The coldest temperatures in four years left icicles in the citrus groves of central Florida yesterday and destroyed an estimated one fifth of the state's orange crop.

As a second night of frigid tempertures approached, officials in the Sunshine State feared further destruction of citrus fruit and vegetables. Already, widespread damage to corn, pepper, tomato, pea, cabbage and cucumber crops had been reported as far south as Miami.

In plant City, the "Winter Strawberry Capital of the World," fields resembled outdoor skating rinks -- the result of ice formed when sprinklers were left on all night in an attempt to save the crop. James Clarke, who oversees 3,000 acres of citrus trees in three central Florida counties, said, "Just about all the fruit on the trees had ice on it."

Farmers estimated losses in the millions and predicted slightly higher prices at the grocery store for winter vegetables and orange juice. Florida Citrus Mutual, a cooperative representing 15,000 growers, estimated about 36 million boxes of oranges had been destroyed. This is the equivalent of 49 million gallons of orange juice -- or from 17 to 20 percent of the Florida orange crop.

Bobby F. McKown, the cooperative's executive vice president, said most growers expect damage to be on a par with a January 1977 freeze that almost doubled the wholesale price of oranges, increasing prices from $1.87 to $3.55 a dozen. That freeze, however, hit the entire state while the current one excluded some parts of the eastern coast of Florida, he said.

Temperatures in the teens and low 20s were reported throughout the interior and west coastal areas of Florida Monday night, and were expected to continue last night, part of a cold wave gripping most of the East Coast of the nation.

In Massachusetts, Gov. Edward J. King declared a statewide enery crisis saying the same cold snap had caused a shortage of natural gas, spreading from Lowell and Cape Cod toward Boston. "We are entering a very critical period where natural gas consumption must be reduced," King said.

In Miami, National Weather Service spokesman Alvin Samet said yesterday capped a five-day period among the "top 10 coldest" since 1911. Jacksonville recorded a morning low of 13, two degrees below the previous January record set 95 years ago. Tourists at Miami Beach, seeking a respite from the northern cold, were greeted with a record morning low of 36 degrees.

In St. Petersburg, one man died when the charcoal grill he was using to heat his apartment fell over, starting a fire. A Jacksonville man fell asleep outdoors and died of overexposure.

The most recent similar cold wave hit Florida in 1977. Ironically, like this one, it occurred in the days immediately before the presidential inauguration. About 50 million boxes of oranges were lost at that time, sending orange juice prices skyrocketing.

Unless the damage spreads dramatically, experts expect a much smaller price increase this year -- perhaps no more than 20 percent. Orange juice prices have been lower this year than in the past two, and a bumper crop of Brazilian oranges has flooded the market.

Oranges damaged by freezing can still be used for juice, if they can be picked fast enough. But officials at the Florida Citrus Commission, a state agency, said they will consider putting an embargo on the shipment of oranges leaving the state on Friday, a move designed to protect consumers from purchasing damaged fruit.

Citrus growers complained they were unable to protect their groves with smudge fires, the traditional method, because of government regulations prohibiting all but cleanburning fuel oil heaters. "With the cost of fuel and labor what it is, less than 10 percent of the groves now have any protection," said Florida Citrus Mutual spokesman Earl Wells. "The other 90 percent just keep in touch with each other and pray."

In Plymouth, Fla., a spokesman for Fred M. Dunn Citrus Nurseries said 30,000 of their 200,000 orange trees had been lost. Grapefruit trees across the state were less severely hit.

Vegetable growers were also frozen out overnight.

Fruit is damaged when exposed to temperatures of 26 degrees for four hours or longer. About 90 percent of Florida's orange crop is made into orange juice, and the state produces about 95 percent of the nation's orange juice.