The visitors started the brighter of the two and Jay Spearing nearly put them in front when his shot was deflected off Richard Stearman after just 30 seconds, but the ball bounced the wrong side of the post with Carl Ikeme stranded.
Wolves captain Danny Batth, who netted in midweek against Charlton Athletic, nearly had his second goal of the week, but his effort was well saved by Andy Lonergan on 18 minutes.
Lee Evans had a chance three minutes later, but his strike was too high moments after Craig Davies tried his luck for Bolton.
As the first half drew to a close, Dicko made the most of some indecision in the Bolton defence to nod home his third of the campaign.
Jermaine Beckford earned his side a penalty when he was brought down by Batth after the restart, but Owen Garvan wasted the chance to level the score by missing the spot kick.
Liam Feeney had a chance to equalise with six minutes remaining, but his effort was too close to Ikeme.