The development of an efficient regeneration system is crucial for the genetic transformation of sugarcane. The aims of this study were to regenerate plants from somatic embryos and analyze the origin and division pattern of cells during the different embryonic developmental stages of the sugarcane cultivars RB855156 and RB72454. For both cultivars, the best results for embryogenic callus induction were obtained with explant cultures on culture medium containing 13.5 µM 2,4-dichlorophenoxyacetic acid (2,4-D) followed by callus culture on solid medium with 4.5 µM 2,4-D. A higher rate of shoot induction was observed in RB855156 with the addition of 8.9 and 17.8 µM benzylaminopurine (BAP); this higher rate was also observed in RB72454 with the addition of 17.8 µM BAP. Murashige and Skoog (1962) (MS) medium containing 2.5 and 5.0 µM indolebutyric acid (IBA) for RB855156 and RB72454, respectively, was suitable for rooting. The plantlets were successfully acclimatized and the plant survival rate was 100% for both cultivars. Histological analysis revealed that the shoots in both cultivars originated from somatic embryogenesis.
tissue culture; somatic embryos; anatomy; 2,4-D; Poaceae
