Virginia yesterday became the first Washington-area jurisdiction to impose restrictions on California produce, ordering that all fresh fruits and vegetables from that state be certified free of Mediterranean fruit flies before being placed on supermarket shelves.

Officials said they fear the flies could infest Virginia's valuable apple orchards.

Under the order, to take effect Wednesday, the state's 17 agricultural inspectors are directed to spot-check produce arriving at the state's major food distribution centers and seize any produce showing signs of Medfly infestation.

Food industry officials predicted the action will not adversely affect consumers in the Washington area.

Despite federal precautions already in place, Virginia officials said yesterday they believe the state's apple crop needs additional protection and said their inspectors will be authorized to quarantine any suspected produce for 90 days.

Evidence of Medflies could result in some food shipments being turned back, fumigated or destroyed, officials said.

While 35 of Virginia's largest fruit and vegetable wholesalers receive a majority of their foods from California, state agriculture authorities said they have seen no signs of the insect in produce from there.

The quarantine process announced yesterday requires that wholesalers show proof of origin for any produce to be sold in the state.

"We do not plan to set up any roadblocks," said Bill Southall, director of product regulation in Virginia's agriculture department. "But there's a possibility in any program that something might inadvertently come through."

Spokesmen for the Washington area's two largest supermarket chains, Safeway and Giant, also said yesterday they have not received any produce from California's infested areas and that the Medfly problem there has had no effect on Washington food prices.

"All the fruit that we have here is certified that it does not come from contaminated areas," said Giant press aide Susan Portney. Nearly all the produce now on Giant's shelves in the Washington area is California-grown.

Giant already requires that they be certified as coming from Medfly-free areas before shipping them to supermarket shelves, she said.

Under a quarantine placed on several California counties, 43 fruits and vegetables regarded as potential Medly hosts must be treated for the pest before they can leave the state.

In imposing its quarantine, Virginia joins a half dozen states that have acted to restrict sales of California produce as a result of the Medfly infestation. Southall said the 90-day period is expected to be sufficient to allow Virginia's apple growers to harvest their crops.

Medflies that arrive after that, agriculture authorities said, probably could not survive the state's winter.

Virginia authorities said they have received permission to visit warehouses in Landover, which supply Northern Virginia supermarkets.