After PGDBM, you probably wont be able to move as faculty in Institutes, as a PhD is neccessary. If you ought move as a Faculty in School, you may require a B.Ed, as made compulsory by Most Regulatory Boards for recruitment of Teaching Positions. Nowadays, however you easily can pursue a B.Ed in Distance Education Mode from Reputed Universities like IGNOU, AMITY or Sikkim Manipal.

As far as PhD in Management is concerned, you may require a CSIR NET Scorecard besides a Valid CAT/GMAT Score, for JRF, FPM and PhD positions, depending on requirements of various Management Institutes and Universities.