Plant disease forecasting

At the field scale, these systems are used by growers to make economic decisions about disease treatments for control.

Often the systems ask the grower a series of questions about the susceptibility of the host crop, and incorporate current and forecast weather conditions to make a recommendation.

[1] The objective is to accurately predict when the three factors – host, environment, and pathogen – all interact in such a fashion that disease can occur and cause economic losses.

In most cases the host can be suitably defined as resistant or susceptible, and the presence of the pathogen may often be reasonably ascertained based on previous cropping history or perhaps survey data.

[6] USPEST.org graphs risks of various plants diseases based on weather forecasts with hourly resolution of leaf wetness.

[4] The costs of these two types of errors need to be weighed carefully before deciding to use a disease forecasting system.