A study was done with 4 sweet-orange cultivars, by the utilization of the same somatic tissue taken from two sources, namely an original old clone and its nucellar clone, in the obtention of Citrus plants. It was observed that nucellar buds had one influence on the vigour of the new plants and on the juvenility expression through presence of thorns. It was confirmed that the thorn presence is connected with the juvenil phase and not with the vegetative vigour.