Symptoms and Signs
Symptoms first appear as stunting and reduced tillering early in the growing season. Later, infected plants prematurely form white heads that lack grain. Roots and crowns are darkened. The presence of a layer of dark brown or black fungal mycelium underneath the lowest leaf sheaths distinguishes take-all from common root rot.
Comments on the Disease
The fungus survives on crop residue and on roots of certain grass weeds, including bentgrass, quackgrass, and some species of brome. When soil moisture is high, the fungus spreads to adjacent plants by root contact. Infection is favored by cool weather. Take-all is more severe in plants grown on alkaline soil or soil deficient in nutrients.
Management
Cultural Control
Take-all infects wheat, barley, oats, and rye, but strains of this pathogen are host specific. Thus, the strain that infects wheat is not the same strain that infects oats. Rotate to a nonhost species and manage grassy weeds and volunteers. Improve field drainage and provide optimum soil fertility.
Chemical Control
No fungicide applications are recommended for this disease.
Text Updated: 04/26