الفهرس 
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Abstract
This study was conducted to use the tissue culture techniques to propagate ornamental
Ipomoea batatas plants via estimating the appropriate concentrations of applied plant growth
regulators to achieve the best micropropagation. The used plant materials were nodal segments
explants were conducted at the Plant Tissue Culture Laboratory of the Plant Production
Department, the Faculty of Agriculture Saba-Basha, Alexandria University, during the period
from 2018 to 2019.
This study to find out the appropriate micropropagation protocols for abovementioned species using nodal cutting technique. Respecting the initiation stage (starting stage)
nodal segments were cultured on MS medium (1962) fortified with (BA) at three concentrations:
0.0 (nil), 0.50 and 1.0 mg/l, in combinations with auxin Naphtaleneacetic acid (NAA) at four
concentrations: 0.0 (nil), 0.5, 1.0 and 1.5 mg/l. As for multiplication stage, the neoformed
propagule of the initiation stage was sectioned into single leaflets nodes. The excised nodal
cuttings were subcultured onto the multiplication media (i.e. MS-basal-medium) which
supplemented with BA at four concentrations: 0.0 (nil), 0.5, 1.0 and 2.0 mg/l, in combinations
with NAA at three concentrations: 0.000 (nil), 0.125 and 0.250 mg/l. The obtained shoots of
Ipomoea batatas from the multiplication stages were, individually separated or excised and
subcultured on MS medium (1962) augmented with two types of auxins, IBA at four
concentrations: 0.000 (nil), 0.125, 0.250 and 0.375 mg/l, in combinations with NAA at three
concentrations: 0.000 (nil), 0.125 and 0.250 mg/l, the produced plantlets were established ex vitro
and in vivo (as concluded from the obtained results). However, the means of the following
characters were determined after 35 days of growth, for Ipomoea batatas: number of neoformed
shoots, shoot length (cm), number of nodes & leaflets and roots per propagule.
However, the main obtained results of this study can be summarized as follows:
5.1 Influence of different concentrations of sodium hypochlorite and mercuric chloride on
surface sterilization efficacy
The obtained results indicating that using chlorox (commercial bleach) at 40% (v/v)
achieved the highest percent survival (90%) compared to the other treatments which reflected on
contamination percent (%). In this respect, using 1.00 mg/l of mercuric chloride, led to the
highest percentage of survival of uncontaminated explants, i.e. 80% and 20% for contamination
percent. The combination between sterilants, chlorex and mercuric chloride at 40% and 1.00
mg/l, orderly brought about was the highest percent of survival (100%).
5.2 Micropropagation
5.2.1 Initiation stage
The highest mean values for the studied characters were always recorded at the
precense of NAA from the culture medium (1.00 mg/l). On the other hand, the main effect of BA
tested levels on the above-mentioned traits, commonly, as BA levels increased the given
characters decreased. Concerns the interaction between NAA at 0.1 mg/l and BA at nil level, led
to the highest mean values of the studied characters