Stocks in America fell for a second day as a slump in commodity producers overshadowed gains in airlines and consumer companies after oil slid to a five-month low.

Alcoa Inc., Exxon Mobil Corp., and Chevron Corp. tumbled more than 3% each, causing the Dow Jones Industrial Average to erase a morning rally of almost 247 points. EBay Inc. tumbled 3.5% as Stifel Nicolaus & Co. reduced its price estimate for the largest auction site, while Apple Inc. slid 2% after Thomas Weisel Partners cut profit estimates. Delta Air Lines Inc. climbed 13% as crude, the airline industry’s biggest expense after it is refined into jet fuel, slid more than $5 a barrel.

The retreat in commodity producers and technology companies led the S&P 500 to erase a morning rally of as much as 1.6%. Energy shares in the S&P 500 dropped 4.6%, the most in a month, and extended their decline from a May record to 21%. Producers of raw-materials retreated 2.5% after gold, silver, and copper also declined.

Alcoa, the world’s third-largest aluminum producer, lost 5.2% to $30.46 for the biggest decline in the Dow average. Exxon, the largest oil company, slipped 3.4% to $77.32. Chevron slipped 3.5% to $83.29. Peabody Energy, the biggest American coal producer, fell $7.53 to $55.42. Massey Energy, the second-best performer in the S&P 500 this year, dropped $6.61 to $59.35. Crude for October delivery declined $5.75, or 5%, to $109.71 a barrel in New York, the lowest close since April. Oil will likely drop further in the next three to six months, investor Marc Faber said in a Bloomberg Television interview yesterday.

“Energy stocks are in a correction and they’ve got a bit further to go,” a chief investment officer of 1st Source Corp. Investment Advisors, which manages $3 billion, Ralph Shive, said. “People were speculating, ‘What if we have a replay of Katrina? What if this one is a real whopper and energy prices spike up?’ After that didn’t happen, they had to unwind those positions.”

The dollar rose to the highest level against the euro in almost seven months as crude oil fell and traders speculated that the Federal Reserve’s monetary policy will help the American economy outperform Europe and Asia.

Technology stocks, the second-biggest contributors to the S&P 500’s decline, fell 1.4%.

Benchmark indexes rallied in the morning even after the Institute for Supply Management’s factory index fell to 49.9 last month from 50.0 the prior month as companies pared investments and production in the face of weakening consumer spending and high commodity costs. A report from the Commerce Department showed construction spending in America fell more than economists forecast in July as work slowed on homes, power plants, and factories.