quantitative Trait Locus Analysis Of Saturated Fatty Acids In A Population Of Recombinant Inbred Lines Of Soybean, Xianzhi Wang, Guo-Liang Jiang, Marci Green, Roy A. Scott, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] is an important crop which contributes approximately 58% of the world’s oilseed production. Palmitic and stearic acids are the two main saturated fatty acids in soybean oil. Different levels of saturated fatty acids are desired depending on the uses of the soybean oil. Vegetable oil low in saturated fatty acids is preferred for human consumption, while for industrial applications, soybean oil with higher levels of saturated fatty acids is more suitable. The objectives of this study were to identify quantitative trait loci (QTL) for saturated fatty acids, analyze the genetic effects of single QTL …

Structural Variants In The Soybean Genome Localize To Clusters Of Biotic Stress-Response Genes, Leah K. Mchale, William J. Haun, Wayne W. Xu, Pudota B. Bhaskar, Justin E. Anderson, D. L. Hyten, Daniel J. Gerhardt, Jeffrey A. Jeddeloh, Robert M. Stupar

Department of Agronomy and Horticulture: Faculty Publications

Genome-wide structural and gene content variations are hypothesized to drive important phenotypic variation within a species. Structural and gene content variations were assessed among four soybean (Glycine max) genotypes using array hybridization and targeted resequencing. Many chromosomes exhibited relatively low rates of structural variation (SV) among genotypes. However, several regions exhibited both copy number and presence-absence variation, the most prominent found on chromosomes 3, 6, 7, 16, and 18. Interestingly, the regions most enriched for SV were specifically localized to gene-rich regions that harbor clustered multigene families. The most abundant classes of gene families associated with these regions …

Molecular Mapping Of Soybean Rust Resistance In Soybean Accession Pi 561356 And Snp Haplotype Analysis Of The Rpp1 Region In Diverse Germplasm, Ki-Seung Kim, Jair R. Unfried, D. L. Hyten, Reid D. Frederick, Glen L. Hartman, Randall L. Nelson, Qijian Song, Brian W. Diers

Department of Agronomy and Horticulture: Faculty Publications

Soybean rust (SBR), caused by Phakopsora pachyrhizi Sydow, is one of the most economically important and destructive diseases of soybean [Glycine max (L.) Merr.] and the discovery of novel SBR resistance genes is needed because of virulence diversity in the pathogen. The objectives of this research were to map SBR resistance in plant introduction (PI) 561356 and to identify single nucleotide polymorphism (SNP) haplotypes within the region on soybean chromosome 18 where the SBR resistance gene Rpp1 maps. One-hundred F_2:3 lines derived from a cross between PI 561356 and the susceptible experimental line LD02-4485 were genotyped with genetic …