Verticillium Wilt

Verticillium wilt is a fungal disease of the tomato vascular system caused primarily by Verticillium dahliae. The pathogen penetrates the roots, colonizes the vascular tissues, and disrupts water transport. Symptoms include wilting and yellowing of the oldest leaves, sometimes initially on only one side of the plant; when the stem is cut open, brown discoloration of the vascular bundles may be visible. The fungus can survive for long periods in the soil in the form of microsclerotia and has many host plants. Control measures include using varieties resistant to the prevalent pathogen race, implementing hygiene practices to limit the spread of infected soil, and rotating crops with non-host plants.