DISEASE: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.
Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Multiplier disease
HOST: Strawberry
Multiplier disease causes production of numerous crowns along runners.
Multiplier disease | Strawberry
DISEASE: Multiplier disease
HOST: Strawberry (Fragaria × ananassa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: M. Clark
DISEASE: Rugose leaf curl
HOST: Clover
Two rugose, distorted white clover leaves and a healthy leaf. Rugose leaf curl is caused by an unidentified phloem-infecting bacterium.
Rugose leaf curl | Clover
DISEASE: Rugose leaf curl
HOST: Clover (Trifolium repens)
PATHOGEN: Phloem-infecting bacterium
SOURCE: D. Teakle
DISEASE: Witches'-broom
HOST: Alfalfa
Alfalfa plant (center) exhibiting stunting and proliferation of stems. Other symptoms are small, rounded, chlorotic, often puckered leaves and a yellowish cast.
Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Alfalfa
Young plant (left) with small, numerous stems (witches'-broom). Healthy stems (right).
Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson