Are there "Identical Twin" plants?
CEREOID at prodigy.net
Sat Dec 16 18:08:13 EST 2000
Okay George, you've led us on long enough and you are starting to come
across as a troll.
Its time for the bottom line.
What is your point?
"George Hammond" <ghammond at mediaone.net> wrote in message
news:3A3BE786.5235C70 at mediaone.net...
> Wayne Parrott wrote:
> > George Hammond wrote:
> > > GH: You've totally missed the point. I DON'T WANT TO CONTROL
> > > What I want to know is, what is the Standard Deviation of plant
> > > growth in the "real environment" when we are talking strictly
> > > a crop of geneetically identical plants?
> > > Now, somebody in agriculture must KNOW the answer to this, say
> > > for potatoes, or onions or some other asexual crop plant.
> > It depends on the variety and on the trait, and it depends if you are
> > about the SD within a field or between fields. For something like
> > the SD would be close to zero.
> GH: Right, I understand that.
> > For something like height or yield, it would
> > fairly uniform within a field (barring spots which are overly wet/dry,
> > otherwise inappropropriate),
> GH: YES, this is what I'm talking about, "gross overall size",
> I'm NOT concerned with "specific traits".
> There is such a thing as a "growth curve" for
> ALL plants and animals and the "plateau" of this
> curve represents what we call "maturity", or
> "terminal growth".
> However, there is reason to believe that there is such
> a thing as a "theoretical growth curve" for any given
> genetic species, and that in fact, since a large cloned
> plant population has a "terminal growth variance"; that very
> few plants EVER achieve this "theoretical growth curve".
> Would you agree with this speculation?
> but could be quite large between fields, depending
> > on how distant they are. Breeders generally call this genotype x
> > interactions. Genotypes are known which are more stable across
> > others. In the end, the SD is difficult to predict without measuring
> GH: Yes, it is the "between fields" SD that I am talking about.
> You apparently agree that such a thing exists and can be
> > Keep in mind that plants need not reproduce vegetatively to be
> > identical. Hybrids from inbred parents (as in a field of corn) are
> > identical. So are inbred plants (as in a field of soybean) and
> > (as in dandelions).
> GH: yes, this is most interesting. One researcher pointed
> out that laboratory mice have been purposely inbred for
> thousands of generations, so that within a strain, they
> are virtually genetically identical.
> My question would immediately be "how much of a growth curve
> variance" could these genetically identical mice manifest.
> You see; the question here is nothing but the old NATURE-NURTURE
> discussion.... with a NEW TWIST.
> It is now hypothesized that higher animals, and probably plants,
> have something which we could call a "nominal maximum genetic
> size", and that in the natural environment, very few IF ANY
> individual specimens EVER ACHIEVE IT.
> The object then, becomes the task of PROVING THIS CONJECTURE.
> > Because of the variability that a given variety of genetically identical
> > exists, seed companies generally avoid having a central breeding
> > Instead, they depend on having multiple breeding stations, each one
> > the immediate vecinity.
> GH: I see. BTW, on the question of "nominal maximum genetic
> size", I think it should be mentioned that "giant vegetables"
> are a NATURE (genetic) effect and not a NATURE (environmental)
> effect. Seeds for "giant vegetables" have an altered "cell
> division gene" that makes the cell-division much more rapid
> and that accounts for their giant size.
> This is further evidence, that for any GIVEN GENETIC SPECIES
> there is such a thing as a "maximum genetic size" of
> the adult.
> BE SURE TO VISIT MY WEBSITE, BELOW:
> George Hammond, M.S. Physics
> Email: ghammond at mediaone.net
> Website: http://people.ne.mediaone.net/ghammond/index.html
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