Anatomical and histochemical studies of the somatic embryogenesis of Syagrus oleracea from immature inflorescences
Inaê Mariê de Araújo Silva-Cardoso, Filipe Sathler Meira, Ana Cristina Meneses Mendes Gomes and Jonny Everson Scherwinski-Pereira
Abstract: Anatomical and histochemical studies were carried out during the somatic embryogenesis of Syagrus oleracea (Mart.) Becc. from immature inflorescences. Immature rachillas were inoculated on Murashige and Skoog medium with 4.52 μM 4-amino-3,5,6-trichloropicolinic acid (Picloram) and 2,4-diclorophenoxyacetic acid. Auxin concentrations were gradually reduced for the formation of somatic embryos, while for plantlet regeneration, embryos were inoculated on a medium without growth regulator. After 270 days, two types of embryogenic calluses were observed in explants under the effect of Picloram: nodular, with a smooth surface and those without definite shape, with an irregular surface, both presenting a meristematic zone with polysaccharide content. Callus progression to the differentiation stage allowed for the conversion of somatic embryos, some with a well-defined protoderm and procambial bundles. The histochemical analysis of the somatic embryos did not identify the presence of polysaccharide and protein reserves, which emphasizes the necessity for optimization of the maturation conditions.