PHILOMATH, Ore. (AP) — Organic farmers fear this year’s spring breezes will be carrying pollen from genetically altered sugar beets, which they say could render their crops worthless, and they hope to persuade a federal judge this week to halt the plantings nationwide.

Experts and industry groups say such an injunction could jeopardize U.S. sugar supplies, about half of which comes from the biotech beets planted on more than 1 million acres in 10 states stretching from Michigan to Oregon.

”It will be a big problem,” if the injunction is granted, said Carol Mallory-Smith, professor of weed science at Oregon State University. ”The industry really had converted to this.”

The beets, engineered to be resistant to Monsanto’s popular herbicide Roundup, comprise 95 percent of the crop after two seasons of planting. All the seed comes from Oregon’s Willamette Valley.

Organic farmers, food safety advocates and conservation groups already have won a lawsuit forcing federal authorities to reconsider their 2005 approval of the Roundup Ready beets for unrestricted use, saying the government failed to take a hard look at cross-pollination risks.

If granted at a hearing scheduled for Friday in San Francisco, a requested injunction would halt planting of the altered beets until the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service does an environmental impact statement — a process that could take two or three years.

The farmers also want to bar the sale of any sugar made from generally engineered beets.

”The sugar beets were unlawfully deregulated,” said Paul Achitoff, an attorney for Earthjustice, the environmental public interest law firm representing plaintiffs. ”The court has already found that. Legally, they shouldn’t be on the market.