Key Reformer Quits East German Communist Party : East Europe: The Dresden mayor’s resignation deals the struggling organization another blow.

The reeling East German Communist Party received another sharp blow late Sunday with the resignation of one of its brightest reformist stars.

The 46-year-old mayor of Dresden, Wolfgang Berghofer, announced he is leaving the party along with 39 other senior party members from the southern part of the country. The group demanded that the party disband.

Berghofer’s resignation had been rumored ahead of time, but it still came as a severe setback to the Communists, who are struggling to regain credibility with East German voters in preparation for the country’s first free elections, scheduled for May 6.

Some analysts predicted that Berghofer’s defection will result in the collapse and dissolution of the party before the election takes place. The Dresden mayor was generally considered the party’s No. 3 in terms of popularity.

Berghofer’s announcement came Sunday evening, on the heels of an earlier action at an emergency party congress, expelling former leader Egon Krenz from membership. Krenz, the man who opened the Berlin Wall in early November, had taken over as head of East Germany’s government in October, replacing the toppled Erich Honecker. Honecker was expelled from the party in December, the same month that Krenz quit as party chairman.

The emergency congress also threw out of the party 13 other members of the old ruling Politburo, including Guenter Schabowski, a reputed reformer, and former Defense Minister Heinz Kessler.

But at the end of a long weekend meeting, the congress continued to resist pressure that the party disband.

Krenz appealed his expulsion, arguing that he had saved the party from disintegration by opening the Berlin Wall and undertaking other liberalizing reforms. His appeal made him the first former top leader to fight back publicly. A number of other former top party people were expelled last month, and nine are in prison on charges of corruption.

Senior party members who joined Berghofer in quitting issued a sharply critical statement Sunday, declaring that the Communist Party had “ruined the country and should be dissolved.” They also called for reunification with West Germany, a market economy, and the cleanup of a heavily polluted environment.

As the emergency meeting got under way here Saturday, a motion by some members to disband the party was overruled by a secret vote with the support of new party leader Gregor Gysi, who himself was catapulted into the top position as a reformist-minded dissident lawyer.

Among the defectors who joined Berghofer in leaving the discredited party Sunday was Friedrich Wokurka, who heads the state-owned Robotron company, East Germany’s largest electronics firm.

Most political observers believe that Berghofer will join the newly created Social Democratic Party, a sister to the West German party of the same name. The West German Social Democrats form the main opposition to the ruling coalition, headed by Chancellor Helmut Kohl’s Christian Democratic Union.

Berghofer did not announce his future plans Sunday, but if he should move over to the Social Democrats as expected, it could give the new party a significant edge in the coming election, according to political specialists.