Nacobbus aberrans False root-knot nematode Damage to Sugar beets.  With high populations of the false root-knot nematode, the sugarbeet storage root is distorted and deformed, and the top growth of this plant is greatly reduced. Biology.   Nacobbus aberrans  is an endoparasitic species with sedentary, swollen females inhabiting galls which they induce in the roots of their hosts. Ecology.  N. aberrans is indigenous to the Americas. Approximately 1/3 of the sugarbeet fields in western Nebraska were infested with N. aberrans.  This nematode has also been found on sugarbeet in limited areas in Colorado, Kansas, Montana, South Dakota, and Wyoming. Symptoms.  Stunting, chlorotic leaves with rolled margins, and wilting. Nematodes in the genus Nacobbus produce galls that are similar in appearance to those caused by root-knot nematodes.  If diagnosis is primarily based on field symptoms, it is often erroneously assumed that crop damage caused by Nacobbus species is due to Meloidogyne species.  For this reason, Nacobbus species are referred to as false root-knot nematodes.  Damage to other crops.  Nacobbus aberrans is also a  parasite of  bean, chili pepper and tomato. Control.  References.  Sugarbeet Nematodes (UC Pest Management Guidelines