Liquid Culture Systems for in vitro Plant Propagation

370 Barbara Ruffoni et al.
No.shoots/biomass unit
8
7
6
5
4
3
2
1
0
a
b
BA 0 BA
2.22
a
BA
4.44
b
a
Anc 0 Anc 3.9 Clone
RE
a
a
Clone
PAN
Figure 4: Ixia, cv. RE and PAN, efficiency of shoot differentiation related to the BA
concentration and ANC presence in the media (different letters indicate significant differences
at p=0.05, SNK test).
The histological analysis confirmed the development of adventitious
shoots with a regular formation of vascular connections from the calli
previously grown in the absence of ANC. In figure 5a a clear meristematic
activity can be observed at the callus surface: also a leaf-shape single
structure with an initial development of vascular connections within the
callus cells can be observed in figure 5b. The induction of embryo-like
structures clearly separated from the callus cells was evident in the calli
grown in the presence of ANC (Figure 5c,d).
In figure 6a calli with shoot organogenesis can be observed, and a single
structure can be seen at a higher magnification (Figure 6b, 120x). The best
quality propagules obtained in the study are shown in figure 6c. These
present a bipolar structure with a green aerial part and well-connected small
roots. This production of singularised propagules in the medium, shows a
characteristic belonging to the somatic embryogenesis pathway. In few cases
abnormal structures were observed.
When plants were transferred to the greenhouse, they grew for about 30
days: then the leaves senesced and the corm diameter increased up to 1 cm.
The corms then became dormant.