– At the heart of Monsanto’s global research operation is a structure with a rather ordinary name. But on the fourth floor of Building GG is a room where the future of wheat may be changing.

The facility has dozens of rooms just like it. But inside this particular 10-foot by 20-foot growth chamber — whose mirrored walls and sun-bright lamps can imitate the weather of any U.S. field — is a batch of young wheat plants.

They’re part of an intensive effort to use breeding and gene manipulation to make a new kind of wheat. The plants represent several years’ worth of work aimed at creating a plant that’s resistant to a trio of herbicides. The research has the attention of supporters and critics alike.

The supporters tout the work being done at the Chesterfield Village Research Center as critical to feeding a growing global population, while the critics say the world isn’t ready for the genetic modification of a dinner table staple.

For Creve Coeur-based Monsanto, it is an expensive and time-consuming quest. It costs $150 million or more to add just one new genetic trait to a seed. Add a long development timeline — including field trials and regulatory approvals — and it could be another decade before the company is ready to put its new wheat seeds in farmers’ hands.

“People think we’re being coy about it. But we really don’t know,” said Claire Cajacob, director of the company’s wheat research.

It takes a combination of traditional breeding and genetic enhancement to mate the ideal plant with the right genetic sequences to arm it with the ability to shrug off the herbicides dicamba, glufosinate and glyphosate — Monsanto’s signature weedkiller sold as Roundup.

To get there, researchers will sift through hundreds of thousands of plants. “You have to find the one plant that’s going to be the parent of every other seed out there,” Cajacob said.

This isn’t the first time Monsanto has sought the perfect wheat plant. A decade ago, the agriculture giant was on the verge of seeking regulatory approval for a Roundup-Ready version of hard red spring wheat, typically used for bread flour.

But in May 2004, Monsanto halted the program. It was clear that growers — worried about consumer backlash — weren’t ready.

“There was massive opposition,” said Bill Freese, a GMO critic and science policy analyst for the Center for Food Safety.

It didn’t take long, however, before wheat farmers grew tired of watching neighbors switch to more profitable corn and soybeans — both having seen greater yield increases fueled by stronger breeding programs and genetic modifications. By 2006, the number of U.S. acres planted with wheat had dropped to 57 million, down from 75 million a decade earlier. Soybeans, on the other hand, surged from 64 million to 75 million in the same period, said the U.S. Department of Agriculture.

“We came to the conclusion that we had to do something,” said Paul Penner, president of the National Association of Wheat Growers. “It’s no fun raising wheat if you are making a loss on it.”

So in 2008, the group asked its members if they were ready for GMO wheat. A survey went to 21,000 growers in the organization. A third of them answered, with 76 percent saying yes.

The change of heart should not be surprising, said Jason Lusk, an agriculture professor at Oklahoma State University and a supporter of GMO wheat. “They can see some of the benefits that other groups have enjoyed,” Lusk said. “Why deny producers the choice?”

With many wheat growers now clamoring for the same seed enhancements enjoyed by soybean and corn farmers, Monsanto changed course.

In the summer of 2009, the company revived its wheat program and grabbed the raw seed materials needed by its scientists, spending $45 million on WestBred, a Montana wheat breeding company.

In late 2013, a scare went through the global wheat market after an Oregon farmer found a rogue GMO wheat plant growing in one of his fields. This was a dozen years after Monsanto ended its testing in that state.

The discovery of that single plant sent shock waves through the industry, with several key overseas buyers — including Japan and South Korea — suspending purchases of U.S. wheat, over fears of contamination. It offered a reminder that GMO wheat still faces hurdles beyond those encountered by other crops.

The reason is simple: Corn, soybeans and cotton aren’t generally considered food. With obvious exceptions, those crops are mostly eaten by animals or turned into fuel or clothing. But wheat is bread, pasta and pastries.

It’s what makes Kyle Brase, a fifth generation Edwardsville farmer, question the wisdom of pursuing GMO wheat at this time. Brase, whose family works 3,000 acres, isn’t opposed to GMOs for most crops. But wheat is different.

“So much of it goes right into the food chain,” he said. “We really need to have the vast majority of the consumers on board before we bring it to market.”

But some agriculture observers say growing demand may eventually force the market, and consumers, to accept modified wheat because of its promise of greater yields. Jeff McPike, a grain broker with McDonald and Pelz in Boulder, Colo., said, “Five to 10 years from now, we are going to have to make that choice, or change our diets.”