Mission Statement of the Nebraska Crop Surveillance Network:
Mitigate the impact of crop diseases and insect pests and safeguard Nebraska's agriculture against threats of bioterrorism.

Plant Disease: Pod and Stem Blight

Taxonomy:

Causal Agent: Fungus
Common Name: Pod and Stem Blight
Scientific Name: Diaporthe phaseolorum

Distribution:

  • World Wide

  • Common late-season disease.

Symptoms:

  • The most obvious sign of pod and stem blight is the presence of pycnidia on infected material.

  • Pycnidia are small, black fruiting structures are first seen on the petioles of shed leaves.

  • In linear rows formation on the stems.

  • This is one of the most definitive diagnostic features of this disease.

  • Lines of pycnidia may cover large sections of the stem or they may occur in clusters near the nodes.

  • Pycnidia can also occur in a scattered arrangement on the pods.

  • Infected seeds may appear healthy or they may be shriveled and cracked.

  • They are often covered with white mycelium. Severely infected seed may not germinate.

Management:

  • A rotation with corn reduces the amount of inoculum.

  • Incorporation of residue and soil will further reduce the inoculum in the debris.

  • Use a certified seed source as this disease will affect the % germination.

  • Use a seed treated fungicide, several are effective for Phomopsis Seed Decay.

Fungicide Application
  • Foliar fungicides may be applied to reduce the amount of Phomopsis seed decay.

  • This practice is only recommended for fields grown for seed production.

  • Benomyl (Benlate) and chlorothalonil (Supanil and Bravo) are labeled for control of Diaporthe pod and stem blight.

Notes: