Which strategy helped mitigate Phylloxera blight in vineyards?

• A. Matched climate to get grapes better
• B. Planted new root stock resistant to Phylloxera
• C. White wines in California
• D. Increased yields

Answer: (B)

Phylloxera attacks grapevine roots, so the solution is to shield the vines at the root level. By grafting European grape varieties (like many Vitis vinifera used for wine) onto rootstocks that come from American grape species, growers gain natural resistance. These rootstocks are not susceptible to Phylloxera, so the pest can’t feed on the roots and the vines survive and produce grapes. The above-ground variety remains the same, so winemaking style is preserved while the roots are protected.

The other options don’t address the root problem: changing climate doesn’t stop root-feeding insects, choosing white wines or locations doesn’t tackle the pest, and simply increasing yields stresses vines and can worsen vulnerability.