Callogenesis and Morphohistological Characterization of Hancornia speciosa Gomes

Hancornia speciosa Gomes belongs to the family Apocynaceae and is distributed across different regions of Brazil. The objective of this study was to evaluate callus induction and histodifferentiation in five mangaba accessions under different in vitro culture conditions. Five acessions from the Active Germplasm Bank of Mangaba (Embrapa, Brazil) were evaluated. In vitro-germinated plant seedlings were used for the excision of different explants (internode and node segments, and foliar section). These segments were inoculated in a culture medium containing different concentrations of 6-Benzylaminopurine (BA) and 2,4-Dichlorophenoxyacetic acid (2,4-D). There was a significant effect of accessions, treatments, and time on the callus mass (g). There was no callus induction in the absence of regulators. After 60 days of in vitro culture, all treatments exhibited a linear positive cellular growth. The highest callus mass was observed in the BI accession, in the presence of 22.62 µM 2,4-D and 11.10 µM BA.