At 36 years old Bucchi, formerly coach with the club's youth side, becomes the youngest coach in Serie A ahead of 37-year-old Andrea Stramaccioni of Inter Milan. He is also Pescara's third coach of the season.
Bergodi was sacked after a 1-0 defeat to Udinese sent the league new boys to the foot of the table. He had taken over at the helm when Giovanni Stroppa resigned in late November following a poor start, but failed to stop the rot.
Pescara have lost 18 times in 27 games so far in a campaign which has left them bottom on 21 points, the same number as fellow strugglers Palermo and Siena.
Bucchi's appointment is the 12th to be made in Serie A since the campaign began in late August.
Fellow strugglers Palermo have already seen three changes, beginning the season with Giuseppe Sannino, who was replaced by Gian Piero Gasperini after only a few games.
Gasperini was then replaced by Alberto Malesani, only to be recently reappointed by Palermo's trigger-happy president Maurizio Zamparini.
A record 19 coaches were sacked in Serie A last season.
Champions Juventus sit top of the league with a six-point lead on Napoli.
