Five southern states have decided to quarantine all California fruits and vegetables because of a Mediterranean fruit fly infestation. The action is expected to raise the cost of the California Medfly campaign to at least $500 million.

Gordon Snow, a spokesman for the California Department of Food and Agriculture, said Alabama, Florida, Mississippi, South Carolina and Texas had announced that California produce would not be accepted without expensive fumigation or Medfly trapping throughout the state.

The decision is expected to raise supermarket prices in the five states, and in any other states that decide to follow suit.

"We have quarantined the state of California," said Bob Champion, Texas' deputy agriculture commissioner.

He said Texas and the other four states, members of the Southern States Plant Board, would require California to fumigate its outgoing produce or set up five Medlfy traps every square mile in growing areas and certify no Medflies were found in 30 days.

Snow placed the cost of lowered sales, fumigation, new traps and the continued fight against the San Francisco Bay area infestation at $500 million this year.

He said some farmers in California's Sacramento and San Joaquin valleys, centers of a farming industry that provides half the nation's fruits and vegetables, were trying to set up fumigation chambers, but the costs and technical problems were great. California law, he said, requires that all fumigation gases be recovered, so the chambers must be airtight.

Referring to the five states which have slapped their quarantine on California, Snow said, "they are the heavies."

U.S. Agriculture Secretary John R. Block had threatened quarantine on all shipments from California last week, but dropped the demand when California Gov. Edmund G. (Jerry) Brown Jr. reluctantly agreed to begin aerial spraying in the infested San Francisco Bay area.

Aerial spraying program, now in its fourth day, has been plagued by mechanical troubles and a shortgage of helicopters, and covered only 58 of the 160 square miles where Medfly larvae have been found.

State officials managed, however, to get five spraying helicopters into the air for the first time during this morning's spraying run and say they will have the first sweep of the area completed by Sunday.

Snow said six other members of the Southern States Plant Board -- Georgia, Kentucky, Louisiana, North Carolina, Oklahoma and Tennessee -- have announced new but less stringent requirements for importation of California fruits and vegetables.

He said the six states have asked that California set up 10 traps per square mile for all growing areas within 100 miles of the currently infested area, which includes most of the three counties.

Snow said California officials are moving to install that trapping system. The six states will accept fruits and vegetables from those areas with a certification that no Medflies have been found.

Southern states have been particularly concerned about California's Medfly problem ever since the first larvae, apparently brought in accidentally from Hawaii, appeared on the San Francisco peninsula last summer.

Several of the southern states earn substantial income from the sale of peaches and pears, which are a favorite target of the tiny Mefly. The insect lays eggs inside 200 varieties of fruits and vegetables. The larvae feed on the fruit, making it soft and unmarketable.

The agriculture commissioner for San Joaquin County, Erwin Eby, said his staff was trying to set up the required number of traps but that the 30-day delay would be a problem.

He said he thought the trapping he was already doing in his county was sufficient, "but for some reasons I don't understand those states now want more."