Monoculturing
Toxin Genes
Briefing paper on the
environmental and health
effects of Bt transgenic crops
G. V. Ramanjaneyulu
Sreedevi Lakshmi Kutty
Alliance for
Sustainable and
Holistic
Agriculture
Contents
What is Bt ? ............................................................................................................................................. 3
Bt toxins and Bt transgenics .................................................................................................................... 4
How safe are Bt toxins? ...................................................................................................................... 4
Genetically modified Bt crops ........................................................................................................... 4
Bt toxins and GE Bt plants: Are they same? ............................................................................................ 5
Bt proteins from natural Bt sprays degrade relatively quickly in the field as a result of ultraviolet light
and lose most toxic activity within several days to two weeks after applicationvii. In Bt crops,
however, the Bt toxin is produced throughout the entire lifespan of the plants. .................................. 6
Health concerns with Bt transgenic crops............................................................................................... 7
EPA (2002) Regulation of Bacillus thuringiensis (Bt) Crops ................................................ 15
What is Bt ?
Bacillus Thuringiensis is a naturally occurring gram positive, spore-forming soil bacterium which
has been found to be toxic for certain insect species. When resources are limited, the vegetative
Bt cells undergo sporulation, synthesizing a protein crystal during spore formation. Proteins in
these crystals are called Cry (from Crystal) endotoxins and have been known for decades to
display insecticidal activity against specific insect groups. It was
first isolated in Japan in 1901 and identified and named in 1915 and
was first made commercially available in 1938 in France and has
been in extensive use as a bio pesticide since 1958 (IFS, 1994,
Hilbeck, 2007). It is the most important microbial pesticide being
used in the 20th century. The Bt toxin consists of proteins which
are classified into four major classes, Lepidoptera specific (I).
Lepidoptera- and Diptera-specific (II), Coleoptera-specific (III), aind
Dipteral-specific (IV) toxins Between these they are extensively
used for controlling important pests in agriculture and forestry. It is most commonly used
against insects of the Lepidoptera class and in spray form.
The commonly accepted method of action of Bt toxin is by binding itself to the receptors in the
gut lining of the target pests. Then the target insect dies of starvation, septicemia and bacterial
growth in its gut (Hilbeck, 2007). Bt sprays are the most commonly used form of pesticides, due
to its perceived environmental safety and the presumed specificity of its toxins, however many
studies have revealed problems with Bt use on beneficial and non target insects, some these are
wasps, aphid eating flies, certain caterpillars species, aquatic insects and certain birds (IFS,
1994).
Source: http://web.utk.edu/~jurat/Btresearchtable.html
Bt toxins and Bt transgenics
How safe are Bt toxins?
Despite the fact that the manufacturers of Bt sprays claim it to be benign to human beings it has
not been found to be so from the health problems reported from various countries. There have
been few studies about toxicity of Bt however there are many reports of problems due to
occupational exposure causing irritation to the eyes and skin (Swadener, 1994).
In New Zealand a people’s tribunal was held in 2006 post numerous problems experiences due
to the aerial spraying of Foray 48B (whose active ingredient is Bacillus thuringiensis var kurstaki
or called delta endotoxin or Bt toxin.) in 2002 over urban areas in Auckland to destroy painted
apple moths, a minor migrant pest of pine and apple trees (Peoples Enquiry, 2007) People
reported eye, nose, throat and respiratory irritation which coincided with the frequency of the
sprays. When natural Bt was sprayed over Vancouver and Washington State to deal with gypsy
moths, many people reported allergy symptoms and a few had to go to the emergency room
(Green 1990). Monitoring studies done after Bt sprays have established that people carry Bt in
their tissues after being exposed to it and many of the exposed people had to be treated for
allergy and flu-like symptoms (Swadener, 1994).
Genetically modified Bt crops
Due to the popularity of these pesticide properties of Bt scientists tried to produce them in the
plants by incorporating genes from the bacteria into the plants. It assumed that by doing so the
genes perform a similar function of producing the same toxin in the plant safeguarding them
against certain insect pests. This is done using a gene gun or through Agrobacterium tumefaciens
as the vector for carrying the desired genes. The resultant plant can synthesis its own toxins to
kill the pests. Initially plants were engineered with the Cry1Ab or Cry1Ac genes and increasingly
plants are being engineered with two or more Bt genes.
Genetic engineering is an imprecise, unpredictable and irreversible technology and the Bt plants
created using these could have many unintended effects. The Bt toxin produced in the transgenic
plants is a more active form than the naturally occurring Bt toxin used in pesticides (Hilbeck,
2001) and could be more dangerous to a larger variety of life forms. GM crop promoters call
transgenic plants engineered with Bt toxin and insect-resistant plants however they are
insecticide generating plants.
As Dougherty and Parks (1995) writes, "Organisms that do not perform as expected are
discounted as defective or atypical in some way, are not the subject of study, and frequently are
not reported in the literature. It is important, therefore, to recognize that most published works
represent a selected subset of transgenic organisms that have been produced. These built-in
biases have hindered our understanding of how transgene expression impacts the endogenous
[host] gene"
In an article in the June 2011 issue of the Journal of Biosciences, ‘Detrimental effect
of expression of Bt endotoxin Cry1Ac on in vitro regeneration in vivo growth and
development of tobacco and cotton transgenics,' Delhi University scientists reported
that the expression of the Cry1Ac endotoxin has detrimental effects on the
development of transgenic plants. The plants that showed appreciable CryIAc
expression were phenotypically abnormal: they were malformed. This suggests
preferential selection is at work while transgenic plants mature: those that express
low level of Cry1Ac have better chances of coming through compared with ones
expressing appreciable levels of the gene. The reason for the detrimental effects of
Cry1Ac on plant growth and development is not known and understanding it would
require further investigation. However, the finding gives leads to understanding
several problems about Bt genes. Phenotypical abnormality in plants with high levels
of CryIAc expression could be a result of a metabolic aberration during the process of
gene transfer or gene itself. In addition to physical abnormality, such metabolic
abnormality can also cause allergies and produce toxins detrimental to non-target
organisms like friendly insects, soil microbes, cattle or other mammals including
humans feeding on the plants or its products. Earlier reports on toxicity to monarch
butterflies, reduced soil fertility and the controversial phenomenon of animal
morbidity/mortality could be explained if there is further research along these lines
(Rawat et.al 2011)
The authors suggest that targeting of Cry1Ac into chloroplasts rather than nuclei can
lead to plants expressing higher levels of Cry1Ac and better insect resistance.
However, the finding that expression of a Bt-toxin per se is detrimental to plants is
significant since the toxin was earlier thought to harm only certain insects. The
findings reveal large knowledge gaps as well as actual problems associated with Bt
transgenic crops. An immediate ban needs to be imposed on all crops using Bt genes
till further research shows that the technology can be precise, predictable and
controllable in addition to being safe.
The first genetically engineered Bt crop was approved for commercial cultivation in the US and
interestingly these crops were registered and classified as pesticides by the Environmental
Protection Agency(EPA) and therefore studied and evaluated for that and not as plants which
have been engineered with the toxin to produce them from every living cell (EPA, 2002). In 1995
EPA registered the first transgenic Bt plant which it calls “Bt plant-incorporated protectant”. For
many years EPA’s approach to GE plants with BT toxins has been a product based approach
thereby not taking into account the process by which it has been created.
Substantial Equivalence: Are Bt toxins and GE Bt plants the same?
In the natural Bt sprays the bacterial "pro-toxin" is in an inactived state and only becomes toxic
when processed in the gut of certain (targeted) species of insect larvae. In contrast, many insect
resistant plants contain an artificial, truncated Bt gene and less processing is required to
generate the toxin. It is therefore less selective, and may harm non-target insects that do not
have the enzymes to process the pro-toxin, as well as the pests for which it is intended (Fig. 1)
Fig. 1 Differences between Bt-insecticides and GE Bt-plants
Bt proteins from natural Bt sprays degrade relatively quickly in the field as a result of ultraviolet
light and lose most toxic activity within several days to two weeks after applicationvii. In Bt
crops, however, the Bt toxin is produced throughout the entire lifespan of the plants.
These transgenic plants have been subjected to only short term studies for acute toxicity by the
GM crop developers and no long term studies to measure the impact chronic toxicity have been
carried out. Another factor that is ignore is the fact that today the level of exposure to Bt toxin of
a human being is much higher than it has been ever before (and in the active form), but there is a
significant lack of research to analyze Bt toxins as toxin or allergens in the “context and
concentration” that humans are exposed to it (Heinemann, 2009).
The GM crop developers claim that Bt plants are beneficial as they provide season long pest
control with the plant generates its own toxin and allows reduced use of broad spectrum
pesticides. However the assumption that Bt crops are the same as Bt sprays is incorrect, they are
different in their composition and impact. Bt sprays persist on the surface of the plant for
sometime after a spray operation however the Bt crop actively expresses the toxin throughout
the plant’s life. The Bt sprays contain inactive protoxins, spores and bacterial cells that have to
be activated through a complex process whereas the transgenic Bt plants contains the Bt toxin in
an activated form (Hilbeck & Schmidt, 2006).
Concerns with stability of Bt transgenicss
Health concerns with Bt transgenic crops
Already Bt sprays are known to generate allergic reactions in human beings. In addition now Bt
toxins are being engineered into plants and human beings are exposed to it through. According
to Jack Heinnemann, there are two reasons to examine the effect of engineered Bt genes as (1)
there is change in the interface between engineered Cry genes and other bacteria and (2) there
has been increased exposure of human beings to Bt (Heinnemann, 2009).
DNA traces in animal tissues
A survey of recent scientific literature by test biotech revealed that numerous instances and
studies have established that DNA fragments from GE plants are being found in animal tissues,
for example in milk, muscles and organs. With mice it has been known for years that transgenic
DNA do not decompose in the stomach and could be found in other organs. The DNA traces were
identified in animals ranging from goats to pigs to fishes and this is contrary to the belief held by
many scientists and EFSA that recombinant DNA could not be detected in animals (Tudisco,
2010).
Bt cotton and animal morbidity
Since 2005 there have been reports of illness, and in some cases death of cattle which foraged on
bt cotton leaves and bolls from the standing crops by Centre for Sustainable Agriculture and
ANTHRA reported from Andhra Pradesh (CSA, 2006). ANTHRA ‘s study on this matter has
shown that usually the third day after consumption of Bt cotton foliage/cake etc the animals
show signs of nasal discharge, cough, respiratory distress and sometimes bloody urine. In
Haryana cows fed on Bt cotton seed cake had lower milk yield (Ramdas, 2010). In a letter to
GEAC, the Director, Department of Animal Husbandry, Government of Andhra Pradesh in 2007
wrote that ‘animal deaths were observed after feeding on Bt cotton in February-March, 2006
and 2007 and in discussions with crop developers and scientists it was felt that the biosafety
tests done were inadequate to establish the safety of Bt cotton to animals (Department of Animal
Husbandry, 2007).
Mice fed with transgenic corn with Cry1Ac protoxin showed “systemic and mucosal” responses
similar to those generated by the Cholera toxin. The study further demonstrated that Cry1Ac
protoxin binds to the surface of the mouse’s small intestine (Vazquez-Padron et.al, 2000).
Another study done on mice by the same scientists demonstrated that Cry1Ac protoxin is a
“potent immunogen able to induce a specific immune response in the mucosal tissue, which has
not been observed in response to most other proteins” (Vazquez-Padron, 2000b).
GM corn and Organ Damage
A study published in the International Journal of Biological Sciences demonstrates the toxicity of
three genetically modified corn varieties (MON810, MON863 and NK603) from Monsanto. The
three corn varieties are engineered for tolerance to herbicide Roundup. MON 810 and MON 863
also had stacked Bt genes for insect resistance. In their analysis researchers from Criigen could
clearly link consumption of this corn to organ damage in mammals. Organs from the kidney to
liver and many others were observed to be effected. Dr.Seralini said that their conclusions
differed from that of Monsanto as they have gone beyond the 90 day studies that Monsanto has
done, which is hardly sufficient to detect effects of chronic toxicity and also explored “sex
differentiated health effects on mammals” (de Vendomois et.al 2009).
Persistence of Bt toxins
One of the argument scientists and industry has put forth is the Bt toxins are active only in
alkaline medium atA study conducted in Quebec, Canada, by doctors in the University of
Sherbrook hospital , with pregnant and non pregnant women who are exposed to Bt toxin
Cry1Ab through genetically engineered food. Bt toxin was detected in 93 % of the maternal
blood samples and 80% of the fetal blood samples and in 69% of the blood samples of the nonpregnant women. According to the conclusions of the study the Bt toxin appears to cross from
the placenta to the fetus (Aris et.al, 2011).
Environmental Effects
Effect on non target organisms: One of the advantages cited by GE scientists about Bt is that it
is benign toward non target organisms. However many studies have questioned this assumption
and numerous instances of the toxic effect of the transgenic Bt plant on non target organisms
have been found.
One of the earliest reported studies on the impact of genetically engineered Bt plants was that of
Monarch butterfly deaths due to feeding on leaves dusted with Bt corn pollen. Since then
research has established that honey bees, a major pollinator and one of the most beneficial
organisms, are negatively affected by foraging on Bt plants which carry the Cry1Ab endotoxin.
The bees exposed to the transgenic Bt plants demonstrated disturbed development and learning
performance and their feeding behavior was also effected, thereby creating the possibility of
impacting their foraging efficiency (Ramirez et al, 2007).
Impact on Water bodies and aquatic life forms: A study published in the journal “Proceedings
of the National Academy of Science Researchers has established that the insecticide in Bt corn
polluting rivers and water bodies in the US. They have found that the insecticide from the Bt
corn has leeched into many streams and rivers studied. Researchers as yet do not yet know what
impact this has on the aquatic biology of the water bodies”(Rosi-Marshall et.al, 2007)
A study by Bohn et al to check the effect of transgenic Bt maize with Cry1Ab endotoxin on
Daphnea magna , a crustacean arthropod( commonly used as model organism for ecotoxicology
testing) found that when these are fed with ground Bt maize leaves they showed reduced fitness,
higher mortality, reduced egg production in females and a lower number of females reaching
maturity (Bohn et al, 2008). This demonstrates that in addition to affecting non target terrestrial
life forms Bt toxins can affect aquatic systems, containing numerous non target organisms,
which receive run off material from BT fields. A study in 2007 concluded that in Midwestern
United States where Bt Corn with Cry1Ab toxin is widely planted corn plant parts enter
headwater streams and are consumed by non target stream insects causing reduced growth and
increased mortality (Rosi-Marshall et all, 2007)
Effect on soil microorganisms: The effect of the large amount of active Bt toxins generated by
the transgenic plants and their impacts on the soil systems show that the soil in which Bt cotton
grew has lower average soil respiration rate (an important index to asses biological activity of
the soil), lower level of activity by a section of soil microbes and a negative effect on availability
of mineral nitrogen in the soils (Sarkar et al, 2008).
Studies with two transgenic BT corn lines (Bt 11 & Bt 176) expressing Cry1Ab protein
demonstrated that they have a significant impact on arbuscular mycorrhizal (AM) fungi, an
important component determining soil fertility, plant nutrition and . AM fungi are an important
non target soil organism due to its significant role in sustainable agriculture. Both the Bt plants
resulted in decreased root colonization activity by the AM fungi (Turrini, A et al, 2008).
Bt Crops and Resistant Development
Weather the weapons are pesticides sprayed on to the crops or genetic protection built into the
plant, the pest usually adapts to the new conditions sooner or later and the protection becomes
ineffective. Transgenic Bt cotton plants contain genes for Bt toxins derived from the soil
bacterium Bacillus thuringiensis. These toxins kill the caterpillar stage of bollworms; Helicoverpa
armigera (Cotton bollworm) and Pectinophora gossypiella (Pink bollworm). Although no
instance of bollworm resistance to Bt cotton in the field has yet been reported, bollworms are
known to be able to develop genetic resistance to Bt toxins as per the reports from researches in
USA, Australia and India. To prevent or delay the emergence of insect resistance to Bt crops, the
biotechnology industry and the Environmental Protection Agency developed a Insect Resistant
Management (IRM) strategy as a component of seed contracts biotechnology companies sign
with farmers.
Due to the threat of development of resistance within target species due to the constant
exposure to the active form of the toxin, EPA has mandated that transgenic plants Insect
Resistance Management plan which involves with Bt be grown with refugia of non transgenic
plants. This has been mandated with the expectation that insects which have developed
resistance to the Bt toxin will breed with those which have not developed resistance and thereby
dilute the toxicity. However in the Indian context it has been found that farmers are rarely
adhering to the refugia strategy.
The company suggested IRM strategy during release of Bt cotton in US operates on a high dose
and refuge strategy.
a. The high-dose component of the IRM strategy dictates that the dose of the toxin would
several folds than sufficient to kill all target insect pests.
It assumed that at this level no insect will escape the poison there leaving no room for the
question of resistance insects surviving. However the toxin expression in the plants depends on
environment and can vary from plant to plant, between different parts of the plant and within
the same plant part over time.
b. The second component of the IRM strategy is the use of refuges of non-Bt crops.
Refuge: which aims at creating a barrier for mating between resistant insects which survive on
the Bt crops. Among the insects feeding on bt cotton susceptible ones die and only resistant
ones survive. They mate among themselves and increase their numbers. Hence, a refuge
strategy where certain area is marked for non-Bt crop which is managed without using
pesticides is suggested.
Resistant insects
Resistant insects
Susceptible insects
The success of this strategy depends on the fact that resistance to Bt has been found to be a
recessive trait. That means that Bt will still be effective against an insect that carries both a Btresistant gene and a Bt-susceptible gene because the susceptible gene dominates. Refuges allow
Bt-susceptible insects to proliferate without selection pressure from Bt toxins. The susceptible
insects are then available to mate with resistant insects that may emerge from the Bt field. This
slows the spread of the recessive gene and lowers the chance that succeeding offspring carrying
two Bt resistant genes will proliferate.
However in practice this seems to have been not working.
Resistance Management by the High-dose/ Refuge-the Global Experience:
The EPA and most industrial companies clearly pursue the high dose/refuge approach. A 4-5 %
refuge without insecticide use or about 20-25 % with insecticide spraying were demanded by
the EPA for the cotton and corn varieties (See EPA website http://www.epa.gov). The high dose
concept combined with refuge provisions in the USA is not accepted as a best practice by some
Entomologists (Ferro 1993, Mc Gaughey and Whalon 1992, Shelton et al.1993, Melon & Rissler
1998). Gould et al (1997) predicted a 10 year period without resistance problems concerning
Heliothes virescens and only a 3 year period for the bollworm complex (Pectinophora gossypiellapink bollworm, Helicoverpa zea-cotton bollworm or Helicoverpa sp.) taking into account a
portion of 4% refuge without insecticide use in cotton. These predictions have been based on
monitoring the frequency of resistance alleles in the USA. Although computer simulations and
population genetic theory, laboratory and green house tests support this high dose/ refuge
concept, there are serious reasons not to rely on it. The models, simulations or green house tests
do not take into account a wide range of environmental irregularities. Temporary, very high pest
pressure due to regional climate differences, the occurrence of dominant resistance alleles in
some populations, long range flights of resistant genotypes or varying expression levels due to
different promoters, silencing or plant age can undermine the concept in nature.
The concept is valid when 99% of the individuals (by transgenic varieties) and 100% of the
resistant heterozygotes are killed. Therefore, the toxin expression must be uniform in time and
space. The more target insects that are included in the control Bt transgenic variety the more
difficult are the assumptions for the refuges to meet. The refuges should be as large as they need
to be in order to prevent feeding instars from moving to non-Bt plants and small enough to make
many individuals mate in the refuge (Mallet &Porter 1992, Tabashnik 1994, Gould & Tabashnik
1998).
Studies on Resistance to Bt in India:
A study by Fakruddin et al (2002) of Dept. of Biotchnology, UAS, Dharwad and Dept. of
Entomology, Collage of Agriculture, Raichur revealed the resistance of H.armigera to Cry1Ac
toxin in 11 distinct geographic populations representing the entire South Indian Cotton
Ecosystem. The data shows that even before the use of Cry1Ac transgenics, the level of
resistance was 8.4 fold in Nanded population followed by 8.03, 7.70, 7.13, 6.80, respectively for
Guntur, Nalgonda, Madhira and Raichur. Notably, variability for response to Cry1Ac toxin does
exit in the target population, whether or not previously exposed to the toxin. When the Bt cotton
was permitted for commercial cultivation in India, Genetic Engineering Approval Committee
(GEAC)
has
imposed
similar
restriction
in
terms
of
growing
refugia
(http://envfor.nic.in/divisions/csurv/btcotton/bgnote.pdf). But, the conditions were put
without any basic studies. For example the refuge strategy should be developed only after
considering
1. the recessive/dominance factor of resistance
2. the initial frequency of the resistant allele
3. the mating behavior of the insect moth
and differential plans based on whether refuge crop is sprayed or unsprayed was never
mentioned. GEAC has just borrowed the recommendations from the EPA without any studies
being done in India on refuge requirements. The company also, while clearly mentions the
strategy in US, in India has not advised its farmers not to spray on the refuge. At all the places
farmers are seen using pesticides as regularly. The Monitoring and Evaluation Committee
reports clearly showed that refuge is not planted in most parts of the country. The company
argued that other non bt cotton and other crops which acts as hosts for Helicoverpa acts as
refuge and allow them to dispense with refuge requirement.
Kranthi et.al, 2005 reported that the quantitative levels of Cry1Ac and the seasonal decline in
expression differed significantly among the eight commercial Bollgard hybrids tested. The
Cry1Ac expression was found to be variable among the hybrids and also between different plant
parts. The leaves of Bt-cotton plants were found to have the highest levels of Cry1Ac expression
followed by squares, bolls and flowers. The toxin expression in the boll-rind, square bud and
ovary of flowers was clearly inadequate to confer full protection to the fruiting parts. Increasing
levels of Helicoverpa armigera survival were correlated with the toxin levels decreasing below
1.8 mg/g in the plant parts. Genotype-independent seasonal decline of the Cry1Ac toxin levels
was observed in all the hybrids. Cry1Ac expression decreased consistently as the plant aged. The
decline in Cry1Ac was more rapid in some hybrids compared to others.
Pest resistance to Bt cotton: The primary purpose, cited by the biotechnology industry, for
creating Bt crops is to reduce the use of pesticides, however Bt crops have within a short period
seen development of resistance amongst the target insect population which has resulted in the
unenviable situation of planting toxin generating and spraying pesticides on them. Another
problem is that the disturbance of the pest ecology by these crops has resulted in the emergence
of many secondary and minor pests into major threats to the cropping system.
Resistance strategy advocated by the GE promoters and the EPA has been a combination of high
dosage of toxin and refuge . However many entomologists are against this strategy as this
strategy despite good results in the labs has not been effective on the fields. Experiments and
studies have shown that the development time of bollworm larvae feeding on Bt cotton is take 56 days longer than larvae not exposed to Bt cotton and therefore despite refugia it is very likely
that two resistant bollworm moths would mate with each other . Even under laboratory
conditions resistance developed within 5 years and in the field with much larger populations it
will take less time that that ( Ramanjaneyalu, 2010)
Resistance to Pink Bollworm
In March 2010 Monsanto India admitted in a press release that Bollgard1, the Bt cotton with the
single protein Cry1Ac, has developed resistance to pink bollworm(Pectinophora gossypiella)1 2.
Resistance was confirmed in four districts in Gujarat - Amreli, Bhavnagar, Junagarh and
Rajkot.They advised farmers to adopt Bollgard II their own Bt cotton with stacked genes. Pink
Bollworm being specific to cotton, mono cropping of bt cotton has led to fast resistance
development). However Monsanto blamed farmers for not adopting refuge and spurious bt
cotton hybrids grown in Gujarat3.)
Implications to Bt Brinjal: Neither the company and CICR which were supposed to have
reported this every year nor the GEAC which was supposed to have reviewed the reports have
admitted this problem during Bt Brinjal consultations which is clearly amounts to withholding of
information. Brinjal Fruit and Shoot borer is also a monophagus pest like Pink Bollworm. Hence
similar resistance development would be seen.
Resistance to Bollworm
A study done in Karnataka by scientists from the University of Agricultural Sciences in Raichur
and the Institute of Wood Sciences and Technology in Bangalore (Ranjith et.al 2010) has
established that the bollworm the major cotton pest in India is not only thriving on both the
single gene Bt cotton( Cry1Ac) and the double gene Bt cotton (Cry1Ac & Cry2Ab). The authors
said that it has been demonstrated that the bollworms not only survive after feeding on Bt
cotton plants, they are able to complete their lifecycle and reproduce and create the next
generation of resistant pests.
The double gene Bt cotton was introduced in India just four years back in 2006 while the single
gene product, which has already shown resistance to pink bollworm, was approved in 2002. In
2008 when it was reported in a study by Bruce Tabashnik (Tabashink, 2010)in the US that Bt
cotton had developed resistance to bollworm (Helicoverpa zea), officials of Mahyco Monsanto
1
http://indiatoday.intoday.in/site/Story/86939/India/Bt+cotton+has+failed+admits+Monsanto.html
http://www.business-standard.com/india/news/setback-for-bt-cotton-main-pest-developsresistance/387703/
2
3
(http://www.monsanto.com/monsanto_today/for_the_record/india_pink_bollworm.asp
Biotech Ltd were quick to reassure that the key target pest to cotton in India had a different
resistance pattern and that in addition Bollgard II was “a superior” product .4
The resistance development in bollgard also has an implication on other varieties and hybrids
being developed by public sector institutions. The first public sector variety (Bikeneri Narma bt)
and hybrid (NH-44 Bt) both with Cry1Ac were released in 2008 year and began cultivation only
this year. If insects develops resistance to this toxin what would be the status of the farmers
who uses it? As this technology lag between public sector and private sector always happen,
their research will not be irrelevant most of the times.
Emergence of minor pests into major pests: Dr. Keshav Kranthi of Central Institute for Cotton
Research has said that due to the widespread adoption of Bt cotton secondary pests like mealy
bugs and whiteflies have emerged as a major problem in Bt cotton forcing farmers to spray toxic
chemicals and pesticide usage in Bt cotton is on the rise after an initial decline 5 6 7. He said that
almost 90% of the Bt cotton hybrid grown in India is susceptible to these two pests and reported
that insecticide use in cotton increased from Rs 640 crores in 2006 to 800 crores in 2008.
A ten year study, across 1997-2008, in China revealed that Bt cotton cultivation has resulted in a
12 fold increase in mirid bugs, formerly a minor pest in cotton, making it the major pest of Bt
cotton and inducing farmers to spray pesticides extensively. This jump in mirid bug population
is also affecting other crops in addition to reducing cotton yields as much bollworm did in the
pre Bt days (Wu et al, 2010).
What we have with transgenic crops is a succession of short term, sort of silver bullet
solutions…providing false hope to many people that transgenic crops are going to solve the
problems of pest control.
Exorbitant seed prices and loss of farmer control
Since the introduction of Bt cotton in India, on one hand we have had unabated farmer suicides
in the cotton belt8 and on the other, the exorbitant royalty earned by Monsanto between 2002 –
2008 is Rs 1530 crores, that too without a registered patent on the product in India (the Bt
patent was not been valid in India till 2008)9 . The situation was so bad that the Andhra Pradesh
government went to the Monopolies and Restrictive Trade Practices Commission (MRTP) in
http://www.financialexpress.com/news/no-signs-of-bollworm-resistance-to-bt-cotton-in-indiamahyco-monsanto/276655/0
5
Cotton lessons for Bt brinjal, Telegraph India,
http://www.telegraphindia.com/1100216/jsp/nation/story_12110833.jsp
6
Some Bt cotton pests on the rice, Live Mint, http://www.livemint.com/2010/05/13232824/Some-Btcotton-pests-on-the-ri.html
7
Bt cotton : A critical appraisal, K.R.Kranthi, Annexure to Bt brinjal decision note, Ministry of
Environment and Forests, page 180-190, http://moef.nic.in/downloads/publicinformation/Annex_BT.pdf
8
9
http://www.counterpunch.org/sainath02122009.html
http://www.business-standard.com/india/news/latha-jishnu-an-odd-royalty-calculus/399194/
2006 to challenge the horrendous price of Rs 1800 for 450 gms of seed out of which Monsanto
was being paid a technology fees of Rs 1200 .
In the last 7 years since the introduction of Bt cotton conventional cotton varieties have
disappeared from the Indian seed market and are not available for the farmers if they want to
plant it. Neither the private seed dealers nor the public sector produces or sells conventional
cotton seeds, thereby forcing farmers to buy Bt cotton, which has been engineered into hybrid
varieties that have to be replaced every year.10 In addition contamination of parental lines of
cotton varieties by Bt cotton has taken place. Contamination happens due to lack of isolation
distance and thereby cross fertilization, mixing up of Bt cotton and non Bt cotton during ginning
process etc.11
Alternatives to Bt crops
Pest management through NPM: The biotechnology industry has been selling Bt as an antidote
to pesticide usage claiming that using genetically engineered Bt crops will reduce use of
pesticides. However according to reports by Dr.Keshav Kranti, from CICR after initial reduction
in pesticide usage in Bt cotton, there has been an upsurge in pesticide usage for Bt crops (
cotton) to deal with emergence of secondary pests. This has happened within five years of
introduction of Bt cotton in India clearly demonstrating the very short term effect of genetically
engineered Bt crop.
On the other hand organic farmers around the country have established that all crops can be
grown successfully without pesticides . In addition a large successful ongoing non pesticide
management program in Andhra Pradesh has established beyond doubt that the BT technology
is definitely not required to reduce pesticide usage.
The Minister for Environment & Forests Mr. Jairam Ramesh, in the BT brinjal decision document,
talked about the experience of Non Pesticide Management (NPM) agriculture being practiced in
Andhra Pradesh, as an economically and ecologically sound way to deal with the issue of heavy
use of pesticides12. He pointed out that while Bt reduced pesticide usage , NPM eliminated the
need for pesticides.
The seeds of the Community Managed Sustainable Agriculture (CMSA) project were sown with
the work by Centre for Sustainable Agriculture (CSA)13 on non pesticide management
agriculture in Andhra Pradesh, a state with very high levels of pesticide usage.
The beginning was in Punukula village in 2001 with 200 farmers, which became pesticide free in
200314, without loss of yield and with good profits for farmers. Enabhavi village went another
step ahead and became completely organic. This was while the state was experiencing high
levels of farmer suicides due to indebtedness15 . Seeing the success of this model Society for
Elimination of Rural Poverty(SERP)16 , a unit of the state governments rural dept , joined hands
10
Every 30 minutes farmer suicides, human rights and the agrarian crisis in India,
http://www.chrgj.org/publications/docs/every30min.pdf
11
Contaminated cotton, Kavita Kurungati, Ramanjaneyalu & Jayaram ,
http://www.grain.org/research_files/cotton_contaminated.pdf
12
Decision on commercialization of Bt brinjal, Ministry of Environment and Forests,
http://moef.nic.in/downloads/public-information/minister_REPORT.pdf
13
CSA was then called Centre for World Solidarity
Managing pests without pesticides, http://www.engagingcommunities2005.org/abstracts/Ramanjaneyulufinal.pdf
15
ibid
16
SERP was set up by the rural development dept of the Andhra Pradesh state government
14
with CSA in 2004 to take this forward as a full fledged program across 400 acres of land in 12
villages involving local women’s self help groups (Vijay Kumar T et.al 2010).
CMSA is based on a judicious combination of scientific methods, indigenous practices and
traditional wisdom. With integrated pest management as its pivot CMSA advocates : managing
pest populations through understanding pest behavior, improving soil health, increasing
diversity of crop systems and using local land races , replacing chemical pesticides with physical
methods and bio pesticides and reducing ( and eventually stopping) the use of synthetic
fertilizers 17. CMSA has been ably managed by robust community institutions and able
leadership within the community; farmers are mobilized into self help groups, trained through
farmer field schools and provided institutional support for credit and value addition. Currently a
million farmers are practicing non pesticidal management across an area of 2.5 million acres (1
million ha) spread over 7000 villages in 22 districts of Andhra Pradesh (Dr.Ramanjaneyalu,
Exe.Director, CSA).
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