Pseudomonas syringae pv. phaseolicola

From Pestinfo-Wiki
Jump to: navigation, search

Literature database
127 articles sorted by:
year (recent ones first)
research topics
countries/regions
host plants
Pseudomonas syringae pv. phaseolicola symptoms on bean leaves (click on image to enlarge it)
Author(s): Howard F. Schwartz, Colorado State University
Source: IPM Images

Pseudomonas syringae pv. phaseolicola (Burkholder) Young, Dye & Wilkie - (halo blight of bean)

The pathovar is widespread on Phaseolus beans, peas, cowpeas and soybeans. Yield losses might reach 50%. The disease is seed borne and the bacterium can survive for more than 4 years in the seeds. It also spreads through rain splashes and epidemics can develop quickly under rainy conditions.

Pseudomonas syringae pv. phaseolicola symptoms on bean plant (click on image to enlarge it)
Author(s): Howard F. Schwartz, Colorado State University
Source: IPM Images

The bacterium enters the plant mainly through the stomata. Symptoms start with water-soaked lesions on the underside of the leaves which turn brown and develop broad greenish-yellow haloes. Pods, stems and petioles can also develop lesions. During moist conditions, bacteria might emerge from the lesions. Seedling infection leads to a general chlorosis, stunting and deformations. For management, pathogen-free seeds and resistant cultivars are recommended. Copper formulations and streptomycin can be also used.

P. syringae pv. phaseolicola is a gram-negative, aerobic, motile and rod-shaped bacterium. It is about 1½ µm long, with optimal growth at 25-30 °C. It reacts negative in oxidase and arginine dihydrolase tests, but forms levan and elicits the hypersensitive response on tobacco.

For reviews see Noble et al. (2019) and Arnold et al., 2011. For a summary on the species see Pseudomonas syringae.

Vernacular names
• Deutsch: Fettfleckenkrankheit der Bohne
• English: halo blight of bean
• Español: tizón del halo
• Français: maladie de la graisse du haricot

Synonyms:
Pseudomonas phaseolicola
Pseudomonas savastanoi pv. phaseolicola