We all (I should hope, the state of the schools being what they are) know about photosynthesis. This is the process by which plants use the energy of sunlight to take carbon molecules from carbon dioxide (CO2) and run it through what biologists know of as the Calvin Cycle to produce adenosine triphosphate (ATP), which can then be combined to form sugars and carbohydrates. Simply put, photosynthesis uses the energy of the sun, hydrogen from water, and carbon from CO2 to make food. That's why plants are called "producers" as opposed to animals, including humans, who are "consumers."
Now, I told you that so I could tell you this: Not only is CO2 necessary for plant growth and therefore for the existence of life on Earth, but a slight increase of CO2 can and does have a "greening" effect - and now we read that a slight genetic tweak in some grain crops can take advantage of increased CO2 levels to increase yields - by as much as a fifth.
Developing more efficient forms of Rubisco, or engineering CO2 concentrating mechanisms into C3 crops to competitively repress oxygenation, are major endeavors, which could hugely increase photosynthetic productivity (≥ 60%). New technologies are bringing this closer, but improvements remain in the discovery phase and have not been reduced to practice. A simpler shorter-term strategy that could fill this time gap, but with smaller productivity increases (c. 10%) is to increase leaf Rubisco content. This has been demonstrated in initial field trials, improving the productivity of C3 and C4 crops. Combining three-dimensional leaf canopies with metabolic models infers that a 20% increase in Rubisco increases canopy photosynthesis by 14% in sugarcane (C4) and 9% in soybean (C3). This is consistent with observed productivity increases in rice, maize, sorghum and sugarcane.
OK, that's a lot of science talk; fortunately, the linked article also puts it in layman's terms:
A simple change to maize, sorghum and sugarcane that allows them to take advantage of rising CO2 levels can boost their growth by around a fifth.
The growth of maize, sugarcane and sorghum has been greatly boosted by modifying the plants to take advantage of higher carbon dioxide levels now found in the air.
This was done by simply increasing the activity of two genes, says Coralie Salesse-Smith at the University of Illinois. The finding should lead to the creation of new varieties whose yields go up as CO2 levels continue to rise.
Here's why this matters.
See Related: What If More Carbon Dioxide Was Actually Good for the Earth?
Climate Activism Is Under Fire Across the Globe—Will the Push-Back Make a Difference?
Cries of falling skies from climate scolds notwithstanding, a slight warming of the climate can have many benefits, not the least of which are agricultural. Here in Alaska, the warming has opened up all manner of new agricultural possibilities, to the point where the state government is actually planning a new state agricultural department to help grow Alaskan farming - and if you saw what we pay for winter tomatoes and the like, you'd see the advantage of more local crops. The genetic tweaks in some key crops described above could make a big difference as well; maize (that's corn for people who live in a country that has sent men to the Moon), sorghum, soybeans, and sugar cane are key crops in many places around the world. A slight warming will increase the viable areas for these and other crops; increasing their uptake of CO2 will not only increase yield but hey, it will remove more CO2 from the atmosphere!
The earth's climate is, as I've said many, many times, enormously complex, chaotic, and vast on a scale that's difficult for humans to comprehend. It's also self-correcting to a certain extent. Increased CO2, for example, leads to increased forest coverage, and forests can serve as big carbon sinks. But what humans can do, as seen here, is manage our own food crops and take advantage of those huge, complex, and chaotic cycles. That's what this work does. That's how agricultural sciences should work; not giving in to climate scolds and worrying about cow flatulence, but finding ways to tailor our crops to take advantage of changes in the climate - the better to feed people.
Now, with all that said, it's great to muse about how this could change world hunger. That's always a worthy goal, but a cautionary note is in order; much of the actual hunger in the world is not a problem of production, it's a problem of distribution, and it's a problem of corrupt Third World governments. Look at the areas of the world where there are problems with hunger, even famines, and then overlay that with a map of countries ruled by corrupt governments, and you'll see a lot of overlap.
But that's a story for another time.
