135. Mizuta, S., Kurogi, U., Okuda, K.,
and R. M. Brown, Jr. 1989. Microfibrillar structure, cortical
microtubule arrangement and the effect of amiprophos -methyl on
microfibril orientation in the thallus cells of the filamentous
green alga, Chamaedoris orientalis. Annals of
Botany 64: 383-394.
Microfibrillar structure, cortical microtubule
orientation and the effect of amiprophos-methyl (APM) on the arrangement
of the most recently deposited cellulose microfibrils were investigated
in the marine filamentous green alga, Chamaedoris orientalis.
The thallus cells of Chamaedoris showed typical tip growth.
The orientation of microfibrils in the thick cell wall showed
orderly change in longitudinal, transverse and oblique directions
in a polar dependent manner. Microtubules run parallel to the
longitudinally arranged microfibrils in the innermost layer of
the wall but they are never parallel to either transverse or obliquely
arranged microfibrils. The ordered change in microfibril orientation
is altered by the disruption of the microtubules with APM. The
walls, deposited in the absence of the microtubules, showed typical
helicoidal pattern. However, the original crossed polylamellate
pattern was restored by the removal of APM. This suggests that
cortical microtubules in this alga do not control the direction
of microfibril orientation but control the ordered change of microfibril