The present work evaluated the development of embryogenic callus from transversal ovary sections. The experiments were carried out under two experimental regimes using combinations of IAA (0; 5.71; 8.56; 11.42; 14.27μM) and 2,4-D (0; 13.57; 18.10; 22.62μM) or combinations of 2,4-D with BA (0; 4.43; 6.65; 8.87; 11.09μM). Assessments were made of anatomical aspects of the callus and for the presence of embryogenic structures using cytochemical and histological analyses and stereomicroscopic and scanning electronic microscopic observations. Treatments with 2,4-D and IAA produced friable calluses demonstrating cellular acquisition of morphogenetic competence as well as the formation of pro-embryogenic sectors. The expression of embryogenic program could be observed, with proembryogenic cell clusters developing into globular embryos. These results offer the possibility of using new types of explants for culturing helicons that avoid the growth of endophytic bacteria.
Callogenesis; growth regulator; histology; scanning electron microscopy
