Post on 20-Jun-2022
Twenty years of GM varieties use: Lessons learnt
Dr. Michel FOK
CIRAD (France) and ICRA
Michel.fok@cirad.fr
The use of Genetically modified varieties (GMV) dates back to 1997 and spreads to 26 countries out
of which 18 are recording more than 50,000 ha and 11 more than one millions hectares. According to
ISAAA (International Service for the Acquisition of Agri‐biotech Applications), the sole source of stats
related to the use of GM varieties, the total acreage covered has been increasing continuously over
the period of twenty years, as well as the number of countries concerned. This quantitative evolution
is claimed to be a clear indication of the global positive impacts of the use of GM varieties. This
criterion is complemented by other claims related to the global decrease of the pesticides use, global
production increase and economic gain and reduction of greenhouse gas emission.
The positive impacts claimed at global level are encountered also at the individual level of a country
such as Australia. The country specificity of high yield has been preserved. The savings in the
insecticide use is claimed to be the most positive impact of GMV use. This savings resulting from
GMV use is illustrated by the reduction of the amount of active ingredient per hectare, but the shift
to new generation of insecticide ingredients which are effective at much lower dosage has
contributed as well, if not more than the GMV use.
There are nevertheless negative impacts which are well documented and which used to be
overlooked by those who advocate a further extension of the use of GMV. Where pest resistant GMV
are used, the pest complexes have shifted and have implied the need to chemically control pests
whose earlier infestation level did not require. Where herbicide tolerant GMV have been used
(mainly tolerant to glyphosate), glyphosate resistant weeds have emerged, with a continuously
increasing number of weed species. The resulting increase of the pesticide control cost, along the
high and increasing cost of seeds, has implied a reduction if not a reversion of the profitability in
using GMV. Australia is a rare exception of country where the mentioned negative impacts are not
documented, thanks to a particular coordination among a small total number of cotton growers
(around 1,000), which nevertheless has not prevented them to pay the highest fees for the right of
using GMV.
Lessons from the effects observed are fourfold. First, it is worth debating again the issue of
effectiveness of the genes used so far in GMV, by distinguishing short term and mid‐term effects, as
the effects could reverse 5‐6 years after the commercial release of the varieties. Second, the
assessment of the impacts of GMV which overlooks distinct short term and mid‐term effects, as
those commonly implemented globally or at the level of a country, does not help to capture reality
and could be misguiding. Third, the ecosystem reacts to the way GMV are being used; the pest
complex shift and the emergence of weeds resistant to herbicides are illustrations of ecological
reactions to the mis‐management of GMV use based on general and continuous use. Fourth, if GMV
were to be used, the best way is partial use.
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20 Years of GM varieties useLessons learnt
Michel FOKmichel.fok@cirad.fr
13th Meeting of the Inter‐regional Cooperative researche network on cotton for the Mediterranean and Middle East regions
Luxor, Egypt, February 2‐6, 2018
Michel FOK, Luxor, Egypt, Feb. 2018 1
Presentation plan
• The use of GM varieties sounds good
• Negative impacts observed too
• Lessons to retain
Michel FOK, Luxor, Egypt, Feb. 2018 2
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The use of GM varieties sounds good
• At the world level
– Information extracted from ISAAA
• International Service for the Acquisition of Agri‐BiotechApplications
• Report freely available at http://www.isaaa.org
Michel FOK, Luxor, Egypt, Feb. 2018 3
Acreage is continuously increasing
Michel FOK, Luxor, Egypt, Feb. 2018 4
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Use is encountered in all continents…with 5 major countries
Michel FOK, Luxor, Egypt, Feb. 2018 5
Four major GM crops in the world
Michel FOK, Luxor, Egypt, Feb. 2018 6
Soybean
Corn
Cotton
Canola
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Herbicide tolerance accounts much more than insect resistance in commercial use
Michel FOK, Luxor, Egypt, Feb. 2018 7
Almost exclusively 2 types of GM varieties
Herbicide tolerance
Insect resistance
Very high economicimpacts are claimed
Michel FOK, Luxor, Egypt, Feb. 2018 8
Productivity
Production cost
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Positive environment impacts by the reduction of pesticide use
Michel FOK, Luxor, Egypt, Feb. 2018 9
The use of GM varieties sounds good
• At the level of a specific country
– Australia: A clear but particular case
• Information extracted from the presentation of Mr. Michael Murray, Cotton Australia, in Tashkent, October, 2017
Michel FOK, Luxor, Egypt, Feb. 2018 10
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Dramatic decrease of insecticide use and of the cost to control pests, Australia
Michel FOK, Luxor, Egypt, Feb. 2018 11
Huge reduction of the amount of insecticide active ingredients per ha, Australia
…but the insecticide active ingredients have also evolved a lot, beingeffective at a much lower amount
Michel FOK, Luxor, Egypt, Feb. 2018 12
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Sequence of genes used for herbicide tolerance and insect resistance, Australia
Michel FOK, Luxor, Egypt, Feb. 2018 13
Australia: Continuously ranking 1st in yield
Michel FOK, Luxor, Egypt, Feb. 2018 14
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Great decrease of insecticide sprays vs Bt targeted pests in USA
• Heliothine sprays
Leonard, 2010 (Cotton Beltwide conferences, New Orleans)Michel FOK, Luxor, Egypt, Feb. 2018 15
Decrease of chemical controls in China
• Number of insecticide sprays for CBW (grey points) and all insect pests (black points) on cotton
1990 1994 1998 2002 2006 2010
Lu, Y., Wu, K.et al. (2012). Widespread adoption of Bt cotton and insecticide decrease promotes biocontrol services. Nature, 487, 362–366.
Michel FOK, Luxor, Egypt, Feb. 2018 16
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Impacts on yield is variable between countries
• No direct yield impact from herbicide tolerance
• Yield impact from insect resistance is variable
– According to countries
• Yield increase is higher in developing countries wherechemical control was not optimal
– According to the period considered
• Yield might increase in the short term, but coulddecrease in the mid‐term
Michel FOK, Luxor, Egypt, Feb. 2018 17
Pressure reduction in all countries Bt effectiveness
• Bt targeted pest pressure – Documented in all countries using Bt varieties
– No (not yet?) or rare case of pest resistance to Bt toxins
• Exception = India (single Bt gene for a while)
Michel FOK, Luxor, Egypt, Feb. 2018 18
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Negative impacts observed
• Negative trend: need for more chemicalcontrols
– pests not targted by Bt toxins
– weeds resistant to glyphosate
Michel FOK, Luxor, Egypt, Feb. 2018 19
New ennemies have emerged in several major cotton countries
• Well documented: USA, China, India
Michel FOK, Luxor, Egypt, Feb. 2018 20
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A bug in using GM:Bugs, new threat in US cotton fields
…but alsoaphids, jassids…Michel FOK, Luxor, Egypt, Feb. 2018 21
India
Michel FOK, Luxor, Egypt, Feb. 2018 22
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Evolution of the number of glyphosate‐resistant species of weeds in th USA
Michel FOK, Luxor, Egypt, Feb. 2018 23
The increase of weed resistance to glyphosate is impressive worldwide
Michel FOK, Luxor, Egypt, Feb. 2018 24
In 2016: out of 40 resistantspeciesrecorded,
17 are found in the USA
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Ironically more herbicides are being used resistant weeds management
RoundUp + 2 others
3 others + surfactant
3 others + surfactant
3 others + surfactant
RoundUp + 2 others
RoundUp + 2 others
RoundUp + 6 distinct other herbicides
RoundUp Ready Plus (resistant weed management program of Monsanto)Recommendations for a location in Georgia State
Michel FOK, Luxor, Egypt, Feb. 2018 25
Special focus on China
• Number of insecticide sprays for CBW (grey points) and all insect pests (black points) on cotton
1990 1994 1998 2002 2006 2010
Lu, Y., Wu, K.et al. (2012). Widespread adoption of Bt cotton and insecticide decrease promotes biocontrol services. Nature, 487, 362–366.
Michel FOK, Luxor, Egypt, Feb. 2018 26
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Farmers perceived an increased infestation of pestsnot targeted by Bt‐cotton
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2006 0,0% 99,1% 12,3% 54,7%
2007 3,0% 82,3% 11,3% 62,1%
2008 11,5% 61,2% 10,3% 56,8%
2009 11,0% 59,3% 6,3% 73,0%
2010 30,0% 40,4% 21,0% 46,7%
2011 11,2% 46,9% 10,7% 58,6%
2012 11,3% 33,5% 6,5% 75,7%
Opinions according to infestation levels
Mirids Aphis g.
Annual urveys conducted in HebeiAnswers to the question about the evolution of pest infestations over the 5 last years
Michel FOK, Luxor, Egypt, Feb. 2018
Chinese farmers no longer happy with Bt cotton
Share of farms unhappy with Bt cotton
regarding effectiveness, % 56.9regarding profitability, % 76.0
Share of farmers finding that bollworm infestation has decreased 35,1lygus infestation has increased 46,9aphis infestation has increased 58,6
Wang & FokHebei province, China. Survey in 2011.
Among 262 farmers surveyed
Michel FOK, Luxor, Egypt, Feb. 2018 28
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Effect against pests not so much lasting
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Hebei province, Yellow River Valley, survey in 2011
Number of sprays 10.8Number of "chemical controls" 20.3vs bollworms 6.1vs mirids 2.8vs aphis 7.8vs red spider 2.7vs 3 main sucking pests 13.3vs other pests 0.9
Michel FOK, Luxor, Egypt, Feb. 2018
Effect against pests not so much lasting
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Early spray against aphidsHebei Province, 2006
Michel FOK, Luxor, Egypt, Feb. 2018
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Increased costs to control pests
31Michel FOK, Luxor, Egypt, Feb. 2018
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Effect geographically localized
Michel FOK, Luxor, Egypt, Feb. 2018
Cotton area share in 3 cotton production regions
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Lessons to retain
• 1. Effectiveness must be debated by considering short term and mid‐term effects
– Valid both for pest resistance and herbicide tolerance
– Short term: Good
– Mid term: much less good if not bad
Michel FOK, Luxor, Egypt, Feb. 2018 33
2. Global and a‐phased assessmentsare misguiding
• Assessment of GM use must be contextspecific
– According to country
– Depending on time
• …but not the case for most of the availableassessments
Michel FOK, Luxor, Egypt, Feb. 2018 34
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3. The use of GM must anticipatereaction from the cropping eco‐system
• GM use is an action on an eco‐system
• Action implies reaction– Stronger is the action, stronger is the reaction
• The effect reversal observed in mid‐term isindicative of the reaction of the eco‐system– Resulting from a generalized and continuous use of GM
• The use of GM must anticipate possible reaction by eco‐system
Michel FOK, Luxor, Egypt, Feb. 2018 35
4. Best use of GM is reasoned partial use
• Option opposed to general and continuoususe
• Partial use ?
– Combine the use of GM with non‐GM: co‐existence
– The balance of the combination could/shouldfluctuate over time
Michel FOK, Luxor, Egypt, Feb. 2018 36
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Thank you for your attention
Michel FOK, Luxor, Egypt, Feb. 2018 37