Scientific Name

Phytophthora parasitica

Overall Plant Symptoms

Damping off of seedlings. Weak plant appearance. Collapse in area of field follows highest soil water retention or flooding.

Leaf Symptoms

Water stressed appearance from lack of root activity.

Stem Symptoms

Simple desiccation from moisture loss. Another species of soil-borne phytophthora, P. capsici can attack stems under high moisture, especially in fields rotated with peppers.

Root and Fruit Symptoms

Root: water-soaked lesions; chocolate brown xylem above the lesion and into the crown. Tap roots often rotted.

Disease Source

Infested soils.

Source Peristence

Long lived organism with a very wide host range.

Favoring Conditions

Heavy soils saturated for five hours or longer, compacted soils, salinity, and some varieties.

Critical Crop Time

Warm season, but plant collapse more common as crop loads increase.

Controls/Management

Soil preparation, deep ripping. Water management with frequent shallow irrigations on heavy soils.

Additional Notes

Most common in turn areas and irrigation drains.