Root Knot (nematode
- Meloidogyne sp.): Root cracking is often associated with severe root
knot infection [Image]. Pitting and other surface
blemishes are also noted. Vines may be stunted and show nutritional deficiencies.
For diagnosis, split small, whip-like roots longitudinally and look for pearl-like
swollen female nematodes embedded in the flesh. Often the area surrounding the
nematode is dark. Nematodes may also be embedded in mature potato flesh but are
more easily viewed for diagnostic purposes in smaller roots. Small galls or swellings
can be detected on fibrous roots. Control options include crop rotation, resistant
varieties, nematicide treatments and careful selection of seed potatoes. Cut slips
above soil line to prevent transfer of infected roots to planting fields.
