Plant defenses and climate change: doom or destiny for the lodgepole pine?

Authors: LEWIS, KATHY - University Of North British Columbia; Wallis, Christopher

Submitted to: Trade Journal Publication
Publication Type: Trade Journal
Publication Acceptance Date: 5/30/2012
Publication Date: 7/1/2012
Citation: Lewis, K.J., Wallis, C.M. 2012. Plant defenses and climate change: doom or destiny for the lodgepole pine? Trade Journal Publication. 19(4):10-11.

Interpretive Summary: Lodgepole pines, an important timber species in British Columbia, are facing reduced growth potentials due to climate-change associated insect and disease outbreaks. Research was undertaken to understand whether or not assisted migration, that is replanting pine provenances from hotter climates to cooler sites, will lead to more resilient plantations. Pines from southern, warmer, and wetter locations may possess greater capacity to tolerate insects and pathogens. This research observed that pines from wetter, warmer biogeoclimatic zones exhibited not only reduced foliar disease severity, but also possessed greater foliar levels of phenolic and terpenoid compounds, both of which were previously shown to be associated with host defense against pathogens. Therefore, assisted migration of lodgepole pines appears a tenable strategy to reduce some negative impacts of climate change in British Columbia.

Technical Abstract: Lodgepole pine is a species of great importance to the forestry industry of British Columbia. However, recent climate-change associated outbreaks of insect pests (i.e. the mountain pine beetle) and diseases (Dothistroma needle blight) have limited productivity of stands throughout its northern range. One solution is to re-plant pine plantations with seedlings from southern, warmer, and wetter origins as these might be more tolerant of insects and disease damage. This research observed that provenances from southern, warmer locales had reduced disease severities as well as increased constitutive foliar levels of secondary metabolites (phenolics and terpenoids). Since both phenolics and terpenoids are associated with host defense against pathogens, it appeared that increased levels of these compounds resulted in increased tolerance to foliar disease in lodgepole pine. Thus, the planting of lodgepole pines from southern locales to northern locations in light of climate change may ultimately reduce the impact of climate change associated disease outbreaks.