Prediction of stem rust infection favorability, by means of degree-hour wetness duration, for perennial ryegrass seed crops.

  title={Prediction of stem rust infection favorability, by means of degree-hour wetness duration, for perennial ryegrass seed crops.},
  author={William F. Pfender},
  volume={93 4},
  • W. Pfender
  • Published 1 April 2003
  • Biology, Medicine
  • Phytopathology
ABSTRACT A weather-based infection model for stem rust of perennial ryegrass seed crops was developed and tested using data from inoculated bioassay plants in a field environment with monitored weather. The model describes favorability of daily weather as a proportion (0.0 to 1.0) of the maximum possible infection level set by host and inoculum. Moisture duration and temperature are combined in one factor as wet degree-hours (DH(w)) (i.e., degree-hours > 2.0 degrees C summed only over time… 

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