- Author: Kathy Keatley Garvey
Congratulations to UC Davis entomology professor Diane Ullman who has just a received Fulbright to research plant virus-insect interactions in France. She will be studying plant viruses and the insects that transmit them.
Her sabbatical, to begin in November, will take her to Montpellier, France, to work with renowned vector biologists Stéphane Blanc and Marilyne Uzest at the National Institute of Agronomic Research (INRA) on the Campus International de Baillarguet near Montpellier. The Biologie et Génetique des Interactions Plante-Parasite (UMR-BGPI, CIRAD-INRA-SupAgro) focuses on plant pathogens and their interactions with arthropod vector in agroecosystems.
She will be studying plant viruses in the genus Orthotospovirus (family Tospoviridae). This family holds the only plant infecting members in the order Bunyaviriales. The other viruses in this order infect animals and humans and are transmitted primarily by mosquitoes and ticks.
Ullman, an international authority on orthotospoviruses, said that "new evidence suggests the bunyavirus, Rift valley fever virus (an animal infecting member of the Bunyavirales), uses a multicomponent system in which individual virions do not co-package all segments and infection requires virion populations, a possibility with profound implications for virus evolution and antiviral target discovery...I will test the hypothesis that orthotospoviruses use multicomponent genome organization and segment copy regulation occurs in their hosts.”
The UC Davis professor has researched insect-transmitted plant pathogens for 37 years, targeting numerous insect vector species--from thrips, whiteflies, and leafhoppers to mealybugs--and the plant pathogens they transmit, including viruses, phytoplasma and bacteria.
“Sustainable management of insect-transmitted pathogens is a key concern for food production in France and the United States,” Ullman wrote in her Fulbright application. “Both countries grow many of the same crops and growers face similar challenges from insect-transmitted plant viruses. Current management strategies rely heavily on pesticides that may cause significant health and environmental concerns, including damage to bees and other pollinators, as shown with neonicotinoid pesticides. Clearly, better knowledge about these insect-transmitted viral systems…has potential to reduce pesticide use by providing novel and innovative technologies to manage tospoviruses and thrips in France and the United States.”
Ullman, former chair of the Department of Entomology and Nematology and a former associate dean with the UC Davis College of Agricultural and Environmental Sciences, expects the project will build strong research relationships between UC Davis and Montpellier that will lead to grant applications for international research and scholarly exchange opportunities for scientists, students and post-doctoral scholars.
- Author: Kathy Keatley Garvey
There should be a crowd at the UC Davis Department of Entomology seminar on Wednesday, Dec. 7.
That's when evolutionary ecologist Ruth Hufbauer, associate professor at Colorado State University, Fort Collins, who researches insect-plant interactions, will speak on “The Roles of Demography and Genetics in the Founding of New Populations.” Her talk is set for 12:10 to 1 p.m. in 122 Briggs Hall. Plans call for it to be recorded and broadcast at a later date on UCTV.
This is the last in the series of UC Davis Department of Entomology seminars for the fall quarter. Host Louie Yang, assistant professor of entomology, will introduce Hufbauer.
Have you ever wondered how insect populations become established in a new environment? Their fate rests on both their demographic and genetic compositions, Hufbaue says.
Hufbauer, who co-organized a seminar on "Evolution and Biological Control" at the Entomological Society of America's 59th annual meeting, held last month at the Reno-Sparks Convention Center, says that "Establishment success increases with the number of founders as well as with their genetic diversity. However, because more individuals typically harbor more genetic variation, demography and genetics are linked. To disentangle them requires factorial experiments manipulating numbers of founders of different genetic backgrounds--inbred to outbred.”
Hufbauer will present data from two such factorial experiments. “In both systems, demography and genetic background interact to determine the success of founders. Inbreeding led to reduced success, and those effects depended upon the species and the environment. Inbreeding and genetic drift can, however, have positive effects as well, particularly in the case of purging of deleterious mutations. A third data set supports the idea that purging can happen in natural populations, and may influence subsequent population dynamics.”
Hufbauer, who grew up in California, earned her bachelor of arts degree at UC Berkeley and her doctorate at Cornell. In 2000, she joined the faculty of the Department of Bioagricultural Sciences and Pest Management, Colorado State University.
On her website, Hufbauer quotes Ukrainian geneticist/evolutionary biologist Theodosius Dobzhansky (1900-1975): “Nothing in biology makes sense except in the light of evolution.”
She acknowledges that “these days studying and teaching evolution in the U.S. is quite controversial." So, she's thoughtfully posted some links to "sites from the scientific community aimed to educate people about the basics, not only of evolutionary biology, but also what physics and chemistry teach us about the world.”