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USE OF WATER HYACINTH (Eichornia crassipes) IN AMELIORATION OF A SANDY SOIL Texte intégral
2008
Mubarak A R | Fattoma A M Rezik | S A Afiah
Soil fertility management is a key issue for sustaining agricultural production in dry lands. Organic resources are important for nutrient avail-ability and maintenance of soil organic matter. Sustaining fertility of arid soils necessitates in-creasing inputs of organic residues. Two experi-ments with water hyacinth were carried out to monitor (in the first; field study with litter bags) decomposition and changes in N, P, K, Ca and Mg as influenced by method of application where, in the second (greenhouse study) short-term effect on some properties of a sandy soil and early estab-lishment of fodder sorghum (Sorghum bicolor). Results of the first experiment showed that resi-dues incorporated in the top 0-30cm soil depth had significantly (P≤0.01) increased loss of dry matter weight compared to surface application. Decom-position rate constants of surface and sub-surface application were 0.029% week-1 and 0.041% week-1, respectively. Potassium was the fastest nutrient released with 50% loss attained after the 2nd and 6th week from incorporation and surface application, respectively. Nitrogen, P, Ca, and Mg releases from water hyacinth incorporated in the sub-soil were significantly (P≤ range from 0.0001 to 0.008) high compared to surface application. Nutrients loss was in the order of K =Mg > P > N > Ca. However, results of the second experi-ment showed that incorporation of water hyacinth residues significantly (P ≤ 0.001) decreased pH (by about 27%) and hydraulic conductivity (by 40-46%). Also, cation exchange capacity and organic C were significantly increased by about 23 and 100%, respectively. The study concluded that ap-plication of water hyacinth could be one of the good alternatives for improving quality of arid soils.
Afficher plus [+] Moins [-]EFFECT OF IRRIGATION INTERVALS AND INTERCROPPING PATTERNS ON YIELD AND ITS COMPONENTS OF SOYBEAN AND SUNFLOWER IN RECLAIMED LAND Texte intégral
2008
Nawar F.R.R.
Two field experiments were conducted at Nubaria Agric. Res. Station during 2003 and 2004 seasons. The objective of this investigation aimed to study the effect of irrigation intervals (irrigation every 14 and 28 days) and six intercropping patterns: (1) Pure stand of soybean (sown in hills 10 cm distance apart on each side of the ridge and thinned at two plants/hill). (2) Pure stand of sunflower (sown in hills 30 cm distance on side of the ridge and thinned at one plant/hill). (3) Soybean sown on one side of the ridge and sunflower sown on the other side of the ridge (100% soybean+100% sunflower). (4) Soybean sown in 2:2 rows with sunflower. (5) Soybean sown in 2:4 rows with sunflower. (6) Soybean sown in 4:2 rows with sunflower on yield and its components of both crops, as well as the competitive relationships. A split plot in complete randomize design with four replicates was used. The results indicated that Irrigation intervals had significant effects on soybean plant height, number of pods/plant, seed yield/fad. and seed oil percentage of soybean plants. Intercropping patterns had significant effects on all studied traits, except oil and protein content percentages in the two seasons. The highest seed yield/fad. was obtained by irrigation every 14 days and sowing soybean in pure stand. Pure stand gave higher seed yield of soybean than that of all intercropping patterns. Irrigation intervals had significant effects on sunflower plant height, number of leaves/plant, seed yield/plant and seed yield/fad. of sunflower plants in the two seasons. Also, intercropping patterns had significant effects on all studied traits in the two seasons. Pure stand of sunflower gave higher seed yield/fad. than all intercropping patterns. The highest seed yields of sunflower and soybean were obtained by irrigation every 14 days and pure stands in the two seasons. The results indicated that land equivalent ratios (LER) of soybean and sunflower values were more than one. Moreover, it could be concluded that soybean and sunflower sown at pure stands with irrigation every 14 days can be recommended for raising soybean and sunflower productivity as compared with all intercropping patterns under the condition of Nubaria region. Also, sunflower was always the dominant crop, whereas soybean was dominated.
Afficher plus [+] Moins [-]CHEMICAL COMPOSITION OF CAMEL'S COLOSTRUM AND MILK IN UNITED ARAB EMIRATES Texte intégral
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.
Afficher plus [+] Moins [-]EVALUATION OF ANTIOXIDANT ACTIVITY OF SOME SPICES AND THEIR APPLICATION IN CROISSANT AND FILLING CREAM Texte intégral
2008
Hanan M.A. Al-Sayed
Natural antioxidants have gained considerable interest in recent years for their role in preventing the auto oxidation of fats, oils and fat containing food products. In this study, six spices containing natural antioxidants were evaluated for their re-tarding fat oxidation compared to butylated hy-droxyl toluene (BHT). The yield obtained from water extract of the tested spices ranged between 20% and 50 %. Carob gave the highest yield fol-lowed by anise and cinnamon, then caraway and fennel, while ginger gave the lowest yield .The free radical scavenging activities measured by 2-diphenyl-1-picryl-hydrazyl (DPPH) were 88.08%, 81.69%, 79.62% , 78.93% , 73.06% , and 71.50 % for cinnamon, anise, carob, caraway ginger, and fennel, respectively at concentration of 2250 μg/ml. Cinnamon showed higher antioxidant ac-tivity on linoleic acid oxidation than BHT fol-lowed by anise, carob and ginger. While, fennel and caraway recorded closely antioxidant activity to that of BHT at low concentration of 100 μg/ml. Total phenolic content of the tested spices varied ranging from 11.19 to 22.95 mg as gallic acid / gm dry extract in carob and caraway, respectively. Depending upon the sensory evaluation of crois-sant containing different levels of tested spices, a concentration of 1.5% of anise, caraway fennel and cinnamon was chosen, while the chosen con-centration of ginger was 2.5% and carob was 1% for testing their effectiveness against oxidation of lipid in croissant. However, a concentration of 2% of anise, fennel, ginger and carob was chosen while, the chosen concentration of caraway and cinnamon was 1% for testing their effectiveness against oxidation of lipid in filling cream. Addi-tion of tested spices gave an excellent antioxidant effect on croissant and filling cream compared with the effect of BHT. The increase in both per-oxide and acid values after 14 and 28 days respec-tively were lower than of control and BHT. Carob, ginger, caraway and cinnamon were more effec-tive in controlling lipid oxidation during storage. In conclusion addition of tested spices as sources of effective natural antioxidants retarded lipid oxi-dation and maintain the quality of croissant and filling cream during storage.
Afficher plus [+] Moins [-]EFFECT OF VAPOR GARD AND CALCIUM CHLORIDE TREATMENTS ON KEEPING QUALITY OF NAVEL ORANGES AT DIFFERENT STORAGE TEMPERATURES Texte intégral
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.
Afficher plus [+] Moins [-]EVALUATION OF PERFORMANCE OF DAMASCUS GOAT AND ITS CROSSES WITH EGYPTIAN BALADI AND BARKI Texte intégral
2008
Khallouf N | Manal Elsayed | Mona, A. Osman
A total of 3108 records on conception rate (CR) and 2123 on litter size (LS) were used in this study. CR data represented 1600 Damascus (D) does, 201 Barki (BR) does, 229 Baladi (BL) does and 1070 crossbred does between D and each of BR and BL, while LS represented 1070 D does, 128 BR does, 145 BL does and 775 crossbred does. These records were used to study the effect of crossing and other fixed effects and to estimate heritability of these two traits in the Damascus goats. Statistical models included varying combination of the fixed effects of station, genotypes within station, year of mating, month of mating, and parity and the random effect of animal nested within station, genotype, year of mating and month of mating. Variance and covariance components for Damascus data were estimated through the Gibbs Sampling technique using a model that included the fixed effects of station, year and month of mating and parity, and the random effects of doe additive genetics and permanent environmental. CR mean in different analyses ranged from 0.39 to 0.63. Damascus, with a range of CR of 0.48 to 0.63, surpassed both local breeds (ranging from 0.33 to 0.58) and was close to the crossbreds that ranged between 0.34 and 0.68. LS mean ranged from 1.26 to 1.50 in different analyses. Baladi scored the highest in LS (1.49). Damascus ranged from 1.15 to 1.24 in different locations. LS ranged from 1.37 to 1.67 for crossbreds. For both traits there was no clear evidence of the merit of Damascus goats or their crosses over the Barki and Baladi goats. More data taken under sound herd management are needed to clarify the utility of the Damascus and its crosses. Heritability estimates+SE for CR and LT in Damascus goats were 0.03 ± 0.003 and 0.04 ± 0.003, respectively.
Afficher plus [+] Moins [-]USE OF SOME VOLATILE OILS AS ATTRACTIVE AGENTS TO INCREASE FOOD CONSUMPTION IN HONEYBEE COLONIES Texte intégral
2008
Alqarni A.S | F J Alatawi
The present work aimed to investigate the stimulating and attractive effects of five volatile oils on honey bee colonies food consumption. These oils were added to sugar syrup and pollen substitutes. The consumption of sugar syrup and percentage of dead bees in caged honeybee work-ers were determined. Multi-choice test inside the honey bee colonies was carried out to determine the food consumption rate from different pollen substitutes. Positive effect was recorded by adding Coriander oil 0.03% followed by Fennel 0.15% and Spearmint oils 0.03% while nigella oil showed a repellent effect on honey bee workers. The mor-tality percentage was very low with no significant differences between treatments. Results indicated that addition of 5% pollen grains and three volatile oils increased significantly pollen substitute’s con-sumption. The highest consumption rate was rec-orded with coriander oil 0.03%. Results obtained indicated that the consumption of diets that con-tain Coriander, Fennel, and Spearmint volatile oils was more successful than control.
Afficher plus [+] Moins [-]OPTIMIZATION OF A CULTURE MEDIUM FOR BIOMASS AND δ-ENDOTOXIN PRODUCTION BY A RECOMBINANT ESCHERICHIA COLI STRAIN Texte intégral
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.
Afficher plus [+] Moins [-]CHEMICAL AND TECHNOLOGICAL EVALUATION OF SOME SWEET POTATO VARIETIES Texte intégral
2008
El-Bastawesy Amal | Lobna A. Hareedy | Mervat M. EL-Far
This investigation was carried out to evaluate the chemical characteristics of new eight sweet potato varieties namely, CEMSA 74-228, SANTO AMARA, NC 1525 and KEMB 37 (creamy flesh) and JAPON TRESMESINO, LO 323, TAINUNG 64 and BEAUREGARD (yellow flesh ), and study their suitability for processing. The obtained re-sults reveal that SANTO AMARA and KEMB37 varieties were the best ones having the highest content of chemical constituents compared with those of the other studied creamy flesh sweet pota-to varieties. Moreover, 140 days from planting was the best harvesting time that achieved the highest chemical characteristics. All selected creamy sweet potato varieties had adequate miner-als contents especially, KEMB 37 followed by NC 1525 and CEMSA 74-228 then SANTO AMARA varieties that could be considered good sources of minerals for human nutrition. Yellow flesh sweet potatoes have been recognized as valuable sources of carbohydrates, protein, dietary fibers and could be considered as good sources of both vitamin C and total carotenoids. Moreover, TAINUNG 64 and LO 323 were found to be good sources of β-carotene (pro- vitamin A). The more suitable har-vesting time for yellow sweet potato varieties, which recorded the highest levels of essential ele-ments, was 140 days from planting. On the other hand, TAINUNG 64 variety could be considered the best one compared to the other examined vari-ties. The most suitable varieties that having good quality attributes for processing were SANTO AMARA and KEMB 37 as creamy flesh and TAINUNG 64 and BEAUREGARD as yellow flesh sweet potato varieties. Moreover, these va-rieties could be successfully used in the produc-tion of new and untraditional sweet potato prod-ucts.
Afficher plus [+] Moins [-]USE OF ESSENTIAL OILS FOR CONTROLLING BACTERIAL ANGULAR LEAF SPOT DISEASE OF CUCUMBER Texte intégral
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.
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