الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This investigation was conducted in the Tissue Culture
Laboratory. Horticulture Department, Faculty of Agriculture,
Moshtohor during the period from 1995-1997 to study the
possibility to use tissue culture techniques to produce colonal
propagation for Magnolia and MulberrY plants. New growing
shoots were taken at the beginning of the growing season, washed
with running water, divided into small parts and immersed in an
antioxidant solution containing (150 mgIL. ascorbic acid and 100
mg/L. citric acid) for 20 minutes. The treated parts were sterilized
for 15 minutes using 100/0 Clorox (commercial bleach) plus two
drops of Tween-20, then transferred into sterilized water 3-times for
5 minutes each. Shoot-tips (0.5 nun thick) were excised from the
terminal parts, while the rest of these parts were divided into onenode
cuttings as explants under aseptic conditions. The prepared
explants were cultured on different media i.e., Murashige and
Skoog, Lepoivre and Woody plant media. The used basal medium
was supplemented with 0.1 mgIL. rnA (Indole 3-butric acid), 1.0
mgIL. BAP (6-benzyl amino purine), 30 gIL. sucrose and 7 gIL.
Difico Bacto agar for the establishment stage. However, during the
proliferation stage the same aforementioned supplementations were
added also to the used basal medium except BAP which varied
according to the treatment. In the rooting stage IBA was only
increased, but other constituents of the established medium were
used. Generally, pH of the used medium was adjusted to be 5.7, and
autoclaved at 121·C and 15 Iblin2 for 15 minutes. The cultured
explants were incubated under 16 hours of artificial light
(fluorescent light at 30 Mlm2/sec) and 8 hours of darkness at
temperature of 28 _ 30.C. SubcUlturing was done regularly at
4
weeks for all stages.
Anyhow, the obtained results can be summarized as follow:
I.. Establishmentstal&e:
I-Solid Murashige and Skoog medium was superior in all
measured parameters for explant establishment and development
for Mulberry plant, while, woody plant medium exerted an
adverse effect on explant development parameters of Magnolia
plants.
2- The highest explant development parameters occurred when the
explant was collected either during January to March or April to
June periods. However, the third period was the worst in explant
development and greening in Mulberry plants.
3- Magnolia explants collected during the second period during
July to September is the best for explant development, greening
and bud efficiency.
4- Antioxidant solution pretreatment succeeded in reducing the
accumulation of phenolic compounds as reflected in decreasing
necrosis of Magnolia plants. Moreover, the combination of
antioxidant solution as pretreatment and 300 mgIL. activated
charcoal to the cultured medium took the second rank in this
respect.
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5- The establishment peak was reached after 30 days from
culturing time for Magnolia plants.
II. proliferation stage.
1-Proliferation was enhanced when BAP was added to Murashige
and Skoog medium in relation to kinetin, zeatin and thidizuron.
2-The lower concentration of BAP (0.5 mgIL. and 1.0 mg/L.)
encouraged growth and chlorophyll and caused less necrosis.
However, using of 3 mg/L. BAP increased proliferation of
Mulberry plants.
III.. Roolin, stage.
III.A. Shoot elongation:-
1-Shoot elongation was increased when 2.0 mgIL. GA3 was used
instead of lower concentrations (0.5 and 1.0 mgIL.), where these
lower concentrations improved chlorophyll in Mulberry plants.
2- Indole 3-butyric acid was the most effective auxin in inducing
the best root formation for Mulberry plants.
III.B. Root formation: ..
1- Liquid medium of Murashige and Skoog medium on other
medium states in shoot development, greening and rooting.
2- Indole 3-butyric acid was the most effective auxin in inducing
the best root formation.
IV.. Acclimatization stage.
1-The combination treatment of33% sand + 33% peatmoss + 33%
loam induced the highest percentage of Mulberry plantlets
survivals.
2- Combination treatment (33% sand + 330/0 peatmoss + 330/0
loam) induced the highest percentages of Mulberry survival and
reached up to 93%.
3-Different growth parameters (plant length, number of shoots,
average shoot length, number of green leaves and growth index)
were slowly increased during the first three weeks. While, fast
increased was noticed during the latest three weeks of gradual
adaptation either laboratory, greenhouse or filed phases.