Narcissus and Daffodil

230 C. Codina
Accumulation of alkaloids in the liquid medium
Although the release of alkaloids into the medium increased until the fourth week
of culture, from then on, and coinciding with the necrosis and vitrification of the
tissues, excretion decreased drastically (Figure 7.11). As in the bulblets, the main
alkaloids released to the medium were galanthamine and haemanthamine, reaching
values of 404.2 and 295.5 µg/g FW, respectively. In general, the levels of alkaloids
released by the shoot-clumps into the liquid medium were higher than those
released by the bulblets.
Accumulation of alkaloids in tissue
In the control shoot-clumps, or in those treated with low doses of paclobutrazol,
the alkaloids were accumulated mainly in the tissue, whereas at concentrations of
5 mg/l or more of this growth regulator the alkaloids were mainly released to the
culture medium (Figure 7.12). This fact could be related to the degree of vitrification,
which was proportional to the concentration of paclobutrazol.
mg/g DW
mg/g DW
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0.80
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
N-formylnorgalanthamine
0 1 3 5 10
Paclobutrazol (mg/l)
Haemanthamine
0 1 3 5 10
Paclobutrazol (mg/l)
ts
cm
ts
cm
mg/g DW
mg/g DW
0.70
0.60
0.50
0.40
0.30
0.20
0.10
0.00
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00
Galanthamine
0 1 3 5 10
Paclobutrazol (mg/l)
Tazettine
0 1 3 5 10
Paclobutrazol (mg/l)
Figure 7.12 Accumulation of alkaloids in both tissue (shoot-clumps) and liquid medium at
the end of the experiment with paclobutrazol (bars represent the SD calculated
from three replicates). ts, alkaloids detected in the tissue; cm, alkaloids released
to the culture medium.
ts
cm
ts
cm