Plant Pathology Infobytes
September 04, 1996
What's Wrong With My Strawberry Plants?
Home fruit growers with wilted and dying strawberry plants may be running into black root rot, a disease which often appears in late summer.
Black root rot may be confined to a few plants, but more often this disease is widely distributed and causes problems over an entire planting. Strawberry plants affected by black root rot are less vigorous than normal, produce fewer runners, and are often killed by the disease.
The best way to identify black root rot is to look for plants which are showing symptoms of wilting. Carefully dig a plant and examine the root system. A plant with black root rot will exhibit one or more of the following root symptoms:
- The root system will be smaller than in normal plants.
- The number of feeder roots will be reduced; also, feeder roots will be discolored and have an unthrifty appearance.
- The main root will be dark brown or black.
A combination of factors is thought to be responsible for black root rot. For example, root rot fungi such as Pythium, Fusarium, and Rhizoctonia are associated with the problem, and plants which have been weakened by nematode feeding, winter injury, fertilizer burn, drought, poor soil drainage, and other unfavorable growing conditions are more susceptible to black root rot attack. Irrigated plantings of strawberries generally have less black root rot than non-irrigated fields.
Black root rot can not be cured once the disease has been detected. Control measures should be taken ahead of time to reduce the chances for development of this problem.
- Use only healthy, white-rooted strawberries when planting.
- Plant in well-drained soils.
- Maintain plant vigor by following recommended fertilization, watering, and cultivation guidelines, since stronger plants are less susceptible to black root rot.
Infobytes newsletter was written by the late Dr. Frank Killebrew, Extension Specialist.