A European Parliament member has become the latest public figure in Germany to be stripped of her doctorate for plagiarism after the defence minister was forced to quit earlier this year.

Heidelberg University in western Germany said it had withdrawn Silvana Koch-Mehrin's academic title after an enquiry found that "substantial parts" of her 2000 doctoral thesis were copied from others.

Koch-Mehrin, 40, was once seen as a rising star of the pro-business Free Democrats (FDP), Chancellor Angela Merkel's junior coalition partners, but her popularity had already waned before plagiarism allegations surfaced in May.

On May 11 she quit as head of the party in the European Parliament, as deputy speaker of the parliament and as a member of the FDP board, but remained an MEP.

Karl-Theodor zu Guttenberg, the most popular figure in Merkel's cabinet, resigned as defence minister on March 1 after his doctorate was rescinded for plagiarism in his 2006 thesis.

His alma mater, Bayreuth University, found that "the standards of good scientific practice were obviously grossly abused and it was obvious that plagiarism was involved."

The episode earned the aristocratic minister the nickname "Baron Cut-and-Paste" and prompted the academic works of other figures to be scrutinised, including through collaborate websites known as "wikis".

Another casualty was Veronica Sass, the daughter of Edmund Stoiber, the long-serving former state premier of Bavaria who unsuccessfully ran for chancellor in 2002.