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1.
The ability of selenium (Se) to counteract salt inhibitory effects in crop plants, especially in tomato, is still poorly documented. In order to examine the impact of Se addition on the growth, some biochemical parameters related to osmotic adjustment and antioxidant defense of salt-stressed tomato, a two-factorial experiment was conducted in a greenhouse. The plants were supplied with NaCl (0, 25, or 50 mM) and Se (0, 5, or 10 μM), individually or simultaneously. The results showed that salinity had a deleterious impact on plant biomass and physiological parameters studied. The application of Se alleviated this adverse effect by improving the integrity of cell membranes and by increasing leaf relative water content under stress conditions. Moreover, the application of 10 μM Se significantly increased the photosynthetic pigments concentration under salt stress. Salt stress also caused an inhibition of catalase activity, but its activity was restored in the presence of Se. The free radical scavenging activity significantly increased in plants subjected to 25 mM NaCl and supplied with 5 µM Se, compared to NaCl-alone treatment. Both physiological and biochemical results indicate that 10 µM Se treatment can increase plant performance under salt stress, especially under high NaCl concentration.

Abbreviations: CAT: catalase; Chl: chlorophyll; DPPH: 2,2-diphenyl-1-picrylhydrazyl; DW: dry weight; FW: fresh weight; POD: peroxidase; REL: relative electrolyte leakage; RWC: relative water content; free radical scavenging activity (FRSA); TW: turgid weight  相似文献   


2.
Selenium (Se) is an essential element for humans but is not considered as essential for plants. However, its beneficial role in improving plant growth and stress tolerances is well established. In order to study the role of Se in cadmium (Cd) toxicity in pepper (Capsicum frutescens cv. Suryankhi Cluster), this experiment was carried out in greenhouse conditions. Treatments comprised Cd [0, 0.25, and 0.5 mM cadmium chloride (CdCl2)] and Se [0, 3, and 7 µM sodium selenite (Na2SeO3)] with three replications. The result showed that Cd decreased chlorophyll a, chlorophyll b, and carotenoids, whereas Se supplementation diminished Cd toxicity on photosynthetic pigment. Selenium at 7 µM significantly increased the leaf area in the plants grown at 0.25 mM Cd. The application of Se at 3 µM with 0.25 mM Cd and Se at 3 µM and Se at 7 µM with 0.5 mM Cd increased the activity of catalase (CAT). Selenium at 7 µM decreased the proline content of pepper leaves exposed to Cd at 0.5 mM (30%). Selenium significantly enhanced the antioxidant activity of leaves, which was diminished by Cd toxicity. In general, Se has a beneficial effect on plant growth and is an antioxidant enzyme of pepper cv. Suryankhi Cluster under Cd stress and non-stress conditions.  相似文献   

3.
The objective of this work was to study the effect of root and foliar application of two commercial products containing amino acids from plant and animal origin on iron (Fe) nutrition of tomato seedlings cultivated in two nutrient media: lime and normal nutrient solutions. In the foliar‐application experiment, each product was sprayed with 0.5 and 0.7 mL L–1 2, 7, 12, and 17 d after transplanting. In the root application experiment, 0.1 and 0.2 mL L–1 of amino acids products were added to the nutrient solutions. In both experiments, untreated control plants were included as well. Foliar and root application of the product containing amino acids from animal origin caused severe plant‐growth depression and nonpositive effects on Fe nutrition were found. In contrast, the application of the product from plant origin stimulated plant growth. Furthermore, significantly enhanced root and leaf FeIII‐chelate reductase activity, chlorophyll concentration, leaf Fe concentration, and FeII : Fe ratio were found in tomato seedlings treated with the product from plant origin, especially when the amino acids were directly applied to the roots. These effects were more evident in plants developed under lime‐induced Fe deficiency. The positive results on Fe uptake may be related to the action of glutamic acid, the most abundant amino acid in the formulation of the product from plant origin.  相似文献   

4.
硒对大蒜生理特性、含硒量及品质的影响   总被引:7,自引:2,他引:7  
以金蒜3号为试材,采用盆栽试验,通过叶面喷施不同浓度、不同次数的亚硒酸钠研究了硒对大蒜生理特性、含硒量和品质的影响。结果表明:在生长期4月5日、15日和25日累计喷施1次、2次、3次3个浓度(5、10、15 mg/L)的亚硒酸钠溶液,均不同程度影响大蒜生理特性、含硒量和品质。与对照相比,叶面喷施2次10 mg/L的亚硒酸钠溶液,可显著提高叶片中光合色素含量和光合性能;能显著改善蒜薹和鳞茎品质,单薹鲜质量和单头鲜质量分别提高68.25%和29.00%,可溶性糖、可溶性蛋白、维生素C含量分别提高73.05%、104.66%、18.95%和82.01%、51.27%、69.82%;并可有效提高鳞茎中游离氨基酸含量(38.91%),降低蒜薹中游离氨基酸含量(36.95%);同时可降低蒜薹和鳞茎中大蒜素含量,但差异不显著。蒜薹和鳞茎硒含量随硒浓度和喷施次数的增加而显著提高,最高可达19.81和23.96 mg/kg,为对照的3.85和4.41倍。综合各因素指标,大蒜以叶面喷施2次10 mg/L的亚硒酸钠为宜。  相似文献   

5.
施用硒矿粉对烟苗光合特性、成苗素质及硒积累的影响   总被引:1,自引:0,他引:1  
通过在营养液中加入硒矿粉的方法,研究了不同硒矿粉用量对烟苗光合特性、成苗素质及硒积累的影响。结果表明,苗期施用硒矿粉能促进烟苗生长,随着施用量的增加,烟苗的叶绿素、可溶性糖、根系活力和硒含量明显增加。低用量的硒矿粉提高了烟苗的净光合速率(Pn),可能增加了叶绿素含量和减少了气孔限制是重要原因;高用量的硒矿粉导致烟苗Pn下降,主要是由气孔因素决定的。在本试验条件下,适宜的苗期硒矿粉用量为24.6 kg/hm2。  相似文献   

6.
低温弱光对番茄植株生长发育及生理功能的影响   总被引:19,自引:1,他引:19  
低温弱光(60μmol/m~2·s、10℃/10℃和5℃/5℃)胁迫下番茄植株生长势、根系活力、叶片净光合作用完全被抑制,株高、叶片数增长受阻,与低温弱光处理前相比,植株地上部干物质量下降,但根系干物质量并未下降。在恢复过程中10℃处理植株根系活力、光合作用及生长发育迅速得到恢复,而5℃处理植株除成熟叶光合作用可迅速恢复外其他指标恢复均较缓慢。  相似文献   

7.
施纳米硒对小麦籽粒硒含量及其品质性状的影响   总被引:6,自引:0,他引:6  
【目的】研究基施纳米硒肥对不同小麦品种籽粒百粒重、硒含量、硒形态,其他矿质元素以及面粉糊化特性的影响,为利用纳米硒肥进行小麦硒生物强化提供参考。 【方法】选择 110 份小麦品种 (系),在扬州大学农学院网室种植,采用的施肥方式为基施纳米硒肥,设每千克土施 Se 0 (CK)、100 (Se100)、150 (Se150) mg 2 次重复,随机区组设计。小麦成熟期收获籽粒,测定百粒重。利用离子发射光谱 – 原子吸收仪测定了籽粒 Se、Ca、Mg、Cu、Fe、Mn、Zn 及 S 含量。选择高硒处理中硒含量前 10 名的品种,利用 LC-UV-AFS 测定了籽粒中不同形态硒的含量。随机挑选 59 个品种并利用 RVA 仪 (快速粘度分析仪) 测定其面粉糊化特性的特征值。利用 MATLAB 和 SPSS 软件进行数据分析。 【结果】基施硒 0、100、150 mg/kg 土,小麦籽粒的百粒重均值分别为 3.78、4.11 和 3.70 g,籽粒中总硒含量分别为 2.00、12.46 和 17.35 mg/kg。籽粒中的硒主要以有机态形式存在,以硒蛋氨酸含量最多,其次是硒甲基化半胱氨酸和少量的硒半胱氨酸,无机态硒仅微量存在于极少数品种中。基施硒肥对测定的矿质元素的吸收积累既有协同也有拮抗作用,对小麦面粉的糊化特性没有显著影响。糊化特性取决于基因型,不同品种间存在极显著差异。 【结论】硒肥可以提高小麦籽粒中的硒含量,但增幅因品种而异;硒强化后籽粒中硒主要以有机态形式存在;低浓度硒处理可以提高小麦籽粒的百粒重,且不会影响小麦的面粉糊化特性。  相似文献   

8.
Soil hydric availability and nitrogen fertilization are important environmental factors that influence sugarcane production. In the present study, the physiological attributes SPAD index, maximum photochemical efficiency of photosystem II (Fv/Fm), leaf area index (LAI), chlorophyll and carotenoid content, and sugarcane productivity were assessed under different nitrogen doses (0, 50, 100, 150, and 200 kg N ha?1) applied in the form of urea via subsurface drip fertigation. The physiological attributes were determined 38, 121, 208, 291, and 381 days after the third harvest (DAH), and stalk and sugar productivity at 381 DAH. The 100 kg N ha?1 dose has produced better results for the sugarcane physiological attributes. Increasing doses of nitrogen applied via subsurface drip fertigation increased the productivity of stalks and sugar considerably.  相似文献   

9.
控释氮肥对水稻秧苗形态特征和生理特性的影响   总被引:8,自引:0,他引:8  
通过种肥接触水稻育苗试验,比较秧苗叶片中几种酶活性和激素含量,探明接触性施肥提高肥料利用率的效应和机理,以确定控释肥在水稻育苗上的最佳施用量和施用方法。研究结果表明,水稻种子与大量控释氮肥接触的条件下仍能安全萌发,且用量为800 g/盘和1000 g/盘时能够明显促进水稻秧苗的生长发育;在同等施肥量的条件下,肥料在种子下方接触施用的方法最有利于秧苗的生长;控释氮肥用量为800 g/盘和1000 g/盘时,秧苗叶片中的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸-过氧化物酶(AsA-POD)活性高于常规尿素处理,而丙二醛(MDA)含量则低于常规尿素处理,这有利于促进水稻秧苗的生长;控释氮肥用量为1200 g/盘时,会导致叶片内的SOD、CAT和AsA-POD活性明显降低和MDA含量的相对增加;随控释氮肥用量的增加,秧苗叶片生长素(IAA)逐渐增加,但当达到1200 g/盘时,IAA含量突然增加;另外,氮素缺乏和过多都会诱导秧苗体内脱落酸(ABA)含量明显增加而不利于秧苗正常生长。  相似文献   

10.
Vermicompost can play an effective role in plant growth and development and also in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances and plant growth regulators and also high levels of macro and micro nutrients. The aim of this study was to investigate the effects of vermicompost and salinity interactions on some morphological and physiological features and concentration of mineral elements of bean (Phaseolus vulgaris L. cv. Light Red Kidney) cultivar. A factorial experimental with five different volumetric ratios of vermicompost and sand, including to: 0:100; 10:90; 25:75; 50:50 and 75:25 and four levels of salinity [20, 40, 60 and 80 mmol l?1 sodium chloride (NaCl)], and control was conducted base on Randomized Complete Block Design with three replications. Bean seeds were sowed in plastic pots, the seedlings being sampled 42 days old (flowering stage).The results showed that vermicompost had significant effect on all studied traits under stress and non-stress (p ≤ 0.05).In this experiment, the vermicompost significantly increased the photosynthetic rate and concentrations of potassium (K+) and calcium (Ca2)+in leaf and root tissues. In salinity levels of 20, 40 and 60 mmol l?1NaCl, all subjected ratios of vermicompost and in 80 mmol l?1NaCl the ratios of 10% and 75% vermicompost, significantly ameliorated negative effects of salinity. In both stress and non-stress conditions, using 10% volume of vermicompost is recommended to improve the growth of bean plants.  相似文献   

11.
12.
Abstract

Enrichment of soils with organic amendments could increase the content of available nutrients, improve soil chemical characteristics and increase plant growth. In the current pots experiment, the influences of biochar (BC), humic acid (HA), and compost (CO) on barely growth were investigated under saline conditions. Barely plants grown on a clay loam soil and irrigated with saline water concentration of (EC?=?13.8 dS m?1) were amended with BC, HA and CO at a rate of 1 or 3% of soil weight. The results showed that BC, HA and CO treatments had significant effects on the soil salinity, pH, organic matter (SOM), and plant nutrients. The results showed that the high rate application of BC, HA and CO increased the SOM by 14, 75 and 58% respectively, above the control. Consequently, the total chlorophyll as affected by the treatments can be arranged in descending order: BC3 > CO1 > CO3 > HA3 > HA1 > BC1 > C. The high rates of BC, HA and CO increased the dry biomass by 28.0, 21.6 and 39.7% respectively, above the control %, respectively, above the control. The investigated organic amendments increased the nutrients availability and uptake and enhanced the synthesis of chlorophyll in the plant tissues and this may be the reason of increasing the ability of barley to tolerate salinity.  相似文献   

13.
硒是植物非必需营养元素,但是适量的硒对植物生长有着促进作用。通过研究硒对水稻光合作用及抗氧化作用的影响为硒对水稻生长的促进作用提供依据。采用盆栽试验,研究不同施硒浓度(0~5 mg/kg)对水稻产量、硒含量、叶绿素含量、光合参数、抗氧化酶活性及细胞膜透性的影响。结果表明,施硒显著提高了水稻产量,在1.0和5.0 mg/kg施硒水平较对照(不施硒)分别增产20.8%和28.8%。施硒提高了水稻谷壳、大米、秸秆及根中硒的含量。施硒对水稻叶绿素a和叶绿素b含量影响不大,但在5.0 mg/kg施硒水平上显著增加了水稻类胡萝卜素含量。施硒显著增加了叶片胞间二氧化碳浓度、蒸腾速率和光合速率,最高增幅分别为28.4%、26.1%及25.0%。施硒显著降低了水稻叶片离子渗漏量及相对电导膜透性。施硒显著增加了超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)的活性,最高增幅分别为101.2%、23.4%和64.3%。试验结果表明,硒能增强水稻的光合作用及抗氧化作用,从而达到了促进水稻生长的效果。  相似文献   

14.
施硒对茄子吸收转化硒和品质的影响   总被引:16,自引:4,他引:16  
盆栽试验结果表明,土壤施硒(0.15、0.60、3.00mg/kg)条件下,茄子的含硒量随施硒量的增加而显著增加。当施硒量为0.60和3.00mg/kg时,茄子无机硒转化成有机硒的比率下降,显著提高了茄子粗蛋白、粗脂肪和还原糖含量,增加了茄子的必需氨基酸总量,改善了茄子的品质。土壤施硒显著增加了茄子蛋氨酸、胱氨酸和丝氨酸的含量,但谷氨酸和脯氨酸的含量显著降低。  相似文献   

15.
【目的】 以穴盘育苗番茄为试材,研究分析了Bacillus amyloliquefaciens Pb-4对植物的促生作用及应用潜力,为该菌在番茄穴盘育苗上的应用提供理论依据。 【方法】 采用穴盘育苗的方法,以Bacillus amyloliquefaciens Pb-4在PYJ培养基中培养48 h的发酵液为接种剂,设置不接种 (CK) 和接种20 (T20)、60 (T60)、100 (T100) 和200 (T200) mL/L 基质5个处理,番茄幼苗四叶一心时取样分析其生理指标。 【结果】 1) Pb-4显著促进了番茄幼苗地上部的生长,其中T100处理的促生作用最强,株高、茎粗、叶面积以及地上部干重较CK处理显著增加了28.5%、23.9%、57.4%和42.4%,而T200处理的促生作用下降;Pb-4促进了番茄幼苗根系的生长,显著增加了根系直径大于0.5 mm的根长占总根长的比重,T20处理的根表面积和根体积最大,较CK处理显著增加了16.9%和34.2%,但与T100处理间差异不显著。2) Pb-4显著增加了番茄幼苗光合色素含量,其中T100处理的总叶绿素含量最高,CK处理最低,T20、T60、T100和T200处理分别较CK处理增加5.8%、9.4%、12.6%和7.6%;Pb-4提高了番茄幼苗茎、叶中IAA和GA3的含量,而对根中IAA和GA3的含量没有影响。3) 相关性分析表明,番茄株高、茎粗、叶面积、地上部干重与叶片光合色素含量、茎中IAA、GA3以及叶片中GA3的含量显著相关,而根系干重与光合色素含量、茎中IAA含量显著相关,根表面积与叶片IAA以及根系中GA3的含量显著相关,根体积与叶片中IAA含量显著相关。 【结论】 Bacillus amyloliquefaciens Pb-4可促进番茄幼苗地上部生长,改变根系形态特征,提高番茄叶片光合色素以及不同器官中IAA和GA3含量,其对番茄幼苗的促生作用在施用量为100 mL/L基质时最佳,超过该施用量促生作用降低。   相似文献   

16.
Considering the importance of onion and its cultivation in saline soils, a two-year experiment was carried out to investigate the effects of soil applied zeolite and foliar application of selenium (Se) and silicon (Si) on onion yield, qualitative traits and physiological attributes, under salinity stress. An experiment was performed at three-way factorial design with three replications as follows: zeolite at three levels (0, 4 and 8 ton ha-1), Se at three levels (0, 0.5 and 1 kg ha-1) and Si at three levels (0, 200 and 400 kg ha-1). The results indicated that the effect of year was significant on all studied traits except for soluble solids, bulb nitrogen, leaf sodium and potassium, chlorophyll content and peroxidase activity. Number of small-sized bulbs decreased with increasing zeolite, Se and Si application. Dry matter, soluble solids, nitrogen content, nitrate concentration as well as protein content significantly increased due to zeolite, Se and Si application. Leaf sodium content and enzyme activity decreased due to zeolite, Se and Si application. Overall, 8 ton ha-1 zeolite along with 1 kg ha-1 Se and 400 kg ha-1 Si caused the maximum onion yield and qualitative and physiologic traits including soluble solids, potassium, protein, chlorophyll and photosynthesis .  相似文献   

17.
In order to study the effects of biofertilizers and cycocel on some physiological and biochemical characteristics of wheat (Triticum aestivum L.) under salinity condition, a factorial experiment was conducted based on randomized complete block design with three replications under greenhouse condition in 2015. Treatments were included salinity in four levels [no salt (control or S0), salinity 30 (S1), 60 (S2) and 90 (S3) mM NaCl equivalent of 2.76, 5.53 and 8.3 dS m?1, respectively], four biofertilizers levels [no biofertilizer (F0), seed inoculation by Azotobacter chrocoocum strain 5 (F1), Pseudomonas putida strain 186 (F2), both inoculation Azotobacter + Pseudomonas (F3)] and three cycocel levels [without cycocel as control (C0), application of 600 (C1) and 1000 (C2) mg L?1]. Results showed that salinity severe stress (90 mM) decreased chlorophyll content, relative water content (RWC), total chlorophyll, photochemical efficiency of PSII and yield of wheat. Whereas, soluble sugars and proline content, electrical conductivity (EC), the activity of catalase (CAT), peroxidase (POD), polyphenol oxidase (PPO) enzymes were increased. Similar results were observed in CAT, POD and PPO activities due to inoculation by biofertilizers and cycocel. Salinity at 30 mM increased the photochemical efficiency of PSII and chlorophyll content in plants grown under biofertilizer and cycocel treatment but with increasing salinity up to 90 mM mentioned parameters were decreased. The highest proline and soluble carbohydrate at all salinity levels were observed in plants treated in the highest cycocel level and Azotobacter+ Pseudomonas application. Generally, it was concluded that biofertilizers and cycocel can be used as a proper tool for increasing wheat yield under salinity condition.  相似文献   

18.
Phytotoxicity due to copper (Cu) is generally associated with visible symptoms such as a decrease in plant shoot and root growth and chlorosis. The application of low levels of Cu or plant exposure to the metal for short periods can affect several cell processes, involving changes in the levels of metabolites related to the plant antioxidative response. The purpose of this study was to compare the response of the reduced and oxidized glutathione system and Cu uptake in tomato plants exposed to phytotoxic levels of Cu in hydroponic culture. Attention was centered on establishing whether determination of the levels of both peptides in plants exposed for a short period of time (acute treatment) compared with exposure for an extended period (chronic treatment) could be used as an early indicator of Cu stress in tomato plants. For the acute treatment, the plants were exposed to 0.4, 9, and 36 μM Cu for 48 h, and for the chronic treatment to 0.4, 3, and 12 μM Cu for 28 d. Results indicate that plants subjected to the chronic treatment showed toxicity symptoms, among them chlorosis and a drastic decrease of the aerial part and root biomass, an effect that was not observed in the plants subjected to the acute treatment. Moreover, Cu applied to the plant, either in the acute or in the chronic treatment, modified the levels of reduced and oxidized glutathione in shoots and roots. The most noticeable effect was observed on the concentration of reduced glutathione in roots, where the concentration of this peptide decreased as the Cu concentration increased, and this effect was independent of the morphological changes undergone by the root and of the time of Cu application. The similarity of the responses to the acute and the chronic treatments indicates that assessment of the redox state of glutathione in the roots of plants exposed to copper, especially the change in levels of reduced glutathione, may represent a good indicator of the early plant response to stress due to excessive Cu supply.  相似文献   

19.
硒对苦荞硒、总黄酮和芦丁含量、分布与累积的影响   总被引:6,自引:0,他引:6  
采用盆栽试验探讨土壤施硒对苦荞硒、总黄酮和芦丁含量、分布与累积的影响。结果看出,在土壤施硒0.5~2.0 mg/kg范围,苦荞根在苗期(40 d)大量吸收并累积硒,全生育期各器官硒含量极显著提高;在生长中后期(60~80 d) 硒的累积最快,累积量最多。硒在苦荞各器官中的分布为:在40 d时,根>叶>茎;60 d时Se0.0处理为叶>根>花>茎,施硒各处理则为花>根>叶>茎;80 d时Se0.0处理以花>根>叶>茎>子粒,Se0.5处理以花>叶>子粒>茎>根,施硒≥1.0 mg/kg的处理则为花>叶>茎>根>子粒。土壤施硒≤1.0 mg/kg促进苦荞生长,提高地上部各器官干重和植株总干重以及各器官总黄酮和芦丁含量与累积量,不改变总黄酮和芦丁的器官分布,增加苦荞中后期对总黄酮的累积;以Se0.5处理效应最佳,各差异达显著水平。过量的硒(Se1.5~2.0 mg/kg)显著抑制苦荞生长,降低各器官干重、总黄酮和芦丁含量与累积,不利于硒在子粒中富集和总黄酮在子粒中分布。表明在低硒土壤上栽培苦荞,土壤施硒以不超过1.0 mg/kg为宜,既能最大限度的提高苦荞各器官硒、总黄酮和芦丁含量和累积量,又可降低施用硒肥的成本和减少硒肥对环境的影响。  相似文献   

20.
硒、钴对苜蓿青干草营养水平影响的研究   总被引:1,自引:0,他引:1  
通过在苜蓿草地上基施硒、钴物料的田间试验,研究苜蓿对硒钴的吸收、积累和转化特点,以及各种物料对苜蓿青干草中营养成分和微量元素含量的影响。结果表明: (1)硒或钴物料均能提高苜蓿青干草中硒的含量,物料中硒含量越高,青干草中硒的含量也越高。钴能显著提高苜蓿青干草中的钴含量,过量施钴会造成钴料的浪费。虽然硒对草中钴积累量影响不大,但硒钴混合物料可显著提高牧草钴的积累量,物料中硒含量越高草中钴的积累量越多。(2)硒钴的合理混施能显著提高苜蓿对硒、钴的利用率以及物料中无机硒向牧草中有机硒的转化率,提高牧草中硒的有效性和安全性。(3)在所有硒、钴物料中,高硒低钴能提高苜蓿青干草的粗蛋白和粗脂肪含量,对粗纤维和无氮浸出物影响不大。而其他硒、钴物料均能显著提高苜蓿干草中的粗纤维含量,降低粗脂肪含量,对粗蛋白和无氮浸出物含量影响不大。(4)硒钴混合物料能显著提高苜蓿青干草中Mo、Cu、B、Fe、Mn、Zn 6种元素的含量,其中Mo的提高幅度最大为142.34 %~256.45 %, 其次为Fe、Mn和Zn,提高幅度分别为48.16 %~59.45 %、32.88 %~41.66 %和37.10 %~96.39 %。Cu和B的提高幅度最小,分别为13.43 %~37.33 %和14.60 %~39.67 %。  相似文献   

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