Phylloxera is an insect pest that is originally native to eastern North America, but today it attacks grapevines all over the world.
These tiny, pale yellow and sap-sucking insects are related to aphids, and they feed on the roots and leaves of grapevines. This results in deformations on roots (so-called nodosities and tuberosities) and fungal infections can girdle roots, gradually cutting off the flow of nutrients and water to the vine and thus killing it.
Phylloxera is found in most vineyards, yet thrives less in sandy and volcanic soils.
Currently there’s no cure for phylloxera, and the only successful means of controlling phylloxera is to graft phylloxera-resistant American rootstock onto more susceptible Vitis Vinifera vines.