Bean IPM

Legume ipmPIPE Diagnostic Series

Bacterial Wilt

Curtobacterium flaccumfaciens pv. flaccumfaciens

Figure 1 – Wilting or flaccid leaves, interveinal chlorosis and necrosis on upper and lower leaf surfaces; small water-soaked areas may be visible on lower surface.

Figure 2 – Necrotic areas may become more golden brown with age and water-soaked areas are more difficult to detect, dead leaves may remain attached to plants.

Figure 3 – Elongated, water-soaked and necrotic lesions may form on stems, petioles and occasionally pod sutures.

Factors favoring
  • Infected seed, infested debris and volunteers from previous seasons
  • Rainstorms, hail damage and sprinkler irrigation
  • Warm temperatures with daily highs less than 32°C [90°F]
Lesions on leaves
Figure 1
Decaying leaves hanging on stems
Figure 2
Dead leaves and lesions on stems
Figure 3

H.F. Schwartz, Colorado State University, M.A.C. Langham, South Dakota State University, R.M.Harveson, University of Nebraska, and G.D. Franc, University of Wyoming

Photo credits

H.F. Schwartz, Colorado State University