resin canals analogous/homologous to secretory canals??

[Mike Crisp]

Jorge Santiago-Blay wrote:

>A querry: Are resin canals found in some gymnosperm genera analogous and/or
>homologous to the secretory canals/cells present in some angiosperms?

The apparently natural group of angiosperm families consisting of
Pittosporaceae, Apiaceae and Araliaceae all have schizogenous ducts in the
pericycle producing mucilage, resin and ethereal oils - see for instance:
Van Tieghem, P. (1872). Les canaux secreteurs des plantes. Annales des
Sciences Naturelles Series 5 16, 140-201.
Van Tieghem, P. (1884). Sur les canaux secreteurs du pericycle dans la tige
et la feuille des Pittosporees. Bulletin de la Societe Botanique de France
Series 2 31, 43-44.
Judd, W. S., Sanders, R. W., and Donoghue, M. J. (1994). Angiosperm family
pairs: preliminary phylogenetic analyses. Harvard Papers in Botany 5, 1-51.

Offhand I have forgotten which other angiosperm groups have such
structures, but it appears that in the above group at least, they are a
derived feature and probably not inherited from (i.e. homologous with)
resin canals in conifers and the like.



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Dr. Michael D. Crisp
Senior Lecturer in Plant Systematics
Division of Botany & Zoology
Australian National University       Phone int+ 61 6 249 2882
Canberra, ACT 0200, Australia         Fax int+ 61 6 249 5573

  WWW http://online.anu.edu.au/BoZo/profiles.html
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