PARENT SESSION
Poster Session # 15: Plant Ecology.

Wednesday, August 6 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.

Genome-wide effects of elevated CO₂ in the loblolly pine FACE experiment.

Moura, Catarina^*,1, McElrone, Andrew¹, Watkinson, Jonathan², Grene, Ruth², Jackson, Robert¹, ¹ Duke University, Durham, NC² Virginia Tech, Blacksburg, VA

ABSTRACT- Rising atmospheric CO₂ concentrations are altering the present environment and creating new challenges for forest tree species. Physiological and structural responses to environmental change are controlled by molecular processes including changes in the expression of a large number of genes. Studies to date generally involve a non-woody plant (Arabidopsis), greenhouse conditions and/or a limited number of genes. There is a special need to understand global cellular responses in more complex organisms and to clarify the role of certain genes in their natural context. This study provides a larger, genome-wide view of the responses of an important and field-grown woody species, loblolly pine (Pinus taeda), to changes in atmospheric CO₂ concentration. We compared the patterns of gene expression in needles of loblolly pine exposed to Ambient and Elevated (Ambient + 200ppm) CO₂ levels in the Duke Forest FACE experimental site. For this purpose we used microarray slides each containing ∼2000 loblolly pine ESTs (expressed sequence tags). Among the ESTs there are some coding for enzymes involved in photosynthesis and nitrogen metabolism, two processes important for the response and potential acclimation of loblolly pine to elevated CO₂. Understanding the molecular mechanisms underlying physiological acclimation will allow us to better predict responses of forests under future climatic scenarios.

Key words: Microarrays, Pinus taeda, Elevated CO₂, Gene expression