Description, Biology, Life Cycle, Damage, Common Names, Images
The dagger nematode is highly polyphagous, basically on fruit trees and small fruit.
- Adult: these are migrant ectophytic nematodes which puncture the roots. They are mobile but are transported mainly by the wind, water or man.
- Separate sexes. The female lays eggs (20 to 30) mainly during April-May, occasionally later, in the ground, generally near the host plant. The female adult can live for 5 years, and can even survive for 3 years in the absence of the host plant.
- Juvenile: development, very slow, often extends over more than three years.
- One generation taking up to 3 years.
- Juveniles and adults cause damage. They puncture cell surface layers using their hollow stylets. They are capable of reaching to the xylem. The saliva toxins and enzymes soften vegetable tissue, the cellular layers are destroyed and slender roots die.
The result is a reduced root system and the proliferation of lateral roots, with hook-shaped deformation and tumours. At first, the damage appears mainly at feeding sites.
- During major attacks on strawberry, the damage causes stunting, and the plant dies. The attacked roots are grey-white.
- On large plants, growth is hardly affected; the viruses transmitted represents the main threat: AMV (arabis mosaic virus) on cherry, black currant, raspberry, strawberry, vine, hop and SLRV (latent spotted ring virus) on cherry, peach, plum, black currant, raspberry, vine, strawberry and hop.
- Rotation or fallow of a few years is recommended to avoid the risks of serious attack. The damage threshold is limited to a few individuals per cubic centimetre of soil.
The dagger nematode appears mainly on arable land, in deciduous woods and scrub. They prefer open soils which are neither too dry nor too sandy.
DE: Dolchälchen, Dolchnematode ES: Nemátodo migrador de las raíces FR: Nématode migrant des racines IT: Nematode migrante delle radici PT: Nemátodo migrador das raízes GB: Migrant root worm