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REPRODUCTIVE TOXICITY OF BACILLUS THURINGIENSIS BIO-PESTICIDE IN MALE ALBINO RATS Texto completo
2009
The present study is a trial to investigate the toxic effects of the bio-pesticide Bacillus thuringiensis (Bt) on male reproductive system of rats. Rats received dietary doses each approximately equivalent to 1/10 or 1/100 of the LD50 value of the Bt bio-pesticide (Agerin) for 90 consecutive days. Sex organs weight, semen picture, concentrations of the hormones [i.e., testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH)], and histopathological changes in testes were the criteria used to evaluate the reproductive toxicity on the treated rats. Btat the higher dose caused a significant decrease in the weight of testes and seminal vesicles as compared with control. Both Bt doses decreased sperm count associated with an increase in the morphologically abnormal spermatozoa; however sperm motility was significantly decreased in treated rats with the higher dose only. The concentration of serum testosterone was significantly reduced in both treated groups; however LH and FSH levels were significantly reduced in treated rats with the higher dose. Histopathological examination of Agerin-treated male rat's testes revealed that both Bt doses caused testicular degeneration in a dose-dependent manner. In conclusion, Agerin may decreases fertility in adult male rats by affecting the concentrations of pituitary gonadotrophins, testosterone and thus subsequent spermatogenic impairment
Mostrar más [+] Menos [-]DISAPPEARANCE OF AZOXYSTROBIN, CYPRODINIL, FLUDIOXONIL, FENHEXAMID AND MYCLOBUTANIL IN STRAWBERRY FRUITS UNDER FIELD CONDITIONS Texto completo
2009
A field experiment was carried out at Nubariah region Alexandria desert road located at 120 Km from Cairo, (Egypt) during 2005-2006 to study the degradation rates of five fungicides azoxystrobin, cyprodinil, fludioxonil, fenhexamid, and myclobu-tanil in strawberry fruits after application with their recommended rates under field conditions. The samples were collected in successive intervals after spraying and transported to Bioforsk refer-ence Lab, Ǻs, Norway for analysis by GC/MS. The fungicide residues on strawberry showed different degradation rates after treatment, with first-order kinetics. Half-lives (t0.5) were 1.92, 4.99, 3.68, 6.02 and 5.17 days for azoxystrobin, cyprodinil, fludioxonil, fenhexamid and myclobutanil, respectively.
Mostrar más [+] Menos [-]STUDIES ON NEEM SEED KERNEL EXTRACTS AS OVIPOSITION DETERRENTS AND OVICIDAL COMPOUNDS FOR THE COTTON LEAF WORM MOTHS, Spodoptera littoralis (Boisd.) Texto completo
2009
H.A Gomaa
Mated female moth of the cotton leafworm, S. littoralis laid a total number of 1564.22 eggs during its whole life. In a free choice test, treating N. oleander leaves (as an oviposition site) with an aqueous extracts of neem seed kernel solutions extracted by different organic solvents reduced the number of deposited eggs on it. The lowest number of eggs was recorded when methanol was used for extraction, followed by chloroform, and the highest was, however, obtained after using benzene, butanol and ethyl acetate. The number of deposited eggs decreased as the concentration of any tested neem extract increased to reach the minimum at 0.2%. This means that the most deterred neem seed kernel extract is that which extracted with methanol at the concentration of 0.2%.Hatchability percentage of S. littoralis eggs greatly affected by the type of organic solvents used for neem extraction and the concentration of each extract on treated N. oleander leaves. The lowest hatchability was recorded after using methanol, followed by chloroform.On the other hand, an increase in neem seed kernel extract concentration caused an obvious decrease in egg hatchability.
Mostrar más [+] Menos [-]CHANGES OF SOME SOIL PHYSICAL AND HYDROPHYSICAL CHARACTERISTICS IN RESPONSE TO DIFFERENT SPRINKLER TYPES AND NOZZLE SIZES Texto completo
2009
Walaa El-Shalakany | M.O El-Zakaziky | A.M. El-Araby | E.A. El-Sahhar | Y.E Arafa
Soil characteristics' degradation had been considered as one of the most important problems that face the agricultural development processes under arid and semi-arid conditions due to non-suitability of the applied technologies and techniques, attributed to management considerations. Consequently, higher crop yield and quality reduction had been occurred due to the degradation of the plant healthy media (soil). Therefore, the goal of this investigation was to monitor the change detection of some soil physical and hydrophysical characteristics under sprinkler irrigated agriculture. However, the terminal objectives were to evaluate and monitor some soil characteristics changes (soil bulk density, hydraulic conductivity and soil penetration resistance) under different mode of action of sprinkler types (rotating and impact sprinkler) and corresponding nozzle sizes (small and large sizes). Hereby, field experiments were carried out for two seasons (2006 and 2007) in the Desert Experimental Farm of Faculty of Agriculture, AinShamsUniversity which is located at El-Bustan region, Behaira Governorate. Results revealed that soil characteristics were highly affected with the sprinkler mode of action and corresponding nozzle sizes. However, a power function proportion of soil penetration resistance with respect to applied rotating and impact sprinkler types and corresponding small and large nozzle sizes, had been observed and analyzed. Therefore, data analysis speculated that, selection of the appropriate sprinkler types under diverse field conditions and situations such as: crop type and design criteria of sprinkler irrigation systems, have to be considered for good agricultural development processes under Egyptian newly reclaimed regions.
Mostrar más [+] Menos [-]RELATIVE IMPORTANCE OF FIBER PROPERTIES AFFECTING YARN HAIRINESS IN SOME EGYPTIAN COTTON VARIETIES Texto completo
2009
Kh.M.M Hussein | M.H . Mahmoud | A.A . Hassan
undesirable, depending on the application for which the yarn is being used. Hairy yarns provide good heat retention and a softer hand (feel) for finished fabrics, and except for a few special cases, when it is an excessive degree of hairiness, yarn hairiness is an undesirable property in yarn and can cause serious problems in both yarn production and in subsequent textile processes. This search was carried out to investigate the most important fiber properties i.e. short fiber content (SFC w %), maturity ratio, micronaire value, uniformity index (UI %), fiber length (UHM) and fiber strength (g/tex) which correlated with yarn hairiness and also their relative contributions in yarn hairiness under study by using four Egyptian cotton varieties during season 2008, namely; Giza88, Giza86, Giza80 and Giza90 spun into carded ring and compact yarns at twist multiplier 3.6 and two into counts according to the following: ring yarns were processed to carded yarns Ne 50 and 60. Compact yarns were also processed to carded yarns at the same counts. The most important results were: 1- Yarns manufactured by the carded ring spinning frame are characterized by higher hairiness mean values in all studied varieties in comparison with those of carded compact frame. 2- The correlation coefficients have positive signs and are very high between hairiness in yarns and short fiber content (SFC w %), on the contrary the correlation coefficients have negative signs being high or very high between maturity ratio, micronaire value, uniformity index (UI %), fiber length (UHM) and fiber strength (g/tex) and yarn hairiness in all varieties. 3- Stepwise regression procedure was employed to determine the most effective independent variables which make the maximum contributions to the coefficient of determination (R²). The rate of improvement in yarn hairiness index due to decrease short fiber content (the larger the share of fibers in the shorter length the higher is the hairiness index), increase fiber strength (more mature fiber) and increasing fiber length (the larger the share of the fibers in longer length the lower is the hairiness index
Mostrar más [+] Menos [-]CHEMICAL COMPOSITION OF CAMEL'S COLOSTRUM AND MILK IN UNITED ARAB EMIRATES Texto completo
2008
Rea H. Omer | A.H Eltinay
The chemical composition of 350 samples from camel's colostrum and milk in United Arab Emirates were studied. Results of colostrum showed 6.19 for pH, 1.041g/ml for density, 3.1% for fat, 4.95% for protein, 4.4% for lactose, 12.88% for total solids, 10.55% for non fat total solids, 1.11% for ash, 87% for moisture .For ma-ture milk, data were 6.6 for pH, 0.133% for acidi-ty, 1.028g/ml for density, 3.2% for fat, 2.4% for protein, 4.6% for lactose, 11% for total solids, 7.88% for non-fat total solids, 0.88% for ash, and 88.9% for moisture. The minerals contents in camel colostrum were (mg/100mg) as follows: 103 for calcium, 15.4 for magnesium, 14.0 for sodium, 128 for potassium, 0.25 for iron, 0.17 for copper and 43.4 for inorganic phosphate. Elements in mature camel milk were (mg/100mg) as fol-lows: 74.67 for calcium, 3.4 for magnesium, 42.36 for sodium, 136.64 for potassium, 0.18 for iron, 0.04 for copper, 0.02 for manganese, 0.3 for zinc and 38.4 for phosphorus.
Mostrar más [+] Menos [-]USE OF ESSENTIAL OILS FOR CONTROLLING BACTERIAL ANGULAR LEAF SPOT DISEASE OF CUCUMBER Texto completo
2008
Gomah A A
Activity of commercially and purified essential oils of aloes, anise, black cumin, caraway, carna-tion, cumin, fennel, garlic, jojoba, lavender, onion, rue and thyme were tested against growth of Pseudomonas syringae pv. lachrymans, caused bacterial angular leaf spot disease of cucumber, in vitro and in vivo. Three essential oils had an inhib-itory effect, based on the determination of the min-imum inhibitory concentrations (MICs 0.25-2.0%). Carnation, fennel and thyme were inhibito-ry at MIC 0.5%. The three mentioned oils showed considerable variation in the inhibitory effect by the disk diffusion method, though the recognized similarity in fumigation treatments. The greatest activity was recorded with thyme (18mm) followed by carnation (15 mm) while fennel showed the low-est effect (9mm). Soaking cucumber seeds of differ-ent cultivars in 2% emulsified oils for a period rang-ing from 0.25 to 4 hours significantly decreased the percentage of germination. Shorter duration of seed soaking, 0.25 to 0.5 hours, showed lower deleterious effect on germination and fennel oil showed greater harmful effect. In greenhouse experiments, the three oils significantly controlled the disease incidence compared to the check treatment, being more pro-nounced for thyme oil followed by fennel and carna-tion oils. Analysis of the essential oils in concern showed eugenol, dieugenol, linolenic acid, methyl chavicol (estragol), anisole and thymol, as an active ingredients.
Mostrar más [+] Menos [-]EFFECT OF VAPOR GARD AND CALCIUM CHLORIDE TREATMENTS ON KEEPING QUALITY OF NAVEL ORANGES AT DIFFERENT STORAGE TEMPERATURES Texto completo
2008
Hanafy Ahmed A.H | H.M. Rashad | Samia, G. El-Oraby | F El-Wakil
The experiments were conducted in two suc-cessive seasons (2004 - 2005) on Washington Na-vel orange fruits to study the effect of cold storage conditions on reducing postharvest losses and im-proving keeping quality for the export mar-ket.Fruit samples were obtained from El–Fayoum governorate, Egypt and treated with vapor gard (VG) 2%, calcium chloride (CaCl2) 4% or vapor gard 2% + calcium chloride 4%. Fruits were stored at 2 or 8 ºC for 60 days and the last group was stored at 2 ºC for 30 days and transferred to be stored at 8ºC for another 30 days at R.H. 85-90%.The results revealed that during storage fruits treated with Vapor gard (2%) alone or with calci-um chloride (4%) + Vapor gard (2%) had been in good quality as well as it caused a pronounced increase in peel color and fruit firmness, while fruit weight loss and juice percentage were de-creased. In addition, it caused a significant in-crease in ascorbic acid, total sugar and calcium concentration, but there is no significant effect in T.S.S. / acid ratio. While, free amino acid, total soluble phenols and free proline concentrations were decreased. Furthermore, the fruits storaged at 2º + 8ºC caused a pronounced increase in fruit firmness, while fruit weight losses, juice percent-age and peel color were decreased. Also, it caused a pronounced decrease in T.S.S. / acid ratio, total sugar, total free amino acid, total soluble phenols and free proline concentrations, but there is no significant effect on calcium concentration. In addition, there is an increase in ascorbic acid con-centration. Generally, the results revealed that Vapor gard either alone or combired with calcium chloride dipping treatments and stored at 2º + 8ºC had better results in improving fruit quality and decreasing total fruit losses compared with control or calcium chloride treatment alone at other stor-age temperatures and this was also accompanied by changes in various metabolic and physiological processes of orange fruits.
Mostrar más [+] Menos [-]STUDIES OF PHENOLIC COMPOUNDS AND PROTEINS AS A MARKER OF THE BIODIVERSITY OF VICIA FABA L Texto completo
2008
Belattar R | Merghem R | Boudour L
A collection of 12 varieties of broad bean (Vicia faba L.) was studied. This was curried out to see the variation of phenolic compounds (tannins) and proteins of the seeds of Vicia faba L. This study gave the following results - At the biochemical level; according to our results one observed a high content in proteins within the species of Vicia faba L. - The electrophoresis of total proteins confirmed the richness of proteins of Vicia faba L [albumins (67 kDa), Globulins, Vicilline (50 kDa)]. - Finally the phytochemical analysis (phenolic compounds) allowed us to confirm the richness of the colored seeds in phenolic compounds (condensed tannins) "949 T (183±9.66), Aquadulce (132.19±1.53)". The effect of time (the factor of the environment) inflates on the coloring of the seeds (oxidation) and on the polymerization of tannins.
Mostrar más [+] Menos [-]OPTIMIZATION OF A CULTURE MEDIUM FOR BIOMASS AND δ-ENDOTOXIN PRODUCTION BY A RECOMBINANT ESCHERICHIA COLI STRAIN Texto completo
2008
Rawia F. Gamal | Al-Fateh R. | Abeer Mohammed | M. El-Sawy
A recombinant strain of Escherichia coli harboring a plasmid containing the Bacillus thuringiensis δ-endotoxin synthesis gene, was tested for its efficacy to synthesize δ-endotoxin, in a complex medium containing sucrose and yeast extract. Also, the recombinant E. coli strain was tested for its efficacy against the 2nd instars of Spodoptera littoralis. The recombinant strain of E. coli showed a good activity against the 2nd instars of S. littoralis, the mortality was 70 % after 7 days at room temperature. A high cell biomass (8.8gL-1) and δ-endotoxin concentration (6.8 mg L-1), were obtained by the shake flask culture (100 ml medium/250 ml flask, at 200 rpm), of the recombinant E. coli in modified MR medium containing sucrose (20g/L), as carbon source and yeast extract as nitrogen source, in the presence of CaCO3, K2HPO4, MgSO4, FeSO4 and ZnSO4 as mineral salts. The best pH values for cell biomass production and endotoxin production were 7.0 and 7.5, respectively. The corresponding figures for the best temperature were 37oC and 30oC, respectively. The use of some byproducts such as black-strap molasses, corn-steep liquor and cheese whey, as an alternative for carbon and nitrogen sources of medium, were found to enhance the cell growth but showed no effect on endotoxin production.
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