Turner said: "It's a must-win match for us. We'll have to be prepared but we know it will be a physical encounter. It's just a pity we couldn't go there on the back of a win."
A spirited Dragons performance pushed Gloucester all the way despite two late blunders by stand-in captain Ceri Sweeney in their narrow EDF Energy Cup 13-11 defeat.
Although Turner didn't single Sweeney out for criticism, he will know Sweeney's late kick for goal and turnover with just minutes remaining proved to be fatal for the Dragons as the Guinness Premiership leaders snatched victory.
Turner added: "I felt we should have won but it's disappointing that we made poor decisions with two minutes to go - it's a harsh lesson for us and a real kick in the teeth to lose so late.
"We simply have to go to Treviso and win. A lot of teams have made the mistake of trying to get the bonus-point and have ended up losing."