Pyrenochaeta lycopersici mainly attacks the root system of the melon. The particularly sensitive rootlets turn brown, degrade quickly and disappear. The roots locally reveal superficially corky lesions on the cortex, gradually surrounding the roots, which eventually show a few cracked, dry-looking sleeves (Figures 1 and 2).

In general, the plants attacked have a more or less reduced root system.

Root damage has the consequence of reducing the development of plants, which remain more or less stunted. The leaves lower chlorinate, wilt  and dry out (Figure 3) during hot periods of the day, but may also regain their turgor during the night.