Puccinia striiformis Infection Model

Puccinia striiformis is the wheat rust of cool climates having its optimum temperature already from 15°C on. Its infections are taking place after for some hours of leaf wetness at optimum temperature conditions. The fungus can infect over a wide range of temperatures. The model assumes that infection needs an accumulated hourly air temperature of 80°C of leaf wetness in a air temperature range from 5°C to 20°C. There are no infections in periods with low light intensities.

  • Leaf wetness and light for accumulated hourly average temperatures for 80°C
    • (if T <= 15°C then ∑(Th) else ∑ Th-15?/li>
    • 5°C < Temp. < 20°C

In FC an infection with P. striiformis is shown on August 23nd after a long leaf wetness period at temperatures around 15°C  (red line). After that infection curative plant protection strategies have to be taken into account (systemic), while before infection has reached 100% protective application could be done.