Disease Triangle

A graphic, as a triangle, which represents the three key features which must be present for a disease to develop. The three features are:
1. Pathogen ¯ this might be present within the vegetation canopy, thatch or the soil;
2. Host ¯ species which are susceptible to the pathogen. The pathogen might affect a single species or many;
3. Environment ¯ conditions need to be favourable to the pathogen, which might include adequate moisture, soil pH, nutritional status of the soil, or temperature.