Fusarium oxysporum f. sp. radicis-lycopersici can attack seedlings tomato and cause their death . The disease is expressed mainly near the harvest; when the plants are loaded with fruit. Unlike vascular diseases in particular, wilting more or less severe appears on the leaflets and leaves at the top of the stem; in this zone, the rod is also strongly thinned. Depending on the plants, these wilts may initially be reversible during the night, and their incidence may fluctuate depending on climatic conditions. They can also be sudden, progress very quickly to necrosis and drying out of leaflets and leaves, and lead to the death of plants. Some authors also report the appearance of leaf yellowing located at the periphery of the blade of old leaves. These are followed by petiole necrosis and leaf drop. Some plants affected early see their growth reduced.

Regardless of the severity of wilting, the primary symptoms should be found on the roots and crowns of plants. On the former, both the cortex and the cylinder, reveal numerous reddish-brown lesions which , moist rapidly into develop rotting (figures 1 to 3). The smaller the diameter of the roots, the faster they rot and decompose. This is particularly the case in certain substrates of soilless crops in which they are very abundant.

A chancre frequently develops on the neck . It initially turns dark brown , and diseased tissue is more or less depressed (Figure 4). This chancre often evolves longitudinally, on one side of the stem, taking the form of a flame which can extend up to more than 30 cm above the neck (figures 5 to 6). The central part of the chancre takes on a pinkish salmon tint and a rather mucous appearance, due to the formation of sporodochia of the fungus (figure 7).

It should be noted that the vascular system also presents some symptoms, although we do not have to do with vascular disease. In general, the central cylinder of large roots reveals browning quite marked . It is the same for the vascular tissues of the pivot and those located on either side of the latter. The browning can be very marked and extend in the stem for several tens of centimeters above the collar (figure 8). Of adventitious roots sometimes develop on the stem.

The fruits of diseased plants are often slightly turgid and dull .