Grants and Contributions:

Grant or Award spanning more than one fiscal year. (2017-2018 to 2022-2023)

The emerald ash borer (EAB) is an invasive wood-boring beetle whose larvae tunnel under the bark of ash trees and can kill an infested tree within a few years. The EAB was introduced accidentally from Asia in the 1990s, and since its discovery in the Detroit-Windsor area in 2002, the insect has spread across Ontario and into Quebec (as well as to large parts of the USA), killing millions of ash trees in forests, parks and metropolitan areas. Ash is a key species in urban forestry, making up a significant proportion (up to 40%) of urban trees in municipalities across Canada. During ash infestation, the EAB feeds on the tree’s phloem, resulting in the progressive destruction of the vascular system of the tree. There is a pressing need to explore current tree genomics tools to better understand ash response to the EAB in order to improve its management and provide genetic markers for tree improvement.

The mechanisms of resistance to EAB attack are currently unknown; however, it is possible to investigate the biochemical processes that underlie the ash defense response in susceptible trees (ie. Green Ash). Asian species of ash show greater resistance than North American species because they have coevolved with the insect. Studies focusing on the vascular cambium of resistant vs susceptible ash trees after larval feeding have revealed an overlapping set of defense related genes that display increased gene expression in EAB resistant trees. This research program will focus on the use of an integrated systems approach to identify the genes that are activated during the defense response to EAB, in order to identify the key regulatory elements governing this induction. By identifying the main components of the molecular switch of the defense response we should be able to improve stimuli response either by genetic or physiological means for a swifter and/or stronger stress response to prevent the spread of the EAB.