Durrell Berry found Blissett with a neat cross to put the visitors ahead.
Gulls goalkeeper Dan Lavercombe denied Jamie Lucas an equaliser and Delano Sam-Yorke saw an injury-time header come off the crossbar for the hosts.
Despite the victory, Torquay are still 10 points from safety, while Wood join them in the relegation places.
Nathan Blissett scored the only goal of the game at Boreham Wood as bottom side Torquay United won in the league for the first time since Boxing Day.