Do we need GM mustard?

On October 25, the Union Ministry of Environment, Forests and Climate Change (MOEFCC) sent a letter to a Delhi-based plant geneticist and former VC of the University of Delhi that his application for environmental clearance of a transgenic (genetically modified) mustard variety, DMH-11, or Dhara Mustard Hybrid, which he had developed 20 years ago, is now cleared for environmental or field testing. The sudden decision, which goes against a Supreme Court ruling that had stayed the clearance of this variety for want of adequate scientific data on DMH-11, caught both scientists opposed to GM crops and ASHA (the Alliance for Sustainable and Holistic Agriculture), which had moved the Supreme court on the matter, by surprise. Let’s trace the manner in which the whole issue was fast-tracked and whether a transgenic hybrid mustard is needed for India at all at this juncture.

The ministry gave its approval for the GM mustard within a week of the Genetic Engineering Appraisal Committee (GEAC), India’s apex regulator for transgenic products, giving the go-ahead for the field trials. On October 31, the last day of the mustard sowing season in India, the ministry held a press conference in Delhi which was addressed by the heads of two key scientific bodies – the president of the National Academy of Agricultural Sciences (NAAS), and the chairperson of the Trust for Advancement of Agricultural Sciences (TASS) -- who assured the media that the Indian Council of Agricultural Research (ICAR) would conduct the field trials over the next fortnight in key mustard growing states such as Rajasthan, Haryana, Punjab, Uttar Pradesh and Madhya Pradesh.

Proponents of DMH-11 claim that a transgenic mustard variety is the need of the hour as developing a high-yielding and pest-resistant mustard variety using traditional crossbreeding methods is challenging. The plant is principally ‘self-pollinating’, which means that the male (anther) and female (pistil) reproductive parts are present in the same plant (like some in other species) and, therefore, plant breeders trying to cross two different parental lines to produce a hybrid with the desired traits will need to make one of the parents ‘male sterile’ to enhance cross-pollination. This, presumably, is a long and time-taking procedure. Genetic manipulation, on the other hand, allows scientists to overcome the problems and directly change the genetic make-up of a plant so that it exhibits the desired trait -- for example, resistance to a specific plant pest, either disease or insect attack (like the bollworm in cotton).

DMH-11 was created by using both hybrid and transgenic methods. The goal was to cross the native Indian mustard variety, Varuna, with an East European variety, Early Heera-2, which grows faster and produces more biomass (vegetative matter).

To make this possible, the scientists used a genetic engineering technique originally developed by Belgian geneticists in the 1990s to first induce male sterility in one of the parental lines and then restore fertility in the offspring. Two genes, barnase and barstar, were chosen from the soil bacterium Bacillus amyloliquefaciens and inserted into the DNA of the mustard plant. Within the anther, barnase selectively destroys the cell layer that surrounds the pollen sac in the anther (the male part of the flower), preventing pollen formation and thereby leading to male sterility. Barstar subsequently suppresses the activity of barnase in the progeny and restores fertility. “Additionally, we have used another gene called bar from Streptomyces hygroscopicus bacteria”, say the scientists. The bar gene provides resistance to Glufosinate ammonium, an herbicide that keeps weeds in check in mustard fields.

What do GM opponents say?

This insertion of the alien genetic material from a soil bacterium (as in the case of Bt cotton, where a gene from the soil bacterium Bacillus thuringiensis was used to create resistance against the pink cotton bollworm, hence called Bt cotton by Monsanto, which has now faded out of Indian cotton fields due to severe attack by other pests, in addition to bollworm) portends possible risks. This is why the Supreme Court was nudged to stay the clearance for environmental release of DMH-11.

The reality on the ground is that if one were to go back to the field experience with Bt cotton, where Monsanto used the Cry 1 Ac gene from Bacillus thuringiensis to impart resistance to pink bollworm in cotton, the press had reported on July 10, 2010, that Monsanto had clearly admitted failure of its Bt cotton, popularly known as Bollgard 1, in Amreli, Bhavnagar, Junagarh and Rajkot in Gujarat; in Punjab, farmers had lost thousands of hectares of Bt cotton due to other pest attacks. Ironically, the then science minister Prithviraj Chauhan had written in his letter to the then health minister, A Ramadoss, that Bt cotton was a “great success”. No one talks of Bt cotton in India anymore.

But more worryingly, the following are some of the pertinent questions to be considered before India enters into a race on a food crop like mustard:

1. The comparison of DMH-11 has been made with Varuna, which is a low-yielding mustard variety.

2. What about honey production in India? Honey exporters fear that the introduction of DMH-11 will sound the death knell for their business. Those targeting overseas markets entirely depend on bees feeding on the nectar of mustard flowers. Mustard honey crystalises rapidly and makes export to US and EU feasible. But these countries also insist on GM-free certification. What will happen to the Indian honey export business?

3. Honeybees can transfer pollen from DMH-11 to other neighbouring plants, which will lead to horizontal and undesirable gene transfer and create superweeds.

4. The parental lines of DMH-11 also require approval for environmental clearance. Has this been done?

5. There are non-GM mustard hybrid varieties which provide yields up to 3,200kg/ha. With good crop management, Indian mustard can yield much more.

Finally, one must say that if approval is provided for the controversial GM mustard, the floodgates for all other food crops would also open. That, indeed, would be an environmental and safety hazard for India if one goes by the practical and field experiences from other countries.

(The writer is a former Professor, Science Foundation, The Royal Society, Belgium)