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61.
In developing countries, farmers use effluent as a source of irrigation and nutrients and the government takes this practice as a viable option for disposal. Sewage samples have hazardous electrical conductivities (EC), sodium adsorption ratios (SARs), and residual sodium carbonate (RSC) for irrigation, but metals were close to upper permissible limits. The EC of saturated soil paste extract (ECe) ranged from 2.18 to 4.02 dS m–1 and soil SAR 7.72 to 16.00 in soils 0.2 m deep. Average cadmium (Cd), nickel (Ni), lead (Pb), zinc (Zn), and copper (Cu) in soils ranged from 0.02 to 0.13, 0.00 to 4.45, 2.27 to 4.57, 0.71 to 13.76, and 3.17 to 10.37 mg kg–1, respectively. Plants acquired metal contents greater than in raw sewage or soils. The wide biodiversity regarding metals in shoots of natural and planted vegetation that receives raw sewage is of practical significance. It seems imperative to study under controlled conditions various plants' metal tolerance and mechanisms of metal partitioning among plant parts.  相似文献   
62.
The edible seeds of the quinoa plant contain small quantities of alcohol-soluble protein which, after peptic-tryptic digestion, are unable to agglutinate K562(s) cells. When separated by affinity chromatography on sepharose-6B coupled with mannan, peptic-tryptic digest separated in two fractions. Fraction B peptides (about 1% of total protein) were shown to agglutinate K562(s) cells at a very low concentration, whereas peptides in fraction A and in the mixed fraction A+B were inactive, suggesting that fraction A contains protective peptides that interfere with the agglutinating activity of toxic peptides in fraction B.  相似文献   
63.
高锦红 《安徽农业科学》2011,39(4):1908-1909
[目的]讨论常见谷物中微量元素的分布及相关性。[方法]用火焰原子吸收分光光度法测定了6种陕西常见谷物中微量元素Fe、Mn、Cu、Zn和Ca的含量。[结果]不同地区由于土壤、气候等因素不同,所产粮食中微量元素存在一定差别。[结论]采用对应分析法对谷物微量元素相关性进行分析是可行的。  相似文献   
64.
Studies of a spectrum of metabolites found in cereals are becoming one of the primary tools for evaluating their susceptibility to the effects of various environmental agents, such as: pathogens, temperature and precipitation. In order to reduce the effect of the environmental conditions, cultivars were grown under identical cultivation conditions.  相似文献   
65.
中国粮食作物单产增长规律及其原理   总被引:2,自引:1,他引:1  
应用距平值法和方差分析法,对我国1978—2007年的粮食单产增加原理进行了分析。结果表明,我国粮食单产呈周期性增加规律,粮食单产周期性增加是作物品种周期性更新的结果,作物品种最高产量施肥量是品种的重要营养遗传特性,是品种适应土壤环境条件的结果。因此,肥料施用量的周期性增加是作物品种更新的重要原因。近30年来,我国作物品种潜力水平的提高,主要是利用了育种材料的耐氮肥特性,而没有利用品种营养平衡的遗传特性,结果导致单位肥料的增产量逐年降低。  相似文献   
66.
A method for the fractionation of wheat, rye, and barley flours without using aqueous solvents was developed. The separation of protein and starch was based on differences in their densities. Therefore, ball-milled flour was suspended in a mixture of inert solvents (toluene/tetrachoroethene) with a density of 1.47 g/cm3 and centrifuged. Owing to its higher density, the starch fraction was obtained as sediment whereas the protein fraction (PF) formed a layer on the surface of the solvent because of its lower density. The PF was enriched in a solvent mixture with a density of 1.355 g/cm3 yielding a middle fraction (sediment) and the enriched PF (upper layer). The latter was then defatted with toluene (0.87 g/cm) providing a lipid fraction in addition. The influence of ball milling under air or in the sedimentation solvent on the yield and the purity of the fractions was studied. Three varieties of wheat, and one rye and barley variety were fractionated by the optimised method and the obtained fractions were characterised by chemical methods e.g. gel permeation chromatography, SDS electrophoresis, and a combined extraction/HPLC method.  相似文献   
67.
Water shortage is the major bottleneck that limits sustainable development of agriculture in north China. Crop physiological water-saving irrigation methods such as temporal (regulated deficit irrigation) and spatial (partial root zone irrigation) deficit irrigation have been tested with much improved crop water use efficiency (WUE) without significant yield reduction. Field experiments were conducted to investigate the effect of (1) spatial deficit irrigation on spring maize in arid Inland River Basin of northwest China during 1997–2000; (2) temporal deficit irrigation on winter wheat in semi-arid Haihe River Basin during 2003–2007 and (3) temporal deficit irrigation on winter wheat and summer maize in Yellow River Basin during 2006–2007. Results showed that alternate furrow irrigation (AFI) maintained similar photosynthetic rate (Pn) but reduced transpiration rate (Tr), and thus increased leaf WUE of maize. It also showed that the improved WUE might only be gained for AFI under less water amount per irrigation. The feasible irrigation cycle is 7d in the extremely arid condition in Inner River Basin of northwest China and less water amount with more irrigation frequency is better for both grain yield and WUE in semi-arid Haihe River Basin of north China. Field experiment in Yellow River Basin of north China also suggests that mild water deficit at early seedling stage is beneficial for grain yield and WUE of summer maize, and the deficit timing and severity should be modulated according to the drought tolerance of different crop varieties. The economical evapotranspiration for winter wheat in Haihe River Basin, summer maize in Yellow River Basin of north China and spring maize in Inland River Basin of northwest China are 420.0 mm, 432.5 mm and 450.0 mm respectively. Our study in the three regions in recent decade also showed that AFI should be a useful water-saving irrigation method for wide-spaced cereals in arid region, but mild water deficit in earlier stage might be a practical irrigation strategy for close-planting cereals. Application of such temporal and spatial deficit irrigation in field-grown crops has greater potential in saving water, maintaining economic yield and improving WUE.  相似文献   
68.
In the last decade the gluten free market has grown rapidly, driven by a greater awareness of coeliac disease and gluten intolerance, but also by consumers choosing to follow a gluten-free diet. This has resulted in a greater range of higher quality products being available, however the nutritional profile may still be inferior, and the taste and texture is not the same as traditional wheat-based products. Epitopes in glutenins and gliadins that cause coeliac disease are well characterised, and research efforts are focused on understanding the impact of environmental and management practices on the expression of these proteins, as well as strategies to remove these epitopes, both through conventional breeding and genetic engineering. Here we provide an overview of these research efforts, the potential impact on end product quality as well as current research to accurately quantify the gluten content in foods and beverages to ensure the safety of products for those who are required to avoid gluten for medical reasons.  相似文献   
69.
Cereal-based products, such as bread, are staple foods in the western diet. Due to the nature of their basic ingredients and the diversity of recipes, the amount of fermentable short-chain carbohydrates (FODMAPs) in those products may be high. This study characterized the FODMAP-profiles of a broad range of cereal-product ingredients, serving as a basis for low FODMAP product development. Different cereals, pseudo-cereals, gluten-free flours, pulses, pulse protein ingredients, commercial sprouts, and other cereal-product ingredients were analyzed, using anion-exchange chromatography with electrochemical detection. Wheat and related cereals were high in fructans. Pulses, such as peas contained high galactooligosaccharides (GOS) amounts. Whereas GOS levels in pulse protein ingredients varied, depending on their production. Gluten-free flours, for instance, rice-flour, showed low FODMAP-profiles. Amongst those, buckwheat, which does not contain any of the FODMAPs investigated, contained high amounts of other soluble non-digestible carbohydrates, namely fagopyritols; these may have a similar effect on a sensitive gut as GOS. Finally, ingredients contained mainly high levels of fructans and GOS. Yet, the analysis of commonly consumed commercial cereal products, including bread, pasta, crackers and biscuits, highlighted the relevance of lactose, fructose in excess of glucose and polyols. These products serve as benchmarks for further product development.  相似文献   
70.
《Journal of Crop Improvement》2013,27(1-2):239-255
SUMMARY

Crop production in the North is constrained by a short growing season, spring and autumn frosts, long winters with deep snow cover and low temperatures during the growing season. Increase in concentration of atmospheric CO2 and other greenhouse gases, and the subsequent increase in ambient temperatures could benefit crop production in countries located in the North, including Finland. However, longer growing seasons, milder winters and higher growing season temperatures could increase the occurrence of pests and pathogens, and ultimately decrease crop yields and the net income of farmers. Benefits to be gained from increased tillering and higher numbers of grains per unit area resulting from elevated CO2 levels might be smaller than expected in countries like Finland, where the uniculm growth habit of cereals is maintained by the long days that characterise the growing season.  相似文献   
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