DISEASE: Aster yellows
HOST: Aster
Foliar symptoms of chlorosis, malformation of leaves, and phyllody.
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Flowers with phyllody (left and center). Healthy flower (right).
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: R. McCoy, M. Davis
DISEASE: Aster yellows
HOST: Aster
Macrosteles sp., a leafhopper vector of aster yellows phytoplasma.
Aster yellows | Aster
DISEASE: Aster yellows
HOST: Aster (Aster sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: J. Clark, A. Purcell, M. Davis
DISEASE: Bacterial blight
HOST: Cassava
Leaf with angular, water-soaked, vein-delimited lesions.
Bacterial blight | Cassava
DISEASE: Bacterial blight
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas axonopodis pv. manihotis
PATHOGEN SYNONYM: Xanthomonas campestris pv. manihotis
SOURCE: A. Hayward
DISEASE: Bacterial blight
HOST: Cassava
Cassava with angular leaf spots and yellow ooze. Symptoms include leaf spots, wilt, and dieback. The bacterium frequently invades systemically.
Bacterial blight | Cassava
DISEASE: Bacterial blight
HOST: Cassava (Manihot esculenta)
PATHOGEN: Xanthomonas axonopodis pv. manihotis
PATHOGEN SYNONYM: Xanthomonas campestris pv. manihotis
SOURCE: A. Hayward
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: Bacterial leaf spot
HOST: Peanut
The disease causes water-soaked lesions, particularly on upper leaf surfaces. Lesions enlarge and later display brown necrotic areas. Leaflets become chlorotic and shed prematurely.
Bacterial leaf spot | Peanut
DISEASE: Bacterial leaf spot
HOST: Peanut (Arachis hypogaea)
PATHOGEN: Pseudomonas sp.
SOURCE: P. Subrahmanyam
DISEASE: Bacterial wilt
HOST: Peanut
First sign of disease is slight drooping or curling of leaves. As the plant declines, foliage turns yellow, followed by wilt and death of stems.
Bacterial wilt | Peanut
DISEASE: Bacterial wilt
HOST: Peanut (Arachis hypogaea)
PATHOGEN: Ralstonia solanacearum
PATHOGEN SYNONYM: Pseudomonas solanacearum
SOURCE: D. Porter