- Author: Kathy Keatley Garvey
Her seminar also will be virtual. The Zoom link:
https://ucdavis.zoom.us/j/95882849672. Host is community ecologist Rachel Vannette, associate professor, UC Davis Department of Entomology and Nematology.
"Infectious disease prevalence is among the top five drivers of global extinction, including in wild bees," the bee biologist says in her abstract. "With the global decline of wild bees, our work aims to contribute to understanding how community characteristics shape infectious disease prevalence in plant-pollinator communities. Infectious parasites can influence host immunity, physiology, and reproduction. The sharing of floral resources is a common mode of disease transmission among pollinators."
"Increasing host aggregation on floral resources can increase disease prevalence, that is, amplification," Ponisio noted. "Conversely, high host species diversity---even if accompanied by host aggregation---may dilute infection. Because bees pick up parasites from flowers, but not all flowers transmit parasites equally, flower abundance and diversity may further contribute to parasite dilution. In three systems, mass-blooming sunflower in Yolo County, CA, harvested forests in Coast Range, OR, and high elevation meadows across the Southwestern U.S., I examine how the factors that shape plant-pollinator abundance and diversity and the ramifications for parasite prevalence in wild bee communities. Across all systems, more than 40% of bees have at one parasite. Both natural (phenology) and human-induced (years post-harvest, mass-blooming crops) modification of the bee and floral communities indirectly affected parasitism by altering host community characteristics. I found a consistent amplification effect of host (bee) abundance and detected dilution through either host diversity or floral diversity in each system."
On her website, Ponisio elaborates: "We focus on understanding the mechanisms by which species interactions maintain species diversity, and how we can harness these processes to manage and restore diversity in human-modified systems. We focus on pollinators because they are critical for pollination in managed and natural plant communities, but our research is broadly applicable across ecological interactions. Our aim to discover new insights into how communities form, evolve, and persist through time and space, aiding in the prediction and prevention of community collapse. We combine modeling, synthesis and field-based work, and adhere to the principles of reproducible, open science."
Lauren, who grew up in Fresno, holds a bachelor's degree in biology, with honors, in ecology and evolution (2010) from Stanford University, and her master's degree in biology (2011) from Stanford. She received her doctorate from the Department of Environmental Science Policy and Management, UC Berkeley, in 2016.
She conducted postdoctoral research at UC Berkeley and served on the faculty at UC Riverside before accepting her current position. She received graduate fellowships from the National Science Foundation and the National Institute for Food and Agriculture, as well as a postdoctoral fellowship from the Berkeley Institute for Data Science. She was named among the Global Food Initiative's “30 Under 30” in Food Systems in 2016.
Ponisio says one of her most difficult field work experiences occurred in Yosemite National Park, according to her People Behind the Science podcast. "Their study on the effects of fires on pollinators required them to backpack out to remote sites where there had been natural fires. Lauren started working months ahead of time to get ready for the trip and prepare dehydrated meals for the lab to eat. One day, they opened the large canister where they had been storing their food to protect it from bears, and they discovered the food was gone. All that was left was a handwritten note from someone thanking them for leaving out food."
"The next day, the lab's field assistant tripped over a log and sprained her ankle. Then they accidentally left their sampling gear at a site and had to hike all the way back to retrieve it. Later, a bear came into their campsite and destroyed many of the traps they needed to collect pollinators for their study. At this point, Lauren and her colleagues were exhausted, surviving on snacks, their field assistant could barely walk, and much of the equipment they needed had been destroyed. In the face of all of these challenges, Lauren stayed calm. These kinds of things happen in field research, and everyone made it back to share the story."
Ponisio was featured on National Public Radio's "All Things Considered" in January of 2021 when she discussed "Wildfires Open Forests for Wildlife and Research."
Ponisio is the lead author of a recently submitted journal paper, "Mass-Flowering Crops Attract Bees, Amplifying Parasitism," co-authored by G. P. Smith, H. Sardinas, J. Zorn, Q. S. McFrederick and S. H.Woodard. (See CV)
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. They are coordinated by urban landscape entomologist Emily Meineke, assistant professor. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.
- Author: Kathy Keatley Garvey
The event, set Saturday, Feb. 18, will showcase 11 museums or collections on campus. It's free and family friendly.
Donors can help support the project by accessing the site. Their donation can be in honor of someone or in memory of someone.
Eleven museums or collections on campus will showcase their work:
- Anthropology Museum, 328 Young Hall and grounds, noon to 4 p.m.
- Arboretum and Public Garden, Habitat Gardens in the Environmental GATEway, adjacent to the Arboretum Teaching Nursery on Garrod Drive, 9 a.m. to 1 p.m.
- Bohart Museum of Entomology, Room 1124 and main hall of the Academic Surge Building, Crocker Lane, 9 a.m. to noon and 1 to 4 p.m.
- Botanical Conservatory, the greenhouses along Kleiber Hall Drive, 11 a.m. to 3 p.m.
- California Raptor Center, 1340 Equine Lane, off Old Davis Road, 9 a.m. to 3 p.m.
- Center for Plant Diversity, Sciences Laboratory Building/Esau Science Hall, off Kleiber Hall Drive, 11 a.m. to 3 p.m.
- Nematode Collection, Sciences Laboratory Building/Esau Science Hall, off Kleiber Hall Drive, 9 am. to 3 p.m.
- Marine Invertebrate Collection, Sciences Laboratory Building/Esau Science Hall, off Kleiber Hall Drive, 9 am. to 3 p.m.
- Museum of Wildlife and Fish Biology, Room 1394, Academic Surge Building, 455 Crocker Lane, 10 a.m. to 2 p.m.
- Paleontology Collection, 1309 Earth and Physical Sciences Building, 434 LaRue Road, 12 noon to 4 p.m.
- Phaff Yeast Culture Collection, Robert Mondavi Institute Brewery and Food Processing facility, Old Davis Road, 10 a.m. to 2 p.m. (See news story)
The UC Davis Biodiversity Museum Day is traditionally held on Presidents' Day Weekend at various venues on campus. The 2022 event, however, took place March 6 in the UC Davis Conference Center and drew some 1000 visitors. This year, it's back home to the individual departments where scientists will be on hand to greet visitors and answer questions.
Organizers of the crowdfunding are Tabatha Yang, education and outreach coordinator for the Bohart Museum of Entomology; Brennen Dyer, Bohart Museum collections manager; and Melissa Cruz Hernandez, outreach and leadership program manager, UC Davis Arboretum and Public Garden.
"Your support will enable our 11 collections--the students, staff and faculty associated with them-- to hold this event," they announced. Donations will not only help us sustain this free science event, they will enable our student interns to take science outreach to a whole new level. The goal of our event is to connect people from all walks of life to science and the biodiversity surrounding them. All donors will be recognized on the Biodiversity Museum Day social media accounts with a shout-out post."
The donor wall is at https://crowdfund.ucdavis.edu/project/35545/wall. Gifts are tax-deductible.
- Author: Kathy Keatley Garvey
Her dissertation proposal also will be virtual. The Zoom link:
https://ucdavis.zoom.us/j/99327991233.
“In the proposed research, I will study the effectiveness of both automated precision spray applications and drone-mediated releases of biological control agents for the suppression of lettuce aphid and western flower thrips in several contexts," she says in her abstract. "I hope that the results of the proposed research will contribute to the development of best-use practices to guide the use of both technologies."
"I will generate novel data that fill existing knowledge gaps regarding the use of precision insecticide applications and drone releases of natural enemies in lettuce production systems. This will advance the adoption of these new pest management tools and contribute to a more sustainable integrative pest management system for lettuce."
Addie received her bachelor's degree in molecular environmental biology from UC Berkeley in 2011 and her master's degree in horticulture and agronomy from UC Davis in 2018. Before enrolling at UC Davis, she worked as a researcher under research chemist Spencer Walse at the USDA Agricultural Research Service (ARS) laboratory in Parlier, CA (2019-2021) and the UC Davis Contained Research Facility in Davis, CA (2012-2019), studying postharvest integrated pest management (IPM) of quarantine pests.
Active in the Entomological Society of America (ESA), Abrams received a second-place or runner-up award for her student research presentation at the 2022 ESA meeting, a joint meeting of the Entomological Societies of America, Canada, and British Columbia held in Vancouver, B.C., Nov. 13-16.
In her abstract, she noted that "Commercial lettuce production in California's central coast represents 70 percent of the production in the United States. Recent discoveries of some chemistries in ground and surface water in the Salinas valley region have placed the insecticidal chemistries used by the industry at risk of increased regulation. Automated thinner-sprayers use plant-detection sensors to apply chemical sprays directly to individual lettuce plants, so that the same amount of product to plants as a standard broadcast sprayer while potentially reducing the amount of pesticide applied per acre by up to 90 percent. Field experiments testing this technology for the control of western flower thrips (Frankliniella occidentalis) and aphids, lettuce-currant aphid (Nasovonia ribisnigri) and others, were conducted to compare the efficacy of automated sprays to a conventional broadcast application system. Experiments were conducted in conventionally managed organic romaine lettuce fields using a complete randomized block design. Prior to and at regular intervals after treatment, heads were sampled from experimental and control plots to assess pest pressure. Results from this experiment validate the use of the automated sprayers to apply insecticides for the control of aphid and thrips pests in lettuce and will be discussed in the context of developing best-use-practices for this technology."
At the 2019 Pacific Branch of ESA meeting, Abrams delivered a presentation on Rearing methods for brown marmorated stink bug, Halyomorpha halys, on live host plants. She has authored or co-authored several publications on stink bugs.
- Author: Kathy Keatley Garvey
And how do animals use changes in day length and temperature to adapt their physiology and behavior to seasonal environmental changes?
Those are the questions that UC Davis postdoctoral researcher Sergio Hidalgo Sotelo asked himself, and now newly published research that he spearheaded in the laboratory of molecular geneticist-physiologist Joanna Chiu—building on previous Chiu lab research--sheds more light on the topic.
The research article, “Seasonal Cues Act Through the Circadian Clock and Pigment Dispersing Factor to Control EYES ABSENT and Downstream Physiological Changes,” appears in the current edition of the journal Current Biology.
Sotelo, a Pew Latin American Fellow in the Biomedical Sciences fellow in the lab of Professor Chiu, vice chair of the UC Davis Department of Entomology and Nematology, collaborated with Chiu and two lab members: Christine Tabuloc, a doctoral candidate, and Maribel Anguiano, now a doctoral student in the UC Davis Neuroscience graduate program and a former member of National Institutes of Health Postbaccalaureate Research Education Program (PREP).
“This work,” Chiu said, “certainly helps us progress towards a more complete picture of how animal seasonality is regulated at the molecular and cellular level. Excitingly, it also raises many more interesting questions, which Sergio and our team cannot wait to answer.”
Their summary:
Organisms adapt to seasonal changes in photoperiod and temperature to survive; however, the mechanisms by which these signals are integrated in the brain to alter seasonal biology are poorly understood. We previously reported that EYES ABSENT (EYA) shows higher levels in cold temperature or short photoperiod and promotes winter physiology in Drosophila. Nevertheless, how EYA senses seasonal cues is unclear. Pigment-dispersing factor (PDF) is a neuropeptide important for regulating circadian output rhythms. Interestingly, PDF has also been shown to regulate seasonality, suggesting that it may mediate the function of the circadian clock in modulating seasonal physiology. In this study, we investigated the role of EYA in mediating the function of PDF on seasonal biology. We observed that PDF abundance is lower on cold and short days as compared with warm and long days, contrary to what was previously observed for EYA. We observed that manipulating PDF signaling in eya+ fly brain neurons, where EYA and PDF receptor are co-expressed, modulates seasonal adaptations in daily activity rhythm and ovary development via EYA-dependent and EYA-independent mechanisms. At the molecular level, altering PDF signaling impacted EYA protein abundance. Specifically, we showed that protein kinase A (PKA), an effector of PDF signaling, phosphorylates EYA promoting its degradation, thus explaining the opposite responses of PDF and EYA abundance to changes in seasonal cues. In summary, our results support a model in which PDF signaling negatively modulates EYA levels to regulate seasonal physiology, linking the circadian clock to the modulation of seasonal adaptations.”
Sotelo, who specializes in chronobiology (the study of biological rhythms), molecular genetics and biochemistry, won the 2021 Young Neuroscientist Symposium Award at the meeting of the Chilean Society for Neuroscience, Chile, and received a merit award for his presentation at the 2022 Society for Research on Biological Rhythms (SRBR) Biennial Conference in Amelia Island, Florida.
A native of Puente Alto, Santiago, Chile, Sotelo joined the Chiu lab as a postdoctoral fellow in the summer of 2020. He is one of 10 post-docs from across Latin America—including Argentina, Brazil, Chile, Mexico, Peru, and Uruguay—to receive two years of funding to conduct research. The fellows work under the mentorship of prominent biomedical scientists, including alumni of the Pew Scholars Program in the Biomedical Sciences.
Sotelo holds three degrees from Pontificia Universidad Católica de Chile: a bachelor's degree in biochemistry, with distinction (2015), a master's degree in neurochemistry (2017) and a doctorate in cellular and molecular biology, with distinction (2020). Also in 2020, he received a doctorate in sensory physiology and animal. Behavior from the University of Bristol, Bristol, UK.
Resource:
EYES ABSENT and TIMELESS Integrate Photoperiodic and Temperature Cues to Regulate Seasonal Physiology in Drosophila, published June 15, 2020, Proceedings of the National Academy of Sciences (PNAS), lead author Antoine Abrieux and co-authors Joanna Chiu, Yao Cai, and Yongbo Xue.
- Author: Kathy Keatley Garvey
Fettig's seminar also will be virtual. The Zoom link:
https://ucdavis.zoom.us/j/95882849672
UC Davis doctoral student Crystal Homicz will host him.
"Bark beetles are a major disturbance in western forests," Fettig says in his abstract. "Several recent outbreaks of species such as mountain pine beetle, spruce beetle, and western pine beetle are among the most severe in recorded history. There is strong evidence that climate change has increased the impacts of bark beetles. For example, in California warming and exceptional drought resulted in mortality of more than a 100 million trees from 2014-2017. Much of this mortality was attributed to western pine beetle colonizing drought-stressed hosts. I will discuss observed and projected changes in climate, the direct and indirect effects of climate change on bark beetles and forests, and management actions that increase the resilience of forests to bark beetles and climate change."
Fettig advises Homicz, who began her studies with forest entomologist and chemical ecologist Steve Seybold (1959-2019). Her dissertation research focuses on western pine beetle and red turpentine beetle interactions with forest disturbances, such as drought, wildfire and prescribed fire.
Fettig received his bachelor's degree (1993) and a master's degree (1996) from Virginia Tech University, and his doctorate in forest entomology in 1999 from the University of Georgia.
Of his current research, he writes on the USDA website: "My personal research program has three major emphases: (1) determination of short and long-term implications to forest health of prescribed fire and/or mechanical fuel treatments (silvicultural thinning) used in the large-scale restoration of fire-adapted forest ecosystems, (2) development of chemical, silvicultural and semiochemical-based monitoring and management tactics for Dendroctonus and Ips bark beetles, and (3) determination of the role of semiochemicals in the behavior of bark beetle species of economic importance."
Fettig's most recent publication, "Fire and Insect Interactions in North American Forests," co-authored by Homicz and several other colleagues, appears in a 2022 edition of Current Forestry Reports. Abstract: "Fire has both positive and negative effects on insects. Bark beetle and defoliator epidemics have positive and negative effects on wildfires. Additional study of these relationships is warranted given the effects of climate change on forests and forest disturbances, recent declines in some pollinator species in North America, and interests in restoring fire-adapted forest ecosystems."
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. They are coordinated by urban landscape entomologist Emily Meineke, assistant professor. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.
