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91.
Among the most important Mediterranean annual crops durum wheat is widely grown in drought-prone areas. Therefore improving water-use efficiency 《分子植物育种》2007,5(2):223-223
Among the most important Mediterranean annual crops, durum wheat is widely grown in drought-prone areas. Therefore, improving water-use efficiency (WUE) of durum wheat represents a major breeding goal. IDu-WUE (Improving Durum wheat for Water Use Efficiency and yield stability through physiological and molecular approaches) is a collaborative project among public and private research centres in Italy, Spain and WANA (West Asia and North Africa) countries (Morocco, Tunisia, Syria and Lebanon) funded by the European Union aimed at investigating the genetic variation for WUE and yield stability in durum wheat grown in Mediterranean droughtprone areas. During the first year of the project, a number of morpho-physiological traits (e.g. early vigour, flowering time, leaf rolling, number of fertile tillers, etc.), WUE, WUE-related traits (e.g. carbon isotope discrimination, canopy temperature, chlorophyll fluorescence, etc.), yield and its components have been investigated in a RIL population (249 lines) and a collection of ca. 190 durum wheat accessions characterized by a high level of linkage disequilibrium (Maccaferri et al., 2005), 相似文献
92.
Karioti A Skaltsa H Demetzos C Perdetzoglou D Economakis CD Salem AB 《Journal of agricultural and food chemistry》2003,51(22):6505-6508
Essential oils from hydroponically cultivated Salvia fruticosa were analyzed by GC-MS techniques. Three different levels of nitrogen (100, 150, and 200 mg/L) were used in the nutrient solution for the cultivation, using the nutrient film technique. A total of 79 compounds were identified, and qualitative and quantitative differences have been observed between the samples collected at full bloom (flowering stage) and at the end of the seed formation stage. 1,8-Cineole, beta-caryophyllene, and viridiflorol were the predominant constituents in most cases. 13-epi-Manool was identified by using GC parameters and mass spectrum fragmentation pattern, whereas labd-7,13-dien-15-ol, a labdane type diterpene, was identified for the first time in the genus Salvia, using GC parameters and an authentic sample. The results obtained from GC-MS analyses were submitted to chemometric analysis. 相似文献
93.
94.
Fatma Basyoni Salem 《Water, air, and soil pollution》1991,60(1-2):27-33
The proposed method is used for determination of trace amounts of phosphate in water samples especially of Dakahlia Governorate. The recommended procedure is based on the formation of molydophosphoric acid which upon, selective reduction with the reducing agent oxalyldihydrazide produces a blue color due to the molybdenum blue. The intensity of the blue color is proportional to the amount of phosphate initially incorporated in the heteropoly acid. The resulting blue complex could be determined in the range of 2.25 to 22.46 μg P with molar absorptivity of 33418 L?1 mol?1 cm?1 at 880 nm. The reduction of phosphomolybdate complex by oxalyldihydrazide is chosen in the work and the result is compared with those obtained with the reducing agent potassium antimonyl tartrate, the reduction methods are frequently recommended for manual analysis of waters and wastes for P. 相似文献
95.
Mohamed A. Tarawally Hanoi Medina M. E. Frmeta C. Alberto Itza 《Soil & Tillage Research》2004,76(2):95-103
The level of compaction induced on cultivated fields through trafficking is strongly influenced by the prevailing soil-water status and, depending on the attendant soil degradation, vital soil hydraulic processes could be affected. Therefore, understanding the relationship between field soil-water status and the corresponding level of induced compaction for a given load is considered an imperative step toward a better control of the occurrence of traffic-induced field soil compaction. Pore size distribution, a fundamental and highly degradable soil property, was measured in a Rhodic Ferralsol, the most productive and extensively distributed soil in Western Cuba, to study the effects of three levels of soil compaction on soil water characteristic parameters. Soil bulk density and cone penetration index were used to measure compaction levels established by seven passes of a 10 Mg tractor at three soil-water statuses corresponding to the plastic (Fs), friable (Fc) and relatively dry soil (Ds) consistency states. Pore size distribution calculated from soil water characteristic curves was classified into three pore size categories on the basis of their hydraulic functioning: >50 μm (f>50 μm), 50–0.5 μm (f50–0.5 μm) and <0.5 μm (f<0.5 μm). The greatest compaction levels were attained in the Fs and Fc soil water treatments, and a significant contribution to compaction was attributed to the existing soil water states under which the soil compaction was accomplished. Average cone index (CI) values in the range of 2.93–3.70 MPa reflected the accumulation of f<0.5 μm pores, and incurred severe reductions in the volume of f>50 μm pores in the Fs and Fc treatments, while an average CI value of 1.69 MPa indicated increments in the volume of f50–0.5 μm in the Ds treatment. Despite the differential effects of soil compaction on the distribution of the different pore size categories, soil total porosity (fTotal) was not effective in reflecting treatment effects. Soil water desorption at the soil water potentials evaluated (0.0 to −15,000 cm H2O) was adversely affected in the f<0.5 μm dominated treatments; strong soil water retention was observed with the predominance of f<0.5 μm, as was confirmed by the high water content at plant wilting point. Based on these findings, the use of field capacity water content as the upper limit of plant available soil water was therefore considered inappropriate for compacted soils. 相似文献
96.
Abdelwahab SI Hassan LE Sirat HM Yagi SM Koko WS Mohan S Taha MM Ahmad S Chuen CS Narrima P Rais MM Hadi AH 《Fitoterapia》2011,82(8):1190-1197
The in vivo and in vitro mechanistic anti-inflammatory actions of cucurbitacin E (CE) (Citrullus lanatus var. citroides) were examined. The results showed that LPS/INF-γ increased NO production in RAW264.7 macrophages, whereas L-NAME and CE curtailed it. CE did not reveal any cytotoxicity on RAW264.7 and WRL-68 cells. CE inhibited both COX enzymes with more selectivity toward COX-2. Intraperitoneal injection of CE significantly suppressed carrageenan-induced rat's paw edema. ORAC and FRAP assays showed that CE is not a potent ROS scavenger. It could be concluded that CE is potentially useful in treating inflammation through the inhibition of COX and RNS but not ROS. 相似文献
97.
Anti-uveal melanoma activity-guided fractionation of the MeOH extract of Acacia nilotica pods resulted in the isolation of the new compound gallocatechin 5-O-gallate (5) in addition to methyl gallate (1), gallic acid (2), catechin (3), catechin 5-O-gallate (4), 1-O-galloyl-β-D-glucose (6), 1,6-di-O-galloyl-β-D-glucose (7) and digallic acid (8). The structures of the isolated compounds were elucidated on the basis of HRESIMS, NMR spectroscopy and CD data. In addition to uveal melanoma, the antiproliferative activities of the isolated compounds and the related compound epigallocatechin 3-O-gallate (EGCG) were evaluated against cutaneous melanoma, ovarian cancer, glioblastoma and normal retinal pigmented cells. 相似文献
98.
Maruyama N Mohamed Salleh MR Takahashi K Yagasaki K Goto H Hontani N Nakagawa S Utsumi S 《Journal of agricultural and food chemistry》2002,50(15):4323-4326
We purified four single molecular species of beta-conglycinin heterotrimers consisting of the alpha and beta subunits or the alpha' and beta subunits from mutant soybean cultivars lacking the alpha or alpha' subunit, respectively, and examined their structural features and physicochemical functions. The extent of the hydrophobicities of the heterotrimers was related to the number of the alpha or alpha' subunit. The thermal stabilities of the heterotrimers were mainly conferred by the subunit which had lower thermal stability. Solubilities at low ionic strength (mu = 0.08) of the heterotrimers containing the alpha or alpha' subunit were very similar to those of the alpha and alpha' homotrimers, respectively. Emulsifying abilities and heat-induced associations of the heterotrimers containing one beta subunit were similar to those of the alpha or alpha' homotrimer, whereas those of the heterotrimers containing two beta subunits were similar to those of the beta homotrimer. 相似文献
99.
The effects of wheat straw and different forms of N on denitrification and N immobilization were studied in an anaerobic water-sediment system. The water-sediment system was supplemented with various combinations of wheat straw and 15N-labelled and unlabelled (NH4)2SO4 or KNO3, and incubated anaerobically at 30°C for 10 days. 15N-labelled and unlabelled NO
inf3
sup-
, NO
inf2
sup-
, NH
inf4
sup+
, and organic N were determined in the water-sediment system. The gases evolved (N2, CO2, N2O, and CH4) were analyzed by gas chromatography at regular intervals. Larger quantities of 15N2–N and organic 15N were formed in wheat straw-amended systems than in non-amended systems. Trends in CO2 production were similar to those of N2–N evolution. The evolution of N2O and CH4 was negligible. Denitrification processes accounted for about 22 and 71% of the added 15NO
inf3
sup-
–N in the absence and presence of wheat straw, respectively. The corresponding denitrification rates were 3.4 and 12.4 g 15Ng-1 dry sediment day-1. In systems amended with 15NO
inf3
sup-
–N and 15NO
inf3
sup-
+NH
inf4
sup+
–N without wheat straw, 1.82 and 1.58%, respectively, of the added 15NH
inf3
sup-
–N was immobilized. The corresponding figures for the same systems supplemented with wheat straw were 5.08 and 4.10%, respectively. Immobilization of 15NO
inf4
sup+
–N was higher than that of 15NO
inf3
sup-
–N. The presence of NO
inf3
sup-
–N did not stimulate NH
inf4
sup+
–N immobilization. 相似文献
100.
Mohamed R. Lasheen Salwa A. Shehata Gamila H. Ali 《Water, air, and soil pollution》1990,50(1-2):19-30
The Algal Assay Procedure Bottle Test was used to investigate the effect of Cd, Cu, and Cr (VI) on the growth of Nile water algae. The results of this investigation indicated that Cd has slight inhibitory effects on algal growth at low concentration (0.05 mg L?1), while it was inhibiting algal growth at higher concentration (> 1.0 mg L?1). In contrast, Cu and Cr did not affect algal growth in all investigated concentrations. Combinations of Cd with Cu and Cr seemed to interact synergistically. The synergism between Cd and Cu was more pronounced than between Cd and Cr. Clear changes in the diversity and redundancy of algal structure took place after metal addition. The inhibitory effect of the studied metals was in the following order: Cd-Cu > Cd - Cr > Cd > Cu > Cr. 相似文献