Northern root knot

Typical symptoms of attack include a galling of the root system, the galls being relatively small and subspherical, often with a marked proliferation of small roots at the site of the gall (this is in contrast to the symptoms caused by other common species of Meloidogyne). In potato tubers, brown spots appearing in the tubers after the females commence egg production may identify infection sites. Severe attack by M. hapla results in impaired root function and concomitant stunting of the above ground parts leading to a reduction in yield.