Obtenção e manutenção de linhagens embriogênicas in vitro a partir de embriões zigóticos em famílias de Acrocomia aculeata

• Ano de defesa: 2014
• Autor(a) principal: Granja, Manuela Maria Cavalcante
• Orientador(a): Motoike, Sérgio Yoshimitsu
• Banca de defesa: Carvalho, Mychelle , Otoni, Wagner Campos
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Genética e Melhoramento
• Departamento: Genética animal; Genética molecular e de microrganismos; Genética quantitativa; Genética vegetal; Me
• País: BR
• Palavras-chave em Português: Macaúba - Melhoramento genético; Embriogênese somática; Famílias de polinização aberta
• Palavras-chave em Inglês: Macaúba - Genetic improvement; Somatic embryogenesis; Open-pollinated families
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA::MELHORAMENTO VEGETAL
• Link de acesso: http://locus.ufv.br/handle/123456789/1409

The establishment of an efficient protocol for obtainment and maintenance of pro- embryogenic masses able to produce somatic embryos is required for in vitro large scale propagation of A. aculeata. The significant effect of genotype on inducing somatic embryogenesis in vitro is essential to evaluate progenies of different arrays of open- pollinated A. aculeata. To this end, the aims of this work were to evaluate progeny arrays of open-pollinated A. aculeata by induction of somatic embryogenesis in vitro and optimize the process of somatic embryogenesis of this species from zygotic embryos. Mature zygotic embryos from 19 families of A. aculeata were inoculated in Y3 containing 9 μM of Picloram and/or Dicamba, both combined with 0.9 μM of 2iP. Families showed significantly different responses to the characters swolen embryos (SE), percentage of callused embryos (CALE), percentage of embryogenic callus (EMCA), and percentage of oxidation (OXID), in the induction phase of somatic embryogenesis. Through analysis of genetic diversity, the 19 families were separated in 5 groups in medium supplemented with Picloram, whereas in medium supplemented with Dicamba dissimilarity formed 4 groups. The medium supplemented with Picloram was more efficient on the characters SE, CALE, and EMCA, while medium supplemented with Dicamba was superior to the characters number of embryogenic lineages (ELINs) and OXID. Of the 19 families tested, 16 showed the ability to form ELINs, which are in multiplication medium with 18 μM of Picloram for more than 24 months without prejudice to their embryogenic competence. The ELINs showed granular appearance, yellow color and translucent appearance. The produced pro- embryogenic masses (PEMs) were more efficiently matured in medium with 5.5 μM of ANA combined with 2.5 μM of 2iP supplemented with activated charcoal, being characterized by elongation and changes in color from translucent yellow to opaque white. Although families behave distinctly in each germination medium, the family 9 had the highest number of germinated somatic embryos (GSE) in medium containing GA3. The process of germination of zygotic and somatic embryos is similar, occurring primarily elongation of the cotyledon petiole and the growth of haustoria. Histological analysis allowed us to verify the formation of somatic embryos with a closed vascular system and the presence of a peculiar mucilaginous layer in the protoderm formed, a characteristic that may serve as a marker for the process of embryogenesis of A. aculeata. This study is a pioneer in obtainment and maintenance of embryogenic lineages and in vitro response analysis of different families of A. aculeata.