The Southeast US will soon be springing with genetically modified (GM) trees that have been tweaked to turbocharge their ability to photosynthesize. The idea is that the fast-growing trees will become even more efficient at soaking up carbon dioxide from the atmosphere and help ease the climate crisis.
The project is the brainchild of the California-based biotech company Living Carbon.
Together with Oregon State University, the start-up recently released research – which is yet to be peer-reviewed – that suggested the GM trees accumulate 53 percent more biomass than their standard counterparts, resulting in them capturing up to 27 percent more carbon dioxide.
This preprint study was carried out in a greenhouse under lab conditions, but the hybrid trees have recently had their first venture into the real world. As reported by The New York Times, a bunch of GM poplar seedlings were planted at an active timberland in southern Georgia earlier this month.
It’s believed that this was the first time GM trees have been planted in the US outside the setting of a scientific study or a commercial fruit orchard. Beyond the site in Georgia, the company also says they have signed deals with private landowners to plant their GM trees in over 1,200 hectares (3,000 acres) of forest across the Southeast US and Appalachia.
“We have surpassed the point where reducing emissions alone will be enough to rebalance our ecosystems and stabilize our planet. Now is the time for large-scale carbon removal. Our goal is to draw down 2 percent of global emissions by 2050 using approximately 13 million acres [5 million hectares] of land,” Maddie Hall, co-founder and CEO of Living Carbon, said in a statement.
“Today’s research is just the first step in demonstrating how empowering ecology, through the responsible use of biotechnology in trees, can be a scalable and viable solution to the climate crisis,” she added.
The GM trees work by making the plants' natural ability to photosynthesize more efficient. With the help of an enzyme known as RuBisCO, plants and other photosynthetic organisms can uptake inorganic carbon (CO2) from the air and fix it into sugar for them to use.
This process doesn’t always work perfectly smoothly and occasionally “faulty” sugar chains featuring oxygen molecules are formed. To undo this, the plant will undergo photorespiration, which causes the plants to release some CO2 back into the atmosphere, wasting some of the energy produced by photosynthesis.
The GM trees have been engineered to avoid the usual photorespiration process through an alternative photorespiration bypass pathway, in which the troublesome byproduct is put directly back into tree growth, thereby wasting less energy. They acquire this ability through the addition of certain genes from plants and algae, which naturally possess alternative photorespiration bypass pathways.
Genetic modification is often one of those hot-button topics that arouse suspicion and fear – and this project is no different. The Global Justice Ecology Project has released a statement against Living Carbon's plans, arguing that the long-term risks of “GE trees, their pollen, or seeds to forests, wildlife, or human health are unknown.”
Living Carbon, for their part, argues they have taken plenty of steps to reduce the risk of “unintended consequences” and believe there are plenty of safeguards in place. Whether or not this small company can create any meaningful dents in the growing climate crisis is another question.