Causal Agent

Grapevine Fanleaf Virus (GFLV) 

 

Hosts

The natural host range of GFLV is Vitis species including V. vinifera, V. rupestris, and hybrids. 

 

Symptoms

Grapevine Fanleaf Virus (GFLV) is thought to be the most serious virus disease affecting grapevines. Fanleaf causes distortion of leaves and may cause unusual chlorotic (yellow) patterns on leaves such as a yellow mosaic or yellow veins. Plants that are infected with GFLV may be reduced in size compared to healthy plants. Fruit quality and winter hardiness are often reduced. Fruit losses of up to 80 percent have been reported in some varieties.The disease is spread by dagger nematodes, however, presence of the nematode is not required for infection in a vineyard since the virus is frequently spread by movement of infected plant material.

 

Control

Growers should plant certified, disease-free plants. Pruning tools should be disinfected with a bleach solution (1 part household bleach, 9 parts water) between cuts. Infected plants should be removed and discarded. Prior to replanting with susceptible hosts, a soil-test to determine the presence of plant pathogenic nematodes (which may harbor and spread the virus) should be performed.