Plant Pathology Commons^™

The Importance Of Communication Skills To Independent Crop Consultants, Lindsay Overmyer

Doctor of Plant Health Program: Dissertations and Student Research

Independent crop consulting companies provide services to farmers by scouting (i.e., collecting field observations of plants and pests) and developing management recommendations for individual fields. In production agriculture, independent crop consultants (ICCs) are professionals who are independent of product sales. They are knowledgeable in many disciplines including plant pathology, entomology, weed science, plant science, economics, water management, and soil science. However, ICCs must also have extensive communication skills to communicate to their audience of field scout(s), farmers, industry professionals, and government officials. The goal of this document is to examine how ICCs use their communication skills and how they can …

Mancha Anular Necrótica Y Mancha De Verano Del Césped, Claudia Nischwitz, Kelly Kopp, Jaydee Gunnell, Kent Evans, Erin Frank, Celina Wille

All Current Publications

La mancha anular necrótica y mancha de verano del césped son enfermedades fúngicas que infectan los pastos de estación fría y causan síntomas similares. Los síntomas comienzan como un crecimiento deficiente y marchitez de las hojas, que se convierten en parches marrones obvios que varían de 1 a 3 pies de diámetro. Debido a los síntomas similares que se observan en la infección por ambos patógenos, se necesita un microscopio para diagnosticar adecuadamente cada enfermedad. El manejo de ambas enfermedades puede ser difícil y frecuentemente requiere una combinación de técnicas de control cultural, químico y varietal.

Proceedings Of The 48th Annual Meeting, Southern Soybean Disease Workers (March 3, 2021, Virtual Content), Tessie Wilkerson, Trey Price, Tom W. Allen, Burton H. Bluhm, Danise Beadle

Southern Soybean Disease Workers: Conference Proceedings

2021 Southern Soybean Disease Workers Agenda

Virtual | Wednesday, March 3, 2021

Southern United States Soybean Disease Loss Estimates for 2020. TW Allen, K Bissonnette, CA Bradley, JP Damicone, NS Dufault, TR Faske, T Isakeit, RC Kemerait, A Koehler, D Langston, JD Mueller, GB Padgett, PP Price, EJ Sikora, IM Small, L Thiessen, and H Young

Student papers (Tessie Wilkerson, moderator)

Secondary metabolites produced by Xylaria necrophora are responsible for the foliar symptoms associated with taproot decline of soybean. Teddy Garcia-Aroca, Trey Price, José Solórzano, David Galo, Sophie Sheffield, Jonathan K. Richards, and Vinson P. Doyle

Meta-analysis of fungicide performance …

Assessment Of Grain Safety In Developing Nations, Jose R. Mendoza

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Grains are the most widely consumed foods worldwide, with maize (Zea mays) being frequently consumed in developing countries where it feeds approximately 900 million people under the poverty line of 2 USD per day. While grain handling practices are acceptable in most developed nations, many developing nations still face challenges such as inadequate field management, drying, and storage. Faulty grain handling along with unavoidably humid climates result in recurrent fungal growth and spoilage, which compromises both the end-quality and safety of the harvest. This becomes particularly problematic where there is little awareness about health risks associated with poor …

Boxwood Dieback: Molecular Detection, In-Vitro Fungicide Efficacy, And Host Susceptibility For Managing A New Emerging Disease Caused By Colletotrichum Theobromicola, Harleen Kaur

LSU Master's Theses

Boxwood (Buxus spp. L) is one of the most common and widely planted perennial ornamentals in both home gardens and commercial landscapes. Grown for its evergreen, dark green foliage, boxwood cultivation dates back to 4000 BC in Egypt. Although considered hardy, boxwood is susceptible to several plant pathogens. Recently reported boxwood dieback, a fungal disease caused by Colletotrichum theobromicola, has been spreading at an alarming rate within the United States. Boxwood dieback consists of symptoms that resemble to those caused by Phytophthora root rot, Volutella blight, and some abiotic disorders and can be easily misdiagnosed in nurseries and …

Mechanisms Of Silencing Suppression By A Polerovirus P0 Protein, Natalie Holste, Hernan Garcia-Ruiz

School of Biological Sciences: Presentations

Maize lethal necrosis is an intense viral disease spreading across sub-Saharan Africa. Maize is the staple crop grown in sub-Saharan Africa, but most crops infected with maize lethal necrosis will not survive to harvest. This causes immense economic hardship and starvation within the population. Maize lethal necrosis consists of a combination of two viruses, Maize chlorotic mottle virus (MCMV) and a virus from the genus potyvirus. In a recent study, a Maize yellow dwarf virus-RMV (MYDV-RMV)-like polerovirus, was repeatedly detected in plants with maize lethal necrosis. Poleroviruses have a silencing suppressor, P0 protein, and the mechanism of suppression is poorly …

Diversity, Function And Regulation Of Cell Surface And Intracellular Immune Receptors In Solanaceae, Jong Hum Kim, Christian Castroverde

Biology Faculty Publications

The first layer of the plant immune system comprises plasma membrane-localized receptor proteins and intracellular receptors of the nucleotide-binding leucine-rich repeat protein superfamily. Together, these immune receptors act as a network of surveillance machines in recognizing extracellular and intracellular pathogen invasion-derived molecules, ranging from conserved structural epitopes to virulence-promoting effectors. Successful pathogen recognition leads to physiological and molecular changes in the host plants, which are critical for counteracting and defending against biotic attack. A breadth of significant insights and conceptual advances have been derived from decades of research in various model plant species regarding the structural complexity, functional diversity and …

Proceedings Of The 47th Annual Meeting, Southern Soybean Disease Workers (March 4-5, 2020, Pensacola Beach, Florida), Burton H. Bluhm, Carl Bradley, Tom W. Allen, Danise Beadle, Trey Price

Southern Soybean Disease Workers: Conference Proceedings

Contents

Southern United States soybean disease loss estimates for 2019. TW Allen, K Bissonnette, CA Bradley, JP Damicone, NS Dufault, TR Faske, T Isakeit, RC Kemerait, A Koehler, HL Mehl, JD Mueller, GB Padgett, PP Price, EJ Sikora, IM Small, L Thiessen, and H Young

Abstracts of presented papers

Fungicide efficacy on target spot in Tennessee soybean. Ty Smith, H Kelly, and Z Hansen

Temporal dynamics of Neohydatothrips variabilis, Frankliniella tritici, and Frankliniella fusca in South Central Wisconsin and the occurrence of Soybean vein necrosis virus. Cristina Zambrana-Echevarria, S Kaplan, RL Groves, and DL Smith

Population distributions and …

Virus-Induced Changes In Nuclear Proteins And Membranes In Nicotiana Benthamiana Cells, Caleb Mathias

Theses and Dissertations--Plant Pathology

Viruses rely on host proteins to complete their life cycles. This results in alterations to normal cell physiology to processes which benefit viral processes such as replication and movement to other cells. This may involve the relocalization of host proteins away from their original subcellular targets to sites which may benefit the virus, a process that is not as well understood as it relates to the nucleus. To identify nuclear proteins that may be involved in such processes, a library of random Nicotiana benthamiana cDNAs were expressed as GFP fusions in a transgenic marker lines expressing a histone 2B:RFP nuclear …

Improving Kentucky's Winter Wheat And Double Crop Soybean Rotation, Katherine Susan Rod

Theses and Dissertations--Plant and Soil Sciences

The winter wheat double crop soybean rotation is an economically viable rotation for Kentucky farmers. Recent decreases in commodity prices has warranted the need to evaluate intensive management practices that can increase yields and profitability in this crop rotation. There were three goals of this dissertation: 1.) identify management practices that would decrease deoxynivalenol (DON) in harvested wheat grain and increase wheat heading and anthesis uniformity, 2.) evaluate double crop soybean planting timing and identify intensive management practices to increase seed yield, and 3.) determine the profitability of these management options. These studies were conducted in Princeton KY between 2016 …

Arthropod Resistant Tomatoes: Screening Tools, Yield And Nutritional Quality Of Interspecific Hybrids, Mohammad Hasan Salman Ali Dawood

Theses and Dissertations--Plant and Soil Sciences

Tomato (Solanum lycopersicum) is one of the most economically important vegetable crops grown around globe but is a host for numerous pests and pathogens. In the future, tomato breeders will have to focus on increasing fruit quantity and on enhancing pest resistance. Many accessions of the wild relative of tomato, S. habrochaites display high levels of resistance towards arthropods such as spider mites. The presence of the sesquiterpene hydrocarbon, 7-epi-zingiberene, found in S. habrochaites type IV trichomes has been associated with arthropod resistance. However, the presence of other compounds in its trichome secretions may also be related …

Evaluation Of Pheromone Mating Disruption For California Red Scale Control In Commercial California Citrus, Joel Timothy Leonard

Master's Theses

California red scale (CRS), Aonidella aurantii, is an increasingly injurious insect pest for the California citrus industry due to insecticide resistance, changing weather patterns, and shifting trade regulations. The presence of the insect on fruit, damages the rind of the fruit and high populations can cause dieback of branches as well as lower yields. Pheromone mating disruption of CRS has the potential to alleviate population control concerns and reduce insecticide use. The efficacy of the pheromone mating disruption technique for pest management of CRS was determined using the products CheckMate® CRS and Semios CRS Plus. CheckMate® CRS was evaluated …

Effects Of Sudangrass Cover Crop And Soil Solarization On Weed And Pathogen Management In Organic Strawberry Production, Timothy Jacobs

Master's Theses

Field and lab experiments were conducted to determine the efficacy of sudangrass (Sorghum X drumondii (Nees ex Steud.) Millsp. & Chase) cover crop management techniques and soil solarization on important agricultural weeds and pathogens in organic strawberry production in Central California. Lab experiments assessed the time needed to kill weed seeds at temperatures typically achieved during soil solarization (40°C, 45°C, 50°C, 55°C, and 60°C) in California. Seeds tested included little mallow, redstem filaree, bristly oxtongue, annual sowthistle, common purslane, nettleleaf goosefoot, and redroot pigweed. Efficacy of simulated …

Rust And Viral Mosaic Diseases In Biofuel Switchgrass, Anthony A. Muhle

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

Switchgrass (Panicum virgatum L.) is a perennial warm-season monocot that is indigenous to locations in North America east of the Rocky Mountains, and is considered a model grass for biofuel feedstock production. As switchgrass production increases, diseases pose a potential threat to biomass production and ethanol extraction. The two predominant switchgrass diseases in Nebraska are rust caused by Puccinia spp. and a viral mosaic disease caused by Panicum mosaic virus (PMV) and its associated Satellite panicum mosaic virus (SPMV). In this thesis, one study determined how SPMV affects PMV infection and systemic spread in two populations of switchgrass at different …

Meta-Analysis Of Yield Response Of Foliar Fungicide-Treated Hybrid Corn In The United States And Ontario, Canada, Kiersten A. Wise, Damon Smith, Anna Freije, Daren S. Mueller, Yuba Kandel, Tom Allen, Carl A. Bradley, Emmanuel Byamukama, Martin Chilvers, Travis Faske, Andrew Friskop, Clayton Hollier, Tamra A. Jackson-Ziems, Heather Kelly, Bob Kemerait, Paul Price Iii, Alison Robertson, Albert Tenuta

Plant Pathology Faculty Publications

Background

Foliar fungicide applications to corn (Zea mays L.) occur at one or more application timings ranging from early vegetative growth stages to mid-reproductive stages. Previous studies indicated that fungicide applications are profitable under high disease pressure when applied during the tasseling to silking growth stages. Few comprehensive studies in corn have examined the impact of fungicide applications at an early vegetative growth stage (V6) compared to late application timings (VT) for yield response and return on fungicide investment (ROI) across multiple locations.

Objective

Compare yield response of fungicide application timing across multiple fungicide classes and calculate the probability …

Evaluation Of Host Resistance And The Utilization Of Organic Amendments To Manage Macrophomina Crown Rot Of Strawberry In California, Jonathan W. Winslow

Master's Theses

The production of strawberries can be severely limited by soilborne plant pathogens, insects and weeds. Macrophomina phaseolina is a problematic soilborne fungal pathogen in California strawberry production inciting the disease Macrophomina crown rot. When established, the pathogen can cause extensive plant decline and mortality. Host resistance will be a critical tool for managing this disease and guiding breeding programs in the post methyl bromide era. Evaluation of host resistance in strawberry germplasm to M. phaseolina was evaluated through phenotypic assessments of disease incidence. A total of 90 strawberry cultivars and elite selections were included in a replicated field trial conducted …

Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson

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

Seedling disease is one the most economically important diseases of soybean in the United States. It is commonly caused by Fusarium spp., Rhizoctonia solani, Pythium spp., and Phytophthora sojae, alone, or together as a disease complex. Fungicide seed treatments continue to provide the most consistent management of seedling diseases. Soil-applied protoporphyrinogen oxidase (PPO) inhibitor herbicides are used preemergence in soybean production to manage several broadleaf weeds. Applications of PPO-inhibitors can result in phytotoxic injury to soybean when environmental conditions are not favorable for soybean growth. These environmental conditions can favor seedling disease development as well. In this thesis, two …

Reporting Charcoal Rot In Chia And Developing A Susceptibility Assay, Reis M. Misaka, Hagop S. Atamian Dr., Julien Besnard Dr.

Student Scholar Symposium Abstracts and Posters

Chia (Salvia Hispanica) cross breeds were planted in the summer of 2018 with the intent of selective breeding for agricultural benefit. Preexisting pathogens in the soil caused 40-50% fatality of adult plants. This was surprising due to the precursory knowledge that chia has antibiotic and antifungal oils (Elshafie et. al. 2018); chia was only recently documented to be susceptible to Fusarium wilt (Fusarium oxysporum). The primary pathogen responsible was identified as Macrophomina phaseolina (aka charcoal rot); a widespread soilborne pathogen which has multiple commercial hosts (Su et. al. 2001).

M. phaesolina on wheat seed vector where used as …

Dna Barcoding Of Pratylenchus From Agroecosystems In The Northern Great Plains Of North America, Mehmet Ozbayrak

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

Pratylenchus species are among the most common plant parasitic nematodes in the Great Plains Region. The objectives of this study were to barcode Pratylenchus specimens for species identification in the Great Plains region using mitochondrial CO1 DNA barcode. In order to (1) determine species boundaries, (2) assess the host associations of barcoded Pratylenchus, (3) to determine the distribution patterns across the Great Plains Region and, (4) to evaluate the species status of P. scribneri and P. hexincisus by a multivariate morphological analysis of haplotype groups identified by DNA barcoding. Soil samples, primarily associated with eight major crops, were collected …

Proceedings Of The 46th Annual Meeting Of The Southern Soybean Disease Workers (March 6-7, 2019, Pensacola Beach, Florida), Carl Bradley, Heather M. Kelly, Burt Bluhm, Danise Beadle, Patricia Bollich, Trey Price, Tom Allen

Southern Soybean Disease Workers: Conference Proceedings

Contents

List of SSDW Officers

Agenda for March 6-7, 2019

Abstracts for presented/contributed papers

Evaluating phytotoxicity in response to fungicide by adjuvant combinations. TW Allen and TH Wilkerson

Effect of delayed harvest on the seed quality of commercial soybean cultivars. JC Rupe, JA Rojas, R Holland, SR Segalin, RD Bond, and JA Still

Virome of Macrophomina phaseolina isolates collected from soybean fields in Mississippi. Nina Aboughanem-Sabanadzovic, Tessie Wilkerson, Tom Allen, and Sead Sabanadzovic

Genomic evidence for interspecific hybridization in Cercospora cf. flagellaris strains associated with Cercospora leaf blight of soybean. Alex Zaccaron, Kona Swift, Ahmad Fakhoury, and Burt Bluhm

Identification …

Grapevine Vein Clearing Virus: Epidemiological Patterns And Construction Of A Clone, Cory Von Keith

Graduate Theses/Dissertations

Grapevine vein clearing virus (GVCV) is a recently discovered virus belonging to the Badnavirus genus. Characteristic to its name, the virus is associated with a disease where symptoms manifest as pronounced vein-clearing, resulting in severe berry deformation and vine decline in susceptible grape varieties. Sustainable production of wine is dependent on healthy plants. The associated disease is mainly found in Midwest vineyards. Attempts were made in this thesis to provide evidence of causality of the virus to the associated disease and to infer the historical path and migration pattern of GVCV. Conclusions and discussions will provide grape producers with the …

Breeding For Resistance In California Strawberry To Verticillium Dahliae, Zachary Christman

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

This article focuses on breeding resistant strawberries to the fungus Verticillium dahliae, common name Verticillium wilt. This is a serious fungal disease that can result in a loss of 50% or more of a strawberry harvest when grown in infested soil. The main goal is to provide an example of how a cultivar can be made more resistant to a plant pathogen with the use of plant breeding methods.

Since 1930 the University of California, Davis, has been developing strawberry cultivars that are adapted to the agricultural industry and regional farms. Developing cultivars that require fewer inputs are of …

Proceedings Of The 45th Annual Meeting Of The Southern Soybean Disease Workers (March 7-8, 2018, Pensacola Beach, Florida), Heather M. Kelly, Terry Spurlock, Carl Bradley, Danise Beadle, Patricia Bollich, Trey Price, Tom Allen

Southern Soybean Disease Workers: Conference Proceedings

Contents

List of SSDW Officers

Agenda for March 7-8, 2018

Abstracts for contributed/presented papers

Retrospective analyses regarding the impact of soybean diseases in the USA .TW Allen, PD Esker, and CA Bradley

Diaporthe (Phomopsis) species on soybean: current status in the United States. Febina Mathew, Kristina Petrovic, Lisa Castlebury, Tom Allen, Gary Bergstrom, John Bonkowski, Carl Bradley, James Buck, Emmanuel Byamukama, Martin Chilvers, Anne Dorrance, Nicholas Dufault, Loren Giesler, Nancy Gregory, Heather Kelly, Nathan Kleczewski, Trey Price, Dean Malvick, Sam Markell, Daren Mueller, Damon Smith, Terry Spurlock, Kiersten Wise, and Marina Johnson

New insights into the genetic underpinnings …

Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda

LSU Master's Theses

Aspergillus flavus is a saprophytic ascomycete that can also actively invade the seed of crops and potentially contaminate them with harmful aflatoxins. Management of A. flavus currently relies mostly on biocontrol. However, there is still a lot to learn about its biology and ecology so the current approach can be improved. An A. flavus population survey was undertaken during the fall of 2014 across eight Mississippi River states to determine population diversity and geographic distribution of VCGs. Isolates from corn and soil were also characterized for VCG, sclerotial morphotype, mating type, cyclopiazonic acid, and aflatoxin production in order to determine …

Proceedings Of The 44th Annual Meeting, Southern Soybean Disease Workers (March 8-9, 2017, Pensacola Beach, Florida), Terry Spurlock, Trey Price, Heather M. Kelly, Danise Beadle, Patricia Bollich, Tom Allen

Southern Soybean Disease Workers: Conference Proceedings

Contents

Agenda for March 8-9, 2017

Contributed papers

Soybean cyst nematode: current status, challenges and opportunities. G Tylka and K Bissonnette

Updates of the 2nd SCN (Soybean Cyst Nematode) Coalition. Albert Tenuta

Developing management zones for nematodes in soybean. C Overstreet, EC McGawley, DM Xavier-Mis, and M Kularathna

Microbial communities associated with long-term tillage and fertilizer management practices. AY Srour, J Hackman, RL Cook, JP Bond, and AM Fakhoury

Microbial profile of SDS-suppressive soils in soybean fields. AY Srour, LFS Leonardo, DK Malvick, JP Bond, and AM Fakhoury

Understanding the phytobiome; using strip trials and spatial analysis to determine concomitant …

The Lx Report Of The Bean Improvement Cooperative No. 60, March 2017.

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

CONTENTS

LX Annual Report of the Bean Improvement Cooperative xi

BIC Coordinating Committee Membership - 1957 to 2017 . xii

BIC Meritorious Service and Distinguished Achievement Award Recipients - 1957 to 2015 xiii

BIC Awards Nomination Request for 2017 xvi

BIC/NAPIA Meeting in 2017 . xix

In Memory of Guillermo E. Galvez-Enriquez xx

RESEARCH PAPERS FOR 2017

OPTIMIZING SPORULATION OF Pseudocercospora griseola IN VITRO • Paula F. de Pádua1, Rafael Pereira1, Luanna B. W. Gomes1 and Elaine A. de Souza1* 1

FINE MAPPING THE BROAD SPECTRUM ANTHRACNOSE RESISTANCE GENE IN AMENDOIM CAVALO 3 • Gilio, T.A.S.1, Oscar P. Hurtado-Gonzales2, Giseli …

Towards The Development Of A Sustainable Soya Bean-Based Feedstock For Aquaculture, Hyunwoo Park, Steven Weier, Fareha Razvi, Pamela A. Peña, Neil A. Sims, Jennica Lowell, Cory Hungate, Karma Kissinger, Gavin Key, Paul Fraser, Jonathan Napier, Edgar B. Cahoon, Thomas Clemente

Center for Plant Science Innovation: Faculty Publications

Soya bean (Glycine max (L.) Merr.) is sought after for both its oil and protein components. Genetic approaches to add value to either component are ongoing efforts in soya bean breeding and molecular biology programmes. The former is the primary vegetable oil consumed in the world. Hence, its primary usage is in direct human consumption. As a means to increase its utility in feed applications, thereby expanding the market of soya bean coproducts, we investigated the simultaneous displacement of marine ingredients in aquafeeds with soya bean-based protein and a high Omega-3 fatty acid soya bean oil, enriched with alpha-linolenic …

Exploration Of Chemical And Biological Management Strategies For Diaphorina Citri The Primary Vector Of Candidatus Liberibacter Asiaticus, Gretta Marie Sharp

Biology Theses

Diaphorina citri (Hemipteran: Psyllidae), the Asian citrus psyllid, is a phloem-feeding, invasive species endemic to southern Asia that was first identified in the United States in Florida in 1998. Since introduction, D. citri has spread across the major citrus growing regions of the United States. This is of great concern to the citrus industry because D. citri is the primary vector of Candidatus Liberibacter asiaticus the causal agent of Haunglongbing (HLB). Haunglongbing is the most economically devastating disease of citrus causing an estimated 8.92 billion dollars lost in revenue and 4.62 billion dollars lost in gross domestic product between 2006-2007 …

A Brief History Of Corn: Looking Back To Move Forward, Jon Derek Pruitt

Doctor of Plant Health Program: Dissertations and Student Research

Maize was domesticated from teosinte in Mexico some 7,000 to 10,000 years ago and quickly spread through the Americas. It has become one of the most important crops at a local and global level. Two types, Northern Flint corn and Southern Dent corns provided the basis of the genetic background of modern maize hybrids. The development of hybrids, first double-cross and later single-cross hybrids, along with a transition to high input farming provided huge yield increases, which have continued to improve with improving technology.

Increase in maize production also caused a rise in Western corn Rootworm (Diabrotica virgifera virgifera …

Managing Drought Stress In California Agricultural Systems, Gregory D. Brittain Jr.

Doctor of Plant Health Program: Dissertations and Student Research

California is currently facing a historic drought, and this has led many farmers in the state to severely cut back on irrigation. Optimal use of water for irrigation requires a comprehensive understanding of how plants respond physiologically to water stress (Chapter 1). By monitoring water requirements in crops and managing irrigation to meet those requirements, growers can significantly reduce water use (Chapter 2). This can be done through improving application efficiency of irrigation technology as well as increasing the water use efficiency of the crops themselves. Deficit irrigation practices can be used to manipulate the physiology of water use in …