Helicotylenchus dihystera

Helicotylenchus dihystera is a species of nematode belonging to the family Hoplolaimidae. It is commonly known as the spiral nematode due to the spiral shape it assumes when at rest. This nematode is a plant-parasitic nematode, causing damage to a wide range of agricultural crops worldwide.

Morphology

The adult Helicotylenchus dihystera is characterized by its spiral shape when relaxed. It has a slender body, a rounded head, and a short, bluntly rounded tail. The cuticle is finely striated. The esophagus is divided into a short, muscular procorpus and a long, glandular postcorpus. The stylet is well developed, with basal knobs.

Life Cycle

The life cycle of Helicotylenchus dihystera includes egg, four juvenile stages, and adult. The nematode feeds on the roots of host plants, causing damage and potentially reducing crop yield. The female lays eggs in the soil or in root tissues. The eggs hatch into first-stage juveniles, which molt four times before becoming adults.

Host Plants

Helicotylenchus dihystera has a wide host range, including many economically important crops such as corn, potato, tomato, cotton, and banana. It can also infest various ornamental plants and turfgrasses.

Management

Management of Helicotylenchus dihystera involves a combination of cultural practices, biological control, and chemical control. Crop rotation with non-host plants can help reduce nematode populations in the soil. Biological control agents such as nematophagous fungi and predatory nematodes can also be used. Chemical nematicides are available, but their use should be limited due to environmental concerns.

See Also

• Plant-parasitic nematodes
• Nematode management