5: When and how much does the immune response matter?

On-Demand

Presenting Author(s)

Angela M. Smilanich

University of Nevada
Reno, Nevada

Co-Author(s)

DB

Deane Bowers

University of Colorado
Boulder, Colorado
Nadya D. Muchoney

University of Nevada
Reno, Nevada
HS

Heather Slinn

University of Guelph
Guelph, Ontario, Canada
LD

Lee Dyer

University of Nevada
Reno, Nevada
Adrian L. Carper

University of Colorado
Boulder, Colorado
JR

Justine Resnik

The insect immune response has been shown to be effective at protecting insects against internal enemies. However, the generality of this effectiveness is difficult to ascertain given the many variables that influence the strength of the immune system. The research presented here focuses on the immune system in caterpillars, and the role that it plays in defending caterpillars from natural enemies. We were also interested in how plant traits alter immunity, changing its effectiveness. Using a variety of study systems with caterpillars, we determined that 1) the effectiveness of the immune system is dependent upon the host plant consumed and, 2) sequestration of secondary metabolites suppress the caterpillar immune response, and 3) even though plant chemistry suppresses the caterpillar immune response, it leads to greater protection against viral infection by lowering virus loads. These results show that while the immune response in an important defense, insects must rely on an arsenal of defenses against the great diversity of natural enemies.