© 2005 Heron Publishing—Victoria, Canada
Changes in anatomy and terpene chemistry in roots of Douglas-fir seedlings following treatment with methyl jasmonate
Dezene P. W. Huber (1), Ryan N. Philippe (1), Lufiani L. Madilao (1), Rona N. Sturrock (2) and Jörg Bohlmann (1, 3)
1. Michael Smith Laboratories and Departments of Botany and Forest Sciences, University of British Columbia, 237 – 6174 University
Blvd., Vancouver, BC V6T 1Z4, Canada / 2. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, 506 West Burnside Road, Victoria, BC V8Z 1M5,
Canada / 3. Corresponding author (bohlmann@interchange.ubc.ca) / Received June 2, 2004; accepted October 15, 2004; published online June 1, 2005
Summary
Replicated trials were conducted on two full-sibling families of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings. In response to the application of a 0.01% solution of methyl jasmonate (MeJA) to the soil of potted
seedlings, numerous anatomical and chemical changes were observed in the roots, stem and foliage. These changes were, for
the most part, similar for both sib groups. Methyl jasmonate induced traumatic resin duct formation in roots and stems. Chemical
differences between MeJA-treated and control seedlings were mainly limited to the roots and stem, though some changes also
occurred in the foliage. A total of 35 terpenoids were observed in the P. menziesii seedlings. In response to MeJA treatment, several of the 22 detected monoterpenoids (linalool, bornyl acetate, camphene,
myrcene, α- and β-pinene, tricyclene and β-phellandrene) increased significantly in roots and stems, whereas (E)-β-ocimene decreased significantly in the foliage. Four of the five detected sesquiterpenoids (α-humulene, germacrene D,
longifolene and (E)-caryophyllene) increased significantly following MeJA application, mainly in the root and stem. Four of the eight detected
diterpenoids (abietate, levopimarate, palustrate and sandaracopimarate) increased in response to MeJA treatment, but only
in root and stem tissue. This study provides the first description of the effects of MeJA applied to roots through the soil
on the anatomy and terpene chemistry of a gymnosperm. This comprehensive inventory of terpenoids in P. menziesii, with and without MeJA treatment, may facilitate identification of terpenoid-related resistance traits. Potential practical
applications of MeJA treatment of conifer roots as a pest management strategy are discussed.
Keywords:
forest pathology, forest pest management, induced conifer defense, octadecanoid, oleoresin, Pseudotsuga menziesii, traumatic resin duct, tree biotechnology.
