DISEASE: Oleander leaf scorch
HOST: Oleander
Diseased plant with scalloped, yellowish leaves. This usually is followed by dieback of twigs and branches. Plants often die 2 years after infection.

Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: S. Purcell
DISEASE: Oleander leaf scorch
HOST: Oleander
Oleander with symptoms of severe scorch.

Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: M. Blua
DISEASE: Oleander leaf scorch
HOST: Oleander
Oleander with scorch symptoms primarily at leaf tips, an early stage of disease.

Oleander leaf scorch | Oleander
DISEASE: Oleander leaf scorch
HOST: Oleander (Nerium oleander)
PATHOGEN: Xylella fastidiosa
SOURCE: M. Blua
DISEASE: Sour skin
HOST: Onion
Symptoms of sour skin are characterized by slimy, pale yellow to light brown decay.

Sour skin | Onion
DISEASE: Sour skin
HOST: Onion (Allium cepa)
PATHOGEN: Burkholderia cepacia
PATHOGEN SYNONYM: Pseudomonas cepacia
SOURCE: Dep. of Agric. & Agri-Food, Government of Canada
DISEASE: Sour skin
HOST: Onion
Characteristic pale yellow to browning of infected area.

Sour skin | Onion
DISEASE: Sour skin
HOST: Onion (Allium cepa)
PATHOGEN: Burkholderia cepacia
PATHOGEN SYNONYM: Pseudomonas cepacia
SOURCE: R. Gitaitis
DISEASE: Xanthomonas leaf blight
HOST: Onion
This was the first photo of onion leaf blight, which was considered a controversial finding for 10 years until an outbreak occurred in the West Indies.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Diseased leaf with necrotic internal tissues.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: A. Alvarez
DISEASE: Xanthomonas leaf blight
HOST: Onion
Onions with brown, necrotic, blighted leaves.

Xanthomonas leaf blight | Onion
DISEASE: Xanthomonas leaf blight
HOST: Onion (Allium cepa)
PATHOGEN: Xanthomonas axonopodis pv. allii
PATHOGEN SYNONYM: Xanthomonas campestris pv. allii
SOURCE: H. Schwartz