India to plant first herbicide-tolerant GM crop

The coming kharif season could witness plantings of the first ‘stacked trait' genetically modified (GM) crop in the country.

The Maharashtra Hybrid Seeds Company (Mahyco) has already completed the second-stage Biosafety Research Trials (BRL-2) for four cotton hybrids that harbour two sets of traits – the first for insect resistance and the second for herbicide tolerance.

The hybrids will, in all, incorporate three foreign genes. The first two, cry1Ac and cry2Ab, are isolated from a soil bacterium, Bacillus thuringiensis or Bt. While the cry1Ac gene produces proteins toxic against the American bollworm, spotted bollworm and pink bollworm, the cry2Ab gene confers resistance to spodoptera pests (beet and fall armyworms).

New Gene

The third gene, cp4-epsps, codes for a totally different trait of tolerance against glyphosate. The latter is a herbicide used to control grasses and broad-leaf weeds that grow along with the crops and impact yields by competing for nutrition and water. Being a non-selective, systemic chemical that kills all plants in the field of application – be it weeds or the crop in question – glyphosate cannot be used on ordinary cotton hybrids and varieties.

The cp4-epsps gene – sourced from yet another soil bacterium, Agrobacterium tumefaciens – expresses a protein, which inhibits the action of glyphosate. Plants that are genetically engineered to contain this gene are, hence, rendered ‘tolerant' to glyphosate, enabling farmers to apply it in place of manual weeding.

The Mahyco cotton hybrids that have undergone confined BRL-1 and BRL-2 multi-location field tests over three seasons (2008, 2009 and 2010) are set to be the first GM crops in India to harbour herbicide-tolerance trait.

The GM crops being cultivated now are all cotton hybrids containing various Bt genes imparting only insect pest resistance. These are based on proprietary ‘events' – a series of steps and protocols developed to insert a foreign gene into a host plant – of Monsanto, JK Agri Genetics, Nath Bio-Genes, the Rallis India-controlled Metahelix Life Sciences and the Central Institute for Cotton Research, Nagpur (CICR).

The latest Mahyco hybrids combine two Monsanto events: MON-15985 (which is already incorporated in the existing Bollgard-II cottons being grown since 2006) and MON-88913 (a new event). That would make them the first ‘stacked event/trait' GM products to be introduced in the country.

Appraisal before Approval

"The BRL-2 trials were conducted under the supervision of the CICR, which is likely to submit its report to the Genetic Engineering Appraisal Committee (GEAC) by the month-end. As the GEAC normally meets every second Wednesday, it may consider the matter on April 13, paving the way for commercial planting in kharif 2011”, sources told Business Line.

Mahyco, they added, has already undertaken production of around 55,000 packets, containing 450 grams each of the four new GM hybrids, of which two (MRC-8017 and 8031) are for northern States and the remaining (MRC-8347 and 8351) for the south and central zones. The 55,000 packets would suffice for 50,000-odd acres, which can go up in subsequent seasons.

In 2010, GM hybrids/varieties accounted for 9.4 million hectares (mh) out of the country's total 11 mh cotton area. Within the 9.4 mh, 90 per cent incorporated Monsanto's MON-531 and MON-15985 events, with the latter alone covering 6.6 mh.