If humanity is to stage a last minute comeback and avert catastrophic climate change of a more than 2C rise in average pre-industrialisation global temperatures, the strategy will almost certainly be multi-faceted. There will be no single ‘silver bullet’ that will undo the decades of pumping harmful emissions into the Earth’s atmosphere.
But scientists at California’s Salk Institute, founded in the 1960s as a research institute pursuing cures to diseases such as polio and Alzheimer’s, do think that they are working on something with the potential to make a telling contribution – a CO2-trapping ‘superplant’.
Ideal Plant is a research project currently being conducted at the Salk Institute and led by Joanne Chory, the internationally renowned plant biologist. Ideal Plant’s mission is to bio-engineer plants that suck CO2 out of the atmosphere in much higher quantities than normal, storing it underground in their roots.
Source: The Salk Institute
In effect, much of what the scientists involved in the Ideal Plant project are trying to achieve is simply a ‘tweak’ to what plants already do naturally. Plants already use CO2 as their main food source, sucking it out of the air and converting it into sugars through photosynthesis, which uses sunlight for energy. The oxygen released back into the atmosphere is the by-product of that process.
The problem is that plants return most the of CO2 they have sequestered throughout their lifespan back into the atmosphere as they decompose. Or are burnt – like wood. Just a small amount remains in the soil. There’s an annual carbon cycle as CO2 is sucked in by growing plants in spring and then re-released in the autumn and winter as leaves fall and decay. The challenge of the Ideal Plant team has been to find a way to keep much more of that CO2 in the ground.
The secret is thought to lie in cork. Cork is actually a molecule called ‘suberin’ that all plants produce. It regulates what their roots absorb, such as oxygen and nutrients such as minerals. And it doesn’t decay. Some plants, like the cork tree, naturally produce more suberin than others.
The team have now found a gene which controls the amount of suberin a plant produces. They are also working on plants which develop larger, deeper root systems that would hold more CO2 and decay more slowly. The theory is if it is possible to use modern biotechnology engineering to adapt crop plants to produce more suberin and/or more extensive root systems and they are planted in mass around the world it could make a telling contribution to atmospheric CO2 levels.
While reducing emissions is still key to keeping temperatures from rising another 0.5% to 1% over the coming decades, technologies which tackle the problem from the other side – removing CO2 from the atmosphere, could also make a telling contribution. If the initial promise displayed by the Ideal Plant research is realised, Dr Chory and her team may be on the verge of one of the most significant breakthroughs in the fight against climate change.