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: Maize bushy stunt
HOST: Corn (Maize)
Maize with chlorotic leaf margins and reddening of tips and margins of older leaves.

Maize bushy stunt | Corn (Maize)
DISEASE: Maize bushy stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. Nault, M. Davis
DISEASE: Maize bushy stunt
HOST: Corn (Maize)
Late stage of disease.

Maize bushy stunt | Corn (Maize)
DISEASE: Maize bushy stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. Davis, M. Davis
DISEASE: Maize bushy stunt
HOST: Corn (Maize)
Dalbulus maidis, leafhopper vector of 'Candidatus Phytoplasma asteris', the cause of maize bushy stunt.

Maize bushy stunt | Corn (Maize)
DISEASE: Maize bushy stunt
HOST: Corn (Maize) (Zea mays)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: L. Nault, M. Davis
DISEASE: Phytoplasma disease
HOST: Gayfeather
Gayfeather with phyllody of flowers.

Phytoplasma disease | Gayfeather
DISEASE: Phytoplasma disease
HOST: Gayfeather (Liatris 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
DISEASE: Pseudomonas leaf spot
HOST: Marigold
Plants with bright yellow apical chlorosis.

Pseudomonas leaf spot | Marigold
DISEASE: Pseudomonas leaf spot
HOST: Marigold (Tagetes patula)
PATHOGEN: Pseudomonas syringae pv. tagetis
SOURCE: R. Durbin
DISEASE: Tomato big bud
HOST: Tomato
Characteristic symptoms are swollen, apical stems and stunted leaves. Apical stems are generally thickened and assume a stiff and erect growth habit. Internodes are shortened and flower buds are greatly enlarged.

Tomato big bud | Tomato
DISEASE: Tomato big bud
HOST: Tomato (Lycopersicon esculentum)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: D. Teakle