Second-half strikes from Daniel Powell and Ibehre handed Karl Robinson's men their third straight home win and ended struggling Rovers' mini-revival.
The Dons dominated from the start and Ibehre's overhead kick dropped narrowly over the crossbar before Lewis Guy fizzed a cross-shot just past the post after a neat one-two with Luke Chadwick.
Powell then had two shots cleared off the goal-line, the first by Mark McChrystal after rounding Rovers keeper Tony Warner and the second by Aaron Cresswell on the stroke of half-time.
But it was third time lucky for Powell as he fired the Dons ahead just 14 seconds after the restart, slamming home Ibehre's cut-back from the byline following Michael Kay's miscue.
Cresswell and John Welsh both forced Dons keeper David Martin into low saves with shots from distance as Tranmere battled back. But Dons forward Guy had a goal ruled out for offside before Ibehre sealed the win in the 70th minute, wriggling free of Ash Taylor in the box to drill a low shot past Warner.