Cookies Policy

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here


No metrics data to plot.
The attempt to load metrics for this article has failed.
The attempt to plot a graph for these metrics has failed.
The full text of this article is not currently available.

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Access this article

+ Tax (if applicable)
Add to Favorites
You must be logged in to use this functionality

image of IAWA Journal

The anatomy of the primary tissues and secondary phloem in the stem of Delarbrea paradoxa Vieill. (Araliaceae) was examined with emphasis on structure and topography of secretory canals. Secretory canal systems of primary (axial canals in cortex and pith, radial canals in medullary rays) and secondary origin (axial canals in secondary phloem, radial canals in rays of secondary phloem and secondary xylem) were distinguished. Two distinct types of axial parenchyma (sheath parenchyma near axial secretory canals, and phloem parenchyma associated with conducting elements) occur in the secondary phloem. Distribution, size and number of cells per strand, occurrence of starch, and mode of transformation during phloem collapse serve to distinguish these two types. Three stages of secretory canal development (canal formation, active secretion, and senescence) were distinguished on the basis of TEM observations. The secretory canal lumina are formed simultaneously with the differentiation of meristematic cells into epithelial secretory cells. During the active secretion phase the epithelial cells contain leucoplasts aggregated into small groups, each accompanied by 2 to 3 mitochondria. These aggregations indicate terpene production in the cell. The secretion of terpenes is accompanied by swelling and loosening of the cell walls facing the canal lumina. Secretory processes were not indicated in the highly vacuolated senescent epithelial cells.


Full text loading...


Data & Media loading...

Article metrics loading...



Can't access your account?
  • Tools

  • Add to Favorites
  • Printable version
  • Email this page
  • Subscribe to ToC alert
  • Get permissions
  • Recommend to your library

    You must fill out fields marked with: *

    Librarian details
    Your details
    Why are you recommending this title?
    Select reason:
    IAWA Journal — Recommend this title to your library
  • Export citations
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation