Question

What is the most popular white wine grape variety in the world?

Answer

Trebbiano, the famous white grape of Italy, is generally acknowledged as the most prolifically planted white grape variety. Although trebbiano is almost unknown in Australia, Campbells have produced a white wine from trebbiano since the late 1960’s winning several show medals with this variety.
Ref: Vines, Grapes and Wines – Jancis Robinson