الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
SUMMARY
- The present investigation was carried out in an
attempt to give
some information about the growth of
Azolla caroliniana under di”fferent levels of some
growth regulators such as GA3’ IAA, MH and B-9.
To approach this aim, two laboratory experiments
were carried out under semi-controlled conditions which
include
1- Response of Azolla caroliniana plants to GA3
and IAA.
2- The interaction effect of GA3. IAA. MH,B-9 and
’theil”i”nteraction on Azolla carol iniene plant.
This investigation was carried out in nutrition
lab., Institut. Oceano. Fisher. Reserch. NIOF. Egypt.
during 1986.1987 including two experiments
Experiment I
_ IAA :Applied at rates 5.10.20.30.40 and 50 p.p.m.
_ GA3 :Applied at rates 10.20.40.60.80 and 100 p.p.m.
Experiment II :
IAA :Applied at rates 1.2 and 5 p.p.m.
_ GA3 :Applied at rates 0.1.0.5 and 1 p.p.m.
B-9 :Applied at rates 20.40 and 100 p.p.m.
_ MH :Applied at rates 1.10 and 30 p.p.ro.
And their interactions.
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The following data were recorded.
a) Fresh weight/vessel.
b) Numberof fresh fronds/gram.
c) The numberof fronds/vessel.
cl.>:·Fresh weight/frond.
- .
e) Dry weight/vessel.
f) Dry weight/frond.
g) Growth percentage compared with starting sample.
h) Determination of Macro-nutrients content. i.e. N,P,
K and Micro-nutrients, i.e. Mn. Zn. Cu.~
The results obtaind could be summarized as’
follows :-
A) Experiment I :
a) Growth behaviour
1) Both tested growth promoters. GA3 and IAA,
seemed to minimized the development of Azolla fresh
weight and dry as compared with the un.t.r-e ated control
plants. and GA3 seemed to have a saperior effect than
IAA in this respect.
b) Chemical composition
1) The untrea.ted plants possessed the highest
nitrogen concentration as compared with other treatments
as well as starting sample. The various levels of GA3
depressed greatly the nitrogen concentration while the
levels of IAl stimulated it:
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2) The levels of GAs seemed to depress the atmospheric
nitrogen fixation.
The treatmentsof IAA seemed to have lower depressive
effect on the nitrogen fixation activity than GA3
treatments. .•• >
3) Both GAs and IAA levels affected the· accumu la-r ’
tion of phosphorus in Azolla plants. Both GA3 and IAA
reduced the concentration and total phosphorus amounts
in Azolia plants;
IAA treated plants possessed higher concentration
of phosphorus than the starting sample.
4) The treatments of GAs or IAA declined the absorption
ofpotassium by Azolla plants.
GA3 levels showed higher depressive effect than
IAA in this respect.
5) The Azol1 d plants possessed high amounts of Mn
followed by Zn while eu was the lowest. The total
amounts of these micro-elements showed a continous
decrease with the application of GA3. while no clear
trend was obseved in the case of IAA except a decrease
in total amounts of the three nutrients. -
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B) Experiment II :
a) Growth behaviour
1) The presence of the tested growth regulators.
in nutrient media of Azolla plant reduced the production
of fesh weight biomass per vessel except Kylar as
such,anti-GA ~”which stimulated ”the production of fresh·
weight per vessel over the control. All treated plants
produced higher fresh weight than the starting sample.
2) The increase of GA3 levels decreased gradually
the fresh weight biomass under fixed Kylar level.
However. IAA stimulated greatly the depressive effect
of GA3 on fresh weight biomass.
3) Kylar seemed to minimize the depressive effect
of 11\1\ at the moderate and high level. MH antagonist
the depressive effect of IAA at the lowest level.
4) The GA3 single and IAA levels have a relatively
retarding effect on dry weight production of Azolla
bIomass per vesse I. Kylar treatments adverse the depressive
effect of GA3 on dry weight biomass. The using of
MH seemed to have more or less than an adverse action
on the depressive effect of GA3 on dry weight per ves- ~
sel, while IAA stimulated the depressive effect of GA3
on dry weight per vessel. Kylar adversed the inhibitory
effect of IAA as it was showed by GA3-Kylar interaction.
MH seemed to adverse the inhibitory effect of
IAA.
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5) ·Generally all the tested growth SUbstances. increased
the fragmentation of AzalIa biomass over the
control treatments.
b) Chemical composition :
1)”The different treatments with single growth
substances seemed to have higher nitrogen concentration
compared with starting sample while most treated plants
possessed less nitrogen concentration than the control.
Kylar seemed to a stimulatory effect on nitrogen fixation.
2) Kylar application seemed to regulate and
diverse the retarding effect of GAa on nitrogen fixation.
MH treatment diversed the inhibitory effect of
GAa on nitrogen fixation. Kylar diversed the depressive
effect of IAA on N fixation.
3) The growth substances affected the accumulation
and absorption of phospgorus by AzolJa plants.
4) GAa and IAA have a retarding effect on phosphorus
absorption. Kylar seemed to have a stimulatory
effect on the absorption rate of phosphorus. this
stimulation was extended as reversable action over the
depressive effect of either IAA or GA3.
5) GAa• lAA and MH seemed to retard the accumulation
of K while. Kylar stimulated ,uch accumulation.
PotasDum absorption rate trend seemed to be the same of
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phosphorus and nitrogen. IAA and GA3 retarded the absorption
rate of potasium while Kylar and MH stimulated
such absorption.
6) The absorption of Manganese was continuous under
the different treatments as compared with starting
sample. ~~
7) kylar decreased the concentration of Zinc. GA3
stimulated Zinc concentration but such increment
decreased gradually with increasing GA3 level. With
regard to the effect of MH on the effect of GA3 or IAA.
most of the used rates declined Zinc concentration in
Azolla plant tissues.
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