DISEASE: Bacterial decline
HOST: Papaya
Bacterial decline of papaya, historically called St. Croix decline, was thought to be caused by a fungus. This picture shows a papaya with dead top and side branches, a severe stage of the disease.

Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: M. Schroth
DISEASE: Bacterial decline
HOST: Papaya
Water-soaked papaya stem in St. Croix. Dark, water-soaked, greasy lesions occur on stems and leaves. The causal agent differs somewhat from descriptions of Erwinia papayae D strains in Micronesia.

Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: M. Schroth
DISEASE: Bacterial decline
HOST: Papaya
Bacterial invasion of leaf veins and adjacent tissues of papaya in Micronesia. This disease has also been called canker, dieback, and blight.

Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: E. Trujillo
DISEASE: Bacterial decline
HOST: Papaya
Complete destruction of papaya plantation in Micronesia. Only a severely damaged trunk remains.

Bacterial decline | Papaya
DISEASE: Bacterial decline
HOST: Papaya (Carica papaya)
PATHOGEN: Erwinia papayae
SOURCE: E. Trujillo
DISEASE: Hollow stalk
HOST: Tobacco
Hollow stalk may appear at time of topping and suckering. Top leaves wilt and the stalk becomes bare as the disease moves downward.

Hollow stalk | Tobacco
DISEASE: Hollow stalk
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: P. Shoemaker
DISEASE: Hollow stalk
HOST: Tobacco
Infection of flue-cured tobacco stalks occur at wound sites caused by topping. After top infection, browning of pith occurs and tissues rot.

Hollow stalk | Tobacco
DISEASE: Hollow stalk
HOST: Tobacco (Nicotiana tabacum)
PATHOGEN: Pectobacterium carotovorum
PATHOGEN SYNONYM: Erwinia carotovora subsp. carotovora
SOURCE: APS
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