Agronomy and Crop Sciences Commons^™

Featured Faculty Mentor/Student Team, Kelly Loftin, Eva Berryhill

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

No abstract provided.

Instructions For Authors, Discovery Editors

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

No abstract provided.

Quantifying Landscape Variability Of Dynamic Soil Properties In The James River Valley, Eastern South Dakota, Sage Reuter-Schmitt

Electronic Theses and Dissertations

Dynamic soil properties (DSP) are a great tool for monitoring land-use change, and they are frequently used as soil health metrics. The NRCS and other soil researchers often use repeating, single-point or nested-point DSP studies to monitor and better understand the effects of land management decisions. While these studies capture the temporal variability of DSPs, they overlook the field-scale spatial variability of DSPs. Soil organic carbon (SOC) provides critical services to the ecosystem and other environments. These traits, as well as its susceptibility to management decisions, make SOC an important soil health indicator and DSP. Measuring SOC is often time …

Isolation And Characterization Of Rhizobia Bacteria From Midwest Soils, Jr Loya

Electronic Theses and Dissertations

Symbiotic bacteria, known as rhizobia, can colonize the roots of legume plants and then convert atmospheric nitrogen into a usable form by the host through the process called biological nitrogen fixation (BNF). Many of these bacteria produce other plant-growth-promoting benefits, such as nutrient acquisition, phytohormone production, and the modification of plant stress responses. Agricultural inoculants made from these bacteria have helped reduce the need for man-made nitrogenous fertilizers, known causes of pollution and eutrophication. There are additional benefits in developing bacteria inoculants local to regional soils. The ability to survive and compete in Midwest soil and climates present an opportunity …

Introduction To Hydroponics- 2025-2026 Workshop Handbook, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Hydroponically grown plants grow faster than traditional production systems, with greater productivity, greater palatability, and having optimal visual character. Three principal components of a system include the plant support platform, a nutrient solution reservoir, and an interface for the root-solution. This publication provides in-depth explanation to system design, evaluation of water quality, nutrient formulation, and prototype systems that can be easily constructed for those wanting to explore hydroponics, such as educators, organizational leaders, or home enthusiasts.

An Economic And Production Analysis Of Seaweed Farms In California And The Pacific Northwest, Brian Donovan

Cal Poly Humboldt theses and projects

Since the early 2010s, the seaweed aquaculture industry has steadily expanded in the United States, with states like Alaska, Maine, Hawaii, and Connecticut leading the way in the development of this emerging sector. However, information gaps remain concerning certain aspects of the domestic seaweed aquaculture industry. The purpose of this study was to examine the status of the seaweed aquaculture industry along the West Coast of the United States; specifically in the states of California, Oregon, and Washington. Seaweed farmers in these states were invited to voluntarily complete surveys asking important production, economic, and commercial questions regarding their operations. Data …

Microbial And Plant Biodiversity In Appalachian Agroecosystems And Their Implications For Soil Health, Kinsey Reed Close

Graduate Theses, Dissertations, and Problem Reports (ETD)

The sustainability of agricultural landscapes depends on understanding the complex interactions between plants, soil, and microbes. In Appalachia, a region shaped by complex terrain and long histories of human and ecological interaction, small family farms produce hay, livestock, and row crops. These agroecosystems, though often treated as “artificial” by many ecologists, have the potential to support both food production and biodiversity conservation if managed with an understanding of ecological complexity. This dissertation examines how plant and microbial diversity interact with soil and management to influence nutrient cycling, soil health, and long-term resilience in Appalachian agricultural systems. A literature review revealed …

Effects Of Round-Up On The Environment, Sandra J. Marcu

Journal of Earth and Life Science

Many people around the world have used and still currently use Roundup but are unaware of the effects it has on the environment. Roundup is a spray on application weedkiller that is widely used around the world today both residentially and commercially. It enables its user to grow a garden or a field of crops with a no-tilling approach to eliminate weeds. It is a well-known and popular choice for killing weeds that has been around since the mid 1970’s (Oca, 2017). John Franz, a Monsanto scientist discovered that glyphosate (main ingredient in Roundup) was an herbicide or weedkiller, and …

Physiological And Genetic Studies Of Hydrotropism In The Maize Primary Root, Muyu Gu

Electronic Theses and Dissertations

No abstract provided.

Epidemiological And Diagnostic Approaches For Soybean Cyst Nematode In South Dakota, Nabina Karki

Electronic Theses and Dissertations

Soybean cyst nematode (SCN), Heterodera glycines (HG) Ichinohe, is an endoparasitic nematode and one of the major yield-limiting pathogens of soybean (Glycine max L.) in the United States. Soybean cyst nematode alone accounts for more than $1.5 billion economic loss annually in North America. First reported in the U.S.A. in 1954 in New Hanover County, North Carolina and later in 1995 in Union County, South Dakota. Prior to this study, SCN has spread in 34 counties in the state. As a soil pathogen, which can adapt to most soil conditions under soybean production and beside soybean, it is hosted on …

Cover Cropping Strategies For Improving Weed Suppression, Yashar Askarzadeh

Electronic Theses and Dissertations

Cover crops (CCs) play an essential role in sustainable agriculture by providing multiple ecosystem services. However, adoption remains low due to concerns about economic returns, management complexity, and potential yield reductions in cash crops. Applying CCs uniformly across fields without accounting for spatial variability can result in inconsistent outcomes. A precision cover cropping system (PCCS), which incorporates site-specific management zones (MZs), offers a more targeted approach to improving performance while minimizing costs and uncertainties. This study explores the interaction between CCs and field variability through complementary field and greenhouse experiments. The field experiment demonstrates that field heterogeneity significantly influences CC …

Geometric Modeling, Reconstruction And Evaluation Of Maize Leaf Morphology In 3d, Zhaocheng Xiang

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Maize is a vital crop for global food security, yet quantitative characterization of its three-dimensional (3D) morphology remains a major challenge due to the geometric complexity of curved leaf structures and occlusions during data collection. This work presents an integrated framework for the digital reconstruction, parametric modeling, and functional analysis of maize leaf morphology and canopy architecture, advancing the precision and interpretability of phenotyping and modeling in smart agriculture.

First, we propose a descriptive and parametric model that represents maize leaves through three fundamental components: midrib, cross-section, and blade contour. Each is described by geometric curves and controlled by biologically …

Leaf-Based Varietal Categorization Of Sweetpotato (Ipomoea Batatas L. Lam.), A Potentially Healthful Vegetable, Using Image Processing And K-Means Clustering, Shahidul Islam, Md Towfiqur Rahman, Md Hamidul Rahman, Abdul Momin

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Sweetpotato (Ipomoea batatas Lam) leaves contain higher concentrations of phenolic compounds, flavonoids, and carotenoids that are remarkable in health promotion. However, the nutrient content in sweetpotato leaves varies from variety to variety, and leaf shape and color are the key identifying factors for the varietal classification of sweetpotatoes. So, detecting sweetpotato leaves is essential for the in-situ identification of sweetpotato varieties and for developing intelligent agricultural systems. This study aimed to create a leaf-shape-based varietal classification technique for sweetpotato using image processing techniques coupled with a K-means clustering algorithm. 38 leaf images (RGB) of two sweetpotato cultivars were collected …

Management Adaptations To Sustainably Increase Soybean Yield And Water Productivity Through Field Studies And Crop Modeling, Mounica Talasila

Theses and Dissertations--Plant and Soil Sciences

Soybean (Glycine max [L.] Merr.), a major crop in the upper U.S. Mid-South, is predominantly cultivated under rainfed conditions, where variable precipitation frequently induces water stress and limits yield potential. Consequently, irrigation adoption has been increasing across this region. Determining the optimal cultivar maturity group (MG) and planting date (PD) for both rainfed and irrigated systems is essential for maximizing yield and improving water use metrics. Evaluating crop water use efficiency (WUE; yield per unit of seasonal evapotranspiration) and total water productivity (WP; yield per unit of total water input from precipitation and irrigation) is critical to developing such …

Factors Impacting Germination, Emergence, And Establishment Of Direct Seeded And Transplanted Hemp (Cannabis Sativa L.), Paul Cockson Dr.

Theses and Dissertations--Plant and Soil Sciences

Industrial hemp (IH) establishment has many challenges including: poor emergence, low stand establishment, and variable plant development in direct seeded hemp. In floral hemp production, quality transplant production is a challenge with seedlings often becoming root bound and etiolated. In both direct seeded and transplant hemp, the relationship between root vigor and vegetative growth has not been studied and may prove insightful for managing emergence and establishment challenges. The goals of this study were three-fold: 1) to measure and describe root system architecture (RSA) and root phenotypes observed in selected IH cultivars especially in regard to identifying agronomically important RSA …

Evaluation Of Poaceae Species And Suppression Application Methods For Perennial Groundcover In Corn, Hallie A. Sandeen

Theses and Dissertations--Plant and Soil Sciences

Intensive grain production aims to provide food security but has depleted once-perennialized land. Perennial groundcover (PGC) offers ecosystem services to intensive annual corn (Zea mays L.) production. In past research conducted in the U.S. Midwest, Kentucky bluegrass (Poa pratensis L.) has been the standard PGC species. However, it is slow growing and difficult to suppress. To characterize the PGC system in the midsouth, two separate field trials in Lexington, Kentucky, were conducted to (i) compare the first-year establishment of alternative cool-season species to Kentucky bluegrass, with and without a spring-applied broadleaf herbicide, and their impact on corn grain …

Greenhouse Management For The Smaller Structure--Educational And Hobby, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Greenhouses used for teaching or by hobbyist are smaller than those used for commercial production or found in the retail environment. Structural materials, covering, mechanical equipment, and control systems often are packaged as a kit made available through greenhouse suppliers. Supplier construction services may not be available, in which buyers must use local contractors to complete the installation. Greenhouses are unique structures that differ greatly from sheds or other outbuildings. They have coverings that allow maximum light transmittance, protected from UV degradation, and can handle wide inside to outside temperature extremes. This extension circular provides valuable information on the character, …

Addressing Food Security In Cameroon, Stacy A. Adams, Ruth Abunaw Besong

Department of Agronomy and Horticulture: Faculty Publications

Cameroon Africa has experience a period of nearly a decade of unrest as militants fight for independence for two Anglophone regions within a predominantly Francophone country. The English-speaking minority have felt aggrieved for continued erosion of rights by the central government. Protests have rapidly spread since 2016, causing closure of schools, businesses, and medical facilities. People have lost homes and been displaced, negatively affecting food production and crop availability. The United States Department of State leads an effort of diplomacy beyond emergency food relief through the Mandela Washington Fellowship that connects American professionals to innovative and impactful young African leaders. …

Terrarium- An Ecosystem In A Jar, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

STEM education is supported through hand's-on activities in the classroom. Content understanding and reaffirmation of knowledge is supported through this informative STEM-Quick card that teachers or extension educators can distribute to participants for reference. Terrariums provide an example of a closed ecosystem where water and carbon cycling is demonstrated and plant growth can be observed. This card presents the steps to building and caring for an easy to create terrarium.

Advancing Root Trait Measurements For A Deeper Understanding Of Soil Biogeochemistry, Brian Rinehart

Theses and Dissertations--Plant and Soil Sciences

Climate change is disrupting (agro)ecosystems, with the potential for significant losses in crop productivity and ecosystem resilience due to changes in water and biogeochemical cycling. These disruptions can also release more carbon dioxide into the atmosphere through the degradation of soil organic matter. Plant roots have emerged as a potential tool for mitigating these effects, given their roles in plant function and in driving soil biogeochemistry. While this interest is growing, our ability to implement root trait selection is limited due to constraints on characterizing roots and limited clarity on the effects of traits on plant and ecosystem function. My …

Scalable Machine Learning Framework For Adaptive Irrigation Management Of Maize And Soybean In The U.S. Midwest, Precious N. Amori, Derek M. Heeren, Yeyin Shi, Eric Wilkening, Ivo Z. Goncalves, Guillermo R. Balboa, Daran R. Rudnick, Abia Katimbo, Randall S. Ritzema

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Conventional soil water balance (SWB) irrigation scheduling tools, such as FAO-56-based Spreadsheets and the Spatial Evapotranspiration Modeling Interface (SETMI), rely heavily on manual inputs and periodic field measurements, leading to delayed recommendations and missed opportunities to prevent crop stress. More critically, these tools lack the computational scalability and adaptability to leverage the high-frequency, high-volume datasets now available through modern sensing technologies. As precision irrigation increasingly depends on integrating spatially and temporally nuanced field information, there is a pressing need for decision-support systems that can process Big Data efficiently and respond in real-time. To overcome these limitations, we developed and validated …

Longitudinal And Ensemble Modeling Of Beef Cattle Feed And Water Intakes, Nathan El Blake

Graduate Theses, Dissertations, and Problem Reports (ETD)

Beef cattle production remains a cornerstone of global food systems, providing highly bioavailable protein and essential micronutrients that are difficult to secure from plant-based foods alone. Yet this production is also resource-intensive, requiring substantial land, feed, and water inputs while contributing significantly to greenhouse gas emissions. Efficiency of dry matter intake (DMI) and water intake (WI) is central to both productivity and sustainability, but accurate measurement of these traits—particularly in grazing systems—remains a major limitation. National WI standards continue to rely on pen-level data collected in the 1950s, while most existing DMI prediction equations perform poorly when applied beyond the …

An Apple A Day: Have The Growing Conditions Of Apples In Maine Changed Over The Past 20 Years, Anooshka Sethi

Honors Theses

Climate change is increasingly affecting the growing conditions that farmers face. This study focused on if and how the growing conditions of apples have changed over the past two decades. Apples are an economically, socially, and culturally important crop to Maine's agriculture landscape. By production acreage, Maine is the second largest state in New England, with 2700 acres of land used to grow apples (USDA NASS CoA, 2022). A unique characteristic of agricultural production in Maine is that most farms are small-scale, run by families or small groups, making adverse changes to the growing conditions of a major crop in …

Evaluating The Adaptation Of Taro (Colocasia Esculenta) To West Virginia Climatic Conditions, Kayode Joseph Ajayi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Climate change impacts agriculture and food security across the globe, therefore higher temperatures could increase in the length of the growing period and new crops would take advantages of. Research was conducted in Morgantown, WV in 2022 and 2023 to understand the growth pattern of Taro in West Virginia, and to analyzing the chemical composition of the Taro plant. The experiment was a completely randomized design in direct planting-low tunnel technology (2 replications, and 10- plants/plot), and two fertilization treatments (fertilized and non-fertilized). Spacing was 1 m within and between rows. Data were subjected to ANOVA using SAS. Dependent variables …

Improving Reduced Tillage Vegetable Systems For The Northern Great Plains: How Does Early Season Soil Tarping (Solarization And Occultation) Reduce Weeds, Affect Soil Health, And Protect Yield?, Hannah Voye

Electronic Theses and Dissertations

Soil tarping (solarization and occultation) is a no-till weed management practice gaining popularity in the United States for small scale vegetable growers. While many studies have been conducted using variations of this tool in the Northeast United States, minimal research has been done in the windier, sunnier, Midwest climate. Our research explored the effectiveness of early spring solarization and occultation to manage weeds and produce viable onion yield in Eastern South Dakota. Occultation tarps placed in early spring included double sided black and white silage tarps with tarps placed black side up or white side up, each placed 6-, 4-, …

Remote Sensing - Based Mapping And Analysis Of Winter Cover Crop Adoption For Sustainable Agriculture, Minnehaha County, Belinda Buechler

Electronic Theses and Dissertations

Winter cover crops planted by farmers such as cereal rye, crimson clover, radishes, hairy vetch, and winter wheat are used to conserve and protect the soil during winter. These crops offer numerous benefits such as improving soil health, reducing erosion, fixing nitrogen, increasing carbon sequestration, and weed suppression. Over time, winter cover cropping has been recognized as a sustainable agricultural practice and has gained attention from Federal and State conservation programs, farmers, and non-governmental organizations. Due to their vital benefits, agencies such as the United States Department of Agriculture (USDA), Natural Resources Conversation Services (NRCS) have partnered with cost-share programs …

Foliar Corn Diseases In South Dakota: Visual Disease Surveys And The Genetic Studies Of Tar Spot And Bacterial Leaf Streak, Ciera Kotaska

Electronic Theses and Dissertations

Corn (Zea mays L.) is one of the most important crops in South Dakota and the United States. Each year, a variety of diseases impact the production of corn in South Dakota, though very little documentation about these diseases exists in the state. This survey documents the foliar diseases of corn and the distribution of each to create a baseline of knowledge. An additional genetic study was conducted to determine the organisms associated with tar spot of corn and bacterial leaf streak (BLS), two emerging diseases in South Dakota. A variety of studies have been conducted on tar spot, caused …

Evaluation Of Strip-Tillage And Banded Phosphorus And Potassium Fertilizer For Corn Production In Eastern South Dakota, Charles N. Tesch

Electronic Theses and Dissertations

In South Dakota, the adoption of no-till and other conservation tillage practices has grown in recent years. However, conventional tillage is still a common practice in the eastern third of the state, negatively affecting soil health and the environment. Strip-tillage has gained interest in this region as a way to transition to conservation tillage while retaining some benefits of conventional tillage. Strip-tillage also provides the ability to subsurface band nutrients, particularly phosphorus (P) and potassium (K) fertilizers within the tillage strip, potentially improving nutrient accessibility and recovery while reducing environmental risks. This study aimed to investigate (i) the effects of …

Quantification Of Auxin-Cytokinin Response During Lateral Root And Nodule Development In Medicago, Aniket Singh

Electronic Theses and Dissertations

Lateral roots (LRs) and nodules are post-embryonic root organs in legumes formed through the activity of de novo meristem. LRs, which are present in all vascular plants, are developed primarily via intrinsic developmental cues, whereas root nodules, found only in a small group of plants known as legumes, are formed in response to legume–rhizobium symbiosis. LRs arise from the pericycle layer of the root, whereas nodule initiation can begin either in the pericycle (indeterminate nodules with persistent meristem, as in Medicago) or in the cortex (determinate nodules with transient meristem, as in soybean), pointing toward a conserved developmental origin, especially …

Fungal Biotransformation Of Thin Stillage And Soybean Hulls And Bacterial Production Of Lysine In Ethanol Industry Co-Products, Bhawana Khadka

Electronic Theses and Dissertations

Thin stillage (TS) and whole stillage (WS) are major by-products of the corn ethanol industry. These by-products are generated in large quantities and contain nutrients that remain after yeast fermentation. Current industrial utilization of these by-products involves a series of downstream processing steps such as centrifugation and evaporation, which are energy-intensive and often result in nutrient losses. Traditionally, these by-products are dried to produce distillers dried grains with solubles. In this study, microbial fermentation was investigated as an alternative bioprocessing tool to expand the utilization of these by-products. The first objective was to explore the upcycling of TS, both alone …