FUTURES MARKETS;Corn Prices Jump on Report That Demand Has Not Slacked

Corn prices jumped on the Chicago Board of Trade yesterday after an Agriculture Department report showed that high prices had not deterred demand.

On other markets, natural gas surged for a second day, while copper continued a recovery.

Corn prices rallied after the Agriculture Department estimated that American bins contained just 1.7 billion bushels of corn as of June 1. That figure is half last year's level and stunned grain traders, who guessed it would be about 10 percent higher.

If consumption is not curbed, analysts estimate the country would have 2 to 12 days of reserves when newly harvested corn begins arriving at elevators in September. Standard reserves are about 90 days.

Traders had thought demand had slowed in recent weeks as foreign buyers were priced out of the market. But the data yesterday showed that customers were not cutting back their corn purchases.

Prices were also bolstered by forecasts that called for dry, 100-degree weather in the Midwest over the next few days, said William Biedermann, an analyst with Allendale Inc. in Crystal Lake, Ill.

Corn for July delivery rose 34.75 cents, to a contract high of $5.1625 a bushel. Because the contract was entering the period in which buyers could take delivery of corn, it traded without the normal 12-cent limit. Yesterday's move was the largest jump since July 20, 1973, according to the Chicago Board of Trade.

Natural gas climbed after a leak in the Blue Water Gathering System curbed supplies from the Gulf of Mexico. The leak, following news of a leak on Thursday that closed two natural gas platforms off Louisiana, intensified concerns about supply at a time when hot weather drives up demand for electricity to run air- conditioners.

August natural gas rose 12.4 cents, to $2.91 for 1,000 cubic feet on the New York Mercantile Exchange.

Copper for July delivery edged 1.05 cents higher, to 91.85 cents a pound -- slightly off its high of 93.85 cents a pound at the Comex division of the New York Mercantile Exchange. September copper gained 0.9 cent, to 90.40 cents a pound -- off its high of 92.40 cents a pound.