Bacterial Brown Spot of Beans and Peas

Pseudomonas syringae pv. syringae

Description:

A bacterial disease of Beans that shows as small round reddish spots on leaves that are often surrounded by a halo of lighter green tissue. The spots may become somewhat angular as they encounter veins in the leaf. The centre of the spots often dry and fall out leaving a hole in the leaf and the leaf often tears from spot to spot. On stems, brown, sunken spots with reddish edges and about 1 cm diameter may form. On pods, sunken brown spots with a water soaked appearance may occur and bacteria from these may infect the seed.

Species Affected:

Beans. French Bean and Kidney Bean are very susceptible.

Biology:

Infection often occurs where sand blasting, frost or Rust has damaged the plants.
Favoured by cool showery weather.
Bacteria transferred between plants by raindrop splash and wind driven rain.
Bacteria can survive on Bean debris in the soil for over year.

Life Cycle:

Origin and History:

Distribution:

Significance:

Management and Control:

Use healthy seed.
Plant resistant varieties.
Don't work in infected crops when they are wet.
Remove and destroy diseased plants.
Rotate to resistant species.
Destroy crop residues.

Related and Similar Species:

References:

1291

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.HerbiGuide.com.au for more information.