Extension Plant Pathology at the University of Arizona


Diseases of olive ( Olea europaea ) in Arizona

Verticillium wilt

Verticillium wilt is caused by the soil borne fungus Verticillium dahliae.  Symptoms include wilt and death of one or several branches (photo 1) of infected trees.  In severe cases the entire tree may die.  In the low deserts of Arizona, symptoms develop in the early spring and are most severe in years with cooler temperatures in February through May.

The fungus infects the tree through the roots, grows into the xylem and causes blockage of the vascular system.  Substances produced in the plant during infection also may cause vascular discoloration, but this symptom is not always present.  This is not a root rot disease, so decay of the root tissues does not occur. 

Resistant rootstock of olive is available in trees for landscapes.  There is no effective treatment once plants are infected. 

1 wilt and death of olive brranches caused by verticillium wilt

 


Diseases of olive | Plant Disease Identification | Extension Plant Pathology


March 31, 2009


http://cals.arizona.edu/PLP/plpext/diseases/trees/olive/olivevert.htm