Rachel Vannette, Hellman Fellow

Vannette, who researches pollinator microbiomes, titled her innovative project  “Characterizing the Structure and Function of Pollinator Microbiomes."  She investigates  the communities of bacteria and fungi in flowers and pollinators, including bees and hummingbirds. “Our work to date suggests that microbes in flowers are common and influence pollinator behavior,” she says.

The Hellman funding will allow her to link microbial communities in flowers with their influence on pollinators by examining microbial modification of nectar and pollen chemistry, and examine how microbial effects vary among plant and pollinator species, and with environmental variation.

We remember the groundbreaking research published by Vannette and her colleagues last year in the New Phytologist journal. Their paper, titled  “Nectar-inhabiting Microorganisms Influence Nectar Volatile Composition and Attractiveness to a Generalist Pollinator,” showed that nectar-living microbes release scents or volatile compounds that can influence a pollinator's foraging preference.

Nectar-inhabiting species of bacteria and fungi “can influence pollinator preference through differential volatile production,' Vannette related last September.  “This extends our understanding of how microbial species can differentially influence plant phenotype and species interactions through a previously overlooked mechanism. It's a novel mechanism by which the presence and species composition of the microbiome can influence pollination. Broadly, our results imply that the microbiome can contribute to plant volatile phenotype. This has implications for many plant-insect interactions.”

The 11 Hellman Fellows will receive a total of $244,000 in grants for research in a wide range of disciplines. Since 2008, UC Davis has received nearly $3 million in Hellman grants, awarded to 136 early-career faculty members. The Hellman Fund provides grant monies to early career faculty on all 10 UC campuses, as well as to four private institutions.

Vannette joined the UC Davis Department of Entomology and Nematology in 2015 after serving as a postdoctoral fellow at Stanford University's biology department, where she was a Gordon and Betty Moore Foundation Postdoctoral Fellow from 2011 to 2015 and examined the role of nectar chemistry in community assembly of yeasts and plant-pollinator interactions.

She received her bachelor of science degree, summa cum laude, in 2006 from Calvin College, Grand Rapids, Mich., and her doctorate from the University of Michigan's Department of Ecology and Evolutionary Biology, Ann Arbor, in 2011. Her thesis: “Whose Phenotype Is It Anyway? The Complex Role of Species Interactions and Resource Availability in Determining the Expression of Plant Defense Phenotype and Community Consequences.”

We look forward to hearing more about this exciting research!