Cytokinin and Auxin on In vitro Multiplication of Yellow Passion Fruit

Aims: The objective of this research was to evaluate the effect of growth regulators on in vitro multiplication of Passiflora edulis f. flavicarpa.

Study Design: The experimental design was completely randomized in a factorial 5x2 (BAP x presence or absence of NAA) with six replicates, each consisting of a bottle with four explants.

Place and Duration of Study: The study was conducted at the Fruit Plant Propagation Laboratory, Federal University of Pelotas, RS, Brazil. After 60 days of cultivation, the number of leaves, shoots, average shoot length (cm), average number of roots and average length of roots (cm) were evaluated.

Methodology: The Stem segments with a shoot were inoculated on MS medium adding or not growth regulators 6 - benzylaminopurine (BAP) (0.5, 1.0, 1.5, 2.0 and 2.5 mg L-1) and naphthalene acetic acid (NAA) (0 and 0.1 mg L-1), according to the treatment. Then, they were kept in a growth chamber.

Results: The length of shoot and longest root, and root number were lower in the presence of BAP and NAA than the control (without BAP and NAA). BAP at 0.5 mg L-1 without NAA showed the highest number of leaves and the same dose of BAP with NAA, irrespective of the combination of NAA, showed the highest number of shoots of P. edulis f. flavicarpa on in vitro multiplication.

Conclusion: Cytokinin at low concentration is suitable for the proliferation of shoots and development of leaves. However, cytokinin and auxin are not preferred to the differentiation and growth of the roots. Yellow passion fruit might be efficiently multiplied by using different media for propagation of shoots and differentiation of roots, respectively.