Strawberry crimp nematode

Systematic position. The strawberry crimp nematode (Aphelenchoides fragariae) belongs to the phylum Nematoda, order Aphelenchida, and family Aphelenchoididae. It is a microscopic foliar nematode that lives as an endoparasite, primarily affecting the aerial parts of its host plants.

Host plants. This pest has a very broad host range. It is notorious for damaging strawberries, where it causes the characteristic "crimp" condition. It also infests numerous ornamental species, including ferns, begonias, African violets, lilies, and chrysanthemums, leading to stunted growth and severe foliage distortion.

Biology and life cycle. The nematode thrives in high-humidity environments, residing in leaf axils, buds, and young foliage. Its life cycle is rapid, often completing within 10 to 14 days under favorable warm and moist conditions, which allows populations to explode quickly during the growing season.

Damage and harmfulness. The feeding of Aphelenchoides fragariae causes twisted, crinkled, or brittle leaves, as well as darkened or necrotic areas. Infested plants exhibit reduced vigor, dwarfing, and shortened petioles. In strawberries, the nematode significantly reduces fruit yield and quality, often rendering the plants unfit for production.

Management and control. Controlling foliar nematodes is difficult due to their protected habitat inside plant tissues. Integrated pest management strategies include:

• Using only certified, disease-free planting stock.
• Implementing hot water treatment of nursery plants (e.g., 45-48°C for 10-15 minutes).
• Immediate removal and destruction of infested plants to prevent further spread.
• Avoiding overhead irrigation that creates the moisture films necessary for nematode movement.
• Maintaining strict sanitation practices in both field and greenhouse environments.