RESULTS

(5)

FILTER

DISEASE: Brittle root

HOST: Horseradish

Dying, stunted, yellow to brown horseradish plants.

Brittle root | Horseradish

DISEASE: Brittle root

HOST: Horseradish (Armoracia rusticana)

PATHOGEN: Spiroplasma citri

SOURCE: C. Eastman, M. Davis

DISEASE: Brittle root

HOST: Horseradish

Close-up of stunted, yellow horseradish plants.

Brittle root | Horseradish

DISEASE: Brittle root

HOST: Horseradish (Armoracia rusticana)

PATHOGEN: Spiroplasma citri

SOURCE: D. Sherrod

DISEASE: Brittle root

HOST: Horseradish

Horseradish with discolored internal tissues. Healthy root segment (top right).

Brittle root | Horseradish

DISEASE: Brittle root

HOST: Horseradish (Armoracia rusticana)

PATHOGEN: Spiroplasma citri

SOURCE: J. Fletcher, M. Davis

DISEASE: Marginal leaf blight

HOST: Lettuce

Marginal leaf blight first appears as slimy wilting of leaf margins. Small, reddish lesions may be seen on leaf blades. Infected tissues turn brown to black in time.

Marginal leaf blight | Lettuce

DISEASE: Marginal leaf blight

HOST: Lettuce (Lactuca sativa)

PATHOGEN: Pseudomonas marginalis

SOURCE: L. Fucikovsky

DISEASE: Western wetwood

HOST: Elm

Spokelike, discolored extensions that expanded into sapwood, following an injection with a fungicide. The causal agent is not known but symptoms are associated with bacteria and yeast.

Western wetwood | Elm

DISEASE: Western wetwood

HOST: Elm (Ulmus americana)

PATHOGEN: Causal agent unknown

SOURCE: W. Sinclair