Agriculture Commons^™

Investigating Bacterial Community Composition And Antimicrobial Resistance Genes In Beef Cattle, Arena E. See

Department of Animal Science: Dissertations, Theses, and Student Research

While antibiotics have been critical over the last decade for curbing infectious diseases, they have contributed to the rise of antimicrobial resistance (AMR). Infections resulting from antimicrobial-resistant pathogens are correlated with severe morbidity, mortality, and healthcare costs. With the increasing concerns regarding AMR and its emergence, it is paramount to understand not only the effects of antibiotics on microbial community and diversity, but also to develop a novel tool that gives us a better understanding of the spread and functional traits of AMR genes.

To this end, rumen, fecal, and pen surface samples were collected from 72 animals at United …

Discrete Choice Experiments In Agricultural And Food Economics: Two Essays On Information Provision Modalities, Uncertainty Adjustment, And Hypothetical Bias, Monsoïa Arsène Juste Agossadou

Graduate Theses and Dissertations

Stated discrete choice experiments are extensively used in applied economics to study preferences and valuation for new products, as well as costs and benefits of new policies and programs. Moreover, information provision experiments widely use the method to examine information effects on different outcomes. This thesis explores two methodological issues in discrete choice experiments: (i) information provision modalities and (ii) hypothetical bias. The first study examines the effect of information modality by testing the effect of using combined text script and audio clip (treatment) versus only text script (control) to convey information in discrete choice experiments. Specifically, the study elicits …

Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan R. Mcpherson

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

Arbuscular mycorrhizal fungi (AMF) remain a vital obligate symbiont of nearly all plants. It is well established that the symbiosis between AMF and host plant improves plant nutrient acquisition, alleviates abiotic and biotic environmental stressors, defends against plant pathogens, and contributes to overall plant fitness and productivity through modification of the soil habitat. Modifications include increased soil aggregation and stability, carbon sequestration through provision of fungal wall precursors to soil organic matter (SOM) formation, and enhanced nutrient cycling in the mycorrhizosphere. The goal of this dissertation was to assess how AMF respond to nitrogen (N) fertilization regimes in maize cropping …

Causal Forest Approach For Site-Specific Input Management Via On-Farm Precision Experimentation, Shunkei Kakimoto

Department of Agricultural Economics: Dissertations, Theses, and Student Research

Estimating site-specific crop yield response to changes to input (e.g., seed, fertilizer) management is a critical step in making economically optimal site-specific input management recommendations. Past studies have attempted to estimate yield response functions using various Machine Learning (ML) methods, including the Random Forest (RF), Boosted Random Forest (BRF), and Convolutional Neural Network (CNN) methods. This study proposes use of the Causal Forest (CF) model, which is one of the emerging ML methods that comprise “Causal Machine Learning.” Unlike previous yield-prediction-oriented ML methods, CF focuses strictly on estimating heterogeneous treatment effects (changes in yields that result from changes in input …

Analyzing Flexibility As A Risk Management Strategy In Agricultural Systems, Jedidiah Hewlett

Department of Agricultural Economics: Dissertations, Theses, and Student Research

Agricultural businesses deal with uncertainty of all kinds. Uncertainty arising from variability in resources, markets, human factors, and regulatory policy can be sources of significant risks. Acquiring or building flexibility in an operation is one of the ways suggested to manage risk and uncertainty—reducing the impact of negative outcomes and increasing the benefit of positive outcomes. Although flexibility has been repeatedly encouraged for businesses, the definition of flexibility and its value remains ambiguous after more than 80 years of research. Flexibility is often described as a multi-dimensional ability to effectively deal with change in the business operating environment. Flexibility can …

Assessment Of Nitrogen-Based Fertilizer Transport And Microbial Activities In Sandy Soil Profiles In South Texas, Gladys De La Rosa

Theses and Dissertations

Conventional farming is a common practice in Lower Rio Grande Valley (LRGV) and the application of nitrogen fertilizer is essential for plant growth and support. However, managing the rate of nitrogen that is applied can benefit farmers financially and reduce nitrate leaching that can have an adverse effect on the local environment and aquatic systems, e.g., rivers and estuaries. Sandy soils are more vulnerable to water infiltration due to the large proportion of macropores. This study aims to (i) assess how nitrate from a variety of fertilizers (i.e., synthetic and organic) distributes on the top 60 cm layer of a …

The Relationship Between Psychosocial Factors And Food Waste-Related Behaviors Among College Students, Kacy Raquel Wright

Graduate Theses and Dissertations

Food waste is a significant environmental, economic, and social issue, with younger consumers as the most significant contributors. Specific behaviors, like over-purchasing food and misusing date labels, result from a complex interaction between social and psychological factors, which influence food waste among this demographic. The purpose of this study was to identify the psychosocial factors influencing food waste behaviors among college students at the University of Arkansas. Guided by the Theory of Planned Behavior, this study utilized online and face-to-face quantitative surveys, distributed to students enrolled at the University of Arkansas in the spring of 2022. Demographics, attitudes, subjective norms, …

Evaluating Flavor And Aroma Attributes Of Arkansas-Grown Horticultural Crops, Jordan Chenier

Graduate Theses and Dissertations

Arkansas has a climate and geography that allows for the production of unique horticultural crops, including hops (Humulus lupulus L.), blackberries (Rubus subgenus Rubus), and muscadine grapes (Vitis rotundifolia). These crops not only have potential for growers in Arkansas but have unique flavor and aroma attributes that impact marketability. Volatile compounds present in many different agricultural plants are the primary source of biologically-derived aromas and flavors. Therefore, the volatile and other quality attributes of hops, blackberries, and muscadine grapes were evaluated at the University of Arkansas (UA System) Division of Agriculture. The quality, volatile, and sensory attributes of four hops …

Framing The Needs Of School-Based Agricultural Education Teachers To Meet Twenty-First Century Programs Demands, Kayla Marsh

All Theses

Teacher attrition is a historic problem that globally is considered to be an educational crisis. SBAE is not exempt from this crisis with teacher shortages dating back to the passing of the Smith-Hughes Act in 1917. For the past three decades, researchers have studied this phenomenon to better understand the needs of SBAE teachers in order to increase recruitment and retention as well as improve work-life balance.

While several needs are recurring current efforts are not resulting in actionable change for SBAE teachers. To gain perspectives on the problem, qualitative interviews were conducted with SBAE teachers as well as an …

Environmental Weed Risk Assessment Protocol For Growing Non-Indigenous Plants In The Western Australian Rangelands, Geoff A. Moore Mr, Christine Munday Ms, Papori Barua Dr

Bulletins 4000 -

This bulletin is a post-border environmental weed risk assessment (WRA) protocol which is based on the Environmental WRA Protocol developed for the Future Farm Industries Co-operative Research Centre (FFI CRC), but with some changes to reflect the different environment and objectives.

The WRA protocol was developed specifically as a post-border assessment of non-indigenous species that may have agricultural value in the WA rangelands and the risk that they may become environmental weeds. Weeds can occur in many land-use systems including agriculture, horticulture and forestry; however, the focus of this protocol is on the risk that non-indigenous agricultural plants may become …

How The “Blueprint” For Agriculture In Adventist Education Can Be Relevant In The 21st Century, Katherine Koudele

Faculty Publications

No abstract provided.

Potential Psychoactive Effects Of Microalgal Bioactive Compounds For The Case Of Sleep And Mood Regulation: Opportunities And Challenges, Bozena Mccarthy, Graham O’Neill Dr, Nissreen Abu-Ghannam Prof.

Articles

Sleep deficiency is now considered an emerging global epidemic associated with many serious health problems, and a major cause of financial and social burdens. Sleep and mental health are closely connected, further exacerbating the negative impact of sleep deficiency on overall health and well-being. A major drawback of conventional treatments is the wide range of undesirable side-effects typically associated with benzodiazepines and antidepressants, which can be more debilitating than the initial disorder. It is therefore valuable to explore the efficiency of other remedies for complementarity and synergism with existing conventional treatments, leading to possible reduction in undesirable side-effects. This review …

Quantification And Machine Learning Based N2o–N And Co2–C Emissions Predictions From A Decomposing Rye Cover Crop, Deepak R. Joshi, David E. Clay, Sharon A. Clay, Janet Moriles-Miller, Aaron L. M. Daigh, Graig Reicks, Shaina Westhoff

Department of Agronomy and Horticulture: Faculty Publications

Cover crops improve soil health and reduce the risk of soil erosion. However, their impact on the carbon dioxide equivalence (CO_2e) is unknown. Therefore, the objective of this 2-yr study was to quantify the effect of cover crop-induced differences in soil moisture, temperature, organic C, and microorganisms on CO_2e, and to develop machine learning algorithms that predict daily N₂O–N and CO₂–C emissions. The prediction models tested were multiple linear regression, partial least square regression, support vector machine, random forest (RF), and artificial neural network. Models’ performance was accessed using R², …

Limited Effects Of Precipitation Manipulation On Soil Respiration And Inorganic N Concentrations Across Soil Drainage Classes In Northern Minnesota Aspen Forests, Anna B. Stockstad, Robert A. Slesak, Alan J. Toczydlowski, Charles R. Blinn, Randall K. Kolka, Stephen D. Sebestyen

Aspen Bibliography

It is critical to gain insight into the responses of forest soils to the changing climate. We simulated future climate conditions with growing season throughfall reduction (by 50%) and winter snow removal using a paired-plot design across a soil drainage class gradient at three upland, Populus-dominated forests in northern Minnesota, USA. In situ bulk soil respiration and concentrations of extractable soil N were measured during the summers of 2020–2021. Soil respiration and N concentrations were not affected by throughfall reduction and snow removal, which was largely attributed to the limited treatment effects on soil moisture content and soil temperature. …

Registration Of Lcs ‘Valiant’ Hard Red Winter Wheat, P. Stephen Baenziger, S. D. Masterson, J. D. Boehm Jr., Vikas Belamkar, M. D. Barnett, Devin J. Rose, Lan Xu, Stephen N. Wegulo, T. Regassa, Amanda Easterly, Cody F Creech, Dipak K. Santra, G. R. Kruger, G. W. Hergert, R. N. Klein, J. Kolmer, J. Kolmer, M.-S. Chen, Gary L. Hein, R. L. Bowden, M. J. Guttieri, G. Bai, El-Basyoni Salah, J. Poland

Department of Agronomy and Horticulture: Faculty Publications

Historically cultivars developed jointly by the University of Nebraska-Lincoln and USDA-ARS wheat (Triticum aestivum L.) improvement project tend to be late and better adapted to the northern Great Plains. LCS ‘Valiant’ (Reg. no. CV-1196, PI 693223; tested as NE10478-1) was released based on the merits of its earliness, agronomic performance, relevant disease resistances, and end-use quality characteristics and its adaptation to the central Great Plains. As such, the line was licensed to Limagrain Cereal Seeds for their ability to market outside of Nebraska. LCS Valiant hard red winter wheat was released in March 2020 by the developing institutions and …

Who Owns This? Ways That Property Can Be Owned And Transferred In Nebraska, Jessica Groskopf, J. David Aiken

Cornhusker Economics

Discusses ways that property can be owned and transferred in Nebraska in the context of farm management in Nebraska, United States.

Association Analyses Of Host Genetics, Root-Colonizing Microbes, And Plant Phenotypes Under Different Nitrogen Conditions In Maize, Michael A. Meier, Gen Xu, Martha G. Lopez-Guerrero, Guangyong Li, Christine Smith, Brandi Sigmon, Joshua R. Herr, James R. Alfano, Yufeng Ge, James C. Schnable, Jinliang Yang

Department of Agronomy and Horticulture: Faculty Publications

The root-associated microbiome (rhizobiome) affects plant health, stress tolerance, and nutrient use efficiency. However, it remains unclear to what extent the composition of the rhizobiome is governed by intraspecific variation in host plant genetics in the field and the degree to which host plant selection can reshape the composition of the rhizobiome. Here, we quantify the rhizosphere microbial communities associated with a replicated diversity panel of 230 maize (Zea mays L.) genotypes grown in agronomically relevant conditions under high N (+N) and low N (-N) treatments. We analyze the maize rhizobiome in terms of 150 abundant and consistently reproducible …

Missouri Alot - Dc Experience, Amy Bax

Title III Professional Development Reports

I want to thank Lincoln University for sponsoring this trip. I had access to many high-level people in DC that wanted to hear my story of agriculture. These are people that have the power to create legislative practices and policies that are favorable to the agricultural industry. I had the opportunity to advocate for Lincoln and Lincoln University students.

Integration Of Remote Sensing Approaches For In-Season Nitrogen Management, Murilo De Santana Martins

LSU Doctoral Dissertations

Nitrogen (N) management is being conducted at flat rate in Louisiana due to practicality and convenience, but the price of N fertilizer and high breakeven costs are forcing producers to find ways to reduce costs and optimize N application. In this scenario, precision agriculture technologies, specifically the use of optical sensors on board of unmanned aerial systems (UAS) to variable rate N application on farm is showing a promising approach to save inputs and reduce environmental impacts. However, the general goal of this research was to develop and evaluate in-season N management approaches for N recommendation in corn (Zea …

Replacing Fallow With Field Pea In Wheat Production Systems Across Western Nebraska, Samuel T. Koeshall, Amanda Easterly, Rodrigo Werle, Strahinja Stepanovic, Cody F. Creech

Department of Agronomy and Horticulture: Faculty Publications

Integration of field pea (Pisum sativum L.) (FP) into dryland cropping systems has increased due to ecological and economic benefits, paired with a growing market for pea-derived products. Challenges exist in the High Plains that limit the integration of crop rotations to replace fallow periods with FP in wheat (Triticum aestivum L.)- based systems. This experiment compares chemical summer fallow to FP in a fallow– wheat rotation at two locations in western Nebraska. Soil water content, soil fertility, N mineralization, FP yield, and subsequent hard red winter wheat (HWW) yields were recorded. Subsequent HWW yields were not different …