Figure
3. Somatic embryogenesis in petiole cultures of Pelargonium x
domesticum cv. Madame Layal.
(a)
Formation of globular stage somatic embryos on media supplemented with
different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) and
6-benzylaminopurine (BAP) after primary culture as shown in Figure 4.
(b–d)
Histology of the development of somatic embryos.
(b)
Longitudinal section of globular stage somatic embryos formed on medium
with 10 µmol l-1 2,4-D and 2 µmol l-1 BAP after
10 days in culture. The structure of the embryos is characterized by
small cells with dense cytoplasm.
(c–d) Longitudinal
sections of more developed somatic embryos from cultures grown on medium
supplemented with 4.5 µmol l-1 2,4-D and 2 µmol l-1
BAP followed by a transfer to growth regulator free medium after 8 days.
Note the well-organized shoot and root meristems visible as highly stained
areas.
(c)
Heart-torpedo stage embryo.
(d)
Cotyledonary stage embryo.
Bar:
1 mm (a);
0.05 mm
(b,c); 0.1 mm
(d). |