DISEASE: Aster yellows
HOST: Marigold
Infected plant (left) with yellowing and stunting.

Aster yellows | Marigold
DISEASE: Aster yellows
HOST: Marigold (Tagetes erecta)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: M. Shurtleff
DISEASE: Deep bark canker
HOST: Walnut
Pits in the wood and black streaks in inner bark are key diagnostic symptoms.

Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia)
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad, M. Schroth
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Marigolds with yellow apical chlorosis attributed to toxin production by the pathogen.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin