Nematodes cause the root system to be impaired, often resulting in the progressive decline and death of strawberry plants. Root impairment also makes strawberries much more susceptible to drought conditions and injury from fertilizer salt accumulation.
Strawberries are susceptible to multiple nematode species. The most common and financially devastating pests to strawberries in the United States are sting nematodes and northern root-knot nematodes.
In addition to monitoring visual plant symptoms, collecting soil samples is an effective method to determine if you have nematodes.
Nematodes are most often evident in transplants that fail to grow-off normally. Symptoms of nematode damage usually occur in variously-sized, but definite areas or spots within a field. Areas of affected strawberries will fail to develop properly, and fruit quality will decline if nematode populations continue to increase with crop growth.
Plant damage ranges from mild to moderately progressive browning of the leaves, to severe stunting of the plant with little or no new plant growth. As outer leaves die, the plant gradually decreases in size, leaving the plant more susceptible to other diseases. As a result, the entire plant may eventually die.
The following is a list of common aboveground symptoms of nematode damage in strawberries:
- Patches of poor growth in the field
- Leaf browning
- Foliar crimping
- Outer, older leaf death
- Reduction in flowering and fruiting
- Reddened leaves
- Lack of response to treatment for other problems
The following is a list of common belowground symptoms of nematode damage in strawberries:
- Root abnormalities
- Lack of feeder roots
- Root galls
- Stubby roots
- Dead root tips
- Coarse roots
Confirmation that nematodes are present can be determined through soil samples.