Sections of farmers, activists, and scientists on Monday accused the Centre of misleading the Supreme Court by claiming that genetically-modified mustard is not herbicide-tolerant and that it will help reduce the country’s edible oil import bill.

The farmer groups and activists campaigning against GM crops also said government scientists had violated the Centre’s undertaking to the court by planting GM mustard in Bharatpur, Kanpur, Jhansi, Ludhiana, Sriganganagar, and Varanasi earlier this month as part of environmental release studies.

An expert panel under the Union environment ministry had in October approved the environmental release studies of the GM mustard developed by scientists at the University of Delhi South Campus.

The scientists have said GM mustard will help improve yields by 25-30 per cent and reduce the country’s edible oil import bill.

Many scientists had welcomed the approval.

Former biotechnology secretary and former principal scientific adviser to the Indian government had tweeted in October: “Mustard farmers are ready for change… higher yields without any additional input of water, fertilisers, or pesticides.”

The planting of GM mustard at the six locations by Indian Council of Agricultural Research (ICAR) scientists comes amid hearings by the Supreme Court of a petition that is opposing the release.

The Centre is attempting to mislead the Supreme Court through “untrue and incorrect statements on GM mustard” in the affidavits it has submitted by the court, Kavitha Kuruganti with the Coalition for a GM-Free India said in a media statement on Monday.

Dhiraj Singh, a crop scientist and former director of the ICAR-Directorate for Rapeseed Mustard Research, said the genetic changes in the GM mustard enhance the expression of the so-called bar gene and make it herbicide-tolerant.

“The bar gene is responsible for the herbicide resistance — saying that GM mustard is not herbicide tolerant is incorrect,” Singh said.

"They have placed it in both male and female — this will enhance the herbicide-tolerant trait manifold.”

Critics of GM mustard say the herbicide-tolerant crops would encourage farmers to spray chemical weed-killers in large amounts, increasing the residual levels of the chemicals in the crop, including in mustard leaves used in dishes such as sarson da saag.

Kuruganti said the use of chemical weed-killers would hit the poorest of women farm labourers who are routinely hired for manual de-weeding.

“We estimate that 50 per cent of Indian mustard land converted to GM mustard could affect between 50 million and 60 million person days of work,” she said.

Singh and the farmer groups have also challenged the claim by proponents of GM mustard and the Centre in its affidavit to the court that “with the increase of production of mustard due to the hybrids developed using GM technology, there would be substantial savings in foreign exchange”.

“Our existing best-performing mustard hybrids have yields higher than the GM mustard,” Singh said.

“Why don’t they compare their yield with the best-performing mustard?"

In their statement, the farmer groups and activists said the Centre had in its affidavit stated that “… the developers have nowhere claimed that yield increase is due to the three transgenes…” and also that “no such claim has been made in any of the submitted documents that the (GM mustard) outperforms non-GM hybrids”.

Alongside these statements, the argument in the affidavit that GM mustard technology would lead to "substantial savings in foreign exchange” is “utterly baseless, unscientific, and inconsistent”, the farmer groups and activists said.