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111.
In vitro plantlets or microtubers (in vitro produced tubers) of ‘Spunta’ potato (Solanum tuberosum L.) were planted in a 3 soil: 2 peat moss: 1 sand substrate (by volume) amended with municipal solid waste (MS W) compost at 0, 10, 20, or 30 g 4‐1 L pot. Three months later, plant growth and tuber yield were evaluated and concentrations of shoot and tuber tin (Sn), arsenic (As), copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), manganese (Mn), cadmium (Cd), and iron (Fe) were determined. Amending with MSW resulted in significant increases in concentrations of all tested metals in the substrate. Number of proliferated shoots of plants started from rooted plantlets was greatest at 10 g pot‐1 MSW, whereas shoot weight of plants started from microtubers was greatest at 10 and 20 g pot‐1 MSW. Tuber yield of plants started from rooted plantlets or microtubers was greatest at 10 or 30 g pot‐1 MSW, respectively. In all instances, amending with MSW at 30 g pot‐1 resulted in significant increases in concentrations of all tested metals in shoots and tubers. Concentrations of shoot Ni and tuber Zn and Fe for plants started from rooted plantlets and concentrations of shoot Fe and tuber As, Cu and Pb for plants started from microtubers increased consistently with increasing MSW percentage of the substrate. Plants started from rooted plantlets produced shoots with sufficient Zn, Mn, and Ni concentrations regardless of the substrate but with toxic Cu content at 30 g pot‐1 MSW. Plants started from microtubers produced shoots with sufficient Mn and Ni concentrations regardless of the substrate but with low Zn and deficient Cu in unamended substrates. All plants had shoot Fe content higher than the sufficiency range. Although there were significant differences in concentrations of some nutrients among MSW treatments, no symptoms of nutrient toxicity or deficiency were observed. In all instances, tested elements did not accumulate in tubers to levels hazardous to human health. Concentrations of Cd, the most hazardous element, in potato tubers was not high enough to pose a threat to human. Our results indicate that there is a potential use of MSW in satisfying the needs of potato growth with negligible increases in heavy metal concentrations in tubers.  相似文献   
112.
European Journal of Plant Pathology - The current research aims to evaluate the susceptibility of the tomato of the tomato (Solanum lycopersicum) cultivars 65,015 (CV1), Basma (CV2), Dalia (CV3),...  相似文献   
113.
Silver nanoparticles imbedded in polyacrylonitrile (PAN) nanofibers and converted into carbon nanofibers by calcination was obtained in a simple three-step process. The first step involves conversion of silver ions to metallic silver nanoparticles, through reduction of silver nitrate with dilute solution of PAN. The second step involves electrospinning of viscous PAN solution containing silver nanoparticles, thus obtaining PAN nanofibers containing silver nanoparticles. The third step was converting PAN/Ag composites into carbon nanofibers containing silver nanoparticles. Scanning electron microscopy (SEM) revealed that the diameter of the nanofibers ranged between 200 and 800 nm. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) showed silver nanoparticles dispersed on the surface of the carbon nanofibers. The obtained fiber was fully characterized by measuring and comparing the FTIR spectra and thermogravimetric analysis (TGA) diagrams of PAN nanofiber with and without imbedded silver nanoparticles, in order to show the effect of silver nanoparticles on the electrospun fiber properties. The obtained carbon/Ag composites were tested as gram-class-independent antibacterial agent. The electrosorption of different salt solutions with the fabricated carbon/Ag composite film electrodes was studied.  相似文献   
114.
Physical and sensory characteristics of cakes prepared with either the carbohydrate-based fat replacers N-Flate, Paselli MD 10 and Litesse (0, 25, 50 and 75% of fat weight) or fat replacers plus emulsifier (mono- and diglycerides; 0 and 3% of flour weight) were studied. Specific gravity of the batter was significantly (p 0.05) improved by using the carbohydrate-based fat replacers, especially at the 25 and 50% replacement levels. The combination of the emulsifier with either Paselli MD 10 or Litesse also enhanced the specific gravity. Cakes prepared with fat replacers at the 25 and 50% levels had higher volumes, specific volume and standing heights than those of the control. Cakes prepared with fat replacers at the 25, 50 and 75% levels were more compressible than the control. Cakes prepared with Paselli MD 10 had the highest volumes, specific volume, standing heights and compressibilities. Incorporation of emulsifier with fat replacers improved cake volumes, standing heights and compressibilities. Cakes prepared with fat replacers exhibited higher crust and crumb color values compared to the control. Cakes prepared with 25 or 50% fat replacers had higher mean scores for flavor, softness and eating quality than the control. Incorporation of emulsifier with fat replacers did not affect the crust color, crumb color and flavor, but significantly (p 0.05) improved softness and eating quality.  相似文献   
115.
Four high yielding imported and one local peanut cultivar, grown under local soil and climatic conditions, were compared for their chemical composition and nutritional quality. The local cultivar Kurram contained the maximum protein (28.3%) and the imported cultivar No. 45 contained the maximum oil content (49.5%). K, Mg, P, Fe, Zn, Cu and Mn were present in nutritionally significant and comparable amounts in all the cultivars. Lysine was the first limiting amino acid in all the cultivars. The chemical scores and net protein utilization (operative) values were higher for the imported than local cultivar while net dietary protein calories percent (NDP Cal%) values showed only minor variations among the five cultivars. Significant differences (P<0.05) were observed for protein, oil, Na, K, Ca, P and Zn contents of all the cultivars. Roasting (150°C, 1/2 h) decreased the lysine, threonine, methionine, cystine, arginine, tryptophan and tyrosine contents but increased the protein, oil, ash, fiber, mineral elements (except Na and C1), aspartic acid, serine, glutamic acid, proline and phenylalanine contents.  相似文献   
116.
117.
A study was performed to investigate the influence of dietary lactoferrin (LF) on growth and stress responses of juvenile Siberian sturgeon. Fish were fed six experimental diets (0, 100, 200, 400, 800, and 1600 mg LF/kg diet) for 10 wk. At the end of the experiment, fish were exposed to an acute stressor of 2‐min air exposure. The levels of cortisol, glucose, and lactate were measured before and at 1, 3, 6, 9, 12, and 24 h after stress. LF supplementation did not influence the fish growth. Cortisol and lactate, but not glucose level, were significantly affected by dietary LF. Cortisol levels in the control group rose twofold 1 h after stress and were significantly higher than that in LF groups. Moreover, the lowest level of cortisol at all sampling times (prestress and poststress) was observed in fish fed 400 mg LF/kg diet. Lactate concentrations in sturgeon fed 400 mg LF/kg markedly rose 1 h after stress, albeit changes in other LF groups were not significant. Results of this study show that dietary LF can suppress the stress responses in Siberian sturgeon, while 400 mg LF/kg diet appears to be an effective dietary level for this species to reduce stress.  相似文献   
118.
Draught animal technology (DAT) can potentially play a central role in agriculture transformation for traditional farmers. This study surveyed the state of DAT in En-Nhoud area, North Kordofan State, Sudan in an attempt to have a clear view of the changes brought about by introducing the technology. The study followed the cross-sectional survey design. Farmers were selected from ten clusters (villages) and data were collected using questionnaires and face to face interviews with farmers in addition to group discussions with them and the different actors in the field. The results showed that farmers appreciate the role played by DAT, but they highlighted the need for further capacity building and technical backup. Harnessing issues are not well understood and applied by the farmers. The different actors involved in DAT in the area lack networking and coordination, and this reflected on the many problems and constraints faced by the farmers.  相似文献   
119.
The biological effects of two important medicinal plants, Artemisia annua L. and Achillea millefolium (L.) (viz, mortality, growth, and feeding indices as well as enzyme and non-enzymatic activities) were studied on small white Pieris rapae L a deleterious pest of cruciferous plants under controlled conditions (16:8 h L:D at 25 ± 1 °C and 65 ± 5% RH). The LC50 and LC25 values were 9.387% and 3.645% for A. annua L. and 4.19% and 1.69% for A. millefolium (L.), respectively. At the lowest concentration (0.625%), the deterrency was 29.826% and 44.185% for A. annua L. and A. millefolium (L.), respectively. Feeding indices were variously affected with changes in a number of parameters and an increase in larval and pupal duration. The activity level of alkaline phosphatase increased sharply while alanin and aspartate aminotransferases showed a sharp decrease. For non-enzymatic compounds, the amount of glucose and uric acid increased, but total protein and cholesterol decreased. These results indicate that these two medicinal plants might possess potential secondary metabolites that may be useful for controlling potential insect pests.  相似文献   
120.
Little quantitative information is available on animal power in the Nile Valley in Sudan, despite that it is being used in the area for centuries and playing an important role in agriculture in the present day. A survey was conducted to assess draught oxen management and its association with field capacity and efficiency at the farm level and to identify potential areas for intervention. A sample of 50 farmers was selected for this purpose using the systematic random sampling technique. The main management parameters discussed were animal health, feeding, housing, work strategy and care for yoke and plough. The results showed that most of the farmers poorly manage their animals, and this was reflected in low working speeds and field efficiencies. The main dimensions of poor management were in veterinary care (78 % did not take their animals to the veterinary centre), feeding (66 % feed their animals shortly before work) and care for yoke (80 % did not follow daily care measures for their yokes) and plough (74 % did not follow plough care measure before and after work). Low working speeds (0.90–2.0 km/h) were recorded by the majority of the farmers (64 %). The majority of the farmers (70 %) recorded field capacities between 0.06 and 0.10 ha/h, while all of them worked at high field efficiencies of >86 %. The only parameter that significantly affected field capacity was the yoke-related wounds (p?=?0.019). Extension advice and capacity building in husbandry and working practices were identified as principal entry points for intervention.  相似文献   
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