2,4-D na regeneração de Passiflora Edulis Sims. F. Flavicarpa Deg à partir de meristema apical

Abstract

Brazil is the largest producer of passion fruit. This fruit is of great importance for the country generating capital and jobs due to demand for labour. The culture presents problems with viruses that causes the woodiness effect in the fruit, leading to loss of quality and productivity. In this context, with the justification of obtaining a clonal cleaning protocol and a large-scale production of healthy seedlings in the future, the objective of this research was to test the effect of 2,4-D on regeneration of the apical meristem of adult plants of yellow passion fruit (Passiflora edulis f. flavicarpa Sims, Deg) in the culture medium. The shoot Apex were excised and desinfesteds to a length of 2 mm and the meristem cells were regenerated in culture Murashige and Skoog medium supplemented with different concentrations of 2,4-D (0.0, 0.6, 1.2, 1.8, 2.2, 2.4, 3.0, 3.6 and 4.2 mL L-1) and a fixed dose of 1.0 mg L-1 BAP in all treatments. The vials containing the meristem cells were incubated in the dark for 45 days. The cultures were then sub cultivated in MS for differentiation. The repricing was done every two weeks or as needed. Tissue regeneration development was very slow due to the small size of the meristem. Two diameters were evaluated - D1 and D2 - and the fresh mass (MF). It was found that there were significant differences between the means scores of dosages for the analyzed variables. In the Regression test, no models adjusted to the means observed, so the Scott-Knott test (5%) was used. It was concluded that the diameters are higher in doses of 0 mL L-1 and 1.8 mL L-1 of solution 2,4-D. For the fresh mass the doses that generated higher weights were those of 0.0, 2.2, 2.4, 1.2 and 4.2 mL L-1 showed statistically equal. Therefore, it is not recommended the use of 2,4-D for regeneration because the witness showed results similar and better than when there is presence of phyto regulator. However there is a need for further studies in relation to the use of 2,4-D on in vitro regeneration of passion fruit, due to little information about it.