AbstractObservations were made on the infection process of the temperate sedentary root-knot nematode, Meloidogyne hapla, into roots of Arabidopsis thaliana (L.) Heynh cv. Landsberg erecta in monoxenic culture . After invasion, the infective second-stage juveniles follow a similar migratory path as has been observed in other Meloidogyne species, moving toward and turning within the root tip, to invade the vascular system and initiate the permanent feeding sites. About a week after invasion, there was extensive production of roots at the feeding site and, about 1 week later, the formation of adventitious shoots was observed at about 4.5% of all galls formed. In comparison, very little root production and no shoot formation was found on feeding sites of M. incognita.