Figure 4.

Tissue-specific and dose-dependent changes in monoterpene and diterpene accumulation in wood and bark after treatment of trees with MeJA. A, Monoterpenoids, wood. B, Diterpenoids, wood. C, Monoterpenoids, bark. D, Diterpenoids, bark. Each concentration was tested on four trees. Analysis was performed in duplicate and results are presented as the mean with se. Wood denotes the entire xylem tissue of a stem section. Bark denotes all tissues outside the vascular cambium, including phloem, cortex, and periderm. Lower concentrations of MeJA of 100 to 500 μM induced chemical changes of wood resin terpenoids similar to those induced with 10 mm MeJA when Tween 20 was added at 0.1% (v/v) to the surface spray.