The Impact of Genomics on Advances in Herbivore Defense and Secondary Metabolism in Populus

Part of the Plant Genetics and Genomics: Crops and Models book series (PGG, volume 8)


The genus Populus is ideally suited for applying the tools of genomics to plant-herbivore interactions and secondary metabolism. Populus is rich in phenolic secondary metabolites including condensed tannins and salicylate-based glycosides; these and related-compounds strongly shape the interactions of Populus with a host of invertebrate and vertebrate herbivores in diverse natural environments and commercial plantations. Microarray studies have been instrumental in delineating the induced defense response to herbivore damage and in identifying defense-related genes in Populus. These can now be functionally tested in vitro as recombinant proteins as well as in vivo in transgenic plants. Analysis of the P. trichocarpa genome has provided access to candidate genes likely to be important for the synthesis of phenolic secondary metabolites, thereby accelerating progress in understanding the ecological functions of these compounds. Combining genomics with improved metabolite profiling will lead to a deeper understanding of how the substantial variation in phenolics among Populus species and genotypes is generated, as well as the ecological consequences of this variation.


Secondary Metabolism Condensed Tannin Phenolic Glycoside Flavonoid Pathway Populus Species 



We thank our many students and research collaborators, whose work made possible the advances reported here. We also thank Ken Keefover-Ring for creating Fig. 1. R. Lindroth’s research has been supported by funding from the U.S. Department of Agriculture (National Research Initiative), U.S. Department of Energy (Office of Biological and Environmental Research), and the National Science Foundation (particularly, grants DEB-0074427, DEB-0344019 and DEB-0425908). P. Constabel acknowledges the generous support of the Natural Sciences and Engineering Research Council of Canada (NSERC) in the form of Discovery, Genomics, and Strategic Grants.


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© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  1. 1.Department of BiologyCentre for Forest Biology, University of VictoriaVictoriaCanada
  2. 2.Department of EntomologyUniversity of WisconsinMadisonUSA

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