A federal judge issued a ban Friday on any future planting of genetically modified sugar beets, potentially imperiling nearly all of the United States crop.
Judge Jeffrey S. White of United States District Court in San Francisco ruled that the Department of Agriculture had failed to conduct a required environmental impact statement before approving the genetically modified beets. Such beets now account for about 95 percent of the nation’s sugar beet production and nearly half of the sugar produced.
It is unclear how quickly the Department of Agriculture could complete the environmental study and reconsider approval of the genetically engineered beets. The environmental groups that brought the lawsuit argued that genetically modified beets would contaminate unmodified crops grown nearby by organic farmers and others who chose to plant conventional seeds.
Sugar beet growers sold the 2007-8 crop for about $1.335 billion, according to U.S.D.A. data.