In article <2gcuof$a3p at mserv1.dl.ac.uk> Dan Szymanski,
Dan_Szymanski at qms1.life.uiuc.edu writes:
> Also, there is a purple pigmentation at the base of a
>inflorescences that demonstrate a typical response, but all plants
>lack the pigmentation do not alter their growth aspect in reponse
>mechanical stimulation? Is this indicative of a requirement for
I've never seen this in tomato plants, though lack of fertilizer
makes them turn purple and slows growth.
I wish there wre good answers to your other qustions. There are a
variety of responses that are mechanical, biochemical and electrical
but I would be loath to try to put them in a causal sequence.