الفهرس 
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Abstract
SUMMARY
Many problems in the field of apricot husbandry are still without clear solve
such as its proper propagation . Tell now apricot is propagated mainly by seeds
under Egyptian conditions, very little is known about the seedling growth
behaviour. The present work was dealing with the response of apricot seedling under
the treatments of some growth regulators, mainly GA3 and IAA and the presence or
absence of some micro-nutrients in the germinated media, i.e. Zn, Mn and Fe .
Three experiments were conducted under sand culture technique as follows:
Experiment I :
Effect of GA] or IAA at 10 ppm on germination, fresh or dry weights, some
organic and nutrient content of the germinated cv. EI-Hamawy apricot seeds.
Experiment II :
Effect of soaking cv. EI-Amar apricot seeds in some growth regulators on
germination and seedling growth behaviour.
Experiment ill :
Effect of Zn, Mn and Fe deficiencies on germination, growth and some
chemical composition of apricot cv, EI-Amar seedlings.
The following results were obtained :
A) Experiment I :
1) GA3 at 10 ppm enhanced the germination percentage of apricot seeds cv.
EI-Hamawy.
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2) This stimulatory effect of GA3 on germination percentage was related
partially to its acceleration effect 011 water absorption rate.
3) As a general, during the development of radical stage, great decline in dry
weight was observed. Such reduction was less by using GA.3with comparing to IAA
or control treated seedlings .
4) Both GA3 and IAA at the rate of 10 ppm changed the accumulation of
carbohydrate fractions, as both were greatly reduced the total amount of
carbohydrate during radical developing stage and enhanced their accumulation
during plumule emergency stage. The reduction or stimulation effects were more
pronounced with IAA as compared to the corresponding ones of GA
3
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5) The dominant and abundant protem fraction in EI-Hamawy seeds and
seedlings, as a general, is the hard non-soluble protein followed by water, salt,
alkaline buffer-soluble proteins, while alcohol fraction is the lowest in this respect
6) GA3 or IAA at the rate of 10 ppm stimulated the relatively high
accumulation of water and alkaline-soluble proteins, while other fractions seemed
to be less than corresponding ones of control .
7) Glutamine is the more dominant bound amld mostly followed by leucine
& isoleucine, aspartic, valine, arginine, phenylalanine, histidine and the lowest one
is proline . Free amino acids are mostly found in trace amounts during different
germination stages. In addition, arginine and histidine \ ere not detected in free
amino acids in the seeds, while both are present in bound amino acids .
8) The increase in the germination and eedling emergency rates by GA
J
were
associated by the decline in total amino acids during radical developing stage and
relatively higher ones during plumule emergency stage as comparing to
cOl’responding ones of control. The stimulatory effect of GAl on germination
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percentage was associated by stimulatory effect on total bound amino acids speciaUy
glutamine, alanine and valine. The great variations in the individual amino acid
eitber free or bound ones seemed to be involved with tbe process leading to seedling
emergency.
9) As a general, most nntrients, either on concentration or total amounts per
seedling increased during the germination stages as related to the initial stored
amounts in the embryo .
10) The higher gennination rate of GA3-treatedEI-Hamawy apricot seeds over
the control was associated wilb tbe bigher absorption rate of N, K and Mg over the
control or IAA treated ones.
B) Experiment II :
11) GA3 at 10 ppm or GA3 + IAA at 5+5 ppm enhanced the germination
percentage of EI-Amar apricot. Other treatments with MIl or CCC seemed to
minimized the total gennination percentage .
12) Treatments with GA3, IAA, MH or CCC regulated the seedling growth
rate in the terms of root length, lateral roots number, stem length, number of leaves
and fresh and dry weight .
13) AUtreatments with growth regulators exhibited their regulatory effect on
seedling growth behaviour of ”EI-Amar” apricot through their effects on the changes
in many metabolic products, such as carbohydrate, protein, total amino acids
fraction and nutrients uptake .
14) The dOminant protein fractions were differed in EI-Amar seedlings after
72 days from soaking with different tested seedling organs, indicating that e ery
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seedling organs having its specific protein fractions. The treatments with growth
regulators greatly affected the protein fractions in different El-Amar seedling
organs, and that may reOected their changes effects on seedling growth behaviour
15) Many nutrients must be present in the growing medium of EI-Amar
apricot from the beginning of germination as the stored reserved amounts in stored
seed organ, cotyledons, seemed to be not sufficient COl’ maintaining the growth of the
developing seedlings. The regulatory effects of the tested substances was associated
with the control of nutrients uptake . The balance between different nutrients
seemed to have a part in the regulatol”y effect of the used growth substances on
growth behaviour of the treated seedlings.
C) Experiment III :
16) The present or absence of Zn, Mn or Fe seemed to have slight effects on
gelmination percentage and the seedling rate index .
17) Presence or absence of any tested micro-nutrient affected seedling growth
especially during latter periods of growth, as the reserved amounts of these nutrients
in cotyledons were not sufficient to supply the developing seedlings with their
requirements .
18) The absence of Zn, Mn or Fe minimized the concentration of
photosynthetic pigments, and that affected the growth behaviour of seedling.
19) Omission of micro-nutrients exhibited their effects on plant growth
through the trouhls in carbohydrate, protein and amino acid metabolism as well as
the unbalance between the uptake and accumulation of different nutrients.
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