Agronomy and Crop Sciences Commons^™

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 …

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 …

Contents, Discovery Editors

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

No abstract provided.

Letter From The Dean, Deacue Fields

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

No abstract provided.

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 19 2018, Several Authors

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

No abstract provided.

New For Discovery: Scholarworks@Uark, Discovery Editors

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

No abstract provided.

Agricultural Information Needs And Food Access In The Stann Creek District Of Belize, Sam E. Harris, Donna L. Graham

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

The purpose of this study was to describe agricultural information sources available to farmers and to describe food access and availability for the people of Dangriga, Stann Creek, Belize. This study used descriptive survey research methods with convenience sampling of the general public (n=22) and of farmers (n = 38) in the summer of 2017. Farmers use a variety of agricultural information sources with the extension service cited most often, followed by friends and fellow farmers. Weather, lack of information, pests, and inadequate access to capital were of primary concern for farmers. Face-to-face meetings were used most often by extension …

Ripeness Attributes Of Arkansas-Grown Peaches And Nectarines At Harvest And During Postharvest Storage, Mary C. Siebenmorgen, Renee T. Threlfall, Margaret Worthington

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

Since peaches and nectarines are a valued fresh-market crop worldwide, evaluating postharvest potential helps determine feasibility for commercial markets. The ripeness attributes of 10 peach and nectarine genotypes were evaluated at harvest (day 0) and after 7 and 14 d storage at 4° C. The fruit was hand harvested at tree ripeness (ripened on the tree) and commercial ripeness (ripened during storage). The attributes of the tree-ripened fruit and commercially-ripened fruit varied at harvest and included chlorophyll (0.04-0.86 abs), peach weight (132-264 g), soluble solids (7.23-12.57%), pH (3.18-4.66), titratable acidity (0.16-1.21%), and flesh firmness (6.92-35.72 N). In general, tree-ripened fruit …

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 = …

Soybean Aphid Biotype 4 Resistance In Soja And Soybean Plant Introductions, Sophia R. Conzemius

Electronic Theses and Dissertations

Soybean aphid, Aphis glycines Matsumura, is a major pest to soybean, Glycine max (L.) Merr. Host plant resistance is a management tactic that uses naturally occurring soybean plant defenses to limit soybean aphid pest damage. Virulent soybean aphid biotypes are able to successfully colonize on certain aphid resistant soybean. Soybean aphid biotype 4 is most virulent, overcoming all commercially available soybean aphid resistant soybeans (Rag1, Rag2, and Rag1+Rag2). Additional sources of resistance to avirulent biotypes have been identified in soja and soybean plant introductions (PIs). This study examined those resistant soja and soybean for resistance to the newly found soybean …

Suppression Of Aflatoxin Production In Aspergillus Species By Selected Peanut (Arachis Hypogaea) Stilbenoids, Victor S. Sobolev, R. S. Arias, Kerestin Goodman, Travis Walk, Valerie Orner, Paola C. Faustinelli, Alicia Massa

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

Aspergillus flavus is a soil fungus that commonly invades peanut seeds and often produces carcinogenic aflatoxins. Under favorable conditions, the fungus-challenged peanut plant produces and accumulates resveratrol and its prenylated derivatives in response to such an invasion. These prenylated stilbenoids are considered peanut antifungal phytoalexins. However, the mechanism of peanut−fungus interaction has not been sufficiently studied. We used pure peanut stilbenoids arachidin-1, arachidin-3, and chiricanine A to study their effects on the viability of and metabolite production by several important toxigenic Aspergillus species. Significant reduction or virtually complete suppression of aflatoxin production was revealed in feeding experiments in A. flavus, …

Application Of Machine Learning Methodologies For Predicting Corn Economic Optimal Nitrogen Rate, Zhisheng Qin, D. Brenton Myers, Curtis J. Ransom, Newell R. Kitchen, Sang-Zi Liang, James J. Camberato, Paul R. Carter, Richard B. Ferguson, Fabian G. Fernandez, David W. Franzen, Carrie A. M. Laboski, Brad D. Malone, Emerson D. Nafziger, John E. Sawyer, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Determination of in-season N requirement for corn (Zea mays L.) is challenging due to interactions of genotype, environment, and management. Machine learning (ML), with its predictive power to tackle complex systems, may solve this barrier in the development of locally based N recommendations. The objective of this study was to explore application of ML methodologies to predict economic optimum nitrogen rate (EONR) for corn using data from 47 experiments across the US Corn Belt. Two features, a water table adjusted available water capacity (AWC_wt) and a ratio of in-season rainfall to AWC_wt (RAWC_wt), were …

Regulation Of Local Auxin Metabolism During Soybean Nodule Development, Suresh Damodaran

Electronic Theses and Dissertations

Legume-rhizobia symbiosis leads to the development of secondary root organs called nodules. Rhizobia bacteria housed inside nodules assimilate atmospheric nitrogen and convert them into plant usable forms thereby reducing the need for fertilizer application in crop legumes like soybean. Nodule development is a coordinated process orchestrated by multiple plant hormones. In soybean, the auxin responsive gene expression was detected in nodule primordia and in the periphery of mature nodules, primarily in nodule vasculature. Auxin hypersensitivity reduces nodule formation in soybean and also polar auxin transport inhibition at the site of nodule development is not crucial for determinate nodule formation. Therefore, …

Quantifying The Short-Term Impacts Of Cover Crops And Grazing On Soil Health Under An Integrated Crop-Livestock System In South Dakota, Vishal Seth

Electronic Theses and Dissertations

Cover crops and grazing under Integrated Crop-Livestock System (ICLS) can impact the rhizosphere nutrient cycling and may have potential to increase the long-term sustainability and economic profitability of agricultural production system. In South Dakota, crop production practices and livestock husbandry are both common which provide the opportunity for ICLS to be successful in this region. However, little is known about the impacts of the cover crops and grazing under ICLS on soil properties in this region. The present study was conducted at South Dakota State University Research Farm (44°20'34.8"N, 96°48'14.8"W), Brookings, SD, to quantify the impacts of cover crops and …

Palmer Amaranth In South Dakota: Growth, Herbicidal Control, And Soybean Yield Loss, Brian Van De Stroet

Electronic Theses and Dissertations

Palmer amaranth is a growing concern in the United States. Previously thought to only be able to occupy the southern United States, this plant can now be found throughout the northern states as well. Infestations of Palmer amaranth can now be found in South Dakota and is raising many concerns. Palmer amaranth is characterized by large growth and can be highly competitive with many important crops. Soybean is an important crop in South Dakota, as well as the rest of the world, and has not escaped the detrimental aspects of an infestation of Palmer amaranth. The objectives of this study …

A Message From The Department Head Of Horticulture And Food Science, Wayne Mackey

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

No abstract provided.

Characterization Of Short-Grain Rice Cultivars Grown In Japan, California And Arkansas, Michiyo Nishiwaki, Eric Lii, Andy Mauromoustakos, Ya-Jane Wang

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

Arkansas and California are the two leading rice-producing states in the U.S. Arkansas predominantly long- and medium-grain rice and California primarily medium- and short-grain rice. Although short-grain rice accounts for less than 2 % of U.S. rice production, the demand for short-grain rice is rising because of increasing popularity of sushi and sake. Because of its premium price and different applications, short-grain rice may open up new opportunities for rice farmers in Arkansas. The objective of this study was to characterize the physical, physicochemical and texture properties of rice cultivars grown in Arkansas versus in Japan and California. Three short-grain …

Plant Community Response To Disturbances In Nebraska Sandhills Upland Prairie, Josiah D. Dallmann

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

Historically, disturbances shaped prairie ecosystems both directly through events like fire and soil moving by animals, as well as indirectly through dynamic rainfall patterns and periodic flux in seed availabilities. We hypothesized that the implementation of several distinct disturbance events in Nebraska Sandhills upland prairie would have measurable effects on plant community composition. We implemented mid-spring fire, soil disturbance in the form of disking, seed addition of native forbs on disked plots, as well as early summer supplemental watering (to mimic minor rainfall events during abnormally dry periods) during 2016 and 2017. Plant community response during the first and second …

Managing Wicked Herbicide-Resistance: Lessons From The Field, Jill Schroeder, Michael Barrett, David R. Shaw, Amy B. Asmus, Harold Coble, David Ervin, Raymond A. Jussaume Jr., Michael D. K. Owen, Ian Burke, Cody F. Creech, A. Stanley Culpepper, William S. Curran, Darrin M. Dodds, Todd A. Gaines, Jeffrey L. Gunsolus, Bradley D. Hanson, Prashant Jha, Annie E. Klodd, Andrew R. Kniss, Ramon G. Leon, Sandra Mcdonald, Don W. Morishita, Brian J. Schutte, Christy L. Sprague, Phillip W. Stahlman, Larry E. Steckel, Mark J. Vangessel

Department of Agronomy and Horticulture: Faculty Publications

Herbicide resistance is ‘wicked’ in nature; therefore, results of the many educational efforts to encourage diversification of weed control practices in the United States have been mixed. It is clear that we do not sufficiently understand the totality of the grassroots obstacles, concerns, challenges, and specific solutions needed for varied crop production systems. Weed management issues and solutions vary with such variables as management styles, regions, cropping systems, and available or affordable technologies. Therefore, to help the weed science community better understand the needs and ideas of those directly dealing with herbicide resistance, seven half-day regional listening sessions were held …

Corn Grain Yield Components And Nutrient Accumulation In Response To Nitrogen, Plant Density And Hybrid, Maria Julia Santoro

Theses and Dissertations--Plant and Soil Sciences

Modern maize hybrids exhibit higher yields, increased biomass production, stress tolerance and greater nitrogen (N) use efficiency. Increased biomass accumulation can influence nutrient uptake and lead to increased nutrient removal. Hybrids were tested at seeding rates (SR) of 74000 (low) and 148000 (supraoptimal) plants ha^-1 and at N rates of 0 (deficient) and 390 (non-limiting) kg N ha^-1. Plants were sampled at V7, V14, R3, R5 and R6 and separated into vegetative and reproductive fractions for determination of dry matter and N accumulation. Grain yield was harvested at R6.

The high SR and high N treatment combination …

Measured Soil Hydraulic Properties As Rzwqm2 Input To Simulate Soil Water Dynamics And Crop Evapotranspiration, Saadi Sattar Shahadha

Theses and Dissertations--Plant and Soil Sciences

Agricultural system models integrate many different processes that cannot all be measured in field experiments and help quantify soil water dynamics, crop evapotranspiration, and crop growth with high temporal resolution. Understanding soil water dynamics and crop evapotranspiration is essential to improve agricultural management of field crops. For example, the interaction between nitrogen application rate and water dynamics is not sufficiently understood. In most cases, model simulations deviate from field measurements, especially when model input parameters are indirectly and unspecifically derived. The extent to which measured soil hydraulic property inputs decrease the discrepancy between measured and simulated soil water status is …