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131.
Vegetables are vital to the human diet, and in particular provide the well-known nutrients to maintain normal physiological functions. The prolonged application of large amount of fertilizers and pesticides has resulted in heavy metal accumulation in vegetable gardens. Exposure to heavy metals by the consumption of contaminated vegetables and its toxicity is a serious concern. This article reviews the presence of heavy metals in different vegetables, their mechanism of absorption, impact of heavy metals on physiology, and nutrient reduction and associated impact on humans with emphasis on pregnant women based on the existing scientific literature. However, a limited number of studies was found in the data base that examined the reduction of nutrients in the vegetables due to heavy metal contamination. The heavy metals were found in 36 vegetables in 61 regions of the world and were above permissible limits in most of the vegetables. Specific study to human toxicity due to the contamination of heavy metals may be conducted with emphasis on pregnant women, children, and elderly people. Furthermore, strategy and policy should be devised to control the heavy metals in vegetables and those vegetables that are hyper-accumulators of heavy metals should be identified for awareness purposes. 相似文献
132.
Allen V. Barker Touria E. Eaton Md J. Meagy Emad Jahanzad Gretchen M. Bryson 《Journal of plant nutrition》2017,40(17):2432-2439
An improvement in the mineral nutrient contents of fruits and vegetables is needed to offset reported declines in concentrations of these elements in fruits and vegetables. The declines have been associated with the high productivity of modern cultivars and to depleted soil fertility. This research addressed differences in mineral nutrient concentrations between modern F1 hybrids and heirloom cultivars of cabbage (Brassica oleraceae var. capitata L.)and among fertilization practices with conventional chemical or organic fertilizers and compost. Crop production was greater with the chemical or organic fertilizers than with the compost. Mineral nutrient composition did not vary between modern or heirloom cultivars or among fertilization regimes but varied among cultivars, suggesting that cultivar selection could lead to production of nutrient-rich cabbage. Neither mass of heads nor days to maturation of crops affected nutrient composition. 相似文献
133.
Dragana Jurić Dinko Puntarić Vlatka Gvozdić Zdenko Lončarić Ada Puntarić 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(3):270-277
Biomonitoring of the local population and environmental monitoring in eastern Croatia have revealed abnormalities in metal and metalloid distribution that could be related to war activities during the 1990s. The goal of this study was to determine whether there are differences in the concentrations of metals and metalloids by comparing locations of high and low-intensity combat activity; we also evaluated a possible connection between metal contamination in soil and in humans. We sampled 14 locations and measured the concentrations of 20 war related metals and metalloids (Al, As, B, Ba, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Ni, Pb, Sb, Si, Sr, U, V and Zn). The results of principal components analysis showed two main clusters: locations Dopsin and Dalj (both characterized by high-intensity combat activity), where the concentrations of most elements (except Hg) were increased. Although the concentrations of metals and metalloids in cabbage samples collected in eastern Croatia did not exceed the maximum allowed values, the results of our study confirmed existance of environmental ‘hotspot’ with higher concentrations of war metals and metalloids. Our findings indicate that there is a possible common source and mechanism of transferring metals from the environment to the population. 相似文献
134.
Nesrine Razgallah Hela Chikh-Rouhou Iteb Boughattas 《Archives of Agronomy and Soil Science》2016,62(4):473-483
This study reports the nitrate level of 22 vegetables species collected from 40 farms in several locations of an intensive agricultural area in two regions of Tunisia (Sousse and Monastir). Nitrate levels ranged between 57 and 2970 mg kg?1. The highest and the lowest levels were found in turnip and tomato, respectively. Only five species (potato, field bean, cauliflower, pea and artichoke) had exceeded the norms established by the World Health Organization. Factors influencing nitrate accumulation in some vegetables were analyzed and discussed. It was observed that nitrate contents in vegetables varied depending on the type of vegetables, genetic factor, level of nitrogen fertilization and soil nitrogen content. 相似文献
135.
欧洲水培叶菜机械规模化生产系统 总被引:2,自引:0,他引:2
针对水培叶菜规模化生产,介绍了欧洲水培叶菜自动化生产装备系统与技术。首先,说明水培技术高效循环生产、避免土壤环境污染的优势,论述了水培叶菜的主要作业流程。基于水培叶菜作业流程,通过实物图片介绍了欧洲水培叶菜生产中基质处理、精量播种、种苗移植、叶菜收获和生产资材自动输送等环节装备和技术。对比国内水培蔬菜的生产模式与具体国情,提出了研学欧洲先进的生产作业装备技术和物流化生产作业思想理念,结合我国水培蔬菜生产模式,优化完善叶菜丸粒化精量播种技术,开发研制叶菜种苗移植设备,针对不同水培叶菜生产企业及生产方式,量身定制开发设计物流化生产输送系统,达到提高生产效率、降低劳动强度、减少生产劳动力的目的,有效提高我国水培蔬菜生产的竞争力。 相似文献
136.
137.
研究果蔬的压缩力学性质可为果蔬加工、运输、检测包装等生产环节提供设计参数及工艺优化依据。为此,以几种常见果蔬为研究对象,在INSTRON生物材料性能试验机上搭载了电子显微镜图像采集系统,在进行果蔬试样压缩力学性质试验测试的同时,对压缩变形过程进行了动态图像采集与分析,获得了果蔬的压缩强度极限、弹性模量等力学性质指标。同时,结合电子显微镜采集到的压缩过程果蔬细观结构变形图像,通过观察压缩过程果蔬细胞的变形、微结构变位及渗水等情况,分析了果蔬材料的屈服强度、压缩强度及材料破坏与细观结构变位的关联,了解了果蔬压缩力学性质与压缩过程中细观结构变位的动态响应。 相似文献
138.
139.
节节麦与野燕麦8倍体杂种核型分析 总被引:1,自引:0,他引:1
节节麦(Aegilops tauschii(Coss.)Sch.2n=2x=14)与通北野燕麦(Avena fatua L.2n=6x=42)杂交,F_1自然加倍成8倍体,8倍体播成的F_2代,遗传性基本一致,PMC镜检表明,染色体数为2n=28Ⅱ。用F_2所结的种子进行根尖细胞核型分析,结果发现8倍体中包含有全套的节节麦和野燕麦的染色体。节节麦中有1对随体染色体.2对近中部着丝点染色体,4对中部着丝点染色体。野燕麦有3对随体染色体,5对近端着丝点染色体,8对近中部着丝点染色体,5对中部着丝点染色体。而节节麦与野燕麦8倍体杂种,有4对随体染色体,5对近端着丝点染色体.10对近中部着丝点染色体,9对中部着丝点染色体。核型分析结果表明,节节麦与野燕麦杂交合成的8倍体,是节节麦与野燕麦的双二倍体。 相似文献
140.