Green signal for Bt-cotton

The Genetic Engineering Approval Committee clears the commercialisation of the first transgenic cotton variety, making India the eighth country to introduce this genetically modified crop.

MARCH 26, 2002, marked the beginning of an era in Indian agriculture. That day the government gave the green signal for the commercialisation of the first transgenic, or genetically engineered crop (GEC). It comes in the form of hybrid Bt-cotton, a transgenic cotton variety resistant to American Bollworm (Helicoverpa armigera), which is known to destroy over 50 per cent of the crop in India.

India is now one of the 16 countries where commercial plantation of GECs is permitted. To put matters in perspective, the estimated global area of genetically modified (GM) crops for 2001 is 52.6 million hectares. During the six-year period 1996-2001, the global area under transgenic crops increased more than 30-fold, from 1.7 mha in 1996 to 52.6 mha in 2001. The principal GECs were: GE soybean occupying 63 per cent of global area, followed by GE corn at 19 per cent, transgenic cotton at 13 per cent and GE canola at 5 per cent. China had the highest year-on-year growth with a tripling of its Bt cotton area from 0.5 mha in 2000 to 1.5 mha in 2001. Transgenic cotton is today grown over 6.8 mha in seven countries: the United States, Australia, South Africa, Argentina, Mexico, China and Indonesia. India will be the eighth country to introduce it.

The Indian transgenic cotton hybrid has been developed by the Maharashtra Hybrid Seeds Co. Ltd. (Mahyco), a Mumbai-based private company, using the genetically engineered insect-resistant cotton seed and the technology obtained from the American multinational Monsanto Inc. The plant has a foreign gene obtained from a soil bacterium Bacillus thuringiensis (Bt) that codes for a protein toxic to the American bollworm, which has been genetically engineered into its genome. As a sprayed bio-pesticide, this Bt-toxin has been in use for cotton and other crops. But, with the gene for Bt-toxin built into the genetic make-up of the transgenic crop, the plant produces its own pesticide in the form of Bt-toxin all the time in its various parts and thereby acquires resistance to the pest.

The approval for the commercial release of Mahyco's Bt-cotton was given by the Genetic Engineering Approval Committee (GEAC) of the Ministry of Environment and Forests (MoEF), the statutory body set up for approving large- scale (research or commercial) use of genetically engineered organisms (GEOs) following the rules enacted in 1989 under the Environment Protection Act (EPA), 1986. The GEAC is the apex clearing authority in the three-tier regulatory structure after bio-safety studies and small-scale field trials are evaluated by the Review Committee for Genetic Manipulation (RCGM) and the Monitoring and Evaluation Committee (MEC) of the Department of Biotechnology (DBT). In granting clearance, the GEAC considered the highly favourable results of extensive field trials - both small-scale and large-scale - carried out across the country in over 400 locations by Mahyco since 1997 and those of the independent large scale trials by the Indian Council of Agricultural Research (ICAR) in 11 of its centres in central and southern India under its Advanced Varietal Trials of the All India Coordinated Cotton Improvement Project (AICCIP).

In some sense, the clearance by the GEAC was inevitable and merely of academic interest after the incident last November in Gujarat where illegal planting and seeding of Bt-cotton over nearly 4,500 ha had taken place. A Hyderabad-based company, Navbharat Seeds Co. Ltd., had been growing Bt-cotton seeds (Navbharat 151) in Nandyal, Andhra Pradesh, and selling it in various parts of the country. The seed had the same Bt-toxin gene as that of Monsanto/Mahyco but in a different parental line. By the time this was detected (apparently on a complaint from Mahyco) it was harvest time and cotton was ready to be picked and marketed. The GEAC first ordered the Gujarat State Biotechnology Coordination Committee to burn all the illegal plantations but later, at the instance of the Gujarat government (which in turn was under pressure from farmers), withdrew the order and ordered that the cotton be procured from the farmers at suitable price, the lint separated and stored till further orders and the seeds destroyed.

Of course, before this order could be implemented, the cotton had reached the market and the seeds sold to numerous farmers. While the GEAC and the Gujarat government claim that much of the illegal crop output has been procured, there is no denying that a substantial quantity of Bt-cotton and seeds are already in the market and probably ready to be sowed again this year. According to media reports, which officials of the MoEF and the DBT have not denied so far, transgenic seeds are being sold in the markets of Andhra Pradesh and Gujarat. While the State bodies have been alerted, it is clearly beyond the capacity of law-enforcing bodies to check its illegal spread. A case was registered against Navbharat Seeds Co. Ltd. in the Gujarat High Court on November 12, 2001, for violating the EPA but the court is yet to decide on the case. According to sources in the DBT, the illegal Bt-cotton is not actually a hybrid but a non-indigenous variety, which means there is no loss of vigour in the next-generation seeds (as is the case with hybrids) and the seeds stored by farmers would be equally viable for the next generation crop. Therefore, besides the unknown environmental and ecological impact, the diffusion into the market of the illegal Bt seeds poses a commercial threat to Mahyco as well, whose Bt-cotton is a hybrid necessitating the farmer to buy seeds for every crop.

The lobby of the medium and large-scale cotton growers too has been mounting pressure on various State governments. Even before the formal approval, the Punjab Agriculture Minister announced that Punjab would be introducing Bt-cotton shortly. More interestingly, according to questions answered in the Rajya Sabha on August 30, 2001, and March 1, 2002, by T.R. Baalu, Minister for Environment and Forests, the Karnataka government had formally asked the Centre to clear the commercial release of Bt-cotton immediately.

Dogged by controversies all along, for Mahyco to begin doing business in Bt-cotton it has taken exactly seven years since March 1995, when the company was granted permission by the DBT to import 100 gm of seeds of Bt-cotton from Monsanto. The multinational had genetically engineered the Bt-toxin gene known as cry1Ac into the American cotton variety Coker-312. Mahyco sought approval for field trials and commercialisation for stable Bt-cotton hybrid lines that it had developed by back crossings with elite Indian varieties. The controversies arose, on the one hand, from the extreme position of outright rejection of GEOs by certain environmental groups and non-governmental organisations and, on the other, from genuine concerns over aspects such as environmental safety and societal impact of GEOs in the Indian context. The latter included the possible migration of genes into non-target species and traditional crop varieties, thus impacting biodiversity, the rapid build-up of pest resistance to the toxic gene due to the presence of the toxin at all times, the unpredictable ecological impact of the GECs - in particular their effect on the soil microflora, the food chain and the environment in general - the unviability and impracticality of the GECs for the Indian farming community with very small individual holdings where the environmental safety models of the developed nations do not necessarily apply.

The GEAC's approval is for a limited period of three years, after which the performance will be evaluated, particularly with regard to the evolution of Bt-resistance in American bollworm, and it comes with a set of conditions that Mahyco has to comply with. Although the conditions are yet to be finalised owing to a lack of unanimity with regard to some of them, it is actually irrelevant because none of them is enforceable. Indeed, the Navbharat incident is already a pointer to that.

Of the six Indian hybrids into which it has introduced the Bt-toxin gene, Mahyco had sought approval for four. The final approval is, however, for three Mahyco hybrids designated as MECH-12 Bt, 162 Bt and 184 Bt. As regards the fourth, MECH 915 Bt, Mahyco is yet to submit the test hybrid to the ICAR for the latter's large-scale trials. According to the DBT, whose RCGM and MEC have supervised Mahyco's small and large-scale field trials, the company's trials with 915 Bt are already over and the results favour its introduction as well, particularly for the northern region.

The different hybrids that Mahyco has used to insert the Bt-toxin gene are all in use in the non-Bt form in different parts of the country. The hybrids differ in their agronomic characteristics and in their suitability to different regions. For instance, 915 is most suited to the north where damage owing to Pink bollworm (Pectinophora gossypiella I) is as significant as that caused by American bollworm. However, Bt hybrids other than 915 have been found not to confer any resistance at all to Pink bollworm in the north. The GEAC's limited approval may, therefore, not be great news for the Punjab farmers.

With regard to the environmental safety parameters set by the RCGM/MEC, the results are favourable, according to P.K. Ghosh, Adviser, DBT, and a member of the RCGM as well as the GEAC. In particular, with regard to its migration into the food chain, cotton oil has been found to have no detectable presence of the gene. But animal, poultry and fish studies have shown its ingestion to be safe. As regards efficacy against bollworm, the results of both Mahyco /MEC and ICAR trials indicate substantial reduction in the spraying requirements compared to controls.

Bt-toxin targets only the bollworm complex comprising the American bollworm, the Spotted bollworm (Earias vittella), the Spiny bollworm (Earias insulana) and Pink bollworm. In particular, the Bt-toxin, cry1Ac, is known to be highly specific to American bollworm, which attacks the plant after about 60 days of sowing, with its activity peaking at around 90 days. The Pink bollworm, on the other hand, begins to cause damage after about 130 days, the time of the first pick. Bt-toxin cry1Ac, however, has only a moderate impact on Pink bollworm and among the Mahyco hybrids, 915 Bt is known to have the strongest effect on it. But Bt toxin does not have any effect on the pests of the early phase, namely sucking pests like Thrips, Jassids and Aphids, which attack between 30 and 45 days of sowing. Therefore, while the number of sprays against bollworm would come down, there would be no reduction in sprays against the others.

According to both the sets of trials, the number of sprays against bollworm comes down to a maximum of three compared to six to 10 required for non-Bt-cotton depending on the severity. Because of a reduction in crop loss owing to bollworm infestation, there is an effective increase in yield. In Mahyco field trials, the increase ranges from 23 per cent to 88 per cent, according to Ghosh. The ICAR study, on the other hand, has recorded an increase in the yield of about 60 per cent in the central zone and over 100 per cent in the southern zone. Both the ICAR and the Mahyco /MEC studies estimate an economic advantage of Rs.8,000-Rs.10,000 a hectare.

There is, however, a slight difference in the conclusion with regard to the best hybrid between the two studies. The ICAR study, which appears to be more comprehensive than Mahyco's, shows that, considering all aspects of plant growth, yield, fibre quality and tolerance to pests and diseases, MECH 184 Bt ranked first, followed by 162 Bt. The latter is, however, found to be drought-tolerant and adapted to rainfed areas. MECH 12 Bt, which has superior fibre quality, is stated to be suitable for irrigated conditions. In terms of agronomic as well as plant breeding characteristics, two main parameters mandated upon the ICAR to evaluate, all hybrids show better performance than the non-Bt varieties.

A key issue in the use of Bt-cotton is the development of resistance to Bt in the pests. An important outcome of the trials is the generation of baseline data on the susceptibility of American bollworm to the Bt-toxin cry1Ac. Although the levels of protein expression do come down with time, the Mahyco hybrids have been found to produce high concentrations of cry1Ac protein which are at least an order of magnitude more than the lethal levels for the bollworm. The MEC report, however, says that a prediction of the number of generations of field population of bollworm required to develop resistance to Bt-cotton cannot be made at this stage. Laboratory studies at the Central Institute of Cotton Research (CICR), Nagpur, of the ICAR, however, indicate that the selection pressure of Bt-toxin brought about Bt-resistance after about eight to ten generations.

Besides Bt-cotton exerting a selection pressure on the American bollworm, studies at the Indian Agricultural Research Institute (IARI) have shown that the existing Indian bollworm population exhibits considerable spatial and temporal variability in the matter of susceptibility to the cry1Ac toxin. This implies a rapid build up of resistance to Bt-cotton. The concept of "refugia" in transgenic plantations has been devised to counter this resistance build up which is based on the following premise. A certain fraction of the area is planted with non-Bt-cotton - the refugia - which ensures that a sizable bollworm population does not come under the selection pressure and thus does not develop the resistance trait. The availability of this population for mating ensures that resistance does not develop in the pest population. Maintenance of refugia in the Bt-cotton fields is central to the conditions imposed by the GEAC on Mahyco.

Of course, to arrive at a critical size of the "refugia", model studies based on baseline susceptibility data are required. However, no such model has been developed in the country. In its absence, the GEAC has adopted the U.S. model where nine to 20 per cent area as "refugia" is recommended. In the Indian context, given the generally small holdings (less than a ha), the dispersal of the gene to neighbouring fields and other crops has also to be ensured. The Mahyco studies have shown that pollen dispersal occurs over a distance of about 2 to 5 m if there are trapper non-Bt cotton rows in the periphery of a field. Taking this aspect also into account, the original draft of the GEAC conditions said: "Non-Bt cotton should be planted in five rows or 20 per cent of the area, whichever is more, around the periphery." Accordingly, the conditions mandated Mahyco to sell with every packet of Bt-seeds for every acre, 20 per cent non-Bt seeds. But in typical small holdings of around one acre, this division would not be a profitable proposition. So, some GEAC members would instead like the phrase to be "whichever is less". But that would not be environmentally sound because large-area farmers would end up not setting up enough refugia resulting in adverse long-term impact with regard to Bt-resistance.

Although the conditions make it incumbent upon Mahyco to ensure that farmers comply with the stipulations (which it is expected to do by educating them about long-term objectives and the like), it is obviously not enforceable. Neither the Centre nor the State has the manpower or the wherewithal (technical and otherwise) to ensure this by monitoring every field. It is too much to expect a farmer to forgo profits from 20 per cent of his cotton crop voluntarily. In order to avoid such conundrums, the MEC had, in fact, recommended that contiguous areas be designated specifically for large area Bt-cotton plantation where such refugia would not undermine short-term profitability. For some reason, the GEAC has ignored this recommendation. GEAC Chairman A.M. Gokhale feels that the farmers would themselves realise the need for a cooperative or consortium approach and join hands to cultivate large contiguous areas with Bt cotton. Ghosh, while agreeing that mechanisms needed to be evolved to implement these, such as involving gram panchayats, feels that in the Indian context even if refugia are not maintained, other crops in the vicinity would act as refugia.

The conditions also require Mahyco to enter into a legally binding agreement with dealers to maintain a monthly record of seed sales and the buyer, details of the area where a particular bag of seeds will be sown among other things. Mahyco is also required to conduct studies continually at its own expense on, the spread of Bt-resistant bollworm population in different parts of the country. None of these seems implementable. The real reason behind the conditions seems to be merely to ward off criticism against inadequate resistance management plans.