13 research outputs found
Organogenesis and embryogenesis in several hypericum perforatum genotypes
St John’s wort (Hypericum perforatum) is a valuable plant used as a herbal remedy or in phytopharmaceutical drugs to
treat a variety of physical ailments. Much research has been performed to study the biochemical production of secondary
metabolites of in vitro cultured plants or organs. However, all of these studies have looked at the regeneration of plants
from explants in only one genotype. In addition, no study has revealed the mechanism of plant regeneration in
H. perforatum, i.e. organogenesis or somatic embryogenesis. We found that different genotypes Helos, Topas, Elixir, and
Numi responded similarly to regeneration medium. The regeneration responses (i.e. callus, root, or shoot production) of
identical explants from different genotypes were similar. However, the source of explant material (leaves, hypocotyls, and
roots) from the same genotype had significant effects on the response to media and plant regeneration frequency. Using
scanning electron microscopy and light microscopy, the progress of organogenesis and embryogenesis under similar
culture conditions was recorded. Root segments were the most responsive explants, producing the maximum number of
shoots per explant of all the genotypes.Fundação para a Ciência e a Tecnologia (FCT) -
POCTI/AGR/40 283/2001, SFRH/BPD/17102/2004