Release of GE American Chestnut Trees into Wild Forests Raises Serious Risks

THIRD WORLD NETWORK BIOSAFETY INFORMATION SERVICE

 

Dear Friends and Colleagues 

Release of GE American Chestnut Trees into Wild Forests Raises Serious Risks

The American chestnut, once a dominant species in eastern North American forests, was decimated in the first half of the 20th century by a fungal blight and logging. An in-depth paper describes the science and risks associated with plans to release genetically engineered (GE) blight-resistant American chestnut trees into forests. If approved, the GE American chestnut will be the first GE forest tree species planted specifically to spread freely through forests.

The GE American chestnut tree has been engineered to produce oxalate oxidase enzyme, or OxO, which does not eliminate the (blight) pathogen, but inhibits it from spreading on the tree, making it less lethal. Efforts to genetically engineer pathogen resistance, even in common agricultural crops, have been unsuccessful because pathogens evolve to overcome plant defenses, and increasing resistance to one pathogen may lead to higher susceptibility to others. In addition, the existence of other pathogens lethal to American chestnut, such as Phytophthera cinnamomi, as well as a variety of stresses including climate change, contribute further to the challenge of chestnut restoration. OxO-engineered blight resistance does not protect the American chestnut from Phytophthera.

The GE American chestnut is specifically intended to be released into forests, and to spread its GE pollen and seeds. The risks of introducing the GE American chestnut into forests are numerous and difficult to assess, and regulatory agencies are ill-equipped to evaluate a GE forest tree intended for deliberate spread through wild forests. Once it is released, there will be little potential to track or reverse its spread. GE American chestnut pollen and nuts could contaminate hybrid chestnut orchards, and spread across borders and jurisdictions.

While the GE American chestnut appears to be resistant to blight, the results are preliminary and based only on testing of young trees in controlled conditions. Extrapolation about the stability and viability of GE American chestnut over the many decades of a tree’s lifespan, and under the many diverse conditions encountered in nature is simply not possible at this time. Given the irreversibility of the release of GE American chestnut into nature; the questionable long-term effectiveness of OxO-engineered blight resistance; the unpredictable future of impacts of climate change on forests; and the serious threat of Phytophthera, which is anticipated to spread and for which there is currently no solution, the ultimate success of American chestnut restoration is highly questionable. Not only could GE American chestnut fail, it could create new problems and exacerbate existing pressures on forest ecosystems.

The paper concludes that the deregulation of GE American chestnut is clearly premature, but is being strongly promoted as a test case to sway public opinion and pave the way for the introduction of other GE trees for the commercial production of timber, pulp and biofuels. The authors call for the Precautionary Principle, which was formulated to avert harm by delaying action until safety can be proven, to be used as the appropriate framework for responding to the proposed introduction of GE American chestnut.

 

With best wishes,

Third World Network
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Email: twn@twnetwork.org
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Item 1

BIOTECHNOLOGY FOR FOREST HEALTH? THE TEST CASE OF THE GENETICALLY ENGINEERED AMERICAN CHESTNUT

The Campaign to STOP GE Trees, Biofuelwatch and Global Justice Ecology Project
April 2019
 

Executive Summary

The American chestnut, once a dominant species in eastern North American forests, was decimated in the first half of the 20th century by a fungal blight (Cryphonectria parasitica, also referred to as chestnut blight) and logging. Researchers at the State University of New York College of Environmental Science and Forestry are developing a genetically engineered (GE) blight-resistant American chestnut (AC), and hope to win government approval for its unregulated release into the environment. If they are successful, the GE AC will be the first GE forest tree species planted specifically to spread freely through forests. Once the GE AC is released, there will be little potential to track or reverse its spread.

The GE AC is promoted as a test case to sway public opinion toward supporting the use of biotechnology for forest conservation, and to pave the way for the introduction of other GE trees. However, most other GE trees in development would be grown in industrial monoculture plantations, for the commercial production of timber, pulp and biofuels. A close look at who is promoting the GE AC reveals direct and indirect financial and other links between the nonprofit The American Chestnut Foundation, the researchers developing the GE AC, tree biotechnology company ArborGen, biotechnology company Monsanto (now Bayer), Duke Energy, government agencies, and other entities including the Forest Health Initiative and the Institute of Forest Biosciences that are deeply invested in advancing the use of biotechnology for forest restoration as a public relations tool.

The GE AC tree has been engineered with an oxalate oxidase enzyme, or OxO, derived from wheat, along with other marker and promoter genes. The OxO trait does not eliminate the pathogen, but inhibits it from spreading on the tree, making it less lethal. While tests on a small number of young GE AC trees have shown some resistance to Cryphonectria, extrapolation from these results is unreliable, given the long lifespan of AC (potentially over 200 years) and the variable conditions it encounters in nature. Efforts to genetically engineer pathogen resistance, even in common agricultural crops, have been unsuccessful because pathogens evolve to overcome plant defenses, and increasing resistance to one pathogen may lead to higher susceptibility to others. In addition, the existence of other pathogens lethal to AC, such as Phytophthera cinnamomi, as well as a variety of stresses including climate change, contribute further to the challenge of chestnut restoration, with or without genetic engineering.

The GE AC is specifically intended to be released into forests, and to spread its GE pollen and seeds. Locating and monitoring all GE AC trees and their progeny will be nearly impossible, especially over a long period of time. GE AC pollen and nuts could contaminate hybrid chestnut orchards, and spread across borders and jurisdictions. Researchers claim that a robust regulatory process will be sufficient to address risks. However, the U.S. regulatory system has no specific regulations to deal with the release of GE trees into forests. In addition, our minimal knowledge about highly complex forest ecosystems and the potential impacts of climate change make adequate risk assessments impossible. Other concerns include the safety of eating GE AC nuts or inhaling GE AC pollen, and impacts on wildlife, pollinators, other plants, soils and waterways.

The development of GE trees has been met with strong and ongoing public opposition including from scientists, foresters, and ecologists. Indigenous Peoples whose traditional lands fall in the range of AC have expressed concern about the impacts on their territorial sovereignty and right to keep GMOs off their lands.

The release of GE AC into forests would be a massive and irreversible experiment. The introduction of GE AC could not only fail, but also create new problems and exacerbate existing pressures on forest ecosystems. Forests are already threatened by unsustainable logging practices, invasive species and introduced pests and pathogens, urban sprawl, and the escalating impacts of climate change. Without solving these underlying causes of forest demise, the restoration of the American chestnut through any technology is highly improbable.

Decisions about the introduction of the GE AC will set a regulatory precedent and set the stage for the future of forest genetics. The GE AC should not be permitted for distribution. The UN Convention on Biological Diversity and forest certification regimes including the Forest Stewardship Council and Sustainable Forestry Initiative call for application of the precautionary principle to GE trees, with the FSC and SFI banning their use. The precautionary principle, which was formulated to avert harm by delaying action until safety can be proven, is the appropriate framework to apply to decision-making related to the GE AC.

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Item 2

THE GE AMERICAN CHESTNUT – RESTORATION OF A BELOVED SPECIES OR TROJAN HORSE FOR TREE BIOTECHNOLOGY?

Independent Science News, June 11, 2019

https://www.independentsciencenews.org/environment/the-ge-american-chestnut-restoration-of-a-beloved-species-or-trojan-horse-for-tree-biotechnology
by Rachel Smolker, Ph.D. (Biofuelwatch) and Anne Petermann (Global Justice Ecology Project)

About a century ago the American chestnut tree was attacked by the introduced fungal pathogen (Cryphonectria parasitica). This fungus drove the chestnut to functional extinction. Now, scientists at the State University of New York College of Environmental Science and Forestry (SUNY ESF) claim to have created, through biotechnology, a resistant American chestnut variety. They aim to petition the required regulatory agencies (USDA, FDA, EPA) for deregulation of their genetically engineered chestnut in the near future, with the stated goal of “restoring” the species to nature.

If it is deregulated, the GE chestnut would be the first GE forest tree species to be planted out in forests with the deliberate intention of spreading freely. Monitoring or reversing their spread, once released, would likely be impossible. Performing valid risk assessments of the potential impacts of GE American chestnut on forests, wildlife, water, soils, pollinators or people, is hampered by our lack of knowledge about both the ecology of the American chestnut and forest ecosystems. Furthermore, since American chestnuts can live for more than 200 years, risk factors may change over the tree’s lifetime in unpredictable ways.

Critically, the choices we make about the GE American chestnut will set a precedent for the future use of biotechnology on other forest tree species and even more broadly, on the use of biotechnology, including new technologies such as gene editing, gene drives etc. as “tools for conservation”.

It is therefore critical that we carefully evaluate the case of the GE American chestnut. Towards that end, we recently published “Biotechnology for Forest Health? The Test Case of the Genetically Engineered American Chestnut”.

That paper was inspired by previous experience with a 2018 National Academy of Sciences study group on “The Potential of Biotechnology to Address Forest Health”. The case for using genetically engineered American chestnut for species restoration featured within the NAS study group. Similarly, GE chestnut has also been featured in other contexts where the potential for using biotechnology in conservation has been evaluated. For example, it is presented as a “case study” in the International Union for Conservation of Nature 2019 report “Genetic Frontiers for Conservation: An assessment of synthetic biology and biodiversity conservation”. We therefore felt compelled to clearly articulate and share our reasons for opposing the GE American chestnut.

The American chestnut is a much beloved, iconic, “perfect tree” – that once was a dominant species along the eastern USA and into Canada. Prolific nuts reliably provided nutritious and delicious food, and fodder for livestock. The wood, rot resistant, easy to work with and pleasing to the eye was prized by the timber industry. Cryphonectria, “the blight” was a catastrophe – for the forests and wildlife, and for the human economies, especially those of rural Appalachia, where the seasonal nut harvest was key source of income, and sustenance. Restoring the American chestnut is a long-held dream for some people, even as our collective memory of chestnut-filled forests grows dim with the passage of time.

The American Chestnut Foundation has worked to implement a breeding program that would hybridize American chestnut with the naturally blight resistant Asian chestnut, and then backcross to produce a blight resistance tree that nonetheless preserved the growth characteristics of the American chestnut. Hundreds of thousands of hours of painstaking work across many years has gone into this breeding program – a long process that has slowly progressed, albeit with some setbacks along the way.

The SUNY ESF scientists claim that genetic engineering will provide a faster solution. After experimenting with various genes and combinations of genes, they have settled on using a gene sequence derived from wheat that causes the tree to produce an enzyme, oxalate oxidase, (aka OxO) (Nelson et al., 2014). This enzyme inhibits the spread of the fungus once established, making it less lethal to the tree. OxO is not uncommon in nature, and has been experimented with in a variety of common crops. In their promotional materials, the scientists are careful to highlight that OxO is common, and that the gene comes from ordinary wheat – conjuring images of saving the chestnut with nothing more dangerous than a tasty slice of buttered toast.

But will the OxO trait really enable restoration of the species? This is highly unlikely. First of all, engineering resistance to fungal pathogens in general has proven extremely challenging. Biotechnologists have long struggled to do so with familiar common crops with which, unlike forest tree species, we have plenty of prior experience. In spite of many, many efforts, only a single fungal pathogen resistant crop is commercially available (the Simplot potato, resistant to late blight). The problem is that fungi are very good at finding new ways to evade plant defenses. There is a virtual arms race going on between plants, evolving new defenses, and fungal pathogens, evolving new ways around those defenses. Hence making durable effective resistance is extremely difficult. As well, when plants invest in defending against a pathogen, their growth is often stunted or otherwise compromised and they can become more susceptible to other pathogens or stresses they encounter (Collinge et al., 2010).

SUNY ESF’s OxO engineered chestnut trees appear to be resistant to the blight – but only young trees in controlled lab and field trial conditions have been tested. The oldest trees tested to date are only about 15 years old – other more recently developed lines are even younger. Yet chestnuts can live for over two hundred years during which time they may experience many diverse conditions – weather extremes, insects and pathogens etc. that could affect the expression of the OxO trait, or other characteristics of the trees. We cannot reasonably assume long term durable blight resistance in natural forests based on extrapolation from results on very young trees under controlled and laboratory conditions.

Even the SUNY scientist most involved with developing the OxO engineered chestnuts, William Powell, openly acknowledges that long term stable resistance to Cryphonectria, based on the OxO trait alone, is unlikely to succeed. He states:Eventually we hope to fortify American chestnuts with many different genes that confer resistance in distinct ways. Then, even if the fungus evolves new weapons against one of the engineered defenses, the trees will not be helpless.”

Another pathogen, Phytophthora cinnamomi, (aka root rot or ink disease) had been killing off American chestnuts in the southern part of their range even before Cryphonectria arrived. That pathogen is meanwhile spreading northwards under a warming climate. Scientists agree that restoration of the chestnut would require stacking of multiple traits including for resistance to Phytophthora. The OxO trait alone will not restore American chestnuts.

So why claim otherwise? Why rush the GE chestnut into regulatory review when even its’ own creators recognize it cannot fulfill the goal of species restoration? Because the OxO engineered chestnut – using “nothing but a wheat gene” to “restore a beloved iconic species” is being used as a public relations tool for winning over public opinion toward GE trees more generally, and for the use of biotechnology as a “tool of conservation”. This is a strategy that biotechnology industry proponents expect will soften public opposition and open up the potential for commercializing a wide array of GE trees.

The GE American chestnut is in fact very explicitly referred to in terms of its’ value for public relations, and as a “test case”. For example, Maud Hinchee, former chief technology officer at tree biotechnology company, ArborGen, and formerly from Monsanto, states:We like to support projects that we think might not have commercial value but have huge value to society, like rescuing the chestnut. It allows the public to see the use of the technology and understand the benefits and risks in something they care about. Chestnuts are a noble cause.”

Scott Wallinger of paper company MeadWestvaco (now Westrock) stated back in 2005: “This pathway [promoting the GE chestnut as forest restoration] can begin to provide the public with a much more personal sense of the value of forest biotechnology and receptivity to other aspects of genetic engineering.”

The Forest Health Initiative which funds the SUNY ESF GE chestnut project states their aim is toadvance the country’s understanding and the role of biotechnology to address some of today’s most pressing forest health challenges. The initiative will initially focus on a “test species” and an icon of eastern US forests–the American chestnut.” And even the American Chestnut Foundation states: “If SUNY ESF is successful in obtaining regulatory approval for its transgenic blight resistant American chestnut trees, then that would pave the way for broader use of transgenic trees in the landscape.

What “broader use of transgenic trees” can we foresee? A review of the literature on forest biotechnology reveals that most tree biotechnology research is focused not on addressing “forest health” for the public good, but on ways to engineer trees for commercial and industrial processes and profitability. A review of forest biotechnology published in 2018 states: “Genetic engineering of trees to improve productivity, wood quality and resistance to biotic and abiotic stresses has been the primary goal of the forest biotechnology community for decades… Examples include novel methods for lignin modification, solutions for long-standing problems related to pathogen resistance, modifications to flowering onset and fertility and drought and freeze tolerance.” (Chang et al., 2018).

Most efforts to address “forest health” are focused on species of commercial interest, which are often grown in industrial monoculture plantations, and therefore more vulnerable to a variety of pests, pathogens and health threats.

For example, there has been considerable research focussed on engineering resistance to insect pests in commercially important species such as pine, poplar and eucalyptus (Balestrazzi et al., 2006).

Meanwhile with increasing awareness of the dangers inherent to using fossil fuels, burning wood instead of, or in addition to coal is heavily subsidized (alongside solar panels and wind turbines) as renewable energy, and falsely accounted as “carbon neutral”. Efforts to convert wood into liquid transportation fuels have so far largely failed to attain commercial scale in spite of massive investments. Turning trees into biofuels, bioplastics etc. largely depends not only on genetically engineering specific characteristics into the trees, but also on engineering microbes that produce enzymes needed to break down, access and ferment the sugars in wood. A 2017 review, titled “Biotechnology for bioenergy dedicated trees: meeting future energy needs” points to eucalyptus, pine, poplar and willow as the species of most commercial interest, with biotechnology research focused on enhanced growth and yield, altered wood properties, side adaptability and stress tolerance, and the alteration of lignin, cellulose and hemicellulose for effective biorefinery conversion to cellulosic biofuels (Al-Ahmad, 2018).

In sum, there is much riding on winning over public opinion on GE trees.

This is why such entities as Duke Energy, ArborGen and Monsanto, as well as various multinational timber corporations, are among those funding or promoting the GE chestnut. The Forest Health Initiative, which receives funding from some of the above, and in turn has provided large grants to the SUNY ESF research, states:Biotech trees will find their place in this world, providing fiber, fuel, and even sustainable comfort food (e.g. biotech chestnuts roasting on an open fire). This is an industry to watch as it evolves toward responsible use and takes its place in the pipeline of sustainable biotech products.

Enthusiasm for GE American chestnuts has so far been underwhelming. Recently, board members of the Massachusetts/Rhode Island chapter of the American Chestnut Foundation, Lois Breault-Melican and her husband, Denis M. Melican, who had worked for over 16 years on backcross breeding of resistant American chestnuts, resigned in protest against the organizations’ embrace of SUNY ESF’s GE American chestnut. They stated: We are unwilling to lift a finger, donate a nickel or spend one minute of our time assisting the development of genetically engineered trees or using the American chestnut to promote biotechnology in forests as any kind of benefit to the environment. The GE American chestnut is draining the idealism and integrity from TACF.”

Indeed, public opinion has long been solidly opposed to GE trees in general, and remains a significant barrier to their release. A number of protests have taken place around the world where GE trees have been tested, including the destruction by women from social movements in Brazil including the MST (landless worker’s movement), of GE tree seedlings belonging to Futuragene in Brazil in 2016. The Campaign to Stop GE Trees was founded in 2014 and has both national and international presence.

When ArborGen sought to field test their GE eucalyptus in the U.S., several organizations filed a legal suit in 2010 challenging the planned field trials. And when the USDA issued a draft Environmental Impact Statement recommending approving deregulation of ArborGen’s GE eucalyptus in 2017, over 284,000 people signed onto or submitted their own comments opposing deregulation of the GE eucalyptus. (To date, no final EIS has been issued by USDA and the petition for deregulation appears to be languishing). Forest certification bodies including Forest Stewardship Council, the Programme for Endorsement of Forest Certification and the Sustainable Forestry Initiative have banned the use of GE trees and their products. The 2008 decision IX/5 (1) of the UN Convention on Biological Diversity Conference of the Parties from 2008 recommended a precautionary approach to GE trees.

GE tree proponents claim that regulatory processes can ensure safety, and complain that they are overly burdensome. But experience with common GE crops demonstrates that standard regulatory reviews, as exemplified by the escape and invasion of GE creeping bentgrass, do not preclude serious harms. In the case of the GE American chestnut, uncontained spread is in fact intentional. Hence there will be no way to prevent contamination of remaining pure American chestnuts, or hybrid chestnut orchards. Nor will it be possible to prevent the spread of GE chestnuts across territorial boundaries.

The GE American chestnut is meant to launch us down the slippery slope of tree biotechnology. In the wings, and waiting to follow in that newly forged path are a host of other GE forest tree species, engineered for commercial industrial purposes. Natural forests meanwhile are rapidly declining, even as climate science dictates that protecting and restoring forests is a crucial part of regaining carbon balance. Yet logging, even of the precious remaining old growth forests, continues largely unabated, often subsidized with public funding. Replacing real forests with tree plantations, and then referring to them as “planted forests”, conceals the fact that tree plantations are more akin to corn fields than forests. They often displace natural forests and rural communities, are monocultures lacking biodiversity, doused with herbicides and agrichemicals, rapidly drain fresh water sources, and are designated for fast growth and short rotation mechanical harvesting.

Debates about forest health, and the potential for biotechnology to provide solutions are irrelevant when underlying drivers of forest demise are not addressed.

If we are seriously concerned about protecting forest health, then reigning in those underlying drivers of forest destruction is the real solution – not genetically engineering trees or replacing diverse natural forests with industrial plantations.

References

Al-Ahmad, H. (2018) Biotechnology for bioenergy dedicated trees: meeting future energy demands. Z. Naturforsch. C. 73(1-2): 15-32.

Balestrazzi A., Allegro G., Confalonieri M. (2006) Genetically Modified Trees Expressing Genes for Insect Pest Resistance. In: Fladung M., Ewald D. (eds) Tree Transgenesis. Springer, Berlin, Heidelberg.

Chang, S. et al. 2018. GE of trees, progress and new horizonsIn Vitro Cellular & Developmental Biology-Plant 54:341-376.

Collinge DB, Jørgensen HJL, Lund OS, Lyngkjær MF (2010) Engineering Pathogen Resistance in Crop Plants: Current Trends and Future Prospects. Annual Review of Phytopathology 48: 269–291.

Nelson CD, Powell WA, Merkle SA, Carlson JE, Heberd FV, Islam-Faridi N, Staton ME, Georgi L. (2014) Biotechnology of Trees: Chestnut. In: Ramawat KG, Mérillon J-M, Ahuja MR (Eds), Tree Biotechnology. CRC Press, Boca Raton, FL, 3-35.

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