Aquaponics Digest - Thu 04/08/99
Message 1: Tilapia Feed
from "Robert mabry"
Message 2: Re: Tilapia Feed
from Jim Sealy Jr
Message 3: Tilapia sex reversal
from Adriana Gutierrez & Dennis LaGatta
Message 4: Re: Organic Farming
from doelle
Message 5: RE: what to feed Tilapia?
from doelle
Message 6: Re: Anti-Biotics
from KLOTTTRUE
Message 7: RE: what to feed Tilapia?
from JobieEagan@webtv.net
Message 8: all males
from Jose Pelleya
Message 9: FDA
from Jose Pelleya
Message 10: all males
from Jose Pelleya
Message 11: Re: Organic Farming
from KLOTTTRUE
Message 12: Re: Organic Farming
from William Evans
Message 13: Tilapia fingerling suppliers/prices
from S & S Aqua Farm
Message 14: Addendum - Tilapia fingerling suppliers/prices
from S & S Aqua Farm
Message 15: Re: Organic Farming
from JobieEagan@webtv.net
Message 16: RE: what to feed Tilapia?
from "Ronald W. Brooks"
Message 17: RE: Tilapia Feed
from "Ronald W. Brooks"
Message 18: RE: what to feed Tilapia?
from "Ronald W. Brooks"
Message 19: RE: FDA
from "Ronald W. Brooks"
Message 20: RE: Tilapia fingerling suppliers/prices
from "Ronald W. Brooks"
Message 21: Re: Organic Farming
from William Evans
Message 22: Jorg's e-mail
from "Uwe Bruenjes"
Message 23: Re: Jorg's e-mail
from KLOTTTRUE
Message 24: Integrated Systems Down Under!
from "Daryl Van Dyke"
Message 25: Re: Tilapia sex reversal
from "Sam Levy"
Message 26: Re: Tilapia sex reversal
from "Uwe Bruenjes"
Message 27: What to feed Tilapia?
from Colin Johnston
Message 28: Re: Organic Farming
from "TGTX"
Message 29: Re: Tilapia sex reversal
from Adriana Gutierrez & Dennis LaGatta
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Subject: Tilapia Feed
From: "Robert mabry"
Date: Wed, 07 Apr 1999 22:18:56 PDT
Jim Sealy wrote that he buys Clover Brand food for his Tilapia with a
28% protein content for $ .126/lb. How can this be? What part of
the world are you in? As someone trying to enter this business with
an indoor recirculation system, this price would be very encouraging
and could even help explain how some of you are apparently (and
surprisingly) able to grow Tilapia profitably in tanks. Is this
protein content animal or vegetable. I have seen numerous reports
cautioning against vegetable protein because of growout results and
lack of nutritional studies.
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| Message 2 |
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Subject: Re: Tilapia Feed
From: Jim Sealy Jr
Date: Thu, 08 Apr 1999 00:29:00 -0500
I buy this feed at the Tate County Co-op. That's the walk-in price
everyday. They don't care if I buy 50 lb. or 50,000 lb. at a time.
I've also bought Sunshine brand feed for about the same price, and am
surprised at the high prices I've seen quoted here. It may be that
people here buy so much more feed that the co-op and feed stores have to
sell at rock bottom prices every day. Just as a point of reference, I
figure we'll feed about 1,320,000 lb this year, and I'm a small timer by
Mississippi standards.
Oh.. Here = Senatobia, MS, USA at the top of MS Delta Catfish Country.
Something else that puzzles me.. I have 5 hatcheries within 80 miles
who deliver tilapia, and hybrid bream without it being any big deal.
I guess I'm just spoiled.
Jim
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Subject: Tilapia sex reversal
From: Adriana Gutierrez & Dennis LaGatta
Date: Thu, 08 Apr 1999 01:52:20 -0400
Trudy,
It is correct that Tilapia fry are fed testosterone laced feed to create
all-male fingerlings. While the process is called sex-reversal, I
believe that technically it is sex-defintiton as the fry are born
without sex clearly defined and the hormones simply help "steer" the fry
in the male direction. The USDA has not approved the process despite
all of the studies having been completed long aga at Auburn University.
I have heard the word "conspiracy" used in the discussions as to why
there hasn't been any approval. The amount of testosterone consumed in
the feed over the 3-week period is less than the testosterone produced
by an adult male tilapia over a day, I was told.
I know of a tilapia farmer who took all of the sex-reversal studies to
his vet who found the information on safety so compelling that he is
providing the farmer with testosterone for use in his fish. The farmer
has tried lots of cross-breeding and he says that it is difficult to get
consistent results. I suspect that there are other cooperating vets or
people buying testosterone ostensibly for their farm animals which is
then being diverted to the fish feed.
Adriana
> Probably feed laced with methyl-testosterone, a male hormone. This is a
> typical way of producing all-male stock but I believe it requires either a
> liscense or special permission for experimental use because it's a
> regulated drug. Perhaps others can correct me or elaborate. The
> alternative is to cross breed with hornorum males and either nilotica or
> mossambica females. These crosses produce predominantly (95%+) male
> offspring.
>
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Subject: Re: Organic Farming
From: doelle
Date: Thu, 08 Apr 1999 19:58:10 +1000
You probably forgot the main culprit. We are giving the children antibiotics
from very young age for pathetic little cuts bruises etc etc and thus reduce
our immune system.
We also spray everything with pesticides, which certainly have an efefct on
our metabolism and others.
We are not living a healthy life anymore. We 'old generation' are not
plagued as the young over the past decade.
We certainly know that chemicals have a vital effect on metaboli9c events in
our and mammalian bodies.
Just to add a few of the things important.
Furthermore do not forget, if you eradicate an insect eaten by a bird, the
bird also dies of malnutrition. The same with our diseases, immunity and diets.
Greetings Horst
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Subject: RE: what to feed Tilapia?
From: doelle
Date: Thu, 08 Apr 1999 20:23:23 +1000
At 08:34 PM 07/04/99 -0400, you wrote:
>I have another question concerning feed. Guess questions will never
>end. But I was told by a dealer that tilapia are fed a special mix for
>their first 30 days that cause all the fries to be males. After that
>they go to regular feed. Surely someone here can elaborate on that?
>Thanks again, Trudy
That smells like a hormone or other chemical in the feed !
Horst
Horst W.Doelle, D.Sc., D.Sc. [h.c.]
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Subject: Re: Anti-Biotics
From: KLOTTTRUE
Date: Thu, 8 Apr 1999 08:00:48 EDT
In a message dated 4/8/99 5:53:58 AM Eastern Daylight Time,
doelle@ozemail.com.au writes:
<<
You probably forgot the main culprit. We are giving the children antibiotics
from very young age for pathetic little cuts bruises etc etc and thus reduce
our immune system.
>>
Horst here is some encouraging news,I feel I must share with you,I have been
Injured a lot,Been hospitalized 17 times,had many operations,nd you are
right,the Doctors would always give me Anti-biotics,but in April 97,I had a
heart attack,had open heart surgery,I remember being amazed that I was not
given any anti-biotics,I asked my Doctor about it,and he explained about
creating superbugs.But I also remember,a guy in the Intensive care Cardiac
Ward where I was,was very close to death,because he had a real bad Infection
in his chest,after his Open heart surgery.May 98,Gall Bladder surgery,no
Anti-Biotics,Different Hospital,Different Surgeon, They don't all have deaf
ears, Cheer up it's not as hopeless as it seems. Ken
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Subject: RE: what to feed Tilapia?
From: JobieEagan@webtv.net
Date: Thu, 8 Apr 1999 08:08:40 -0400 (EDT)
Ron,
What would you think of this scenario? Hopefully I can find a breeding
farm that will sell me some reasonable breeders. If not, I start with
wild caught, get some experience, make my mistakes (guess more will come
even later) and then find some proven breeders for fast growth. Maybe
in 6 mo or so?
Thanks, Trudy
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Subject: all males
From: Jose Pelleya
Date: Thu, 08 Apr 1999 05:46:23 -0600
Trudy:
They are fed a mix which contains testosterone which causes them to not
develop female traits, and it's about a 95% success ratio.
Jose
At 08:34 PM 4/7/99 -0400, you wrote:
>I have another question concerning feed. Guess questions will never
>end. But I was told by a dealer that tilapia are fed a special mix for
>their first 30 days that cause all the fries to be males. After that
>they go to regular feed. Surely someone here can elaborate on that?
>Thanks again, Trudy
>
>
Thought for the day:
Indecision is the key to flexibility.
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Subject: FDA
From: Jose Pelleya
Date: Thu, 08 Apr 1999 06:00:20 -0600
Ron:
Costa Rica is the largest supplier of fresh filets to the US, something
like 5 million pounds a year, and it's FDA approved, so it's another
example of one hand not knowing what the other is doing, since the testing
arm of the FDA has not approved the M-T hormone for use in the US, and the
importing arm is OKaying the fillets from CR (and I'm sure all over the
world) which have used the hormone for sex reversal.
Logical, eh??
Jose
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Subject: all males
From: Jose Pelleya
Date: Thu, 08 Apr 1999 05:55:50 -0600
Gordon:
Here in Costa Rica it's the accepted way to reverse sex, no license/permit
needed.
The alternative breeding option is difficult unless you are sure of the
purity of the strain.
There are alternative methods, such as visuallly determining sex at a later
stage, and frying up the females (put the bitch on the barbie), or putting
a physical barrier with small holes in the tank, and as the females stay
small and can go through the holes you can cull them.
Jose
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Subject: Re: Organic Farming
From: KLOTTTRUE
Date: Thu, 8 Apr 1999 09:09:28 EDT
In a message dated 4/8/99 5:53:58 AM Eastern Daylight Time,
doelle@ozemail.com.au writes:
<< Furthermore do not forget, if you eradicate an insect eaten by a bird,
the bird also dies of malnutrition. The same with our diseases, immunity and
diets.
>>This is not an attack on anyones beliefs! This is not a put down!This is
not an agenda I have!This is not an attemt at Humor! This is not directed at
just Horst, I just used his statement as a starting point! I feel like I am
the least Intelligent person on this list!,so this is not a challenge to your
education! Many of you have my respect and admiration! So I have a question
here?
What's the big deal here?if you believe in Evolution,the insect and the bird
will change into something else!,if you believe in Natural Selection,So
What!,if you believe in Re-Incarnation,you're doing it a favor,it will come
back as something better !If you're American Indian,take it's spirit,and
carry-on!,If you're Christian,have faith that God is in control,and he is not
going to let anyone destroy his creation!,If you believe you're God,then just
fix it!,If you're an Animal Rights activist,then stop dragging the Whales
back in the water!,if you believe everything on earth has more importance
than mankind,then go find you a spot somewhere and just stand there,and don't
interfere with anything,if you're Atheist,Eat,Drink,and be merry!,you won't
have anyone to answer too! Why do you worry so much? Your fears and
concerns don't match up to your beliefs! Some of your beliefs will kill more
people than any bug or pollution or GE could ever kill! IT is Not what
You Believe that Matters! It Matters what You Believe!
Sincerely,Ken P.S. If anyone wants to address my questions on the list
or privately,please do, cuss me out,fuss me out,whatever,It will remain
private.
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Subject: Re: Organic Farming
From: William Evans
Date: Thu, 08 Apr 1999 06:55:47 -0700
doelle wrote:
>
> You probably forgot the main culprit. We are giving the children
antibiotics from very young age for
dont forget all the lousy adulterated vaccines. A DPT shot can be
deadly.
billevans
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Subject: Tilapia fingerling suppliers/prices
From: S & S Aqua Farm
Date: Thu, 08 Apr 1999 08:57:32 -0500
We're trying to update our tilapia supplier listings, and will be contacting
those we have identified for current pricing, etc. We'd also appreciate
input from list members.
If you are currently (or have investigated and plan to be) buying from a
particular supplier, could you forward name/address/contact/phone/email
information and also note the pricing you have been given/paying? We'd also
appreciate any comments you have as to the company's reliability, service,
fish quality, and other items you feel are important.
Thanks for your help, and I'll be glad to post a summary back to the list.
Paula Speraneo
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Addendum - Tilapia fingerling suppliers/prices
From: S & S Aqua Farm
Date: Thu, 08 Apr 1999 09:00:33 -0500
Sorry, I should have mentioned that we'd be interested in input from all
geographic areas, not just the U.S. Paula
------------------------------------------------------
We're trying to update our tilapia supplier listings, and will be contacting
those we have identified for current pricing, etc. We'd also appreciate
input from list members.
If you are currently (or have investigated and plan to be) buying from a
particular supplier, could you forward name/address/contact/phone/email
information and also note the pricing you have been given/paying? We'd also
appreciate any comments you have as to the company's reliability, service,
fish quality, and other items you feel are important.
Thanks for your help, and I'll be glad to post a summary back to the list.
Paula Speraneo
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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Subject: Re: Organic Farming
From: JobieEagan@webtv.net
Date: Thu, 8 Apr 1999 10:22:00 -0400 (EDT)
No, but I didn't mention the main antibiotic culprit. I have a great
doctor that agrees there is an overuse of antibiotics. Two sons have
never needed any and one only after he had surgery. Nor do we spend
more time in the doctor's office than necessary. Trudy
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Subject: RE: what to feed Tilapia?
From: "Ronald W. Brooks"
Date: Thu, 8 Apr 1999 10:42:39 -0400
Vpage
here is the link to Living Waters http://www.tilapia.net/fingerlings.html
this is to the page with info and prices on their fingerlings
Ron
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Subject: RE: Tilapia Feed
From: "Ronald W. Brooks"
Date: Thu, 8 Apr 1999 10:49:19 -0400
For those who live in an area with co-ops that carry fish feed that's
wonderful. My local co-op only carries a pond feed that is 21% protein and
the size is 9 mm way to large for my fish.
Which is a shame because it is .24 a pound. The silver cup feed I bought is
.36 a pound but shipping added .63 a pound. So if I could have picked it up
the cost would have been small. I tried to find catfish feed around here but
my local co-op looked at me funny.
Ron
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Subject: RE: what to feed Tilapia?
From: "Ronald W. Brooks"
Date: Thu, 8 Apr 1999 11:19:32 -0400
Sounds like a good plan. It is easier to take a loss of a small amount than
a large tank full of 1000 fingerlings.
I have a copy of the Illinois / Indian Aquaculture conference from 1995
it is wonderful and really goes into detail on recirculation systems and
breeding Tilapia. contact me off list and I will mail you a copy
Ron
The One Who Walks Two Paths
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Subject: RE: FDA
From: "Ronald W. Brooks"
Date: Thu, 8 Apr 1999 11:19:36 -0400
Jose
I try not to use words like common sense and logical when referring to my
government . they are mutually exclusive terms :~)
Ron
The One Who Walks Two Paths
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Subject: RE: Tilapia fingerling suppliers/prices
From: "Ronald W. Brooks"
Date: Thu, 8 Apr 1999 11:19:39 -0400
Paula
I buy from Living Waters Tilapia Farm
http://www.tilapia.net/fingerlings.html
They are very helpful , prompt and are willing to work with schools and
universities on small orders. And think nothing of a small order for someone
. They sell Pure line Nile and all male Pennyfish
Ron
The One Who Walks Two Paths
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Subject: Re: Organic Farming
From: William Evans
Date: Thu, 08 Apr 1999 09:58:42 -0700
In organic farming the organic material has to be
> broken down into inorganic componds and carried to the plant by water.
what about worms, and mycorrhizal fungi,?? these "elements" feed the
plant
as well.
.......
Plants can not absorb organic materals.
This cannot be true. Of the many ways in which plants can absorb
nutrient,
"endocytosis" has to be the most important.
Basically this is when the cell membrane pinches inward to create what
is called
a "vesicle"
a bubble , inside the cell. When the membrane does this it is able to
capture
whatever is outside the cell, whether it be a molecule of some varying
complexity,
or even a small particle.
In simple terms, if there is an "ideal" soil(organic), then a plant
existing
in that particular soil profile has the great privilege of going to the
larder
for whole foods , w/o having to assemble same from discrete
ions,
tho it is sure to do this as well as a backup or auxillary process.
billevans
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Subject: Jorg's e-mail
From: "Uwe Bruenjes"
Date: Wed, 07 Apr 99 11:56:39 PDT
Sorry folks, but due to my last computer problem I also lost Jorg's e-mai=
l. Somebody has it handy? By the way, where is Jorg; still on vacations?
Uwe
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Subject: Re: Jorg's e-mail
From: KLOTTTRUE
Date: Thu, 8 Apr 1999 13:57:30 EDT
In a message dated 4/8/99 1:33:38 PM Eastern Daylight Time,
uweb@megalink.net.mx writes:
<< Sorry folks, but due to my last computer problem I also lost Jorg's
e-mail. Somebody has it handy? By the way, where is Jorg; still on vacations?
>>
jdo@ucalgary.ca
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Subject: Integrated Systems Down Under!
From: "Daryl Van Dyke"
Date: Thu, 08 Apr 1999 11:09:44 PDT
Hello All-
In preperation for my trek to Australia, I'm canvassing for integrated
systems, aquaculture facilities, etc. I'd love the opportunity to check out
what is going on with this fascinating technology in Australia. I'd be
grateful for any leads, on any facilities; public, private, academic,
commercial, etc.
In general I'd love to get in contact with any Australian readers of this
list. I'd be happy to forward a list of replies (if you'd like that
published) to this list, as the results would probably interest the group.
Thanks for the BW, and have a synchronous day!
Daryl Van Dyke
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Subject: Re: Tilapia sex reversal
From: "Sam Levy"
Date: Thu, 08 Apr 1999 13:39:08 PDT
One of the main attractions of "sex reversal" (methyl testosterone)
is the consistency of the results when performed properly. That one
fact is what led breeders here (Israel) to use this technique quite
extensively.
Historically, problems kept showing up with all male production
through hybridization--there were some theories that held that the
genetic purity of the lines was the problem.
i believe that the major breeders today offer both sex reversed and
genetically produced monosex males.
sam
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Subject: Re: Tilapia sex reversal
From: "Uwe Bruenjes"
Date: Thu, 08 Apr 99 15:46:30 PDT
Hi Adriana,
how much of it is needed? I remember that you went to some kind of course=
where you learnt that.
Uwe
----------
The amount of testosterone consumed in
> the feed over the 3-week period is less than the testosterone produced
> by an adult male tilapia over a day, I was told.
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Subject: What to feed Tilapia?
From: Colin Johnston
Date: Fri, 09 Apr 1999 08:48:20 +0800
Trudy.
>I have another question concerning feed. Guess questions will never
>end. But I was told by a dealer that tilapia are fed a special mix for
>their first 30 days that cause all the fries to be males. After that
>they go to regular feed. Surely someone here can elaborate on that?
Work on sex-reversal of Tilapia and hybridization also is conducted at
the Asian Institute of Technology (AIT) and has been for many years.
Delegates to the World Aquaculture Society's conference in Bangkok
in 1996 were taken to AIT to see the process of feed formulation, but
whether this preparation would be acceptable in the States is not for
me to answer. There's also a British-based company FISHGEN with
links to Swansea University that has taken the hybridization route.
Both have web pages and may be easily accessed for greater detailed
information. I understand that FISHGEN have distributors in North
America, but in any case will accept orders directly from the UK.
Cheers
Colin
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Subject: Re: Organic Farming
From: "TGTX"
Date: Thu, 8 Apr 1999 19:48:42 -0500
> Dale wrote:
> > Plants can not absorb organic materals.
> Can you clarify this?
> Dave
Hi Dave and Dale and Everybody.
Here is a long passage from H.Resh's book on Hydroponics applied to the
question:
I enclose all of Resh's comments in quotes....And after I add my
comments...Hey.. it lets me practice my typing...
"The question of organic vs. inorganic gardening can be clarified by a
discussion of mineral uptake by the plant. In 1932, E. Munch of Germany
introduced the apoplast-symplast concept to describe water and mineral
uptake by plants. He suggested that water and mineral ions move into the
plant root via the interconnecting cell walls and intercellular spaces,
including the xylem elements, which he called the apoplast, or via the
system of interconnected protoplasm (excluding the vacuoles) which he
termed the symplast. However, whatever the movement may be, its uptake is
regulated by the endodermal layer of cells around the stele which
constitutes a barrier to free movement of water and solutes through the
cell walls. There is a waxy strip, the Casparian strip, around each
endodermal cell which isolates the inner portion of the root (stele) from
the outer epidermal and cortex regions in which water and mineral movement
is relatively free."
"If the root is in contact with a soil (nutrient) solution, ions will
diffuse into the root via the apoplast across the epidermis, through the
cortex and up to the endodermal layer. Some ions will pass from the
apoplast into the symplast by an active respiration-requiring process.
Since the symplast is continuous across the endodermal layer, ions can move
freely into the pericycle and other living cells within the stele."
"If a substance is moving across a cell membrane, the number of particles
moving per unit of time through a given area of the membrane is termed the
flux. The flux is equal to the permeability of the membrane multiplied by
the driving force causing diffusion. The driving force is due to the
difference in concentration ( the chemical potential) of that ion on the 2
sides of the membrane. If the chemical potential of the solute is higher
outside the membrane than inside, the trasport inward is passive. That is,
energy is not expended by the plant to take up the ion. If, however, a
cell accumulates ions against a chemical potential gradient, it must
provide energy sufficient to overcome the difference in chemical potential.
Transport against a gradient is active since the cells must actively
metabolize in order to carry out the solute uptake."
"When ions are transported across membranes, the driving force is composed
of both a chemical and electrical potential difference. That is, an
electrochemical potential gradient exists across the membrane. The
electrial potential difference arises from cations diffusing across more
rapidly than their corresponding anions of a salt. Thus, the inside will
become positive with respect to the outside. Whether the transport of an
ion is active or passive depends upon the contribution of both eht
electrical potential difference and the chemicqal potential difference.
Sometimes these 2 factors will act in the same direction, while in other
cases they act oppositely. For example, a cation migh have a higher
concentration inside the cell and yet be transported inward passivlely with
no energy expenditure on the part of the cell if the electrical potential
is sufficiently negative. On the other hand, anion absorption against both
a chemical potential gradient and a negative electrical potential would
always be an active process."
"There are a number of theories proposed to explain how respiration and
active absorption are coupled, but most of them employ the mechanism of a
carrier. For example, when an ion contacts the outside of a membrane of a
cell, neutralization may occur as the ion is attached to some molecular
entity tat is a part of the membrane. The ion attached to this carrier
might then diffuse readily across the membane, being released on the
opposite side. The attachment may require the expenditure of metabolic
energy and can occur on only one side of the membrane, while release can
occur only on the other side of the membrane. The ions separate and move
into the cell and the carrier becomes available to move more ions.
Selectivity in ion accumulation could be controlled by differences in
ability of carriers to form specific combinations with various ions. For
example, potassium absorption is inhibited competitively by rubidium,
indicating that the 2 ions use the same carrier or the same site on the
carrier."
"As previously indicated, the foregoing explanation of mineral uptake by
plant roots has been presented in an effort to clarify the question of
organic versus inorganic gardening. The existence of specific
relationships between ions and their carriers which enables their transport
across cell membranes to enter the cell demonstrates that mineral uptake
functions in the same manner whether the sourch of such minerals is from
organic matter or fertilizers. Large organic compounds making up soil
humus are not absorbed by the plant, but must first undergo decomposition
into the basic inorganic elements. They can be accumulated by their contact
with plant cell cell membranes only in their ionic form. Thus, organic
gardening cannot provide any compound to the plant which could not exist in
a hydroponic system. The function of organic matter in soil is to supply
inorganic elements for the plant and at the same time maintain the
structure of the soil in optimum condition so that these minerals will be
available to the plant. Thus, the indiscriminate application of large
amounts of fertilizers to soil without addition of organic matter results
in the breakdown of the soil structure and subsequently makes the abundant
supply of minerals unavailable to the plant. This is not the fault of the
fertilizer by the misuse of it in soil management"
O.K. I agree with the majority of what Resh says here, with a few very
important exceptions. He says that large organic compounds making up soil
humus are not absorbed by the plant. He is really correct about VERY LARGE
organic molecules, but small and medium size organics can be absorbed.. We
should ask the question....just how large are the inter and intra cellular
plant organic molecule carriers that he is referring to? And where do the
humic acid molecules in the soil come from? ...Right! Decomposed plants!
In any case, both the large, medium, and small organic acids in soils are
acting as carriers of nutrients in their own right. Humic and fulvic
acids, abundantly present in organic-rich soils, and on my aquaponic pea
gravel, ARE POLYELECTROLYTES. That means that they can act as carriers at
least up to the point of the plant root membranes....And perhaps beyond
that point, depending upon their size (molecular weight) These organic
acids range remarkably in size and weight....and they can chelate and thus
carry certain ions at many points along their long chain organic acid
"backbones" How many of you have ever tried the dye experiment with
celery in a glass..?.OK, I am cheating a bit, because the roots are more
selective than a broken plant stem...but you get the picture...the dye is a
small organic molecule....
Not only humic and fulvic acids, but the polysaccharides and other organic
molecules which are exuded by soil microorganisms and earthworms, and
fungi, etc., are acting in concert to "deliver", exchange, deposit, and
store these ions that Resh refers to.
I agree with Gordon Watkins that hydroponics might be regarded as organic
production, provided that nerve toxics such as organophosphorus and
chlorinated pesticides are not used in the production method, etc....I also
agree strongly with Gordon, that the nutrients from the hydroponics units
should find a stablized home somewhere once the hydroponic tanks are
dumped...all of that could be thought through and provided for via organic
means of stabilizing those nutrients in soils and biomass .....That is not
unfeasible for me......I could envision hydroponics falling into the realm
of organic production, since the simplest definition of organic, at one
time, before all the ancillary causes and the myriad swamp of bureaucratic
rider amendments were screamed for... was the conservation of soils,
nutrients, water, resources, etc,. and the prohibited use of excessively
toxic xenobiotic compounds which do not biologically degrade rapidly
enough.... those that can bioaccumulate up the food chain.... or those that
may have some other environmentally undesirable consequences beyond
toxicity, such as the estrogenic chlorinated compounds that caused egg
shell thinning in avian raptors and breast growth in male Sierra Club
members....but then, they exacerbated that 1000 fold by inhaling....
Eat more aquaponic greens!
Shalom, ya'll.
Ted.
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| Message 29 |
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Subject: Re: Tilapia sex reversal
From: Adriana Gutierrez & Dennis LaGatta
Date: Thu, 08 Apr 1999 21:23:50 -0400
Uwe,
I don't believe we went into that level of detail but I'm sure Jim
Rakocy can tell you. I suspect you can get testosterone in Mexico with
little or no problem.
Adriana
S&S Aqua Farm, 8386 County Road 8820, West Plains, MO 65775 417-256-5124
Web page http://www.townsqr.com/snsaqua/
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