On Tue, 01 May 2007 15:19:04 -0700, William Rose wrote:
good deduction on my location, 80 miles north of San Francisco in the
Redwoods, a temperate rain forest.

First set of foothills east side of the Willamette valley here. Similar but
non-equivalent climates. Redwoods do ok here, but they don't flourish. But
I probably can match you banana slug for banana slug. g Flax can be
weedy around here. But not in the shade of doug firs.

So here's the deal. I'm trying to grow flax for its' omega-3 fatty
acids. I bought flax seed marked omega because I thought that implied a
higher level of the omega-3s in the seeds
http://www.horizonherbs.com/group.asp?grp=45&pgNUM=4. Maybe it does but
the two varieties are both identified as Linum usitatissimum. Got any
idea how different a cultivar could be from its' genome in expressing
it's genetic traits?

Can I recast your question for you? I don't think you're asking what you
think you're asking.

What I think you're asking is basically, can cultivar A be quite different
from "generic species", and can cultivar A be quite different in some property
than cultivar B?Â*The answer to both of those questions is "yes". Consider,
for instance, wild common sunflower, Helianthus annuus. Smallish heads
on lanky plants with medium sized leaves. But from the wild plants were
selected a couple of types under heavy agronomic cultivation now: oil-seed
sunflowers generally look much like their wild prototypes -- multiple heads,
often kinda rangy looking plants, small seeds, but a lot more oil per seed and
per plant than the wild types. The other agronomic form is the
large-seeded form grown for confectionary use... the packaged snack sunflower
seeds. Seeds are relatively large, relatively low in oil, and heads are
much larger (and usually just one per plant) compared to the wild or oil
seed types. And then there are the decorative forms that have suddenly
become popular in horticultural circles, like the pink flowered sunflowers
or the "teddy bear" type cultivars.

You'll see exactly the same thing looking at most multi-purpose crops.
In flax, there are cultivars of Linum usitatissimum that make lovely,
strong bast fibers... they're the ones that are cultivated to make linen
from. Nobody really cares about the seed oil content of these, so chances
are it's around that of the wild type flaxes. Then there are the oil seed
types bred for linseed oil 50 or more years ago; high oil content, but I'd
expect the amount of linolenic acid (the major omega 3 fatty acid in flaxseed)
to be somewhat variable, because the breeders then were looking for gallons
of linseed oil per acre, and the presscake shouldn't actually kill animals
it was fed to g. The new push for high amounts of omega-3 fatty acids
probably caused breeders to go back and check the oil seed cultivars available,
and either market one with decent amounts of linoleic acid production as
"health food" or perhaps to breed especially for linolenic acid content.
I wouldn't expect oil seed flaxes to have nice strong fibers for making linen
fabric. Different cultivars, different genetic backgrounds, different
tissues and composition of plants.


My guess is that the "omega" seed they're offering is an oilseed type,
and may be selected for high linolenic acid. And the "brown flax seed"
they're offering at a lower cost is whatever they can get or produce cheap.
BUT, without an analysis, I'd be unwilling to state that their "omega" is
higher than their "brown flax seed" in linolenic acid content. They don't
actually state that their seed is the cultivar called 'Omega' in this
research report, and the form of the name they use is not what I'd expect
from an operation with plant breeders, but it may be the same. Or maybe
not. Anyhow, here's the research report mentioning 'Omega':
http://ag.montana.edu/warc/flax.htm -- it appears that there is a high
linolenic acid cultivar, with lighter-colored seed, called 'Omega'

Where would you go to find information on what cultivars are particularly
high in linolenic acid? You could try a google search with something like
[linolenic flax content seed], but I'd probably go to a couple of
other abstracting services -- PubMed for medically related data, and
Agricola for plant breeding, etc. and poke around for names of cultivars
and comparative data tables. I'd expect Agricola to be the richer source.
Pubmed is he http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed
and Agricola is he http://agricola.nal.usda.gov/ (I'd search articles,
not books, first)

Once I got the names of some cultivars with the desired properties, I'd
try to find seed and see which grew well for me and which I could stand to
eat. g

More thoughts possibly irrelevant to your immediate question:
1) dark brown seeds tend to contain more flavonoids than light brown seeds.
We are all now being urged to get more dietary flavonoids for their
various antioxidant functions -- e.g., lutein, quercitin.
If you're hoping to do that at the same time, you probably want to pick
a darker seeded cultivar than 'Omega'. On the flip side, flavonoids are
pretty yucky tasting to most people, and do a wonderful job of binding
proteins. So ya pays your money and ya takes your chances on some of this
stuff.

2) Your actual question was "Got any
idea how different a cultivar could be from its' genome in
expressing it's genetic traits?" translates to me as a question that
I'd re-translate to English as "Can growing conditions make a plant do
something that's not within its genes?" And that gets to be a really
complex question that's still got a lot of research ahead of it. But right
now, the basic answer is "No." Phenotype, the plant characters we
can see, touch, taste, measure, etc. is the product of both the environment
and the genes within the individual. Genes sort of set the limits of what's
possible for the phenotype, but within those limits, environment plays
a big role in what we "see". For instance, if you grow a cherry tomato
plant in the best possible environment for producing tomatoes, with plenty
of light, the perfect temperatures, the perfect soil, the perfect amount
of soil nutrients, the perfect pH -- well, you're still going to be picking
cherry tomatoes off that plant. They might be a little bigger than
average, but they're not going to be two pounders like you might pick off
a 'Beefsteak' under the same conditions. Take that 'Beefsteak' seed and
plant it in poor conditions for tomato, and the tomatoes you get are unlikely
to be a couple of pounds each. In fact, under some really stressful
conditions, you might be picking what you think are cherry tomatoes.
But they're really 'Beefsteak', just really poorly grown 'Beefsteak'.
That's an example of environmental factors acting in concert with the
genome of an individual cultivar to produce plants that "look" different,
but are genetically the same. So another "gotcha" in your growing your
own high linolenic acid flax is that it may not produce as much linolenic
acid under your growing conditions as it does in a test plot in Montana.
Or North Dakota. Or where ever. Or it may produce more. Without an
analysis, you'll never really know.

And with that, I'll bid you good night... I've had a few too many short
nights and long days recently, and the quilts are calling to me... ;-)

Kay