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July 12, 2000


Questions, Organic yields, EU standards, GM Herbicides,


AgBioView - http://www.agbioworld.org, http://agbioview.listbot.com

Subj: Questions
Date: Thu, 13 Jul 2000 2:02:57 AM Eastern Daylight Time
From: "Sudha Mysore"

I am an economist working on agricultural crop related problems in India.
I seek clarifications for the following questions.

(i) What is the difference and implecations between ' research on
a gene ' and research around a gene or gene sequence which is protected ?

(ii) If a farmer or a farmer organisation develops a variety which
is a biological mutant of an existing improved variety, can it be
protected and if so which is the best method?

(iii) In Uruguay round of Trade negotiations one important clause has
been included. It is the 'Market access' clause. Which means that the
member countries will have to provide additional market access to other
members to a tune of up to 2 % every year with reduced tariff rates. If
such a clause is introduced, the producers from the developing countries
may incur heavy losses due to increased produce of better quality
available domestically. Is it true and what are the actual implications
of such a clause?

Thank you.

Date: Jul 12 2000 07:46:17 EDT
From: "Tony Trewavas"
Subject: organic yields

Organic yields.

This is in reply to Klaas Martens.

Dear Klaas

I feel I am being conned somewhere along the line. The yields for N fixed
/ hectare are quoted in Chrispeels and Sadava Plants Genes and Agriculture
page 454 2nd edition and they quoted them directly from a book published
in 1966. 200Kg/ha. Nitrogen is nitrogen, it can only be in protein in
clover and only in protein in corn (at least equivalent for equivalent; I
am aware there are other nitrogenous compounds). So 1Kg of protein N in
clover can only produce 1 Kg of protein N in corn. We are also not using
metric tonnes which I assume are 1000Kg so I think this needs
clarification from you. Also yields of alfafa must depend on climate And
position because soil temperature will determine rates of N fixation. So
where your figure of 17000kg/ha comes from I am not sure and I think we
need to start again and go through the calculations. Can we get agreed
units and can you check the figures I have quoted to you again for N
fixation. Are we talking about elemental nitrogen or amino acid nitrogen?
Incidentally I see that corn is normally about 10%
protein so that would reduce my estimate even more. Can we also state
exactly which part of the world we are talking about as well because
yields vary enormously according to soil and climate.

It looks as though we are talking about different methods of management
and I would still favour ICM which is flexible in approach. Organic
yields have been compared here (UK) by CWS systems and LEAF who run
organic farms alongside ICM and find that N is lacking during canopy
growth by using green

kind regards

PS about 15 people have told me that alfafa is not a semitropical crop.
Thanks for teh replies
Anthony Trewavas FRS
Institute of Cell and Molecular Biology
Mayfield Road
University of Edinburgh
Edinburgh EH9 3JH
Phone 44 (0)1316505328
Fax 44 (0)1316505392
email Trewavas@ed.ac.uk
web site http://www.ed.ac.uk/~gidi/main.html
To view the web site simply click on the address

Date: Jul 13 2000 07:07:05 EDT
From: "Tony Trewavas"
Subject: further on organic yields

To Klass Martens

Dear Klass

Some further information on organic yileds where I live (UK). Organic
in the UK envisages normally a five to six year rotation with 2-3
years of grass clover ley. If ther is no lvestock on the farm that
land is effectively set aside and produces nothing except fixed

Fixation of atmospheric nitrogen is 10-80 kgN/ha/y over most crops
and 80-280 kgN/ha/y over a clover rich sward. But a well grwon crop
of potatoes (60 ton/ha wet weight) takes 160 kg N/ha off the field in
tubers. Potato is the most efficient converter of light to dry
weight if I remember my elementary physiology (but check). A 5
ton/ha crop of spring barley would remove about 85kgN in the grain
and perhpas 40 kg N in the straw. It can be calculated that a 60
ton/ha potato crop would remove 29, 338, 12, 4, and 5 kg/ha of P, K,
Mg, Ca, and Na. Average depostion of these minerals by rainfall is
0.5, 4.0, 4.1, 11.4,33 Kg/harespectively. If these mineral ar not
replaced by applciation then they are merely recycled by gren manure.
So the history of any soil is important to understanding its organic
yield. I don't know of any instances of winter legume growth in the
UK although they might do so down south but frost would probably
kill throughout the UK.

The record yiled of corn that I have seen in an article in Science is
20tons/ha. i don't think the figures match that at all for organic
yields. Direct comparison between organic agriculture and
conventional and it is necessary to compare plots on teh same farm
were reported ina paper in Nature in 1998 which i can look up but
were 7tons/ha. Average corn production in the US seems to be
7tons/ha. organic is still well short and I think here we have to
deal with what is feasible by many farmers rather than records. Thus
the article in the Scientific American I quoted indicated that 5
people/ha were fed by traditional organic; in China there are now 15
people/ ha of arable land.

I suppose it is as well to remember that the IRRI in the Philippines
has had taken three crops/year from a rice field for the last 30
years without loss of yield which I believe is 14 tons/ha.

Kind regards

Anthony Trewavas FRS

Dear All,

One point that is continually ignored by the anti-GM lobby is the
existance of long terminal repeat retrotransposons in vertebrates,
invertebrates and plants. There are at least 32 retroelements in plants.
At least one family (Endovir) has ORF's which code for a transmembrane
protein. These are found in Arabidopsis, pea, soybean and maize
(Peterson-Burch et al, TIG, April 2000).

These sequences have probably been jumping genomes between insects and
plants for millions of years (conserved regions in both plants and
insects). Peterson-Burch et al., state; "...because of their ability to
occasionally transduce cellular genes, are a potent vehicle for
interspecies gene flow in plants."

It is likely that many more of these retroviral footprints will be found
as genomes are sequenced and searched. Therefore there is plenty of
evidence that gene insertions occur naturally. Some of these will be fatal
and, like transgenic plants, individuals will not germinate or survive to
reproduce. Infertility is common in tissue culture grown plants (whether
transgenic or not). Some may have novel effects, some toxic ,but most
neutral. If this were not the case then every generation of plants would
have a good chance of poisoning somebody somewhere. This doesn't happen
because genomes don't self-destruct whenever a novel genetic sequence is
inserted. The evidence is overwhelming because most people can eat most
crops safely. It is also theoretically extremely unlikely that a novel
genetic element would be inserted in frame and with the correct ribosome
binding sequences and termination sequences to produce a novel protein.
Even if chimeric proteins were produced the VAST majority would be no more
than an extra source of protein. It is not easy to design a protein to
behave as a toxin even if you know a lot about toxins. The plant knows
nothing about proteins and if it behaves as if nothing has happened then
you can bet your life nothing has.

Malcolm Livingstone
CSIRO Tropical Agriculture
The views expressed here are entirely my own and in no way reflect those
of my employer, CSIRO.
Malcolm Livingstone

Subj: RE: EU standards, Scientist?, labeling
Date: Tue, 11 Jul 2000 3:31:53 PM Eastern Daylight Time
From: "Julian Morris"

So far as I am aware, animal antibiotics are not known to have led to any
significant cases of antibiotic resistance in humans. Antibiotic
resistance is an inevitable by-product of antibiotic use but is enhanced
by over-prescription and failure to complete courses of human antibiotics.
Use of antibiotics in animals may have led to a small increase in
resistance to food-borne bacteria such as E-coli, but even for this there
is not much evidence.

However, the EU is not entirely to blame for the scare. As Roger Bate
documents in his chapter in Fearing Food (Butterworth-Heinemann, 1999),
animal antibiotics were first banned in Denmark and Sweden following
scares about the impact of their use in those countries. Following this,
various bodies, including the British House of Lords Select Committee on
Sicence and Technology, recommended teh phase-out of animal antibiotics.

Governments should stop giving the pretence that they are regulating the
food that we eat. State regulators have failed to prevent the very kinds
of food hazards (E.coli poisoning being one example) that they are inteded
to prevent. By contrast, private companies have strong incentives to
ensure that the food they sell is safe. Consider the recent example of
Tesco removing E.coliu infected mushrooms from its stores and informing
consumers (even though the E.coli turned out to be relatively benign). The
problem is that by giving the pretence of regulation, governments
discourage consumers from discriminating between safe and unsafe foods on
the basis of reputation. This has a knock-on effect on producers who are
discouraged from investing in reputation-building safety. The perverse
result is that the food we eat is less safe than would be the case without
the regulations.

Julian (MA Econ, MSc Env. Econ, MPhil Land Econ, Grad Dip. Law -- an
economist and a lawyer who can spot a good argument when he sees one and
who is enough of a statistician to know that at a 5% level it is
impossible to reject the null hypothesis that 99% of statistics are bunk)

This was posted in a list of latinamerican agricultural scientists. Any

Josť Falck Zepeda


Published on Sunday, July 2, 2000 in the London Observer

Going Backwards: US Prepares To Spray Genetically-Modified Herbicides On
by Ed Vulliamy in New York

A torrent of potentially lethal herbicide is set to be unleashed across
great swaths of Colombia as part of a new US aid package which was finally
approved by Congress last week.

A hidden and undebated condition of the $1.6 billion package - meant to
finance the Colombian government's fight against the now overlapping
forces of guerrilla rebels and narco-cartels - is a plan for military
aircraft to
spray the country's coca-growing areas.

The scheme echoes the infamous defoliation of Vietnam because the plan
involves a mycoherbicide called Fusarium EN-4. The Fusarium fungus is the
root for many of the chemical weapons developed by the US, the Soviet
Union, Britain, Israel, France and Iraq.

Mycotoxicologist Jeremy Bigwood - working with a fellowship grant to carry
out research into Fusarium derivatives used in biological warfare - told
The Observer that the use of the fungus in Colombia would damage crops
other than cocaine, and develop mutations that could lethally affect
humans with immune deficiencies.

Fusarium works by infecting crops with a soil-borne mould which secretes
toxins into their roots, which then putrefy and dissolve the plants'
cells, killing them or - worse still - affecting the animals or humans
who feed
off them. During the late 1980s, a mystery epidemic of Fusarium suddenly
attacked a coca-growing area of Peru. Bigwood was working as a
photo-journalist and teamed up with a Latin American expert, Sharon
Stevenson, to publish an article in the Miami Herald detailing extensive
damage to other crops than coca in the Peruvian valley.

Ruined peasants said they had seen helicopters spraying a brownish smoke
across the fields, but it remains a mystery whether the Fusarium epidemic
was an experiment by the US and Peruvian authorities, as Bigwood and
Stevenson suspected.

Fusarium next emerged in 1999 when Colonel Jim McDonough - a former
colleague of White House drug czar General Barry McCaffrey, now in charge
of the present Colombian operation - was hired by Governor Jeb Bush to run
the Florida anti-drug office. He proposed to spray the fungus's EN-4
strain on the state's copious marijuana crops. His adviser in the scheme
was Dr David Sands, now a professor at the University of Montana in
Bozeman, who had extracted the strain for the US Department of

The plan was scotched when the head of Florida's Department of
Environmental Protection, Dr David Struhs, wrote a letter to the colonel
dated 6 April 1999, saying that the 'mutagenicity' of the fungus 'was by
far the most disturbing factor in attempting to use a Fusarium species as
a herbicide. It is difficult if not impossible to control the spread of
the Fusarium species,' he wrote. 'The mutated fungi can cause disease in
a large number of crops including tomatoes, peppers, flowers, corn and
vines'. He added that the mutated genus could stay in the ground for 40

During research for his lecture, Bigwood traced Sands to Colombia where
he was an executive with Agricultural and Biological Control, a company
which markets the fungus. He visited scientists to tell them about EN-4,
and -
according to the same scientists' accounts to Bigwood - instructed them
not to talk to the press.

The government's 'fumigation' of coca-growing areas of Colombia had been
continuing for some time on a small scale, with Indians in the high Andean
villages complaining of nausea, rashes and stomach problems after the
spray-planes had swooped over. They have also damaged legitimate crops,
thereby undermining government efforts to support farmers who have
renounced poppy and coca growing.

The agent used in these cases was Glyphosate, marketed by the Monsanto
company (famous for GM foods) as 'Roundup'. Monsanto had been forced by a
court case in New York to withdraw claims that the product was 'safe,
non-toxic and harmless'.

The limited spraying programme did nothing to curb the mass production of
either cocaine or heroin. Official sources fear even if the forthcoming
programme were to wipe out a third of the drug, that would send the price
of the remaining two-thirds 'through the ceiling'.

US government researchers, says Bigwood, initially insisted that the EN-4
strain was 'species specific', designed to attack only the Erythroxylum
genus in a coca plant. But, he says, there are 200 other plant species
within that genus which do not contain coca and could therefore be
affected and destroyed. Even this does not fully define the threat to
other crops because, says Bigwood, 'it mutates into another organism,
capable of attackinganother plant. The protagonists of Fusarium can then
hide behind the fact that when it attacks something else, it has become
something else.'

Bigwood's greatest concern is with the potential effect not on other
crops than coca, but on humans. Among the Colombian scientists who met
with Sands was Eduardo Posada, president of the Colombian Centre for
Physics, who found Fusarium to be 'highly toxic'. His data found that
that the mortality rate among hospital patients who were immune-deficient
and in-fected by the fungus was 76 per cent.

'To apply a mycoherbicide from the air that has been associated with a 76
per cent kill rate of hospitalised human patients would be tantamount to
biological warfare', he said.

© Guardian Newspapers Limited 2000