GENET archive

[Index][Thread]

2-Plants: Indian Bt gene monoculture, potential time bomb



                                  PART I
-------------------------------- GENET-news -------------------------------

TITLE:  Govt study spies genetic cotton faults
SOURCE: The Telegraph, India, by G.S. Mudur
        http://www.telegraphindia.com/1050727/asp/nation/story_5039613.asp
DATE:   26 Jul 2005

------------------- archive: http://www.genet-info.org/ -------------------


*.........................................................................*
please download the study at:
http://www.ias.ac.in/currsci/jul252005/contents.htm
Temporal and intra-plant variability of Cry1Ac expression in Bt-cotton
and its influence on the survival of the cotton bollworm, Helicoverpa
armigera (Hübner) (Noctuidae: Lepidoptera)
K. R. Kranthi, S. Naidu, C. S. Dhawad, A. Tatwawadi, K. Mate, E. Patil,
A. A. Bharose, G. T. Behere, R. M. Wadaskar and S. Kranthi
Current Science Vol. 89 No. 2 25 July 2005
*.........................................................................*


Govt study spies genetic cotton faults

New Delhi, July 26: Government scientists have acknowledged flaws in the
genetically modified Bt cotton plants under commercial cultivation,
virtually endorsing what non-government organisations have been claiming
for long.

However, biotechnology company Monsanto, which provided the technology to
create the plants, said Bt cotton had gained acceptability among farmers
and done well in the past three years.

The Bt cotton varieties are designed to make a protein, cry1Ac, that
kills bollworms when they gorge on the plants. But scientists at the
Central Institute of Cotton Research have reported that the amount of
protein is not always enough to kill the insects.

In a study released yesterday, the Nagpur-based scientists said the
amount of protein varies across different varieties and, in some plants,
decreases to levels that are inadequate to protect the plants 110 days
after sowing.

Their experiments also revealed that production of the protein is lowest
in the bollworms' most favoured sites of attack -- the plants' ovaries
found in the flowers and the thick green peel of the cotton boll from
which cotton blooms.

"The most vulnerable parts of the plants thus do not have adequate cry1Ac
to kill the pest," said Keshav Kranthi, a senior scientist at the
institute of cotton research and lead investigator of the study published
in the journal Current Science.

These findings, the researchers said, explain farmers' complaints that
bollworms survive on Bt cotton plants. Farmers would have to be "mentally
prepared for the possibility of extra applications of insecticides to
control bollworms," a scientist said.

The pest-killing ability of the Bt cotton varieties stay intact for about
110 days, the study showed. But cry1Ac levels decline steadily as the
plants grow and drop to below the critical "lethal level" of 1.9
micrograms by 110 days.

"This study validates our findings and proves that Bt cotton in India was
approved without adequate field testing," said Suman Sahai, director of
Gene Campaign, a New Delhi-based NGO that has been demanding greater
transparency in genetic engineering issues.

Sahai said India's regulatory agencies should have ascertained whether
the plants produce the protein in the right amounts and on the right
sites in the plant before approving it for commercial cultivation. "Why
weren't rigorous studies such as this one conducted earlier?" she asked.

"We're now asking ourselves the same question," a government entomologist
said.

The Bt cotton plants carry a gene from a bacteria called Bacillus
thurigiensis (Bt) that allows the plants to produce the cryAc1 protein
which is toxic to bollworms.

A spokesperson for Monsanto said Indian farmland under Bt cotton has
grown from 72,000 hectares in 2002 to over 1.2 million hectares in 2004.
Last year, over 350,000 farmers had planted Bt cotton.

"A majority of farmers in India have managed crops with minimal
insecticide sprays for control of bollworms," the spokesperson said.

But the research institute data shows that Bt cotton in India may require
more supplemental insecticide sprays than Bt cotton elsewhere in the world.


                                  PART II
-------------------------------- GENET-news -------------------------------

TITLE:  Indian Bt gene monoculture, potential time bomb
SOURCE: Nature Biotechnology 23: 158, by K.S. Jayaraman, Jeffrey L. Fox,
Hepeng Jia & Claudia Orellana
DATE:   Feb 2005

------------------- archive: http://www.genet-info.org/ -------------------


Indian Bt gene monoculture, potential time bomb

K.S. Jayaraman1, Jeffrey L. Fox2, Hepeng Jia2 & Claudia Orellana2
1 Hyderabad
2 Additional reporting by Jeffrey L. Fox in Washington, Hepeng Jia in
Beijing and Claudia Orellana in Brecon, UK, for Latin America.

Increasing reliance on a single gene in growing a variety of crops to
make them resistant to bollworms could be dangerous, warn experts.
Resistance is looming large among Bt crops in India.

In March, this year, an unprecedented number of hybrids of Bacillus
thuringiensis (Bt)-resistant cotton will be planted in India. A recent
model simulating the development of insect resistance to Bt cotton
predicts that such monoculture could lead to resistance within a few
years. The risk of resistance as a consequence of gene monoculture is
higher in India where Bt crops are planted illegally than in other
countries producing transgenic crops.

Next month 12 new Bt cotton hybrids will enter the Indian market--all
carrying the same cry1Ac gene licensed from US seed giant Monsanto. Four
of the six Indian companies that have licensed the gene--including Mahyco
in Jalna, Raasi Seeds in Attur, Ankur Seeds Limited in Nagpur and
Nuzhiveedu Seeds in Hyderabad--will each release three Bt hybrids. Bt
cotton carrying cry1Ac to confer resistance against bollworms
(Helicoverpa armigera) was initially exclusively licensed to Jalna-based
Maharashtra Hybrid Company--also known as Mahyco--the Indian partner of
Monsanto of St. Louis, Missouri, in 2002 (Nat. Biotechnol. 20, 415, 2002).

Keshav Kranthi, a senior scientist at the Central Institute for Cotton
Research in Nagpur in the Indian province of Maharashtra and colleagues,
warned of the risk of pest resistance to Bt varieties currently used in
India in a paper published in the Indian Academy of Science publication
Current Science 87, 1593_1597 (2004) last December. The authors
established a theoretical model to predict resistance development in
bollworms due to overuse of the cry1Ac gene. The 'Bt-Adapt model'
simulates the bollworm's adaptation to the toxin, depending on the number
of generations of the insect exposed to Bt every year and on the number
of different Bt crops the insects encounter.

The first estimate is based on two to three generations of insects
exposed each year to a single Bt crop. "If the area under Bt cotton gets
to 70_80% in a 100_200 kilometer radius, our model estimates resistance
development [in] 3_4 years," Kranthi said. "So, it wouldn't be surprising
to find Bt-cotton crop failures in some parts of India, starting with [in
the province of] Gujarat in a couple of years from now," he adds.

But the Bt-Adapt model can also predict the consequences of exposing
bollworms to more than one Bt crop (e.g. cotton and potato). If the
number of generations of insects exposed to Bt crops increases to five or
six--a likely scenario when another Bt crop is included--the rate of
resistance development, according to the model, would be accelerated to
half the time it now takes with only Bt cotton.

This scenario is not so unlikely given the increasing reliance on cry1Ac
in other crops in India. "Over 42% of the projects in biotechnology
research use this Bt gene," says Suman Sahai, convener of Delhi-based
Gene Campaign, a nongovernmental organization, and visiting professor of
genetics at Hamburg University. "We are going to face a situation when a
wide range of crops, from cotton to potato, rice, maize, brinjal
[eggplant], tomato, cauliflower, cabbage, even tobacco, carrying the Bt
gene will be growing next to each other," warns Sahai.

By contrast, other countries have made limited use of the gene, and have
refugia and monitoring strategies. Commercial crops with the cry1Ac gene
in the US are limited to cotton and corn, and the gene has been used in
research on potatoes. China is using cry1Ac in at least one of the three
GM rice crops for which approval has been sought for commercial release
(Nat. Biotechnol. 22, 642, 2004) and in its commercialized cotton, which
was individually developed both by Monsanto and by its own scientists.
Meanwhile, Argentina, Columbia and Mexico grow the Monsanto Bt cotton
commercially and Uruguay and Brazil carry out field trials. Currently,
the potential for illegal planting and associated resistance outbreak is
the strongest in Brazil.

Though no resistance breakdown has been observed in fields in India yet,
"it is important to remain guarded," warns Kottaram Krishnadas Narayanan,
managing director of MetaHelix, in Bangalore, a crop biotechnology
company. "Genetic uniformity is really dangerous," adds Says Ebrahimali
Siddiq, board member of the International Rice Research Institute in
Manila, the Philippines. "Resistance can break down any day."

"This kind of a situation is unique to India," explains Kranthi. Until
now, a refugia strategy, not strictly implemented and widely undermined
by illegal planting of Bt cotton, was the only strategy to avoid
resistance in India (Nat.Biotechnol. 22, 1333_1334 (2004)). "Unlike the
US, non-Bt cotton refuges are not required in India," explains Bruce
Tabashnik Professor at the Department of Entomology at the University of
Arizona in Tucson. "If all or most of the other crops eaten by
Helicoverpa armigera produce cry1Ac and cotton produces cry1Ac, refuge
production of susceptibles might not be adequate to stem resistance."

Fears of early resistance development due to gene monoculture is already
forcing Monsanto to develop stacked genes thus shifting the focus to
other genes. And Syngenta India, in Pune, started to develop cotton with
an unrelated type of Bt toxin (vip3). "We need other genes not only to
delay resistance but to bring seed price down through competition,"
concludes Prabhakara Rao managing director of Nuzhiveedu Seeds.


                                  PART III
-------------------------------- GENET-news -------------------------------

TITLE:  Govt-approved seeds not up to expectation
SOURCE: Newindpress, India
        posted by Checkbiotech, Swqitzerland
        http://www.checkbiotech.org/root/index.cfm?
fuseaction=newsletter&topic_id=2&subtopic_id=9&doc_id=10852
DATE:   25 Jul 2005

------------------- archive: http://www.genet-info.org/ -------------------


Govt-approved seeds not up to expectation

RAICHUR - Despite the recommendations of agriculture department officials
to use boll guard cottonseeds like Mahco BT, Rasi BT and Banni BT
varieties for better yield, most farmers have opted for private boll
guard BT seeds. The officials insist that the private seeds are spurious
and warned traders against selling them.

But the ground realities are different. The officially recommended Banni
seeds have shown 48 per cent germination, Rasi seeds 65 per cent and
Mahyco seeds 70 per cent germination.

Whereas the private BT seeds has shown 90 per cent germination this time.
Though the officially recommended seeds gave good yield of cotton last
year, this time it has failed at the germination stage itself.

Farmers of villages in Yergera, Ashapur, Gunjalli, Nelhal, Dinni,
Merchetal, Udumgal, Jalibenchi, Kamalapur, Matmari, Poortipli,
Garaladinni and Heerapur, Ganmur Shakavadi, Kadgamdoddi, Chandrabanda and
Palvaldoddi in Raichur taluk, Kallur, Gorkal, Kurdi, Kapgal, Hokrani in
Manvi taluk have all gone for cotton crop, particularly bollguard BT
cotton variety. The BT variety has attracted farmers because it prevents
heliothis disease.

Last year also farmers from Udumgal and Ganadinni complained of the
officially recommended Mahyco BT seeds. While private BT seeds are
available in the market at Rs 400 to Rs 500 per pocket of 750 gms, Banni
seeds cost Rs 1,818 per 450 gm pocket, Raasi Rs 1,460 per 450 gm and
Mahyco seeds are Rs 1,450 per 450 gm.

The farmers said that the Mahyo BT seeds do not have resistance power.
The seeds would affect germination if the rains were not on time or even
with excess rains.

Besides, the recommended seeds demand more land as the experts suggest
that non BT seeds would have to be sown around the actual crop to avoid
spreading heliothis. If the BT seeds can prevent heliothis disease, why
this fear, the farmers ask.

Many farmers allege that experts from the agriculture college here are
silent over the failure of the recommended seeds. Officials always
suggest vague ideas with no clarity, keeping the farmers in the dark.

As a result, though the farmers have gone in for cotton in more areas,
the yield would be less as the germination itself was not encouraging.


--


GENET
European NGO Network on Genetic Engineering

Hartmut MEYER (Mr)
In den Steinäckern 13
D - 38116 Braunschweig
Germany

P: +49-531-5168746
F: +49-531-5168747
M: +49-162-1054755
E: coordination(*)genet-info.org
W: <http://www.genet-info.org>



-----------------------------
   GENET-news mailing list
-----------------------------