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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.

Abstract Stinking passion flower (Passiflora foetida L.) is an herbaceous vine used due its medicinal properties. It could be an option to be used as a rootstock for sour passion fruit (P. edulis). This interest was especially motivated by its resistance to Fusarium oxysporum f. sp. passifloraeand F. solani, two soilborne pathogens that severely limit the sour passion fruit cultivation in Brazil. Phytonematodes are other important soil pathogens to most crops, including Passiflora species, and they often interact synergistically with pathogenic Fusarium spp. strains. However, the host status of stinking passion flower to phytonematodes was not assessed yet. Therefore, three pot experiments were carried out in order to assess the reproduction of Rotylenchulus reniformis, Meloidogyne javanica and on Pratylenchus brachyurusstinking passion flower and sour passion fruit. Both P. foetida and P. edulis were susceptible to R. reniformis, but immune (or highly resistant) to both M. javanica and P. brachyurus. Based on previous and the present work, R. reniformis stands out and could be pointed as the most important species to species of Passiflora.

Abstract In July 2020, during a survey carried out in a small farm located in Laranjal Paulista, state of São Paulo (Brazil), more than 20 white pitahaya plants [Hylocereus undatus (Haw.) Britton and Rose (syn. Selenicereus undatus (Haw.) D.R. Hunt] were found with stunting symptoms and showing chlorotic-yellowish stems, some of them already decaying. Roots exhibited numerous galls, indicating Meloidogyne sp. infection. Nematodes were recovered from 200 cm³ and 7 g of roots: 1.7 Meloidogyne juveniles (J2) per cm³ of soil and 954 eggs + J2 per g of roots were found. The perineal pattern of 10 females pointed to M. incognita. Additionally, esterase phenotype was obtained through isozyme electrophoresis, using another 10 females, which identified M. incognita. To our knowledge, this is the first report of M. incognita infesting pitahaya plants (Hylocereus spp.) and, based on our results, M. incognita could be a potential threat to the crop.