Jill Spragg*

Jill has been exploring the relationship between host genotypic variation in disease susceptibility and protection against a fungal pathogen conferred by bacterial symbionts.  She has been focussing on the interaction between pea aphids, beneficial bacteria that protect them against pathogens, and aphid-specific fungal pathogens.  We predict that at least some aphid clones will be less susceptible to fungal infection when carrying the symbiont Regiella insecticola, but the difference in resistance conferred between host genotypes should reflect the complexity of symbiont-host interactions.  We are interested to see whether differences in resistance are due to intrinsic susceptibilities in particular aphid clones, the strain of symbiont the aphid carries, or some interaction between particular hosts and symbionts. Jill has also been examining the expression of antimicrobial peptides in pea aphids in response to fungal infection.

* Jill is now working in Tom Little’s lab in Edinburgh before she heads to the University of Washington to do her PhD.

Dan Sok

Despite his smiley appearance, Dan is preoccupied with stress; not human stress, mind you, but aphid stress. He has been studying how exposure to the aphid alarm pheromone EBF alters aphids’ reproductive investment and resistance to diseases. Aphids exposed to stressful conditions can produce winged dispersing offspring. Dan is examining whether these winged offspring are also loaded with secondary symbionts to provision them in their new environment.

Ben Parker

Ben and I have been working on a project to assess the costs of immunity in pea aphids. Developing, maintaining and using an immune system is takes lots of resources that could go into other important things like reproduction or growth. So immunity must be traded off against other traits. We’re looking at whether we can detect costs in aphid fitness when aphids are given a variety of different pathogens.