Somatic embryos from Phalaenopsis classic Spotted Pink (Orchidaceae) protocorms

Embriões somáticos provenientes de protocormos de Phalaenopsis classic Spotted Pink (Orquidaceae)

ABSTRACT:

The aim of the present study was to induce the formation of somatic embryos in protocorms from Phalaenopsis Classic Spotted Pink hybrids at two physiological maturation stages, namely: 80 and 120 days after seed inoculation (DASI). Protocorms were inoculated in ½ MS medium supplemented with 0.1 mg L^-1 ANA and 3 mg L^-1 TDZ. Protocorms were inoculated 120 days after sowing were more developed at the 15^th cultivation day due to the formation of pro-embryogenic structures. It was possible seeing the formation of globular- and torpedo-stage somatic embryos at the 30^th day of cultivation in somatic embryogenesis (SE) induction medium. The protocorms inoculated at the 80^th DASI did not formed somatic embryos; they oxidized 20 days after cultivation in SE-induction medium. The formation of somatic embryos happened directly on the explant, thus characterizing a direct somatic embryogenesis. The embryos converted into plants when the somatic embryos were transferred to the nutrient medium containing no growth regulator. Therefore, it was concluded that the somatic embryos induction from protocorms 120 days after sowing was positive, since the embryos were able to become plants and presented vegetative organs with morphological traits similar to those of the matrix plant.

Key words:
orchid; protocormoids; somatic embryogenesis