A fuzzy growth is observed on the surface of the leaves, particularly during periods of high humidity. Fields should be monitored closely, particularly during prolonged cold wet weather, when the disease is more likely to occur. Fungicide applications should begin on plants two to three months old as soon as these conditions prevail. Downy mildew is seldom found in Texas as the season progresses into warmer weather. Pink root is strictly a soilborne disease.
Diseased roots turn pink in color, shrivel and die.
As the plant sends out new roots, they become infected and die. Affected plants do not usually die, but bulbs are small and of poor quality. The disease affects only roots. Plants infected with the pink root fungus will also develop the tip blight condition discussed previously. The fungus usually is introduced to new land by transplants grown in infected soil.