Engineered microbes halve corn's fertilizer needs in trials

A dozen startups are testing engineered microbes that could slash the global need for synthetic fertilizer by feeding crops nitrogen directly from the soil.

The push comes as climate goals collide with food security. Synthetic nitrogen fertilizers account for roughly two percent of the world’s greenhouse-gas emissions and demand vast amounts of natural gas. With populations still rising and arable land shrinking, farmers face pressure to cut emissions without sacrificing yields. Early field trials by Pivot Bio, Kula Bio and others show microbes that colonize roots can supply up to half of a corn plant’s nitrogen needs, trimming fertilizer bills and emissions.

Behind the trend is a decade of cheap DNA sequencing and CRISPR edits that let scientists tune microbes for specific crops and climates. Pivot Bio’s product, for example, is a strain of *Bacillus* tweaked to excrete nitrogen continuously rather than only when triggered by rain. Field data from 2023 show average yield gains of 5 bushels per acre on corn while reducing synthetic nitrogen use by a third. Kula Bio’s pilot in Iowa last spring delivered similar results on soybeans, cutting fertilizer bills by about $30 an acre. Regulators in the U.S. and EU have so far classified these microbes as low-risk, speeding approvals.

What happens next hinges on scale. The startups are racing to produce enough microbes at farm-grade prices—currently around $10 to $15 per acre—before fertilizer prices spike again. If they succeed, the technology could reach 20 million U.S. corn and wheat acres by 2027, cutting national nitrogen fertilizer emissions by roughly 6 million tons a year. Longer term, researchers are eyeing tropical crops like rice and cassava where synthetic fertilizer use is rising fastest. Farmers will still need some synthetic nitrogen, but a managed shift to living fertilizers could reshape the trillion-dollar global food chain within a decade.