With half of California’s navel orange crop destroyed by a cold snap, the wholesale price of the fruit soared Tuesday as agriculture officials warned that consumers soon would be paying more for other produce, such as avocados, carrots and lettuce.

California Gov. Arnold Schwarzenegger declared a state of emergency Tuesday in 10 counties hardest hit – even as state officials predicted that the frigid temperatures would continue in many agriculture zones through the weekend. Forecasters were predicting lows 7 to 10 degrees below normal this week, raising the specter of more crop damage.

In the strongest sign that the freeze will hit consumers, navel orange prices doubled at the wholesale level, with the highest-grade, large-sized navels increasing from about $17 per bushel last week to about $35 Tuesday.

California is the nation’s main source of navels, and, unlike other crops, there is little foreign supply.

“Expect retail prices to triple,” said Todd Steele, owner of Royal Vista Marketing, a citrus brokerage in Visalia, Calif. The price spike is expected to hit supermarkets in the next two weeks, when the current inventory dwindles.

In the hard-hit San Joaquin Valley, agricultural officials said they feared the damage would go beyond oranges to the broccoli, beet, carrot and lettuce crops that just began to grow for winter harvest.

To meet the national need for fresh winter fruit and vegetables, distributors say they already have begun negotiations with growers in Chile and other food-exporting countries.