Growing and producing food, fiber, and biofuels generates about one-quarter of all human-caused greenhouse-gas emissions. At the same time, yields of the world’s major food crops are projected to decline in the coming decades as the climate warms, causing droughts, heat waves, or heavier-than-normal rains. In some areas it is already happening.
A group of MIT researchers hopes to tackle both sides of the problem.
Christopher Voigt, the Daniel I.C. Wang Professor in the Department of Biological Engineering and co-director of MIT’s Synthetic Biology Center, is leading a Climate Grand Challenges flagship project that aims to reduce emissions from agriculture, largely from fertilizer, and boost yields of major food crops.
So the team plans to reduce the carbon footprint of fertilizer by genetically engineering plants and soil microbes to, in effect, make their own.
The symbiotic relationship between rhizobia, a type of soil bacteria, and some legumes may offer a blueprint for developing these “self-fertilizing” plants. Rhizobia infect legumes, which provide them a home in the form of nodules in their roots. The rhizobia return the favor by converting nitrogen in the atmosphere into ammonia that is used by the plant. As a result, the plants require far less applied nitrogen fertilizer than other staple crops.
