WASHINGTON — Banker Elizabeth Duke was sworn in as a member of the Federal Reserve, which has been battling housing, credit and financial crises with a short staff.

Duke also will take part in Tuesday's Fed meeting, where it was widely expected that a key interest rate will be held steady. Fed Chairman Ben Bernanke administered the oath of office before the Fed gathered to assess the economy, which has been struggling with weak growth and high energy and food prices that threaten to spark inflation.

President Bush tapped Duke and another banker, Larry Klane, to vacant seats on the seven-member Fed board more than a year ago. Although Duke was confirmed, the Senate has not moved ahead on Klane's nomination. The openings have left the Fed spread thin at a time of much turbulence in the economy.

Meanwhile, Fed Governor Frederic Mishkin will leave at the end of August and return to teaching at Columbia University, creating a second opening at the central bank if Klane's nomination stays stalled. Tuesday's meeting will be the last for Mishkin.

Bush also has appointed Fed Governor Randall Kroszner to a new term, which also requires Senate approval. Kroszner's term has expired, although he is allowed to continue serving until a replacement is sworn in. Democrats haven't shown any inclination to grant Kroszner a new term.

President Bush chose Ben Bernanke to be the Fed's chairman and appointed all the current members on the Fed's board. That has allowed Bush to put his imprint on the institution. The Fed sets interest rate policy and is responsible for the safety and soundness of the nation's financial system.

Before joining the Fed, Duke, 56, was senior executive vice president and chief operating officer of TowneBank, a Virginia-based bank. Prior to that she was an executive at other banks, including Wachovia, SouthTrust Bank and Bank of Tidewater in Virginia Beach, Va.

Duke received her bachelor's degree from the University of North Carolina at Chapel Hill and her M.B.A. from Old Dominion University.