Saya punya beberapa informasi menarik seputar tumbuhan transgenic Bt. Saya
paste-kan salah satunya:
Bt Butterfly Concerns Take Flight Again
A new paper in the journal Oecologia has reawoken concerns that the pollen
from genetically modified maize plants containing the Bacillus thuringiensis
toxin may kill non-target insects. A paper by John E. Losey and colleagues
that appeared in Nature early last summer showed that in laboratory tests,
monarch butterflies (Danaus plexippus) fed milkweed leaves dusted with
so-called transformed pollen from a Bt-corn hybrid ate less, grew more
slowly and suffered a higher mortality rate. The new study, by Laura Hansen
Jesse and John Obrycki at Department of Entomology, Iowa State University
has investigated the effects of the Bt pollen in a situation more akin to
that experienced in agriculture. Obrycki says "Our study used naturally
deposited Bt corn pollen on milkweed plants. We counted the number of pollen
grains on plants before we exposed the leaves to the monarch larvae."
They found that larvae feeding for 2 days on milkweed plants dusted with the
"Bt pollen" showed higher mortality rates at both 2 and 6 days (between 20%
and 70%) compared to controls. Their analysis of the wind dispersal of Bt
pollen from maize fields, leads them to predict it may affect monarchs at
least 10 m from transgenic field borders, but those on milkweed plants in or
within 3 m of the edge will be most likely to be affected.
While Losey has stated that the experiment is an important next step,
representatives of the biotech industry have been quick to play down the
significance of the work.
Val Giddings of the US-based BioIndustry Organization said "Dr. Obrycki's
research stands in the shadow of more than 20 independent studies by widely
recognized scientific experts who have found that Bacillus thuringiensis
(Bt) corn does not pose a significant risk to the monarch butterfly," He
continued "This report considers only one small area of this complex topic
and the conclusions put forward by the authors stand in stark contrast to
those of the broader scientific community's research.
"The Oecologia paper is not truly 'field research' inasmuch as much of what
it reports is based on analyses taking place in laboratory manipulations
rather than field conditions. Furthermore, the paper clearly shows that
larval mortality was not correlated with the number of pollen grains on the
plant or the plant location within or at the edge of the field, surprises in
search of an explanation."
Giddings noted that the US Environmental Protection Agency (EPA) and the
Department of Agriculture have studied Bt corn for many years. The EPA has
just extended the registrations of these products through the 2001 growing
season and in April dismissed a Greenpeace lawsuit challenging the Bt plant
registrations on a lack of merit, stating '...available scientific data and
information indicates that the cultivation of Bt crops has a positive
ecological effect, when compared to the most likely alternatives.'
"To imply that Bt corn has a negative effect on monarch butterflies flies in
the face of the fact that last year, more than 28 million acres were planted
with Bt corn, an increase of approximately 40% over the previous year. In
the same time period, the monarch butterfly population flourished and
increased by about 30%, according to Monarch Watch."
Obrycki says that "the methods we used were replicated and do represent what
could occur at a larger scale." He also argues that "The population
densities of monarchs fluctuate for unknown reasons, I don't know that we
know enough about this species to predict that 20% of GM maize would have a
particular effect on its densities. He also points out that none of the
other studies cited by BIO have been published, making it hard to respond to
their claims.
National Corn Growers Association Chairman Roger Pine, said that "The
ecological effects are not unexpected, and are in line with other studies
that have been conducted," he said. "Second, these findings were based on
research using a single type of Bt, not all Bt traits. The Bt used in this
study is already known to express the insecticide at the highest level in
its pollen. Finally, corn hybrids incorporating this type of Bt trait are
not widely planted."
"NCGA fully supports the science-based decision making process currently
employed by the EPA in evaluating and approving Bt technology," Pine
continued. "NCGA supports continued evaluation of all agricultural
production techniques. However, we cannot evaluate these technologies in a
vacuum. We won't stop dead in our tracks, when a single study draws faulty
conclusions from unrelated scientific findings."
"No one wants to tell their children what monarch butterflies used to look
like. It's time that EPA insist that the companies selling Bt corn take
measures to protect monarchs and other butterflies from toxic pollen from Bt
corn," said Rebecca Goldburg, senior scientist at the environmntal
campaining group Environmental Defense.
In 1999, Environmental Defense asked EPA and Bt corn-producers to require,
through regulations or contracts with growers, that fields of Bt corn be
surrounded by 40-foot wide borders of non-Bt maize. Because most maize
pollen settles out within about a dozen feet of corn plants, "such borders
would dramatically reduce the flow of toxic pollen from Bt corn into
butterfly habitats" says the organization.
"Planting buffer zones of Bt-free corn is an effective and practical way of
protecting monarchs and other butterflies from toxic Bt pollen," said
Goldburg. "EPA already requires that farmers growing Bt corn plant 20% of
their corn acreage in non-Bt corn, in order to slow the evolution of pests
resistant to Bt toxins. Planting some or all of this 20% acreage as buffer
zones would be only a small additional step. Unfortunately, both EPA and the
companies selling Bt corn have refused to require buffers. This study showed
that "continued inaction would clearly be lethal to monarch butterflies,"
she concluded.
Obrycki concludes "I think there needs to be a serious examination of the
need for Bt maize for the management of the target pest - the European corn
borer. As well as a serious examination of the non-target effects of this
biotechnology"
The paper, "Field deposition of Bt transgenic corn pollen: lethal effects on
the monarch butterfly" by Laura C. Hansen Jesse and John J. Obrycki appears
in Oecologia
For regular updates on issues relating to GM plants containing the Bt toxin,
visit the topic on Bt: resistance and other issues:
http://www.agbiotechnet.com/topics/plants.asp
Contact: John Obrycki, Iowa State University, Dept of Entomology, Ames, IA
50011 USA
Tel: 1 (515) 294-8622
Fax: 1 (515)-294-4431
Email [EMAIL PROTECTED]
URL: http://www.ent.iastate.edu/
Kalau sudah pernah ada, kenapa nggak dibaca dulu hasil confference-nya?
Atau kalau ada yang punya mungkin bisa dibagi-bagikan sama yang lain? Kalau
ada pemikiran yang baru, baru didiskusikan lagi. Saya khawatir proses
perkembangan wacana kita cuma melingkar-lingkar terus.
Mungkin Mbak Tuti bisa nolong menyebarkan point-point utama materi
conference WB yang FAQ (Frequently Asked Questions)? Atau mungkin di web
ada informasinya?
Pertanyaan-pertanyaan baru kan bisa lewat e-mail, cc. ke mailing-list ini.
Saya yakin WB mau menjawabnya, nggak harus ngeluarin biaya pesawat kan.
Uangnya lebih bagus disumbangkan ke yang lebih membutuhkan (saya misalnya
:-)).
Salam,
ic.
----- Original Message -----
From: "Tuti Hendrawati" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: 11 September 2000 20:26
Subject: Re: [lingkungan] Patrick moore, rekayasa genetika dan Greenpeace
> World Bank pernah mengadakan conference mengenai hal ini dan pembicaranya
semua
> mengemukakan berbagai pendapat tentang penerapan bioteknologi di negara
> berkembang. Pembicaranya merupakan pakar-pakar bioteknologi dari United
Kingdom
> dan Universitas-universitas di USA yang concern terhadap hal tersebut..
> Barangkali Bang RL melalui WB bisa mengundang mereka ke Indonesia?
> ...maaf...cuma usul nih. Habis siapa sanggup ngeluarin USD lagi jaman
repot
> begini? Kalau Patrick Moore kan sponsornya sudah jelas.
>
> Tuti
>
>
>
>
> > Nah ini baru ide cemerlang! Ayo siapa yang mau me-mediasi?
> >
>
>
> --
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>
>
>
>
>
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