Armand SeguinMore than 20 years ago, he planted his first genetically modified tree, a spruce, at a research station in northern Quebec, Canada. A few years later, hundreds of Christmas trees designed to resist the pests that kill them joined the tree. “For me, it was not something we wanted to scale, but it was a proof of concept,” he said. “We have proved that this is possible.”
Seguin, a forest genomics researcher in collaboration with the Forest Service of Canada, inserted bacterial DNA into Christmas trees that made them resistant to pine germs. Pine germs can chew tens of millions of hectares of coniferous leaves in one outbreak.
Genetically modified Christmas tree seedlings were the first genetically modified Canadian trees to be planted outdoors. They were deliberately destroyed in 2007 as part of the Seguin Research Agreement with the Canadian Forest Service.
While there is controversy in the field of genetic engineering, some scientists say the approach can be countered by creating trees that grow faster, are larger, more resistant to disease, and can even convert carbon to stable white powder that falls to the ground. Contribute to climate change; In other words, creating trees that are better at absorbing carbon from the atmosphere. “There are now solutions that can be used to genetically modify organisms to reduce chemical consumption and improve carbon sequestration, not only by improving photosynthesis, but also by making them more resistant to the environment,” Seguin said.
Lucy Sharat The Canadian Biotechnology Action Network (CBAN), which conducts research, monitoring and information on issues related to genetic engineering in food and agriculture, said some of the genetic engineering-related concerns include environmental hazards, various safety claims and public non-participation. “Fields of fast-growing trees are a big and dangerous experiment that will threaten forest ecosystems,” he said.
But the urgent challenge of climate change has made trees and forests the focus of atmospheric carbon reduction. In a report released in September, the American Foundation for Innovation and Information Technology (ITIF), which provides solutions for various areas of innovation such as biotechnology, said genetic modification of trees as carbon reservoirs could help control climate change. Wall Gadings“There are different ways in which forests can be turned into better carbon reservoirs,” said a geneticist and senior member of the foundation. “But as a first step, I suggest gene editing.”
In recent years, governments have embraced the idea of planting more trees as a way to combat climate change. The various countries of the world pledged in the Paris Agreement to keep global warming below 2 ° C (ideally up to 1.5 ° C) above pre-industrial levels and to cultivate large trees to compensate for carbon emissions. . In the run-up to Canada’s last federal election in 2019, pro-liberals Justin Trudeau They promised to plant two billion trees by 2030 to help Canada achieve zero net emissions by 2050.
The use of trees to combat climate change is based on the idea that planting more trees increases photosynthesis. Photosynthesis is the mechanism by which plants convert carbon dioxide into respirable oxygen. Carbon is converted to biomass (leaves, stems, and roots) or stored in the soil and converted into natural carbon reservoirs. But the carbon that trees store does not stay in them forever. They can return it to the atmosphere through respiration, and events such as forest fires and insect infestations cause trees to release carbon stored in their tissues during burning or decay. Efficient carbon reservoirs depend on healthy and resilient ecosystems. That’s why scientists like Seguin and Giddings say plant genetic engineering can be useful for pest resistance.
Pests that survive until spring
One of the environmental challenges posed by global warming, Giddings said, is the fact that many of the pests that usually die during the winter now survive into the spring. “Shell beetles now have better viability and are expanding their range,” he said. “If you can find ways to modify the genes of the trees in this forest to resist this pest, it would be a great advantage.”
According to a report released by the Canadian Natural Resources Agency in 2018, after fires, insect outbreaks have the second most impact on Canada’s carbon reservoirs and can destroy an ecosystem. Today, Canada is battling an epidemic of scaly beetles that dates back to the 1990s. The pine tree beetle (a species of shell beetle that lives in the United States and Canada) has since affected more than 18 million hectares of forest, according to the organization. “There are pests like mountain pine beetles that eat pine trees on the west side, as well as forest fires during droughts,” Seguin said. “Now, more than ever, we at the Canadian Forest Service have a fire expert because our forests are experiencing a lot of fires.”
Mountain pine beetles have destroyed forests around Hinton, Canada. Current efforts to control beetle outbreaks are aimed at destroying and burning infected trees by harvesting them.
Forest fires return huge amounts of carbon to the atmosphere. In 2017, the largest fire season recorded in British Columbia, about 190 million tonnes of greenhouse gases were released into the atmosphere, almost three times the province’s annual carbon footprint.
Not all trees are equal
In the world of carbon sequestration, not all trees are the same, and their age and size matter. Larger and older trees are better at storing carbon. Research shows that trees store most of their stored carbon in the last quarter of their lives, and one percent of the world’s largest trees are responsible for storing 50 percent of their forest carbon. However, reaching that point can take hundreds or even thousands of years. Giddings said there may be a genetic solution to a tree in which a gene-generated tree can grow twice as fast as normal and store twice as much carbon in half that time.
Changing plants to replace the less efficient photosynthesis process with a more efficient one, or engineering trees to convert some of the carbon they absorb into a stable white powder that the tree does not re-enter the atmosphere, are two possible solutions. That is the professor Charles Dalisi He refers to them from the Department of Biomedical Engineering at Boston University. On climate change, he said, biotechnology solutions to reduce carbon are useless when many ecosystems are reaching critical junctions. “We are at a point where it does not matter what we do in other cases,” Delisi said. “We have to get carbon out of the atmosphere.”
Engineering trees that convert some of their carbon into powdered calcium carbonate may be a possible solution because the production routes are well known. Such a tree produces a solid crop that cannot be released into the atmosphere and falls to the ground and can be harvested as raw material. “If we modify the recycling phase by converting some of the carbon into a compound that is stable and cannot return to the atmosphere, we will see a tremendous impact,” Delisi said.
Canada’s forests make up about 9% of the world’s forests. Genetic engineering can turn them into better carbon reservoirs
Giddings said recent advances in genetic technology have made gene editing faster and more accurate. Many genetic solutions to climate change suggest the use of crispers, which are special pieces of DNA that scientists use as gene editing tools to accurately modify an organism’s genome without importing foreign genetic material.
Of course, accurate edits do not necessarily lead to accurate consequences. CRISPR-Cas9, for example, is considered a very useful technology for gene editing, but can cause unwanted changes in other genes. A study published earlier this year found that these off-target side effects could remove large chunks of genetic material and cause deadly genetic mutations in animals and plants.
In a 2020 report on genome editing in food and agriculture, the Canadian Biotechnology Action Network said that while published articles prove a great deal about the potential benefits of genome editing, studies that address potential environmental impacts are being phased out. The network recently said that no genetically modified trees have been licensed for use in forest protection in North America. Of course, a variety of American chestnut called Darling 58 It may soon be an exception to this rule. Researchers at New York University’s School of Environmental and Forestry have engineered the tree to fight the fire disease that has killed most of its North American counterparts.
Canada plans to reduce its emissions to zero by 2050. For scientists like Seguin, ignoring the beneficial applications of genetic engineering is an opportunity missed. “I don’t think gene editing is the whole solution, but it is part of it,” he says.