The effects of inoculation with arbuscular mycorrhizal fungi (AMF), of soil sterilization, and of phosphorus fertilization on growth of yellow passion fruit were evaluated in greenhouse conditions. The experimental outlay was a completely randomized 2 × 3 × 4 factorial design with three replicates per treatment. The applied treatments, using 1.6 dm³ pots, were: two soil treatments (sterilized-SS and unsterilized soil-US), three P treatments (soil with 4, 11 and 30 mg dm-3 of P) and four AMF treatments (inoculation with either Gigaspora albida or Scutellospora heterogama, with mixed inoculum of G. albida, G. margarita, Acaulospora longula and S. heterogama and an uninoculated control). Inoculated seedlings cultivated in SS presented significant increases of height, stem diameter, number of leaves and claspers after the 50th day of inoculation (d.a.i.), except for S. heterogama, which promoted late host responses (70th d.a.i.). Higher root colonization and spore density on the rhizosphere were registered in SS. Only in the control and S. heterogama treatments P shoot concentrations were negatively affected by soil sterilization. In general, soil sterilization, P supply, and AMF inoculation enhanced the growth of yellow passion fruit. Interactions of mycorrhizal inoculation with soil sterilization and with phosphorus were observed.
endomycorrhizal fungi; phosphorus; Acaulospora longula; Gigaspora albida; Gigaspora margarita; Scutellospora heterogama