Agronomy and Crop Sciences Commons^™

Optimising The Identification Of Causal Variants Across Varying Genetic Architectures In Crops, Chenyong Miao, Jinliang Yang, James C. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Association studies use statistical links between genetic markers and the phenotype variation across many individuals to identify genes controlling variation in the target phenotype. However, this approach, particularly conducted on a genome-wide scale (GWAS), has limited power to identify the genes responsible for variation in traits controlled by complex genetic architectures. In this study, we employ real-world genotype datasets from four crop species with distinct minor allele frequency distributions, population structures and linkage disequilibrium patterns. We demonstrate that different GWAS statistical approaches provide favourable trade-offs between power and accuracy for traits controlled by different types of genetic architectures. FarmCPU provides …

Transcriptional Reprogramming Of Legume Genomes: Perspective And Challenges Associated With Single-Cell And Single Cell-Type Approaches During Nodule Development, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Transcriptomic approaches revealed thousands of genes differentially or specifically expressed during nodulation, a biological process resulting from the symbiosis between leguminous plant roots and rhizobia, atmospheric nitrogen-fixing symbiotic bacteria. Ultimately, nodulation will lead to the development of a new root organ, the nodule. Through functional genomic studies, plant transcriptomes have been used by scientists to reveal plant genes potentially controlling nodulation. However, it is important to acknowledge that the physiology, transcriptomic programs, and biochemical properties of the plant cells involved in nodulation are continuously regulated. They also differ between the different cell-types composing the nodules. To generate a more accurate …

First Case Of Glufosinate-Resistant Rigid Ryegrass (Lolium Rigidum Gaud.) In Greece, Ilias S. Travlos, Nikolina Cheimona, Rafael De Prado, Amit J. Jhala, Demosthenis Chachalis, Eleni Tani

Department of Agronomy and Horticulture: Faculty Publications

Repeated applications of the same herbicide(s), which are characterized by the same mode of action, increase selection pressure, which in turn favours the evolution of herbicide-resistant weeds. Glufosinate is a broad-spectrum non-selective herbicide being used for weed control for many years around the world. Rigid ryegrass (Lolium rigidum Gaud.) is an economically important grass weed in Greece. Recent complaints by growers about control failure of rigid ryegrass with glufosinate require further investigation and have been the basis of this study. The objectives of this study were to confirm the existence of glufosinate-resistant L. rigidum in Greece and evaluate the …

Empowerment And Tech Adoption: Introducing The Treadle Pump Triggers Farmers’ Innovation In Eastern Ethiopia, Shimelis Beyene, Teshome H. Regassa, Belaineh Legesse, Martha Mamo, Tsegaye Tadesse

Department of Agronomy and Horticulture: Faculty Publications

In 2013, thirty-eight treadle pumps (TPs) were installed as low-cost technology introduction for small-scale irrigation in eastern Ethiopia. This pilot project also trained six farmers on tube well excavation, as well as the installation and maintenance of pumps. In June 2015, researchers visited nine of the thirty-eight TP villages and found only two TPs functioning as originally installed. The rest were replaced with a new technology developed by the trained farmers. Farmers, empowered by training, gained more control in developing technology options tailored to local needs and conditions of their communities. Adopters of the new technology stated that the limited …

Beyond The Plot: Technology Extrapolation Domains For Scaling Out Agronomic Science, Juan I. Rattalino Edreira, Kenneth G. Cassman, Zvi Hochman, Martin K. Van Ittersum, Lenny Van Bussel, Lieven Claessens, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Ensuring an adequate food supply in systems that protect environmental quality and conserve natural resources requires productive and resource-efficient cropping systems on existing farmland.Meeting this challenge will be difficult without a robust spatial framework that facilitates rapid evaluation and scaling-out of currently available and emerging technologies. Here we develop a global spatial framework to delineate ‘technology extrapolation domains’ based on key climate and soil factors that govern crop yields and yield stability in rainfed crop production. The proposed framework adequately represents the spatial pattern of crop yields and stability when evaluated over the data-rich US Corn Belt. It also facilitates …

Is Conservation Agriculture A Potential Option For Cereal-Based Sustainable Farming System In The Eastern Indo-Gangetic Plains Of Nepal?, Dipendra Pokharel, Raj Kant Jha, Thakur Prasad Tiwari, Mahesh Kumar Gathala, Hari Krishna Shrestha, Dinesh Panday

Department of Agronomy and Horticulture: Faculty Publications

A decline in land and water productivity, increase in the cost of cultivation, and labor-intensive practices are affecting the cereal-based farming system in Nepal, particularly in the Indo-Gangetic Plains (IGP). Conservation agriculture (CA) practices have been found to be the climate-, energy-, and labor-smart and sustainable agricultural production technologies. Sustainable and Resilient Farming System Intensification (SRFSI) has been working since 2014 in response to the sustainability of the cereal-based (rice–wheat and rice–maize) farming in Sunsari and Dhanusha districts of Nepal. This study was conducted to assess the adoption and scaling up of CA in addition to input usage, production, net …

Impact Of Drought On Chemical Composition And Sugar Yields From Dilute-Acid Pretreatment And Enzymatic Hydrolysis Of Miscanthus, A Tall Fescue Mixture, And Switchgrass, Amber Hoover, Rachel Emerson, Allison Ray, Daniel Stevens, Sabrina Morgan, Marnie Cortez, Robert Kallenbach, Matthew Sousek, Rodney Farris, Dayna Daubaras

Department of Agronomy and Horticulture: Faculty Publications

Environmental factors like drought impact the quality of biomass entering a bioconversion process. Drought often reduces the sugar content in lignocellulosic biomass, which could have economic impacts, particularly when compounded with losses in dry biomass yield; however, the effects on conversion efficiency are not completely understood. This study investigated how drought may impact biomass composition and sugar yields from dilute-acid pretreatment and enzymatic hydrolysis of Miscanthus, a tall fescue mixture, and switchgrass from Nebraska, Missouri, and Oklahoma, respectively, grown as part of Regional Feedstock Partnership field trials. Samples were grown and harvested in 2010 during non-drought conditions and in …

Impaired Phloem Loading In Zmsweet13a,B,C Sucrose Transporter Triple Knock-Out Mutants In Zea Mays, Margaret Bezrutczyk, Thomas Hartwig, Marc Horschman, Si Nian Char, Jinliang Yang, Bing Yang, Wolf B. Frommer, Davide Sosso

Department of Agronomy and Horticulture: Faculty Publications

Crop yield is critical for human nutrition, yet the underlying machinery that ultimately determines yield potential is still not understood. Crop productivity under ideal conditions is determined by the efficiency with which plants intercept light, convert it into chemical energy, translocate photosynthates and convert these to storage products in harvestable organs (Zhu et al., 2010). In many crops, sucrose is the primary form for translocation inside the conduit (i.e. the phloem). A combination of SWEETmediated efflux from phloem parenchyma and subsequent secondary active sucrose import by SUT sucrose/H+ symporters is thought to create the driving force for pressure gradient-driven …

Tetracycline And Sulfonamide Antibiotic Resistance Genes In Soils From Nebraska Organic Farming Operations, Marylynn Cadena, Lisa M. Durso, Daniel N. Miller, Heidi M. Waldrip, B. L. Castleberry, Rhae A. Drijber, Charles S. Wortmann

Department of Agronomy and Horticulture: Faculty Publications

There is widespread agreement that agricultural antibiotic resistance should be reduced, however, it is unclear from the available literature what an appropriate target for reduction would be. Organic farms provide a unique opportunity to disentangle questions of agricultural antibiotic drug use from questions of antibiotic resistance in the soil. In this study, soil was collected from 12 certified organic farms in Nebraska, evaluated for the presence of tetracycline and sulfonamide resistance genes (n = 15 targets), and correlated to soil physical, chemical, and biological parameters. Tetracycline and sulfonamide antibiotic resistance genes (ARGs) were found in soils from all 12 …

Sifting And Winnowing: Analysis Of Farmer Field Data For Soybean In The Us North-Central Region, Spyridon Mourtzinis, Juan I. Rattalino Edreira, Patricio Grassini, Adam C. Roth, Shaun N. Casteel, Ignacio A. Ciampitti, Hans J. Kandel, Peter M. Kyveryga, Mark A. Licht, Laura E. Lindsey, Daren S. Mueller, Emerson D. Nafziger, Seth L. Naeve, Jordan Stanley, Michael J. Staton, Shawn P. Conley

Department of Agronomy and Horticulture: Faculty Publications

Field trials are commonly used to estimate the effects of different factors on crop yields. In the present study, we followed an alternative approach to identify factors that explain field-to-field yield variation, which consisted of farmer survey data, a spatial framework, and multiple statistical procedures. This approach was used to identify management factors with strongest association with on-farm soybean yield variation in the US North Central (NC) region. Field survey data, including yield and management information, were collected over two crop growing seasons (2014 and 2015) from rainfed and irrigated soybean fields (total of 3568 field-year observations). Fields were grouped …

Physio-Chemical And Functional Properties Of Nine Proso Millet Cultivars, Manjot Singh, Akinbode A. Adedeji, Dipak Santra

Biosystems and Agricultural Engineering Faculty Publications

Evaluation of the postharvest properties of nine proso millet cultivars was carried out to determine their physical and engineering properties, which are very useful for designing appropriate systems for process operations such as sorting, drying, heating, cooling, and milling. Nine cultivars of proso millet comprising waxy and non-waxy types, namely Cope, Earlybird, Huntsman, Minco, Plateau, Sunrise, Rise, Dawn, and Panhandle, were obtained from the Panhandle Research and Extension Center, University of Nebraska, Scottsbluff. Results showed significant (p < 0.05) differences in their physical properties, such as sphericity, volume, bulk density, porosity, and angle of repose, which ranged from 0.86 to 0.91, from 3.94 to 5.14 mm³, from 765.49 to 809.67 kg m^-3, from 42.49% to 44.20%, and from 22.98° to 25.74°, respectively. The cultivars were …

Stored Grain Pack Factor Measurements For Soybeans, Grain Sorghum, Oats, Barley, And Wheat, Rumela Bhadra, Mark E. Casada, Aaron P. Turner, Michael D. Montross, Sidney A. Thompson, Samuel G. Mcneill, Ronaldo G. Maghirang, Josephine M. Boac

Biosystems and Agricultural Engineering Faculty Publications

Grain and oilseed crops stored in bins undergo compaction due to overbearing pressure of the grain inside the structure. Thus, volume measurements of grain in bins need to be combined with the amount of packing (usually called pack factor) in addition to the initial density so that the mass in the structure can be calculated. Multiple pack factor prediction methods are in use in the grain industry, but they have only been validated in the literature and compared with field data for corn and hard red winter wheat. Predictions from WPACKING, the program in ASABE Standard EP413.2, and two standard …

Sales And Marketing, Nancye Gannaway

Farm Systems and Economics published reports

Plan, prepare, Prosper - workshop

This document is part of the Plan, Prepare, Prosper program that was developed under the Pilot of Drought Reform Measures ('the pilot'), a joint initiative between the Australian Government and the Western Australian Government. The program aims to support businesses to prepare for drought, climate variability, financial and other challenges.

Today we will be working through your marketing program, and possible strategies for increasing its effectiveness and impact.

We will explore the advantages of target marketing - of focusing your marketing on those customers which best suit your business, and have the greatest potential for …

Air-Propelled Organic Fertilizer Grits Can Be Used To Control Weeds And Provide Nitrogen, Michael Carlson

Electronic Theses and Dissertations

Weeds are one of the biggest challenges for organic growers because of the alternative weed control methods. Air-propelled abrasive grit management has been reported to control weed seedlings in corn and soybeans while maintaining yield. This research examined the weed control, corn and soybean yields, nitrogen mineralization, and nitrogen yield responses from grits. The grits used in this research included: Phytaboost Plant Food 7-1-2 (soybean meal), Sustane 8-2-4 and 4-6-4 (turkey litters), and two non-fertilizer grits: Agra Grit (walnut shells) and corn cob meal. Field studies were conducted from 2015 to 2017 in Aurora, SD, Beresford, SD and Morris, MN. …

Insecticidal Seed And In-Furrow Treatment Recommendations For Soybean And Sunflower, Brady Hauswedell

Electronic Theses and Dissertations

Throughout the 2016 and 2017 growing season, field research experiments were replicated across South Dakota. Many times seed treatments are used prophylactic, which is neither good for the producers or the environment. Producers will be able to reduce production costs, if they only use a seed treatment when necessary. The purpose of the first experiment was to determine the effects of seed treatments in combination with planting date and seeding rate on soybean yield. To determine the effects, two years of field data from four eastern South Dakota locations were compared. Within each year and location we compared two planting …

Influence Of Kernel Shape And Size On The Packing Ratio And Compressibility Of Hard Red Winter Wheat, Marvin C. Petingco, Mark E. Casada, Ronaldo G. Maghirang, Sidney A. Thompson, Samuel G. Mcneill, Michael D. Montross, Aaron P. Turner

Research and Education Center at Princeton Faculty Publications

Grain compaction occurs during bin storage, and its determination is important for the grain mass estimation needed for inventory and auditing. The degree of compaction is dependent on grain type, bin type, moisture content, amount of grain, initial grain bulk density, coefficients of friction, lateral-to-vertical pressure coefficient, and variation in kernel size. Previous studies have correlated several of these parameters, such as bulk density and grain packing, with moisture content. This study investigated the influence of wheat kernel shape and size distribution on packing ratio and compressibility. Two dockage-free hard red winter (HRW) wheat samples, with no shrunken or broken …

Efficacy Of Seed Treatments, Microbial And Biochemical Pesticides For Managing Early Tan Spot And Stripe Rust Diseases Of Wheat, Collins Bugingo

Electronic Theses and Dissertations

Wheat is a major cereal crop in the U.S.A and in the world. However, its production is hampered by a number of factors both biotic and abiotic. Foliar diseases like tan spot caused by Pyrenophora tritici-repentis and stripe rust caused by Puccinia striiformis f. sp. tritici, are economically important diseases causing over 5-55 % yield loss. To assess the efficacy of fungicide seed treatments in the management of early tan spot, two hard red spring wheat cultivars “Select” and “Brick” were treated with seedapplied commercially available combo fungicides metalaxyl + pyraclostrobin + triticonazole and difenoconazole + mefenoxam + sedaxane …

Impacts Of Diverse Crop Rotations And Integrated Crop-Livestock System On Soil Quality In South Dakota, Atilla Polat

Electronic Theses and Dissertations

Crop diversification can be beneficial in improving soil quality parameters. Diverse crop rotations and integrated crop-livestock systems (ICLS), are two examples of crop diversification used in this study to assess soil quality. The objectives of this study were to: (i) assess the impacts of diverse rotations on soil quality parameters, and (ii) assess the impacts of low and high stocking density on soil quality parameters. Both of the studies were conducted separately and are presented as two different chapters. To accomplish objective (i), a long-term experiment was selected which was established near Brookings, South Dakota, USA at USDA-ARS lab in …

Soybean Iron Deficiency Chlorosis: Quantitative Trait Locus Validation And Grain Yield Evaluation, Ahmed Charif

Electronic Theses and Dissertations

Soybean production in most of the Northern Great Plain area has been challenged by iron deficiency chlorosis (IDC), which is a physiological problem with a plant grown in high pH, calcareous soil. Developing IDC-resistant cultivars is the best approach to meet this challenge. Currently, this approach is limited by lack of knowledge about genetic resources and mechanisms for resistance to IDC. The objectives of this research were to validate quantitative trait loci (QTL) associated with IDC and to evaluate the effect of IDC on yield in soybean cultivars. To validate the QTL, a population of 201 recombinant inbred lines, which …

Stability Analysis Of Immunogenic Gliadin Accumulation In Hard Red Spring Wheat (Triticum Aestivum L.), Stacy Lindblom-Dreis

Electronic Theses and Dissertations

Misconceptions regarding plant breeding objectives have led to speculation regarding the increasing prevalence of gluten intolerance, wheat allergy, and celiac disease. It is thought that contemporary wheat cultivars accumulate more immunogenic proteins than older cultivars because of supposed genetic changes effected through plant breeding strategies. This study evaluated the stability of gliadin accumulation in 191 hard red spring wheat cultivars grown in 12 location-years. Two enzyme-linked immunosorbent assays (ELISAs) were developed. A paired t test (N = 34) failed to find a statistically significant difference between the experimental ELISAs and the commercial R5 assay measures of mean gliadin (t = …