September 22, 1990

LEAD: Citing a ''serious crisis in executive power,'' President Mikhail S. Gorbachev urged the national Parliament today to grant him sweeping powers to halt the country's slide toward social and economic collapse.

LEAD: Vowing to continue his campaign for governor of New York but to turn it into a populist struggle, the Republican candidate, Pierre A. Rinfret, yesterday turned on the party leaders who had nominated him and accused them of being interested only in their own political fortunes.

LEAD: As Congressional and Administration budget negotiators wrestled with an impasse over cutting the capital gains tax rate, President Bush pointedly avoided criticizing a suggestion by the Senate Republican leader, Bob Dole of Kansas, that the tax cut be severed from the budget package.

LEAD: In a telling new sign of the problems afflicting the nation's banks, the Chase Manhattan Corporation said yesterday that it would take a $1 billion charge against earnings and reduce its work force by 5,000 employees. The nation's second-largest bank also took the unusual and humbling step of cutting its stock dividend by more than 50 percent as part of a drive to rebuild its financial strength.

LEAD: Prospects for an end to violence in black townships grew today when Nelson Mandela, the African National Congress leader, made a surprisingly warm overture to Chief Mangosuthu Gatsha Buthelezi, the leader of the Zulu-based organization vying with the congress for influence.