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Synthesis Of Cell Wall Components In Maize Internodes, J H. Cherney, J J. Volenec, G A. Brown

IGC Proceedings (1977-2023)

Cell wall structure affects intake and digestibility of forages by rummants. Before microbial degradation of cell walls can be understood, it will be necessary to have a better understanding of cell wall formation. Internodes of grasses elongate in a_cropetal succession, with two internodes usually elongating s1multaneously. Elongating internodes consist of three regions : 1) a zone of cell division, 2) a zone of cell elongation, and 3) a zone of secondary cell wall deposition. This tissue provides an excellent system for studying cell wall changes in rapidly developing tissues. Our objectives were to : 1) examine changes in cell wall …

Natural And Artificial Drying Effects On Condensed Tannins Of Sericea Lespedeza, T H. University Of Georgia, W R. Windham, J J. Evans, C S. Hoveland

IGC Proceedings (1977-2023)

Sericea lespedeza [Lespedeza cuneata (Dumont-Cours.) G. Don.] is well adapted to acid soils and low fertility but has generally been considered a low-quality forage due to high levels of tannin and indigestible fiber. Tannin levels increase during midsummer (Windham et al. 1988). The most com­monly used assay for tannin in sericea is the vanillin-HCl pro­cedure (Burns, 1963) on oven-dried samples. Oven-drying has been reported to cause increased polymerization or oxidative changes in tannins (Goldstein and Swain, 1963). Fresh-frozen sericea contained higher amounts of extract­able tannin than field-dried forage and fiber digestibility of high-tannin sericea by sheep was much lower …

Quantifying Temperature Effects On Developmental Rate And Plant Quality Of Compact Container-Grown Tomato (Solanum Lycopersicum), Morgan Humphrey

Horticulture Undergraduate Honors Theses

Mean daily temperature effects on plant development rates and quality were evaluated for compact container-grown tomato (Solanum lycopersicum). Compact tomato varieties ‘Siam’ and ‘Red Velvet’ were grown in greenhouses at 18 to 26 °C (Experiment 1) and 20 to 30 °C (Experiment 2) under supplemental high-pressure sodium lighting and 16-hour photoperiod. The number of days to first open flower, first ripe fruit, and from flower to ripe fruit were measured and development rates calculated by taking the reciprocal (e.g. 1/days). Temperature effects were predicted by fitting a linear (for first open flower) and a nonlinear exponential function (for …

Effect Of Soil Amended With Biochar On Growth Dynamics Of Radishes, Colin Brennan, Jake Werner, Ian Townley

CURCI Student Research

How do different percentages (15%, 10%, 5%, 0%) of biochar in soil affect the initial growth rate and final mass of radish plants (Raphanus sativus). We used 15%, 10%, 5% biochar, and using pure soil as our control group. For each soil type, we prepared 12 samples, totaling 48 samples across all conditions. After germination and initial plant growth, the number of leaves and the plant’s height from the top of the plant to the soil (in centimeters) were recorded every school day. The purpose of this study is to better understand if biochar is an effective way to stimulate …

Understanding The Role Of Sabp2-Interacting Proteins Sip432: A Premnaspirodiene Oxygenase Enzyme In Stress Signaling, Cristiana F. Martinez

Undergraduate Honors Theses

This study focuses on the characterization of a SABP2-interacting protein (SIP)-432. SIP432 is a putative premnaspirodiene oxygenase-like P450 enzyme. Premnaspirodiene is a 15-carbon compound that can be converted into antimicrobial compounds by a hydroxylation reaction. The interaction of SIP432 with SABP2, a critical component of salicylic acid-mediated plant immunity, implies a role for SIP432 in plant stress signaling. This study uses the T-DNA knockout mutant of Arabidopsis thaliana SIP432 (homolog of NtSIP432) to help understand its role in abiotic and biotic stress responses. Plants were subjected to abiotic and biotic stress to understand their role in stress response pathways. Gene …

An Australian Chickpea Pan-Genome Provides Insights Intogenome Organization And Offers Opportunities For Enhancing Drought Adaptation For Crop Improvement, Vanika Garg, Rutwik Barmukh, Yan Huang, Annapurna Chitikineni, Kristy Hobson, Bicheng Yang, Yong Jia, Shengnan Bi, Sukhjiwan Kaur, Muhammad Ahsan Asif, Matthew Hayden, Sally Norton, Darshan Sharma, Kadambot H. M. Siddique, Xin Liu, Chengdao Li, Rajeev K. Varshney

Grain and Other Field Crops Research Articles

Summary

Chickpea (Cicer arietinum L.) is an important legume crop that has been subjected to intensive breeding, resulting in limited genetic diversity. Australia is the world’s second largest producer and the leading exporter of chickpea; the genomic architecture of its cultivars remains largely unexplored. This knowledge gap hinders efforts to enhance their genetic potential for production, protection, and stress adaptation. To address this, we generated high-quality genome assemblies and annotations for 15 leading Australian chickpea cultivars using single-tube long-fragment read technology. The pan-genome analysis identified 34 345 gene families, including 13 986 dispensable families enriched for genes associated with key …

A Comparative Analysis Of Small Nuclear Rna Sequences In Spinacia Oleracea, Arabidopsis Thaliana, And Homo Sapiens, Nhi T. Nguyen

2025 Spring Honors Capstone Projects - Archive

In eukaryotes, the structure and function of the Sm core and its associated small nuclear ribonucleoproteins (snRNPs) play a significant role in pre-mRNA splicing. These snRNPs exhibit a high degree of conservation. While plants also utilize alternative splicing, the conservation of plant snRNAs and other non-coding RNA such as snoRNA and scaRNA, which assemble the Sm core, remains largely unexplored. In this study, plant sequences were compared with human sequences using the multiple sequence alignment program Jalview to determine the conservation of snRNPs in other non-coding RNA. Sequences analysis showed that the Sm site in Spinacia oleracea and Arabidopsis thaliana …

Novel Chloroviruses With Unique Glycans On Their Major Capsid Proteins, Cayden J. Homolka

Honors Program: Senior Projects (Public)

Chloroviruses, of the family Phycodnaviridae, are large, dsDNA viruses with a genome of 290 to 410 kb. These virus genomes are so large that they are classified as “giant viruses”. Within this genome, up to 16 tRNAs and 330 to 450 proteins are encoded. Among the massive amounts of genes and proteins are unique carbohydrate synthesis/metabolism genes, which are responsible for the glycosylation of chloroviruses major capsid proteins. In most viruses, these proteins are glycosylated by the host enzymes located in the endoplasmic reticulum. Instead, Chloroviruses encode their own glycosylation machinery; essentially decorating themselves. Furthermore, these chlorovirus glycans are unlike …

A Tale Of Two Asters: Resolving The Plant And Microbial Community Structure Of An Invasive And Native Forb, William Cartelli

Theses, Dissertations and Culminating Projects

Old fields dominated by flowering forbs are frequent targets for ecological restoration, particularly because they are often inhabited by invasive species whose ecological effects remain context dependent and widely debated. While native plants are typically favored in restoration efforts, and invasive species viewed as threats to biodiversity, such classifications may oversimplify ecological function. This study investigates two dominant genera of the Asteraceae family —Centaurea stoebe (L) (non-native) and Solidago spp. (S. rugosa and S. canadensis, both native)—to examine whether biogeographic origin or ecological strategy more strongly influences their impact on above and below ground community structure. Despite their contrasting origins, …

Reevaluating The Role Of Ruppia Maritima: Recruitment Dynamics And Habitat Use By Blue Crabs (Callinectes Sapidus) And Associated Benthic Fauna In A Mid-Atlantic Seagrass Community, Delaney St. Pierre

Theses, Dissertations and Culminating Projects

The value of seagrasses as essential fish habitat is well recognized, but limited data exist on the value of one particular species, Ruppia maritima (widgeon grass), as habitat for fish and invertebrates. During the summer of 2024, I evaluated R. maritima, Zostera marina (eelgrass) and mixed beds to assess their relative value as habitat in Barnegat Bay, New Jersey. Results from throw traps indicated significant monthly differences for pipefish, gobies, blue crabs, grass shrimp, and sand shrimp, driven by active recruitment events. When evaluating habitat type, we found no taxa that were significantly more abundant in Z. marina habitat as …

Nebline, May 2025

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

NEBLINE, May 2025

Tips on Staying Cool During the Heat of a Temper Tantrum

What’s Your BBQ IQ?

May Recipe of the Month — Air Fryer Teriyaki Beef Kabobs

Insect and Disease Control for Organic Vegetable Gardeners

May Garden Guide

Cash Rent Survey

No Matter Where You Live, Submit a Request Before You Dig!

Battling Scales in the Landscape

Three Lancaster County 4-H’ers Modeled Their Sewn Garments at Omaha Fashion Week

Ignite by 4-H 2025 National Conference

May Heart of 4-H Volunteer Award — Dayle Williamson

2024 National Index Study of 4-H Youth

Clover College, June 10–13; Registration Opens in …

Mitigating Nitrogen Losses: The Role Of Enhanced Efficiency Fertilizers In Sustainable Corn Production, Dipesh Giri

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

Nitrogen (N) is essential for crop production, but its inefficient use often leads to environmental losses through nitrate leaching, ammonia volatilization, and nitrous oxide (N₂O) emissions. Enhanced efficiency fertilizers (EEFs), such as nitrification inhibitors (NIs) and urease inhibitors (UIs), have been developed to minimize these losses and improve nitrogen use efficiency (NUE). This research combined a multi-year field experiment and a controlled laboratory study to evaluate how dual-inhibitor fertilizers compare to conventional urea and single-inhibitor formulations in Nebraska cropping systems. The main objective was to understand how nitrogen inhibitors influence N availability, crop performance, and nitrogen losses across different environmental …

Improving Nitrogen Management And Corn Productivity Through Enhanced Efficiency Fertilizer And Cover Crop Integration In Nebraska Cropping Systems, Madhusudhan Adhikari

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

Effective nitrogen (N) management is vital for sustaining corn yield and reducing environmental impacts in Nebraska cropping systems. Three field studies were conducted to evaluate the impact of 1) fertilizer type (anhydrous ammonia [AA] with nitrification inhibitor: enhanced efficiency fertilizer [EEF] or AA without EEF) and N application timing (pre-plant vs. split with side-dress UAN) on in-season soil N availability, crop response, nitrous oxide (N₂O) emissions, residual soil N and N use efficiencies (NUEs); 2) winter cover crop (CC) species and crop rotation variability on CC biomass production, N uptake, soil N dynamics, and cash crop performance in …

Extending Cover Crop Growing Window To Improve The Health Of Environmentally Sensitive Soils, Noshin Ara Tunazzina

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

Sloping and sandy soils are highly susceptible to degradation. The health of these soils could be improved with cover crops (CCs). However, CC effectiveness in improving soil health mainly depends on CC biomass production, which is often low in temperate regions. The question is: how can we increase CC biomass production? Lengthening the CC growing window can be a potential strategy. This study assessed how 1) interseeded and terminated early (2-3 weeks before crop planting) CC, 2) interseeded and terminated late (at crop planting) CC, 3) drilled (after harvest) and terminated early CC, 4) drilled and terminated late CC, and …

Maximizing Crop Production And Profitability Through Double Cropping Corn And Soybean Systems In South Carolina, Bennett Harrelson

All Dissertations

Profitability is critical for farm sustainability, efficiency, and longevity. Over the last decade, corn and soybean commodity prices have fluctuated considerably, and more recently, extreme increases in input prices have narrowed profit margins. Non-traditional cropping systems that can boost profit are becoming of interest to farmers in South Carolina, specifically double cropping soybean behind corn. In this scenario, corn is harvested at high moisture contents and followed by ultra-late planted soybean. However, prior research related to the agronomic production practices of double cropping corn and soybean is minimal. To develop best management practices for growers interested in double cropping corn …

Speed Breeding And Fungal Blight Testing Of The Darling 54 American Chestnut (Castanea Dentata), Virginia G. May

All Theses And Dissertations

The American chestnut (Castanea dentata) was a dominant, foundational forest canopy species in eastern North America until an imported chestnut blight (caused by Cryphonectria parasitica) rendered it functionally extinct across its native range. Biotechnological approaches, like the Darling 54 transgenic line, have potential for future restoration, but need both lab and field evaluations of their breeding and blight tolerance. This thesis adds to the body of knowledge on the Darling 54 American chestnut. This research reports three novel advancements made through indoor breeding and the first systematic field test for blight tolerance of transgenic American chestnuts.

Historically, …

Patterns Of Fire History And Vegetation Changes In The Last 5000 Years: A Paleoecological Study Of Iquitos, Annabel Zwarts

Theses and Dissertations

The vegetation of the Amazonian rainforest is hypothesized to have been shaped by pre-Columbian activities, such as burning and palm management to various extents. Management of palms is hypothesized to have caused some of the most useful species to become hyperdominant in Amazonia. This study investigated the extent to which human activities over the past 5000 years affected palm abundances in mature lowland rainforests near Iquitos, Peru. I used phytoliths and charcoal from soil cores to determine the history of local floras, and modern palm surveys to compare modern phytolith occurrence with modern vegetation. Because pre-Columbian activity clustered along the …

Evaluating Risk And Return Of Corn And Soybean Marketing Strategies Using Monte Carlo Simulation Methods, Johanna Ilves

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

This study evaluates the performance of pre-harvest marketing strategies for corn and soybeans, using Monte Carlo simulation techniques. Given the increasing volatility in commodity prices and the evolving landscape of agricultural markets, producers face growing challenges in developing effective marketing plans that manage risk and enhance profitability. This thesis examines thirteen marketing strategies from 2008 to 2024, including benchmark harvest-only sales and various pre-harvest futures contract approaches. Historical futures price data for December corn and November soybean contracts were used to simulate 1,000 marketing outcomes per strategy per year, capturing a broad range of market conditions. Key performance indicators such …

Landscape Effects On The Beneficial Arthropod Community In Agriculturally Dominated Environments, Hannah E. Stowe

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

Ecosystem services in agriculturally dominated regions rely, at least in part, on arthropods. Environment and biodiversity influence beneficial arthropods in population size, community structure, diversity, and ecosystem service provisioning. Predation is among the most important services provided by arthropods in agroecosystems. Understanding what alters predation and predator activity can support the successful application of biological control and, more broadly, integrated pest management. Land use and edge adjacency, field characteristics, landscape, seasonality, and diel period all alter predatory behavior. Crop fields dominate Nebraska agroecosystems, although interspersed perennial grasslands persist through the Conservation Reserve Program (CRP). Such grasslands supply crucial resources and …

A Case Study On Readiness Of Engineers In Agricultural Technology Start-Ups, Katie Marie Mowat

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

This dissertation explores the perceptions of practicing engineers regarding the skills necessary to be workforce-ready at agricultural technology (ag-tech) start-ups in the Midwestern United States. A qualitative case study methodology is leveraged, combining both interview and job description data. Given their uniqueness, the study divides the ag-tech start-up industry into two subcases: livestock and cropping systems. The Work Readiness Integrated Competence Model (WRICM) is used as the theoretical framework for this study and informs the conceptual framework and analysis processes. The study identified skills that fit into thirteen distinct categories, which are further grouped into four overarching resource groups. Skills …

Gene Editing Approaches To Improving Grain Amino Acid Profiles In Maize And Sorghum, Joseph Preston Hurst

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

Maize grain is deficient in lysine. While the opaque2 mutation increases grain lysine, o2 is a transcription factor that regulates a wide network of genes beyond zeins, which leads to pleiotropic and often negative effects. Additionally, the drastic reduction in 19kDa and 22kDa alpha-zeins causes a floury kernel, unsuitable for agricultural use. Sorghum, closely related to maize, has a similar lack of lysine that can be corrected with prolamin alteration and also subject to the same deleterious kernel texture. CRISPR/cas9 gives researchers the ability to directly target genes of interest. In this research, gene editing was used to specifically target …

Modifying The Comb, Rethinking The Install: Integrated Approaches To Honey Bee Colony Establishment And Winter Survival, Shelby A. Kittle

Department of Entomology: Dissertations, Theses, and Student Research

The European, or Western honey bee (Apis mellifera L.) plays a vital role in global ecosystems and agriculture, providing essential pollination services and producing valuable hive products. However, honey bee colony losses have escalated worldwide, but particularly across the United States due to various stressors, including biotic and abiotic factors, mismanagement, and environmental challenges. This thesis investigates key challenges in honey bee management and explores solutions aimed at improving colony health and productivity.

Chapter 1 provides an overview of the beekeeping industry, detailing its economic importance, services, and products, as well as the many challenges faced by beekeepers. It …

Mechanisms Of Perennial Sorghum Resistance To Sugarcane Aphid Infestation, Esha Kaler

Department of Entomology: Dissertations, Theses, and Student Research

Sorghum, Sorghum bicolor (L.) Moench, the fifth most-grown cereal crop in the world, is a versatile crop, grown across different agro-ecological regions. Sorghum has numerous uses ranging from food and forage purposes to biofuel production. Sugarcane aphid (SCA; Melanaphis sacchari) is a major threat to sorghum production, accounting for 50% to 100% yield loss under heavy infestations. Perennial sorghum can be a sustainable and climate-resilient alternative to the current cereal farming systems. The development of perennial sorghum offers numerous benefits, such as reduced economic inputs, more carbon sequestration, better soil health, and sustainable yields. We employed host plant resistance …

Integrating Genomic And Phenomic Breeding Tools For Wheat Stem Sawfly Resistance In Hard Winter Wheat, Sydney E. Graham

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

The wheat stem sawfly (WSS; Cephus cinctus) is an insect pest that affects wheat (Triticum aestivum) in the Northern Great Plains. This pest causes stem cutting that makes the plants susceptible to lodging and results in up to 30% yield loss. The primary management strategy for producers is utilizing host plant resistance, for which the main trait is stem solidness. This trait increases the pith thickness and provides resistance to the WSS by increasing larval mortality and reducing stem cutting. While stem solidness is largely controlled by a known major gene (SSt1), the phenotypic expression is also …

Biological Reduction Of Perchlorate In Martian Regolith Simulant Using Azospira Oryzae, Brianna Bernhardt

Honors Program: Senior Projects (Public)

Establishing a sustainable human presence on Mars will require in-situ resource utilization (ISRU) to reduce costly and inefficient resupply missions. Despite containing many of the requirements for agriculture, Martian regolith is contaminated with toxic levels of perchlorate (ClO₄^-), threatening human health and agricultural success. Biological remediation using perchlorate-reducing bacteria offers a promising approach to address these challenges. This study investigated the perchlorate-reducing ability of Azospira oryzae, a facultative anaerobe capable of converting ClO₄^- to chloride (Cl^-) through dissimilatory respiration. A. oryzae was cultured in Martian regolith simulant (MGS-1) amended with 0.0%, 0.5%, …

Advancing Mitochondrial Dna Visualization And Dynamics In Plants: Application Of The Mt-Hi-Ness Fluorescent Marker, Madeleine H. Faber

Honors Program: Senior Projects (Public)

Mitochondrial DNA (mtDNA) plays a crucial role in cellular energy production and inheritance, yet its dynamics and exchange remain poorly understood in plant systems due to limitations in visualization techniques. Traditional visualization methods such as exogenous DNA stains and fluorescent protein markers present challenges in specificity and live-cell imaging. To address this challenge, we adapted the MT-HI-NESS fluorescent marker, originally developed for mammalian cells, for use in plant mitochondrial studies. Using Arabidopsis thaliana as a model system, we employed mitochondrial targeting sequences (IVD and AOX) to ensure accurate localization and to confirm mtDNA binding specificity. The validation process included fluorescence-based …

Effects Of Plant Growth-Promoting Microorganisms On Microbial Community Dynamics And Plant Growth Responses Of Aeroponically Cultivated Spinach, Veronica Snow

All NMU Master's Theses

Regional food insecurity caused by the inability to use conventional farming techniques year-round in cold climates increases the need for access to quality, locally sourced, and affordable foods year-round. Shifting from a soil-based system to aeroponics can increase yields, as aeroponic systems are not weather-reliant and can operate year-round. Aeroponics, a subgroup of hydroponics, induces growth by misting nutrient-rich solutions onto the plant roots. These systems use space and water more efficiently and rely less on fertilizers and pesticides but are vulnerable to errors in nutrient application, power loss, and rapid pathogen spread. Adding Vermicompost (VCT) and plant growth-promoting microorganisms …

Assessing Phenotypic Variation Across Generations Of Iberodes Littoralis Under Climate Change, Mariangel M. Fernandez Silva

Electronic Theses, Projects, and Dissertations

The consequences of climate change and anthropogenic activity have decreased wildlife biodiversity. Plants are particularly vulnerable to climate change due to their large biomass on the planet and sessile nature. A particularly useful method for plants to cope with environmental changes is phenotypic plasticity. Adjusting morphological traits through plasticity can help plants cope with environmental changes. Furthermore, plastic responses can be passed down through methods such as changes in DNA sequence or epigenetic modifications.

Our research project focuses on an herb, Iberodes littoralis, a species of concern native to the Siberian Peninsula with approximately thirteen extant populations. The data that …

Characterizing Xylella Fastidiosa Pathogen Dynamics On Diverse Small Fruit Farms, Alexandra Ratay

All Theses

Global agriculture has been threatened for over a century due to the emergence of the plant pathogenic bacteria Xylella fastidiosa (Lysobacterales: Lysobacteraceae) (Xf). Xf comprises five main subspecies and induces severe physiological symptoms in a diverse set of host plant species by limiting xylem function. Xylem-feeding insect vectors can transmit Xf to host plants, spreading disease and reducing fruit yield. Here I studied Xf prevalence on small fruit farms to determine Xf host plant and vector infective status to the Xf subspecies level. I detected Xf in 28 host plants in South Carolina containing either Xf subspecies fastidiosa …

Anaerobic Soil Disinfestation As A Non-Chemical Management Option Against Fungi And Heterotrophic Bacteria In Organic Sweetpotato Production, Meredith Tucker

All Theses

North Carolina is the largest producer of sweetpotatoes in the United States, with South Carolina increasing farming acreage to 2,501 in 2022 compared to 1,300 in 2017. Growers producing conventional and organic sweetpotatoes are equally challenged with managing fungal pathogens due to fungicide resistance or fungicides being unavailable due to environmental regulations, leading many to shift to growing organic crops. Anaerobic soil disinfestation (ASD) is a non-chemical pre-plant management option that uses a carbon amendment, irrigation, and plasticulture to establish an anaerobic environment in soils, killing soil microbes. A greenhouse study was conducted to assess ASD on fungal pathogens and …