EVANSVILLE, Ind., Nov. 20 (UPI) -- More than a month after Florida agricultural inspectors found a highly virulent virus in imported tomatoes from Mexico, the U.S. Department of Agriculture said it will enact strict import restrictions on tomatoes and peppers.
Beginning Friday, all tomato and pepper seeds, plants or fruits from countries known to have tomato brown rugose fruit virus must be "officially tested and certified free of the disease" before they may enter the United States, the agency said.
The USDA "is taking immediate action to ... protect U.S. tomato and pepper production worth more than $2.3 billion annually," the agency said in a statement. The "virus can cause severe fruit loss in tomatoes and peppers. It is easily spread through the use of contaminated tools, hands and plant-to-plant contact."
The virus is not dangerous to humans.
The Florida Department of Agriculture announced it had discovered infected tomatoes Oct. 9 in Naples and Gainesville. The tomatoes were destroyed, the agency said. But it warned that more could arrive in any state in the country.
Since it was first discovered in Israel in 2014, the virus has spread to China, Mexico, Germany, Italy, Greece, the United Kingdom, Jordan, Turkey and the Netherlands. It also appeared once in a California greenhouse, but was eradicated there in 2018.
The virus causes yellowing of leaf veins in infected plants. The fruit also shows yellowed, wrinkled or necrotic patches.
There is no treatment for the disease. An infected field could lose 30 to 70 percent of its tomatoes or peppers, according to the Florida agriculture department.
"Mexican-grown tomatoes carrying the ToBRFV virus are a serious threat to Florida," Nikki Fried, the state's agriculture commissioner, said in October. "For the past six months, our inspectors have been watching vigilantly for the ToBRFV virus, and are moving swiftly to prevent its introduction in our state."
The restrictions are a relief to the American tomato and pepper industries -- but it could make it more difficult to get seeds into the country, said Ric Dunkle, the senior director for seed health and trade at the American Seed Trade Association.
The USDA already has strict import restrictions on tomato and pepper seeds. Those restrictions are meant to guard against pospiviroid, another plant pest, and they have slowed seed imports nearly to a stop, Dunkle said.
The tomato brown rugose fruit virus restrictions are a necessary hurdle, he said, adding, "It's a nasty virus. Everybody is worried about it."
Pospiviroidae, on the other hand, might be less of a threat, Dunkle said.
They are known to infect tuber plants, like potatoes, and often are carried silently on tomato and pepper seeds, the USDA has said. But industry groups say that positive tests rarely translate into infected plants. What's more, it might be possible to sterilize infected seeds.
But under the current restrictions, all seeds must be tested and verified disease free in their country of origin -- something most origin countries do not have the means or ability to do.
With the restrictions slowing the volume of tomato and pepper seeds entering the United States, tomato growers are concerned they will not have enough seeds to last the upcoming season, Dunkle said.
The majority of America's seeds are produced in China, Mexico and other countries in South America.
"It's not a good picture now," Dunkle said. "I'm not going to mince words. We're hoping to get some sort of stability by 2020."