Wheat prices rose again Thursday on concerns about poor weather conditions, while gold and silver shot higher as traders sought refuge from a steep decline in the stock market.

Wheat rose 3 percent, or 19 cents, to $6.5775 per bushel on Thursday. Prices have been climbing for most of the week as traders worry that dry weather in the U.S. and Russia will crimp supply.

Corn and soybeans also rose, but not as much. Corn climbed 5 cents to $6.25 per bushel. Soybeans climbed 16 cents to $14.38 per bushel.

Most metals rose as traders sought safety from the plunging stock market. The Dow Jones industrial average lost 156 points to close at 12,442, and is now down 5.8 percent since the end of April.

Gold for June delivery rose 2.5 percent, or $38.30, to $1,574.90 per ounce. May silver rose 3 percent, or 82.6 cents, to $27.996 per ounce. July platinum rose 1.5 percent, or $21.20, to $1,453.40 per ounce. June palladium rose 2 percent, or $11.75, to $605.85.

Copper was the outlier. The May contract for the industrial metal fell a tiny fraction _ about 0.2 percent, or about half a cent _ to $3.4795 per pound.

Oil prices followed copper lower. Investors have been unnerved because of a possible slowdown in China, where manufacturing fuels oil demand, and political stalemate in Greece, which could drag Europe into even more uncertainty.

A stronger dollar also tends to send down the price for oil and other commodities that are traded in dollars, because the commodity becomes more expensive for traders who use other currencies.

Benchmark oil fell 25 cents to finish at $92.56 per barrel in New York. Brent crude, which is used to price many international oil products, fell $2.26 to $107.49 per barrel in London.

Heating oil dropped 4.86 cents to end at $2.849 per gallon and gasoline futures declined 4.27 cents to $2.8782 per gallon.

Natural gas fell 2.4 cents to end at $2.594 per 1,000 cubic feet.