For viral sanitation strategy in Tunisia, citrus accessions from Washington navel (Citrus sinensis L. Osb.) variety were investigated for regeneration throughout direct and indirect in vitro organogenesis. In this study, either floral (style/stigma and ovaries) or vegetative organs (leaves, cotyledons, epicotyls and hypocotyls) were cultured into Murashige and Skoog (MS) culture media that were supplied with five different hormonal combinations of naphthalene acetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). An average of 12 repetitions/combination was adopted. The highest rate of callogenesis was evaluated as 95% which was obtained only from culturing style/stigma on MS media enriched with 3 mg.l-1 BAP, which resulted in 100% generated and 100% rooted plantlets. By acclimatization, a rate of 83% of the plantlets was successfully obtained. The major output afforded by this study is the highly successful regeneration of Washington navel sweet orange from style/stigma floral organs and using the appropriate media composition by contrast to the remaining studied explants in a sanitation and certification procedure. Key words: In vitro, organogenesis, style/stigma.

Keywords: In vitro, organogenesis, style/stigma.