Various Issues around Bt Cotton in India

Bt cotton, a transgenic plant which produces an insect controlling protein Cry1A(c), the gene for which has been derived from the naturally occurring bacterium, Bacillus thuringiensis subsp. kurstaki (B.t.k.). The cotton hybrids containing Bt gene produces its own toxin for bollworm attack thus significantly reducing chemical insecticide use and providing a major benefit to cotton growers and the environment.

Please note that Bt cotton contains the three genes viz. Cry1Ac, NPTII and AAD inserted via genetic engineering techniques.

  • The Cry1Ac gene, which encodes for an insecticidal protein, Cry1Ac, derived from the common soil bacteria Bacillus thuringiensis subsp. kurstaki (B.t.k.).
  • The NPTII gene and the AAD gene encode for the NPTII and AAD proteins and they are used as a selectable marker and have no pesticidal activity and are not known to be toxic to any species.
Rationale of Use of Bt Cotton

Bt refers to the bacterium Bacillus thuringiensis which naturally produces a chemical harmful only to a small fraction of insects, most notably the larvae of moths and butterflies, beetles, and flies, and harmless to other forms of life. To produce the GM Cotton, the gene coding for Bt toxin (Cry-1-ac) has been inserted into cotton, causing cotton to produce this natural insecticide in its tissues. By this, the larvae are killed by the Bt protein in the GM cotton they eat. This eliminates the need to use large amounts of broad-spectrum insecticides to kill various pesticides.

Extent of Use

Bt cotton was planted on an area of 25 million hectares in 2011. This was 69% of the worldwide total area planted in cotton. GM cotton acreage in India grew at a rapid rate, increasing from 50,000 hectares in 2002 to 10.6 million hectares in 2011.

The total cotton area in India was 12.1 million hectares in 2011, so GM cotton was grown on 88% of the cotton area. This made India the country with the largest area of GM cotton in the world. The U.S. GM cotton crop was 4.0 million hectares in 2011 the second largest area in the world, the Chinese GM cotton crop was third largest by area with 3.9 million hectares and Pakistan had the fourth largest GM cotton crop area of 2.6 million hectares in 2011. Australia is the country with the fifth largest GM cotton crop in the world.

Other countries using GM cotton are Argentina, Myanmar, Burkina Faso, Brazil, Mexico, Colombia, South Africa and Costa Rica.

Introduction in India

We have already discussed that all transgenic crops in India require environmental clearance under 1989 rules notified under the Environment (Protection) Act, 1986. Since Bt cotton is a genetically modified plant, it was never clear whether it was safe or not. The initial formal sector studies conducted by the Industry and Government most likely found the positive agro-economic effects of Bt Cotton. These studies were reported in the Parliament from officially sanctioned field trials of Bt cotton. The studies were confirmed by the advocates of the Bt Cotton that it resulted in increased yield because of superior bollworm control; bringing down cost of bollworm control and thereby raising the net incomes of the farmers.

Thus, official approval of Bt Cotton was granted in March 2002, thus Bt Cotton became the first GM crop approved in India. Mahyco became the first Indian company to commercialize transgenic cotton hybrids in India in 2002.

Commercial cultivation in Bt cotton was launched in Six States viz. Andhra Pradesh,Gujarat, Karnataka, Madhya Pradesh, Maharashtra, Tamil Nadu.

The GEAC had accorded conditional approval for introduction of three Bt cotton hybrids namely BT MECH 162, BT MECH 184, BT MECH 12 after detailed evaluation on the efficacy and safety of the product. Some of these conditions were as follows:

  • The crops were approved for a period of 3 years (2002-2005)
  • Every field where Bt cotton is planted shall be fully surrounded by a belt of land called ‘refuge’ in which the same non-Bt cotton variety shall be sown. The size of the refuge belt should be such as to take at least five rows of non-Bt cotton or shall be 20% of total sown area whichever is more. To facilitate this, each packet of seeds of the approved varieties should also contain a separate packet of the seeds of the same non-Bt cotton variety which is sufficient for planting in the refuge defined above.
  • Each packet should be appropriately labelled about the Bt seeds in vernacular language
  • MAHYCO will enter into agreements with their dealers/agents, that will specify the requirements from dealers/agents to provide details about the sale of seeds, acreage cultivated, and state/regions where Bt cotton is sown.
  • MAHYCO will prepare annual reports and submit the same in electronic form to GEAC
  • MAHYCO will develop plans for Bt based Integrated Pest Management and include this information in the seed packet.
  • MAHYCO will monitor annually the susceptibility of bollworms to Bt gene
  • MAHYCO will deposit 100 g seed each of approved hybrids as well as their parental lines with the National Bureau of Plant Genetic Resources (NBPGR).

What is MECH?

The natural gene cry 1ac has been further modified by Monsanto Inc., USA. The transgenic cotton varieties containing this improved gene have been branded ”Bollgard” by Mahyco. Mahyco has produced Bt cotton lines by back-crossing the Bt lines of Monsanto with existing cotton hybrids. These lines have been named MECH (Mahyco’s early cotton hybrid) with a number suffixed such as 12, 162, 184 and 915.

Biosafety assessment by Government / Mahyco

The following are some of the relevant conclusions obtained after the various studies conducted by safety assessment of the Bt Cotton Hybrid seeds. These conclusions have been sourced from an environment ministry document

  • The pollens of the Bt Cotton Hybrids are able to pollinate mostly within a range of 2 meters and only 2% of the pollens are able to reach a distance of 15 meters thus the chances of cross pollination with Non-Bt hybrids are meagre. Thus, there is essentially no chance that the Bt gene will transfer from cultivated tetraploid species such as the Bt hybrids to traditionally cultivated diploid species.
  • There was no substantial difference found between Bt and non-Bt cotton for germination and vigour, indicating that there is no substantial difference between transgenic Bt and control non-Bt cotton with regard to their weediness potential.
  • Bt cotton hybrids do not have any toxic effects on the non -target species such as sucking pests (aplvels, jassids, white fly and mites). The beneficial insects (lady beetle, spiders) remained active in both Bt and non Bt varieties.
  • Bt protein was not detected in soil samples indicating that Bt protein is rapidly degraded in the soil on which Bt cotton is grown. The half-life of the Cry 1AC protein in plant tissue was calculated to 41 days which is comparable to the degradation rates reported for microbial formulations of Bt. Thus there was no possible risk of accumulation of Btgene in the soil
  • There was no significant difference in population of microbes and soil invertebrates like earthworm and Gllembola between Bt and non-Bt soil samples.
  • There is no change in the composition of Bt and non Bt seeds, with respect to proteins, carbohydrates, oil, calories and ash content.
  • No significant differences in feed consumption, animal weight gain and general animal health were found between animals fed with Bt cotton seed and no cottonseed. No significant differences were found between animals fed with Bt and non Bt cottonseed.
  • Cry 1AC gene and protein are not found in refined oil obtained from Bt cottonseeds. Bt cotton seed meal is nutritionally equivalent, wholesome and safe as the non-Bt cottonseed meal.
  • The transgenic Bt Cotton plant was developed by incorporating Bt gene into it. Therefore it was desirable to assess that no other gene including cre recombinase gene which is an integral component of the so called “terminator technology” is present in Bt cotton. A study was carried out by The Department of Genetics, University of Delhi to check the presence/absence of such gene in the Bt cotton. The PCR analysis showed the absence of “terminator gene” in Bt cotton hybrids.

Controversies and Farmer Distress Issue on Bt Cotton

The environmentalists, farmers, scientists and political parties raised concerns over environmental issues, bio-safety measures, and health implications of the Bt Cotton. The growing number of farmers committing suicides in some cotton growing states has re-ignited the protests against the Bt Cotton. The question was: Is Bt Cotton connected to farmer’s suicides? Arguments in favour and against this have flooded in media. Here is our version of analysis on this debate.

Undoubtedly, Bt technology has been responsible for farmer distress in the country. There are two main arguments being this. Firstly, indiscriminate use of Bt hybrids instead of Bt straight. Secondly, problem of later maturing hybrids.

Indiscriminate use of Bt Hybrids

The Bt Technology does just one thing – to protect the crop from boll worms and few other caterpillars. Nothing else. Bt Cotton is available in two forms viz. Bt Hybrids and Bt straight (non-hybrid). Soon after its launch, India became a market playground of companies where thousands of brands of the Bt hybrids became available. Farmers found it impossible to make an informed decision from the randomly available brands. If we compare it with the rest of the world, we find that Bt cotton is available only as a few straight varieties elsewhere. Thus, the first mistake India did was to allow the Bt Hybrids rather than limited Bt Straight varieties. The indiscriminate use of Bt hybrids was for a great length responsible for distress among cotton farmers in rain-fed areas.

Late Maturing Hybrids

In India, Cotton is an important rainfed crop. Most of the Bt hybrids are of 180-to 200-day duration and are not suitable for rain-fed conditions. Since the Hybrid seeds are costly, they are sown late, only when the farmers ensured that there is adequate soil moisture. The boll formation in the late sown maturing hybrids suffers from severe moisture stress because it takes place much later after the rains recede. This ultimately results in low yields. Instead, the advantage with straight varieties would have been that farmers can reuse farm-saved seeds and can take the liberty of early dry sowing, even before the onset of the monsoon, without having to worry about the risks of poor germination and re-sowing. Then, many of these hybrids are susceptible to sap-sucking insects, leaf-curl virus and leaf reddening, adding to input costs.

The above two are major reasons as to why Bt Cotton is not directly connected with farmer suicides or with enhanced requirement of fertilisers or water. The problem is with late maturing hybrids that do not perform well owing to the late-season moisture deficit in shallow soils, especially when they are sown late. Farmers in rain-fed regions were / are compelled to choose from a long list of Bt hybrids, most of which are late maturing, sucking pest-susceptible hybrids, that are unsuitable for rain-fed regions.

But despite that, there is no doubt that the Bt technology has brought down the use of pesticides by about 50% and declined infestation of the boll worm. However, Bt cotton has not led to increase in cotton yields significantly. Cotton yields increased by about 60 per cent in three years between 2002 and 2004 when the area under Bt cotton was a meagre 5.6 per cent and the area under non-Bt cotton was 94.4 per cent. The yields did not increase significantly more than the pre-Bt era even until 2011 when the Bt cotton area touched 96 per cent.

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