خيارات البحث
النتائج 721 - 730 من 1,442
Improvement of canola seed yield and quality using sulphur and irrigation intervals under different irrigation water salinity levels
2010
Al-Solimani, S.G. | El-Nakhlawy, F.S. | Al-Morshdy, M.H.
This investigation was conducted at Hada Elsham Experimental Research Station, King AbdulAziz University during 2007/2008 and 2008/2009 seasons, to study the effects of two irrigation water salinity levels (1200 mg/L and 10000 mg/L), three irrigation water intervals (3, 6 and 9 days) and three sulphur fertilizer rates (0.0, 4.0 and 6.0 t/ha) on seed yield; yield components and seed quality of canola, Pactole cv. The obtained results showed that seed yield kg/ha was significantly increased (Received June 1, 2009) (Accepted June 27, 2009) under the 1200mg/L irrigation water and 6t/ha of sulphur more than the seed yield/ha under the effect of 1200 mg/L irrigation water with 4 t/ha sulphur or 10,000 mg/L irrigation water with 6t/ha sulphur with no significant differences between the two later treatments. Irrigation every 3 days significantly dominated over the irrigation every 6 or 9 days on seed yield and yield components. Irrigation with 10.000 mg/L salinity water significantly decreased No. of branches /plant, No. of fruit/plant and seed weight/ plant. Besides, Protein content of the seed as well as oil content increased as water salinity increased in both seasons. As sulphur fertilizer rate increased seed yield, yield components protein and oil contents of seed significantly increased, in the two studied seasons.
اظهر المزيد [+] اقل [-]EFFECT OF POLLUTION WITH PETROLEUM ON SOME SOIL CHARACTERISTICS AND PLANT GROWTH
2009
Heba A.M. Abou-Zeid | A.E. El-Leboudi | M.A. Mostafa | E.M . Abd- Elmoniem | U.A El-Behairy
Petroleum products are complex mixtures of hundreds of hydrocarbon compounds. Petroleum has been recognized as a potential environmental contaminant. This research was undertaken to evaluate the effect of petroleum hydrocarbon on soil characteristics and seeds germination in arid lands. Results indicated that bulk density and real density of the polluted samples are relatively higher and lower respectively then the corresponding values of the unpolluted soils. Percent ages of the clay fraction obtained with and without removing the cementing agents showed high and low values for % clay fraction respectively. Low calcium carbonate content was found in the polluted samples as a result of solubilization effects of the petroleum products on calcium carbonate particles. ECe values were very high in the polluted samples (ECe = 28.6 - 82.5 dS/m) and very low in the unpolluted samples (ECe = 2.75 - 2.79 dS/m). Soluble calcium and sulphat ions were the dominant ions in the saturation extract of unpolluted soil samples. Organic matter contents were high (4.94%) in the polluted soil and Low in the unpolluted soil (0.54%). Soil polluted with hydrocarbon was very high (7.13-7.5%) in the unpolluted soil and very low (0.63-0.71%) in the polluted soil. Total elemental contents shows that the most important metals with regard to potential hazards in the contaminated soils, are Cr, Pb, and Ni. Other heavy metals indicated low to medium concentration either in petroleum polluted or the non polluted soils. The concentration of toxic elements in the tested soils could be derived from petroleum pollution and/or from it's chemical weathering particularly under the relatively low pH of the polluted soils. Results indicated no barley seed emergence after 14 days in the polluted soil even after several leaching to alleviate the high level of salt concentrations in the polluted soil. The data reflect the serious effects of petroleum products on the deterioration of soil characteristics which reflected on the emergence of barley seeds.
اظهر المزيد [+] اقل [-]MULTIVARITE 0F RELATING YIELD COMPONENTS IN A SET OF CORN GENOTYPES
2009
Zienab Nassar, M.
This work was conducted at the Experimental Farm of Nasser's Faculty of Agricultural Sciences in Lahej Governorate, Yemen, during three seasons 2003, 2004 and 2005. Five statistical procedures of relating yield components to yield; i.e., simple correlation coefficient, the path coefficient analysis, the stepwise regression, the multiple regressions and factor analysis were applied to seven yield contributing characters to determine their functional relationships to yield. Sixteen Maize genotypes were used in this study. Simple correlation coefficient revealed that, number of leaves/plant, ear height, ear length, number of rows/ear, number of kernels/row, 1000-kernel weight and shelling% had the greatest influence on grain yield/h. According to path analysis, weight of 1000-kernel had the greatest direct effect (22.23%) towards grain yield/h. While, number of kernels/row (9.33%) and ear length (9.32%) had the highest indirect effect to grain yield. Multiple linear regressions indicated that the variables which had the highest partial coefficient of determination in seed yield/h, were ear height, ear length, number of rows/ear and 1000-kernel weight (R2 = 43%, 22%, 9% and 12%, respectively). The stepwise regression shows that, 1000-kernel weight, number of kernels/row, number of rows/ear and shelling% were accepted variables which had the highest coefficients of determination with seed yield (88.9%). The factor analysis grouped 7 yield contributing characters in two factors, which altogether were responsible for 70.42% of the total variability in the dependence structure.
اظهر المزيد [+] اقل [-]PRODUCTIVITY AND NUTRITIVE VALUE OF NATURAL VEGETATION AT WADI-WATEER REGION IN SINAI
2009
The present study was carried out in 2004/ 2005 – 2005/2006 seasons to make survey of plant vegetation at Wadi Wateer (East southern of Sinai) (a bout 100 km length) at 9 successive sites. The study was carried through two years (two wet and dry seasons) to evaluate the vegetation structure throughout 20 chart quadrates (2 m x 2 m) at each site. The results showed that most of the pasture measurements such as plant density (plants / 4 m2), coverage %, frequency %, abundance % and fresh, and dry yields (ton/fad.) reached its maximum values during the wet seasons. Sites 5, 6, 7, 8 and 9 were more suitable for growth of the plant associations than other sites under studies. Many plant species such as Astragalus spinsous, Medicago laciniata, Artemisia Judica, Artemisia monosperma, Legum spartum, Haloxylon salicornicum, Calotropis procera, Lycium shawii and Paronychia sinaica were capable to grow under the aridity conditions at Wadi Wateer area.
اظهر المزيد [+] اقل [-]EFFICACY OF CHEMICAL AND BIOLOGICAL TREATMENTS FOR CONTROLLING SOIL-BORNE PATHOGENS OF SOYBEAN
2009
Ahmed Awad Altalb
Several soil-borne fungal pathogens attack soybean plants, causing seedling damping-off and root rot diseases, in Egypt. Isolation trials from rooted rots of soybean, collected from various locations at Gharbiya, Kafr El-Sheikh and Minufiya governorates, revealed that Rhizoctonia solani, Fusarium solani and Macrophomina phaseolina were the most virulent and predominant pathogens. All the tested fungicides significantly reduced linear growth of the tested pathogens. Three known bioagents i.e. Trichoderma harzianum, T. hamatum and Bacillus subtilis were tested against such pathogens, and revealed remarkable effect in reducing mycelial growth on PDA medium. T. hamatum, mainly, grew over the mycelium of the tested pathogens. Under greenhouse conditions, both the fungicides and antagonists gave significant reductions of root rot severity, but fungicides were more effective than biocontrol agents in reducing the disease. Application of the selective antagonists and fungicides significantly decreased soybean root rot than untreated check, in naturally pathogen- infested fields. Plant growth and activity of nitrogenase enzyme were enhanced greatly, when the fungicides were applied compared with antagonists treatments.
اظهر المزيد [+] اقل [-]UTILIZATION OF CAROB PODS IN THE PRODUCTION OF ALTERNATIVE TO COCOA POWDER
2009
Roasting process of carob pods at various temperatures for different times was carried out to study the effect of its process on the chemical constituents, minerals content, phenolic compounds and antioxidant activity. Volatile compounds were also determined for roasted carob powders. The obtained results revealed that the protein content was 5.42% (on dry weight basis), which decreased with increasing the processing temperatures. Whereas, ash increased gradually by increasing the roasted temperatures but lipids was decreased. The predominant mineral in carob powders was calcium followed by sodium, potassium and magnesium, respectively whereas; the raw carob pods contain 21.07mg/g of total phenolic compounds. Roasting treatment caused to the degradation of phenolic compounds which increased with increasing the roasting temperatures. The antioxidant activity of the carob powders was determined by 2,2-diphenyl-1-picryl-hydrazyl (DPPH) as free radical scavenging. However, the activity of antioxidant was decreased owing to the roasting process. On the other hand, sensory characteristics for both hot drinks and prepared cakes showed greater preference, especially for samples contained roasted carob powders at 160˚C for 30 min. and/or 40min. compared with that in tested samples and control. Seven aroma compounds were positively identified by using GC–mass spectrometry. The major aroma compounds of carob powders were 3-methyl butanal and methyl propanal which was found in chocolate and it's responsible for chocolate flavor. Moreover, other volatile compounds were identified in roasted carob powders and which also found in dark chocolate such as 2-Heptanone, Pentan-2-ol and Linalool. Also, Nonane-2-one and Hexanal were found and identified in roasted carob powders.
اظهر المزيد [+] اقل [-]PROTOPLAST FUSION IN PENICILLIUM FUNICULOSUM MUTANTS FOR ENHANCING DEXTRANASE PRODUCTION
2009
ABSTRACT Two induced mutant strains, obtained from the fungus Penicillium funiculosum after UV treatments, were used for protoplast fusion. These mutants (12 and 18) were selected according to their dextranase activity and stability. Seven fusants having dextranase over-yield than their parental strain were obtained. The best dextranase producing fusant (No. 2) was selected for further studies. Dextranase was purified from cell-free culture of fusant 2 by consecutive column chromatography using Q-sepharose FF, Superose 12 prep. grade 60/600 and Mono Q-FPLC. The purification was estimated by SDS-PAGE as well as isoelectric focusing. Four dextranase components (I, II, III and IV) were separated with an estimated molecular weights of 67 kDa. The pI of the all components were found to be around 3.0 as estimated by gel electrophoresis using both broad and low pI calibration protein kits. The dxetranase components showed pH and optimum temperature of 5 and 55oC, respectively. Dextran was the sole carbon source for dextranase production by the dextranase components. The effect of the dextranase components on different types of dextrans were also studied.
اظهر المزيد [+] اقل [-]INCORPORATION OF BARLEY WHOLE MEAL IN SOME DAIRY AND FOOD PRODUCTS
2009
The effect of incorporation of barley whole meal (BWM) whether in ice milk (IM) as skim milk powder (SMP) substitute, in tomato soup (ST) as modified starch substitute and in Egyptian kishk (EK) as wheat flour substitute on their properties was studied. The obtained results reveal that, the substitution with BWM was associated with increases in the fiber, β-glucan, K and Mg contents in all products studied. Whereas, the protein and ash contents increased in ST samples. The freezing point of IM mixes heightened and the specific gravity lowered by BWM addition instead of SMP. In spite of the stabilizer (CMC) level, the overrun % decreased by substitution of SMP with BWM but the melting resistance increased. Rheologically, the 50% replacement SMP with BWM achieved remarkable increase in the rheological response of IM samples especially in the presence of 0.1% CMC. At the same time, the replacing of modified starch by 200% of BWM in ST samples resulted in increasing the shear stress value and led to a mix behavior of thixotropy and rheopectic in ST samples. Although the partial or fully replacement of wheat flour with BWM led to reduction in the thixotropy area in EK samples. Organoleptically, IM and EK with 50% BWM and ST with 200% BWM substituted gained the highest sensory scores especially in the absence of CMC in IM samples.
اظهر المزيد [+] اقل [-]ISOLATION AND IDENTIFICATION OF AN ACARICIDAL GLYCOSIDE FROM Acacia saligna LEAVES
2009
A.M Moussa | A.M Emam | M.A. Mohamed | A.E Mohamed
as sources of biologically active secondary metabolites including pesticides because of their eco-friendly nature. The present study indicated that the ethylacetate extract of the Acacia saligna leaves exhibited acaricidal activity against the phytophagous twospotted spider mite ( Tetranychus Urticae Koch ). The chromatographic separation methods led to isolation of a pure compound from Acacia saligna leaf ethylacetate extract which exerted acaricidal action against the tested mite with LC50 value of 74.13 mg.l-1 after 48 h. Based on chemical (acid hydrolysis) and spectroscopic (1H, C13- NMR and MS) methods, the isolated compound was identified for the first time from plants as 2-hydroxymethyl-9-hydroxy-9-methyl-undecanyl (O-α-L-arabinopyranosyl-β-D-galactopyranoside.
اظهر المزيد [+] اقل [-]RELATIVE IMPORTANCE OF FIBER PROPERTIES AFFECTING YARN HAIRINESS IN SOME EGYPTIAN COTTON VARIETIES
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
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