A&P's Plus food stores, rated the supermarket chain with the lowest prices in a recent survey by an area consumer group, plans to close its doors next month, food industry sources said yesterday.

The Great Atlantic & Pacific Tea Co. operates about 30 of the low-cost, no-frills discount food stores, seven in the Washington area.

Although officials at Plus headquarters in Florence, N.J., confirmed plans to close the stores, A&P executives refused to return phone calls about the move.

A&P reportedly has already notified suppliers that it plans to phase out the stores and has asked them to stop shipments of merchandise.

Employes at the stores have also been notified in the past few days of the impending store closings.

Modeled on the Plus stores operated in West Germany by Tengelmann Group, which owns A&P, the stores carry a limited assortment of items in large sizes at low prices, offer little meat or produce and require customers to bag their own purchases.

A survey done in June and released recently by Washington Consumer Checkbook, a local non-profit consumer publication, found that a market basket of products purchased at Plus had an indexed cost of $85, compared with a cost of $100 at a standard A&P or Giant food store. The only lower prices were found at a food-salvage warehouse store in the District.

Despite their competitive prices, the Plus stores never captured a significant share of the Washington grocery market, which is dominated by the Safeway and Giant chains.

The Plus stores accounted for only about 0.7 percent of total local grocery store sales, according to the Consumer Checkbook survey. In addition to the Plus store sales, the conventional A&P stores have about 3.3 percent of the market, down from 10.5 percent four years ago.

Closing of the Plus stores apparently will not affect the other A&P stores, and is not expected to have a major impact on the $3 billion supermarket business in the Washington area.

A recent study by Food World, a Columbia-based trade publication, showed that Giant dominates the market with about 41 percent of total sales and Safeway is second with about 32 percent.

Grand Union is No. 3 in the market, with 9.25 percent of sales, according to Food World, and the combined sales of A&P and Plus ranked that company fourth in the market.

A&P has been cutting back its roster of regular A&P supermarkets, and has closed 13 stores in the Washington area and nine more in Baltimore and the Eastern Shore areas early last year.

A&P began opening Plus stores four years ago, and at one time had about 70 Plus stores nationwide. But the stores have not been as successful in recouping A&P's slipping market share as the company had hoped. The company began closing Plus stores a couple of years after they were opened.