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稀土元素的植物生理效应 总被引:97,自引:3,他引:97
国内外大量研究资料表明,在适宜条件下,稀土对植物的许多生理功能都有积极影响,是植物的有益元素,但尚不能证明它是植物的必需营养元素。本文综合介绍了稀土元素在植物体内的含量、分布,以及对植物萌发、生长、营养代谢、光合作用和抗逆、抗病等生理方面的影响效应,并对其作用机制作了些讨论,以资参考。 相似文献
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稀土元素在植物中的生理效应 总被引:10,自引:0,他引:10
稀土元素是元素周期表中57-71的15个镧系元素及与其性质十分相似的抗钇共17种元素的统称,本文概述了稀土元素对改善植物矿质营养、促进植物光合作用,增强植物抗逆性方面的生理效应,还讨论了稀土元素与植物激素间关系。 相似文献
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植物空间诱变的生物效应及其育种研究进展 总被引:34,自引:0,他引:34
概述了空间环境对植物的诱变效应及植物空间诱变育种的研究进展,并提出了目前植物空间诱变研究存在的问题及今后的研究方向。 相似文献
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酸雨(Acid rain)是当代重大环境污染问题之一。中国已成为继西欧和北美之后的全球第三大酸雨区,酸雨发生面积约120万平方千米,重酸雨发生面积约6万平方千米[1]。同时,中国也是稀土(Rare earth,RE)资源大国,RE对作物具有优质增产的生物学效应且农业经济效益显著[2],一度作为政府行为得到广泛应用。仅2006年,农用稀土达4 800吨(以 相似文献
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概述了国内外露水对植物作用效应争议的两个方面,一是露水有利于促进植物生长,二是露水对植物生长具有负效应。前者主要包括干旱胁迫下植物生长重要的水资源、调节植物体内水分、改善土壤水分平衡、调节森林植物生长环境、有利于农作物管理及其病虫害防治等生态效益;后者包括导致植物发病、降低植物产量和质量等。文章还指出了露水对植物作用效应研究存在的问题,并提出了今后研究的方向:(1)露水对植物作用效应的机理研究;(2)干扰条件下露水对植物作用效应研究包括酸露对植物作用效应研究和城市热岛条件下露水对植物作用效应研究;(3)露水对植物多样性的影响研究;(4)露水在生物防治中的应用研究。 相似文献
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Distribution pattern of rare earth elements in fern 总被引:1,自引:0,他引:1
All the lanthanide elements (REE) in fern (Matteuccia) and in soil were determined with inductively coupled plasma mass spectrometer (ICP-MS) in order to discuss REE behavior
in fern. The fern sample was divided into three parts: root, stem, and leaf; the soil of the same site was also sampled and
the soil sample was divided into two parts: HCl and HNO3 soluble part (soil[HCl]) and HF soluble part (soil[HF]). REE in each part was determined by ICP-MS after solvent extraction
separation. The overall variation of the REE pattern of the root does not resemble that of the whole soil, but that of the
HF soluble part. A tetrad effect variation (W-type) was found in the REE patterns of root, stem and leaf; more conspicuous
tetrad effect variation was observed in HREE region than in LREE region, and was so in stem and leaf than in root. Negative
anomalies of Ce were observed in the REE patterns of root, stem and leaf, with bigger anomalies in stem and leaf than in root.
The results of this study suggest that REE in fern has come from silicates of soil and has once been in dissolved state. 相似文献
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稀土对蚯蚓体内氨基酸含量的影响 总被引:4,自引:1,他引:4
采用滤纸接触染毒法,分别进行了氯化稀土、氯化镧与土居动物蚯蚓接触染毒不同时间和不同浓度的试验。研究其对蚯蚓体内氨基酸含量的影响变化。结果表明。Re、La对蚯蚓体内的氨基酸含量影响较显著,在低浓度时总体表现为促进蚯蚓体内氨基酸的形成,而在高浓度状态下则使蚯蚓体内氨基酸含量下降,产生抑制作用,两种稀土在400mg·L^-1浓度时,蚯蚓体内氨基酸含量除脯氨酸外开始上升,随着作用时间延长,氨基酸含量逐渐下降,在100~1200mg·L^-1浓度范围,两种稀土均引起蚯蚓体内脯氨酸含量的下降,产生抑制作用。 相似文献
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Concentrations and flux of rare earth elements in a semifield plot as influenced by their agricultural application 总被引:1,自引:0,他引:1
The concentrations of rare earth elements (REs) in atmospheric particles, soil, soil water, surface runoff, and different
parts of corn in an experimental plot in the suburb of Beijing, China were measured and the flux of REs was estimated. The
concentration of REs in air particles with diameter less than 10 μm is 36 ng/m3 and, by ratio analysis, the origin of REs in the atmosphere was likely local soil. The concentration of soluble REs is 0.69
μg/L in rainwater, 5–7 μg/L in surface runoff, as well as 1–4 μg/L in soil water and the application of RE mixture has no
observed influences on their concentrations. The concentration of soluble REs in surface runoff and soil water was dominated
by aqueous-solid-phase partitioning. By estimation of the flux, most of the REs applied will remain in the soil phase and
continued application of REs will cause an accumulation of REs in agricultural soil. 相似文献
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DING ShiMing LIANG Tao YAN JunCai ZHANG ZiLi HUANG ZeChun & XIE YaNing 《中国科学:生命科学英文版》2007,50(1):47-55
Fractionations of rare earth elements (REEs) and their mechanisms in soybean were studied through application of exogenous mixed REEs under hydroponic conditions. Significant enrichment of middle REEs (MREEs) and heavy REEs (HREEs) was observed in plant roots and leaves respectively, with slight fractionation between light REEs (LREEs) and HREEs in stems. Moreover, the tetrad effect was observed in these organs. Investigations into REE speciation in roots and in the xylem sap using X-ray absorption spectroscopy (XAS) and nanometer-sized TiO2 adsorption techniques, associated with other controlled experiments, demonstrated that REE fractionations should be dominated by fixation mechanism in roots caused by cell wall absorption and phosphate precipitation, and by the combined effects of fixation mechanism and transport mechanism in aboveground parts caused by solution complexation by intrinsic organic ligands. A conceptive model was established for REE fractionations in plants based on the above studies. 相似文献
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Fractionations of rare earth elements (REEs) and their mechanisms in soybean were studied through application of exogenous
mixed REEs under hydroponic conditions. Significant enrichment of middle REEs (MREEs) and heavy REEs (HREEs) was observed
in plant roots and leaves respectively, with slight fractionation between light REEs (LREEs) and HREEs in stems. Moreover,
the tetrad effect was observed in these organs. Investigations into REE speciation in roots and in the xylem sap using X-ray
absorption spectroscopy (XAS) and nanometer-sized TiO2 adsorption techniques, associated with other controlled experiments, demonstrated that REE fractionations should be dominated
by fixation mechanism in roots caused by cell wall absorption and phosphate precipitation, and by the combined effects of
fixation mechanism and transport mechanism in aboveground parts caused by solution complexation by intrinsic organic ligands.
A conceptive model was established for REE fractionations in plants based on the above studies. 相似文献
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长期喷施稀土对土壤-植物(小麦)系统中稀土元素分布、累积及运移的影响 总被引:16,自引:1,他引:16
在我国施用稀土时间最长的黑龙江省花园农场,研究比较了施用稀土12 a和不施稀土的对照处理上小麦和土壤中的稀土元素的分布、累积及运移.结果表明,长期叶面喷施稀土并未造成耕层土壤和下部土层的稀土元素的累积.成熟期小麦植株各部位的稀土元素含量顺序为根>叶>茎、壳;稀土元素主要累积在根部,其次是叶,茎和壳累积较少.喷施处理小麦根部的稀土元素累积量高于对照,叶部也有此趋势,而茎、壳等部位差异不大.根、茎、叶、壳稀土元素分布模式与土壤中相似,与施用的常乐稀土差别较大;长期喷施稀土未曾造成籽粒中稀土元素的明显累积. 相似文献