Gary Felton Seminar: How Plants Turn on Their Anti-Herbivore Defenses

How do plants defend themselves from herbivores and turn on their defenses?

Professor Gary Felton, head of the Department of Entomology, Pennsylvania State University, will speak on "Herbivore-Associated Microbes Mediate the Intersection of Herbivore and Plant Immunity" at  the UC Davis Department of Entomology and Nematology's seminar at 4:10 p.m., Wednesday, May 9 in 122 Briggs Hall. This is a Storer Endowment-sponsored seminar.

Felton, who received his doctorate in entomology at UC Davis in 1988, writes in his abstract: "The lateral transfer of microbial genes from bacteria, baculoviruses, polydnaviruses and fungi has shaped the genomes of herbivores such as Lepidoptera. Such transfer has enabled herbivore speciation and the successful colonization of host plants among other impacts on fitness. In present time, herbivore-associated microbes play an exceedingly important role in mediating phenotypic variation in herbivores. Using the example of one highly polyphagous herbivore, the tomato fruitworm (Helicoverpa zea) we will show how herbivore associate microbes strongly impact the phenotype of the herbivore and its impact on induced defenses in the host plant."

"Herbivore cues found in their saliva are recognized by plants to turn on anti-herbivore defenses," Felton says. "Microbes associated with these herbivores including bacteria, fungi, baculoviruses, and polydnaviruses impact the composition of these salivary cues and ultimately mediate the ability of the host plant to mount their anti-herbivore defenses."

Felton presented the Thomas and Nina Leigh Distinguished Alumni Seminar in May of 2011 on “Dialogues at the Plant-Herbivore Interface” to the UC Davis Department of Entomology and Nematology.

Overall, he says of his research on his website: "My research program uses molecular, proteomic and physiological approaches to investigate insect-plant interactions. My main interests are investigating the counter measures herbivores use in overcoming host plant defenses. Particular interest is on the role of herbivore salivary signals in suppressing the induced defenses of host plants. The role of saliva of blood feeding arthropods in suppressing the defenses of their vertebrate hosts has been comparatively well studied; however, very little is known about how the saliva of herbivores may interfere with plant defensive responses. Our projects focus primarily on the saliva of caterpillars. Recent findings indicate that saliva is enriched with an array of molecules that function in defense against microbial infection, digestion of plant tissues, and in suppressing induced defenses of plants. We employ a variety of surgical and genetic approaches (e.g., RNA interference) to examine function(s) of saliva."

Felton, who has served as professor and head of the Penn State Department of Entomology since 2000, received his bachelor of science degree from UC Irvine in 1975, followed by his master's degree from the University of Kentucky, Lexington, in 1983. He then enrolled in the UC Davis entomology graduate school program, studying with Sean Duffey.

After receiving his doctorate from UC Davis in 1988, he did postdoctoral work at UC Davis from 1988 to 2000, and then joined the University of Arkansas, Fayetteville, as an assistant professor in 2000. He was promoted to associate professor in 1994, and to professor in 1998. He left the University of Arkansas in 2000 to accept the professor and department chair position at Penn State.

Want to know more about the tomato fruitworm, also called the cotton bollworm and corn earworm? See the UC Statewide Integrated Pest Management website. "Management of tomato fruitworm requires careful monitoring for eggs and small larvae."

The seminars are coordinated by assistant professor Rachel Vannette; doctoral candidate Brendon Boudinot of the Phil Ward lab, and Extension apiculturist Elina Lastro Niño.