الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
The target of the present study is conversion of wastes to
economic products as insecticides which can be used on large scale in
controlling pests in the entire world, for the control of Egyptian cotton
leaf worm, Spodoptera littoralis (Boisd). Therefore, The present study
aimed to evaluate the insecticidal activity of three newly compounds
extracted from wastes from natural origin, Cyano acetyl urea (CAU),
Benzimidazolyl acetyl urea (BAU) from urea and Cyano acetyl
hydrolyzate (CAH) from rice straw, on the Egyptian cotton leaf worm
(Spodoptera littoralis) (Boisd), through exposure of second and fourth
instar larvae to castor bean leaves which immersed in different
concentrations of tested compounds. These compounds were assessed
for their toxicity, biological and latent effects. In addition, immune
response, biochemical, and molecular effects were investigated in the
treated larvae.
1. Insecticidal activity:
Data cleared that, LC25 estimates of 2nd instar larvae ranged
from 0.0425 to 0.151, from 0.111 to 0.252 and from 0.006 to 0.016
for larvae treated with CAU, BAU and CAH, respectively. While
LC50 ranged from 0.302 to 0.756, from 0.457 to 0.898 and ranged
from 0.062 to 0.094 for those treated with CAU, BAU and CAH,
respectively. The LC70 ranged from 1.092 to 3.3603, from 1.193 to
2.769 and ranged from 0.279 to 0.500 for larvae treated with CAU,
BAU and CAH, respectively.On the other hand the LC25 estimates of 4th instar larvae ranged
from 0.092 to 0.154, from 0.156 to 0.225 and ranged from 0.009 to
0.021 for larvae treated with CAU, BAU and CAH, respectively.
While, LC50 ranged from 0.447 to 0.594, from 0.583 to 0.752 and
ranged from 0.083 to 0.012 for larvae treated with CAU, BAU and
CAH, respectively. The LC70 ranged from 1.288 to 2.009, from 1.445
to 2.159 and ranged from 0.339 to 0.627% for larvae treated with
CAU, BAU and CAH, respectively. Hence, the present results
indicated that (CAH), was the most efficient extract followed by
(CAU), and then (BAU).
2. Biological Studies:
A laboratory experiment was carried out to estimate the
biological aspects (pupation, pupal weight, pupal duration, adult
emergence, fecundity and fertility) of 2nd and 4th instar larvae after
treated with the above mentioned compounds. Morphogenic
abnormalities were evaluated as well.
2.1. Biological activities of CAU, BAU, and CAH against 2nd instar
larvae of S. littoralis.
Data indicated that the response was positively-related to
concentrations, Larval mortality increased significantly with increase
in the concentrations. Pupation percentages and pupal weights
declined dramatically through successive ascending concentrations.
The pupal durations were increased significantly while the
percentages of the adult emergence were reduced significantly with
ascending concentrations. The total inhibition was increased with
increasing concentrations. Fecundity and fertility was decreased with
treatment as well.2.2. Biological activities of CAU, BAU, and CAH against 4th instar
larvae of S. littoralis.
Data cleared that the larval mortality increased significantly
with increase in the concentrations as expressed in corrected
percentages. There was a great decline in pupal percentages through
successive concentrations. The weights of the resulted pupae were
affected also, While, the pupal durations were increased. The
percentages of the adult emergence were declined. Fecundity and
fertility were decreased and the O.D.I. was increased as well.
3. Morphogeneitc effect.
Treatment of 4th larval instar of S. littorais with CAU, BAU and
CAH resulted in different morphogenic abnormalities and many
aberrations had been induced in all stages. CAU treatment for
example, induced surrounding of 6th instar larva by old exuvium,
shrinked pupa failed in shedding off the larval exuvium, poorly
deceloped wings and many other abnormalities. In BAU treatment for
example, the pupal cuticle remained adhered to the moth’s body. CAH
showed 6th instar larva surrounded by old exuvium of 5th instar larva
and pupal-adult intermediate, head and thorax enclosed by old cuticle
of pupa. In all cases the rate of malformations occurrence was
directly proportional to the concentration used, the sequences of
events were identical.
4. Effects of CAU, BAU, CAH on haemocytes of 4th instar larvae
of S. littoralis
4.1. Changes in total haemocyte counting:
The mean of total haemocytes counts in haemolymph of untreated 6th
larval instar was 9430±35.78 cells/mm3. Data indicated an increase in total haemocytes of treated ones with CAU, at LC25 and LC50,
BAU at LC25 and CAH at LC25, LC50 of CAH the percentages of
change were: 19.01, 14.31, 1.90, 21.00 and 14.55, respectively. While
a reduction was noticed in total haemocytes of treated larvae with:
CAU (at LC70), BAU (at LC50, LC70) and CAH (at LC70) comparing
the control group: the percentages of changes were: -27.78, -12.93, -
30.11 and -6.57 respectively.
4.2. Chages in differential haemocytes counts:
The mean percentages of plasmatocyte, prohemocyte,
granulocyte, spherulocyte and oenocytoid in untreated group were 42,
33, 15, 9 and 1 respectively.
The percentage of plasmatocyte increased relative to control in
larvae treated with CAU (at LC25), BAU (at LC25) and CAH (at LC25,
LC50 and LC70) since these percentages were: 45.55, 45.64, 56.1, 62.0
and 65.12. The percentage of plasmatocyte decreased in other
concentrations of the mentioned compounds.
Also, the percentages of prohaemocyte counts increased relative
to control in larvae treated with CAU (at LC25, LC50 and LC70) BAU
(at LC50 and LC70): 34, 44.5, 39.12, 38.0 and 50.3 in respectively. In
contrast, the percentages of prohemocyte count decreased relative to
control in larvae treated with in other concentrations of the mentioned
compounds.
As to granulocytes, data cleared reductions in all concentrations
for all compounds except for BAU at LC50 as they increased slightly
(15.12%).
The spherulocytes percentages were increased for larvae treated
with CAU (at LC25, LC50 and LC70) BAU (LC70) and CAH (at LC25)as the percentage were: 9.67, 11.28, 9.14, 9.2 and 12.08 as
respectively, compared with control group. The spherulocytes
percentages were decreased in other concentrations.
All the percentages of oenocytoid counts were increased (2.0,
1.84, 2.02, 1.1, 2.0, 1.35, 1.22 and 2.0%) for those treated with CAU
(at LC25, LC50 and LC70) , BAU (at LC25, LC50 and LC70) and CAH (
at LC25 and LC50) except for CAH (at LC70) as it did not change
comparing control count.
5. Biochemical studies:
This section of the study is concerned with biochemical effect of
(CAU),(BAU) and (CAH) on 4th larvae instar of S. littoralis, which
treated with LC25, LC50 and LC70 values of tested compounds, The
protein pattern, and some enzymatic activities of S. littoralis were
screened.
5.1. Native protein
A maximum number of 46 bands were detected at approximately
Rf ranging between 0.03 to 0.75. The epigenetic distance between
control and treated samples {LC25, LC50 and LC70 of (CAU), LC25,
LC50 and LC70 of (BAU) and LC25, LC50 and LC70 of (CAH)} were
(0.76, 0.58, 0.48, 0.38, 0.69, 0.69, 0.85, 0.69, 0.62) respectively.
5. 2. Glycoprotein pattern:
A maximum number of seven bands were detected with Rf ranging
between 0.07 to 0.28. The epigenetic distance between control and
treated samples were recorded 1.00 for all samples except for those
treated with CAU at LC50 (0.67).
5. 3. Lipoprotein pattern:A maximum number of three bands, Rf ranging between 0.03 and
0.05. The epigenetic distance between control and treated samples
{LC25, LC50 and LC70 of (CAU), LC25, LC50 and LC70 of (BAU) and
LC25, LC50 and LC70 of (CAH)} were (1.00, 1.00, 1.00, 0.00, 0.00,
1.00, 1.00, 0.00, 1.00) respectively.
5.4. Fractin protein (SDS-PAGE)
A maximum number of 61 bands were revealed with molecular
weight (Mw) ranging between 313.53 and 4.14. The epigenetic
distance between control and treated samples LC25, LC50 and LC70 of
(CAU), LC25, LC50 and LC70of (BAU) and LC25, LC50 and LC70 of
(CAH) (0.54, 0.71, 0.55, 0.44, 0.60, 0.64, 0.69,0.69,0.53,0.7)
respectively.
5.5. Isozyme Analysis:
5.5.1. Esterase by -naphthyl
A maximum number of 36 bands were detected in control and
treated larval samples with Rf ranging between 0.01 to 0.28. The
epigenetic distance between control and treated samples {LC25, LC50
and LC70 of (CAU), LC25, LC50 and LC70of (BAU) and LC25, LC50 and
LC70 of (CAH)} were (0.62, 0.76, 0.82, 0.75, 0.62, 0.50,
0.47,0.87,1.00) respectively.
5.5.2 Esterase by -naphthyl:
A maximum number of 39 bands were detected in control and
treated larval samples with Rf ranging between 0.01 to 0.92. The
epigenetic distance between control and treated samples treated with
LC25, LC50 and LC70 of (CAU), LC25, LC50 and LC70 of (BAU) and
LC25, LC50 and LC70 of (CAH) were (0.89, 0.79, 1.00, 0.89,
1.00,1.00,1.00,1.00,0.76), respectively..2.3. Malic enzyme pattern (Mal):
There was maximum number of 6 bands recorded in control and
treated larval samples with Rf ranging between 0.06 and 0.22. The
epigenetic distance between control and treated samples {LC25, LC50
and LC70 of (CAU), LC25, LC50 and LC70 of (BAU) and LC25, LC50
and LC70 of (CAH)} were (1.00, 0.50, 0.50, 0.50, 1.00, 1.00, 1.00,
0.50, 1.00)respectively.
5.2.4. Malate dehydrogenase enzyme pattern (Mdh):
A maximum of 14 bands were detected in control and treated
larval samples with Rf ranging between 0.08 and 0.46. The epi genetic
distance between between control and treated samples {LC25, LC50
and LC70of (CAU), LC25, LC50 and LC70 of (BAU) and LC25, LC50 and
LC70 of (CAH)) were (0.33, 0.33, 0.43, 0.43, 0.43, 0.71, 0.71, 0.71,
1.00), respectively.
5.2.5. Alcohol dehydrogenase pattern (Adh):
A maximum number of 9 bands were detected at approximately
Rf ranging between 0.02 and 0.18. The between epigenetic distance
between control and treated samples at LC25, LC50 and LC70of (CAU),
LC25, LC50 and LC70of (BAU) and LC25, LC50 and LC70 of (CAH)
were (0.50, 0.50, 0.50, 1.00, 1.00, 1.00, 1.00, 1.00, 1.00), respectively
5.2.6. Aldehyde oxidase pattern (Alo):
A maximum number of 17 bands were detected at approximately
Rf ranging between 0.01 and 0.28. The epigenetic distance between
LC25, LC50 and LC70 of (CAU), LC25, LC50 and LC70 of (BAU) and LC25, LC50 and LC70 of (CAH) samples and their control were (0.75,
1.00, 1.00, 1.00, 0.71, 1.00, 1.00, 1.00, 0.75) respectively.
5.2.7. Peroxidase enzyme pattern (Px):
A maximum of 27 bands were recorded in control and treated
larval samples with Rf ranging between 0.04 and 0.84. The epi genetic
distance between control and treated samples at LC25, LC50 and LC70
of (CAU), LC25, LC50 and LC70 of (BAU) and LC25, LC50 and LC70 of
(CAH) were (0.71, 0.57, 0.71, 0.86, 0.69, 0.69, 1.00,1.00,1.00),
respectively.
5.2.8. Acid phosphatase pattern (ACph):
A maximum number of 37 bands, Rf ranging between 0.02 and
0.94. The epigenetic distance between LC25, LC50 and LC70of (CAU),
LC25, LC50 and LC70of (BAU) and LC25, LC50 and LC70 of (CAH)
treated samples and their control were (0.67, 0.87, 0.76, 0.37, 0.25,
0.47, 0.60, 0.86, 0.76) respectively.
6. The molecular study:
The other objective of this study is to evaluate the potential of the
random amplified polymorphic DNA (RAPD) assay for the detection
of genetic polymorphism between control and treated S. littoralis
larvae, which have been exposed to the tested compounds at both
LC25 and LC70. Five primers namely: OP-01,OP-02, OP-03, OP-04,
and OP-05 were used in this study. These five primers generated a
maximum of 26, 24, 20, 13 and 23 bands, respectively. RAPD profiles
generated by these primers revealed differences between control and
treated samples with visible changes in number and size of amplified
DNA fragments.Polymorphism ranged from 44.4 to 100% as screened by the
five primers among all samples. Taking all data together, higher
polymorphism was recorded at LC70 (77.8, 84.4, and 86.4%)
comparing corresponding values at LC25 (69.6, 80.3 and 79.4) for
larvae treated with CAU, BAU and CAH, respectively. Based on
LC70, the highest polymorphism (86.4%) was observed in those
treated with CAH comparing those either treated with CAU (77.8%)
or with BAU (84.4%). Definitely, RAPD data confirmed the
susceptibility test as well as the morphological study and suggest that
DNA damage and the possible occurred mutations may appear to be
the main factor influencing the evident polymorphism between control
and treated larvae.