The utility back will make his bow in Blue having returned from international duty with Los Pumas fresh from their historic triumph over France.
Tuculet takes over from Gareth Anscombe at the back as the Wales qualified Kiwi makes his first start at outside-half.
Geraint Walsh comes in on the wing for Dan Fish and another new signing, Tom Isaacs, could also make his first appearance for the region from the bench.
Filo Paulo is back in the second row after international duty with Samoa where he partners Josh Turnbull who moves from the back row.
Josh Navidi is the final change to the side as he takes the Number Eight jersey for the home fixture. Ellis Jenkins and Macauley Cook are named flankers.
For Treviso, Meyer Swanepoel will replace Mat Luamanu, who was injured in the game against Leinster, with Dean Budd moving to number 8. Angelo Esposito is on the wing in place of Andrea Pratichetti who moves to the bench.
Director of Rugby Mark Hammett said: “It’s important we produce the right response to defeat in Edinburgh as we look to secure our first win of the Guinness PRO12 season at BT Sport Cardiff Arms Park.
“The opposition have not always been better than us in the league this season, but they have been more disciplined and we have got to learn the lessons quickly as a group and get better.
“Treviso will be keen to build on the momentum they have built up in recent weeks. There is no doubt that they are a very dangerous and well-drilled side.
“We will need a strong defensive effort, to show real structure to our game, know our roles and commit to them.”
