The scientists have no interest in increasing the production of tobacco; their plan is to try the same alterations in food crops, and one of the leaders of the work believes production gains of 50 percent or more may ultimately be achievable. If that prediction is borne out in further research — it could take a decade, if not longer, to know for sure — the result might be nothing less than a transformation of global agriculture.

The findings could also intensify the political struggle over genetic engineering of the food supply. Some groups oppose it, arguing that researchers are playing God by moving genes from one species to another. That argument has gained some traction with the public, in part because the benefits of gene-altered crops have so far been modest at best.

But gains of 40 or 50 percent in food production would be an entirely different matter, potentially offering enormous benefits for the world’s poorest people, many of them farmers working small plots of land in the developing world.

“We’re here because we want to alleviate poverty,” said Katherine Kahn, the officer at the Gates Foundation overseeing the grant for the Illinois research. “What is it the farmers need, and how can we help them get there?”