Millions of dollars are spent each year to control this and related species. The Columbia root knot nematode is able to move only a few metres annually on its own, but it is spread readily through the transport of infested potatoes, in soil clinging to farm implements and in irrigation water. The potential impact of the Columbia root knot nematode on Canadian agriculture is so serious that areas in which the pest occurs are under federal quarantine, and no plant material from such quarantined areas may be imported into Canada. Root knot nematodes seriously affect root growth, yield and quality of potatoes. The above ground symptoms are not readily apparent, but they may consist of various degrees of stunting, lack of vigor, and wilting under moisture stress.
Infested roots have knot-like cysts that are readily identified.
Potato tubers may be heavily infected without showing external symptoms. In some cultivars, such as Russet Burbank, small raised galls or swellings appear on the tubers above the nematodes, and the internal tissue below the galls is necrotic and brownish. Galls may be solitary or bunched. Adult females are visible just below the surface as glistening white, pearl- shaped bodies surrounded by a brownish layer of tissue. The user of this information agrees to the terms and conditions in the copyright and disclaimer .