Diseased stems weakened at their base may occasionally lodge, or lie flat on the ground. Although these symptoms are often the first obvious indications of Take-all, they are the terminal stages of the disease. The Take-all fungus survives from year to year on the undecomposed root and crown residue of infected plants. It can be spread from area to area in this debris. Healthy plant roots become infected as they grow through soil near infected wheat debris.
Infection occurs when the fungus penetrates the young roots of a living plant.
Infection occurs throughout the growing season but is more severe when the temperature is between 54 degrees and 64 degrees F. Damage is usually greater when plants are infected in the autumn or early spring. Damage may not be visible when plants are infected in late spring rather than early spring. Wet soils, especially during the second half of the growing season, favor Take-all development. Symptoms are less noticeable under dry soil conditions. Take-all severity on wheat depends on the supply of nutrients to the host.