Agronomy and Crop Sciences Commons^™

Irrigated Soybean Response To Granular Fertilizer Potassium Application Timing, Nathan A. Slaton, Trenton L. Roberts, W. Jeremy Ross, Tyler L. Richmond

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Amelioration of K deficiency during the growing season requires knowledge of critical tissue concentrations and crop yield response to fertilization time. Our objectives were to characterize the yield and uptake responses of K-deficient irrigated soybean [Glycine max (L.) Merr.] to in-season fertilizer-K application time and rate, evaluate fertilizer-potassium-recovery efficiency (FKRE), and evaluate how leaflet-K concentration responds to K-fertilization time. Six trials were established on silt loam soils. Muriate of potash was applied pre-plant and compared to an equivalent K rate applied post-emergence on six or seven dates. Grain yield, trifoliolate-K concentration, and K uptake were measured. Relative soybean yields …

Soybean Growth And Incidence Of Soil-Borne Fungi As Influenced By Metribuzin, Grant L. Priess, Jason K. Norsworthy, Trenton L. Roberts, Terry Neil Spurlock, Edward E. Gbur Jr.

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Soybean injury following an application of metribuzin soon after planting can occur under cool, wet conditions, especially for varieties that lack a high level of tolerance to the herbicide. Field experiments were conducted in 2017 and 2018 in Fayetteville, AR, to evaluate the impacts of metribuzin at 0, 280, 560, 840, and 1,120 g ai ha⁻¹ on soybean growth and incidence of soil-borne fungi. Three classes of metribuzin tolerance (sensitive, moderately tolerant, and tolerant) were evaluated based on a previous screen. In both years, visible injury to soybean was impacted by varietal tolerance and metribuzin rate. As metribuzin rate …

Corn And Soybean Response To Wastewater-Recovered And Other Common Phosphorus Fertilizers, Shane Ylagan, Kristofor R. Brye, Lauren Greenlee

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Recycling P from wastewaters may provide a sustainable source of P that could also protect surface water quality from P enrichment. Struvite (MgNH₄PO₄·6H₂O) is a material that can be created from P-containing wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green, CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple superphosphate (TSP) on corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] response in a 79-d greenhouse …

Effects Of Char On Nitrogen Management In Agricultural Soils Of Semi-Arid Western Nebraska, Dinesh Panday

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

Soils in western Nebraska are characterized by low soil organic C due to semi-arid environment in the region and further aggravated by disruption of soil aggregates and rapid C decomposition from intensive tillage, erosion, and frequent droughts. Proper management of soil C may improve soil properties, reduce N losses, and subsequently improve crop yields in this low C soil and low moisture condition. This dissertation focuses on C-rich coal char (henceforth “char”) as a potential strategy to overcome the existing problem of low C in semi-arid region. Char is an industrial by-product, resulting from inefficient coal burning during sugar beet …

Profit-Maximizing Potassium Fertilizer Recommendations For Soybean, Michael P. Popp, Nathan A. Slaton, Trenton L. Roberts

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Potassium (K) fertilizer has important yield and cost ramifications in soybean [Glycine max (L.) Merr.] production. Rate recommendations are often based on expected yield response as predicted by a soil test. To that end, soybean response to K application rate studies were analyzed using 86 site-years from 2004 to 2019. We estimated a generic yield response curve across soybean cultivar and soil texture to allow calculation of profit-maximizing K rates for producers in the mid-southern United States that also consider crop value and fertilizer cost. Further, we compared profit-maximizing fertilizer-K rates with those currently recommended. Using a spreadsheet-based decision …

Fate And Transport Of Phosphorus-Containing Land-Applied Swine Slurry In A Karst Watershed, A. N. Sharpley, M. B. Daniels, K. R. Brye, K. Vandevender, J. Burke, L G. Berry, P. Webb

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Phosphorus distribution in pasture soils underlain with karst geology was determined on a 0.10-ha grid in 2014, 2016, and 2018. Two fields (Fields 1 and 12) received swine slurry from a concentrated animal feeding operation, whereas another (Field 5) received mineral fertilizer. All fields were grazed by cattle and periodically hayed. Mean Mehlich-3 extractable P in the top 10 cm increased (p ≤ .05 level) for Fields 1 (59–91 mg kg⁻¹) and 12 (63–122 mg kg⁻¹) between 2014 and 2018, with little change for Field 5 (45–47 mg kg⁻¹). Over the 5-yr monitoring …

Influence Of Cover Crop Management Practices On Rainfed Corn Production In Semi-Arid Western Nebraska, Alexandre Tonon Rosa

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

With the increased cover crop (CC) popularity, producers of semi-arid regions of western Nebraska are questioning whether they could successfully incorporate CC into their rainfed winter wheat (Triticum aestivum L.)-corn (Zea mays L.)-fallow rotations. The major concern is that CCs may deplete soil water affecting the subsequent crop. Therefore, three studies were established under rainfed conditions of western Nebraska to access the effects of CCs on soil water, soil compaction, nutrient cycling, weed demographics, residue coverage, and subsequent corn yield. The first study evaluated the influence of CC planting and termination times prior to corn establishment. Late termination …

Description Of Baetao-Manteiga 41 And ‘Yunguilla’ Superior Andean Common Beans For Tanzanian Production Environments, S. Nchimbi Msolla, Phillip N. Miklas, D. Fourie, M. Kilango, T. Porch

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

An international effort was initiated with the evaluation of a diverse set of largeseeded Andean common beans (Phaseolus vulgaris L.), the Andean Diversity Panel, in sub-Saharan Africa. Several entries in the panel have been selected for extensive characterization on the basis of high performance acrossmultiple location × year trials in Tanzania—conducted both on station and on farm. Baetao- Manteiga 41, tested asADP-190, has a commercialKablanketi (light purple speckled) seed type, and ‘Yunguilla’, tested as ADP-447, has a commercial Calima (red mottled) seed type. Both lines exhibited yield stability, vigorous growth under low fertility conditions, angular leaf spot resistance, andmoderate …

Perioperative And Oncological Outcomes Following Minimally Invasive Versus Open Pancreaticoduodenectomy For Pancreatic Duct Adenocarcinoma, Rui Sun, Jiawen Yu, Yifan Zhang

Department of Agronomy and Horticulture: Faculty Publications

Background The outcomes of minimally invasive pancreaticoduodenectomy have not been adequately compared with those of open pancreaticoduodenectomy in patients with pancreatic ductal adenocarcinoma. We performed a meta‐analysis to compare the perioperative and oncological outcomes of these two pancreaticoduodenectomy procedures specifically in patients with pancreatic ductal adenocarcinoma.

Methods Before this study was initiated, a specific protocol was designed and has been registered in PROSEPRO (ID: CRD42020149438). Using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, PubMed, EMBASE, Web of Science, Cochrane Central Register, and ClinicalTrials.gov databases were systematically searched for studies published between January 1994 and October 2019. …

Impact Of Covid-19 On Arkansas Field Crop Farms, A. Durand-Murat, S. Stiles, B. Watkins, C. R. Stark Jr.

AAES Research Reports and Research Bulletins

The coronavirus (COVID-19) pandemic is disrupting the global economy in unprecedented ways, and the agricultural sector is no exception. Prices of most commodities decreased since the pandemic began, which are affecting farm revenues and production costs. We assess the impact of COVID-19 on Arkansas field crop farms using the Representative Farm models, calibrated to the latest baseline published by the Food and Agricultural Policy Research Institute. The results show that COVID-19 decreases the net cash farm incomes of all five farms, increases the probability of having a negative net cash farm income, and increases the cost of commodity programs. Payments …

Evaluating Opportunities For Integrated Crop Livestock Systems In Eastern Nebraska, Elizabeth Kay Christenson

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

Current agricultural systems focused on production of few commodities are facing production, economic, and environmental challenges. To address these challenges, Integrated Crop Livestock Systems (ICLS) have emerged through three primary methods 1) perennial grasslands for grazing and/or hay production, 2) crop residue grazing, and 3) cover crop grazing. To evaluate potential of ICLS mitigating current challenges, a field scale model ICLS was developed in 2015. The ICLS includes 4-ha each of ‘Newell’ smooth bromegrass (Bromus inermis L.), ‘Liberty’ switchgrass (Panicum virgatum L.), and ‘Shawnee’ switchgrass. The ICLS also included 8-ha of continuous corn (Zea mays L.). In …

Soybean Maturity Group And Planting Date Influence Grain Yield And Nitrogen Dynamics, Carrie C. Ortel, Trenton L. Roberts, Kyle A. Hoegenauer, Larry C. Purcell, Nathan A. Slaton, Edward E. Gbur

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Manipulation of soybean [Glycine max (L.) Merr.] maturity group (MG) and planting date will increase the yield of a soybean crop while simultaneously influencing the potential soil-nitrogen (N) credits. Variations in N returned to the soil by soybean can significantly affect the amount of fertilizer-N needed for the subsequent crop. Four soybean MGs (3.5, 4.7, 5.4, and 5.6) were evaluated at optimal and late planting dates in Arkansas. Grain yield was significantly different among MGs in 2016 (P = .0012) and 2017 (P = .0004), with the 4.7 MG consistently yielding the highest at 3,232 kg ha(-1). Plant total aboveground …

Soil-Nitrogen, Potentially Mineralizable-Nitrogen, And Field Condition Information Marginally Improves Corn Nitrogen Management, Jason Clark, Fabián G. Fernández, Kristen S. Veum, James J. Camberato, Paul R. Carter, Richard Ferguson, David W. Franzen, Daniel E. Kaiser, Newell R. Kitchen, Carrie A.M. Laboski, Emerson Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Anaerobic potentially mineralizable nitrogen (PMN) combined with preplant nitrate test (PPNT) or pre-sidedress nitrate test (PSNT) may improve corn (Zea mays L.) N management. Forty-nine corn N response studies were conducted across the U.S. Midwest to evaluate the capacity of PPNT and PSNT to predict grain yield, N uptake, and economic optimal N rate (EONR) when adjusted by soil sampling depth, soil texture, temperature, PMN, and initial NH₄–N from PMN analysis. Pre-plant soil samples were obtained for PPNT (0- to 30-, 30- to 60-, 60- to 90-cm depths) and PMN (0- to 30-cm depth) before corn planting …

Performance Evaluation Of Four Arkansas Table Grape Cultivars Grown On Three Trellis Systems Under High Tunnels At Two Locations In Arkansas., Jose Hernandez

Graduate Theses and Dissertations

Grapevines (Vitis vinifera L.) are one of the most important horticultural crops world-wide. In the southern U.S. region, hot and humid climate accompanied by high pest pressure requires high levels of labor and pesticide inputs, making open field table grape production unsustainable. Previous research at University of Arkansas has demonstrated that table grape production under high tunnels (HTs) is a viable option to overcome biotic and abiotic challenges in the region. This project evaluated two HTs established in Arkansas. In the spring of 2014, at Fayetteville, three table grape cultivars (Faith, Gratitude, and Jupiter) were established in an 8 x …

Projected Surface Water For Fruit And Vegetable Irrigation Under A Changing Climate In The Us, Marty Matlock, Greg Thoma, Kieu Ngoc Le, Eric Cummings, Zach Morgan, Andrew Shaw

Water Systems

Increasing greenhouse gas concentrations in the atmosphere, resulting in climate impacts, are raising concerns over the hydrologic cycle and its effects upon agricultural productivity. If rainfall patterns change, meeting an increased demand for fruits and vegetables will pose a challenge for domestic production regions in the United States (U.S.). Information on potential water supply scarcity in the current production regions provides decision makers with critical information for risk mitigation for future production. We used a hydrologic balance-based model of historic and future water availability to evaluate risk of available irrigation water to support major fruit and vegetable production the US. …

Effects Of Pyric Herbivory On Prairie-Chicken (Tympanuchus Spp) Habitat, Heath D. Starns, Samuel D. Fuhlendorf, Robert D. Elmore, Dirac Twidwell, Eric T. Thacker, Torre J. Hovick, Barney Luttbeg

Department of Agronomy and Horticulture: Faculty Publications

The reduction and simplification of grasslands has led to the decline of numerous species of grassland fauna, particularly grassland-obligate birds. Prairie-chickens (Tympanuchus spp.) are an example of obligate grassland birds that have declined throughout most of their distribution and are species of conservation concern. Pyric herbivory has been suggested as a land management strategy for enhancing prairie-chicken habitat and stabilizing declining population trends. We assessed differences in vegetation structure created by pyric herbivory compared to fire-only treatments to determine whether pyric herbivory increased habitat heterogeneity for prairie-chickens, spatially or temporally. Our study was performed at four sites in the southern …

Soil Chemical Properties After 12 Years Of Tillage And Crop Rotation, Maysoon M. Mikha, Gary Hergert, Xin Qiao, Bijesh Maharjan

Panhandle Research and Extension Center

Crop rotation in combinationwith tillage can improve productivity, enhance economical return, and reduce soil erosion. The objective of this study was to evaluate the impact of moldboard plow (MP), strip tillage (ST), no-tillage (NT), and crop rotations on: (1) crop yield; (2) soil chemical properties; and (3) particulate organic matter (POM). The study was initiated in 2007 at the University of Nebraska-Lincoln Panhandle Research and Extension Center near Scottsbluff, NE. Crops in rotation were corn (C; Zea mays L.) and dry bean (DB; Phaseolus vulgaris L.) organized in a 3-yr rotation (C–DB–C) and a 4-yr rotation with the addition of …

Utilizing Annual Forage Crops In Rotations, John Hewlett, Jay Parsons, Jeff Tranel

Extension Farm and Ranch Management News

First paragraph

Approximately 60 million acres of forage are harvested annually in the United States, according to the National Agricultural Statistical Service (NASS). With lower commodity grain and oilseed prices along with high pasture rental rates and/or difficulty finding range and pasture to rent, some producers are considering ways to incorporate more forages into their crop rotations.

Cover Cropping In Soybean-Corn Rotation System: Economic, Agronomic, And Soil Fertility Impact, Jose Rodolfo Mite

LSU Doctoral Dissertations

Planting winter-annual cover crops prevent soil erosion, reduces water runoff, and improves soil structure and soil quality. This research was conducted from 2017 to 2019 to evaluate the nutrient turnover of different species of cover crops in soils under different row crop production systems in Northeast and Central Louisiana. In Northeast Louisiana (Site 1, 2, and 3), treatments (cover crops and no cover crop) were arranged in a strip trial with three replications. At the Ben Hur Research Station, the treatments included three planting dates (September, October, and November) with [7 kg ha^-1 of phosphorus (P) and potassium (K)] …

Public Relations Of Cal Poly Avocado Rootstock Trial, Angel Daniel Carrillo

Agricultural Education and Communication

Avocados have been one of California’s specialty crops for quite some time now. The industry has been motivating growers to implement the best management practices to ensure stable and increased production as much as they possibly can. California is the leading state in the country for avocado production. In 2019, California alone produced 109 tons of avocados (US Department of Agriculture, 2020). Unfortunately, root rot has made it a challenge to do so.

Root rot is a disease derived from the Phytophthora cinnamomi pathogen. This is an issue for avocado production worldwide. In efforts to find a method of decreasing …

Production And Selection Of Quality Protein Popcorn Hybrids Using A Novel Ranking System And Combining Ability Estimates, Leandra Parsons, Ying Ren, Abou Yobi, Preston Hurst, Ruthie Angelovici, Oscar Rodriguez, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Popcorn varieties are agronomically sub-optimal and genetically limited compared to other maize subspecies. To increase genetic diversity and improve popcorn agronomics, dent germplasm has been introduced to popcorn with limited success and generally, major loss of popping. Between 2013 and 2018, 12 Quality Protein Popcorn (QPP) inbreds containing Quality Protein Maize (QPM) and popcorn germplasm were produced that maintained popping while carrying the opaque-2 allele conferring elevated kernel lysine. This is an opportune trait in the growing market for healthier snacks and a model for mining QPM traits into popcorn. We crossed QPP inbreds to explore the effects of heterosis …

Genomic Prediction Enhanced Sparse Testing For Multi-Environment Trials, Diego Jarquin, Reka Howard, José Crossa, Yoseph Beyene, Manje Gowda, Johannes W.R. Martini, Giovanny Covarrubias Pazaran, Juan Burgueño, Angela Pacheco, Martin Grondona, Valentin Wimmer, Boddupalli M. Prasanna

Department of Agronomy and Horticulture: Faculty Publications

“Sparse testing” refers to reduced multi-environment breeding trials in which not all genotypes of interest are grown in each environment. Using genomic-enabled prediction and a model embracing genotype · environment interaction (GE), the non-observed genotype-in-environment combinations can be predicted. Consequently, the overall costs can be reduced and the testing capacities can be increased. The accuracy of predicting the unobserved data depends on different factors including (1) how many genotypes overlap between environments, (2) in how many environments each genotype is grown, and (3) which prediction method is used. In this research, we studied the predictive ability obtained when using a …

Effects Of Tank Contamination And Impact Of Drift-Reducing Agents On Weed Control In Response To Dicamba Applications, Milos Zaric

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

Availability of dicamba-tolerant (DT) crops from 2017 provided farmers with additional herbicides for weed control management in row crops. However, the technology alike this one has concerns regarding dicamba off-target movement (OTM) causing undesirable effects on sensitive vegetation. Even though dicamba has high water solubility OTM that has often been overlooked when it comes to unintended crop exposure is dicamba tank contamination. Considering the complexity of spraying equipment soybean response may be expected even when small amounts of residues are left in the spray equipment. Typically, the same field spray equipment is used to perform herbicide application through growing season …

Soybean Response To Dicamba Exposure In Furrow Irrigation, Erin Grantz, Jung Ae Lee, Cammy Willett, Jason K. Norsworthy

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Sensitive crop exposure to residual dicamba in irrigation is a potential hazard in regions with overlapping use of transgenic dicamba-resistant crops and on-farm water storage-tailwater recovery (OFWS-TWR) systems. This field study examined non-dicamba-resistant soybean [Glycine max (L.) Merr.] for response to a dicamba dose gradient (7.6-630 g ae ha(-1)) in a furrow irrigation system. In a second study, growth stage and application timing effects were explored, with dicamba applied at 160 g ae ha(-1) in entirety to V3 or R1 soybean or split across exposure events. Plant injury 14 and 28 d after treatment (DAT) increased with dose, with significant …

Irrigation, Carbon Amelioration, Nitrogen, And Stover Removal Effects On Continuous Corn, Marty Schmer, Virginia L. Jin, Richard B. Ferguson, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Corn (Zea mays L.) residue or stover is harvested as supplemental feed for livestock and is a potential feedstock for cellulosic biofuels. Limited information is available on corn stover removal effects on grain yield under different irrigation rates, nitrogen (N) fertilizer rates, and practices to maintain soil carbon (C) and minimize soil erosion. We evaluated potential interactions between irrigation rate (full or limited), C amelioration practices (cover crop, surface-applied manure, or no amelioration practice), fertilizer N management (125 or 200 kg N ha⁻¹), and stover removal (residue removal or no residue removal), on no-till continuous corn …

Weed Control Efficacy Of Bio-Based Sprayable Mulch Films In Specialty Crop Systems, Eliott Gloeb

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

A sprayable bio-based mulch film (biofilm) could present a more sustainable weed management tool for specialty crop producers than conventional plastic mulch films while also offering flexibility in application patterns and timing. From 2017 to 2019, six greenhouse trials and four field trials were conducted at the University of Nebraska-Lincoln to study the effects of biofilm application on weed suppression and crop yields. Multiple application rates (0.81 L/m² - 9.78 L/m²) and application times (prior to weed emergence and post weed emergence) were tested. Corn starch, glycerol, keratin hydrolysate, corn gluten meal, corn zein, and isolated soy …

Characterizing Variation In Nitrogen Use Efficiency In Wheat Genotypes Using Proximal Canopy Sensing For Sustainable Wheat Production, Mohammed A. Naser, Raj Khosla, Louis Longchamps, Subash Dahal

Department of Agronomy and Horticulture: Faculty Publications

Global nitrogen use efficiency (NUE) for cereal production is marginal and is estimated to be about 33%. Remote sensing tools have tremendous potential for improving NUE in crops through efficient nitrogen management as well as the identification of high-NUE genotypes. The objectives of this study were (i) to identify and quantify the variation in NUE across 24 winter wheat genotypes (Triticum aestivum L.) and (ii) to determine if the normalized difference vegetation index (NDVI) could characterize the variability in NUE across wheat genotypes. This study was conducted in 2010 and 2011 in the semi-arid climate of Northeastern Colorado across dryland …

Genome Wide Association Study Reveals Plant Loci Controlling Heritability Of The Rhizosphere Microbiome, Siwen Deng, Daniel F. Caddell, Gen Xu, Lindsay Dahlen, Lorenzo Washington, Jinliang Yang, Devin Coleman-Derr

Department of Agronomy and Horticulture: Faculty Publications

Host genetics has recently been shown to be a driver of plant microbiome composition. However, identifying the underlying genetic loci controlling microbial selection remains challenging. Genome-wide association studies (GWAS) represent a potentially powerful, unbiased method to identify microbes sensitive to the host genotype and to connect them with the genetic loci that influence their colonization. Here, we conducted a population-level microbiome analysis of the rhizospheres of 200 sorghum genotypes. Using 16S rRNA amplicon sequencing, we identify rhizosphere-associated bacteria exhibiting heritable associations with plant genotype, and identify significant overlap between these lineages and heritable taxa recently identified in maize. Furthermore, we …

Assessing Approaches For Stratifying Producer Fields Based On Biophysical Attributes For Regional Yield-Gap Analysis, Spyridon Mourtzinis, Patricio Grassini, Juan I. Rattalino Edreira, José F. Andrade, Peter M. Kyveryga, Shawn P. Conley

Department of Agronomy and Horticulture: Faculty Publications

Large databases containing producer field-level yield and management records can be used to identify causes of yield gaps. A relevant question is how to account for the diverse biophysical background (i.e., climate and soil) across fields and years, which can confound the effect of a given management practice on yield. Here we evaluated two approaches to group producer fields based on biophysical attributes: (i) a technology extrapolation domain spatial framework (‘TEDs’) that delineates regions with similar (long-term average) annual weather and soil water storage capacity and (ii) clusters based on field-specific soil properties and weather during each crop …

The Economics Of On-Farm Rice Drying In Arkansas, Clayton Parker

Agricultural Economics and Agribusiness Undergraduate Honors Theses

Globally, rice producers are faced with the temporal problem of deciding the optimal time to being rice harvest. When harvested, paddy rice is typically at a moisture content (HMC) between 15 and 22%. Upon delivery, the rice is subsequently dried by the mill to a moisture content (MC) of 12.5%. Riceland Foods Inc., the largest miller of rice in the world, uses a stair-step pricing model to charge farmers to dry in price/unit as the MC of grain decreases from a range of +22% to 13.5%. This study estimates an alternative linear relationship in the stair-step model to determine MC …