Plant regeneration of sweet orange (Citrus sinensis) from thin sections of mature stem segments

An efficient system for in vitro plant regeneration from thin transversal stem sections explants (1–2 mm) using mature tissues of sweet orange cv. Pera was developed. Explants were cultured in different media to evaluate the frequency of regeneration and size of buds. A high percentage of explants (54% with 3.1 buds/explant) producing large buds (1–4 mm) was observed when the explants were cultivated for 2 weeks on Murashige and Skoog medium and then transferred to Woody Plant medium (WPM). Both media were supplemented with 1.8 M 6-benzylaminopurine and 0.7 M gibberellic acid. Adventitious buds were regenerated into whole plants by in vitro shoot-tip grafting. Regenerated plants started to flower after 12 months in the greenhouse, confirming their mature nature.