DISEASE: Ash yellows
HOST: Ash
Ash sapling with basal sprouts and chlorotic leaves.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus pennsylvanica)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
Witches'-broom at base of declining tree.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus velutina)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
Forest of declining trees, some chlorotic and others with dieback.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus americana)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
White ash with deliquescent branching.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus americana)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Common scab (Potato scab)
HOST: Potato
Symptoms of common scab vary depending upon the cultivar. The lesions can be shallow or deep, erumpent and corky, and vary in color.

Common scab (Potato scab) | Potato
DISEASE: Common scab (Potato scab)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Streptomyces scabiei
PATHOGEN SYNONYM: Streptomyces scabies
SOURCE: A. Secor
DISEASE: Common scab (Potato scab)
HOST: Potato
White-skinned tuber with sunken and superficial scab lesions.

Common scab (Potato scab) | Potato
DISEASE: Common scab (Potato scab)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Streptomyces scabiei
PATHOGEN SYNONYM: Streptomyces scabies
SOURCE: S. Thomson
DISEASE: Common scab (Potato scab)
HOST: Potato
Red-skinned tuber with lesions that usually penetrate less than 1 mm.

Common scab (Potato scab) | Potato
DISEASE: Common scab (Potato scab)
HOST: Potato (Solanum tuberosum)
PATHOGEN: Streptomyces scabiei
PATHOGEN SYNONYM: Streptomyces scabies
SOURCE: S. Thomson
DISEASE: Sugar beet scab
HOST: Beet
Sugar beets with brownish, erumpent scabs.

Sugar beet scab | Beet
DISEASE: Sugar beet scab
HOST: Beet (Beta vulgaris)
PATHOGEN: Streptomyces scabiei
PATHOGEN SYNONYM: Streptomyces scabies
SOURCE: M. Shurtleff
DISEASE: Sweet potato little leaf
HOST: Sweet potato
Infected plant (left) and healthy plant (right).

Sweet potato little leaf | Sweet potato
DISEASE: Sweet potato little leaf
HOST: Sweet potato (Ipomoea batatas)
PATHOGEN: 'Candidatus Phytoplasma aurantifolia'
PATHOGEN SYNONYM: Phytoplasma Peanut witches'-broom group
SOURCE: R. McCoy, M. Davis