الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Despite the great deal of research on systemic acquired resistance to pathogens which proved to be induced by number of elicitors of biotic or chemical origin and SA is one of those cross effect on insects that this compound have bean little studied.
So the present study was carried out which includes the following main points :-
2. Evaluation of salicylic acid as inducer for systemic acquired resistance in cotton plants to different insects.
1. Effect of SA on the population of some cotton insects.
b. Exogenous application of foliar spray of SA at three concentration levels on cotton plants at early stage of growth (27 days after planting )which followed by evaluation of its role as elicitor or inducer of acquired systemic resistance of cotton plants against some cotton insects ( jassid , aphid , bollworms) under field conditions at two successive seasons; 2010 and 2011 .
b. Evaluation of the effect of SA on the performance of
the herbivore, Spodoptera littiralis under laboratory
conditions, using the mean growth rate and percentage of
cotton leaves damage as indicators.
c. Evaluation of some suggested mechanisms that explain
SAR phenomenon, peroxidese and phenoloxidase activities
as well as quantitative and qualitative determination of
total soluble protein.
II Evaluation of the effect of SA on the efficiency of some insecticides on The tested insects
1. Evaluation of the effect of SA on efficiency of some
insecticides which are recommended for field control
of these insects.
2. The effect of foliar spray of SA at S. littoralis to
three different insecticides under laboratory conditions
was evaluated.
The obtained results can concluded in the following :
VI Evaluation of salicylic acid as inducer for systemic acquire resistance of cotton plants to different insects.
1. Effect of SA on the population of some cotton insects.
a. Against cotton jassid ”Empoasca spp”
An observed increase in the insect numbers comparing with control at the initial appearance of jassid , followed by reduction along 14 days. Significant reduction nondependent on SA concentration at the two agriculture season was observed. The percentage of reduction ranged from 35.9 to 50.5% .
b. Against cotton aphid ’’Aphis gossypii’’
The same previous general trend was noticed with aphid population. A relatively increase in the absolute number that infested cotton plants at the first appearance of infestation was observed. A dramatic decrease in aphid population was recorded even in control. In general, significant reduction in aphid population was recorded which ranged from 10.3 to 25.2%.
c. Against cotton bollworms ’’Pectinophora gossypeilla’’, Earias insulana
Depending on the number of pink and spiny bollworms /100 green bolls, it could fairly concluded that a significant but slight effect of using SA was recorded at the two seasons which ranged from7.7 to 25 %.
Comparing the general means of reduction obtained with the three insects, jassid , aphid and bollworms , data reflected that the most noticeable effect (reduction of the population) was observed with jassid while the least one was recorded with bollworms. This means that , as the period between the acid application (27 days after planting) and the appearance of infestation increase of the effect becomes less observed.
2. Effect of SA on the performance of Spodoptera littoralis under
laboratory conditions.
Pre-spray of cotton plants with 1 mM SA resulted in an increase in the larval growth rate from 3.8 to 7 mg /day after 96 hrs of feeding. On the other hand 0.5 mM didn’t affect larval growth rate while a dramatic decrease from 3.8 to 0.8 mg / day was noticed with both of the mortality percentage during the course of the study (96 hrs) as well as the percentage of damage in cotton leaves after feeding for those of the larval growth. The highest percentage of damage (12.2) was recorded with 1 mM SA while the least one (3.3) was observed with 2 mM comparing with 5.5 % for the check treatment.
3. Determination of some defense proteins after spray of SA
a. determination of peroxidase and polyphenoloxidase activity indicated that 0.5 and 2 mM exhibited a degree of the enzyme inhibition while 1mM induced its activity. As for polyphenoloxidase, results referred that while 0.5, 1 mM of the acid didn’t affect the enzyme activity, 2 mM inhibited it by 50% .
b. Qualitative and quantitative change in protein
data indicated gradual increase in protein content
with increasing the acid concentration. Electrophoresis
profile exhibited more intensive bands in the common band
between all treatment beside the presence of unique band in
cotton leaves extract was treatment with either 1 and 2 mM.
II Evaluation of the effect of SA on the efficiency of some
insecticides on the tested insects.
1. Against cotton jassid ’’ Empoasca spp ’’
Sulfur was chosen for this part of study and the obtained results reflected SA has improved the efficiency of it for controlling jassid. All SA concentrations resulted in a significant increase in the percentage of reduction of jassid population while sulfur alone resulted in a percentage of reduction of 52.7 and 43.0 for 2010 and 2011 seasons respectively, the corresponding values ranged from 48.5 to 89.4 with SA application.
2. Against cotton aphid ’’Aphis gossypii’’
Carbosulfan and diafenthiuron were familiar in controlling cotton sucking insects , so they were tested here in their recommended rates. Depending on the general mean effect , it can fairly concluded that non significant to slightly significant effect on carbosulfan efficiency was recorded. Concerning the IGR’s insecticides , diafenthiuron it was proved that the application of SA 27 days after planting especially at 1 and 2 mM significantly increased of its efficiency.
3. Against cotton bollworms ’’Pectinophora gossypeilla’’, ’’Earias
insulana ’’
Three insecticides belonging to organophosphorus (chlorpyrifos), pyrthroids (lambda cyhalothrin) and carbamate (methomyl)were applied at their recommended rates. Data indicated that non significant antagonistic effect was noticed as a result of foliar application of SA at the three tested concentration on the three tested insecticides. The most noticeable effect was with 2 mM of SA.
4. The effect on oviposition of Spodoptera littoralis .
While that chlorpyrifos didn’t has any effect on egg-masses of S. littoralis it led to mortality percentage range from 60 to 68% for dead hatching. SA hadn’t any effect on chlorpyrifos efficiency on egg-masses.
4. Effect of SA on the efficiency of some insecticides on the 4th
larval instar of Spodoptera littoralis under laboratory
conditions:
Lcp lines of some insecticides against the fourth larval instar of s. littoralis which was previously priding of SA treated cotton leaves, indicated that SA previously has slightly affected the potency of effected insecticides specially at 1and 2 mM.