The weeds that could save the world

By Faye Saulsbury

Arabidopsis thaliana is as sensitive to daylight hour variations as a student with self-diagnosed seasonal affective disorder. Arabidopsis thaliana may prove to be a key player in the fight against climate change. Arabidopsis thaliana is a weed.

Research into this unlikely ally is taking place at the Salk Institute for Biological Studies in California. Outside the windows of the research centre, smoke-blackened skies serve as a menacing reminder of the importance of this work. 

Led by Joanne Chory, scientists are using gene editing techniques to bulk up Arabidopsis thaliana’s root systems. The idea is that chunky, more extensive root systems will be able to remove greater amounts of CO₂ from the air. 

Smoke-blackened skies serve as a reminder of the importance of this work

Although current trials only involve Arabidopsis thaliana, Chory’s team hopes to replicate this same carbon-sucking quality in wheat, corn, rice, rapeseed and cotton – crops which already occupy half of Earth’s arable land. If this can be achieved, then the benefits of this gene editing technique will be seen without any further land clearance.

It is generally accepted amongst the scientific community that the reduction of fossil fuels alone will not be enough to halt climate change. To achieve the goal of the 2016 Paris Climate Agreement – to keep global temperatures from rising more than 2°C above preindustrial levels – not only must we stop emitting CO₂ but we must also actively remove it.

Chory’s team is not creating a new technology; they are optimising one that already exists

Unfortunately, carbon removal technology is burdened by large land requirements for costly chemical reactors and storage facilities. Despite US Congress dedicating $60 million to carbon removal technology in 2019, current models remain too energy-intensive to be a realistic option.

Considering that many renewable energy technologies are still in their infant stages and are relatively expensive, producing yet more energy is not a realistic option in the fight against climate change. 

That is why enhancing the natural ability of plants to remove carbon dioxide from the air is such an exciting – and relatively simple – alternative. Chory’s team is not creating a new technology; they are optimising one that already exists. The answer was hidden in plain sight. 

Such innovation is vital to solving humanity’s greatest modern-day problems

Chory has spent 30 years decoding the molecular structures and mechanisms that allow plants to photosynthesise. It is through photosynthesis that plants are able to absorb CO₂ from the atmosphere and convert it into oxygen and biomass. 

The magic ingredient in this research is suberin, a molecule found in plant cell walls. Suberin is carbon-rich, impermeable to water, and does not break down easily. This last point is crucial because the process of decomposition releases carbon back into the atmosphere. 

Not only will these genetically engineered plants remove more CO₂ from the air, but enhanced carbon levels in the soil will also make the soil richer, thus promoting better crop yields. 

Engineering crops to capture and store an optimum amount of carbon dioxide, and also to increase yields for a ballooning world population, is certainly impressive. But it is also timely; such innovation is vital to solving two of humanity’s greatest modern-day problems. 

“Our greatest responsibility is to be good ancestors”

For her work, Joanne Chory has received the 2020 Pearl Meister Greengard Prize – Rockefeller’s preeminent award recognising outstanding women in science. Leading seed distributors such as Monstanto Co. are already buying rights to her idea. However, they will still need to overcome consumer resistance to genetically engineered crops.

The Salk Institute for Biological studies was founded in 1960, by the developer of the polio vaccine, Jonas Salk. His vision was to create a culture in which scientific research for the benefit of all humanity could be pursued. 

Salk believed that “our greatest responsibility is to be good ancestors.” If Joanne Chory and her team are successful, then to future generations they will be.  

Image: Triffie Axworthy