Enter researcher Paulo Vieira, a plant pathologist, molecular biologist and nematologist with USDA's Agricultural Research Service (USDA-ARS), Beltsville, MD.
He will speak on "Beech Leaf Disease: An Emergent Threat to Beech Forest Ecosystems in North America" at a virtual seminar hosted by the UC Davis Department of Entomology and Nematology, announced host and nematologist Shahid Siddique. It is set for 4:10 p.m., Wednesday, May 17. The Zoom link:
"The beech leaf disease nematode, Litylenchus crenatae mccannii, is recognized as a newly emergent nematode species that causes beech leaf disease (BLD) in beech trees (Fagus spp.) in North America," Vieira says in his abstract. "Since the first report of BLD on Fagus grandifolia in Ohio in 2012, the disease has rapidly spread to other states and Canada. This nematode has been so far reported in Pennsylvania, New York, Connecticut, Massachusetts, Maine, Michigan, Rhode Island, New Jersey, West Virginia, and Virginia, as well as Ontario. Leaf symptoms include swelling and darkening of interveinal tissues as well as chlorosis, while tissue necrosis and leaf curling occur at later stages of the disease. As a result, mortality of nematode infected understory beech trees has been reported after several years of infection in the United States. The fast dissemination of this nematode can impose a dramatic effect on beech forest ecosystems and natural diversity in North America."
Vieira says that "Little information on the molecular and cellular interaction between this nematode and its hosts is available. To advance our understanding into this unknown host- nematode system, we investigated the cytological aspects of this interaction using bright-field and scanning electron microscopy. Our data reveal that these nematodes can induce morphological changes in both bud and leaf tissues, which so far seem unique in the Nematoda phylum. These cellular changes ultimately provide the necessary nutrients for completion of the nematode life cycle, while dramatically affecting bud and leaf morphology. In addition, we used Illumina mRNA sequence analysis of a mixed stage population to obtain insight into the transcriptome of this nematode. Gene comparative analyses were combined to select a list of candidate effector/parasitism genes. Spatial expression of transcripts within the esophageal glands of L. crenatae mccannii by in situ hybridization validated a list of pioneer effectors novel to this species and across the Nematoda phylum. These analyses provide additional data for understanding the mode of parasitism of this newly emergent plant-parasitic nematode."
Vieira, who joined USDA-ARS in November 2021, holds a master's degree (2007) in plant pathology, phytopathoogy from the University of Évora, Portugal, and a doctorate (2012 in plant pathology, plant-nematode interaction from the University of Nice Sophia-Antipolis and Institute Sophia Agrobiotech, France. His resume includes postdoctoral researcher at the University of Évora (2012-2013) and USDA (2013-2015). Vieira served as a researcher in molecular biology at Virginia Tech for eight years before joining USDA-ARS in Beltsville.
Vieira's current research interests:
- Identification and functional analyses of effectors of plant-parasitic nematodes
- Genomics and transcriptomics of plant-parasitic nematodes, with a particular focus on migratory nematodes
- Plant-nematode interaction studies using cell and molecular biology approaches
Department seminar coordinator is urban landscape entomologist Emily Meineke, assistant professor. For technical issues regarding Zoom connections, she may be reached at firstname.lastname@example.org. (See complete list of spring seminars.)
First report of the beech leaf disease nematode Litylenchus crenatae mccannii (Nematoda: Anguinidae) in Michigan (Plant Disease journal, Nov. 22, 2022)
Paulo Vieria: Google scholar and Twitter accounts
His seminar is set for 4:10 p.m., Wednesday, April 12 in 122 Briggs Hall. It also will be virtual. The Zoom link:
"Parasitic infections, pesticide exposures, and lack of nutrition are thought to interact to cause synergistic declines in honey bee health," Mayack says in his abstract. "First, I will demonstrate how disease can lead to altered behavior that is linked to the honey bee‚ a highly social nature that results in its inability to buffer against energetic stress. Then I will discuss how environmental chemical exposure biomarker profiles (fingerprints) can be used to predict presence of the most common honey bee diseases and how the two are likely interact along metabolic pathways, which is likely to be key in explaining the underlying mechanisms responsible for synergistic declines in honey bee health."
"Lastly, I will present how a systems biology approach coupled with long term monitoring of bee health will be a central powerful tool, moving forward, for unraveling the mystery that surrounds identifying the specific mechanistic causes of global bee health declines."
"Honey bees pollinate $15 billion worth of crops in the United States each year, including more than 130 types of fruits, nuts, and vegetables," according to USDA-National Agricultural Statistics Service (NASS). "Honey bees also produce honey, worth about $3.2 million in 2017."
New Scientist featured Mayack in its April 28, 2021 edition in an article headlined: "Honeybees Stress Each Other Out by Warning about Minor Parasites."
"A one-celled fungus called Nosema ceranae can infect the guts of individual bees, causing a disease called nosemosis," wrote science journalist Christa Lesté-Lasserre. "Similar to tapeworm infections in humans, nosemosis apparently makes bees hungrier and reduces their resistance to pesticides and probably viruses, but it isn't particularly fatal. Yet, nosemosis is one of the top reasons honeybee populations are declining."
Mayack, then of Swarthmore College, Pennsylvania, "suspected this might have something to do with how the fungus affects the bees' social structures," she wrote.
Mayack, who joined the USDA-ARS in August of 2022, holds a bachelor's degree in biology (2007) from the State University of New York, Geneseo, and a doctorate in zoology (2012) from Colorado State University. He wrote his dissertation on “Behavioral Alteration in the Honeybee Due to Parasite-induced Energetic Stress.” Mayack served as a 2012-2014 Alexander von Humboldt Postdoctoral Fellow at the Zoology Institute, Martin-Luther-University Halle-Wittenberg, Germany.
His research interests include systems biology, improving honey bee health, animal physiology, animal behavior, parasite-host interactions, neurobiology, effects of aging, evolution of social behavior, regulation of appetite and energetic homeostasis, and metabolomics/exposomics.
Seminar coordinator Emily Meineke, urban landscape entomologist and assistant professor, has lined up these seminars for the spring quarter. For technical issues (Zoom), contact Meineke at email@example.com.
Research molecular biologist Dana Nayduch of the Agricultural Research Service, U. S. Department of Agriculture (USDA-ARS), will speak on "Can Surveying Microbial Communities of House Flies Help Us Understand Emerging Threats to Animal and Human Health?" at 4:10 p.m., Wednesday, March 1 in 122 Briggs Hall, Kleiber Hall Drive, UC Davis campus.
Her lecture also will be virtual. The Zoom link:
Nayduch, based in Manhattan, Kansas, will be introduced by her colleague, medical entomologist-geneticist Geoffrey Attardo, assistant professor, UC Davis Department of Entomology and Nematology.
"Dana is doing very cool work with house flies and looking at how bacteria in the fly are trading antibiotic resistance genes among themselves," said Attardo. "It's an interesting and scary system as antibiotic resistance is so high due to antibiotic usage in livestock rearing."
"House flies (Musca domestica L.) are ubiquitous, cosmopolitan pests inhabiting urban, rural and agricultural environments throughout the world. In these habitats acquire microbes from septic substrates that are used for feeding and reproduction, Nayduch says in her abstract. "Flies subsequently harbor and disseminate these microorganisms which may pose a risk to human and animal health. Our research characterizes and analyzes microbial communities of house flies using culture-based and molecular approaches in order to better understand their roles in the transmission of important bacterial disease agents and/or antimicrobial resistance. Because the microbial communities within house flies represent a snapshot of the microbes found in their local habitat, we also gain valuable insight into existing and emerging microbial threats to humanand animal health through our surveys which can help in predicting and preventing disease."
A pre-seminar coffee will take place from 3:30 to 4:10 in 158 Briggs.
Dana received her bachelor's degree in animal science from Rutgers University and her doctorate in zoology from Clemson University, where she studied house flies as vectors for pathogens. She served as a postdoctoral fellow at Yale University School of Public Health, working on molecular-genetic studies of tsetse flies. She then joined Georgia Southern University (GSU) as an assistant professor of biology in 2004, advancing to associate professor in 2009. At GSU she received NIH-R15 funding to study house fly-microbe molecular interactions.
Active in the Entomological Society of America (ESA), Nayduch is the vice president-elect of the Medical, Urban and Veterinary Entomology (MUVE) Section. A peer reviewer for the Journal of Medical Entomology and an editorial board member and subject editor for Annals for ESA, she organized and edited the first special collection for Annals: “Filth Fly-Microbe Interactions."
The UC Davis Department of Entomology and Nematology's winter seminars are held on Wednesdays at 4:10 p.m. in 122 Briggs Hall. All are virtual. Urban landscape entomologist Emily Meineke, assistant professor, coordinates the seminars. (See schedule.) She may be reached at firstname.lastname@example.org for technical issues.
ACP they call it. A native of southern Asia, it was first detected it in the United States (Florida) in 1998.
ACP serves as a vector or carrier for the deadly citrus greening disease or Huanglongbing (HLB), a bacterial disease that infects and kills citrus trees.
"ACP arrived in Southern California in 2008 and has fully infested that region," according to the UC Statewide Integrated Pest Management Program. "HLB disease was first detected in Los Angeles in 2012."
You may remember when the equivalent of a five-alarm fire went off when the citrus greening disease was found in California. The California Department of Food and Agriculture (CDFA) sounded the alarm.
What's new in the research?
Research molecular biologist Michelle Heck of the USDA's Agricultural Research Service (USDA-ARS) in Ithaca, N.Y., will discuss "Challenge-Driven Innovation in Citrus Greening Disease Research" when she presents a virtual seminar hosted by the UC Davis Department of Entomology and Nematology at 4:10 p.m., Pacific Time, Wednesday, Feb. 16.
The seminar is open to all interested persons. The Zoom link is https://ucdavis.zoom.us/j/99515291076.
Heck, who focuses her USDA-ARS research on the discovery and characterization of insect vector-plant-pathogen interactions, serves as a lead scientist and research molecular biologist with the Emerging Pests and Pathogens Research Unit, located in the Robert W. Holley Center for Agriculture and Health, Ithaca.
The Asian citrus psyllid is a threat to America's citrus industry, according to a USDA Fact Sheet. "Burned tips and twisted leaves result from an infestation on new growth. Psyllids are also carriers of the bacterium that causes Huanglongbing (HLB) disease, also known as citrus greening disease, spreading the disease to healthy citrus plants. Citrus greening is one of the most serious citrus plant diseases in the world. Once a tree is infected, there is no cure."
"Research planning involves novel, exceptionally difficult, team research that is subdivided into multiple phases with agency stakeholders," Heck says. Her research "integrates developed knowledge into applied agricultural practices to create novel management strategies for vector-borne plant diseases and the insect vectors." She conducts her studies in support of the USDA-ARS NP 304 Action Plan: Crop Protection and Quarantine, Problem Statement 3A2, a systems approach to environmentally sound pest management.
Heck, who holds a bachelor's degree in biology from Boston University, received her doctorate from.Cold Spring Harbor Laboratory, Cold Spring, N.Y. She completed her postdoctoral training in vector biology and mass spectrometry-based proteomics. Her research on protein interactions and protein transport in plants and insects spans more than 20 years, resulting in an international reputation as a vector biology authority skilled in the management of vector-borne plant diseases. Heck is a lead in the USDA-ARS Citrus Greening Grand Challenge, the agency's coordinated national response to combat citrus greening disease and the agency's scientific representative on the National Cotton Council's Cotton Leafroll Dwarf Virus Task Force.
Heck has published more than 50 peer-reviewed journal articles, book chapters, and several patents. Her peers have recognized her scientific excellence with a number of awards, including a 2017 Presidential Early Career Award for Scientists and Engineers from the Obama White House Office of Science and Technology Policy.
For technical issues involving the seminar, contact Siddique at email@example.com.
- Asian Citrus Psyllid, UC Statewide Integrated Pest Management Program (UC IPM)
- Asian Citrus Psyllid and Huanglongbing Disease (UC IPM)
- Asian Citrus Psyllid Regulation and Quarantine Boundaries, California Department of Food and Agriculture (CDFA)
- Citrus Pest and Disease Prevention, CDFA
But thrips do pack a powerful punch.
A major pest of many agricultural crops, including lettuce, they damage plants by (1) sucking their juices and (2) transmitting viruses.
If you've been following the thrips damage in the lettuce production in the Salinas Valley, or want to know more about thrips, the UC Davis Department of Entomology and Nematology's virtual seminar on Wednesday, Jan. 20 should interest you.
Research entomologist Daniel Hasegawa of the Crop Improvement and Protection Research Unit, Agricultural Research Service, U. S. Department of Agriculture, will speak on "Landscape and Molecular Approaches for Managing Thrips and Thrips-Transmitted Viruses in the Salinas Valley" at the department's first seminar of the winter quarter.
The hour-long virtual seminar, via Zoom, begins at 4:10 p.m., announced agricultural Extension specialist Ian Grettenberger, seminar coordinator. To access the seminar, fill out this Google form link at https://bit.ly/3oWYjnt. (Contact Grettenberger at firstname.lastname@example.org.)
"In 2019-2020, lettuce production in the Salinas Valley of California was devastated by thrips-transmitted impatiens necrotic spot virus (INSV)," Hasegawa says in his abstract. "Due to the inherent challenges in managing thrips using conventional chemical tactics, and no direct means for managing the virus, there is a strong need for new management strategies."
This seminar, he says, will provide an overview of
- The challenges in managing thrips and INSV in lettuce production
- What we've learned about the epidemiology of thrips and INSV, and
- Opportunities to improve cultural practices and develop biotechnology tools, such as RNAi for managing thrips and INSV in the Salinas Valley.
Hasegawa joined the Salinas USDA-ARS team in May 2019 after serving as a postdoctoral research associate (molecular biology) for three years with the USDA-ARS in Charleston, S. C. He specializes in vector entomology, molecular biology and biotechnlogy. "My lab uses a variety of techniques to understand insect vector-virus relationships that impact plant health and agriculture," he says on Linked In. "We use molecular, genetic, and epidemiological concepts to understand drivers of vector-borne transmission of pathogens and utilize genetic technologies (e.g. RNAi and CRISPR), to improve agriculture productivity and sustainability."
Hasegawa received his bachelor of science degree in biochemistry in 2007 from UC Riverside and his doctorate in biology from Clemson University in 2013.
The mission of the Crop Improvement and Protection Research Unit is to improve germplasm of lettuce, spinach and melon, determine basic biology of viral, fungal and bacterial diseases affecting these crops, develop alternatives to methyl bromide as a soil fumigant for control of soilborne pests in strawberry and vegetables, reduce postharvest losses of lettuce, develop scientifically based organic crop production practices, and develop methods for control of weeds. (See more on the Pacific West Area website.)
"More than 90 percent of the lettuce sold in the United States is grown in California, and the majority of production from April through October occurs in the Salinas Valley, while production form November through March occurs in California's Imperial Valley," according to keepcaliforniafarming.org.
The UC Statewide Integrated Pest Management Program (UC IPM) says this about thrips: "Thrips, order Thysanoptera, are tiny, slender insects with fringed wings. They feed by puncturing the epidermal (outer) layer of host tissue and sucking out the cell contents, which results in stippling, discolored flecking, or silvering of the leaf surface. Thrips feeding is usually accompanied by black varnishlike flecks of frass (excrement). Pest species are plant feeders that discolor and scar leaf, flower, and fruit surfaces, and distort plant parts or vector plant pathogens. Many species of thrips feed on fungal spores and pollen and are often innocuous. However, pollen feeding on plants such as orchids and African violets can leave unsightly pollen deposits and may reduce flower longevity. Certain thrips are beneficial predators that feed on other insects and mites."
"Thrips can readily move long distances floating with the wind or transported on infested plants, and exotic species are periodically introduced," UC IPM notes./span>