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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| Message 1                                                           |

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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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| Message 3                                                           |

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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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| Message 4                                                           |

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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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| Message 5                                                           |

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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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| Message 6                                                           |

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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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| Message 7                                                           |

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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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| Message 8                                                           |

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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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| Message 9                                                           |

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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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| Message 10                                                          |

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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

| Message 11                                                          |

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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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| Message 12                                                          |

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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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| Message 13                                                          |

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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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| Message 14                                                          |

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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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| Message 15                                                          |

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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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| Message 16                                                          |

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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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| Message 17                                                          |

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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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| Message 18                                                          |

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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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| Message 19                                                          |

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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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| Message 20                                                          |

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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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| Message 21                                                          |

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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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| Message 22                                                          |

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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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| Message 23                                                          |

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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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| Message 24                                                          |

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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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| Message 25                                                          |

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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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| Message 26                                                          |

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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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| Message 27                                                          |

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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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| Message 28                                                          |

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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.

.------ ------ ------ ------ ------ ------ ------ ------ ------ ------.

| Message 29                                                          |

'------ ------ ------ ------ ------ ------ ------ ------ ------ ------'

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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