Digital Commons Network^™

Weather Conditions Associated With Citrus Canker Incidence Caused By Aw Strain In The Lower Rio Grande Valley Of South Texas, Amit Sharma, Teresa Patricia Feria-Arroyo, George Yanev, Madhurababu Kunta

School of Integrative Biological & Chemical Sciences Faculty Publications

Citrus canker, caused by bacterium Xanthomonas citri subsp. citri (Xcc), affects the citrus industry by making the fruit unmarketable due to unsightly lesions on the fruit. Citrus canker caused by a relatively new AWstrain of Xcc was reported on the citrus trees in the residential areas of the Lower Rio Grande Valley (LRGV) of South Texas. Xcc AW has a limited host range, predominantly affecting limes and a few other citrus species. Previous work has reported prevailing environmental conditions that influence the incidence and spread of the citrus canker caused by the Asiatic A strain. However, no information is available …

Deep Learning-Based Quantification Of Tall Fescue Abundance In Pastures, Rose E. Binkley, Samuel R. Revolinski, Echo Elizabeth Gotsick, Ray Smith, Zeya Wang, Katsutoshi Mizuta

Plant and Soil Sciences Faculty Publications

Accurate and rapid measurement of tall fescue abundance is essential for efficient forage management and mitigating livestock exposure to potential endophyte-related toxicity. Traditional visual estimation methods are labor-intensive and are subject to change depending on the observer doing the calculations, which limits their scalability and consistency. This study explores the application of deep learning techniques to automate and improve the classification of tall fescue abundance across pasture systems in Kentucky. Ground-truth abundance classes were evaluated using one of the traditional methods with occupancy grid and compared against estimates derived from red-green-blue images. Two convolutional neural network architectures, YouOnlyLookOnce (YOLO) and …

Micronutrients (Trace Elements) For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Micronutrient deficiencies can result from removal of agricultural products over many years, changes in soil acidity, or from large increases in plant biomass production and export. This page is specific to high rainfall pastures (more than 600mm average annual rainfall) in the south-west of Western Australia.

The Department of Primary Industries and Regional Development recommends tissue testing to check plant micronutrient nutrient needs.

Potassium For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Potassium (K) deficiency can lead to a decline in clover content and severely limit pasture productivity in high rainfall pastures. Large amounts of potassium can be lost each year through leaching and removal of potassium in hay or silage.

This information is specific to high rainfall pastures receiving more than 600mm average annual rainfall in the south-west of Western Australia.

Soil Sampling High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Soil sampling and testing is an essential part of making good fertiliser decisions. Fertilisers are a large cost to farming pastures in high rainfall areas. This page is specific to sampling high rainfall pastures (more than 600mm average annual rainfall) in the south-west of Western Australia.

The Department of Primary Industries and Regional Development recommends soil sampling and testing as part of a plant nutrient management program.

Sulfur For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Sulfur deficiency can substantially reduce pasture yield on sandy soils, particularly in wet years where the sulfate form of sulfur leaches below the root zone of pasture plants, making it unavailable.

This information applies specifically to high rainfall pastures (over 600mm average annual rainfall) in the south-west of Western Australia.

The Department of Primary Industries and Regional Development recommends basing fertiliser decisions on good evidence (soil and tissue test results)

Tissue Sampling And Analysis For High Rainfall Pastures In Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

Tissue testing helps identify nutrient deficiencies that impact plant health. In high rainfall areas ( > 600 mm), pastures are highly productive and have greater demand for both macro- and micronutrients. Micronutrient status is best assessed through plant tissue, as soil levels are difficult to measure accurately.

The Department of Primary Industries and Regional Development recommends tissue testing to assess the effectiveness of fertiliser and soil testing programs, and diagnose emerging macronutrient and micronutrient deficiencies that could cause production losses.

Environmental Impact Of Nitrogen And Phosphorus Fertilisers In High Rainfall Pasture Areas Of Western Australia, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

The most commonly used nitrogen and phosphorus fertilisers in the high rainfall (>600mm annual average) south-west of Western Australia can be leached into the groundwater and washed into waterways, resulting in serious environmental and economic damage.

The Department of Primary Industries and Regional Development recommends regular soil testing and consultation with FertCare-accredited advisers to reduce leaching losses and increase profit from added nutrients.

Depth And Soil Physical Context Govern Soil Organic Carbon, While Woody Cover Moderates Native Vegetation Relationships In California Rangelands, Dabid Zuniga Garcia

Cal Poly Humboldt theses and projects

Soil organic carbon (SOC) is central to soil function and an important component of climate mitigation in rangeland ecosystems, but the controls on SOC across California’s working rangelands remain understudied. Using data from Point Blue Conservation Science’s Rangeland Monitoring Network, this study evaluated how soil properties, vegetation structure, and recent climate relate to SOC concentration at depths of 0–10 cm and 10–40 cm across 145 ranches spanning four California regions. Linear mixed-effects models showed that SOC was consistently higher in topsoil than subsoil and highest in coastal sites relative to interior valleys. Bulk density was the strongest negative predictor of …

Impact Of Cross-Client Heterogeneity In Federated Learning For Real-World Plant Disease Classification, Ritesh Janga

All Graduate Theses, Dissertations, and Other Capstone Projects

Deep learning applications are being adopted in agricultural image analysis that include challenges of data privacy and limited institutional data and heterogeneity of different types of architectures. However, Federated Learning is a model that allows collaborative training on data that does not have to be shared among parties. Therefore, Federated Learning is an effective method of collaborative training; however, its comparative effectiveness as compared to individual (local) training on diverse architectures has never been examined in an agricultural context. The objective of this study was to examine Federated Learning for the purpose of crop disease classification on extreme non-IID distributed …

A Conserved Ethylene-Triggered Cell Death Mechanism May Underlie Hollow Stem Formation Across Plant Species, Mengxiao Yan, Weijuan Fan, Yinghui Meng, Jiamin Zhao, Wei Yang, Ziyin Xu, Yusen Gao, Haiyan Zhuang, Wuyu Zhou, Yuqin Wang, Qingjun Huang, Ling Yuan, Hongxia Wang, Jun Yang

Plant and Soil Sciences Faculty Publications

Hollow stems have independently evolved multiple times across the plant kingdom and play crucial roles in plant development and various environmental adaptations. However, the mechanisms underlying stem hollowness remain poorly understood. Water spinach (Ipomoea aquatica) is one of the few hollow-stemmed plants in the Convolvulaceae family (eudicot: asterid), and its hollow stems are essential for thriving in aquatic environments. Using histochemical staining and transcriptome analysis, we found that programmed cell death (PCD) is involved in cavity formation at water spinach shoot tips. Single-cell and spatial transcriptome analyses further revealed that ethylene and reactive oxygen species (ROS) likely drive …

Supplemental Bibliographic Details. From 2001 Mars Odyssey To Earth’S Climate Crisis: Integrating Gamma Spectroscopy, Martian Soil Simulants, And Plant Genomes For Agroecology, Anchored In Sri Lanka’S Mars-Context Serpentinites, Suniti Karunatillake, Maheshi Dassanayake, Carlos Gary Bicas

Planetary Science Lab

Bibliographic details follow to supplement hyperlinked citations in the multinational GANGOTRI-supporting project conceived by Karunatillake, Dassanayake, and Gary-Bicas

Differential Growth Dynamics Of Common Salt Marsh Species Spartina Alterniflora And Juncus Roemerianus Under Varied Sediment Amendments, Caitlin Hemphill, Richard P. Hale, Erik S. Yando

Biological Sciences Faculty Publications

Introduction

Many coastal wetlands are at high risk of degradation or loss due to sea‐level rise. Restoration techniques for maintaining coastal marshes are paramount, with thin‐layer placement (TLP) emerging as one feasible solution. Despite TLP's utilization, additional research is needed on species‐ and sediment‐specific responses.

Objectives

Our research combines greenhouse and field experimentation to test species and sediment composition responses aimed at maximizing vegetation while maintaining increased elevation.

Methods

The greenhouse experiment used two common marsh plants, Spartina alterniflora and Juncus roemarianus. Five centimeters of sediment (mud, sand, and sand/mud mix) was added, and subsequent sediment and vegetation metrics …

Land Use Influences Dissolved Organic Matter Composition In The U.S. Coastal Critical Zone Network, Aleksandar I. Goranov, Elizabeth V. Whitney, Brian R. Moyer, Katherine L. Tully, Patrick G. Hatcher, Yu-Ping Chhin

Chemistry & Biochemistry Faculty Publications

Coastal watersheds are highly productive biogeochemical systems supporting robust coastal fisheries and contributing significantly to the marine gross primary production flux. These ecosystems are comprised of civil infrastructure, farms, forests, and marshes, and their diversity is reflected in the quantity and quality of dissolved organic matter (DOM). Here, we assess the role of farming in influencing DOM from surface waters of six coastal tidal creeks adjacent to forest and farm sites in the US Critical Zone Network. Molecular fingerprinting using electrospray ionization - Fourier transform - ion cyclotron resonance - mass spectrometry revealed that farm-influenced DOM was enriched in nitrogen-, …

Impacts Of Management Practices And Soil Properties On Free-Living Nitrogen Fixation In Eastern South Dakota, Laura Galvan Nuevo

Electronic Theses and Dissertations

Free-living nitrogen (N) fixation (FLNF) may represent a sustainable pathway to supplement crop N demand in agroecosystems, yet edaphic and management factors regulating this process under field conditions remain poorly understood in the Northern Great Plains. Using 15N2 direct method to quantify potential FLNF (pFLNF) and baseline FLNF (bFLNF), this thesis investigates how crop rotations (2-, 3-, and 4-year systems), tillage management (conventional vs. no-till), cover cropping, and soil properties affect the potential of free-living diazotrophs to supply N via FLNF in a long-term no-till corn-based system in Southeastern South Dakota. A two-year field study evaluated pFLNF across four growing …

A Simple Statistical Tool To Correct The Daily Temperature Effect On Dielectric Soil Matric Potential Sensor Readings, Sebastián Bravo Peña, Meindert Commelin, Ole O. Wendroth

Plant and Soil Sciences Faculty Publications

High-resolution time series recorded by soil water dielectric sensors are often affected by other processes. Dielectric soil matric potential sensors, such as the TEROS 21, exhibit temperature sensitivity, resulting in deviations of readings from the true value due to soil temperature fluctuations. However, methods for correcting this effect remain limited. The objective of this study was to create a straightforward, scale-based statistical approach to mitigate the influence of daily temperature oscillations on matric potential dielectric readings. The temperature sensitivity correction function (TSCF) identifies, quantifies, and smooths diurnal fluctuations caused by soil temperature dynamics. We provide a detailed description of the …

Evaluating Source Material And Seed Propagation Techniques For Spartina Alterniflora To Enhance Salt Marsh Restoration In Coastal Georgia, Maygan Palacios

College of Graduate Studies: Theses & Dissertations

Salt marshes provide critical ecosystem services, including carbon sequestration, flood attenuation, and habitat for diverse aquatic and terrestrial species. Despite their ecological importance, these habitats are increasingly threatened by anthropogenic activities and rising sea levels. To protect and restore salt marshes and their ecosystem services, restoration efforts using living shorelines (LS) have become more common. Along the Eastern and Gulf coasts of the United States, the native grass Spartina alterniflora is commonly used in LS installations for its key role in salt marsh food webs, resilience to abiotic stress, and ability to stabilize and build sediment. Previous studies have documented …

Using L1-Magic For Feature Enhancement And Reduced Redundancy In Hyperspectral Data, Ashley Alfred

Mathematics Dissertations

Hyperspectral imaging offers detailed spectral information, but achieving high spatial resolution typically requires large and expensive equipment. This study explores an alternative approach: enhancing low-quality hyperspectral bands using an L1-norm minimization technique known as L1-magic. The goal is to improve the utility of low-cost hardware by preserving discriminative features, promoting sparsity, and reducing spectral redundancy. We apply L1-magic to enhance low-quality bands and hypothesize that this method selectively amplifies key features while suppressing redundant information. Experimental results indicate that the enhanced bands approach the quality of high-resolution data, enabling robust feature extraction without reliance on high-end hyperspectral cameras.

Field-Scale Evaluation Of Satellite- Derived Vegetation Indices And Image Timing For In-Season Nitrogen Management In Corn, Ana Morales-Ona, Katsutoshi Mizuta, James J. Camberato, Robert Nielsen, Yuxin Miao, Davide Cammarano, German Mandrini, Daniel Quinn

Plant and Soil Sciences Faculty Publications

Introduction: Traditional methods to determine the agronomic optimum nitrogen rate (AONR) for corn (Zea mays L.) rely on grain yield data, limiting in-season decision-making for nitrogen (N) management. Vegetation indices (VIs) derived from satellite imagery can serve as proxies for grain yield and help estimate in-season AONR, enabling timely sidedress applications. This study aimed to (1) quantify how VI–yield relationships vary during the vegetative period across fields with different tillage systems and crop residue; (2) determine whether VI–N response curves can be used to estimate AONR (AONRvi); and (3) assess the accuracy of AONRvi relative to yield-based AONR (AONRy). …

Ovipositional Behavior Of The Twig Girdler (Cerambycidae: Oncideres Cingulata) On Stems Of Mockernut Hickory (Carya Tomentosa) In Arkansas, R. Tumlison, L. Serviss

Journal of the Arkansas Academy of Science

The Twig Girdler (Cerambycidae: Oncideres cingulata) is a long-horned beetle that girdles stems of certain species of trees to prepare a habitat for its offspring. The stems eventually die, break, and fall from the tree, but the beetle usually had already laid its eggs within the stems. Eggs are laid singly, almost always at growth rings or leaf bases. Because the space for the young to develop is finite, laying too many eggs could cause reproductive failure and too few eggs would be suboptimal. We hypothesized that the female laying eggs should be able to evaluate the stem and …

Rate Response Of Curlyleaf Pondweed And Native Plants To Flumioxazin In Minnesota Lakes, Pearl J. Jensen

All Graduate Theses, Dissertations, and Other Capstone Projects

Curlyleaf pondweed (Potamogeton crispus L.) is an invasive aquatic plant present across the United States that causes significant recreational issues, outcompetes native plant species, and depletes water quality. Before senescing in mid-summer, curlyleaf pondweed forms a large number of turions that can lay dormant in the sediment for several years. Typical herbicide management of this species occurs in early spring to target the plant before turion production occurs and while native plants are dormant. Flumioxazin has shown potential in curlyleaf pondweed management in small scale studies, but its effects have not been assessed in operational management. In this study, treatments …

Climate Change Effects On Biomass And Greenhouse Gas Emissions Are Ameliorated By Nontoxic Endophytes In Southeastern Usa Transition Zone Tall Fescue Pastures, Rebecca Kay Mcgrail, Jonathan D. Moore, A. Elizabeth Carlisle, Jim A. Nelson, Rebecca L. Mcculley

Plant and Soil Sciences Faculty Publications

Background: The plant–microbe interaction between tall fescue and its endophyte Epichloë coenophiala can affect ecosystem responses to changing rainfall patterns and increasing temperatures. Endophyte-infected (E+) stands often exhibit improved stress tolerance and differing soil greenhouse gas (GHG) emissions compared to endophyte-free (E−) stands. However, it is unknown if mammalian nontoxic endophyte (NTE) strains introduced into some tall fescue cultivars confer differing stress tolerances or reduce soil GHG emissions.

Methods: We quantified the impact of fescue-NTE symbioses in Jesup and Texoma on biomass and GHG emissions in response to increased temperature (+3°C) and altered precipitation (50% lengthened interval between events) using …

A Global Synthesis Of Fragipan Silicon Concentrations And Relationships With Soil Physicochemical Properties As A Function Of Soil Parent Materials, Christopher Shepard

Plant and Soil Sciences Faculty Publications

Fragipans are dense, brittle subsurface horizons that restrict root growth and limit water-holding capacity. A common factor in these soils is a binding agent, potentially either phyllosilicate clay bridging, amorphous aluminosilicate/silica, or silica sorbed to Fe oxides. Others have suggested that no binding agent is present within these soil horizons and that the arrangement of individual particles is solely responsible for these horizons. In this article, a secondary data synthesis was utilized to demonstrate that silicon (Si) accumulation is a key pedogenic process in loess-derived fragipan horizons, but not in all fragipans. The average dithionite-extractable Si (Si_d) content …

Hydroponics In The Classroom: Cultivating Plants, Captivating Young People, Stacy A. Adams, Christian Stephenson, Theresa James, Kim Todd

Department of Agronomy and Horticulture: Faculty Publications

Few students take the initiative to pursue coursework beyond that required for progression to graduation. Limited are opportunities that connect educational content to industry application, potentially inspiring young people towards impactful careers. The United States government has emphasized the importance of STEM education to ensure national security and to maintain economic competitiveness globally. STEM education is not a defined discipline but an approach for building knowledge through application and engagement. Developing and managing a hydroponics prototype provides numerous opportunities for embedding STEM content into a fun and interactive project. This poster provides inspiration for constructing a simple deep water culture …

Assessment Of Soybean Response To Irrigation Variability In Eastern Nebraska Using The Aquacrop Model, Anmol Singh, Saleh Taghvaeian, Yufeng Ge, Derek M. Heeren, Frank Bai

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Soybean [Glycine max (L.) Merr.] is a major irrigated crop in eastern Nebraska, where recent expansions in irrigated agriculture and projected trends in irrigation demand necessitate thorough investigations of approaches that can optimize its irrigation management. In this study, the AquaCrop model was calibrated and validated using 19 variable irrigation treatments from a five-year field experiment. The model accurately simulated canopy cover, soil water content, and grain yield, with validation normalized root mean square error (nRMSE) of 12%, 7%, and 7%, respectively. The model was subsequently applied to estimate soybean yield and water requirement during a 15-year period (2010–2024) …

Evaluating Planting Methods For Native Seed Production And Exploring Granivory In The Northern Great Plains, Allison Dollen

Electronic Theses and Dissertations

Temperate grasslands have faced immense losses due to land use change in the last 150 years and less than half of the overall grasslands that once covered North America remain today. A portion of historic and remaining U.S. grasslands are located within the northern Great Plains (NGP) region which is home to over 1,600 species of native plants and provides many ecosystem services and economic benefits. Initiatives to restore grasslands and their ecosystem services are currently underway, but barriers such as limited native seed supply and granivory hinder restoration efforts. My first chapter addresses knowledge gaps in planting methods for …

A Comparative Analysis Of The Ecophysiology Between The Invasive Macroalgae Starry Stonewort And The Native Macroalgae Chara To Predict Invasion Potential, Thomas J. Zellmer

All Graduate Theses, Dissertations, and Other Capstone Projects

Starry stonewort (Nitellopsis obtusa) is an invasive macroalga from Eurasia. Currently, starry stonewort’s invasive range consists of the upper Midwest and Great Lakes region, including the Mississippi River. Starry stonewort poses recreational and ecological problems by forming dense canopies that extend through the water column. Starry stonewort occupies a late-season niche space with dense biomass occurring in late July and persisting well into autumn. There is a lack of information on the ecophysiology of starry stonewort. In this study, two populations of starry stonewort, Minnesota and New York, were analyzed to compare regional differences in ecophysiology, along with chara (native …

Succession And Alpine Plant Habitat Of A Recently Deglaciated Foreland In The Trinity Alps, California, Sebastian Evans

Cal Poly Humboldt theses and projects

The recent extinction of the Salmon Glacier in the Trinity Alps, California, provides a rare opportunity to examine post-glacial succession in a region of high endemism experiencing climatic stress. Using a chronosequence spanning ~150 years since deglaciation, I investigated (1) vegetation successional trajectories in the foreland, (2) whether the foreland functions as a climate refugium for alpine specialists, and (3) whether facilitative interactions between the dominant vascular plant (DVP) and bryophytes occur and persist through succession. I surveyed 100 plots across 11 transects within the foreland and 40 randomized plots in adjacent ecosystems. Successional patterns and refugial potential were analyzed …

Urban Trees In The Urban Hydrology Cycle, Jorge R. Vera

Theses, Dissertations and Capstones

In urban forestry, trees provide numerous economic, ecological, and aesthetic benefits to the surrounding community. One of their key roles is intercepting stormwater runoff, reducing flooding risk, and improving water quality. Chapter 1 of this thesis characterized the ecological and economic contributions of urban trees on the Marshall University campus and provides guidance on their management and conservation in the future. Chapter 2 examined how urban tree species modify the urban hydrology cycle by altering the volume and timing of precipitation delivery. In Chapter 1, we inventoried 114 acres of Marshall University's main campus in Huntington, WV, from June 28 …

Aquatic Invasive Species Survey And Treatment On Lake Umatilla And Lake Celilo 2024-2025 Report, Jacob Rose, Gabriel E. Campbell

Center for Lakes and Reservoirs Publications and Presentations

Flowering Rush (Butomus umbellatus) is an invasive aquatic plant in the Pacific Northwest that threatens salmon habitat. The Center for Lakes and Reservoirs staff surveyed for this and other aquatic species from 2024 and 2025 in the Columbia River in Lake Umatilla and Lake Celilo. This document summarizes their survey efforts including their protocols, data, and small-scale removal efforts.