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1.
铁在苹果树器官中的定量研究   总被引:1,自引:0,他引:1  
成龄苹果树整株分析结果表明 ,果实、叶片、枝干、根系的鲜重分别占整株鲜重的 42 .0 9%、6 .33%、38.81%、12 .77% ,以果实占鲜重的比例最大 ,单株鲜重为 2 0 7.90kg ;果实、叶片、枝干、根系的干重分别占整株干重的 19.5 1%、6 .45 %、5 7.30 %、16 .75 % ,以枝干占干重的比例最大 ,单株干重 84.37kg ,单株含水量 12 3.5 5kg。铁浓度以直径 <0 .5cm的根最高 ,达 2 5 7.5 1mg/kg ,其次为叶片 ,达 2 14.0 9mg/kg ,果实中铁浓度最低 ,为 18.2 7mg/kg;单株总铁含量 4915 .78mg,叶、果、根、枝干中铁含量分别为 116 4.6 5、30 0 .72、15 0 0 .30、1949.6 0mg ,分别占单株总铁量的2 3 .70 %、6 .12 %、30 .5 2 %和 39.6 6 %。  相似文献   
2.
靠接红桔、酸桔和枸头橙砧,矫治枳砧甜橙缺铁黄化有明显效果。其中,以枸头橙效果最好,以下依次为酸桔和红桔,靠接砧苗后树势逐年恢复,产量成倍增加,靠接红桔、酸桔和枸头橙分别比对照增产3.3、1.4和1.5倍;对提高果实含糖量、果汁率和降低含酸量亦有良好效果。  相似文献   
3.
根据调查初步总结出山楂缺铁黄叶病的发生发展规律、致病因素及其对山楂生产的危害。用新研制的高效价廉、储运方便的硝黄铁矫治,效果明显。黄化病株复绿率40%~87%,三级病株减少36%~100%,叶绿素含量提高64%~224%,喷肥区比对照区株产提高25%。同时增加了果实中糖、酸、果胶及钙、铁含量,提高了果实品质。  相似文献   
4.
嫁接方法、环剥对铁在果树体内的分配有影响。59Fe试验结果表明,室内营养液培养的2年生长富2/八棱海棠腹接、劈接和切接叶中59Fe的分配比例分别为4.10%、1.06%、1.21%,腹接的品种叶中铁含量显著高于劈接和切接,环剥明显影响铁在叶中的含量,室内营养液培养的八棱海棠苗在环剥、环割和不处理对照叶中59Fe的分配比例分别为8.1%、17.2%、31.7%,各处理间差异均达显著水平。  相似文献   
5.
Abstract

Analytical data for Al and Fe extracted by different reagents is presented. It is concluded from the data that in podsolisation Al migrates mainly as inorganic gel while iron moves as organic chelated complexes.  相似文献   
6.
《Journal of plant nutrition》2013,36(10-11):2009-2021
Abstract

A collaborative assay among three laboratories was made in order to compare both the ion (CEN. EN 13368‐2:2001 E. Determination of chelating agents in fertilizers by ion chromatography. Part 2: EDDHA and EDDHMA, 2001a) and the ion‐pair (Lucena, J.J.; Barak, P.; Hernandez‐Apaolaza, L. Isocratic ion‐pair high‐performance liquid chromatographic method for the determination of various iron(III) chelates. J. Chromatogr. A 1996, 727, 253–264) high performance liquid chromatography (HPLC) methods as well as the soluble and complexed Fe (CEN. EN 13366:2001 E. Treatment with a cation exchange resin for the determination of the chelated micronutrient content and of the chelated fraction of micronutrients, 2001b) methods. Fifteen and ten samples of commercial fertilizers of Fe‐EDDHA, Fe‐EDDHMA, respectively were analysed by three laboratories using these methods. No significant differences were observed between the results obtained for the Fe‐EDDHA content using the Lucena et al. or CEN method. The first method makes it possible to distinguish between the meso and DL‐racemic diasteroisomers of Fe‐o, o‐EDDHA. For the Fe‐EDDHMA formulations, the CEN method gives higher values than the ion‐pair method, since in the first one Fe‐EDDH4,6MA coelutes with FeEDDHMA. Also the CEN method does not makes it possible to distinguish between Fe‐EDDHMA and Fe‐EDDH5MA products. The variability among laboratories was larger for the CEN method than for the Lucena et al. method.  相似文献   
7.
AIM:To investigate the role of reative oxygen species (ROS) generated by iron overload in activating the mitogen-activated protein kinase (MAPK) pathways and apoptosis. METHODS:Cultured human osteoblast cell line hFOB1.19 was treated with ferric ammonium citrate (FAC) at concentrations of 0~500 μmoL/L. The proliferation of hFOB1.19 cells was analyzed by MTT assay. Apoptosis was detected by flow cytometry with Annexin V/PI staining. The expression levels of p-ERK, p-JNK and p-p38 were determined by Western blotting 24 h after treatment with FAC. RESULTS:After treated with FAC, the cell proliferation was inhibited. The early apoptosis and total cell death were significantly increased. The levels of ROS were increased to (35.73±2.52)%, (62.89±4.24)% and (76.06±3.55)% with the increasing doses of FAC treatmen,respectively. The expression levels of p-ERK, p-JNK and p-p38 were also remarkably elevated in FAC groups. CONCLUSION:Iron overload increases intracellular ROS level, thus triggering the MAPK pathways and inducing apoptosis of human hFOB1.19 osteoblast cells.  相似文献   
8.
Greenhouse experiment was conducted to assess the iron (Fe) and zinc (Zn) fractionation patterns in soils of arbuscular mycorrhizal (AM) fungus-inoculated and uninoculated maize plants fertilized with varying levels of Fe and Zn. Soil samples were collected for Fe and Zn fractions and available Fe, Zn and phosphorus (P) contents besides organic and biomass carbon (BMC), soil enzymes and glomalin. Major portion of Fe and Zn fractionations was found to occur in the residual form. Mycorrhizal symbiosis increased the organically bound forms of Fe and Zn while reducing the crystalline oxide, residual Fe and Zn fractions, indicating the transformation of unavailable forms into available forms. Soil enzymes, viz. dehydrogenase and acid phosphatase activities in M+ soils, were significantly higher than M? soil consistently. Overall, the data suggest that mycorrhizal symbiosis enhanced the availability of Fe and Zn as a result of preferential fractionation and biochemical changes that may alleviate micronutrient deficiencies in calcareous soil.

Abbreviations: AM: arbuscular mycorrhiza; Fe: Iron; Zn: Zinc; P: Phosphorous; Amox-Zn: amorphous oxide bound zinc; Cryox-Zn: crystalline oxide bound zinc; DAS: days after sowing; DTPA: diethylene Triamine Penta Acetic Acid; MnO2-Zn: manganese oxide bound zinc; OC-Zn: organically bound zinc; WSEX: water soluble plus exchangeable zinc; MnO2 Fe: manganese oxide bound iron; OC-Fe: Organically bound iron; WSEX Fe: water soluble plus exchangeable iron.  相似文献   
9.
There has been less concern about soil mineralogical alteration than about soil physical, chemical and biological changes induced by termite nest-building activity. Furthermore, much less attention has been paid to free sesquioxides than to phyllosilicate minerals. In the present study, we conducted field morphological observations and selective dissolution analysis to characterize free sesquioxides in termite (Macrotermes bellicosus) mounds as compared with surrounding pedons in different toposequence positions, i.e., seasonally flooded valley bottom, hydromorphic fringe and well-drained upland sites. Distinctive redoximorphic features, such as surface yellowish layers on mound structures from the fringe site, indicate possible alteration of iron sesquioxide forms in the mounds due to the transportation of soil from reductive (aquic subsoil) to oxidative (epigeal mound) environments by the nest-building activity of M. bellicosus. On the other hand, the iron-soluble content in the dithionite-citrate-bicarbonate (DCB) system (Fed) was generally higher in the mound structures than at the adjacent sub-surface (Ap2) horizon at each toposequence position, while there was less difference in the content of acid ammonium oxalate (AAO) extractable iron (Feo) as compared to Fed. As a consequence, the iron activity index (Fed/Feo ratio) was found for the most part to be lower in the mound structures than in the neighboring Ap2 horizon. In addition, the content of Fed, AAO-soluble Al (Alo) and DCB-extractable Al (Ald) was significantly correlated with clay content in these soils. These findings suggest that M. bellicosus preferentially collects clay particles, probably from the clay-rich subsoils, such as the argillic horizon, which has been formed by the co-migration of phyllosilicate minerals and relatively crystalline sesquioxides. The species then likely incorporates them into the mounds, which induces an increase in the Fed content relative to that of Feo, resulting in a decreased iron activity index in the mound structures.  相似文献   
10.
芹菜对铁的吸收及铁对其生长和品质的影响   总被引:2,自引:0,他引:2  
通过调节水培营养液中铁浓度分别为0,0.7,1.4,2.8,5.6,8.4,11.2和14.0.mg/L的8个水平种植4个芹菜品种,研究了不同铁供应水平对芹菜生长和植株铁含量及其品质的影响。结果表明,0.7mg/L浓度下,芹菜生长良好,没有表现缺铁症状,1.4mg/L浓度时,叶片中的铁含量达最大值,2.8mg/L浓度下,芹菜产量,Vc、蛋白质、叶绿素含量较高,硝酸盐含量较低。在各铁供应水平下4个芹菜品种均未出现铁中毒现象。供铁以后,其供应量对芹菜叶中钙、镁含量影响不大;锌含量与营养液中铁浓度呈负相关,铁锌之间表现出离子竞争作用。  相似文献   
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