Estímulo do comportamento fotoautotrófico durante o enraizamento in vitro de Annona glabra L., I. desenvolvimento do sistema radicular e da parte aérea

Abstract

The objective of the present work was to evaluate whether Annona glabra L. shoots are able to acquire the photoautotrophic behavior during the in vitro rooting. In vitro A. glabra shoots originated from cultures in vessels sealed with cap and PVC film (culture without aeration), cap without PVC film or cotton tampon (cultures with aeration), were inoculated in WPM medium supplemented with 4.9 µ M IBA and 164,4mM activated charcoal in the presence (58.42mM) or absence of sucrose. During rooting, the same conditions in which shoots were induced were maintained. After inoculation, the tubes with explants were maintained in growth room under photosynthetic active radiation of 45-56 µ mol.m-2.s-1 and of temperature 25±3ºC. The results showed that the rooting of A. glabra shoots do not depend on the supply of sucrose into culture medium, in vessel with aeration. Aeration of cultures brought expressive increments of dry weight of roots (up to 250%). The induction of secondary (side) roots was found only in cultures with aeration, independently of sucrose presence. One concluded that the acquisition of the photoautotrophic behavior in A. glabra may be obtained with success during the in vitro rooting phase.