Digital Commons Network^™

Adopting New Technologies For Grazing Lands: The Role Of Decision Systems, John A. Ludwig, Steve Marsden

IGC Proceedings (1977-2023)

The management of Australia's arid and semi-arid grazing lands involves the consideration of many complex and interconnected issues related to both ecological and economic factors. Climates are highly variable across these lands and markets fluctuate widely; decision making is . difficult at the best of times, As new grazing and land management technologies become available through research organisations, such as CSIRO, the adoption of these technologies is a prime concern, Traditionally, State extension services provide this information to grazing land managers, which has proven effeclive for transferring information about current short-term problems (e,g,, locust plagues) and easy to apply products …

Applying "Farmer-First Research" In New Zealand, A F. Mcrae, F M. Anderson, R Brazendale

IGC Proceedings (1977-2023)

The disciplinary orientation and other characteristics of traditional agricultural research may result in farmers' research needs not being central to the research proces·s. A Farmer-First Research programme (FFR) has been initiated to complement the traditional research approach. This programme involves collaboration with hill country sheep and beef farmers chosen at random from across the fuff range of farmer circumstances. It sets out to diagnose and describe where scope· exists to Improve farmers' circumstances, and lo design and test relevant innovations on-farm. In addition to seeking to improve research output for far1ners, the· programme has the objective of evaluating the Farmer-First …

Technology Transfer Strategies For Products Of Environmental Research And Development Projects, N D. Macleod, J A. Taylor, P.G H. Van Beek, P N. Vance

IGC Proceedings (1977-2023)

Potentially high net benefits from Research and Development on sustainable grazing systems will not be captured unless the outcomes are adopted. Adoption is a complex process, often requiring integration with other technologies, and specialised extension packages. Technology transfer strategies based on experiences with relatively simple innovations are unsuited to more complex environmental innovations, A 6-stage interactive process involving researchers, extension specialists and potential end-users is suggested.

Development Of Environmental And Agricultural Professionalism, Robert F. Barnes, Thomas J. Hall

IGC Proceedings (1977-2023)

The American Society of Agronomy {ASA) is' co-ordinating the development of a \ioluritary certification programme for the men and women who··make nutrient management strategies for farmers .• This paper examines the need, "history and obstacles in developing a crop advisor certification programme. Past arid proposed state and national legislative initiatives have indicated to some industry leaders that certification programmes' will be needed ·to operate in the coming regulat6ry environment. Other members· of industry· feel chat voluntary certification will bring on mandated programmes, The' differences in outlook, the diversity of the audience and the academic orientation of ASA ·have all created …

Grazier's Pattern Of Understanding Vegetation In The Semi-Arid Rangelands Of New South Wales, S.M M. Kersten, R L. Ison

IGC Proceedings (1977-2023)

A matrix ranking (MR) technique was used by graziers in western New South Wales to rank rangeland plants according to preference. Graziers preferred a variety of plant species in their paddocks: "bushes" and "50f1 feed", perennials and annuals, winter-and summer­growing plants, on both stock-based and non-stock-based criteria, The criteria for evaluation were rarely independent of each other nor of different soil types on the grai:ier's property. Drought resistance was perceived as one of the more important criteria, followed by stock-based criteria such as "nutritious", "palatable" or "quick fattening" stock feed. The utility of MR for allowing graziers' knowledge to be …

Composition Of The Fractions Of Dry, Mature Subterranean Clover Digested In Vivo And In Vitro, L Klein, S K. Baker

IGC Proceedings (1977-2023)

A modified pepsin-cellulase procedure was used to improve the prediction of in vivo digestibility of dry, mature subterranean clovers (Trifolium subterraneum). Feed, faeces, and the residues from this /11 vitro procedure and the i11 vitro procedure of Tilley & Terry were analysed for protein, ash and fibre fractions lo determine the composition of the cell-wall functions that were digested. The extent of digestion of the cell-wall fractions differed between the two in vitro procedures, but the cell-wall fraction that was digested contained similar proportions of cellulose, hemicellulose, protein and lignin. The cellulose and protein contents of the cell-wall digested …

Effect Of Plant Leaf Age On The Production Of Tannins, Phenols, Proanthocyanidins And Flavanols In Eulalia Villosa, M M. Wolfson, E W. Du Toit, P Chesselet

IGC Proceedings (1977-2023)

Histochemical and biochemical analyses have confirmed the presence of condensed tannins in a number of southern African tropical grasses. The ability to precipitate proteins, total phenols, condensed tannin and proanthocyanidin levels were significantly higher in mature leaves of Eulalia villosa than in young leaves. The ratio of condensed tannin to Jlavan 3,4-diols indicated that the young leaf material contained more monomeric unpolymerised flavan 3,4-diol units than mature leaves. The trend is repeated in the ratio 'of proanthocyanidin to flavan-4-ols, These low molecular weight proanthocyanidin precursors probably do not have the ability to precipitate proteins, The histochemical tests can be used …

Effect Of Inoculants And Absorbents Incorporated In Grass Silage On Silage Quality, Effluent Production And Animal Performance, Raymond Jones

IGC Proceedings (1977-2023)

Unwilled ryegrass crops (151 kg DM) were enslled in 70-t bunker silos. Crop analysis (g/kg/DM) was water-soluble carbohydrates 153, nitrogen 24.1 and predicted digestibility (DOMD) 0.67. Molassed sugar beet feed pellets were incorporated at a rate of 25 kg/t in the harvested crop with or without inoculant treatment ("Live Systems", MMB, UK), and compared with a control silage with no additive. Absorbent addition with or without inoculant significantly reduced silage pH and ammonia-N compared with the control. Inoculant treatment further increased lactic acid content. Silage effluent production was reduced by up to 33% by absorbent inclusion with effluent DM losses …

Near-Infrared Spectroscopy Analysis Of The Nutrient Content Of Dairy Pastures, R C. Kellaway, C Stimson, R J. Tassell

IGC Proceedings (1977-2023)

Pasture samples from temperate and tropical species were collected before and after grazing, at regular intervals, on 3 dairy farms in New South Wales over a period of 3 years. All samples (n=693) were analysed on a near-infrared (NIR) spectrophotometer with a scanning monochromator. Subsets of samples selected for calibration and validation, were analysed by wet chemistry methods for estimated metabolisable energy (MID), crude protein (CP), organic matter (OM), acid-detergent fibre (ADF), Ca, P, Mg, K, Na, S, Cu, Mn and Zn. These data were used lo develop NIR equations using partial least squares analyses. Standard errors of laboratory analysis …

Influence Of Oxygen Leakage Through Stretch Film On Quality Of Round Bale Silage, P Lingvall, C M. Pettersson, P Wilhelmsson

IGC Proceedings (1977-2023)

The ensiling-process is based on anaerobic conditions. Therefore, it is important to get "air tight" parcels covering big-bale silage. Wrapping round bales wilh stretch film has improved silage quality, and reduced diy matter (OM) and energy losses. In this experiment we studied the influence of stretch film quality, film thickness, .storage temperature and storage place on fermentation, microbial growth/ and DM losses. Additionally, oxygen permeability of stretch film wrapped in 4 or 6 layers around artificial bales (metal) and DM losses was tested In a model. High storage temperature, low total film thickness and high film permeability to oxygen increased …

Proceedings Of The 2024 Berry Summer Thesis Institute, University Of Dayton. University Honors Program, Magdelyn Stewart, Noah Clemens, Sarah Theewis, Henry Salisbury, Kevin Johnston, Adin Stoller, Meggie Bailey, Erin T. Flaherty, Adelyn Hughes, Marc Nya

Proceedings of the Berry Summer Thesis Institute (2013-Present)

Thanks to a gift from the Berry Family Foundation and the Berry family, the University Honors Program launched the Berry Summer Thesis Institute in 2012. The institute introduces students in the University Honors Program to intensive research, scholarship opportunities and professional development. Each student pursues a 12-week summer thesis research project under the guidance of a UD faculty mentor. This contains the product of the students' research.

Contents:

Testing the Influence of Lithology and Ice Sheet Dynamics on Waterfall Formation in Hocking Hills State Park // Magdelyn Stewart

Step-Rate Manipulation for Improved Performance: A Review// Noah Clemens

Alfred Rosenberg: An …

Diseases Of Cannabis Sativa And The Epidemiology And Molecular Diversity Of Neofusicoccum Parvum, Hannah V. Zima

Graduate Theses and Dissertations

Cannabis sativa has been an underutilized agricultural resource in the United States, largely due to federal regulations distinguishing marijuana from hemp. In 2018, Congress passed a Farm Bill, which defined hemp as C. sativa containing a tetrahydrocannabinol (THC) level of no more than 0.3%. As a result, commercial hemp production began in most states in 2019, including Arkansas, and was accompanied by numerous challenges like diseases and pests. The research on the epidemiology of diseases affecting C. sativa is limited, and understanding the pathogens is in its early stages in the U.S. For this study, an initial disease survey was …

Detection Of Fungicide Resistance In Population Of Corynespora Cassiicola From Arkansas Soybean And Cotton Fields, Rafael Zaia

Graduate Theses and Dissertations

Target spot, caused by the fungus Corynespora cassiicola, has reemerged since 2016 as an economically important disease on soybean and cotton across the Southern U.S. The quinone outside inhibitors (QoI) and succinate dehydrogenase inhibitors (SDHI) are important fungicide classes used to control foliar diseases in soybean and cotton. The efficacy of these products is rapidly decreasing, impacting control, and causing significant yield losses. The overall objective of this study was to determine the risks associated with chemical control by screening fungicide sensitivity, evaluating target site alterations, and analysis of disease control efficacy and yield response of fungicides for soybean in …

Fungal Pathogen Control And Microbial Ecology: Insights From Soybean Seed Production, Samantha Rigo Segalin

Graduate Theses and Dissertations

This study evaluated the effects of planting date (PD), seed vigor, and chemical seed treatments on the plant stand and yield of two soybean cultivars with different maturity groups (MGs) across four locations in Arkansas from 2018 to 2021. Early planting in early May (early PD) led to higher plant stands and yields compared to late planting in early June (late PD). The interaction between planting date and cultivar was significant, with both cultivars showing higher plant stands on early planting dates. Seed vigor and seed treatment also significantly impacted plant populations; high-vigor seeds planted early resulted in better stands …

Developing A Controlled Traffic (Tramline) Farming System, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Controlled traffic farming (CTF) is a farming system built on permanent wheel tracks where the crop zone and traffic lanes are permanently separated. It can improve profitability and sustainability.

Implements for seeding, spraying, spreading and harvesting have a particular span, or multiple of it, and all wheel tracks are confined to specific traffic lanes.

CTF increases profit by more yield, better grain quality, improved operation timeliness, and reduced costs. The environment can improve, with less nutrient leaching, less water erosion, better water infiltration, and less greenhouse gas emission. Implementation needs a clear, long-term plan, and prioritisation of soil health.

Another …

Assessing Soil Properties & Suitability For Optimized Irrigation Development In Sudan, Northern Africa, Suhib O. Hamid

Department of Agricultural and Biological Systems Engineering: Masters Project Reports

In Chapter 1, soil properties essential for efficient irrigation are thoroughly assessed. Factors such as soil texture, infiltration rates, and nutrient content are analyzed to provide insights into the selection of modern irrigation systems. Utilizing data collected from 3,192 locations through GPS and laboratory analyses, alongside sophisticated ranking systems, the research determines the most suitable irrigation methods for specific soil series. Findings highlight the remarkable efficiency of drip irrigation across various soil types, contrasting with the consistently lower performance of surface irrigation. The chapter emphasizes the significance of considering soil variability, evapotranspiration, and investment factors in selecting irrigation methods for …

Key Stages In The Growth And Maturity Of Field Pea, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Many farm operations rely on a clear understanding of the stage of crop development. This factsheet describes key growth stages of field pea, which will aid growers and their advisers in determining the appropriate timing for the application of herbicides, crop-topping, swathing, and harvest.

There is likely to be considerable variability in a crop, particularly at maturity and harvest. Therefore, it is often necessary to estimate the average or majority development stage of a crop. At first, this is best done numerically, but with experience it can be done by eye.

Button Grass And Its Management, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Button grass (Dactyloctenium radulans) is a native species found throughout Australia. It is a common summer weed species that depletes soil moisture and nutrients, reducing the yield potential of the subsequent crop. It also acts as a green bridge for crop pests and disease.

The rapid emergence and growth of button grass after rainfall makes it important for the Australian plague locust.

It can be a valuable pasture species in arid areas, although overgrazing of button grass can result in toxicity for sheep and cattle.

Survey Of Nematodes Associated With Strawberry In South Carolina And Evaluation Of Short-Term Heat Exposure On Nematode Reproduction Biology, Ivan A. Alarcon Mendoza

All Theses

Nematodes are a growing threat to the multi-billion-dollar strawberry industry in the US due to the lack of safe and effective management methods. Limited information on the distribution of nematodes in fumigated plasticulture strawberry fields further complicates their management. Additionally, climatic anomalies like rising soil temperatures and heat waves are occurring more often, and their impact on crop growth and nematode reproduction is not well understood. The current study was conducted with two main objectives: i) understand distribution and population densities of nematodes associated with plasticulture strawberry production in South Carolina, and ii) understand the impact of short-term high heat …

I’M A Forest, Not A Saltmarsh, Captain: Carbon And Sap Flow Dynamics In Coastal Forested Wetlands Of The Southeastern United States, Chris Shipway

All Theses

Coastal forested wetlands are identified as some of the highest-priority ecosystems for climate change mitigation. Here, we present two studies conducted in these unique ecosystems.

The first assessed changes in aboveground vegetative C stocks along the estuarine-riverine gradients of the Winyah Bay in South Carolina and the Savannah River in Georgia, using a space-for-time substitution to increase understanding of the impacts to upper estuarine forested wetlands from relative sea level rise. Standing C stocks on the Savannah River averaged 183.6 Mg C ha^-1, while sites on the Winyah system averaged 162.3 Mg C ha^-1. The largest …

Assessing Even Flat-Fan Nozzles For Spot Spray Herbicide Applications, Thiago H. Vitti

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

Herbicide efficiency in row-crop agriculture can be improved using precision technologies for controlling weeds and minimize agronomic, economic, and environmental impacts. Site-specific weed management technologies, such as spot-sprayers, allow herbicides to be sprayed only where weeds are present in the field. Understanding application parameters and their influence on weed control for site-specific spot-spray applications is essential. This research involved laboratory and greenhouse studies to investigate the coverage and coefficient of variation (CV) of even flat-fan spray nozzles under different spot-spray application scenarios, as well as the effect of weed size and application method on the control of various weed species …

Identifying Genes Linked To Variation In Metabolic And Whole Plant Phenotypes Using Data From Genome Resequencing, Transcriptomics, And Metabolic Profiling Of A Field-Grown Maize Diversity Panel, Ramesh Kanna Mathivanan

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

Maize metabolism is highly complex and influenced by genetic variation, yet the specific genes contributing to this variation and their links to non-metabolic traits remain less understood. To address this knowledge gap, we identified genes involved in maize metabolic variation and linked them to non-metabolic traits. We utilized a quadruplicate dataset of whole genome resequencing, transcriptomic, metabolic, and whole plant phenotype data from a single common field experiment of 660 diverse maize inbred lines. Leaf samples were collected shortly before flowering and analyzed using GC-MS for 26 metabolites. A Resampling Model Inclusion Probability Genome-Wide Association Study (RMIPGWAS) of approximately 2.6 …

Virion Composition Of Wheat Streak Mosaic Virus (Wsmv) And Its Use As An Expression Vector, Sourav Pal

Department of Plant Pathology: Dissertations, Theses, and Student Research

Wheat (Triticum aestivum L.) is the principal cereal grown in the United States, whose production ranks third in the world. Bacterial leaf streak (BLS) disease caused by Xanthomonas translucens pv. undulosa (xtu) is an emerging threat to wheat production in the Great Plains region of the United States of America. In this study, we engineered sequences encoding several plant-based antimicrobial peptides (AMP) were engineered into the WSMV genome and examined their effect on BLS disease in wheat infected by WSMV harboring AMP sequences. Out of nine AMPs, wheat expressing Ace-AMP1, PDF13, TK-AMP-D1, and TK-AMP-D3 produced resistance against the …

Transforming Grassland Conservation: Challenges And Opportunities Across Law, Policy, And Human Dimensions, Conor D. Barnes

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

Great Plains social-ecological systems are facing growing pressure from complex, ‘wicked’ problems. Addressing these problems will require integrating ecological resilience and complex systems thinking concepts into our legal framework in order to better reflect the changing ecological reality of the Great Plains and promote flexibility and adaptability in the face of that change. In this dissertation, I examine how past and present policy priorities have affected social-ecological systems on the Great Plains, and how ecological resilience and complex systems thinking might be applied to grassland management policy. In Chapter 2, I examine the rapid progress made in the adoption of …

Integrating Water And Nitrogen Management For Sustainable Agriculture: Optimizing Resource Use Efficiency And Maximizing Crop Productivity, Jiaming Duan

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

Advisors: Derek Heeren and Daran Rudnick Maize, accounting for over 95% of national grain production in the United States, is highly sensitive to water and nitrogen (N) inputs. Conventional agricultural practices often lead to excessive application, causing groundwater contamination through nitrate leaching. Therefore, there is a demand for integrating water and nitrogen management with innovative scheduling methods for sustainable agricultural development.

This dissertation first reviewed two decades of U.S.-based research, highlighting the optimal management of water and N to enhance yield, water use efficiency (WUE), and nitrogen use efficiency (NUE). Findings indicate that maintaining optimal levels of N and water …

Dynamics Of Soybean Seed Protein And Oil Content With Depth In The Canopy, Hafith Furqoni

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

Understanding the physiological basis of variation in seed composition is critical for optimizing soybean seed composition. Also, studying dry matter accumulation and nitrogen uptake, partitioning, and redistribution in soybeans is crucial due to its direct impact on seed yield levels and overall plant productivity. This study aimed to test the primary proxy influencing seed protein and oil content, which is their accumulation rate determined by the assimilate supply per seed. The second objective was to comprehensively understand soybean dry matter (DM) accumulation and nitrogen (N) uptake, partitioning, and removal patterns within the canopy. Field experiments were conducted using two soybean …

Assessing, Restoring, And Centering Social–Ecological Relationships For Advancing Social–Ecological Resilience In The Northern Great Plains Grasslands, Katia Pilar Carranza Bernal

School of Natural Resources: Dissertations, Theses, and Student Research

The Northern Great Plains grasslands are social-ecological systems that were shaped by evolutionary and Indigenous social-ecological relationships. European colonization disrupted many of these interactions, including the coupling of fire and grazing, and degraded social-ecological resilience, shifting these grasslands to a new state. For those reasons, my research focused on assessing, restoring, and centering evolutionary and Indigenous social-ecological relationships for advancing social-ecological resilience in the Northern Great Plains grasslands. I first performed a study in the Nebraska Sandhillls assessing the potential of patch-burn grazing to support grassland resilience by comparing its effects to those of rotational grazing. Through vegetation and bird …

Integration Of Matlab And Machine Learning To Accelerate Evaluation Of Biological Activity In Agricultural Soils And Promote Soil Health Improvement Goals, Andrew Stiven Ortiz Balsero

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

Traditionally, assessments of soil biological activity have been confined to laboratory settings, creating a disconnect with practical in-field methods. To bridge this gap, cotton fabric degradation has been used to illustrate soil microbial activity under different management practices. While effective, these demonstrations are subjective and labor-intensive.

Researchers have explored using image processing software like ImageJ and Adobe Photoshop to streamline this process. Although these tools accurately quantified fabric degradation under varying soil conditions, the methods remained labor-intensive and complex. Consequently, these methods were still not ideal for on-farm use by agricultural practitioners.

To further address labor and complexity limitations, the …

Soil Additives And Alternative Crops For Drought Defense In The Intermountain West, Tina M. Sullivan

All Graduate Theses and Dissertations, Fall 2023 to Present

The Western U.S. looks for water optimization and conservation as agriculture is the largest water diverter, and resources are pressured by urban growth, winter snowpack instability, and drought persistence. Agricultural producers have several potential options to optimize water use with different investments associated with them. Options with varying levels of risks and known management practices include alternative crops, soil wetting agents, and crop biologicals.

An alternative crop that grew incredibly fast in popularity was industrial hemp (Cannabis sativa) despite limited agronomic knowledge for best management practices. Field trials occurred (2020-2022) near Logan, UT to test a total of …

Environmental Physiology Of Medical Cannabis, F. Mitchell Westmoreland

All Graduate Theses and Dissertations, Fall 2023 to Present

Cannabis (Cannabis sativa L.) is increasingly being cultivated for industrial and medical uses. Medical cannabis is grown for cannabinoids and terpenes, compounds that continue to show promising therapeutic potential. Cannabidiol (CBD) and delta-9- tetrahydrocannabinol (Δ9-THC) are the two most common cannabinoids, but more than 150 have been identified in cannabis. The 2018 Farm Bill federally legalized cannabis containing less than 0.3% THC and high-THC medical cannabis is legal in 38 states. There is a need to understand environmental effects on yield and quality to ensure safety and quality for medical use.

The cultivation of medical cannabis is centered around …