Let's Talk About Genetically Modified Trees And The Climate Crises

 

Greening the land with new forests that capture and store more carbon and lock it in the soil, is an objective that everyone can agree on.

Planting trees represents one of the most effective, affordable and attainable means of tackling anthropogenic climate change, since these living solar collectors already capture billions of tons of carbon dioxide each year from the atmosphere through photosynthesis. About half of that carbon winds up in roots and eventually the soil, where it can stay for hundreds to thousands of years.

But what if we could create plants and soils that are even better at capturing carbon ?          

Forest trees are an invaluable commodity, providing fiber, energy, materials and climate buffering to the global community, and CRISPR (a revolutionary new molecular biology toolset that allows scientists to make rapid and precise edits to the DNA code that underpins all life) has the potential to further enhance these important traits.

Now scientists are creating fast-growing genetically modified ‘Supertrees’, with CRISPR genome editing  that can grow faster and rapidly soak up atmospheric carbon dioxide and can also be used to address the climate crisis.

CRISPR can play a role in limiting agricultural emissions, making crops more resilient to a more variable and extreme climate, and using crops and soil microbes to store more and stabilize carbon.

What are GM trees?,

As Wikipedia says- A genetically modified tree (GMt, GM tree, genetically engineered tree, GE tree or transgenic tree) is a tree whose DNA has been modified using genetic engineering techniques.

The goal is typically to give the plant a new characteristic that does not develop naturally in the species. Examples in food crops include resistance to specific pests, illnesses, environmental factors, a decrease in spoilage, resistance to chemical treatments, or a better crop's nutrient profile. Examples of non-food crops used for bioremediation for the production of pharmaceuticals, biofuels, and other products with industrial use.

Why we need genetic alteration of trees and plants,

We all know that trees take atmospheric carbon dioxide and convert it into oxygen and carbon through photosynthesis. They then release oxygen into the air we breathe and store carbon in their leaves, roots and trunk.

But natural carbon storage is not permanent. Deforestation and wildfires can release it back into the atmosphere. Even insect infestations can cause forests to decompose and release carbon.

Similarly, when it comes to carbon sequestration, the age and size of a tree also matter. The carbon absorption rate accelerates as the tree ages. The largest 1% of trees house 50% of the carbon trapped in trees worldwide. But it could take hundreds or even thousands of years for a new tree to reach that age and size.

Now, scientists use genetic engineering to accelerate their growth rate in just half the time; thereby they can reach “old growth” status in just 20 to 50 years and absorb more carbon in less time. Additionally, carbon stored in roots is trapped beneath the soil even if the tree is chopped down, dies, or burns. Trees enhanced with extra-deep roots could stow away more carbon. If we are to reach net zero carbon by 2030 then we need to be planting 150 million trees every year.

San Francisco-based biotechnology firm Living Carbon has developed a technique to genetically modify trees that can grow 1.5 times faster than unmodified trees and store more carbon.

Poplar trees genetically engineered to fight climate change start their lives in a San Francisco lab. (LIVING CARBON)

"If we were to double the acreage that we have today up until 2030, we would be able to actually plant enough trees to remove 1.66% of global emissions in 2021." CEO Maddie Hall told CNET. "That is very significant. That's the emissions of millions of people."

According to a white paper published in February, its modified poplar trees stored up to 53% more carbon than control trees. There are more than 600 Living Carbon trees currently planted in Oregon, and more projects developing on abandoned land mines in parts of Appalachia.

Benefits of gene technology of forestation,

Forests of genetically altered trees and other plants could sequester several billion tons of carbon from the atmosphere each year and so help ameliorate global warming, according to estimates published in the Jansson et al (2010).

Genetic engineering involves the manipulation of genes within a species and may also involve the transfer of genes and thus the characteristics governed by those genes from one species to another.

That is a clear-cut transfer of one or two known genes into the plant genome-a surgical alteration of a tiny part of the crop's genome compared with the sledgehammer approaches of traditional techniques, such as wide-cross hybridization or mutation breeding which bring about gross genetic changes, many of which are unknown and unpredictable. Further-more, unlike traditional varieties, modern GM crops are rigorously tested and subjected to intense regulatory scrutiny for safety prior to commercialization.

Genetically modified trees could even be programmed to transform captured carbon into a white calcium carbonate substance, which could prevent the carbon from being released again if the tree rots. This material could even be collected and used as a natural source of raw material for plastic or other durable materials.

A plant scientist at the University of Essex, UK, found that inserting some new genes into tobacco plants is over 4O percent more productive than their non-edited counterparts when it comes to carbon processing, which is vital in the fight against global warming.

Drought resistant plants and trees can also be produced by the use of genetic engineering, so that they can withstand the stressed environment.

Challenges before gene editing of trees,

GE trees are still in the research and development phase, and the science behind the genetically engineered traits has not been fully evaluated and tested.  Many questions remain while the purported benefits are unproven.

A major concern expressed about GM technology is the potential escape of genetically modified trees into the wider environment, where they might affect biodiversity and compete with wild, natural populations of the same, or related, species.

These ‘Supertrees’ have been labeled a threat to the world’s forests by environmental groups and scientists for more than 20 years. Critics point to the impact on ecosystems as large-scale commercial plantations take over from old growth forest or rainforest, targeted as carbon storage offsets for polluting industries, while biotech companies profit. Plantations are also converted to biomass and burned in power plants.

GE trees will be harder to contain than GE crops, of which there have been repeated and unavoidable contamination events, resulting in untold environmental harms and millions of dollars in economic damages. 

The current regulatory system for GE trees does not carry out comprehensive or robust risk assessments for their planting and use.

It is ill-equipped to manage contamination events should GE trees contaminate forests or cause other environmental or economic harm. 

The long term effects of GM trees on ecosystems is unknown. Whereas, there are concerns of the escape of modified genes into natural ecosystems. Rapid growth could cause shorter, more intensive rotations, resulting in greater water demand.

Genetically modified forest trees are not yet approved ("deregulated") for commercial use with the exception of insect-resistant poplar trees in China.