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51.
Mrabet A Ferchichi A Chaira N Mohamed BS Baaziz Z Penny TM 《Pakistan journal of biological sciences: PJBS》2008,11(7):1003-1008
The date palm, Phoenix dactylifera, is a palm extensively cultivated for its edible fruit. The chemical composition and the water content of ten Tunisian date varieties were determined. For all analysis, the Deglet Nour variety was taken as reference. Compositional analysis showed that the littoral varieties were very rich in reducing sugars (26 to 51%) than Deglet Nour which was rich in sucrose (54%). The relative results of the moisture content showed that the littoral varieties were classified as soft dates. The vitamin C analysis showed that the littoral varieties were very rich in this compound (24 to 46 mg/100 g) than Deglet Nour (1.12 mg/100 g). The mineral analysis showed that the littoral dates were relatively rich in potassium (283 to 733 mg/100 g) and presented a weak content in sodium (0.06 to 0.09 mg/100 g). 相似文献
52.
Shonouda M Osman S Salama O Ayoub A 《Pakistan journal of biological sciences: PJBS》2008,11(4):546-552
The leaf extract and its fractions of Peganum harmala L. have shown pronounced mortal effect, decreased percent pupation and adult emergence of the cotton leaf worm, Spodoptera littoralis Boisd. The third instar larvae fed for two days on treated leaves were more susceptible to plant extract and its ethyl acetate and chloroform fractions. The active lowest concentration (5%) of the leaf fractions of P. harmala showed significant effect on the percentage of emerged adult parasitoids, Microplitis rufiventris Kok. GC/MS analysis showed the major constituent in ethyl acetate fraction was (23S) ethylcholest-5-en-3 beta-ol (28.04%) while those of chloroform fraction were hydroxyfuranocoumarin (Bergaptol) (15.68%), piperidinone (12.08%), thymol (11.82%), phosphoric acid, tributyl ester (9.80%) and trimethyl-nonenol (9.66%). The medicinal plant P. harmala could be carefully applied in integrated pest management due to its strong effect on cotton leaf worm pest. 相似文献
53.
Yousef Alhaj Hamoud Hiba Shaghaleh Wang Ruke Willy Franz Gouertoumbo Amar Ali Adam hamad Mohamed Salah Sheteiwy Wang Zhenchang Guo Xiangping 《水稻科学》2022,29(5):473-488
Wheat straw burial has great potential to sustain rice production under alternate wetting and drying (AWD) irrigation. A field experiment was conducted with three wheat straw burial treatments, including without straw burial (NSB), with light straw burial of 300 kg/hm2 (LSB) and dense straw burial of 800 kg/hm2 (DSB), as well as three AWD regimes: alternate wetting/moderate drying (AWMD), alternate wetting/severe drying (AWSD) and alternate wetting/critical drying (AWCD). The rice growth and grain quality were higher in LSB and NSB than those in NSB under the same AWD regime. The AWMD × DSB treatment resulted in the highest yield, brown rice rate, milled rice rate, amylose content and protein content. Conversely, the AWCD × NSB treatment led to the lowest yield, brown rice rate, milled rice rate, amylose content and protein content. The active absorption area and nitrate reductase activity of roots were higher in the AWMD × DSB treatment than those in the AWCD × NSB treatment, as the former increased organic carbon and nitrogen contents in the rhizosphere, whereas the latter reduced their availability. Total soluble protein content and glutamine synthetase activity were greater in the AWMD × DSB treatment than those in the AWCD × NSB treatment. The activities of superoxide dismutase and catalase were higher in the AWMD × DSB treatment compared with the AWCD × NSB treatment, leading to the amelioration of oxidative cell injury, as shown by a lower malonaldehyde level. This study suggested that farmers should implement AWMD irrigation after leaving the straw residues in the field, followed by deep tillage to improve soil quality and mitigate the drought stress cycles of AWD. This approach can improve rice growth and grain quality and alleviate the problems of disposal of straw residues and water scarcity for sustainable rice production. 相似文献
54.
A field experiment on an alluvial clay loam soil at Giza revealed that the dry matter yield, as well as N and P uptake of Ammi visnaga fruits or herb were significantly increased with nitrogen application up to 60 kg N/ha. P application up to 30 kg P205/ha significantly increased the dry matter yield and the uptake of N and P of herb, but did not significantly affect those of fruits. At maturity, most, if not all, chromones rest in the fruits. The concentration in herb (Stems + rays) did not exceed 0.01 %. Higher yields of total chomones, khelling and visnagin in fruits were brought about with nitrogen application at the rate of 60 kg N/ha. P application tends to increase all these parameter, yet all were nonsignificant. The interacting effect between nitrogen and phosphorus on these characters was insignificant. Plant analysis of leaves, stem, or shoot at 120, 135 and 150 days old plants revealed no relation between phosphorus concentration and final yield. However, nitrogen concentrations provided a good tool to evaluate the nutritional status of the plants. The critical level was 2.75, 1.85, or 1.45 % N in shoots of 120, 135, or 150 days old plants. The P % in these shoots was around 0.35–0.50 %. 相似文献
55.
H. Moawad M. H. Enany S. M. S. Badr El-Din S. A. Z. Mahmoud Rawia F. Gamal 《植物养料与土壤学杂志》1984,147(6):785-792
The application of urea phosphate, urea nitrate and thoiurea to a silty clay soil from Nile Delta (pH 7.4, 1,9% CaCO3) inhibited soil urease activity if compared to urea. The nitrification process of ammonia formed from urea hydrolysis was retarded. The use of these urea derivatives eliminated nitrite accumulation and greatly retarded nitrate formation with increased recovery of urea-N throughout the experimental period. Gaseous losses of urea-N as ammonia or by denitrification were reduced. These derivatives may be much more advantageous than urea if fertilizer effeciency is to be increased. 相似文献
56.
Salah E. M. Hamam Mohamed F. Hamoda Habib I. Shaban Amal S. Kilani 《Water, air, and soil pollution》1988,37(1-2):55-64
The solubilities and diffusion coefficients of crude oils having API° ranging from 11 to 28 have been measured in distilled and saline water of 44 g L?1 NaCl at temperatures 25, 35, and 45 °C. A linear relationship was observed between the maximum oil solubilities in distilled water and those in saline water for all the crudes over the range of temperature studied. The Setschenow salting-out parameter was found to be 0.125 independent of temperature and API°. Such a parameter is valuable in estimating the crude oil solubilities in waters of different salinity. An analytical solution for unsteady-state diffusion was done using Fourier series. A linear relationship was found between the diffusion coefficients of oils in distilled water and those in saline water. Observed data for diffusion coefficients of the oils have been correlated in terms of API°, temperature and ionic strength with an average absolute deviation of 2%. 相似文献
57.
Bah CS Fang EF Ng TB Mros S McConnell M Bekhit Ael-D 《Journal of agricultural and food chemistry》2011,59(10):5720-5728
In this study, a rhamnose-binding lectin from the roe of chinook salmon (Oncorhynchus tshawytscha) was purified and characterized, and its biological activities were examined in several model systems. Chinook salmon roe lectin had a molecular mass of 30 kDa and agglutinated rabbit and bovine erythrocytes. The hemagglutination activity of the lectin was not affected by metal ions. The lectin was stable up to 70 °C and between pH 4 and pH 11. Chinook salmon roe lectin did not exert antifungal activity toward the fungal species tested and did not exhibit mitogenic response toward mouse splenocytes up to a concentration of 5 mg/mL. The lectin had selective antiproliferative activity toward human breast cancer MCF-7 cells and hepatoma Hep G2 cells. It also induced the production of nitric oxide from mouse peritoneal macrophages. This is the first report that demonstrates these biological activities from chinook salmon roe lectin. 相似文献
58.
Olfa Shaiek Denis Loustau Pierre Trichet Céline Meredieu Beya Bachtobji Salah Garchi Mohamed Hédi EL Aouni 《Annals of Forest Science》2011,68(3):443-452
• Introduction
In order to predict the biomass of aerial components of maritime pine stands (Pinus pinaster Ait.), generalized allometric equations were developed using data collected from the southern and northern margins of its geographical area. 相似文献59.
Potent bacterial strains effective against the whitefly, Bemisia tabaci, nymphs (second instar), were isolated from tomato cultivated fields at Fayoum governorate, Giza, Egypt. Of 72 isolates, 12 with the most morphologically distinct-looking bacterial colonies were selected and named A1, A2, A3, A6, A7, A9, A12, A13, A107, B37, B45 and B100. All isolates were preliminarily identified as members of the genus Bacillus based on morphological, physiological and biochemical characteristics. When tested for their pathogenicity against Bemisia tabaci, the 12 isolates revealed varying efficiencies with isolates A1 and A9 being superior, exhibiting maximum mortality of 92.2 and 90.8% on day 10, respectively. Isolate A7 recorded the lowest percentage at 18.3%. Further genetic characterization of the 12 isolates was performed using inter simple sequence repeat (ISSR), randomly amplified polymorphic DNA (RAPD) and 16S rDNA gene sequencing analysis. RAPD and ISSR results confirmed each other. The combined ISSR and RAPD phylogenetic tree showed two major clusters. With 16S rRNA gene analysis, isolate A1 and A12 sequences recorded 100% identity with Bacillus thuringiensis, while isolates A7 and B100 showed 95.7% and 95.6% identity with Bacillus cereus and Bacillus sphaericus, respectively. 相似文献
60.
P. M. Verbost M. A. Salah El-Deen P. Pelt M. M. J. C. Bijvelds S. E. Wendelaar Bonga 《Fish physiology and biochemistry》1996,15(4):299-305
An intracellular ATP-dependent Ca2+ pumping mechanism, distinct from mitochondrial Ca2+ accumulation, was identified within tilapia gill cells. Cell suspensions treated with 0.003% saponin, which selectively permeabilizes the plasma membrane, were used to characterize the Ca2+ sequentering mechanisms as endoplasmic reticulum and mitochondria and to determine the effect of Zn2+ on their Ca2+ storing activity. Of the Ca2+ taken up by the endoplasmic reticulum, 80% was released by IP3 (10 mol l–1). The Ca2+ pump of the endoplasmic reticulum was 2.5 times less sensitive to Zn2+ (IC50=0.05 nmol l–1) than was the mitochondrial uptake mechanism (IC50=0.20 nmol l–1). The results indicate that Ca2+ is stored predominantly within the endoplasmic reticulum at 0.1 mol l–1 and that this storing capacity is seriously attenuated by namomolar concentrations Zn2+. 相似文献