DISEASE: Alfalfa dwarf
HOST: Alfalfa
Alfalfa dwarf is characterized by stunted plants (left), usually dark blue-green in color. Xylem tissues become brown, especially when exposed to air.

Alfalfa dwarf | Alfalfa
DISEASE: Alfalfa dwarf
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Xylella fastidiosa
SOURCE: R. M. Davis
DISEASE: Pink disease
HOST: Pineapple
Infected pineapple slices; effect of heating (right) and not heating (left).

Pink disease | Pineapple
DISEASE: Pink disease
HOST: Pineapple (Ananas comosus)
PATHOGEN: Tatumella citrea
PATHOGEN SYNONYM: Pantoea citrea
SOURCE: K. Rohrbach, A. Alvarez
DISEASE: Pink disease
HOST: Pineapple
Two clones (A and D) showing different stages of infection. Second and fourth fruits (left to right) have been heated. Disease originally attributed to Gluconobacter oxydans and Enterobacter agglomerans and later to Pantoea citrea.

Pink disease | Pineapple
DISEASE: Pink disease
HOST: Pineapple (Ananas comosus)
PATHOGEN: Tatumella citrea
PATHOGEN SYNONYM: Pantoea citrea
SOURCE: K. Rohrbach
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