DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava
Cassava with yellowish leaves and water-soaked, angular spots. The disease is primarily on foliage, although the pathogen may invade stem buds and young branches.
Bacterial leaf spot (Bacterial necrosis) | Cassava
DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas cassavae
PATHOGEN SYNONYM: Xanthomonas campestris pv. cassavae
SOURCE: APS
DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava
Cassava with brownish lesions and blackish edges. Leaves turn yellow with multiple infection sites.
Bacterial leaf spot (Bacterial necrosis) | Cassava
DISEASE: Bacterial leaf spot (Bacterial necrosis)
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas cassavae
PATHOGEN SYNONYM: Xanthomonas campestris pv. cassavae
SOURCE: H. Maraite, A. Alvarez
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from longitudinal cracks in the trunk. Cankers are deep extending into wood.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale
DISEASE: Deep bark canker
HOST: Walnut
Reddish brown exudate flowing from cracks in trunk, a result of systemic invasion by the bacterium.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: B. Teviotdale
DISEASE: Deep bark canker
HOST: Walnut
Pits in the wood and black streaks in inner bark are key diagnostic symptoms.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia)
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad, M. Schroth
DISEASE: Deep bark canker
HOST: Walnut
Removal of bark revealed pitted vascular tissues.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad
DISEASE: Deep bark canker
HOST: Walnut
Dead limbs are characteristic of advanced stage of disease.
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad
DISEASE: Lethal yellowing/scorch
HOST: Beet
Blue-green sharpshooter (Graphocephala atropunctata) transmits Xylella fastidiosa and has a large host range, including palms, grasses, and grapes.
Lethal yellowing/scorch | Beet
DISEASE: Lethal yellowing/scorch
HOST: Beet (Beta vulgaris)
PATHOGEN: Xylella fastidiosa
SOURCE: A. Purcell, M. Davis