What is phylloxera?

What is phylloxera?

• A. An aphid that feeds on leaves.
• B. A beetle that tunnels into grape skins.
• C. A fungus infecting roots.
• D. An aphid that feeds on rootstocks.

Answer: (D)

Phylloxera is a tiny aphid-like insect that targets grapevines, with the most damaging form feeding on the roots rather than the leaves. This root-feeding habit on the rootstocks causes root damage, reducing water and nutrient uptake and often killing vines if unchecked. That’s why the best description is an aphid that feeds on rootstocks. It’s not a beetle, and it’s not a fungus. While some leaf-feeding forms exist on certain wild grape species, the historic and defining damage comes from roots feeding on the vine’s rootstock, which is why grafting Vitis vinifera onto resistant American rootstocks became the standard solution.

Phylloxera is a tiny aphid-like insect that targets grapevines, with the most damaging form feeding on the roots rather than the leaves. This root-feeding habit on the rootstocks causes root damage, reducing water and nutrient uptake and often killing vines if unchecked. That’s why the best description is an aphid that feeds on rootstocks. It’s not a beetle, and it’s not a fungus. While some leaf-feeding forms exist on certain wild grape species, the historic and defining damage comes from roots feeding on the vine’s rootstock, which is why grafting Vitis vinifera onto resistant American rootstocks became the standard solution.