Halo blightCaused by: Pseudomonas savastanoi pv. phaseolicola
Problem Category: Bacterial Disease
Symptoms: Small water-soaked spots on underside of leaves which turn necrotic and become visible on upper surface; lesions may develop an area of chlorotic tissue around the spots; lesions on expanding leaves may cause distorted leaves; red-brown lesions may be visible on pods; pod lesions may ooze or may turn tan in color.
Comments: Bacterium survives in seeds and crop debris and enters plants through natural openings such as stomata and is spread by splashing water and soil movement.
Management: Plant disease free seed or treat seed with an antibiotic to reduce levels of bacterium; rotate crops to non-hosts every 2 years; plow bean debris deeply in soil after harvest.
Control: spray Buttermilk or Asafoetida solution to control the blight