INSECTS - Candidate genes and expression profiling in tree-insect interactions

Start date: 2007

Activity: JERA 3.2

Responsible partners: P1, P28, P8, P12, P23, P25

Contact persons:

Documents:   Project Description

Objectives:

Interactions between trees and their symbionts and/or pathogens/parasites are a driving factor for developmental and therefore also for evolutionary processes in forest ecosystems. Genetic analyses of both system partners give insight into such processes. Here, we concentrate on interactions between trees and insect species, and with our studies we want to raise the following questions:

(1) Why do some trees suffer less from defoliation than others?
(2) Are these trees genetically different from more sensitive ones?
(3) Does genetic diversity of the insects correlate with tree infection level?

Observations in European forests revealed that in years with high insect population densities not every oak tree is defoliated in the same extent. In May oaks can be detected growing side by side of which one is totally defoliated (defined as “sensitive”) and the other not (defined as “tolerant”). Our interpretation of this observation is that generally oaks are sensitive against insect grub, but single trees show a more or less extended sensitivity or tolerance.
The major question in this network proposal is why do some trees show lower levels of defoliation following insect attacks? A possible explanation is that these trees reveal a “defence response mechanism” against insect grub.