Multinational biotechnology giant Monsanto Co. is bringing a small chunk of its highly influential — and controversial — seed operation to Pima County.

The company hopes to start building a facility later this year to grow corn and soybeans in at least one greenhouse on a 7-acre site in Pima County, a Monsanto spokeswoman told the Star Friday.

The main purpose will be for corn-breeding operations, which use few genetically modified organisms, Monsanto spokeswoman Christi Dixon said. But it also will do “trait integration,” which combines genetic and biotech traits, Dixon said.

Word of Monsanto’s Arizona plans became public Wednesday when the company announced in a news release “its investment plans for greenhouses in Arizona.” Dixon provided more details Friday, but didn’t specify where the greenhouse would be built. More than one greenhouse could be built on the same site, she said.

Using new automated greenhouses, with robots watering and otherwise maintaining crops, the company hopes it can “better manage risks — like insect, disease and weather variables — we may otherwise encounter in open field environments,” Dixon said in an email.

The use of “support protected culture capabilities” — indoor growing — will “increase the long-term rate of genetic gain in both corn and soybeans,” she said.

The company picked Arizona because, while greenhouses can grow things year-round in most places by blocking out the elements, “It’s easier in this kind of weather,” Dixon said, referring to Tucson’s mild winters and warm weather the rest of the year.

Local farmers aware

Monsanto’s plans for Pima County are common knowledge in the local farming community, said Arnold Burruel, a longtime Marana farmer.

He has sold GMO-based seeds to Monsanto but hasn’t talked to company officials about this venture, said Burruel, who said he’s grown GMO and non-GMO cotton as well as GMO corn and non-GMO alfalfa in his fields.

Herb Kai, an owner of the Kai Farms in Marana, said his company’s officials have talked with Monsanto about possibly selling the company land for the operation, but can’t say more because of a confidentiality agreement the two parties have signed.

“I’m sure they’re probably talking to other landowners in Arizona besides us,” said Kai, a Marana Town Council member.

GMO, herbicide controversy

The St. Louis-based company is the world’s largest manufacturer of genetically manufactured seed products for fruits, vegetables, cotton, corn and oilseeds. It calls itself “a sustainable agriculture company” that delivers products supporting farmers around the world.

It’s also been called one of the world’s most-hated companies because of its work with GMO seeds and crops, its production of the widely used herbicide Roundup and its past production of toxic chemicals such as polychlorinated biphenyls, or PCBs, a long-banned compound that was once regularly used in electrical transformers.

It’s also fought legal battles with some farmers who accused Monsanto of trying to monopolize control of seed production.

Roundup, in particular, has become hugely controversial. Last year, the International Agency for Research on Cancer, an arm of the World Health Organization, concluded that glyphosate, Roundup’s active ingredient, probably causes cancer in humans.

Monsanto has challenged that finding. The U.S. Environmental Protection Agency has long considered Roundup safe, but is now revisiting that conclusion.

On its website, Monsanto says, “We are focused on empowering farmers — large and small — to produce more from their land while conserving more of our world’s natural resources such as water and energy.

“We do this with our leading seed brands in crops like corn, cotton, oilseeds and fruits and vegetables. We also produce leading in-the-seed trait technologies for farmers, which are aimed at protecting their yield, supporting their on-farm efficiency and reducing their on-farm costs. We strive to make our products available to farmers throughout the world by broadly licensing our seed and trait technologies to other companies.”

In October, environmental, farming, food, anti-GMO and other groups will hold a mock trial in the Hague, Netherlands, to assess what they see as the company’s negative impacts. Those include pollution, accelerated biodiversity loss and “massive” production of greenhouse gases that cause climate change. The group also accuses Monsanto of crimes against nature and humanity and “ecocide.”

Writing critically about this effort, Fortune Magazine journalist Marc Gunther quoted Monsanto CEO Hugh Grant as saying U.S. corn farmers generate yields of 150 to 160 bushels an acre, far more than what’s generated in Mexico, India and Africa, where the range is 20 to about 100 bushels per acre.

“I wonder what, exactly, the anti-GMO forces who are going to spend their time and money to put Monsanto ‘on trial’ intend to do for farmers in Africa,” Grant wrote in a blog post late last year. “Like all companies, Monsanto has made mistakes. Perhaps more than its share. But I honestly don’t understand why this company is so maligned.”

Marana farmer Burruel said his use of genetically modified seed to grow crops has been “nothing but a win for us.” He says Monsanto’s greenhouse-grown seeds will probably use less water than outside field crops because it will be far easier to recycle it inside the greenhouse, where the water will be contained and won’t run off into the soil.

Because GMO crops are insect-resistant, use of chemicals on Burruel’s farm is down 95 percent, he said. That includes less use of residual herbicides on neighboring weeds that can seep into the underground aquifer.

Contact reporter Tony Davis at tdavis@tucson.com or 806-7746.