Life Sciences Commons^™

Agroecology As A Science, A Movement And A Practice: A Review, A. Wezel, S. Bellon, T. Doré, Charles A. Francis, D. Vallod, C. David

Department of Agronomy and Horticulture: Faculty Publications

Agroecology involves various approaches to solve actual challenges of agricultural production. Though agroecology initially dealt primarily with crop production and protection aspects, in recent decades new dimensions such as environmental, social, economic, ethical and development issues are becoming relevant. Today, the term ‘agroecology’ means either a scientific discipline, agricultural practice, or political or social movement. Here we study the different meanings of agroecology. For that we analyse the historical development of agroecology. We present examples from USA, Brazil, Germany, and France. We study and discuss the evolution of different meanings agroecology. The use of the term agroecology can be traced …

Detection And Validation Of Single Feature Polymorphisms Using Rna Expression Data From A Rice Genome Array, Sung-Hyun Kim, Prasanna R. Bhat, Xinping Cui, Harkamal Walia, Jin Xu, Steve Wanamaker, Abdelbagi M. Ismail, Clyde Wilson, Timothy J. Close

Department of Agronomy and Horticulture: Faculty Publications

Background: A large number of genetic variations have been identified in rice. Such variations must in many cases control phenotypic differences in abiotic stress tolerance and other traits. A single feature polymorphism (SFP) is an oligonucleotide array-based polymorphism which can be used for identification of SNPs or insertion/deletions (INDELs) for high throughput genotyping and high density mapping. Here we applied SFP markers to a lingering question about the source of salt tolerance in a particular rice recombinant inbred line (RIL) derived from a salt tolerant and salt sensitive parent. Results: Expression data obtained by hybridizing RNA to an oligonucleotide array …

Nutrient And Chemical Properties Of Aging Golf Course Putting Greens As Impacted By Soil Depth And Mat Development, Ty A. Mcclellan, Roch E. Gaussoin, Bob Shearman, Charles S. Wortmann, Martha Mamo, Garald L. Horse, David B. Marx

Department of Agronomy and Horticulture: Faculty Publications

Nutrient and chemical changes in turfgrass sand-based root zones are not well understood. This study was conducted to characterize nutrient and chemical properties in putting greens influenced by root zone mixture and establishment treatment, putting green age, and soil depth. Putting greens were constructed and established with Agrostis stolonifera L. in sequential years from 1997 to 2000. Treatments included root zone mixtures of 80:20 (v:v) sand and sphagnum peat and 80:15:5 (v:v:v) sand, sphagnum peat, and soil, and accelerated versus controlled establishment. In the establishment year, the accelerated treatment received 2.6-, 3.0-, and 2.6-fold more nitrogen, phosphorus, and potassium, respectively, …

Alternative Methods For Wetland Restoration In The Rainwater Basin, Nebraska, Usa, Nancy Nicolai, James L. Stubbendieck

Department of Agronomy and Horticulture: Faculty Publications

South-central Nebraska is recognized as a focal point of the mid-continent migratory waterfowl flyway. Substantial wetland alterations led to a critical need for restoration. Managers have restored wetlands by scraping with heavy earthmoving equipment to remove excess organic material and near-monocultures of reed canarygrass (Phalaris arundinacea L.) but managers report high costs and topsoil perturbation. Moderate livestock grazing was tested to compare results with those achieved with mechanical techniques. Advantages of grazing could include low costs and less soil perturbation. During the 2006 and 2007 growing seasons, we compared cover of bare ground and open water and plant species …

Forage Yields From 2008-2009 Ryegrass, Jagadeesh Mosali, John A. Guretzky, M. Saha, S. Norton

Department of Agronomy and Horticulture: Faculty Publications

Introduction

Livestock and forage production are the largest contributors to agricultural income in the primary service region of the Noble Foundation. The ryegrass (Lolium multiflorum L) variety testing program is designed to provide up-to-date performance information to cooperators and producers in Oklahoma and Texas about ryegrass varieties that are commercially and commonly available. In addition, the program provides a tool to evaluate and compare experimental breeding lines emerging from the Noble Foundation breeding program as well as other public and private breeding programs. The program is intended to furnish producers with supplemental information, aid decision-making and idea formation. The information …

Forage Yields From 2008-2009 Small Grains, Jagadeesh Mosali, John A. Guretzky, M. Saha, J. Baker, S. Norton

Department of Agronomy and Horticulture: Faculty Publications

Introduction

Livestock and forage production are the largest contributors to agricultural income in the primary service region of the Noble Foundation. The small grains variety testing program which includes oats, rye, triticale and wheat is designed to provide up-to-date performance information to producers in Oklahoma and Texas about varieties that are commercially and commonly available. In addition, the program provides a tool to evaluate and compare experimental breeding lines emerging from the Noble Foundation breeding program as well as other public and private breeding programs. The program is intended to furnish producers with supplemental information and to aid decision-making and …

Research Emphasis – Forage And Bioenergy Crop Management, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

Guretzky specializes in research on forage and bioenergy crop management that will assist agricultural producers and landowners in meeting their goals. The first area of research involves Drs. Jon Biermacher and Billy Cook for the evaluation of management practices of switchgrass in forage and bioenergy systems. Objectives include: 1.) assessing potential on-farm biomass yields and production economics of switchgrass; 2.) documenting effects of location, harvest system and nitrogen fertilizer rates on biomass yields, forage quality, stand persistence and nutrient removal rates; 3.) evaluating establishment and biomass production responses to phosphorus and potassium fertilization; 4.) determining how stocker cattle gains on …

High-Yielding Corn Response To Applied Phosphorus, Potassium, And Sulfur In Nebraska, Charles S. Wortmann, Achim R. Dobermann, Richard B. Ferguson, Gary W. Hergert, Charles A. Shapiro, D. D. Tarkalson, Daniel T. Walters

Department of Agronomy and Horticulture: Faculty Publications

Nutrient management recommendations may change as yield levels and efficiency of crop production increase. Recommendations for P, K, and S were evaluated using results from 34 irrigated corn (Zea mays L.) trials conducted in diverse situations across Nebraska. The mean yield was 14.7 Mg ha^-1 with adequate fertilizer applied. Th e median harvest index values were 0.52, 0.89, 0.15, and 0.56 for biomass, P, K, and S, respectively. Median grain yields were 372, 49, and 613 kg kg^-1 of above-ground plant uptake of P, K, and S, respectively. The estimated critical Bray-1 P level for corn response …

Blue Fescue Overseeding Improves Performance Of Fairway Height Buffalograsses, Bekele G. Abeyo, Robert C. Shearman, Roch E. Gaussoin, Leonard A. Wit, Desalegn D. Serba, Ugur Bilgili

Department of Agronomy and Horticulture: Faculty Publications

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] use as a fairway turfgrass is limited in northern portions of its adaptation zone by its extended winter dormancy and tan coloration in early spring and late fall. Cool-season grasses mixed with buffalograss could enhance turfgrass appearance and performance in fall and early spring. Research was conducted near Mead, NE, with eight buffalograss genotypes maintained under fairway conditions to determine the effect of blue fescue (Festuca ovina L. var. glauca Lam.) overseeding rate on turfgrass performance. Interactions were nonsignificant in most cases so main effects are emphasized. Differences were observed between seeding rates and …

Gibberellic Acid Promotes Seed Germination In Penstemon Digitalis Cv. Husker Red, Anderson Machado De Mello, Nereu Augusto Streck, Erin E. Blankenship, Ellen Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

Penstemon seed often shows an inconsistent or a low germination percentage. Although most select cultivars are propagated by cuttings, for export to other countries, seed is preferred. Three experiments were conducted to determine if soaking seed in gibberellic acid (GA₃) would increase seed germination of Penstemon digitalis cv. Husker Red. GA₃ concentrations used were 0, 10, 50, 100, 200, and 500 mg∙L^–1 (first experiment); 0, 500, 1000, and 1500 mg∙L^–1 (second experiment); and 0, 500, and 1000 mg∙L^–1 (third experiment). The first and second experiments were conducted in a growth chamber, whereas the third …

Antibiotic Use In Animal Production: Environmental Concerns, Teshome H. Regassa, Richard K. Koelsch, Charles S. Wortmann, Richard F. Randle, Akwasi A. Abunyewa

Department of Agronomy and Horticulture: Faculty Publications

Introduction

Antibiotic1 use in animal production has led to improved feed use efficiency and increased growth rates. In turn, these resulted in reduced food production costs and reduced excrement of manure nutrients which may cause pollution problems.

On the other hand, antibiotic use leads to antibiotic resistance and a possible reduction in effectiveness of treatment options for both animals and humans. This publication addresses these issues.

Disease-causing microorganisms2, including bacteria,are the most diverse and numerous organisms on earth. Diverse in their habitat, environmental adaptation, and mechanisms of reproduction, they have short generations with high multiplication rates. Such characteristics help develop …

A High-Oleic-Acid And Low-Palmitic-Acid Soybean: Agronomic Performance And Evaluation As A Feedstock For Biodiesel, George L. Graef, Bradley J. Lavallee, Patrick Tenopir, Mustafa Tat, Bruce Schweiger, Anthony J. Kinney, Jon H. Van Gerpen, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Phenotypic characterization of soybean event 335-13, which possesses oil with an increased oleic acid content (> 85%) and reduced palmitic acid content (< 5%), was conducted across multiple environments during 2004 and 2005. Under these conditions, the stability of the novel fatty acid profile of the oil was not influenced by environment. Importantly, the novel soybean event 335-13 was not compromised in yield in both irrigated and non-irrigated production schemes. Moreover, seed characteristics, including total oil and protein, as well as amino acid profile, were not altered as a result of the large shift in the fatty acid profile. The novel oil trait was inherited in a simple Mendelian fashion. The event 335-13 was also evaluated as a feedstock for biodiesel. Extruded oil from event 335-13 produced a biodiesel with improved cold flow and enhanced oxidative stability, two critical fuel parameters that can limit the utility of this renewable transportation fuel.

Shaping The Cross Timbers With Fire And Grazing, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

Recently, our agricultural research team has been asked to provide talks during tours of our Oswalt Road Ranch. The Oswalt Road Ranch is a 4,992-acre property in Love County, Okla., willed to us by D. Joyce Coffey. The Noble Foundation took full control of the property in 2000. The ranch is a valuable piece of property because of its unique natural beauty and potential to support livestock production and wildlife habitat. On the tours, we have been showing off our new state-of-the art livestock handling facilities and providing information about results from recent research on by-product feeds, the Noble Foundation …

A Critical Role Of Two Positively Charged Amino Acids In The Jas Motif Of Arabidopsis Jaz Proteins In Mediating Coronatine- And Jasmonoyl Isoleucine-Dependent Interactions With The Coi1 F-Box Protein, Maeli Melotto, Christy Mecey, Yajie Niu, Hoo Sun Chung, Leron Katsir, Jian Yao, Weiqing Zeng, Bryan Thines, Paul E. Staswick, John Browse, Gregg A. Howe, Sheng Yang He

Department of Agronomy and Horticulture: Faculty Publications

Coronatine is an important virulence factor produced by several pathovars of the bacterial pathogen Pseudomonas syringae. The structure of coronatine is similar to that of a class of plant hormones called jasmonates (JAs). An important step in JA signaling is the SCF^COI1 E3 ubiquitin ligase-dependent degradation of JAZ repressor proteins. We have recently shown that jasmonoyl isoleucine (JA-Ile) promotes physical interaction between Arabidopsis JAZ1 and COI1 (the F-box component of SCF^COI1) proteins, and that the JAIle- dependent COI1–JAZ1 interaction could be reconstituted in yeast cells (i.e. in the absence of other plant proteins). Here we show …

Does The Corn/Soybean Farmer Have Time For Alternative Crops? [Abstract], Lori A. Hoagland, Laurie Hodges, Glenn A. Helmers, James R. Brandle, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

Diversification of traditional row-crop farming in the Corn Belt is seen as advantageous in providing a wider economic base, decreasing economic risk associated with the link between commodity grain and cattle, increasing net farm income, and increasing biodiversity in the region. As farm size has increased to provide sufficient farm income, farm operations during the critical planting and harvesting windows are seen as limits to additional on-farm enterprises.

Soil Nitrogen And Phosphorus Availability For Field-Applied Slurry From Swine Fed Traditional And Low-Phytate Corn, J. S. Paschold, B. J. Wienhold, Richard B. Ferguson, Dennis L. Mccallister

Department of Agronomy and Horticulture: Faculty Publications

Swine (Sus scrofa) slurry contains nutrients essential for crop production but usually contains more P relative to N than is required by most crops, creating the potential for negative environmental impacts. Diet modifications such as low-phytate corn (Zea mays L.) have resulted in improved bioavailability of P and reduced manure P content. A field study was conducted to compare in situ availability of N and P at two sites. One site received three annual additions of manure from swine fed low-phytate corn or traditional corn diets or inorganic fertilizer, surface applied to rainfed no-till sorghum [Sorghum …

Cool-Season Legumes For Southern Pastures, John A. Guretzky, Twain Butler

Department of Agronomy and Horticulture: Faculty Publications

Legumes can improve the production and nutritional value of pastures while reducing nitrogen fertilization requirements. On July 19, 2008, the Noble Foundation will host the "Texoma Pasture Conference" to explain the pros and cons of using legumes in pastures. The Agricultural Division has invited experts from Alabama, Georgia, Kentucky, Oklahoma and Texas to deliver this exciting program. We encourage you to attend this timely event. In the meantime, we will tell you about ongoing research in the Agricultural and Forage Improvement divisions evaluating legumes for pasture.

A goal of our research is to identify best practices for establishing and managing …

Heterologous Expression Of A Plastid Ef-Tu Reduces Protein Thermal Aggregation And Enhances Co2 Fixation In Wheat (Triticum Aestivum) Following Heat Stress, Jianming Fu, Ivana Momcilovic, Thomas E. Clemente, Harold N. Trick, Natalya Nersesian, Zoran Ristic

Department of Agronomy and Horticulture: Faculty Publications

Heat stress is a major constraint to wheat production and negatively impacts grain quality, causing tremendous economic losses, and may become a more troublesome factor due to global warming. At the cellular level, heat stress causes denaturation and aggregation of proteins and injury to membranes leading to alterations in metabolic fluxes. Protein aggregation is irreversible, and protection of proteins from thermal aggregation is a strategy a cell uses to tolerate heat stress. Here we report on the development of transgenic wheat (Triticum aestivum) events, expressing a maize gene coding for plastidal protein synthesis elongation factor (EF-Tu), which, compared to non-transgenic …

Effect Of Sorghum Seedlings, And Previous Crop, On Soil Fluorescent Pseudomonas Spp., Deanna L. Funnell, Jeffrey F. Pedersen, David B. Marx

Department of Agronomy and Horticulture: Faculty Publications

Hypotheses in which sorghum seedlings [Sorghum bicolor (L.) Moench] of different genotypes will differentially modify soil microorganisms and will affect subsequent planting of wheat (Triticum aestivum L.) seedlings, were tested. Wheat cultivar Lewjain, and sorghum genotypes Redlan and RTx433, were planted into soils previously planted with wheat or sorghum in growth chamber experiments. Total culturable fungi and oomycetes, and fluorescent Pseudomonas spp. numbers (cfu) were determined. Pseudomonads were screened for hydrogen cyanide (HCN) production, for the presence of the phlD gene for 2,4-diacetylphloroglucinol production (Phl) and for a region of the operon involved in phenazine-1-carboxylic acid (PCA) production. …

Crop Nitrogen And Phosphorus Utilization Following Application Of Slurry From Swine Fed Traditional Or Low Phytate Corn Diets, J. S. Paschold, B. J. Wienhold, Dennis L. Mccallister, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Field application of swine (Sus scrofa) slurry provides essential nutrients for crop production. The N to P ratio for slurry is lower than needed by most crops resulting in P accumulation when applied at N rates required for crop growth. Low phytate corn (Zea mays L.) (LPC) contains similar amounts of total P but less phytate P than traditional corn (TC) resulting in improved P bioavailability and reduced P excretion by monogastric animals. While manure from swine-fed LPC diets has a higher N to P ratio than that from TC diets, field studies comparing crop utilization of …

Cloning And Characterization Of A Caesalpinoid (Chamaecrista Fasciculate) Hemoglobin: The Structural Transition From A Nonsymbiotic Hemoglobin To A Leghemoglobin, Sabarinathan K. Gopalasubramaniam, Frank A. Kovacs, Fernando Violante-Mota, Paul Twigg, Raul Arrendondo-Peter, Gautam Sarath

Department of Agronomy and Horticulture: Faculty Publications

Nonsymbiotic hemoglobins (nsHbs) and leghemoglobins (Lbs) are plant proteins that can reversibly bind O₂ and other ligands. The nsHbs are hexacoordinate and appear to modulate cellular concentrations of NO and maintain energy levels under hypoxic conditions. The Lbs are pentacoordinate and facilitate the diffusion of O₂ to symbiotic bacteroids within legume root nodules. Multiple lines of evidence suggest that all plant Hbs evolved from a common ancestor and that Lbs originated from nsHbs. However, little is known about the structural intermediates that occurred during the evolution of pentacoordinate Lbs from hexacoordinate nsHbs. We have cloned and characterized a …

Leaf Area Index Simulation In Soybean Grown Under Near-Optimal Conditions, T. D. Setiyono, Albert Weiss, James E. Specht, Kenneth G. Cassman, A. Dobermann

Department of Agronomy and Horticulture: Faculty Publications

Different approaches have been used to simulate leaf area index (LAI) in soybean (Glycine max L. Merr). Many of these approaches require genotype-specific calibration procedures. Studies modeling LAI dynamics under optimal growth conditions with yields close to the yield potential of soybean have remained scarce. A sink-driven approach was developed and evaluated for LAI simulation in soybean under near-optimal environments. The rate of change in expanding leaf area was simulated using the first derivative of a logistic function accounting for plant population density, air temperature, and water deficit. The rate of change in senescing leaf area was also simulated …

Nitrogen Uptake, Fixation And Response To Fertilizer N In Soybeans: A Review, F. Salvagiotti, Kenneth G. Cassman, James E. Specht, Daniel T. Walters, Albert Weiss, Achim R. Dobermann

Department of Agronomy and Horticulture: Faculty Publications

Although relationships among soybean (Glycine max [L.] Merr) seed yield, nitrogen (N) uptake, biological N₂ fixation (BNF), and response to N fertilization have received considerable coverage in the scientific literature, a comprehensive summary and interpretation of these interactions with specific emphasis on high yield environments is lacking. Six hundred and thirty-seven data sets (site–year–treatment combinations) were analyzed from field studies that had examined these variables and had been published in refereed journals from 1966 to 2006. A mean linear increase of 0.013 Mg soybean seed yield per kg increase in N accumulation in above-ground biomass was evident in …

Active Sensor Reflectance Measurements Of Corn Nitrogen Status And Yield Potential, Fernando Solari, John Shanahan, Richard B. Ferguson, James S. Schepers, Anatoly A. Gitelson

Department of Agronomy and Horticulture: Faculty Publications

Active sensor reflectance assessments of corn (Zea mays L.) canopy N status are advocated to direct variable N applications and improve N use efficiency (NUE). Our goals were to determine: (i) growth stage and (ii) sensor vegetation index with greatest sensitivity in assessing N status and grain yield. Variable crop N was generated by supplying N at different amounts and times in three field studies. Chlorophyll meter (CM) and sensor data were gathered at two vegetative (V11 and V15) and two reproductive (R1 and R3) growth stages, using the Crop Circle sensor that measures reflectance in visible (590 nm) …

Establishing Switchgrass For Grazing And Energy, John Biermacher, Billy Cook, John A. Guretzky

Department of Agronomy and Horticulture: Faculty Publications

The purpose of this article is to describe a research project that has been designed to examine the economic feasibility of utilizing switchgrass in a dual-purpose production system that allows for 1) springtime grazing by stocker cattle and 2) fall biomass production that can be harvested and delivered to a biorefinery that will convert it into ethanol. We would also like to report on the production and economic activities associated with establishing the switchgrass that will be used for the study.

Delineating Site-Specific Management Zones For Ph-Induced Iron Chlorosis, T. Kyaw, Richard B. Ferguson, Viacheslav I. Adamchuk, Dennis L. Mccallister, David B. Marx, D. D. Tarkalson

Department of Agronomy and Horticulture: Faculty Publications

Iron chlorosis can limit crop yield, especially on calcareous soil. Typical management for iron chlorosis includes the use of iron fertilizers or chlorosis tolerant cultivars. Calcareous and non-calcareous soil can be interspersed within fields. If chlorosisprone areas within fields can be predicted accurately, site-specific use of iron fertilizers and chlorosis-tolerant cultivars might be more profitable than uniform management. In this study, the use of vegetation indices (VI) derived from aerial imagery, on-the-go measurement of soil pH and apparent soil electrical conductivity (EC_a) were evaluated for their potential to delineate chlorosis management zones. The study was conducted at six …

Adding Value To Swine Manure Through Accurate Prediction Of Organic Nitrogen Availability, Charles S. Wortman, Charles Shapiro, Aaron Nygren

Department of Agronomy and Horticulture: Faculty Publications

Animal manure contains organic and inorganic nitrogen. The inorganic N, which is mostly ammonium-N but nitrate-N can be significant in composted manure, is typically considered to be 100% plant available if there are not significant losses, especially due to volatilization of ammonia-N. The availability of organic N, which is mostly from undigested and partially digested plant material needs to be mineralized to become plant available, is less predictable. Field research was conducted in eastern Nebraska to improve the basis for estimating organic N availability from injected or incorporated swine manure and from surface applied composted and stockpiled FM. The factors …

Farm-Scale Production Cost Of Switchgrass For Biomass, Richard K. Perrin, Kenneth P. Vogel, Marty R. Schmer, Robert B. Mitchell

Department of Agronomy and Horticulture: Faculty Publications

The economic potential of cellulosic biomass from switchgrass has heretofore been evaluated using estimates of farm costs based on extrapolation from experimental data and budget estimates. The objective of the project reported here was to estimate the cost of production that would be experienced by farmers on commercial production situations. Switchgrass was produced as a biomass crop on commercial-scale fields by ten contracting farmers located from northern North Dakota to southern Nebraska. Results showed a wide range of yields and costs across the five production years and ten sites, with an overall average cost of $65.86 Mg^-1 of biomass …

Soybean Sowing Date: The Vegetative, Reproductive, And Agronomic Impacts, A. M. Bastidas, T. D. Setiyono, Achim Dobermann, Kenneth G. Cassman, Roger Wesley Elmore, George L. Graef, James E. Specht

Department of Agronomy and Horticulture: Faculty Publications

The sensitivity of soybean [Glycine max (L.) Merr.] main stem node accrual to ambient temperature has been documented in greenhouse-grown plants but not with field-grown plants in the north-central United States. Biweekly V-node and R-stage, stem node number, internode length, and other traits were quantified in an irrigated split-plot, four-replicate, randomized complete block experiment conducted in Lincoln, NE, in 2003–2004. Main plots were early-, mid-, late- May, and mid-June sowing dates. Subplots were 14 cultivars of maturity groups 3.0 to 3.9. Node appearance was surprisingly linear from V1 to R5, despite the large increase in daily temperature from early …

High-Throughput Genotyping With The Goldengate Assay In The Complex Genome Of Soybean, David L. Hyten, Qijian Song, Ik-Young Choi, Mun-Sup Yoon, James E. Specht, Lakshimi Matukumalli, Randall L. Nelson, Randy C. Shoemaker, Nevin D. Young, Perry B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Large numbers of single nucleotide polymorphism (SNP) markers are now available for a number of crop species. However, the high-throughput methods for multiplexing SNP assays are untested in complex genomes, such as soybean, that have a high proportion of paralogous genes. The Illumina GoldenGate assay is capable of multiplexing from 96 to 1,536 SNPs in a single reaction over a 3-day period. We tested the GoldenGate assay in soybean to determine the success rate of converting verified SNPs into working assays. A custom 384-SNP GoldenGate assay was designed using SNPs that had been discovered through the resequencing of five diverse …