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: Black rot
HOST: Broccoli
Blight and rot of flower buds.
Black rot | Broccoli
DISEASE: Black rot
HOST: Broccoli (Brassica oleracea var. italica)
PATHOGEN: Xanthomonas campestris pv. campestris
SOURCE: M. Shurtleff
DISEASE: Oak leaf scorch
HOST: Oak
Leaf with brown, marginal necrosis resembling a burn.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Oak leaf scorch
HOST: Oak
Diseased tree with brownish, scorched leaves.
Oak leaf scorch | Oak
DISEASE: Oak leaf scorch
HOST: Oak (Quercus rubra)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
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
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Chlorotic leaves with total loss of chlorophyll. Disease is also known as toxic chlorosis.
Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes erecta)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin