首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.

Natural manganese oxide nanoparticles and grain coatings profoundly impact contaminant cycling in the environment through their ability to degrade organic compounds and sequester metal ions. Previous studies of biogenic manganese oxides have shown that the interlayer cation may have an important effect on the resulting oxide structure. The effect of Na and Ca ions was investigated to determine their fundamental roles in the stabilization of the phyllomanganate biooxide structure, its unit cell symmetry, and order/disorder relations. Biogenic oxides were created by incubating Mn(II) with spores of the marine Bacillus sp., strain SG-1 and the resulting oxide structures examined using X-ray absorption spectroscopy and X-ray diffraction to determine the short-range and long-range atomic structure. Phyllomanganates were observed exclusively, with differing degrees of layer stacking disorder, degree of crystallinity, and layer symmetry, depending on the cation present. In general, Ca was found to promote biooxide long-range order. We conclude that the presence of Ca in these oxides will confer greater stability to these bacteriogenic manganese bioxodes.  相似文献   

2.
Summary Oats, vetch, and rye were grown as successive crops in pots of a manganese-deficient soil to which -MnO2 had been added in increasing amounts. Manganese deficiency of oats was overcome with 32 ppm of added manganese. Additions of 10, 18 and 32 ppm caused a decrease in concentration of maganese in the plants. Vetch and rye were unaffected by manganese deficiency and kept on accumulating manganese with increasing additions to the soil. Of the three plants vetch showed the greatest uptake of manganese, both with and without added manganese.  相似文献   

3.
The development of advanced cathode materials for aqueous the zinc ion battery (ZIB) represents a crucial step toward building future large‐scale green energy conversion and storage systems. Recently, significant progress has been achieved in the development of manganese‐based oxides for ZIB via defect engineering, whereby the intrinsic capacity and energy density have been enhanced. In this review, an overview of the recent progress in the defect engineering of manganese‐based oxides for aqueous ZIBs is summarized in the following order: 1) the structures and properties of the commonly used manganese‐based oxides, 2) the classification of the various types of defect engineering commonly reported, 3) the various strategies used to create defects in materials, and 4) the effects of the various types of defect engineering on the electrochemical performance of manganese‐based oxides. Finally, a perspective on the defect engineering of manganese‐based oxides is proposed to further enhance their electrochemical performance as a ZIB cathode.  相似文献   

4.
Summary A laboratory study, three glasshouse tests and eight field experiments on commercial farms in East Anglia during 1972 to 1974 tested the effect of incorporating manganese in the coating of pelleted seed on the manganese nutrition and yield of sugar beet. The pelleting material readily absorbed manganese from solution but most of the manganese was held in plant-available forms. Tests in the glasshouse showed that manganese sulphate or manganous oxide were likely to be the most effective seed-pellet additives, but manganese sulphate was harmful to sugar beet in slightly acid potting compost.Incorporating manganous oxide in the pellet prevented early symptoms of deficiency on sugar beet in field experiments and replaced an early foliar spray but the plants developed manganese deficiency later. The treatment was an economic and effective method of supplying manganese to sugar-beet seedlings too small to spray but, should manganese deficiency be prolonged, the plants will need spraying when large enough.  相似文献   

5.
YU  Q.; RENGEL  Z. 《Annals of botany》1999,83(2):175-182
The effect of copper (Cu), zinc (Zn) or manganese (Mn) deficiencyon the growth and activity of superoxide dismutase (SOD) formswas investigated in seedlings of narrow-leafed lupins (LupinusangustifoliusL.). Plants grown without Zn developed Zn deficiencysymptoms 24 d after sowing (DAS), and those grown without Mnshowed Mn deficiency symptoms 31 DAS. However, plants grownwithout Cu did not show visible leaf symptoms. Shoot dry weightwas decreased by Zn and Mn deficiency 24 DAS, and by Cu deficiency31 DAS. Soluble protein concentration was reduced considerablyby Zn deficiency 24 DAS, but was not affected by Cu deficiencyuntil 31 DAS. In contrast, soluble protein concentration inMn-deficient plants was higher than in control plants 31 DAS.Shoot concentration of micronutrients which were not suppliedto plants decreased significantly, with a simultaneous increasein concentration of one or more of the other nutrients analysed.The activities of total SOD, MnSOD and Cu/ZnSOD on a fresh weightbasis declined drastically in -Cu and -Zn plants 24 DAS. Onthe contrary, the activities of total SOD and Cu/ZnSOD on eithera fresh weight or soluble protein basis increased markedly in-Mn plants 24 DAS, and MnSOD activity increased significantlyin these plants 31 DAS. It was concluded that micronutrientdeficiency (Cu, Zn or Mn) altered the activities of SOD formsdepending on the kind and severity of the deficiency stress.Manipulation of the capacity of plants to tolerate oxidativestress may influence their capacity to tolerate micronutrientdeficiency.Copyright 1999 Annals of Botany Company. Copper,Lupinus angustifolius, manganese, deficiency, superoxide dismutase, zinc.  相似文献   

6.
Manganese is one of the essential microelements for plant growth, and cerium is a beneficial element for plant growth. However, whether manganese deficiency affects nitrogen metabolism of plants and cerium improves the nitrogen metabolism of plants by exposure to manganese-deficient media are still unclear. The main aim of the study was to determine the effects of manganese deficiency in nitrogen metabolism and the roles of cerium in the improvement of manganese-deficient effects in maize seedlings. Maize seedlings were cultivated in manganese present Meider's nutrient solution. They were subjected to manganese deficiency and to cerium chloride administered in the manganese-present and manganese-deficient media. Maize seedlings grown in the various media were measured for key enzyme activities involved in nitrogen metabolism, such as nitrate reductase, glutamate dehydrogenase, glutamine synthetase, and glutamic-oxaloace transaminase. We found that manganese deficiency restricted uptake and transport of NO(3)(-), inhibited activities of nitrogen-metabolism-related enzymes, such as nitrate reductase, glutamine synthetase, and glutamic-oxaloace transaminase, thus decreasing the synthesis of chlorophyll and soluble protein, and inhibited the growth of maize seedlings. Manganese deficiency promoted the activity of glutamate dehydrogenase and reduced the toxicity of excess ammonia to the plant, while added cerium relieved the damage to nitrogen metabolism caused by manganese deficiency in maize seedlings. However, cerium addition exerted positively to relieve the damage of nitrogen metabolism process in maize seedlings caused by exposure to manganese-deficient media.  相似文献   

7.
Summary Manganese oxide, produced byCorynebacterium sp. in liquid medium was found to be amorphous, probably hydrated and was readily reduced by neutral quinol. Preparations of the oxide had values of n in the formula MnOn which ranged from 1.76 to 1.88. The oxide was completely available to oats grown in sand culture but only slightly available in a manganese deficient soil. Plants grown under sterile conditions on agar slopes were able to obtain manganese from manganese oxide, indicating that the roots and not associated micro-organisms, were responsible for the solution process. Root washings of oat plants contained substances which dissolved manganese oxides and the activity of these substances increased with increasing acidity. The possible importance of these substances in making soil manganese available to plants is discussed.  相似文献   

8.
9.
Morphological characteristics of two Pedomicrobium-like budding bacteria are described. A structured surface layer was regularly observed on strain 868. Ruthenium red- and Alcian blue-staining polymers were found on both strains.When either strain was grown in the presence of iron or manganese, the corresponding oxides accumulated on their surfaces. In thin sections iron oxides appeared as fine threads, arrays of particles or dense coatings, depending on the source of iron. Manganese oxides appeared as branching filaments or convoluted ribbons. Both metal oxides stained with ruthenium red. Extraction of the oxides followed by ruthenium red staining revealed that polyanionic polymers previously deposited on the cells were associated with the metals.Treatment of cultures with glutaraldehyde, HgCl2, or heat, inhibited manganese but not iron deposition, suggesting that iron oxides accumulated by passive, non-biological processes. Manganese oxides apparently accumulated under control of a biological manganese-oxidizing factor. Incomplete inhibition of manganese deposition observed in cell suspensions suggested that, if the oxidizing factor was an enzyme, it was unusually stable.Based on these results, possible mechanisms of iron and manganese deposition in association with extracellular polymers are suggested.  相似文献   

10.
Else Boken 《Plant and Soil》1956,7(3):237-252
Summary Pot experiments with oats on manganese deficient sandy and moor soils, which are not deficient in iron, showed a steady increase in yield and manganese uptake by the plants with increasing additions of ferrous sulphate at four levels of manganese. Residual effects from ferrous sulphate application were not found either in the case of yields or manganese uptake by oats on a sandy soil.The effect observed following application of ferrous sulphate was due to a manganese effect. This is corroborated by the coincidence of the yield curves, showing the relationship between absorbed manganese and yield of dry matter, following the application of manganese sulphate and ferrous sulphate.Soils treated withM magnesium nitrate in the presence of equivalent quantities of either ferrous sulphate or hydroquinone yielded the same amounts of manganese. This result suggests that the manganese effect of ferrous sulphate is due to reduction of higher manganese oxides by ferrous sulphate.  相似文献   

11.
锰有效性对大豆锰、铁和磷吸收及其分布的影响   总被引:1,自引:0,他引:1  
本文研究外源锰有效性对大豆生长和锰、铁、磷吸收及其分布影响的结果表明,在锰缺乏和锰浓度超过50μmol·L-1的处理条件下,大豆生长受到明显抑制。随着外源锰浓度增加,大豆体内,尤其在老叶中锰浓度显著增加。锰和铁之间存在一定的拮抗作用。缺锰和锰毒不影响大豆对磷的吸收。但是,缺锰显著影响磷在老叶和新叶中的分配。  相似文献   

12.
Summary The manganese content of sugar beet grown in pots of organic soils taken from fields where crops regularly show symptoms of manganese deficiency, and the effects on it of foliar sprays of manganous sulphate and of manganous oxide or manganese silicate frit applied to the soil, of changing the soil pH, air-drying the soil, and growing the plants either in the glasshouse or outside were determined. All the manganese treatments increased the concentration of manganese in the plants and decreased deficiency symptoms, but increased the dry matter yield only slightly. Increasing the pH by liming greatly increased symptoms and decreased the manganese concentration in the dry matter; air-drying the soil before cropping had the opposite effect. Plants grown in pots of the same soil in the glasshouse or outdoors showed similar symptoms and had similar manganese content.The concentration of manganese in the leaves was related to the percentage of plants with deficiency symptoms and to the concentration of active soil manganese. Leaves usually had symptoms when the concentration of manganese in the dried leaves was less than 30 ppm, and always had severe symptoms when they contained less than 15 ppm Mn. The soil analyses suggest that sugar beet grown in organic soil with pH greater than 7.0 and containing less than 40 ppm active soil manganese is likely to show deficiency symptoms.  相似文献   

13.
The effects of manganese supply on plant growth and on photosynthesisand manganese concentrations in young leaves were examined inSeaton Park subterranean clover in three glasshouse water cultureexperiments. Plants werc grown initially with a copious supply of manganese,and transferred to solutions either with or without manganese.Sequential harvests were taken to determine the effects of developingmanganese deficiency on dry matter (DM) yield of whole plantsand selected characteristics [manganese, chlorophyll and photosyntheticoxygen evolution (POE)] of youngest open leaf blades (YOL).In addition, the deffect of leaf age and iron supply on POEwerc examined. Manganese concentrations and POE in YOL declined markedly andrapidly in plants transferred to solutions without manganese,while chlorophyll concentrations of YOL and plant DM yield respondedmore weakly and more slowly. As a result, a level of manganesedeficiency which depressed POE in young leaves by more than50 per cent had no effed on DM production. In youngleaves (YOL, YOL + 1, YOL–1), POE declined whentheir manganese concentrations were < 20 µg g–1DM. Iron supply did not affect this rdationship. When learnwith < 20 µg Mn g–1 DM were detached and incubatedfor 24 h in solutions containing high concentrations of manganese,their POE increased to normal rates; leaves with higher manganeseconcentrations did not respond. It is suggested that the valueof 20 µg Mn g–1 DM is the functional manganese requirementfor POE in young subterranean clover leaves It is also suggestedthat this value may be used as a critical value for indicatingmanganese deficiency in subterranean clover. Functional nutrient requirements determined in this way by correlationof nutrient concentrations in young leaves with their biochemicalor physiological activities appear to offer more accurate andconsistent standards for use an critical values for diagnosisof plant nutrient status than do the critical values determinedin the usual way by correlation with plant dry weight. Trifolium subterraneum L. subterranean clover, manganese, functional requirements, deficiency diagnosis, nutrient requirements, critical values, photosynthetic oxygen evolution  相似文献   

14.
Studies on the manganese of the chloroplast   总被引:9,自引:5,他引:4       下载免费PDF全文
Homann PH 《Plant physiology》1967,42(7):997-1007
Manganese deficiency of green plants is known to affect preferentially the activity of the oxygen evolving system in the photosynthetic apparatus. Our studies showed that the time needed to reactivate photosynthesis in Mn-deficient algae varies with each culture, and is often very short when Mn is added not before illumination but during the light period. The recent finding by Cheniae and Martin that the reactivation requires light, is confirmed. The plain incorporation of 54Mn into deficient algae as distinguished from reactivation was barely affected by light, yet was inhibited by uncouplers of phosphorylation. Higher plants responded to manganese deficiency either by adjusting the number of chloroplasts per cell to the limited Mn supply, or by forming disorganized chloroplasts with low chlorophyll content. These 2 types of responses produced chlorotic plants which had either a few photosynthetically active or many disabled chloroplasts. Photosystem I mediated photophosphorylation turned out to be much more sensitive to manganese deficiency than the system I dependent photoreduction of NADP+.  相似文献   

15.
SINGLE  W. V. 《Annals of botany》1958,22(4):479-488
The distribution of manganese in wheat plants grown in solutionculture has been studied. Manganese supply from the medium wasso arranged that early leaves received sufficient for normalfunction but subsequent growth was severely restricted by deficiencyof the element. Under these conditions little or no redistributionwithin the plant was observed, so that the early leaves retainedmost or all of their manganese, and remained healthy. When manganesewas applied externally to the second leaves of deficient plantsa small but significant amount was translocated to the growingpoints. The effect was slightly enhanced by repeated rewettingof the treated leaves, but the amount moved was still smallin relation to that applied and to the requirement of the plants.It appears that manganese is not readily transported by thephloem under these conditions, but this does not wholly accountfor the ability of some leaves to retain critical levels whena state of deficiency exists at the growing points. Possiblemechanisms for this effect are discussed.  相似文献   

16.

Micrometer sized stromatolitic structures called Frutexites are features observed in samples from the deep subsurface, and hot-spring environments. These structures are comprised of fine laminations, columnar morphology, and commonly consist of iron oxides, manganese oxides, and/or carbonates. Although a biological origin is commonly invoked, few reports have shown direct evidence of their association with microbial activity. Here, we report for the first time the occurrence of subsurface manganese-dominated Frutexites preserved within carbonate veins in ultramafic rocks. To determine the biogenicity of these putative biosignatures, we analyzed their chemical and isotopic composition using Raman spectroscopy and secondary ion mass spectroscopy (SIMS). These structures were found to contain macromolecular carbon signal and have a depleted 13C/12C carbon isotopic composition of – 35.4?±?0.50‰ relative to the entombing carbonate matrix. These observations are consistent with a biological origin for the observed Frutexites structures.

  相似文献   

17.
Summary Soybean (Glycine max (L) Merr. cv. Bragg) seedlings were grown in nutrient solutions to evaluate the response to manganese nutrition as affected by potassium supply. In solutions containing 275 M manganese, increasing the solution concentration of potassium from 1 mM to 10 mM alleviated symptoms of manganese toxicity, decreased manganese concentrations in the leaves and increased dry matter yields of the plants. The reduction in manganese toxicity was brought about by a reduced rate of root absorption of manganese at high potassium supply levels.Increasing the supply of either potassium or manganese decreased the leaf concentration of magnesium although there were no apparent symptoms of magnesium deficiency in any treatment. The reduced concentration of magnesium in the leaves was due to effects of potassium and manganese on the rate of root absorption of magnesium.Under manganese deficiency conditions, growth was reduced and manganese concentrations in plant parts were very low; there was no effect of potassium supply when manganese was absent from the nutrient solution.  相似文献   

18.
Cooper , Eugene E., and Raymond E. Girton . (Purdue U., Lafayette, Ind.) Physiological effects of manganese deficiency related to age in soybeans (Glycine max). Amer. Jour. Bot. 50(2): 105–110. Illus. 1963.—Soybean plants when grown in manganese-deficient silica sand cultures developed typical manganese deficiency symptoms of interveinal chlorosis and necrosis. Physiological effects including depression of photosynthesis, respiration, growth, and relative chlorophyll contents were studied. The depression of photosynthesis was not always proportional to reduced chlorophyll content. This is taken to indicate the importance of manganese in reactions concerned in photosynthesis in addition to chlorophyll formation. Age of leaves related to position on the plant and actual aging of the plants with time sometimes produced different results when related to photosynthetic rates, which mainly decreased with age of plants. Chlorophyll content in young leaves increased with plant age, except for a consistent decrease after leaf maturity. Respiration rates generally decreased with age. For the most part, the effects of aging on photosynthesis, respiration, and chlorophyll contents were the same for soybeans as for other species reported in the literature.  相似文献   

19.
Zhao  Guoyan  Cheng  Junhui  Sun  Ningning  Ma  Changle  Dai  Meixue 《Plant and Soil》2019,438(1-2):223-237
Plant and Soil - Wetlands play vital roles as sinks for metal contaminants. Some wetland plants accumulate manganese (Mn) oxides in the black biofilm around roots and rhizomes, although the...  相似文献   

20.
A number of pot experiments were made on various crops, to study the effects on the chemical composition of the plants of treating the soil with cobalt, copper or nickel sulphates, or with the cupric or ferric salts of ethylenediamine-tetraacetic acid (EDTA).
The tops of copper sulphate-treated plants usually contained higher concentrations of copper, manganese, calcium and magnesium and lower concentrations of potassium and phosphorus, than those of control plants.
The most marked effect of cobalt on oat was to increase the concentration of Ca+Mg in the tops; nickel had a profound effect on the composition of barley tops.
Total iron concentration was reduced in oat by cobalt and copper, and in barley by copper and nickel application. Symptoms of iron deficiency appeared only in the oat plants, their incidence being correlated with the reduction in iron concentration in the tops.
The ferric salt of EDTA tended to reduce the incidence of iron deficiency symptoms produced in oat by copper sulphate, but also gave rise to distinct toxic effects. Plants given the cupric salt of EDTA contained unusually large amounts of iron.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号