Florida's tomato industry is in "complete collapse" and growers in California and Mexico are having trouble selling their crops as US regulators hunt the source of a salmonella outbreak linked to certain tomato varieties, growers said on Tuesday.

In Florida, the No.1 US tomato producer, $40 million worth of tomatoes will rot unless the US Food and Drug Administration quickly traces the source of the outbreak and clears the state's produce, an industry official said.

"We've had to stop packing, stop picking," said Reggie Brown, executive vice president of the Florida Tomato Growers Exchange.

"The stuff that should have been harvested over the weekend won't survive more than another day or so. The stuff we have in storage is getting riper every minute and at some point it will have to be disposed of," Brown said.

The FDA warned US consumers on Saturday that the outbreak was linked to eating certain raw red plum, red Roma, and red round tomatoes, and products containing those tomatoes.

Major restaurant and grocery chains stopped selling those varieties, and some stopped selling all raw tomatoes entirely.

US growers produced $1.28 billion worth of tomatoes last year, according to the US Department of Agriculture.

Florida produces an annual crop valued at $500 million to $700 million, and supplies more than 90 percent of the nation's tomatoes this time of year, Brown said.-Reuters