الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The white squill (Urginea maritima (L.) Baker) is an important medicinal and ornamental bulbous crop belong to family Liliaceae. Hot
water treatment (HWT) was significantally affected when explant exposed
to 50 ˚C for one hour. All explants survived and regeneration increased
from 60% close to 100%. Bulblets generated during initiation were cut into
halves and used as secondary explants. The auxin transport inhibitors 2,3,5-
triiodobenzoic acid (TIBA) and naphthylphthalamic acid (NPA), and the
anti auxin p-chlorophenoxyisobutyric acid (PCIB) at different
concentrations significantly (P<0.05) increased regeneration (the total
number of new shoots and meristems). The outgrowth of meristems into
shoots was inhibited with increasing concentration. Histological
observations showed that the increase of the number of shoots and
meristems corresponded to an increase in the number of vascular bundles
originated from provascular bands near preexisting axillary meristematic
cells.
Fluridone, applied during in vitro culture, strongly stimulated
adventitious shoots and small bulblets formation of Urginea maritima scale
explants. The explants were cultured on Murashige and Skoog (MS)
medium with different concentrations of fluridone and 10μM BA and
0.5μM NAA. At middle fluridone concentrations (٣μM), the scales gave
the highest adventitious shoots number (4.58). The whole explants with the
new plantlets were transferred to MS medium supplemented with different
concentrations of sucrose (3, 6 and 9%) and supplemented with 10 μM BA
and 0.5 μM NAA under the normal condition. At 6% sucrose it was shown
that the highest numbers of new bulblets were formed (5.40) with the
highest fresh weight (0.94 gm) with the previous treatment of 3μM
fluridone.
In vitro multiple shoots of Urginea maritima L. were induced. Twin
scales were cultured on MS medium containing different concentration of
TDZ; however 10 μM TDZ proved to be optimal for the production of
maximum number of shoots. Bulblets formation was markedly promoted
by the interaction between paclobutrazol and sucrose at different levels
tested. Paclobutrazol in highest rate (1 and 3 μM) combined with 9% and
12% sucrose respectively was achieved the highest fresh weight (0.92) of
the regenerated bulbs. Acclimatization was investigated for the resulted
bulb using different treatments to break the dormancy of the bulbs
comparing to the control. Dry heating treatment for the bulbs for 2 weeks
was enough to raise the dormancy-breaking until 70%. Also, Proscillaridin
A (PsA) was examined in the regenerated bulbs using HPLC. The
concentration of PsA was found to be the highest (1.62mg/gm) with 10μM
paclobutrazol and 12% sucrose.
Callas (Zantedeschia spp.) belonging to Araceae family are
ornamental plants with high commercial demand as plants in pot and cut
flower. A method for the multiplication of Zantedeschia Odessa is
presented using shoot tip proliferation onto MS medium supplemented with
different concentrations and combinations of imazalil (IMA) and fluridone.
Imazalil concentrations (0, 4.5, 13.5 and 45 μ M) were used in combination
with 0.5 μM BAP. The new shoots were transferred after 8 weeks to
standard MS media which is supplemented with 0.5 μM BAP. The data
indicated that supplementation with 45 μM imazalil induced the highest
number of shoots (7.80) and shoot length (6.30cm), when compared to the
other concentrations. Also, different treatment of fluridone were applied
with the Zantedeschia shoots in combination with 13.5μM imazalil for 8
weeks then were subcultured on standard medium for 8 weeks. The highest
concentration of fluridone was the best one giving the highest shoot
number (10.48) and shoot length (5.8 cm).