Fusarium moniliforme syn. Fusarium verticillioides (Teleomorph: Gibberella fujikuroi)
Gibberella zeae (Anamorph: Fusarium graminearum)
Nature of damage
- Gibberella and Fusarium stalk rots can cause extensive crop damage by premature plant death, interference with translocation of water and nutrients during grain filling, and crop lodging.
Signs
- Symptoms produced by these pathogens resemble those caused by Stenocarpella or Cephalosporium, and cannot be differentiated until spore-producing structures are observed.
- Wilted plants remain standing when dry.
- Small, dark-brown lesions develop in the lowest internodes.
- When infected stalks are split, the phloem appears dark brown, and there is a general conspicuous browning of tissues.
- In the final stages of infection, pith is shredded and surrounding tissues become discolored.
Factors favoring development
- Fusarium moniliforme is most common in dry, warm areas. It is particularly severe if it begins just before tasseling.
- Gibberella zeae is prevalent in cool regions.
- Increased crop density and nitrogen fertilization rates favor disease severity.
- Crops under stress (e.g. due to foliar diseases) are more prone to stalk rots - stalks are already weakened as stalk sugars are diverted for grain filling.
Geographic distribution
- Maize growing regions worldwide.
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