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Effects of Buxus chinensis extract, Bacillus thuringiensis and nuclear polyhedrosis virus (NPV) mixture on certain biological aspects of Spodoptera littoralis were studied against the 2nd and 4th larval instars of S. littoralis. The mixture of the three compounds was the most toxic against the 2nd and 4th instar larvae, where it caused high percentage of mortality, while B. thuringiensis (Dipel 2x) and nuclear polyhedrosis virus (NPV) mixture induced a slight effect against the 2nd and 4th instars. Regarding the ethanolic extract of Buxus chinensis leaves, it was more effective than B. thuringiensis (Dipel 2x) or nuclear polyhedrosis virus (NPV) in respect of pupal mortality and larval , pupal and adult duration. This plant extract also reduced the fecundity and fertility of females emerged from the treated larvae of S. littoralis.

Bacillus thuringiensis strains that belong to B. thuringiensis, B. kurstaki and soil-isolated B.t. were assessed in the following phytopathogenic: Rhizoctonia solani, that had their mycelial growth decreased after incubation in the presence of the bacterial strains. The bacteria have also pathogenic effect against the insect pest Spodoptera littoralis. The isolate B.t. D-1 and the B.t. kurstaki HD-203 were found to be inhibiting R. solani, the strain B. kurstaki HD-203 displayed the highest percentage of inhibition (64%) and B.t. D-1 showed 49% of inhibition. Antagonistic activity was maintained up to pH 8.5, and the antifungal activity was stable to heat at 70 °C for 1 h. Minimal inhibitory concentrations were 152 and 131 μl/ ml for B.t. D-1 and B. kurstaki HD-203, respectively. The two strains also have high efficacy against S. littoralis larvae, B.t. D-1 gave 70% and the B. kurstaki HD-203 strain gave 80% mortality after seven days of treatment.

The effect of stress conditions on viability and activity of the recombinant E. coli, that contains cryIAC gene, which encodes a crystal toxin specific to Spodoptera littoralis, was tested. Solar radiation showed the worst effect on both viability and activity against the larvae of S. littoralis. The drastic effect also happened when recombinant E. coli was exposed to heat treatment at 50oC for more than 5 min. and to high concentrations of sucrose (> 20 % for more than 2 days). Also, the same effect happened when cells were exposed to NaCl > 5 %, even after one day of exposure. The viability of E. coli cells after preservation by freezing under glycerol, lyophilization and encapsulation indicated that, freezing was the best method for keeping both viability and activity of cells till 9 months post preparation.

This research aims at determining the level of fish farming as aggregate of its two sub levels (a) fish farm (b) fish farmer awareness and determining the level of water pollution of fish farm, as well as identifying the correlated factors as well as identifying the most important problems facing the respondents in fish farming. This research was conducted on Mansour area, sector of El-Hamoul Kafr Al-Sheikh governorate the biggest area for cultivation in the province. A systematic random sample of (63) fish farm, was selected in four villages (Com Elteen, Elbehera, Alshaimaa, Almagd) using the Morgan equation. Data were collected from respondents using a personal questionnaire interviews, the arithmetic mean, standard deviation, simple Person, correlation and multiple correlation and regression analysis (Step-Wise) were used to analyze data statistically as well as frequencies and percentages .The main results of this research revealed that:1 – (53.97%), of the respondents were in moderate level of fish farming inputs. 2- (59.84%) of the respondents were in high level of fish farming awareness. 3- (44.44%) of the respondents were in moderate level of fish farming , as a result of the two variables (a), and (b) 61.2%. 4- (60.32%) of the respondents were in moderate, level of, water pollution of fish farm . 5- Nine problems were facing the respondents with regard to fish farming with percentages ranged between (4.76% to 98.41%,) some of their could be ranged in descending order as follows : higher prices for feed ,control feed companies and traders in the market, lack of irrigation water in summer, pollution of irrigation water resulting from the waste of factories and agricultural drainage.

Control methods were carried in Baltiem district, Kafrel-Sheikh Governorate from times during both Spring and Summer plantations, 2012. The efficacy of these control methods was recorded on the basis of reduction percentage in the larvae after periods of 2, 5, 7, 10 days from each application. The obtained results revealed that the highly increase in the reduction was occurred in Summer plantation verification with the number of larvae in Spring plantation. Based on reduction percentages in the number of larvae, the efficacy of the tested treatments could be descendingly arranged as follows Bacillus thuringiensis + Neem, B. thuringiensis + Trichogramma evanescens + mass trapping, B. thuringiensis + Trichoderma harzianum, T. harzianum + Neem, T. harzianum + mass trapping and T. evanescens + Neem. The corresponding value were 91.88, 90.18, 87.89, 85.69, 80.75 and 84.82 % for the above treatments, during Summer plantation and 88.49, 86.03, 84.78, 83.01, 79.88 and 82.82 % during Spring plantation. On the other hand, using baited traps of males moths using synthetic sex pheromones recorded the highest relative percentage were 10.91 and 10.76 % in Spring and Summer plantation, respectively. Where the lowest one recorded 2.74 and 2.71 % in Spring and Summer plantation. The highest healthy yield production recorded 9.555 ton/feddan in case of using B. thuringiensis + Neem, whereas the lowest healthy yield production recorded 5.580 ton/feddan when using T. evanescens + Neem. The corresponding general means of cost benefit 3317 and 1589L.E/feddan, respectively. On the other hand, the healthy yield production in the untreated plot recorded 1.555 ton/ feddan. Key words: Tuta absoluta, sex attractant pheromones, microbial insects, botanical extracts, Trichogramma.

A Bacillus thuringiensis isolate (KIII), isolated from Egyptian soil, was produced in liquid culture using yeast extractmolt- glucose medium, where the spore-crystal complexes were recovered. The complexes were formulated into three granule formulations, then the toxicity of the isolate was evaluated in laboratory by bioassay against the cotton leafworm S. littoralis. Results exhibited that, the best formulation for keeping biological activity (both efficacy and survival) of B. thuringiensis was the alginate granules. Bioassays of the formulation containing Congo red (as UV- protectant), indicate the superiority of this additive to other in improving the effectiveness of B.t. under exposure to sunlight. Also, adding molasses + soybean flour exhibited the highest efficacy when using as feeding stimulants. Zinc sulphate also showed a remarkable effect in enhancing B.t. potency and viability.

The biological and biochemical effects chloropyrifos, camphor extract and their combination were studied against the 4 th instars of Spodoptera littoralis under semi-field conditions. The results indicated that the LC50 for chloropyrifos was 0.08 ppm and 13.3 x 10 3 ppm for the camphor extract. The estimated Co-toxicity factor was 13.2 So, there is an additive effect between camphor oil and chloropyrifos against S. littoralis. Oil extract of camphor prolonged larval and pupal duration also the same effect happened when using mixture of camphor extract and chloropyrifos. This prolongation was accompanied with a reduction in pupal weight of the treated larvae. While when using chloropyrifos only the larval and pupal duration were shortened Also % of pupation and % of adult emergence were more decrease in plant extract and insecticide mixture than each compound alone. Biochemical studies showed that, total protein content of larval instars decreased by 31, 26 and 13.5 % for camphor extract, chloropyrifos and its combination, respectively. Also, the activity of acid phosphatase, α-esterase was significantly decreased. Where the alkaline phosphatase, activity increased When compared with control.