Breath passion fruit (Passifloranitida) has been used as rootstock for sour passion fruit (P. edulis) in order to control wilting and collar rot caused by Fusarium spp. However, it is supposedly susceptible to root-knot nematode (Meloidogyne incognita), which is widespread in tropical crop fields. Two trials were carried out to assess the effect of M. incognitaon the growth of a P. nitida accession, and a third one was performed to assess the effect on the growth of P. edulisgrafted onto P. nitida and the anatomical changes induced by this nematode in P. nitida. In view of the high multiplication rate of this nematode in P. nitida, causing intense root galling and reducing plant growth of both P. nitida and P. edulis, P. nitida should not be used as rootstock, or even main crop, in M. incognita-infested fields.