By Guillermo Parra-Bernal

SAO PAULO, July 7 (Reuters) - Brazil stocks fell and the real gained on Tuesday as talk of a need for a second government stimulus package in the United States ignited concern over the state of the global economic recovery and the dollar.

The United States should be planning for a possible second round of fiscal stimulus to further prop up the economy after a rescue package launched in February, an adviser to President Barack Obama said on Tuesday. In addition, investors are moving cautiously ahead of the start of the U.S. earnings season.

"People are taking advantage of the volatility and the deterioration of investor sentiment to book some profits," said Helena Biasotto, who helps manage about 5 billion reais ($2.6 billion) in assets for Banrisul in Porto Alegre, Brazil.

The Bovespa stock index .BVSP pointed to a fourth day of losses and slid 1.5 percent to 49,878.96 points. Preferred shares of Vale (VALE5.SA: Quote, Profile, Research) led declines on concern a plan to sell convertible notes may dilute the value of shareholding.

The index fell to its lowest level since June 24, "opening room for some good stock-picking opportunities," Biasotto said.

Yet, the Bovespa futures contract due in August INDQ9 fell 1.5 percent in early trading. The contract due in October 2010 was unchanged at 57,300 points.

The real (BRBY: Quote, Profile, Research), Brazil's currency, strengthened for the first day in four and gained 0.4 percent to 1.954 reais to the dollar.

Moody's Investors Service said on Monday it might give Brazil an investment-grade rating, citing the economy's resilience during the credit crisis.