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Soybean

2013

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Association Between Stink Bug Damage And The Incidence Of Phomopsis Longicolla In Mississippi Soybean Production, Joshua Lunn Jones Dec 2013

Association Between Stink Bug Damage And The Incidence Of Phomopsis Longicolla In Mississippi Soybean Production, Joshua Lunn Jones

Theses and Dissertations

Stink bugs (Hemiptera: Pentatomidae) are key pests of soybean, Glycine max (L.), in Mississippi. Historically, yield loss derived from direct feeding by stink bugs has been considered the greatest threat to producers. However, quality reductions resulting from seed infections caused by microorganisms including Phomopsis longicolla are also a concern. Experiments were conducted in 2010 and 2011 to determine if stink bugs are associated with the incidence of P. longicolla in Mississippi soybean production. Data from experiments suggest that stink bugs are capable of transporting P. longicolla between two points. Data further suggest stink bugs and P. longicolla have the potential …


Arkansas Soybean Performance Tests 2013, R. D. Bond, D. G. Dombek, J. A. Still, R. M. Pryor Dec 2013

Arkansas Soybean Performance Tests 2013, R. D. Bond, D. G. Dombek, J. A. Still, R. M. Pryor

Arkansas Agricultural Experiment Station Research Series

Soybean variety and strain performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture Arkansas Crop Variety Improvement Program. The tests provide information to companies developing varieties and/or marketing seed within the State, and aid the Arkansas Cooperative Extension Service in formulating variety recommendations for soybean producers.


Immobilization Of Lead In Contaminated Firing Range Soil Using Biochar, Deok Hyun Moon, Jae-Woo Park, Yoon-Young Chang, Yong Sik Ok, Sang Soo Lee, Mahtab Ahmad, Agamemnon Koutsospyros, Jeong Hun Park, Kitae Baek Dec 2013

Immobilization Of Lead In Contaminated Firing Range Soil Using Biochar, Deok Hyun Moon, Jae-Woo Park, Yoon-Young Chang, Yong Sik Ok, Sang Soo Lee, Mahtab Ahmad, Agamemnon Koutsospyros, Jeong Hun Park, Kitae Baek

Civil Engineering Faculty Publications

Soybean stover-derived biochar was used to immobilize lead (Pb) in military firing range soil at a mass application rate of 0 to 20 wt.% and a curing period of 7 days. The toxicity characteristic leaching procedure (TCLP) was performed to evaluate the effectiveness of the treatment. The mechanism responsible for Pb immobilization in military firing range soil was evaluated by scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray absorption fine structure (XAFS) spectroscopy analyses. The treatment results showed that TCLP Pb leachability decreased with increasing biochar content. A reduction of over 90 % in Pb leachability was achieved upon …


Postemergence And Residual Control Of Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) With Dicamba, Clifford Blake Edwards Aug 2013

Postemergence And Residual Control Of Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) With Dicamba, Clifford Blake Edwards

Theses and Dissertations

Onarm research was conducted in 2011 and 2012 to determine the postemergence and residual control by dicamba of glyphosate-resistant (GR) Palmer amaranth (Amaranthus palmeri S. Wats.). Preemergence dicamba at 0, 0.28, 0.56, and 1.1 kg ae ha-1 and 0.07 kg ae ha-1 flumioxazin was applied at 30, 15 and 0 days prior to planting. Postemergence dicamba at 0.28, 0.56, and 1.1 kg ae ha-1 with and without 0.84 kg ae ha-1 glyphosate was applied to 5, 10 and 15 cm Palmer amaranth. In addition, a greenhouse experiment was conducted in 2012 to evaluate and confirm the optimum rate for control …


Spatial Distributions Of Rhizoctonia Species In Soybean Fields Undergoing Annual Rotations With Rice, Terry Neil Spurlock Aug 2013

Spatial Distributions Of Rhizoctonia Species In Soybean Fields Undergoing Annual Rotations With Rice, Terry Neil Spurlock

Graduate Theses and Dissertations

Aerial blight is caused by Rhizoctonia solani AG1-IA. This pathogen also causes sheath blight of rice. In Arkansas, many soybean and rice fields undergo an annual rotation of these two crops which facilitates a continuous source of inoculum from one year to the next. Aerial blight is a two stage disease in that R. solani AG1-IA colonizes the plant during the early vegetative growth stages and then aerial blight develops after the soybean canopy closes in the later reproductive stages of development. As a result of the upper portion of the canopy often being asymptomatic, significant yield loss can occur …


Genome-Wide Association Mapping Identifies Qtls And Candidate Genes For Salt Tolerance In Soybean, Lei Huang Aug 2013

Genome-Wide Association Mapping Identifies Qtls And Candidate Genes For Salt Tolerance In Soybean, Lei Huang

Graduate Theses and Dissertations

Salinity is a common abiotic stress causing soybean yield loss worldwide. Use of tolerant cultivars is an effective and economic approach to coping with this stress. Toward this, research is needed to identify salt-tolerant germplasm and better understand the genetic and molecular basis of salt tolerance in soybean. The objectives of this study were to identify salt-tolerant genotypes, to search for SNPs and QTLs associated with salt tolerance, and to identify candidate salt tolerance genes. A total of 192 diverse soybean lines and cultivars were screened for salt tolerance in the greenhouse based on visual leaf scorch scores after 15 …


Soybean (Glycine Max) Response To Imazosulfuron Drift And Carryover From Rice (Oryza Sativa), Sandeep Singh Rana Aug 2013

Soybean (Glycine Max) Response To Imazosulfuron Drift And Carryover From Rice (Oryza Sativa), Sandeep Singh Rana

Graduate Theses and Dissertations

In the Midsouth, soybean is often grown in close proximity to rice or in rotation with rice. Herbicides used in rice can injure soybean via drift or carryover. Consequently, field trials were conducted to determine the response of soybean (cv. AG 4703) to imazosulfuron drift and carryover (at Fayetteville, Marianna, Keiser and Pine Tree, AR) from rice. To assess the potential for carryover, soybean was planted into rice fields treated the previous year with imazosulfuron (rotation study). To evaluate in-season sensitivity of soybean to imazosulfuron (tolerance study) relative to halosulfuron, a common sulfonylurea herbicide applied to rice, both imazosulfuron and …


Selecting Drought Tolerant Soybean Genotypes Using Qtls Associated With Shoot Ureide And Nitrogen Concentrations, Alejandro Bolton Aug 2013

Selecting Drought Tolerant Soybean Genotypes Using Qtls Associated With Shoot Ureide And Nitrogen Concentrations, Alejandro Bolton

Graduate Theses and Dissertations

In soybean, nitrogen fixation is more sensitive to drought than other physiological processes like photosynthesis. The sensitivity of nitrogen fixation to drought has been associated with high shoot concentrations of ureide and nitrogen under well-watered conditions. Previous research by Hwang et al. (2013) detected quantitative trait loci (QTLs) in a KS4895 by Jackson population associated with shoot ureide and nitrogen concentrations. The present research evaluated the use of these QTLs in selecting genotypes with drought tolerant nitrogen fixation. Our objectives were to compare actual versus expected phenotype of recombinant inbreed lines (RILs) selected using molecular markers, and to evaluate the …


High Yield Soybean Management: Planting Practices, Nutrient Supply, And Growth Modification, Evan Sonderegger Aug 2013

High Yield Soybean Management: Planting Practices, Nutrient Supply, And Growth Modification, Evan Sonderegger

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

Growers are constantly seeking ways to improve yield in soybean [Glycine max (L.) Merr.]. There has been much interest in the use of selected alternative practices to maximize soybean yield. These practices include planting soybean at higher than recommended seeding rates, planting soybean in narrow rows, breaking apical dominance to induce branching, application of strobilurin fungicides prophylactically to minimize disease and extend the seed filling period, the use of N fertilizer both in furrow and foliar applied, and the use of seed treatments to promote early stand establishment and health. Field studies were conducted at the University of Nebraska …


A Low-Fat Diet Containing Heated Soybean Oil Promotes Hyperglycemia In C57bl/6j Mice, Olivia Lane Middleton Jul 2013

A Low-Fat Diet Containing Heated Soybean Oil Promotes Hyperglycemia In C57bl/6j Mice, Olivia Lane Middleton

Nutrition Theses

A Low-fat Diet Containing Heated Soybean Oil Promotes Hyperglycemia in C57BL/6J Mice

Introduction: The metabolic effects of consuming mildly oxidized lipids as compared to highly oxidized lipids are not well documented. Consumption of highly oxidized polyunsaturated fatty acids, even in a low-fat diet, may be a threat to one’s health. Previous studies in our lab have shown that mice consuming soybean oil heated for 3 hours, compared to unheated, gain less body weight, but more fat pad mass, and 3T3-L1 adipocytes treated with soybean oil heated for ≥ 6 hours have abrogated triglyceride accumulation. Another study showed that rats fed …


Identification Of Cyclophilin Gene Family In Soybean And Characterization Of Gmcyp1, Hemanta Raj Mainali Jul 2013

Identification Of Cyclophilin Gene Family In Soybean And Characterization Of Gmcyp1, Hemanta Raj Mainali

Electronic Thesis and Dissertation Repository

I identified members of the Cyclophilin (CYP) gene family in soybean (Glycine max) and characterized the GmCYP1, one of the members of soybean CYP. CYPs belong to the immunophilin superfamily with peptidyl-prolyl cis-trans isomerase (PPIase) activity. PPIase catalyzes the interconversion of the cis- and trans-rotamers of the peptidyl-prolyl amide bond of peptides. After extensive data mining, I identified 62 different CYP genes in soybean (GmCYP1 to GmCYP62), of which 8 are multi-domain proteins and 54 are single domain proteins. At least 25% of the GmCYP genes are expressed in soybean. GmCYP1 …


Characterization, Inheritance, And Marker Identification Of Potential Novel Genes Conditioning Resistance To Multiple Races Of Cercospora Sojina K. Hara Of Soybean (Glycine Max L.), James Brewer Blessitt May 2013

Characterization, Inheritance, And Marker Identification Of Potential Novel Genes Conditioning Resistance To Multiple Races Of Cercospora Sojina K. Hara Of Soybean (Glycine Max L.), James Brewer Blessitt

Theses and Dissertations

Soybean is an economically important crop. It is a selfertilized species grown on vast contiguous acres. These facts predispose soybean to disease epidemics. Cercospora sojina, causal agent of frogeye leaf spot, has reduced United States soybean productivity 0.3 percent on average per year between 2008 and 2010. Several states have reported the pathogen developing resistance to the strobilurin class of fungicides. To date genetic host resistance has been identified as single dominant genes (Rcs1, Rcs2, and Rcs3). However, the lifespans of Rcs1 and Rcs2 were 10 and 16 years respectively. Currently, the Rcs3 locus has been utilized in all major …


Effects Of Leaflet Orientation And Root Morphology On Physiological Traits And Yield In Soybeans., Richard Dewayne Johnson May 2013

Effects Of Leaflet Orientation And Root Morphology On Physiological Traits And Yield In Soybeans., Richard Dewayne Johnson

Doctoral Dissertations

Drought is the most important abiotic stress adversely affecting soybean (Glycine max (L.) Merr.) yield. Leaflet orientation has been shown to reduce leaflet temperatures and transpiration while root morphology has been related to slower wilting phenotypes. The objective of this study was to investigate effects of leaflet orientation and rooting morphology on whole plant transpiration, yield, water use efficiency, and other physiological traits in soybeans using grafting techniques, population lines, near-isogenic lines, and restrained leaf canopy experiments. Experiments were conducted in Knoxville, TN with additional yield trial plots at Springfield, Spring Hill, and Milan, TN. Data were collected on …


Comparison Of Roundup Ready And Conventional Soybean (Glycine Max L.) Weed Control Systems For Optimizing Yield And Economic Profitability, Brittany Lee Gaban May 2013

Comparison Of Roundup Ready And Conventional Soybean (Glycine Max L.) Weed Control Systems For Optimizing Yield And Economic Profitability, Brittany Lee Gaban

Masters Theses

Research was conducted in 2010, 2011 and 2012 at the East Tennessee Research and Education Center in Knoxville, TN, in order to compare differences in soybean yield among differing levels of weed control within Roundup Ready® [Glyphosate-resistant] (RR)and conventional soybean cultivars to gain a better understanding of the impact different intensities of weed control have on RR and conventional cropping systems. Results determined that after applying the weed control regimens, there was no significant difference (p

Glyphosate resistant weeds introduce new challenges and create a more costly weed control regimen, especially when using a RR based soybean cultivation operation. Therefore, …


Effects Of Late Planting Dates, Maturity Groups And Management Systems On Growth, Development And Yield Of Soybean In South Carolina, Mengxuan Hu May 2013

Effects Of Late Planting Dates, Maturity Groups And Management Systems On Growth, Development And Yield Of Soybean In South Carolina, Mengxuan Hu

All Theses

Planting date plays a significant role in determining soybean growth, development and seed yield. The objectives of this experiment were to evaluate the effects of late planting date, management system, and maturity group on the growth, development and seed yield of maturity group VII and VIII soybean under dry land conditions in the Southeastern coastal plain of the United States. Plant growth and development, seed yield, yield components, and seed oil and protein concentrations were evaluated throughout the season. These experiments were conducted in South Carolina at the Edisto Research and Education Center near Blackville and the Pee Dee Research …


Challenges In Testing Genetically Modified Crops For Potential Increases In Endogenous Allergen Expression For Safety, Rakhi Panda, H. Ariyarathna, Plaimein Amnuaycheewa, Afua O. Tetteh, S. N. Pramod, Steve Taylor, B. K. Ballmer-Weber, Richard E. Goodman Feb 2013

Challenges In Testing Genetically Modified Crops For Potential Increases In Endogenous Allergen Expression For Safety, Rakhi Panda, H. Ariyarathna, Plaimein Amnuaycheewa, Afua O. Tetteh, S. N. Pramod, Steve Taylor, B. K. Ballmer-Weber, Richard E. Goodman

Department of Food Science and Technology: Faculty Publications

Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for …


Evaluation Of Endogenous Allergens For The Safety Evaluation Of Genetically Engineered Food Crops: Review Of Potential Risks, Test Methods, Examples And Relevance, Richard E. Goodman, Rakhi Panda, Harsha Ariyarathna Jan 2013

Evaluation Of Endogenous Allergens For The Safety Evaluation Of Genetically Engineered Food Crops: Review Of Potential Risks, Test Methods, Examples And Relevance, Richard E. Goodman, Rakhi Panda, Harsha Ariyarathna

Department of Food Science and Technology: Faculty Publications

The safety of food produced from genetically engineered (GE) crops is assessed for potential risks of food allergy on the basis of an international consensus guideline outlined by the Codex Alimentarius Commission (2003). The assessment focuses on evaluation of the potential allergenicity of the newly expressed protein(s) as the primary potential risk using a process that markedly limits risks to allergic consumers. However, Codex also recommended evaluating a second concern, potential increases in endogenous allergens of commonly allergenic food crops that might occur due to insertion of the gene. Unfortunately, potential risks and natural variation of endogenous allergens in non-GE …


Snp-Based Genetic Linkage Map Of Soybean Using The Soysnp6k Illumina Infinium Beadchip Genotyping Array, Masum Akond, Shiming Liu, Lauren Schoener, James A. Anderson, Stella K. Kantartzi, Khalid Meksem, Qijian Song, Dechun Wang, Zixiang Wen, David A. Lightfoot, My Abdelmajid Kassem Jan 2013

Snp-Based Genetic Linkage Map Of Soybean Using The Soysnp6k Illumina Infinium Beadchip Genotyping Array, Masum Akond, Shiming Liu, Lauren Schoener, James A. Anderson, Stella K. Kantartzi, Khalid Meksem, Qijian Song, Dechun Wang, Zixiang Wen, David A. Lightfoot, My Abdelmajid Kassem

Articles

This study reports a high density genetic linkage map based on the ‘Maryland 96-5722’ by ‘Spencer’ recombinant inbred line (RIL) population of soybean [Glycine max (L.) Merr.] and constructed exclusively with single nucleotide polymorphism (SNP) markers. The Illumina Infinium SoySNP6K BeadChip genotyping array produced 5,376 SNPs in the mapping population, with a 96.75% success rate. Significant level of goodness-of-fit for each locus was tested based on the observed vs. expected ratio (1:1). Out of 5,376 markers, 1,465 SNPs fit the 1:1 segregation rate having ≤20% missing data plus heterozygosity among the RILs. Among this 1,456 just 657 were polymorphic …


Impacts Of Elevated Co2 Concentration On The Productivity And Surface Energy Budget Of The Soybean And Maize Agroecosystem In The Midwest Usa, Tracy E. Twine, Jarod J. Bryant, Katherine T. Richter, Carl J. Bernacchi, Kelly D. Mcconnaughay, Sherri J. Morris, Andrew D. B. Leakey Jan 2013

Impacts Of Elevated Co2 Concentration On The Productivity And Surface Energy Budget Of The Soybean And Maize Agroecosystem In The Midwest Usa, Tracy E. Twine, Jarod J. Bryant, Katherine T. Richter, Carl J. Bernacchi, Kelly D. Mcconnaughay, Sherri J. Morris, Andrew D. B. Leakey

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

The physiological response of vegetation to increasing atmospheric carbon dioxide concentration ([CO2]) modifies productivity and surface energy and water fluxes. Quantifying this response is required for assessments of future climate change. Many global climate models account for this response; however, significant uncertainty remains in model simulations of this vegetation response and its impacts. Data from in situ field experiments provide evidence that previous modeling studies may have overestimated the increase in productivity at elevated [CO2], and the impact on large-scale water cycling is largely unknown. We parameterized the Agro-IBIS dynamic global vegetation model with observations from …


Morpho-Physiological Parameters Affecting Iron Deficiency Chlorosis In Soybean (Glycine Max L.), Marta W. Vasconcelos, Michael A. Grusak Jan 2013

Morpho-Physiological Parameters Affecting Iron Deficiency Chlorosis In Soybean (Glycine Max L.), Marta W. Vasconcelos, Michael A. Grusak

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

Background and aims Iron deficiency chlorosis (IDC) leads to severe leaf chlorosis, low photosynthetic rates, and yield reductions of several million metric tonnes each year. In order to devise breeding and genetic transformation programs that aim at generating high-yielding and IDC-tolerant soybean lines, it is necessary to better understand the mechanisms that enable tolerant plants to survive under Fe-limiting conditions.

Methods An in silico analysis in the USDA soybean collection allowed the identification of a set of novel efficient and inefficient soybean cultivars which can be used in future studies concerning IDC response. Plants were grown in iron deficient and …


Nutrient Contents, Color, Texture, And Sensory Evaluation Of 12 Arkansas Grown Soybean Cultivars In Canned Products, Quyen Nguyen, Navam Hettiarachchy, Srinivas J. Rayaprolu Jan 2013

Nutrient Contents, Color, Texture, And Sensory Evaluation Of 12 Arkansas Grown Soybean Cultivars In Canned Products, Quyen Nguyen, Navam Hettiarachchy, Srinivas J. Rayaprolu

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Soybean was introduced in the U.S. in the 1800s, and it has been proven to have several health benefits. New cultivars of soybeans with varying hull colors have been developed using plantbreeding technology. Canning is one of the effective processing methods to extend the shelf life of products. However, very little information is available on canned soybeans. This research studied the composition of 12 soybean cultivars including two cultivars with brown seed coat (R08-4014 and R09-349), three cultivars with black seed coat (R07-1927, R07-10396, and R09-345), and seven regular cultivars with yellow seed coat (R05-1772, R05-4969, R07-2001, R08-4005, R08- 4006, …


The Influence Of Different Cover Types On American Robin Nest Success In Organic Agroecosystems, John E. Quinn, Amy I. Oden, James R. Brandle Jan 2013

The Influence Of Different Cover Types On American Robin Nest Success In Organic Agroecosystems, John E. Quinn, Amy I. Oden, James R. Brandle

School of Natural Resources: Faculty Publications

There are many opportunities for biodiversity conservation in organic farm systems. Successful and sustainable conservation efforts in organic systems, however, need to measure appropriate outcomes. In particular, data are needed on the breeding success of associated wildlife species. We measured nesting success of the American Robin (Turdus migratorius) in woodlands embedded within eight organic farms in eastern Nebraska. We modeled daily nest survival rate to identify land use and land cover patterns that optimize conservation of birds in organic farm systems. The percentage of a crop in the fields adjacent to linear woodlands best predicted daily survival rate. …


Biofield And Fungicide Seed Treatment Influences On Soybean Productivity,Seed Quality And Weed Community, Mahendra Kumar Trivedi Jan 2013

Biofield And Fungicide Seed Treatment Influences On Soybean Productivity,Seed Quality And Weed Community, Mahendra Kumar Trivedi

Mahendra Kumar Trivedi

Soybean production in Iowa USA is among the most productive for raínfed regions in the world. Despite generally having excellent soils, growing season temperatures and rainfall, soybean yields are decreased by weed interference and inadequate available soil water at key stages of crop development. A field study was conducted at two locations in lowa in 2012 to determine if seed-applied fungicide or biofield treatments influenced weed community, soil volumetric water concentration and soybean yield and quality. Application of biofield treatment resulted in lower density of tall waterhemp density, greater soybean stand density at R8 stage and greater seed pod-1 compared …


The Influence Of Different Cover Types On American Robin Nest Success In Organic Agroecosystems, John E. Quinn, Amy Oden, James R. Brandle Jan 2013

The Influence Of Different Cover Types On American Robin Nest Success In Organic Agroecosystems, John E. Quinn, Amy Oden, James R. Brandle

Biology Publications

There are many opportunities for biodiversity conservation in organic farm systems. Successful and sustainable conservation efforts in organic systems, however, need to measure appropriate outcomes. In particular, data are needed on the breeding success of associated wildlife species. We measured nesting success of the American Robin (Turdus migratorius) in woodlands embedded within eight organic farms in eastern Nebraska. We modeled daily nest survival rate to identify land use and land cover patterns that optimize conservation of birds in organic farm systems. The percentage of a crop in the fields adjacent to linear woodlands best predicted daily survival rate. …


The Influence Of Plants On Atmospheric Methane In An Agriculture-Dominated Landscape, Xin Zhang, Xuhui Lee, Timothy J. Griffis, John M. Baker, Matt D. Erickson, Ning Hu, Wei Xiao Jan 2013

The Influence Of Plants On Atmospheric Methane In An Agriculture-Dominated Landscape, Xin Zhang, Xuhui Lee, Timothy J. Griffis, John M. Baker, Matt D. Erickson, Ning Hu, Wei Xiao

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

The primary objective of this study was to clarify the influence of crop plants on atmospheric methane (CH4) in an agriculture-dominated landscape in the Upper Midwest of the United States. Measurements were carried out at two contrasting scales. At the plant scale, CH4 fluxes from soybean and corn plants were measured with a laser-based plant chamber system. At the landscape scale, the land surface flux was estimated with a modified Bowen ratio technique using measurements made on a tall tower. The chamber data revealed a diurnal pattern for the plant CH4 flux: it was positive (an …


Thirty-Year Tillage Effects On Crop Yield And Soil Fertility Indicators, Douglas Karlen, John L. Kovar, Cynthia A. Cambardella, Thomas S. Colvin Jan 2013

Thirty-Year Tillage Effects On Crop Yield And Soil Fertility Indicators, Douglas Karlen, John L. Kovar, Cynthia A. Cambardella, Thomas S. Colvin

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

Long-term studies are crucial for quantifying tillage effects on productivity and soil fertility. Moldboard plow, chisel plow, spring disk, ridge-tillage, and no-tillage systems were evaluated after 32 years of a corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotation and 27 years of continuous corn in central Iowa, U.S.A. Productivity was quantified using yield, while soil fertility status was evaluated by collecting four, 5-cm diameter soil cores to a depth of 0.9 m from each treatment, dividing them into four depth increments (0–15-, 15–30-, 30–60-, and 60–90-cm), analyzing them for bulk density (BD), NO3-N, …


Soil Quality Response To Long-Term Tillage And Crop Rotation Practices, Douglas Karlen, Cynthia A. Cambardella, John L. Kovar, Thomas S. Colvin Jan 2013

Soil Quality Response To Long-Term Tillage And Crop Rotation Practices, Douglas Karlen, Cynthia A. Cambardella, John L. Kovar, Thomas S. Colvin

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

Soil quality is influenced by inherent and anthropogenic factors. This study was conducted to provide multiple groups guidance on how to achieve and maintain improved soil quality/health. Our hypothesis was that tillage intensity was the primary anthropogenic factor degrading soil quality, and our objective was to prove that hypothesis through an intensive 2005 sampling of a central Iowa, USA field study. Chisel plow, disk tillage, moldboard plow, ridge-till and no-till treatments, used for 31 years in a twoyear, corn (Zea mays L.)/soybean [Glycine max (L.) Merr.] (C/S) rotation or for 26 years of continuous corn (CC) production, were …


Development And Evaluation Of Ordinary Least Squares Regression Models For Predicting Irrigated And Rainfed Maize And Soybean Yields, Vivek Sharma, Daran R. Rudnick, Suat Irmak Jan 2013

Development And Evaluation Of Ordinary Least Squares Regression Models For Predicting Irrigated And Rainfed Maize And Soybean Yields, Vivek Sharma, Daran R. Rudnick, Suat Irmak

Biological Systems Engineering: Papers and Publications

Understanding the relationships between climatic variables and soil physical and chemical properties with crop yields on large scales is critical for evaluating crop productivity to make better assessments of local and regional food security, policy, land and water resource allocation, and management decisions. In this study, ordinary least squares(OLS) regression models were developed to predict irrigated and rainfed maize and soybean yields at the county level as a

function of explanatory variables [precipitation (P), actual crop evapotranspiration (ETa), organic matter content (OMC), cation exchange capacity (CEC), clay content (CC), and available soil water capacity (ASW)] of the dominant soil type …


Transferability Of Jarvis-Type Models Developed And Re-Parameterized For Maize To Estimate Stomatal Resistance Of Soybean: Analyses On Model Calibration, Validation, Performance, Sensitivity, And Elasticity, Denis Mutiibwa, Suat Irmak Jan 2013

Transferability Of Jarvis-Type Models Developed And Re-Parameterized For Maize To Estimate Stomatal Resistance Of Soybean: Analyses On Model Calibration, Validation, Performance, Sensitivity, And Elasticity, Denis Mutiibwa, Suat Irmak

Biological Systems Engineering: Papers and Publications

In a previous study by the same authors, a new modified Jarvis model (NMJ-model) was developed, calibrated, and validated to estimate stomatal resistance (rs) for maize canopy on an hourly time step. The NMJ-model’s unique subfunctions, different from the original Jarvis model (J-model), include a photosynthetic photon flux density

(PPFD)-rs response subfunction developed from field measurements and a new physical term, Aexp(1/LAI), where A is the minimum stomatal resistance and LAI is the green leaf area index, to account for the influence of canopy development on rs, especially during partial canopy stage in the early season and …


Ec13-872 Nebraska 2013 Crop Budgets, Robert N. Klein, Roger K. Wilson Jan 2013

Ec13-872 Nebraska 2013 Crop Budgets, Robert N. Klein, Roger K. Wilson

University of Nebraska-Lincoln Extension: Historical Materials

This publication contains crop production budgets for 13 crops and 51 cropping systems, as well as tables of power, machinery, labor, and input costs used to develop these budgets. Each budget consists of five sections:

  • Heading
  • List of representative field operations
  • List of materials and services used
  • Operations and interest tabulations
  • Overhead costs including real estate taxes and opportunity­ charges

The budgets are presented in a worksheet format with a “Your Estimate’’ column for recording cost modifications.