HOST RANGE AND SYMPTOMATOLOGY OF VERTICILLIUM DAHLIAE IN ECONOMIC, WEED, AND NATIVE PLANTS IN INTERIOR BRITISH COLUMBIA

Abstract

Verticillium dahliae Kleb. has been isolated from 51 species of plants in 23 families. Eighteen species have not been recorded previously as hosts of Verticillium. Equisetum arvense L. (horsetail) is the first recorded host among non-flowering plants. The host species included many common weeds and native plants that can harbor the fungus during rotation periods for crop plants. Symptoms were not apparent on many of the plant species that yielded isolates. Inoculated plants of three weed hosts, purslane, lamb’s quarters, and penny cress, were less vigorous than uninoculated plants, although diagnostic symptoms were absent. Pathogenicity trials on tomato demonstrated the occurrence of numerous biologic forms or strains among the isolates.