Polysora rust

Puccinia polysora

Nature of damage

  • Damage is caused by loss of photosynthetic leaf area, chlorosis, and premature leaf senescence leading to incomplete grain filling and poor yields.

Signs

  • Pustules emerge predominantly on the lower leaf surface, but also occur on the stem and sheath.
  • They are orangish in color, circular, and raised.

Factors favoring development

  • Periods of extended dew or high humidity.
  • In temperate regions, Polysora rust is more prevalent towards the end of the growing season when temperatures rise.
  • Late planted and late maturing maize.

Geographic distribution

  • Tropical and subtropical maize growing regions worldwide.
  • In some seasons characterised by warm growing conditions, Polysora rust can become a major constraint to maize production in temperate regions.

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