Determining tomato diseases is not easy, as you will realize. Indeed, there are many diagnostic confusions. In order to put the odds in your favor, we recommend that you adopt the following procedure:

Carefully read the 3 themes of this sheet;

Choose plants with little developed symptoms and representative of the disease;

It is essential to recover whole plants, including their root system. Dig up the latter with great care and wash the roots.

Collect as much information as possible:

- on the disease (distribution in the plot, speed of development, climatic conditions preceding its appearance or seeming to favor its extension, etc.), its symptoms and signs (location on the plant, exact nature);
- on the plant (varietal characteristics, seed qualities, etc.);
- on the plot (location, characteristics of the soil, previous crops, addition of soil or manure, etc.);
- on the agro-cultural interventions carried out (fertilization, irrigation methods and frequency, quantity of water supplied each time, application of pesticides on or near the crop, etc.);
- on the culture environment.