- (Focus Area) Pest Management
- Author: Kathy Keatley Garvey
It's the birthday anniversary of noted entomologist Richard "Doc" Bohart (1913-2007), founder of the Bohart Museum of Entomology, University of California, Davis.
So when the Bohart Museum hosts a public open house (theme:"Museum ABCs: Arthropods, Bohart and Collecting") from 1 to 4 p.m., Saturday, Sept. 28, plans also call for a tribute to him and his work.
"Doc" Bohart founded the insect museum in 1946 and served as its first director; compiled 32 years on the entomology faculty; and became an internationally recognized entomologist and author.
Born Sept. 28, 2013 in Palo Alto, Richard began collecting butterflies at age 7. "He and his brother George 'Ned' Bohart collected butterflies for a local collector to earn pocket money," according to UC Davis distinguished professor emerita Lynn Kimsey, who directed the Bohart Museum for 34 years until her retirement on Feb. 1, 2024.
Bohart attended UC Berkeley, receiving three degrees in entomology culminating in his doctorate in 1938. He joined the UC Davis faculty in 1946 and chaired the Department of Entomology from 1956 to 1965. He taught general entomology, medical entomology, systematics, and agricultural entomology.
According to the Academic Senate's memorial, Bohart "contributed substantially to the world literature of the insect Order Hymenoptera, which included two landmark books, Sphecid Wasps of the World (with A. S. Menke), and The Chrysidid Wasps of the World (with L.S. Kimsey), as well as 230 journal articles and four other books on wasps and mosquitoes, including the second and third editions of The Mosquitoes of California (the second with Stanley B. Freeborn and the third with Robert K. Washino). During his career, he described more than 200 new species and genera of insects."
Today the Bohart Museum is the home of a global collection of eight million insects; a live petting zoo (including Madagascar hissing cockroaches, stick insects and tarantulas); and an insect-themed gift shop, stocked with T-shirts, hoodies, jewelry, books, posters, and collecting equipment. The new director, only the third since 1946, is Professor Jason Bond, the Evert and Marion Schlinger Endowed Chair in Insect Systematics, UC Davis Department of Entomology and Nematology, and associate dean of the UC Davis College of Agricultural and Environmental Sciences.
"His teaching and collecting activities resulted in the development of one of the finest collections of stinging wasps in the world in the Bohart Museum of Entomology," Kimsey said. "A great deal of this material was obtained through his collecting and that of his students. During his tenure, the museum collection grew from 500 specimens to 7 million, a span of some 60 years. Chancellor James Meyer dedicated the entomology museum in his name in 1983. The R. M. Bohart Museum moved into a new building in 1994 and was dedicated by Chancellor Larry Vanderhoef."
Open House. The open house, free and family friendly, will include "an overview of terrestrial arthropods which encompasses everything from insects, arachnids, millipedes, isopods and centipedes," said Tabatha Yang, education and outreach coordination. "We will also showcase some of the trapping/catching methods we use, for example, nets, lights, pitfall traps and malaise traps."
Pinning, spreading and curation demonstrations are planned "so people know how to take care of and preserve a dead arthropod for research or for a personal collection," Yang said. "People sometimes find a dead dragonfly or a butterfly on the ground and we often get asked how they can preserve it."
"We also get asked a lot of questions about our own collection and why the specimens don't decay," she added. "We will highlight the different curation techniques from pinning, point mounting, preserving in alcohol and mounting on slides."
Entomologist Jeff Smith, curator of the Lepidoptera collection, which encompasses some 750,000 specimens, will demonstrate and discuss the various steps of relaxing, pinning, spreading, and labeling moths and butterflies.
A Bohart volunteer since 1998, Smith has spread the wings of some 180,000 moths and butterflies, typically 6,000 or more each year for the past 30-plus years. He has crafted and donated some 2,475 wooden specimen drawers, including 110 so far this year. He also has donated some 100,000 specimens (primarily butterflies, moths but a few other insects, including beetles) to the Bohart Museum.
- Author: Kathy Keatley Garvey
YSP is a six-week summer residential program that introduces several dozen high-achieving high school students to original research within the fields of biological, agricultural, environmental, or the natural sciences.
The lab of nematologist Shahid Siddique, associate professor, UC Davis Department of Entomology and Nematology, mentored Anderson Van Wang, a 17-year-old senior at California City High School, Kern County, and Mason Walline, now 18, and a senior at Harvard-Westlake School, Los Angeles.
Anderson worked with doctoral student Veronica Casey of the Siddique lab to investigate the effects of bacterial supernatant to plant parasitic nematodes. Walline worked with Ching-Jung Lin, a doctoral student in the Siddique lab and the lab of Professor Gitta Coaker, Department to Plant Pathology, to transiently express nematode proteins in the plant system.
Also mentoring them were Siddique and lab members Bardo Castro Esparza, a postdoctoral fellow; and Alison Blundell, a doctoral candidate.
Each scholar receives five units of University Group Study Credit. All work is graded. Not only do they engage in university-level course work, attend lectures, and work on their projects, but they experience “the climate and culture of living and learning on a university campus,” according to YSP director Megan Bettis.
Mason won second-place honors in the research competition, the "YSP Summer Slam" (Elevator Pitch or short-version), competing with some 35 other students. His topic: “Advancing Transient Nematode Peptide Expression: A Pathway to Co-Immunoprecipitation Optimization." Said Lin: "He delivered a compelling two-minute presentation with a single slide. His expertise and professionalism were evident, and he was awarded second-place among the six finalists."
Neither plans a career as a nematologist, but what an amazing program and what an amazing experience.
“Working in Dr. Shahid Siddique's lab was an absolutely amazing experience," Anderson said.
“The lab environment was very high energy and upbeat," said Mason. "I'm so glad I was a temporary part of such a strong and inclusive community.”
And they learned a lot about nematodes.
Siddique defines plant-parasitic nematodes as "destructive pests causing losses of billions of dollars annually. Economic, health, and environmental considerations make natural host plant resistance a preferred strategy for nematode control, but there are limitations to this approach. In many cases, the resistance conferred by resistance genes is partial, and some of the nematodes are able to survive. Similarly, nematode resistance genes are often effective against only one or a few species, whereas plants are exposed to several pathogens in the field. Another concern is the emergence of pathotypes that can overcome resistance. In view of all these limitations, it is important to identify additional mechanisms and tools that can be used to develop novel and sustainable approaches to the management of nematodes."
The 2025 YSP summer program is set June 22-Aug. 2, with applications opening Jan. 15. High school students can apply at https://ysp-app.ucdavis.edu/.
- Author: Kathy Keatley Garvey
But agriculturists and scientists have.
The spotted-wing drosophila (SWD), Drosophila suzukii, is an agricultural pest that is super tiny.
It's approximately 2 to 4 millimeters in length with a wingspan of 5 to 6.5 millimeters. One millimeter is approximately 0.039 inches. There are 25.4 millimeters in 1 inch. So, the adult is about the size of a grain of sand, which can measure 0.5 to 2 mm in diameter.
SWD, native to southeast Asia and first discovered in California in 2008, lays its eggs in such soft-skinned, ripening fruits as strawberries, raspberries, cherries, blueberries, peaches, nectarines, apricot and grape.
In 2008, the first year of its discovery in California, the economic loss attributed to this pest amounted to $500 million. Latest statistics from 2015 indicate a $700 million national economic loss.
Lead author of the paper, “Transcriptome Analysis of Drosophila suzukii Reveals Molecular Mechanisms Conferring Pyrethroid and Spinosad Resistance,” is Christine Tabuloc, then a doctoral candidate and now a postdoctoral researcher working under the mentorship of Professors Chiu and Zalom.
"In this work, we leveraged high throughput sequencing to identify biomarkers of insecticide resistance in D. suzukii,” Tabuloc explained. “We found that different genes are responsible for resistance to different chemicals. Specifically, we found that genes involved in metabolism are highly expressed in flies resistant to pyrethroid insecticides. We also observed evidence of two different mechanisms of resistance in 2 lines generated from a single spinosad-resistant population. We found an increased expression of metabolic genes in one line and increased expression of cuticular genes in the other.”
Tabuloc added that “our work has enabled for the detection of resistance in California populations, and we are currently doing a nationwide screening to determine whether resistance is now present in other states. Currently, we are working with the Zalom lab to use the results of our assays to try and combat resistance. There are experiments in progress trying to increase the efficacy of insecticides by blocking some of the genes involved in resistance, such that the enzymes encoded by those genes have decreased function."
A giant in the entomological world, Zalom directed the UC Statewide Integrated Pest Management Program for 16 years. He is an Honorary Member of the Entomological Society of America (ESA), the highest ESA honor, and he served as its president in 2014.
“This work not only represents good science; it has very practical implications," Zalom said. He and Tabuloc presented results of the work at a special berry grower seminar on insecticide resistance organized by UC Agriculture and Natural Resources (UC ANR) Farm Advisor Mark Bolda, strawberry and caneberry farm advisor in Santa Cruz, Monterey and San Benito counties, Mark Bolda in Watsonville.
"The presentations were extremely well-received," Zalom noted. "The original program was targeted for about 1.5 hours, but the meeting extended to over three hours due to the extent of questions and great discussion that followed. Growers and their consultants are hungry for new information that they find interesting and potentially useful, and this work was clearly of interest to them.”
Said Bolda: “The research was top shelf and the need, of course, is very great. Some of the information that Frank and Christine presented has been put into immediate use in the industry.”
What most people don't know is that Bolda was the first to discover the pest in North America. That was in 2008.
"He asked me to come down to look at it and the problem...we weren't able to get an actual species identification until 2009!" Zalom said.
As the pest continues to spread throughout much of the country, anxious growers are worried about its increased resistance to pesticides. The UC Davis research team is alleviating that worry.
If you've noticed tiny, dark insects flying around your houseplants, you likely have fungus gnats. These tiny flies can be a nuisance indoors and may also damage your plants.
Fungus gnats lay their eggs in moist soil and their larvae feed on plant roots and decaying organic matter. Because of this, the key to managing fungus gnats is to let the soil dry out in between watering and don't overwater plants. Water plants from the bottom using saucers under pots. This keeps the top of the soil dry, discouraging fungus gnats.
Sticky traps can be placed in pots or near plants to catch fungus gnat adults. This is also a great way to monitor for fungus gnats. Pesticides, including several biological pesticides like Bacillus thuringiensis subspecies israelensis (Bti), are available to control fungus gnats. However, the best way to control fungus gnats is by simply adjusting watering practices.
To learn more about fungus gnats and their management, visit Pest Notes: Fungus Gnats.
- Author: Kathy Keatley Garvey
The seminars begin Monday afternoon, Sept. 30 and continue every Monday through Dec. 2.
Nematologist Amanda Hodson, assistant professor of soil ecology and pest management, is coordinating the seminars. All, except one, will be held in Briggs Hall. All, but one, will be on Zoom.
The Zoom link:
https://ucdavis.zoom.us/j/95882849672.
Michael Hoffmann, professor emeritus, Cornell University, will deliver the Thomas and Nina Leigh Distinguished Alumni Award Seminar in the Putah Creek Lodge at 4 p.m. on Oct. 14. (See below)
The list of seminars:
Monday, Sept. 30, 4:10 to 5 p.m., 122 Briggs
Kyle Wickings
Department of Entomology, Cornell University
Title: “Composition and Function of Soil Invertebrate Communities in Residential Greenspaces”
Monday, Oct. 7, 4:10 to 5 p.m., 122 Briggs
Juliana Rangel Posada
Professor of Apiculture, Department of Entomology, Texas A&M University
Title: “Don't Compromise: Food Lipid Content Shapes Protein-Lipid Regulation in Honey Bee (Apis mellifera) Nurses”
Monday, Oct. 14, 4 p.m. to 7 p.m. Thomas and Nina Leigh Distinguished Alumni Award Seminar
Michael Hoffmann
Professor Emeritus, Cornell University
Title: “Our Changing Menu: Using the Power of Food to Confront Climate Change”
This will take place beginning at 4 p.m. in the Putah Creek Lodge and will include a social, lecture and dinner. Reservations closed. (See more)
Monday, Oct. 21, 4:10 to 5 p.m.,122 Briggs
Andrew Corbett
Research Affiliate, UC Davis Department of Entomology and Nematology (formerly with the lab of UC Davis distinguished professor Jay Rosenheim, now emeritus)
Title: "In Silico Experiments with the Effect of Natural Habitats on Biological Control in Agricultural Landscapes."
Monday, Oct. 28, 4:10 to 5 p.m., 122 Briggs
Jolene Saldivar
UC Davis Chancellor's Postdoctoral Fellow, lab of Professor Louie Yang
Title: "Disturbance in Coastal Sage Scrub and the Implications for Migratory Butterflies”
Monday, Nov. 4, 4:10 to 5 p.m., 122 Briggs
Eliza Litsey (exit seminar)
Litsey, a former graduate student in the honey bee lab of Elina Niño, UC Davis Department of Entomology, received her master's degree in entomology in June 2024 and is now a laboratory technician at the lab of research entomologist Julia Fine, USDA/ARS, Davis. Litzey also holds a bachelor's degree from UC Davis.)
Monday, Nov. 18, 122 Briggs (in-person only; will not on Zoom)
Andre Custodio Franco
Assistant Professor, Indiana University Bloomington
Title: "Deciphering the Soil Macrobiome: Belowground Communities Driving Ecosystem Responses to Global Change”
Monday, Nov. 25, 4:10 to 5 p.m., 122 Briggs
Christine Sprunger
Associate Professor of Soil Health at Michigan State University
Title: "Nematodes as Bioindicators of Soil Health and Climate Resiliency”
Monday, Dec. 2, 4:10 to 5 p.m., 122 Briggs
Inga Zasada
Research Plant Pathologist, USDA-ARS
Title: "How an Applied Nematolgist Uses Genomic Tools to Address Plant-Parasitic Nematode Research”
For more information, contact Hodson at akhodson@ucdavis.edu