Summary:
Potato late blight is a disease caused by a Phytophthora infestans that spreads rapidly in the potato crop canopy and can also infect tubers. The model determines when weather conditions create high risk of infection, to guide targeting of fungicide treatment. A high risk 'Hutton Criteria' period occurs when 2 consecutive days have a min temperature of 10°C and at least 6 hours of relative humidity at or above 90%. The model does not account for higher temperatures or humidity under crop covers.