C Kameswara Rao

Foundation for Biotechnology Awareness and Education

Bangalore , India



In the year 2008, about 30 countries have approved genetically engineered (GE) crops either for commercial cultivation or for imports.  Global cultivation of GE crops increased from 1.7 mill ha in 1996 to 125 mill ha in 2008, accounting for a cumulative acreage of two billion acres (800 mill ha) (James, 2008).  Issues related to the impressive growth of GE crops and the diverse benefits of 13 years of their commercialization are in detailed by James (2008).


Transgenic technology, involving a wide range of pesticidal genes from the universally occurring soil bacterium Bacillus thuringiensis (Bt), dominates the scenario of GE crops (the Bt crops).  Literature on Bt, discovered over a 100 years ago and in use as a pesticide for some 70 years, is very vast.  The reader is advised to refer to ‘Transgenic Bt technology’ (Kameswara Rao, 2009), for a referenced review of the technology and related issues.

Bt proteins are per se not toxic. To function as toxins Bt proteins require a specific set of biochemical and biological parameters which are available for different Bt proteins only in specific insect groups, which makes Bt toxins insect group specific. For example, Cry1Ac and Cry2Ab control the cotton bollworm, Cry1Ab controls corn borer, Cry3Ab controls Colorado beetle of potato and Cry3Bb controls corn rootworm. The Bt genes incorporated into different crops are specific to Lepidopteron (having wings covered by scales) pests on them (Glare and O’Callahan, 2000).

The following Bt crops are in commercial cultivation or permitted for imports in different countries (James, 2008):

Bt corn: Argentina, Australia, Brazil, Canada, Chile, China, Columbia, Czech Republic, Egypt, European Union Countries, Honduras, Japan, Mexico, Netherlands, New Zealand, Philippines, Romania, Russian Federation, Singapore, South Africa, South Korea, Switzerland, Taiwan, UK, Uruguay and USA.

Bt cotton: Argentina, Australia, Brazil, Burkina Faso, Canada, China, Columbia, European Union Countries, India, Indonesia, Japan, Mexico, New Zealand, Philippines, South Africa, South Korea and USA.

Bt potato: Australia, Canada, Japan, Mexico, New Zealand, Philippines, Russian Federation, South Korea and USA.

Bt tomato: Canada and USA.

Bt rice: Iran and China?

Several other Bt crops are in different stages of development in different countries. 


While there are about 80 GE traits of some 30 crops are in various stages of development, only Bt cotton and Bt brinjal currently occupy the centre stage in India.

3.1 Bt Cotton

In India, Bt cotton containing the Bt geneCry1Ac is the only commercialized GE crop, whose cultivation increased from 0.5 mill ha in 2002 to 7.6 mill ha in 2008 (James, 2008), which indicates that the Indian farmers have in fact accepted the technology for the benefits that accrued.  In the period from 2002 to 2008, Indian Bt cotton scenario changed rapidly in terms of the number of Bt farmers, approved hybrids (three to about 160), transgenic events (one to five) and seed companies (one to over 30). During this period, farmer profits increased between 50 to 110 per cent with yield increase between 30 to 60 per cent and a reduction of over 50 per cent in pesticide usage, benefitting about five million resource poor farmers (James, 2008). 

Wu et al., (2008) observed that Bt cotton suppressed bollworm in the neighbouring non-Bt crops in China.

3.2 Bt Brinjal

Brinjal (aubergine, eggplant) is cultivated throughout the world (Daunay, et al., 2001a).  In India alone, 25 million farmers cultivate brinjal on over 5.5 lakh hectares with an annual production of about 8.5 million tonnes (Choudhary and Gaur, 2009).

Since the year 2000, Maharashtra Hybrid Seed Company (Mahyco) has been developing Bt brinjal hybrids, the GE Event EE-1 containing the Bt gene Cry1Ac, while the Tamil Nadu Agricultural University, Coimbatore (TNAU) and the University of Agricultural Sciences, Dharwad (UASD) have developed Bt brinjal varieties, which give the farmer the choice of recycling the seed in the following season, unlike the hybrids.  The Indian Agricultural Research Institute (IARI) has been developing a Bt brinjal with Cry1Ab gene. 

The objective of developing Bt brinjal hybrids and varieties is to control the damage caused by the stem and fruit borers (SFB) of brinjal.   Shoot damage severely restricts flower and fruit production and fruit damage drastically reduces marketability of the produce.  Even after continuous and very heavy insecticide application, the SFBs affect 50 to 70 per cent of the crop yield annually, the damage starting from the nursery and carried to the next crop (Choudhary and Gaur, 2009).  External application of insecticides does not much help as the pest is deep in the stem and fruit tissues.  The Cry1Ac gene imparts an inbuilt systemic tolerance to the pests, particularly Leucinodes orbonalis.   Helicoverpa armigera (American bollworm),the major pest on cotton which is controlled by Cry1Ac gene, also affects brinjal fruit.  The Bt brinjal effectively resists both these pests resulting in diverse benefits to the farmer, consumer and the country, more particularly vastly enhanced produce recovery and the avoidable use and exposure to pesticides and their residues.

Mahyco has integrated EE1 into eight of its own brinjal hybrids (MHB 4, 9, 10, 80, 99, 11, 39, 111). The TNAU developed Bt brinjal varieties Co-1, PLR-1, MDU-1 and KKM-1, while the UASD developed Bt varieties Manjari Gota, Udupi Gulla, Malapur local, Kudachi local, 112-GO hybrids and Rabkavi local, together covering a large part of the needs of the different States, though several more Bt hybrids and varieties need to be developed to every suit the requirements of every brinjal growing region in India.   

3.3 Private-Public Partnership

The development of Bt brinjal varieties constitutes a welcome private-public partnership.  A similar arrangement is extended to the Indian Institute of Vegetable Research, Varanasi, University of Philippines, Los Banos, Bangladesh Agricultural Research Institute and a private seed company, East West Seeds, Bangladesh. The transfer of technology from the private to the public sector was effected through the Agricultural Biotechnology Support Project II, funded by the USAID and managed by the Cornell University. 


4.1 Biosecurity

In the context of modern agricultural biotechnology the term Biosecurity has two components: a) Biosafety, the safety of genetically engineered (GE) organisms and/or their products to humans and animals as food, feed and medicine, and b) Environmental safety, the safety of non-target organisms, soil and water. The terms biosecurity and biosafety are often used incorrectly as synonyms.

There is no risk-free technology. It was the international scientific community, not the activists, who have identified the possible biosecurity risks from the transgenic crops and devised protocols for the identification, assessment, quantification and mitigation of risk. Science has reasonable peer reviewed experimental evidence to answer biosecurity concerns.

Biosecurity issues are unfortunately often mixed up with political, economic, management, societal and ethical issues, emotionalizing and sensationalizing the concerns, to spread fear and suspicion of GE technology. The biosecurity issues raised to oppose GE crops by antitech activists are relevant to even products of classical agricultural biotechnology, but were never made an issue in that context.

4.2 Indian Biosecurity Regulatory Regime

Every country that commercializes GE products has a strict regulatory regime to ensure biosecurity of GE products and that all questions are answered reasonably satisfactorily before commercialization is permitted. India has a regulatory regime that is actually more stringent than that of most other countries. Powered by several Acts of Government, managed by the Department of Biotechnology and the Ministry of Environment and Forests, and supported a large number of public sector research institutions and scientists, the Indian regulatory regime functions satisfactorily.

It would take about six years for a transgenic crop to be taken outside the green house for strip (field) trials in small plots (about 10 x 100m) on the developer’s own land.  This will be followed by small scale multi-location research trials on leased land mainly for trait efficiency and later by large scale multi-location research trials on leased land of about 100 acres in all probable regions of commercial cultivation to evaluate trait efficacy, agronomic performance and biosecurity, involving a number of specialist institutions.  On a satisfactory performance of the GE crop in all the evaluations, commercialization will be permitted.  The process takes 10 to 15 years and costs several crore rupees.   The public sector institutions cannot raise this kind of money and so commercialization of a number of public sector GE crops is either delayed or even abandoned.

The Indian regulatory process should satisfy different provisions in several Acts of Government, such as a) Prevention of Food Adulteration Act 1954, b) Environment Protection Act 1986  (Rules of 1989), c) Recombinant DNA Guidelines 1990, d) Research in Transgenic Plants Guidelines 1998, e) Protection of Plant Varieties and Farmers’ Rights Act, 2001, f) National Seed Policy 2004/05, g) Patent Act Amendment 2005, h) Food Safety and Standards Bill 2005,  and i) Labelling Rules (under processing).

This process involves the following Central Ministries at one or the other stage: a) Environment and Forests, b) Science and Technology, c) Agriculture, d) Health and Family Welfare, and e) Commerce. 

The Indian regulatory framework is supervised by the following competent authorities: a) Recombinant DNA Advisory Committee (RDAC), b) Institutional Biosafety Committees (one for each institution in GE development) (IBSC), c) Review Committee on Genetic Manipulation (RCGM, with the Department of Biotechnology)), d) Genetic Engineering Approval Committee (GEAC, with the Ministry of Environment and Forests, is the apex body, that approves large scale field trials and release of GE crops into the environment for commercialization on receiving satisfactory inputs from the ICAR and RCGM), e) State Biosafety Coordination Committees (SBCCs, one for each State that develops or cultivates GE crops), and f) District Level Committees (DLCs, one for each district that develops or cultivates GE crops). 

The Indian Government have issued the following documents to guide product developers and evaluators through the regulatory oversight: a) Handbook for IBSC Members (2005), b) Regulatory Frame Work for GMOs in India (2007), and c) Guidelines and Standard Operating Procedures for Confined Field Trials of Regulated, Genetically Engineered Plants (2008).
A number of public sector organizations such as the a) the Indian Council of Agricultural Research (ICAR), b) the Indian Council of Medical Research (ICMR), c) the State Agricultural Universities (SAUs), and d) the Drugs Controller General of India (DCGI) are contextually involved in biosecurity regime. 

The ICAR and its institutions evaluate agronomic performance and environmental safety and recommend the crop for commercial release.  The SAUs and the State Departments of Agriculture are involved in the pre- and post-release monitoring of the GE crops.

The following research institutions are contextually involved in the evaluation of GE crops: a) Indian Agricultural Research Institute, New Delhi (IARI), b) Indian Institute of Horticultural Research, Bangalore (IHRI), c) National Centre for Plant Genome Research, New Delhi (NCPGR), d) National Botanical Research Institute, Lucknow (NBRI), e) National Research Centre for Weed Science, Jabalpur (NRCWS), f) Central Rice Research Institute, Cuttack (CRRI), g) Directorate of Rice Research, Hyderabad (DRR), and h) Central Potato Research Institute, Simla (CPRI).


Bt being a universally occurring soil bacterium, all species of plants and animals in agricultural and other situations, and those that use plants as food have been exposed to Bt and Bt proteins for centuries. Bt proteins are transient in the environment. The toxicity of Bt proteins is pest specific, dependent upon a set of biological pre-requisites. The use of Bt as a conventional pesticide for over 70 years has demonstrated that it is safe to the consumers and a variety of non-target organisms.  Nevertheless, antitech activists raise the following safety concerns repeatedly, ignoring massive evidence on product efficacy and biosecurity of GE crops.

5.1 Toxicity

Bt proteins were shown to be harmless to vertebrates, including mammals and humans, even at high doses, by ingestion, inhalation or injection.

Bt is one of the few pesticides recommended for widespread application in North America (Glare and O’Callaghan, 2000), and was broadcast or sprayed on crops and air sprayed to control forest pests in Utah (US, 1990-1995) and Ontario (Canada, 1985- 1994). Water borne Bt was air sprayed to control the Asian gypsy moth in Vancouver (Canada, 1988), and North Carolina (US, 1993) and the white-spotted tussock moth in Auckland (New Zealand, 1996) and no adverse effects on the human health have been reported so far from these urban locations.

Over 350 million people in North America have been eating Bt products for over a dozen years and no greater testimony is needed for human safety of Bt transgenic products than this.

With the considerable reduction of pesticide application on Bt crops, the risk from pesticide poisoning to non-target organisms, farm workers and consumers has been greatly reduced.

5.2 Allergenicity

Several claims have been made of allergenicity of transgenic crops, including Bt cotton in some places in India, but there has never been any scientific evidence (Kameswara Rao, 2009).  The Consensus Document from the Organization for Economic Cooperation and Development (OECD, 2007) on the safety of Bt proteins in transgenic plants observed that no allergenic amino acid sequences have been discovered in Bt crops now in cultivation
Allergenic reactions from many common foods and drugs cause several deaths every year. Yet, there was not even a simmer of protest against marketing such products.


All the evidence indicates that Bt transgenics are very safe to all components of the environment. Over a decade’s cultivation of Bt transgenics has neither confirmed the scary scenarios aired by the critics nor have thrown up any new threats to the environment.

6.1 Super Weeds

A serious negative factor projected by the antitech activists is that the transgenic crops would escape cultivation and become super weeds placing other vegetation at risk. Crawley et al., (2001), basing on a 10-year study of pest and herbicide tolerant transgenic Crops, demonstrated that the transgenics do not become more competitive to invade the environment as super weeds, but that in fact they perished earlier than their isogenic counterparts.  So far, none of the GE crops have escaped the cultivated field to invade the environment.

6.2 Impact of Bt on Non-target Organisms

Glare and O’Callaghan (2000) and every country’s regulatory process provide extensive data demonstrating the safety of Bt proteins to non-target organisms.

The much publicized instance of toxicity of Bt corn pollen proteins to non-target organisms (Monarch butterflies; Losey et al., 1999), was reinvestigated and disproved (Sears et al., 2001).  The performance of bumble bees was not affected in any manner by Cry 1Ab Bt proteins (Babendreier et al., 2008). Chen et al., (2008) showed that Cry1C proteins were safe to parasitoids that control pest populations in many crops, in contrast to the severe damage caused to the parasitoids by the traditional insecticides.

Reports of the death of peacocks and the death of farm animals in Andhra Pradesh and honey bee Colony Collapse Disaster in Europe and North America, deliberately attributed to the presumed toxicity of Bt proteins in GE crops, were shown to be due to causes other than Bt protein toxicity (Kameswara Rao, 2008 a,b).

6.3 Gene Flow From Transgenics

The possibility of gene flow from transgenics and the negative impact of this on other crops, biodiversity and the environment occupy a prominent position in discussions that denigrate modern agricultural biotechnology, although the experience gained from the regulatory processes of transgenic crops and their cultivation for over two decades have not indicated any serious possibilities of gene flow or its negative consequences. Gene flow depends upon the reproductive biology and breeding behaviour of the crop in question (Kameswara Rao, 2008 c,d), which the activists do not take into consideration.

6.4 Vertical Gene Flow

The essential pre-requisite for vertical gene flow is sexual reproduction between the transgenics and related plants. The ease of vertical gene flow depends upon the genetic relationships between the varieties and whether the crop is self or open pollinated, which Bt technology does not change. Transgenics are no more promiscuous than their isogenics. If vertical gene flow were possible between isogenics and any related varieties or species, it would be so between transgenics and related plants too.

A study, much quoted by the critics as evidence of vertical gene flow, which relates to Bt maize in Mexico (Quist and Chapela, 2001), was reinvestigated and disproved (Ortiz-Garcia et al., 2005). 

The floral structure and pollination behavior of such Bt crops as tomato, potato, bell pepper and brinjal does not warrant any significant threat from gene flow among these crops or their supposed relatives (Kameswara Rao, 2008c,d).

6.5 Lateral/horizontal gene flow

Lateral/horizontal gene flow involves exchange of genes between genetically unrelated organisms, a fact of evolution, but not of day-to-day occurrence. It does not involve sexual reproduction and the transferred genes can express in the same generation.

The use of antibiotic markers in transgenic technology, to confirm genetic transformation is used to promote fear of GE technology, including that in Bt brinjal. It is argued that the antibiotic resistant genes would be taken up by pathogens through lateral transfer and cause diseases that cannot be cured by the known antibiotics.  Supported by numerous studies, Ramessar et al., (2007) concluded that there is no scientific basis to argue against the use and presence of selectable antibiotic resistant marker genes in transgenic plants. However, to assuage the fears expressed, alternatives to antibiotic resistance marker genes (for example Mannose Phosphate Isomerase in Golden Rice2) are now used or antibiotic marker genes are removed, after confirming genetic transformation.

6.6 Impact on Biodiversity

A comprehensive report on the impact of agricultural biotechnology on biodiversity (Amman, 2004) reiterated that the introduction of GE crop varieties does not represent any greater risk to crop genetic diversity than the varieties of conventional agriculture. GE actually increases crop diversity by adding new varieties.

A peer reviewed report (Sanvido et al., 2007) concluded that no aspect of credible science based on ten years of field research and commercial cultivation has indicated that GE crops have harmed biodiversity or the environment.

The Consensus Document from the Organization for Economic Cooperation and Development (OECD, 2007) on the safety of Bt proteins in transgenic plants did not identify any hazards caused by them.

6.7 Terminator Technology

The most fallacious charge repeatedly made by the activists is that GE crops contain the terminator gene that prevents the farmer from using the seed to raise the next season’s crop.  The fact is that there is no terminator gene in any crop anywhere in the world.  The technology is prevented from use by voluntary corporate undertakings and/or governmental prohibitions and will not be used to affect the farmers’ interests.

6.8 Farmer Suicides

Although not an issue of biosecurity, activists compulsively attribute farmer suicides in India to the failure of Bt cotton.  Gruere et al., (2008) and other studies have shown that Bt cotton in is not related to farmer suicides in India. 


The All India Coordinated Vegetable Improvement Project and the Indian Institute of Vegetable Research, Varanasi (ICAR) have evaluated the agronomic performance and environmental impact of Bt brinjal (Choudhary and Gaur, 2009).

The Mahyco Research and Life Sciences Centres (MRC) conducted the following studies on Bt brinjal:  a) MRC, Kallakal, Andhra Pradesh:  substantial equivalence of Bt and non-Bt brinjals, b) MRC, Dawalwadi, Maharashtra: protein expression, effects of cooking and protein in cooked fruit and c) MRC, Ranebennur, Karnataka and Jalna, Maharashtra : pollen flow ((15 to 20 m; 1.46 to 2.7 per cent out crossing)

The following public and private sector institutions were involved in conducting various biosafety evaluations of Bt brinjal:

a) G. B. Pant University of Agriculture and Technology, Pantnagar: Feeding studies in lactating crossbred dairy cows;

b) Advinus Theraputic, Bangalore: Subchronic (90 days) feeding studies using New Zealand rabbits, b) Subchronic (90 days) feeding studies in Goats;

c) Intox, Pune: a) Acute oral toxicity studies in rats, b) Sub chronic oral toxicity study in Sprague Dawley rats,

d) Mucous membrane irritation test in female rabbit and d) Primary skin irritation test in rabbit; 

e) Rallis India, Bangalore: Assessment of allergenicity using Brown Norway rats;

f) Central Avian Research Institute, Izatnagar: Effect on performance and health of broiler chicken;

g) Central Institute of Fisheries Education, Mumbai: Responses, as a dietary feed ingredient to common carp (Cyprinus carpio) on growth performances;

h) All India Coordinated Research Project on Vegetable Crops, Varanasi: Effects on non-target and beneficial insects; and

i) Indian Institute of Chemical Technology, Hyderabad: Chemical fingerprinting of Bt and non-Bt brinjal (including alkaloids).

All these studies have shown that Bt brinjal is functional and is as safe as non-Bt brinjal for human consumption and to the environment (Choudhary and Gaur, 2009). 

From the time of initiation of development till commercial release, a GE crop involves over 10 years of research by over 150 scientific and technical personnel.  Nearly two decades of experience in the development of Bt crops (including potato, tomato and bell pepper related to brinjal) and over 13 years of experience in their commercialization in nearly 30 countries has built up an enormous amount of biosecurity data that convincingly demonstrate their benefits and safety.  Bt brinjal has been adequately tested and found to be functional and safe.  The activists trash this body of positive evidence and demand an irrational global ban not just on Bt brinjal but on all GE crops.  Levels of public awareness of the benefits of GE technology being low, the activists have used every trick of the trade to mislead the public.  The scientists, product developers and the Governments, who are engaged in GE technology deployment, have not done anything to educate the public on the efficacy, reliability, safety and benefits of GE crops and our sound regulatory regime.  Enhanced public awareness of these issues will promote informed decisions and wider acceptance of technology, and prevent the misuse of the media by the activists to hijack public opinion to serve vested interest.


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November 5, 2009