BUENOS AIRES, Aug 6 (Reuters) - Argentine stocks rebounded sharply on Wednesday after four straight sessions of losses, as investors snatched up shares in companies that reported strong second-quarter earnings.
The MerVal benchmark index .MERV jumped 3.45 percent to end at 1871.66 points, after sinking 7.2 percent over the prior four trading days.
"The MerVal's strong rebound was due to an improved climate after Siderar and Petrobras Participaciones announced good quarterly earnings," said Mariano Tavelli, trader at Tavelli y Compania brokerage.
Petrobras Energia Participaciones PCH.BA, the local unit of Brazilian state-run oil company Petrobras (PETR4.SA) APBR.BA, surged 7.3 percent to 3.37 pesos a share after reporting its second-quarter net profit nearly quadrupled from a year ago.
Steelmaker Siderar SID.BA gained 2.6 percent to close at 27.2 pesos per share, a day after reporting a 167 percent jump in second-quarter net profit from the same period of 2007.
Trade volume on the overall market was a brisk $42.6 million. Of active shares, 77 rose, 17 fell and 13 were unchanged.
Meanwhile, Argentine sovereign debt fell 1 percent on average in over-the-counter trade, with the dollar-denominated 2033 Discount bond falling 1.4 percent and the 2038 Par dollar paper slumping 1.3 percent.
Traders said Argentine bonds continue to fall as institutional investors opt for less risky assets.
The peso currency weakened slightly against the dollar in a quiet session in which the central bank acted to stabilize expectations, traders said.
In formal interbank trade, where the central bank regularly intervenes, the peso slipped 0.08 percent to 3.0425/3.0450 per dollar ARS=RASL. In informal trade between foreign exchange houses, as measured by Reuters, the peso weakened by the same percentage to end at 3.0600/3.0625 per dollar ARSB=. (Reporting by Walter Bianchi; Writing by Hilary Burke; Editing by Leslie Adler)