Gibberelin inhibitors

[Tony Travis]

Thomas Bjorkman (Thomas_Bjorkman at edu.cornell) wrote:
: In article <1993Feb15.113349.13686 at gserv1.dl.ac.uk> Tony Travis,
: ajt at rri.sari.ac.uk writes:
: >Is the plant responding to a mechanical stimulus here, or is it eg.
: >temperature (from the hands) or damage to the hairs on the surface and
: >consequent changes is the thickness of the boundary layer ?
: >
: >Or, is it perhaps a chemical transferred from your green fingers ? ;-)
: 
: It is the mechanical stimulus.  The most familiar example is probably the
: curling of pea tendrils when they contact a support.  However, stems are

What is the nature of the plant's sensitivity to the mechanical stimulus?

Presumably growth on the contact side of the stem/tendril is inhibited?

: also quite sensitive.  Mark Jaffe and Cary Mitchell have been working
: quietly on this for decades.  A few years ago Janet Braam was identifying
: genes turned on (in Arabidopsis) by spraying various compounds on the
: plants. .She found the same genes turning on regardless waht she
: sprayed--even water.  It turned out to be the same mechanical stimulus. 
: Both the growth response and the mRNA accumulation are fast--a few
: minutes.

I remember the work on calmodulin you mentioned from a previous
discussion on bionet.plants about responses to mechanical stimuli. My
interest in this topic concerns the differences between weak-strawed
and stiff-strawed crop varieties in relation to yield, nutritional
value and susceptibility to lodging.

Do you think is would be a practical proposition to select varieties
that are able to _adapt_ to mechanical stress?  If so, the partitioning
of assimilates into vascular tissue that I believe is an important
factor in reducing the yield of stiff-strawed varieties could be
avoided without the risk of losing the entire crop because of lodging
as often occurs in higher yielding weak-strawed varieties.

	Tony.




-- 
Dr. A.J.Travis,                       |  JANET: <ajt at uk.ac.sari.rri>
Rowett Research Institute,            |  other: <ajt at rri.sari.ac.uk>
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