Biotechnology tolls in Araucaria angustifolia conservation and improvement: inductive factors affecting somatic embryogenesis
Vanildo Silveira, Neusa Steiner, André Luis Wendt dos Santos, Rubens Onofre Nodari and Miguel Pedro Guerra
Biotechnological techniques based on somatic embryogenesis have been employed for capturing genetic gains in forest breeding programs. The present work aimed at studying the factors associated with the induction of somatic embryogenesis in Araucaria angustifolia. Zygotic embryos in different developmental stages were inoculated in a LP medium supplemented with 2,4-D, BA and KIN. Embryogenic cultures were inoculated in a LP liquid medium free of plant growth regulators. ABA and/or PEG 4000 were evaluated for the development of somatic embryos. The embryogenic induction was dependent on the genotype of the mother plant, ranging from 21.9% to 55.2%. Suspension cultures showed a 5.6 times increment of the initial cell volume after 33 days in the culture medium free of plant growth regulators. It was possible to establish and multiply autonomous embryogenic cultures. The medium containing ABA (50 mM) and PEG (1%) resulted in the development of globular and torpedo somatic embryos.