Other environmental concerns apart, GM mustard could also send bees buzzing away

More than six years after a moratorium on Bt Brinjal halted the development of the transgenic vegetable, a sinister game is being played again.

This time, it is the mustard crop that is under the threat of being replaced by an ill-tested, gene-altered version, whose impact on the ecosystem remains unknown.

What primarily motivated the Ministry of Environment and Forest to impose the moratorium on Bt Brinjal was the lack of a suitable bio-safety and risk assessment mechanisms for genetically engineered crops in the country. Over the years, not much has changed on this front.

Why, then, is the government so keen on pressing ahead with the Dhara Mustard Hybrid-11, or DMH-11?

A scrutiny of the Assessment of Food and Environmental Safety document put together by the Ministry of Environment and Forest on the proposal for Authorisation of Environmental Release of Genetically Engineered Mustard (Brassica juncea) Hybrid DMH-11 reveals serious lacunae in the assessment protocols.

The alarming haste with which the government plans to introduce genetically modified mustard to Indian fields shows its sheer disregard for human and environmental concerns.

Impact on bees

Let’s take the case of bees. The yellow mustard flowers in full bloom are not only a treat for the eyes, they are a treat for bees as well, making them a favourite among beekeepers. But the importance of bees to the mustard plant has been completely and conveniently overlooked in the proposal for GM Mustard.

Bees play a crucial role in sustaining life on earth. However small they are, the buzz they create has a wide impact. The pollen grains they carry are responsible for the pollination of 75% of crops globally, including mustard. This is how new seeds are created and this has been nature’s way of striking a delicate balance. For India alone, the worth of insect pollination in important vegetable crops is $726 million.

The mustard crop has 10-20% dependency on bees for pollination, which leads to the creation of new seed sets. Thus, pollen flow from the genetically enhanced mustard is a major concern.

A decrease in pollinator populations can bring about a pollination deficit. This reflects on the health and subsequently, the population of pollinators around the fields. In other words, we need to know how DMH-11 can impact the health of pollinators. Is there an adequate bee population around the DMH-11 fields? Page 84 of the Assessment of Food and Environmental Safety document answers this in one line: "There was no reduction in bee visit."

Such statements indicate the degree of casualness with which the assessment seems to have been made. Our research (recent unpublished data) at the Centre for Pollination Studies, University of Calcutta, reveals for the first time in India that there is significant pollination deficit (when the actual pollination is less than the potential pollination) in conventional mustard grown in intensive agricultural areas where extensive agro-chemicals were used. This was because of the reduction in optimum pollinator population in the landscape that would have been essential for the formation of optimum seed sets in the mustard crop.

In 2005, a major study carried out by a group of American researchers led by Iora Morandin reported a high pollination deficit in genetically modified canola fields (B napus and B rapa) compared to the organic and conventional varieties. This study clearly outlined the effect agrochemicals (including herbicides) would have on pollination. While organic canola had no pollination deficit, the conventional canola (grown with agro-chemicals) had moderate pollination deficit.

In case of the DMH-11, no such pollination deficit study was carried out by comparing it to organic mustard, conventional mustard and the genetically modified hybrid – or even available non-genetically-modified hybrid mustard varieties – across seasons, years and locations.

Further, DMH-11 has been made resistant to a herbicide called gluphosinate, and if the genetically enhanced mustard is commercially released, the farmers are sure to use it generously on the crop. However, the impact of gluphosinate on honeybee health has not been looked at. This is a gaping hole in the assessment protocol.

This is all the more worrisome because very little information is available on the impact of gluphosinate on terrestrial (or aquatic) animals. So nobody really knows what impact the herbicide will have on the bees and other non-target organisms.

Glaring loopholes

As is apparent from the Assessment of Food and Environmental Safety document, although a pollen flow study was conducted for DMH-11, there was no such study conducted for the parent gene – barnase, which comes from soil bacterium Bacillus amyloliquefaciens.

This gene causes male sterility in one parental line of the plant – suppressing its pollen production – and is therefore problematic if it escapes into the wild.

Moreover, the study has been carried out for a single season only, which is grossly inadequate. Such studies need to be carried out over several years. The studies on Bt Brinjal were also carried out over multiple seasons. The single-season study is a prime example of why the move to introduce DMH-11 is hasty.

The pollen flow study reported in the Assessment of Food and Environmental Safety document contains nothing about whether the extent and rate of outcrossing – whether the pollen grains from genetically enhanced mustard were carried by bees to other non-GM mustard varieties or closely-related plant species – was assessed at all.

It appears that the study protocol was limited by a plot distance of only 50 metres surrounding the outer boundary of genetically enhanced crop as specified in Page 85 of the Assessment of Food and Environmental Safety document.

The protocol of fixing the study radius to 50 m is similar to the one used by a group of British scientists led by Jodi Scheffler in 1993. This study was conducted on genetically engineered oil-seed rape (Brassica napus) involving European honey bees (Apismellifera) and the bumble bee (Bombusterrestris).

Although Apismellifera is found in India, the dominant honey bee species are Apiscerana (hive bee) and Apisdorsata (the Indian rock bee). The rock bee, which is larger and feistier than its European counterpart, can carry pollen grains to distances greater than 50m. Unfortunately, this possibility was conveniently forgotten.

Eco-friendly alternatives

The main reason for the aggression and haste in pushing genetically enhanced mustard seems to lie in the (independently unverified) claim that it will increase the yield of the plant by 30%.

But yield can be increased through other pollinator-friendly and eco-agricultural means.

In fact, even if DMH-11 has the potential to increase yield, the deficit in cross-pollination is likely to bring the overall output down.

Instead, yield can be increased by adopting a non-fatal pest-management systems and keeping semi-natural vegetation in the landscape. This technique could be tested on the nearly 12 improved varieties of mustard seeds, (for example, those developed in the Indian Agriculture Research Institute or the Coral 432 hybrid variety developed by Advanta).

In fact, these high-yield hybrid varieties of mustard were also overlooked while testing DMH-11 – no comparison study was carried out between DMH-11 and these varieties.

So the question then arises: do we really need genetically modified hybridisation in the first place?

This poor assessment mechanism was brought up by the environment ministry while imposing the moratorium on Bt Brinjal. The decision document of the ministry had said that “more well designed tests that are independently conducted and widely accepted” would be required before any decision on its release could be considered.

But the case with DMH-11 shows us that six years on, nothing has changed.

Dr Parthib Basu is the associate professor and HoD, Zoology, and Director of Centre for Pollination Studies, University of Calcutta