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Are there "Identical Twin" plants?

George Hammond ghammond at mediaone.net
Sat Dec 16 22:15:04 EST 2000

Rich Cooper wrote:
> [snip]
> The genetic expression curve could be measured by varying a selected
> set of environmental parameters, and the effect of combinations of these
> parameters could define the growth curve you're describing.

GH:  Hey Rich.... you apparently understand what I'm talking 
     about.  But can't this be easily ascertained from existing
     data without doing any experiments?  I mean, there must
     be archives knee deep in "crop yield data" for asexual
     clonal plants (potatoes, onions and floriculture).  For
     Pete's sake we don't have to launch any new experiments do we?

> In a laboratory, very careful control of all the variables (such as
> total moisture, total light and spectrum exposure, specific chemicals)
> with a computer controlled system could mathematically characterize
> the effect you're describing.  Every instance of the genetically identical
> individual could be measured with sensors that report on these variables,
> or high accuracy mesurement dispensers for water, chemicals, etc,
> could very precisely control the variables to get the variation you
> describe versus the controlled variables.

GH:  I''m impressed by one thing.... you apparently comprehend
     what I'm talking about when I refer to a "growth curve deficit".
     it seems that no one else does.

> Next, consider two families of plants, with the members of each family
> genetically identical to each other, but different from the other family
> in genetically known ways.  The same experiment should show a
> different expression function for the two families.  The differences
> in growth curve could be attributed to the genetic differences solely.

GH:  yes... christ... you actually understand the problem!
     For instance, if you had 3 brand new cars Volkswagon,
     Mazzeratti, and plymouth; it is known that the top
     speeds under perfect conditions are 85, 165, and 100.
     Now fill all the tanks with "bad gasoline", and we
     find the top speeds to be  60, 130, and 80.  This
     indicates a "performance deficit" of 25, 35 and 20
     respectively.  The bad gasoline is a "nurture" effect,
     while the difference in the original top speeds is
     the "nature" (or genetic) effect.
       We should be able to do the same thing with plants.
     What I'm trying to demonstrate, is that there is a
     universal "bad environment" effect, whereby, NO PLANT
     ever reaches it's "genetic top speed"... it's
     "genetic full growth" as it were.


GH:  In conclusion, what we are asking, is whether there
     is a "universal growth deficit" for all plants, in
     that no plant ever reaches it's true "genetic potential
     size" because of the shortcomings of the environment.
       It seems to me that the large variance
     among "clonal plants", at least in the wild,  de facto
     proves this contention.  Even under controlled hothouse
     conditions there is a significant variance.

> Sincerely,
> Rich Cooper

George Hammond, M.S. Physics
Email:    ghammond at mediaone.net
Website:  http://people.ne.mediaone.net/ghammond/index.html

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