Xiphinema index

Xiphinema index is a species of nematode that belongs to the family Longidoridae. It is commonly known as the grapevine fanleaf virus vector due to its role in transmitting the Grapevine fanleaf virus (GFLV), a serious disease affecting grapevines worldwide.

Description

Xiphinema index is a long and slender nematode, with females typically measuring 2.5 to 3.5 mm in length. It is characterized by its long Odontostyle, a needle-like structure used for feeding, which is significantly longer than in other species of the same genus.

Distribution and Habitat

Xiphinema index is found in various parts of the world, including Europe, North America, Asia, and Africa. It is particularly prevalent in regions with a significant grapevine cultivation, such as the Mediterranean Basin and California.

The nematode prefers sandy or loamy soils and is often found in the root zone of grapevines. However, it can also be found in association with other plants, including fruit trees and ornamental plants.

Role in Disease Transmission

Xiphinema index is the primary vector of the Grapevine fanleaf virus, a Nepovirus that causes one of the most serious diseases of grapevines. The nematode acquires the virus when feeding on an infected plant and can retain it for a significant part of its life, transmitting it to other plants during subsequent feedings.

The disease causes a range of symptoms in grapevines, including yellowing and distortion of leaves, reduced yield, and in severe cases, death of the plant.

Control

Control of Xiphinema index and the Grapevine fanleaf virus involves a combination of strategies, including the use of resistant grapevine varieties, soil fumigation, and crop rotation. Research is ongoing to develop more effective and sustainable methods of control.

See Also

• Nematode
• Grapevine fanleaf virus
• Longidoridae