We're running out of time to prevent the world from starving

Sean Kane, Tech Insider Yahoo News 1 Apr 16;

Humans need to figure out how to grow more food in the future, and we need to do it today.

Two-thirds of humanity's calories come from four crops: corn, rice, wheat, and soy beans. And by 2050, we'll need to produce 60-110% more of these crops to account for rising population, meat and dairy consumption, and biofuel use.

And according to a worrisome new study, published the journal Proceedings of the Royal Society B study, our current methods are not going to cut it.

We've figured out to greatly ramp up food production before, so there is some cause for hope. The Green Revolution of the mid 20th century, for example, is credited with saving as many as a billion people in the developing world from starving. That happened thanks to new farming technologies, like improved irrigation, the advent of pesticides, and breeding higher-yield varieties of grains.

Further agriculture breakthroughs could help us here, but there's a huge hang-up: These improvements take decades to actually get into the ground.

"We have to start increasing production now, faster than we ever have," Stephen P. Long, a University of Illinois crop scientist and an author of the study, said in a press release. "Any innovation we make today won't be ready to go into farmers' fields for at least 20 years, because we'll need time for testing, product development, and approval by government agencies."

By that estimate, we'll have about 10 years to close the gap. "[W]e're one crop breeding cycle away from starvation," Long said.

We also may have reached a plant productivity ceiling, and it's an unfortunate consequence of the Green Revolution's success. The study claims that the fraction of plants that can be used for food is nearing its limit.

One thing hasn't changed much in agricultural technology, and might be the key to cracking the productivity ceiling, is the rate of photosynthesis.

Plants rely on this process to transform the sun's energy and carbon dioxide (CO2) in the air into food. Even though food yields have increased, photosynthesis rate within the plants has not followed suit.

myanmar rice farmingAP Photo/Richard Vogel

One major factor in photosynthesis rate in crops like rice and soy is the enzyme rubisco, which traps CO2 during the process. This trapping is known as carbon fixing, and it's responsible for creating the carbohydrates we derive energy from and, in the case of livestock, also the energy our food uses, too.

Under certain conditions, like high temperatures, "rubisco can make a mistake and use oxygen instead of CO2," Long said in the release. "When it uses oxygen, it actually ends up releasing CO2 back into the atmosphere."

That's why Long and others are trying to hack rubisco to work under high CO2 levels as well as high temperatures — and possibly use our warmer, more carbon-rich climate change to our advantage.

It's not that easy, though. A molecule called RuBP, which accepts the CO2 that rubisco traps, also affects photosynthesis. So in addition to tweaking rubisco the scientists also need to figure out how to increase the rate at which plants regenerate RuBP and handle all that extra CO2.

The team says it's already made some progress in tobacco plants by coaxing the leaves to increase carbohydrate production in the presence of both high CO2 levels and temperature — and without the use of extra fertilizer. Next up is testing the process on stable food crops.

While this may be good news for food security, the authors' forecast of the future is rather blunt.

"In the face of the extraordinary challenges ahead, we simply do not have the luxury to rule out the use of any technology that may hold promise to improve crop performance," Long said in the release.