الفهرس 
RegenerationOnly 14 pages are availabe for public view
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Abstract
Saccharum officinarum is one of the world’s most important crops
and produces a sugar that is valuable all over the world besides it is used
in also as paper manufacturing and foot industry. Sugarcane, is
constrained severely can summarized based on several reports: (1)
sugarcane normally propagates by its bud, with a low proliferation rate
and the reproducing part (the bud) is also the economically used part of
the sugarcane plant, which restricts the availability of sugarcane seeds
needed for cultivation, (2) Easily infected by soil- borne pathogens such
as bacterial ratoon stanting disease and virus diseases. Mosaic and streak
disease, which cause heavy losses in yield, (3) Normal breeding of
sugarcane is a real problem due to poor flowering and seed set. Indeed,
most crop improvement programs for this species were confined to
evaluation and selection of naturally occurring clonal variants. therefore,
the aim of this study was to apply different techniques of plant
biotechnology and biochemistry i.e. tissue culture, in vitro propagation,
molecular markers, analysis of (chlorophylls, phenols, Indols,
carbohydrates and flavonoids) as biochemical methods can also help in
sugarcane breeding.
The initial approach for in vitro propagation protocol of S.
officinarum was based on apical meristem (explants). Numerous
experiments were carried out to provide an effective, reliable and
reproducible protocol for in vitro propagation of sugarcane. The MS
medium containing 2mg/l Kin +0.25 mg/l NAA showed the highest
multiplication rate, with value around seven shoots per explant and gave
the maximum number of leaves and nods while longest shootlet (18.7 cm)
was recorded with 0.25 mg/l NAA for G.2003/49 cultivar. A positive
relationship was found between BAp+ NAA combinations and rate of
shootlets multiplication. MS medium having 1mg/l BAp in combination
with 0.25 mg/l NAA showed a high rate of shootlets multiplication (4.9) ,
maximum number of leaves and nods, However the longest shootlet (16.9 cm) was observed on 2mg/l Kin +0.25 mg/l NAA for G.T.54-C9 cultivar.
A well- developed elongated shootlets about (4-5 cm in length )were
excised from shoot clump and cultured on½ MS medium supplemented
with 2mg/l IAA+ 1mg/l NAA in favor of root elongation (2.03 cm). MS
half salts strength medium supplemented with 1mg/l NAA alone
enhanced the rate of root development (7.66) of sugarcane G.2003/49
cultivar. The maximum number of roots formed per shoot (3.3) was
recorded on ½ MS medium supplemented with 1mg/l IBA +1mg/l NAA.
Half strength MS medium supplemented with 1mg/l IAA+0.5 mg/l NAA
(4.60 cm) produced best results in term of longest root /shoot on
sugarcane G.T.54-C9. The in vitro derived plants were better
acclimatized under ex vitro condition when transferred on specially made
plastic trays containing peat moss + sand+ perlite (1:1:1) at periodical
intervals of taking special care not to damage the roots. About 80-90% of
the regenerated plantlets could tolerate and survive under ex vitro
environment or greenhouse conditions for the two sugarcane cultivars
(G.2003/49 –G.T.54-C9) respectively.
The molecular characterization of S. officinarum by ISSR- PCR at
the DNA level showed 6 subcultures of tissue cultures compered to
original materials. While, ISSR technique can be successfully applied to
determine the genetic fidelity of sugarcane plants. Amplification products
were separated by agarose- gel electrophoresis to reveal band
polymorphism. Out of 3 specific primers screened. The most informative
oligonucleotides bands for both two sugarcane cultivars were detected.
Three primers didn’t detect any somaclonal variations and showed 100%
monomorphic bands.
Quantitative determination of chlorophyll, total carbohydrate,
non-soluble carbohydrate, total Indols, total phenols and total flavonoids
using spectrophotometer were detected in leaves of the two sugarcane
cultivars (GT.54-C9 - G.2003/49) through different stages (open field,
tissue culture plantlets and acclimatized plants). The amounts of chlorophyll, total carbohydrate, non-soluble carbohydrate, total indols,
total phenols and total flavonoids in plantlets were higher than those in
acclimated plants and mother plants, respectively.
In this study, it was concluded that micropropagation is an
effective method for sugarcane culturing; This requires hundred plantlets
from single apical meristem with qualitative and quantitative traits like
mother plant and more stability through molecular analysis between
different subcultures.