Grape - Top producers of grapes for wine making, by area planted

There are no reliable statistics that break down grape production by variety. It is believed that the most widely planted variety is Sultana, also known as Thompson Seedless, with at least 3,600 km2 (880,000 acres) dedicated to it. The second most common variety is Airén. Other popular varieties include Cabernet Sauvignon, Sauvignon blanc, Cabernet Franc, Merlot, Grenache, Tempranillo, Riesling, and Chardonnay.[10]

Reference 1: Area (km²).

Reference 2: Spain, France, Italy, Turkey, United States, Iran, Romania, Portugal, Argentina, Chile, Australia and Armenia.

Source: http://en.wikipedia.org/wiki/Grapes