P.M. BRIEFING : Prudential-Bache Loss Expected

Prudential-Bache Securities Inc. is expected to report a larger-than-expected $250-million loss for 1990, the parent of the Wall Street firm said today.

Prudential Insurance Co. of America also said it had added $200 million in additional equity capital to the struggling investment firm, which in recent months has abandoned or cut back several key businesses.

The announcement is the latest evidence of the growing recession at securities firms, which have laid off thousands of employees in recent months and scaled back once-lucrative areas such as investment banking.

The anticipated $250-million loss at Prudential-Bache exceeds earlier estimates by analysts of losses up to $100 million. Including 1990, Prudential-Bache has been unprofitable in three of the last four years. The firm lost $51 million in 1989.