الفهرس 
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Abstract
This study demonstrates the response of the eggs to the
effect of eight compounds related to 8 different growth
regulators groups (i.e. hexaflumuron, flufenoxuron, lufenuron,
diflubenzuron. Chlofluazuron, fenoxycarb pyriproxyfen and
tebufenozide ).
The laboratory of 8 regulators (3 JHA and 5 IGI) were
tested against the eggs of three important economic insects (0.
nubilalis, A. ipsilon and S. littoralis).
The direct effect of these compounds on eggs was studied
as results on hatchability and relative susceptibility of different
ages of eggs (i.e. one, two and three days old eggs) of O.
nubilalis, A. ipsilon and S. littoralis. On the other hand, the
indirect effects were, also, studied as latent effect of these
compounds on the subsequent stages of the previous insects
resulted from treated eggs.
Part I.-Effect of some insect growth regulators (IGRs) on the
hatchability of different ages of eggs:
1- Ostrinia nubilalis :
Data in these investigations revealed that on one day old
eggs, lufenuron increased percentage mortality of the tested
eggs than the other tested compounds. Flufenoxuron was the
second in its effect followed by pyriproxyfen, while
tebufenozide was the least effective. Lufenuron at (8000 ppm) on
one day old eggs, completely, blocked the embryonic
development and all the treated eggs failed to hatch, while it
Summary -155-
gave the highest mortality (58.13 and 50.23%) after treating the
two and three days old eggs, respectively.
2-.Agrotis
Hexaflumuron increased percentage mortality than the
other tested compounds on one day old eggs. In the same time
lufenuron occupied the second rank, followed by flufenoxuron,
while the last degree of efficiency caused by pyriproxyfen.
Hexaflumuron (8000 ppm) on one day old egg,
completely, blocked the embryonic development and all the
treated eggs failed to hatch, while it produced the highest
mortality (96.1 land 90.82%) after two and three days old eggs,
respectively.
3-.Spodoptera littoralis:
Flufenoxuron was more effective on all ages of eggs (i.e.
one, two and three days old), while lufenuron occupied the
second order followed by pyriproxyfen. On the other hand, the
least degree of efficiency caused in the case of tebufenozide. The
highest concentration offlufenoxuron (8000 ppm) gave the
highest mortality (97.85,96.02 and 93.15%) on one, two and
three days old eggs, respectively. On the other hand, the effect of
tebufenozide was lower than other compounds, rates of mortality
were (41.2, 38.84 and 37.27%) at concentration of(8000 ppm)
on the same previously ages of egg.
In general, an increase of LC 50 values of all tested
compounds on O.nubilalis, A. ipsilon and S. littoralis led to
increase the eggs mortality percentages when the different ages
of eggs dipped in different concentrations of these compounds.
Summary -156-
Also, the freshly deposited eggs of the previous insects
were most sensitive than the other ages of eggs and the
sensitivity decreased in older eggs when treatment with different
concentrations of lufenuron, flufenoxuron, pyriproxyfen and
tebufenozide, while older eggs of O. nubilalis and S. littoralis
(i.e. two and three days old eggs) were most sensitive for
hexaflumuron and the sensitivity decreased in the freshly
deposited eggs.
Part Lli Relative susceptibility of different egg ages of O.
nublalis, A. ipsilon and S. littoralis.
Five compounds were used directly against one, two and
three days old eggs, (i.e. flufenoxuron, lufenuron, hexaflumuron,
pyriproxyfen and tebufenozide).
The LC 50 values, representing the ovicidal effect against
O. nubilalis, A. ipsilon and S. littoralis on one and two day old
eggs revealed the following:
l-Ostrinia nubilalis eggs:
Pyriproxyfen was more potent as an ovicide than the other
compounds on both developmental ages (one and two day old
eggs) where the LC50 values were (423.2 and 562.7ppm). On the
other hand, hexaflumuron was more toxic on the three days old
eggs than the others where LC 50 value was (812,3 PPm).
Concerning, the potency levels of the five tested
compounds at LC 50 levels, pyriproxyfen toxicity exceed with
7.94 folds than hexaflumuron, (3.69, 2.58 and 1.39) folds than
flufenoxuron, lufenuron and tebufenozide, respectively for one
day old eggs. While on two days old eggs pyriproxyfen toxicity
Summary -157-
exceed with 8.5 folds than lufenuron, 3.42, 2.83 and 1.07 folds
than flufenoxuron, hexaflumuron and tebufenozide, respectively.
2.Agrotis ipsilon eggs:
Flufenoxuron was highly toxic as an ovicide than other
tested compounds on all development ages, the LC 50 values were
(30.1, 52.2 and 60.4 ppm) for one, two and three days old eggs,
respectively .On the other hand, tebufenozide showed lower
effect where LC50 values were (2115, 4947 and 5695 ppm) on
the same previously ages of egg, respectively.
According to the toxicity index, flufenoxuron was the
most potent (toxicity index, 100 at the three LC 50 levels, (i.e.
one, two and three days old eggs).
In regard to relative potency levels, flufenoxuron toxicity
exceeded 70.42 folds than tebufenozide, (4.09, 2.39 and 1.18)
folds than hexaflumuron, pyriproxyfen and lufenuron,
respectively for one day old eggs. The same trend was obtained
on two and three days old eggs.
The tested compounds could be arranged according to
ovicidal activity on one day old eggs as follows:
Flufenoxuron, hexaflumuron, pyriproxyfen, lufenuron and
tebufenozide, where the LC50 values were (30.1,518.1,884.1,
1790.0 and 2115 ppm), respectively.
3.Spodoptera littorals eggs:
Tested compounds could be arranged according to LC 50 in
the following ascending order for one day old eggs,
pyriproxyfen, lufenuron, hexaflumuron, flufenoxuron and
tebufenozide.
Summary -158-
The toxicity index, for tebufenozide, flufenoxuron,
hexaflumuron and lufenuron were (2.14, 2.52), (12.79,14.2),
(15.21,26.36) and (32.46,31.03) as pyriproxyfen for one and
two days old eggs, respectively, at LC50 level. On the other hand,
for three days old eggs, tebufenozide, flufenoxuron pyriproxyfen
and lufenuron were (7.06, 35.45, 57.78 and 66.3) as toxic as
hexaflumuron.
The relative potency levels of the tested compounds at
LC50 level compound, PYriproxyfen, flufenoxuron, hexaflumuron
and lufenuron toxicity against one, two and three days old eggs
exceeded (46.72,39.68,8.18), (5.98, 5.63, 5.02), (7.11, 10.46,
14.16) and (15.17, 12.31,3.39) folds than tebufenozide for each,
respectively.
In general, the effectiveness of tested compounds varied
according to the stage of development of the egg.Also, the
younger eggs were generally more susceptible to the tested
compounds than older ones except with hexaflumuron.
ParLllLLatent effect ofIGRs on different ages of eggs of
o .nubilalis, A. ipsilon and S. littoralis.
Biological aspects of different stages resulted from treated
eggs. The result could be summarized as follows:-
l-Ostrinia nubilalis:
Flufenoxuron produced the highest larval mortality
percentages (87.5 and 80.0%) for larvae resulted from treated
one and two day old eggs, respectively. While, hexaflumuron
gave (72.5%) as highest larval mortality percentage for larvae
resulted from treatment of three days old eggs.
Summary -159-
For, pupation percentages, flufenoxuron revealed the least
percentages of pupation 60.0, 62.5 and 80.0% recorded after
treatment of one, two and three days old eggs, respectively.
Meanwhile, for malformed pupae, the application with
LC50 values offlufenoxuron, pyriproxyfen, and hexaflumuron
were (40.0, 38.59 and 21.54%, respectively compared with
2.78% for untreated eggs.
Hexaflumuron and flufenoxuron produced (16.36,
35.0%), (11.12, 25.0%) and (4.54, 18.18%) malformed adults
recorded after treatment of one, two and three days old eggs,
respectively.
For pupal mortality, hexaflumuron, pyriproxyfen and
flufenoxuron gave (28.67, 21.44 and 21.0), (25.17, 19.22 and
13.5) and (18.18, 16.16 and 7.76%) pupal mortality after
treatment of one, two and three days old eggs, respectively.
Z-Agrotis ipsilon :-
Larval mortality percentages were (83.33, 56.67,46.67
and 43.33%) and (60.0,41.67,20.0 and 11.67%) recorded after
treatment two and three days old eggs by LC 50 values of
1ufenuron, flufenoxuron, hexaflumuron and pyriproxyfen,
respectively.
While, for pupation percentages, the application with
hexaflumuron, lufenuron pyriproxyfen and flufenoxuron gave
(96.87, 80.0, 66.28 and 61.54%) and (97.89, 83.34, 81.99 and
77.14%) recorded after treatment of two and three days old eggs,
respectively.
Summary -160-
For deformed pupae, flufenoxuron gave (38.39 and
22.76%) as highest percentages of deformed pupae recorded
after treatment of two and three days old eggs, respectively.
Pupal mortality percentages were (46.18, 33.33, 21.43 and
5.83%) and (28.47, 20.0, 25.0 and 20.0%) resulted from
treatment two and three days old eggs with 1ufenuron,
flufenoxuron, pyriproxyfen and hexaflumuron, respectively.
Concerning, rate of adults emergence, the percentages
were (91.04, 40.85, 33.82 and 28.21%) and (77.92, 56.99, 54.87
and 57.14%) recorded after treatment of two and three days old
eggs with hexaflumuron, pyriproxyfen, 1ufenuron and
flufenoxuron, respectively.
Malformed adult percentages were (50.0, 41.12, 17.65
and 2.1%) and (37.5, 33.33, 30.0 and 1.67%) produced after
treatment of two and three days old eggs old by pyriproxyfen,
flufenoxuron, hexaflumuron and lufenuron, respectively.
3- Spodoptera littoralis :
Larval mortality percentages, tebufenozide was more
effective on one day old eggs (92.5%) while, lufenuron was
more effective on two and three days old eggs where it caused
100.0%mortality for larvae hatched from these eggs.
While, for pupation percentages, the highest percentage
pupation were (85.45, 77.75 and 77.34%) in the case of
pyriproxyfen treatment after one, two and three days old eggs,
respectively.
For, pupal mortality percentages, the highest were (49.5,
and 47.61%) recorded after treatment of one and two days old
Summary -161-
eggs by flufenoxuron, respectively. On the other hand, it was
27.27% produced after treatment three days old eggs with
hexaflumuron.
While, for deformed pupae recorded (44.0,33.34,25.68
and 22.66%) were produced after treatment two and three days
old eggs with pyriproxyfen, tebufenozide and hexaflumuron,
respectively.
Concerning, the adult emergence percentages, those were
(49.99,46.86,45.94 and 21.56%) and (55.56,51.4,50.07 and
48.0; %) recorded after treatment of two and three days old eggs
by tebufenozide, pyriproxyfen, hexaflumuron and flufenoxuron,
respectively, compared with 88.86% for untreated eggs.
Tebufenozide caused the highest percentages of
malformed adult percentages (65.18 and 39.14%) resulted from
treatment one and two days old eggs, respectively.
Part-l V. Effect of insect growth regulators on the
reproductive potential of S. littoralis:
The average number of eggs of crosses (TYxUe) and
(UYxTe) were 664 and 368.4 when moths were fed on
fenoxycarb sugar solutions while, for the control were 709.6
eggs. The highest percentage of sterility was obtained with cross
(Me) feeding on pyriproxyfen 79.73% followed by cross
(TY xUe) feeding on fenoxycarb while the lowest level of
sterility was 3.56% resulted from feeding males of S. littoralis on
50 ppm of chlorfluazuron in sugar solution.
Part. V-Effect of some growth regulators on the embryonic
development:
Fenoxycarb, pyriproxyfen and tebufenozide have direct
effect on the embryological development of the egg between the
Summary -162-
4thhour and the 11 thhour. It was between the 4 thhour and tenth
hour in the case of fenoxycarb pyriproxyfen, but in the c~se of
tebufenozide the direct effect was between 5 thhour and 11 hour.
While, in the case of the other 4 tested IGls, the effective time of
treatment was between the 14 thhour and 19 thin the case of
diflubezuron and it was between the 20 thhr. and 42nd hour, in the
case of flufenoxuron but in the case of hexaflumuron and
lufenuron the effective time for treatment was late (between the
23 rd hr. and 36 thhr. and between 30th hour and 42 nd hour,
respectively.
That meant that the embryology of the tested eggs is
affected during a fixed time of development, this time was in the
early age in the case of JHAs (between the 4 thand 11 thhours, but
this time was late in the case ofIGls, normally in the second day
of embryonic development.
Part Vl.The embryonic development of the cotton leaf worm
S. littoralis:
from the result about the bioactivity of different tested
compounds at different age of the embryonic development it
seem clearly that the JHA compounds tested (Pyriproxyfen,
tebufenozide and fenoxycarb) have direct effect on the cleavage
nuclei, on blastoderm and the germ band.
No remarkable, morphological changes were detected
after treatment in cleavage nuclei or in blastoderm and germ
band.