Potato cyst nematode

Potato cyst nematodes (PCN) or potato root nematodes are 1-mm long roundworms belonging to the genus Globodera, which comprises around 12 species. They live on the roots of plants of the Solanaceae family, such as potatoes and tomatoes. PCN cause growth retardation and, at very high population densities, damage to the roots and early senescence of plants. The nematode is not indigenous to Europe but originates from the Andes. Fields are free from PCN until an introduction occurs, after which the typical patches, or hotspots, occur on the farmland. These patches can become full field infestations when unchecked. Yield reductions can average up to 60% at high population densities.

Identifying Features
PCN infestation causes plants to become stunted and they may wilt and have smaller, yellowish leaves. Affected plants have a reduced root system that shows abnormal branching and a brownish tint. Around flowering, minute white, yellow or brown spheres or cysts can be seen on the outside of roots. PCN reduces potential yields even in light infestations. Heavy infestations significantly reduce the size and number of tubers in potatoes.

Treatment
None.

Prevention
There are a number of precautions that can be taken to prevent the introduction and spread of PCN.
 * Plant certified seed purchased from recognised, certified-seed producers.
 * Avoid sharing equipment with other growers. The most common way of spreading PCN is in soil or on equipment.
 * Thoroughly clean all equipment moving off a property.
 * Practice crop rotation.
 * Arm yourself with information about the pest - its symptoms and appearance.
 * Regularly examine your crops for patches of poor or yellow potato plants.