The embryos culture in vitro allows studies in the physiology breeding areas, facilitating the rescue of immature embryos, originated from incompatible crossings. In apple, the immature embryos generally present dormancy and lower germination. The objective of this work was to test concentrations of BAP in different immersion periods for break of the dormancy and germination of apple immature embryos. The embryos were extracted from fruits seeds originated from the crossing between apple rootstock Marubakaido and M.9, accomplished in adult plants in Epagri - São Joaquim (SC). The 50 collected fruits were submitted to a sterilization with alcohol 96º for 10 minutes and after with NaClO solution (2%) for 20 minutes. The removed seeds were submitted to a disinfestations treatment with alcohol 70% for 30 seconds and with NaClO solution (1,25%) for 15 minutes, followed by three washes with sterilized water and autoclaved. The embryos were inoculated in 10 ml of MS/2 culture medium, to which was added 100 mg.L-1 of myo-inositol, 30 g.L-1 of sucrose and with BAP (0, 6 and 12 mg.L-1) and 6 g.L-1 of agar and with pH adjusted to 5.8. The embryos were maintained by 24 or 48 hours in this medium and later transferred for a medium MS/2 without growth regulators. There was no contamination or oxidation. The concentration that promoted larger growth of the embryos was of 6 mg.L-1. However, the best general aspect in the coloration intensity and formation of sprouts was obtained when medium containing 12 mg.L-1 was utilized.
dormancy removal; in vitro; Malus prunifolia; Malus pumilla; BAP
