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: Bacterial leaf spot
HOST: Larkspur
Infected leaflets with many purplish spots with necrotic centers.
Bacterial leaf spot | Larkspur
DISEASE: Bacterial leaf spot
HOST: Larkspur (Delphinium sp.)
PATHOGEN: Pseudomonas syringae pv. delphinii
SOURCE: R. Raabe
DISEASE: Bacterial leaf streak
HOST: Millet
Leaf with small, linear, water-soaked, reddish brown stripes.
Bacterial leaf streak | Millet
DISEASE: Bacterial leaf streak
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Xanthomonas campestris pv. pennamericanum
SOURCE: L. Claflin
DISEASE: Bacterial leaf streak
HOST: Millet
Advanced stage of disease.
Bacterial leaf streak | Millet
DISEASE: Bacterial leaf streak
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Xanthomonas campestris pv. pennamericanum
SOURCE: L. Claflin
DISEASE: Bacterial leaf stripe
HOST: Millet
Leaf with long reddish stripes, usually vein delimited.
Bacterial leaf stripe | Millet
DISEASE: Bacterial leaf stripe
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: L. Claflin
DISEASE: Bacterial leaf stripe
HOST: Millet
Leaf with reddish stripes delimited by veins.
Bacterial leaf stripe | Millet
DISEASE: Bacterial leaf stripe
HOST: Millet (Pennisetum glaucum)
PATHOGEN: Acidovorax avenae
PATHOGEN SYNONYM: Acidovorax avenae subsp. avenae
SOURCE: L. Claflin
DISEASE: Larkspur virescence
HOST: Larkspur
Two diseased plants with stunted and small leaves, lack of flower coloration, and bunched flower buds. Healthy plant (left).
Larkspur virescence | Larkspur
DISEASE: Larkspur virescence
HOST: Larkspur (Delphinium sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Raabe
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