Pratylenchus which can do direct damage to roots.
“In Norway anecdotal evidence has been found of an association between
Pratylenchus and common scab caused by
Streptomyces
scabies.
“It appears in the lesions caused by the scab, but we do not know whether it is a cause or an effect.”
Other work in North America suggests that the nematode creates wounds when feeding on the roots, opening a way for Verticillium to enter. [Identification and distribution of root lesion nematodes]
Roy said: “One of the challenges is that changing one pathogenic nematode population affects the balance of the whole cycle, so strategies which will mitigate the parasitic effects without compromising the beneficials are called for.