A wild thought: Are genetically-engineered trees really ‘the future’

As the US mulls over releasing genetically engineered trees in the wild, experts warn of its possible environmental impact

By Shuchita Jha
Published: Friday 27 January 2023

More than a century after the American chestnut tree became functionally extinct, the United States is weighing whether to allow a genetically engineered (GE) version to spread in the wild. The country has already developed and field tested the GE version, known as Darling 58, and is now awaiting clearances from government agencies to grow them in the wild.

The impending decision has unleashed a fierce debate over the promises and perils of genetic engineering that could be heard even at the recently concluded 15th Conference of the Parties (COP15) to the UN Convention on Biological Diversity (CBD) in Montreal, Canada. This despite the fact that the US is not a part of CBD, which has 196 member-states.

“If they are successful, it will be the first GE forest tree species planted specifically to spread freely through forests. Once released, there will be little potential to track or reverse its spread,” reads a white paper released at COP15 by global non-profit Action Group on Erosion, Technology and Concentration (ETC) and was signed by 87 national and international organisations from 40 countries.

The population of the American chestnut, a deciduous tree native to North America, dwindled in the first half of the 20th century when a fungal blight, Cryphonectria parasitica, killed over four billion trees. The blight is believed to have travelled to the US from the Chinese varieties of the tree.

Ever since, millions of American chestnut stumps have continued to sprout every year, but only a handful of them survive long enough to produce nuts. Most of them get re-infected with the blight and die, restarting the cycle again.

A group of researchers at the State University of New York College of Environmental Science and Forestry began experimenting with a GE blight-resistant American chestnut in the 1980s.

They finally added an enzyme from wheat that breaks down the toxin produced by the blight to develop the Darling 58 line of blight-tolerant trees. The researchers now, citing conservation of the species, hope to win the approval of the US government for the unregulated release of these GE varieties into the wild.

While the US is the only country that is considering the introduction of GE tree varieties in the wild, many others have been experimenting with GE tree varieties for commercial plantations.

In 2002, China allowed the commercial plantations of two varieties of GE insect-resistant poplar trees. According to Malaysia-based non-profit World Rainforest Movement, the country has planted about 1.4 million GE poplar trees on 300-500 hectares.

While China is the only country where commercial plantations of GE trees has started, the US, Germany and Canada are also conducting field tests for GE poplar varieties.

In 2015, the US and Brazil gave the go-ahead for commercial plantations of GE versions of loblolly pine and eucalyptus trees, but the plantations did not take off for various reasons.

In Brazil, the country’s native eucalyptus variety was found to be more productive than the two GE varieties, and in the US, the decision triggered massive protests from local communities.

According to a September 2022 study released by US-based non-profit The Campaign to Stop Genetically Engineered Trees, ArborGen, the private company that developed the loblolly pine variety in the US, has “moved on to other things”.

Even India has been experimenting with a GE variety of rubber tree for the past two decades. The Rubber Research Institute of India, a Union government research centre based in Kerala, received clearance for field trials in 2010, but had to abort its plans after the Kerala government did not allow the trials. In June 2021, the research institute under the Rubber Board got the nod from the Assam government to carry out the field trials.

The GE variety has been modified by inserting additional copies of the gene MnSOD (manganese-containing superoxide dismutase) which enables the plant to tolerate extreme climatic stress, says James Jacob, former director of the Rubber Board.

The variety will allow non-traditional rubber states such as Assam and Mizoram to cultivate better quality rubber, he adds. There are about six more GE rubber varieties, each incorporating different genes of interest or beneficial agronomic traits. They are at different stages of development in the laboratory.

Mounting opposition

The signatories to the white paper at COP15 called on member states to explicitly exclude geoengineering from the Global Biodiversity Frame-work, which was adopted at the meeting to halt the sharp and steady loss of biological species. The geoengineering ban, however, did not make it to the new framework.

While there are international treaties and protocols in place to regulate and monitor living modified organisms, which are defined as living organisms with a novel combination of genetic material obtained through the use of modern biotechnology, few countries follow them.

At COP9 of CBD in 2008, member states agreed on “the need to take a precautionary approach when addressing the issue of genetically modified trees”. Still, Brazil, which is a signatory to CBD, has approved the commercial release of two different GE eucalyptus trees.

“One of the issues being raised by ETC Group at COP15 was the need for identifying technological threats before they are implemented so that there can be some controls created, including the possibility of a moratorium,” Anne Petermann, co-founder and executive director of Global Justice Ecology Project, told Down To Earth.

GE trees pose a particularly high risk of contaminating other trees, along with the animal and insect species that rely on them. “One pine tree produces around 100 million pollen grains per day…(there are examples of) pine pollen that travelled up into the atmosphere to 610 meters and more than 41 kilometres across water to an island were still found to be viable,” says the September 2022 report.

Experts opposing the GE trees say that the American chestnut is being used as a “test case” by representatives of the timber and biotechnology industries who are using it to sway public opposition and open the door for approval of other GE tree species.

The American chestnut research has been primarily funded by big agrochemical and agricultural biotechnology companies such as Monsanto (now Bayer), Duke Energy and ArborGen.

The current research is driven by the interests of industries, even though it is being pushed as a method to address threats to forest health as a public good or preserve and restore nature.

“GE trees will be protected by patents, just like GE crops. Companies that sell GE trees will determine what conditions must be met in order to make a profit. We can assume that tree plantation companies will need to buy the rights to use these patented trees every time they need to plant new trees,” says Lucy Sharratt, coordinator of non-profit Canadian Biotechnology Action Network. Plantation companies already buy non-GE seedlings that are protected by contracts with the companies that supply seedlings, she adds.

There are also concerns over the lack of information on how a GE tree will behave as it ages. A chestnut tree survives for over 200 years and throughout its life faces many environmental conditions: drought, flood, heat, pest attacks and others.

“We cannot rely on extrapolation from test results from young trees to assume that blight resistance will be functional over a longer period and under the variable conditions of natural forests,” says the white paper.

The evolution of pathogens with time and their susceptibility to other pathogens is another concern that experts say the current research has not factored in.

Experiments conducted on GE crops show that engineering resistance to one pathogen, often leaves plants more susceptible to other pathogens or stresses, or reduces plant growth significantly. Over time pathogen resistance becomes less effective or not effective at all.

The impact of GE trees on indigenous communities is another concern put forward by experts. Large areas of forests are owned and inhabited by indigenous people and the biodiversity fuels local economies and holds cultural significance with sacred sites that form the identities of the indigenous communities. But the transgenic material from GE trees holds the potential to fundamentally reshape the shared environment.

Jacob says that GE trees are the future and government investments in the research can alone break the private sector monopoly. In India, for instance, living things cannot be patented.

But RRII can register the GM Rubber as a new plant variety as an exclusive property and RRII can have exclusive right of sale, he says. RRII, for instance, has developed several hybrid rubber tree varieties through grafting and has given them to farmers free of cost.

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This was first published in the 16-31 January, 2023 print edition of Down To Earth

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