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Subconjunctival trypsin injection for anterior chamber fibrin exudates in eyes with globe rupture following vitrectomy
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作者 Shu-Wen Lu Hao-Yu Li +3 位作者 Xin-Min Li Chao Ma Xian Li Qiu-Ming Hu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第11期2037-2044,共8页
AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repai... AIM:To compare the safety and clinical outcomes of subconjunctival trypsin and dexamethasone(DEX)injections in the treatment of anterior chamber fibrin exudates in eyes with globe rupture following primary wound repair and vitrectomy.METHODS:A retrospective analysis included 42 males and 10 females(mean age 46.0±6.0y,range 34 to 58y)who underwent primary wound sutures and vitrectomy for globe rupture.Patients with pupil-covered fibrinous exudate or/and membrane in the anterior chamber were treated.On the first postoperative day,subconjunctival injections of either 5000 units(0.4 mL)of trypsin solution(n=25)or 0.5 mL(1 mg)DEX(n=27)were administered to accelerate exudate absorption.Efficacy was assessed by observing break time and partial absorption of the fibrin exudate membrane.Safety and comfort were evaluated by monitoring intraocular pressure(IOP),allergy,pain,and foreign body sensation.RESULTS:Both groups achieved 1/3 absorption of the anterior chamber fibrin exudate membrane,but the trypsin group exhibited shorter break time and partial absorption time compared to the DEX group(P<0.05).Trypsin treatment was also less irritating to patients.No adverse reactions were reported,and IOP remained stable.Visual acuity improved in both groups without statistical difference.CONCLUSION:Compared to DEX,trypsin demonstrates a shorter absorption time for the fibrin exudate membrane with a more comfortable process in treating pupil-covered fibrinous exudate or/and membrane after vitrectomy for globe rupture. 展开更多
关键词 globe rupture VITRECTOMY exudative fibrin membrane TRYPSIN dexamethasone
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A Novel Soft Clustering Method for Detection of Exudates
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作者 Kittipol Wisaeng 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期1039-1058,共20页
One of the earliest indications of diabetes consequence is Diabetic Retinopathy(DR),the main contributor to blindness worldwide.Recent studies have proposed that Exudates(EXs)are the hallmark of DR severity.The presen... One of the earliest indications of diabetes consequence is Diabetic Retinopathy(DR),the main contributor to blindness worldwide.Recent studies have proposed that Exudates(EXs)are the hallmark of DR severity.The present study aims to accurately and automatically detect EXs that are difficult to detect in retinal images in the early stages.An improved Fusion of Histogram-Based Fuzzy C-Means Clustering(FHBFCM)by a New Weight Assignment Scheme(NWAS)and a set of four selected features from stages of pre-processing to evolve the detection method is proposed.The features of DR train the optimal parameter of FHBFCM for detecting EXs diseases through a stepwise enhancement method through the coarse segmentation stage.The histogram-based is applied to find the color intensity in each pixel and performed to accomplish Red,Green,and Blue(RGB)color information.This RGB color information is used as the initial cluster centers for creating the appropriate region and generating the homogeneous regions by Fuzzy C-Means(FCM).Afterward,the best expression of NWAS is used for the delicate detection stage.According to the experiment results,the proposed method successfully detects EXs on the retinal image datasets of DiaretDB0(Standard Diabetic Retinopathy Database Calibration level 0),DiaretDB1(Standard Diabetic Retinopathy Database Calibration level 1),and STARE(Structured Analysis of the Retina)with accuracy values of 96.12%,97.20%,and 93.22%,respectively.As a result,this study proposes a new approach for the early detection of EXs with competitive accuracy and the ability to outperform existing methods by improving the detection quality and perhaps significantly reducing the segmentation of false positives. 展开更多
关键词 Diabetic retinopathy retinal images histogram-based fuzzy C-means clustering exudateS
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Preliminary Study on Garlic Root Exudates Influences to the Growth of Pomegranate Wilt Pathogen(Ceratocystis fimbriata)and Bacillus subtilis 被引量:5
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作者 汤东生 王斌 +1 位作者 毛忠顺 何霞红 《Agricultural Science & Technology》 CAS 2011年第2期237-240,共4页
[Objectives] This paper aims to explore the possibility to intercrop garlic with pomegranate tree to control pomegranate wilt.[Methods] Root exudates of garlic is cultivated in 1/5 concentration of MS solution and dis... [Objectives] This paper aims to explore the possibility to intercrop garlic with pomegranate tree to control pomegranate wilt.[Methods] Root exudates of garlic is cultivated in 1/5 concentration of MS solution and distilled water is examined in lab to test their effect to growth of mycelia of pomegranate wilt pathogen(Ceratocystis fimbriata)and multiplication of Bacillus subtilis.[Results] The result shows that garlic root exudates whatever cultivated in MS solution or distilled water could not inhibit or promote mycelia growth of C.fimbriata.However,garlic root exudates cultivated in both methods effectively promote multiplication of B.subtilis.[Conclusions] It is suggested that intercropping garlic with pomegranate tree by combining application B.subtilis could be a promising way to prevent pomegranate wilt spread in practice. 展开更多
关键词 GARLIC Pomegranate wilt Ceratocystis fimbriata Bacillus subtilis Root exudates
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Analysis of the major components of root exudates released from several economic forest tree using GC-MS 被引量:2
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作者 孙浩元 王玉柱 杨丽 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第2期127-129,共3页
In 2000 and 2001, 1-year-old seedlings of 7 economic tree species including chestnut, apricot, persimmon, peach, walnut, pear and apple were cultured in garden pots that had a diameter of 40 cm and were filled with cl... In 2000 and 2001, 1-year-old seedlings of 7 economic tree species including chestnut, apricot, persimmon, peach, walnut, pear and apple were cultured in garden pots that had a diameter of 40 cm and were filled with clean sand. The major components of exudates released from their roots were isolated and analysed by GC-MS. Totally 200 kinds of organic chemicals were isolated, of which 3 kinds i.e. naphthalene, dimethylbenzene and dibutyl phthalate were principally controlled pollutants according to 'Blacklist of Principal Environment Pollutants in China' and the standard of U.S. Environmental Protection Agency (EPA). The research result provided theoretical evidence for selecting low-pollution economic forest crops in the water source protection area in Miyun Reservoir. 展开更多
关键词 Economic forest tree Root exudates COMPONENTS
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The Effects of Climate,Soil and Cultivar on the Content of Surface Trichome Exudates from Fresh Flue-cured Leaves
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作者 朱显灵 潘文杰 +2 位作者 李章海 徐增汉 陈懿 《Agricultural Science & Technology》 CAS 2014年第11期1838-1843,共6页
[Objective] The aim was to study the effect of climate and soil on the content of surface trichome exudates from fresh flue-cured leaves. [Method] The experiment was conducted in 2009 in Longgang, Weining and Tianzhu ... [Objective] The aim was to study the effect of climate and soil on the content of surface trichome exudates from fresh flue-cured leaves. [Method] The experiment was conducted in 2009 in Longgang, Weining and Tianzhu of Guizhou Province with flue-cured tobacco variety Yun 85. Mature tobacco leaves were taken from lower, middle and upper plant positions respectively and major cuticular com-ponents of the leaves were extracted with methylene chloride and their chemical compositions were analyzed with GC-MS. [Result] The result showed that there was large difference among trichome exudates of leaves grown under different climatic conditions. The leaf trichome exudates from Tianzhu were quite higher than those from Weining and Longgang, and trichome exudates difference between Tianzhu and Longgang was significant. Soil conditions had considerable effect on the content of tobacco leaf surface trichome exudates, leaf from Longgang soil had highest con-tent, fol owed by Tianzhu soil leaf, Weining soil leaf had lowest content. Under vari-ous climatic conditions, the contents of leaf trichome exudates of same soil were in-consistent, indicating the presence of certain climate and soil factor interaction; The contents of leaf trichome exudates from four cultivars in Longgang showed large difference, Nanjiang 3 was the lowest, fol owed by K326, Guiyan 201 was high, and Yunyan85 the highest. The content of leaf trichome exudates of Yunyan85 was more than two times of that of Nanjiang 3. [Conclusion] The Effect of climate factor on the content of leaf trichome exudates was greater than that of cultivar, which was then larger than soil condition. 展开更多
关键词 Flue-cured Tobacco Climate Soil Cultivar Trichome exudates Effect
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Root Exudates, Rhizosphere Zn Fractions, and Zn Accumulation of Ryegrass at Different Soil Zn Levels 被引量:23
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作者 XU Wei-Hong LIU Huai +1 位作者 MA Qi-Fu XIONG Zhi-Ting 《Pedosphere》 SCIE CAS CSCD 2007年第3期389-396,共8页
A glasshouse experiment was conducted using a root-bag technique to study the root exudates, rhizosphere Zn fractions, and Zn concentrations and accumulations of two ryegrass cultivars (Lolium perenne L. cvs. Airs an... A glasshouse experiment was conducted using a root-bag technique to study the root exudates, rhizosphere Zn fractions, and Zn concentrations and accumulations of two ryegrass cultivars (Lolium perenne L. cvs. Airs and Tede) at different soil Zn levels (0, 2, 4, 8, and 16 mmol kg^-1 soil). Results indicated that plant growth of the two cultivars was not advérsely affected at soil Zn level ≤ 8 mmol kg^-1. Plants accumulated more Zn as soil Zn levels increased, and Zn concentrations of shoots were about 540 μg g^-1 in Aris and 583.9 μg g^-1 in Tede in response to 16 mmol Zn kg^-1 soil. Zn ratios of shoots to roots across the soil Zn levels were higher in Tede than in Airs, corresponding with higher rhizosphere available Zn fractions (exchangeable, bound to manganese oxides, and bound to organic matter) in Airs than in Tede. Low-molecular-weight (LMW) organic acids (oxalic, tartaric, malic, and succinic acids) and amino acids (proline, threonine, glutamic acid, and aspartic acid, etc.) were detected in root exudates, and the concentrations of LMW organic acids and amino acids increased with addition of 4 mmol Zn kg^-1 soil compared with zero Zn addition. Higher rhizosphere concentrations of oxalic acid, glutamic acid, alanine, phenylalanine, leucine, and proline in Tede than in Airs likely resulted in increased Zn uptake from the soil by Tede than by Airs. The results suggested that genotypic differences in Zn accumulations were mainly because of different root exudates and rhizosphere Zn fractions. 展开更多
关键词 plant Zn accumulation rhizosphere Zn fractions root exudates RYEGRASS soil Zn level
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Effects of maize root exudates and organic acids on the desorption of phenanthrene from soils 被引量:14
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作者 ZHU Yanhong, ZHANG Shuzhen, HUANG Honglin, WEN Bei State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第7期920-926,共7页
The effects of maize root exudates and low-molecular-weight-organic anions (LMWOAs) on the desorption of phenanthrene from eight artificially contaminated soils were evaluated. A significant negative correlation was... The effects of maize root exudates and low-molecular-weight-organic anions (LMWOAs) on the desorption of phenanthrene from eight artificially contaminated soils were evaluated. A significant negative correlation was observed between the amounts of phenanthrene desorbed and the soil organic carbon (SOC) contents (P 〈 0.01), and the influences of soil pH and clay content on phenanthrene desorption were insignificant (P 〉 0.1). Neither maize root exudates nor oxalate and citrate anions influenced desorption of phenanthrene with the addition of NaN3. A faster phenanthrene desorption occurred without the addition of NaN3 in the presence of maize root exudates than oxalate or citrate due to the enhanced degradation by root exudates. Without the addition of NAN3, oxalate or citrate at different concentrations could inhibit phenanthrene desorption to different extents and the inhibiting effect by citrate was more significant than by oxalate. This study leads to the conclusion that maize root exudates can not enhance the desorption under abiotic condition with the addition of NaN3 and can promote the desorption of phenanthrene in soils without the addition of NaN3. 展开更多
关键词 PHENANTHRENE DESORPTION low-molecular-weight-organic anions (LMWOAs) root exudates SOILS
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Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China 被引量:13
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作者 YongQing LUO XueYong ZHAO +2 位作者 Olof ANDRéN YangChun ZHU WenDa HUANG 《Journal of Arid Land》 SCIE CSCD 2014年第4期423-431,共9页
Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not f... Plant root exudates contain various organic and inorganic components that include glucose, citric and oxalic acid. These components affect rhizosphere microbial and microfaunal activities, but the mechanisms are not fully known. Studies concerned from degraded grassland ecosystems with low soil carbon(C) contents are rare, in spite of the global distribution of grasslands in need of restoration. All these have a high potential for carbon sequestration, with a reduced carbon content due to overutilization. An exudate component that rapidly decomposes will increase soil respiration and CO2 emission, while a component that reduces decomposition of native soil carbon can reduce CO2 emission and actually help sequestering carbon in soil. Therefore, to investigate root exudate effects on rhizosphere activity, citric acid, glucose and oxalic acid(0.6 g C/kg dry soil) were added to soils from three biotopes(grassland, fixed dune and mobile dune) located in Naiman, Horqin Sandy Land, Inner Mongolia, China) and subjected to a 24-day incubation experiment together with a control. The soils were also analyzed for general soil properties. The results show that total respiration without exudate addition was highest in grassland soil, intermediate in fixed dune and lowest in mobile dune soil. However, the proportion of native soil carbon mineralized was highest in mobile dune soil, reflecting the low C/N ratio found there. The exudate effects on CO2-C emissions and other variables differed somewhat between biotopes, but total respiration(including that from the added substrates) was significantly increased in all combinations compared with the control, except for oxalic acid addition to mobile dune soil, which reduced CO2-C emissions from native soil carbon. A small but statistically significant increase in pH by the exudate additions in grassland and fixed dune soil was observed, but there was a major decrease from acid additions to mobile dune soil. In contrast, electrical conductivity decreased in grassland and fixed dune soil and increased in mobile dune. Thus, discrete components of root exudates affected soil environmental conditions differently, and responses to root exudates in soils with low carbon contents can differ from those in normal soils. The results indicate a potential for, e.g., acid root exudates to decrease decomposition rate of soil organic matter in low carbon soils, which is of interest for both soil restoration and carbon sequestration. 展开更多
关键词 artificial root exudates carbon mineralization pH variation deteriorated grassland ecosystem Inner Mongolia
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The Extraction,Isolation and Identification of Exudates from the Roots of Flaveria bidentis 被引量:6
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作者 YANG Xing ZHANG Li-hui +4 位作者 SHI Cui-ping SHANG Yan ZHANG Jin-lin HAN Jian-min DONG Jin-gao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期105-114,共10页
Large amounts ofFlaveria bidentis's root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-~) can have a certain inhibiti... Large amounts ofFlaveria bidentis's root culturing solution were obtained by using DFT (deep flow technique) equipment and these solution which was vacuum concentrated (10, 20 mg mL-~) can have a certain inhibition on Triticum aestivum, Cucumis sativus, Raphanus sativus, Amaranthus retroflexus, Setaria viridis, Chenopodium album, Echinochloa crusgalli and Chloris virgata. This outcome suggested some active compounds in the root exudates ofFIaveria bidentis can inhibit the germination, seedling elongation and root length. The dichloromethane extract of root exudates was identificated by GC-MS, and 29 kinds of compounds, including esters, hydrocarbons, ketones, thiazole, amines, etc. were obtained and the phthalate n-octyl ester, phthalate 2-ethylhexyl ester were proved to be allelochemicals. The culturing solution of root exudates was separated through the resin column and silica gel column and a component inhibiting seedling height, root length and fresh weight of wheat was got. There were 6 kinds of organic compounds in this component including dioctyl phthalate, 1,2-phthalate, mono(2-ethylhexyl) ester by GC-MS. 展开更多
关键词 EXTRACTION ISOLATION IDENTIFICATION exudateS Flaveria bidentis
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Overexpression of a Foreign Bt Gene in Cotton Affects the Low-Molecular-Weight Components in Root Exudates 被引量:6
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作者 YAN Wei-Dong SHI Wei-Ming LI Bao-Hai ZHANG Min 《Pedosphere》 SCIE CAS CSCD 2007年第3期324-330,共7页
Most research in the past using genetically modified crops (GM crops) has focused on the ecological safety of foreign gene (i.e., the gene flow), gene products (for example, Bt (Bacillus thuringiensis) protein), and t... Most research in the past using genetically modified crops (GM crops) has focused on the ecological safety of foreign gene (i.e., the gene flow), gene products (for example, Bt (Bacillus thuringiensis) protein), and the safety of transgenic food for humans. In this study, changes in both the species and amounts of low-molecular-weight components in cotton (Gossypium hirsutum L.) root exudates after foreign Bt gene overexpression were investigated under different nutritional conditions. Transgenic cotton containing Bt (Bt-cotton), supplemented with all the mineral nutrients, secreted more organic acids than the wild-type cotton (WT). When nitrogen was removed from the full-nutrient solution, the amount of organic acids secretion of Bt-cotton was lesser than that of WT. The roots of the transgenic cotton secreted lesser amounts of amino acids and soluble sugars than the WT roots in the full-nutrient solution. Deficiencies of P and K caused a large increase in the total amino acid and soluble sugar secretions of both Bt-cotton and WT, with larger increases observed in Bt-cotton. Because transferring the foreign Bt gene into cotton can result in alterations in the components of the root exudates, with the effect varying depending on the nutritional status, the cultivation of genetically modified crops, such as Bt-cotton, in soil environments should be more carefully assessed, and the possible effects as a result of the alterations in the root exudate components should be considered. 展开更多
关键词 gene overexpression low-molecular-weight components nutritional status root exudates transgenic cotton
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Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography: I. Development and Assessment of Chromatographic Conditions *1 被引量:4
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作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1998年第2期97-104,共8页
Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile ph... Methods for determining nine low molecular weight organic acids in root exudates were developed by using reversed phase high performance liquid chromatography with UV (ultraviolet) detection at 214 nm. The mobile phase was 18 mmol L -1 kH 2PO 4 adjusted to pH 2.25 with phosphoric acid and the flow rate was 0.3 mL min -1 . The analytical column was a reversed phase silica based C 18 column (Shim pack CLC ODS). The root exudates were collected through submerging the whole root system into aerated deionized water for 2 hours. The filtered exudate solutions were concentrated to dryness by rotary evaporation at 40 °C, dissolved in 10 mL mobile phase. The chromatographic conditions of organic acid determination were analyzed. The results showed that there was a high selectivity and sensitivity in the organic acid determination by reversed phase high performance liquid chromatography. Coefficients of variation for organic acid determination were lower than 10% except lactic acid. The recoveries were consistently between 80.1% to 108.3%. Detection limits were approximately 0.05 to 4.5 mg L -1 for organic acids except succinic acid with the detection limit of 7.0 mg L -1 . Phosphorus deficiency may contribute to the release of organic acids in soybean root exudates especially malic, lactic and citric acids. 展开更多
关键词 high performance liquid chromatography organic acids root exudates SOYBEAN
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Accelerated degradation of a variety of aromatic compounds by Spirodela polyrrhiza-bacterial associations and contribution of root exudates released from S. polyrrhiza 被引量:3
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作者 Hai Hoang Ning Yu +3 位作者 Tadashi Toyama Daisuke Inoue Kazunari Sei Michihiko Ike 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第4期494-499,共6页
Removal experiments of phenol, aniline, 2,4-dichlorophenol, nonylphenol and bisphenol A (BPA) using Spirodela polyrrhiza- bacterial associations revealed that all compounds but BPA underwent accelerated removal. The... Removal experiments of phenol, aniline, 2,4-dichlorophenol, nonylphenol and bisphenol A (BPA) using Spirodela polyrrhiza- bacterial associations revealed that all compounds but BPA underwent accelerated removal. The mechanisms differed depending on the substrates. It was found that S. polyrrhiza has a great ability to release phenolic compound-rich root exudates, and the exudates seem to stimulate bacterial degradation of a variety of aromatic compounds. 展开更多
关键词 accelerated biodegradation aromatic compounds RHIZOSPHERE root exudates Spirodela polyrrhiza
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Effect of Soil Moisture on Release of Low-Molecular Weight Organic Acids in Root Exudates and the Accu-mulation of Iron in Root Apoplasm of Peanut 被引量:3
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作者 ZHENG YI and ZHANG FUSUO (Department of Plant Nutrition, China Agricultural University, Beijing,100094 China) 《Pedosphere》 SCIE CAS CSCD 2000年第4期333-338,共6页
A three-compartments rhizobox was designed and used to study the low-molecular-weight organic acids in root exudates and the root apoplastic iron of "lime-induced chlorosis" peanut grown on a calcareous soil... A three-compartments rhizobox was designed and used to study the low-molecular-weight organic acids in root exudates and the root apoplastic iron of "lime-induced chlorosis" peanut grown on a calcareous soil in relation to different soil moisture conditions. Results showed that chlorosis of peanuts developed under condition of high soil moisture level (250 g kg-1), while peanuts grew well and chlorosis did not develop when soil moisture was managed to a normal level (150 g kg-1). The malic acid, maleic acid and succinic acid contents of chlorotic peanut increased by 108.723, 0.029 and 22.446 ig cm-2, respectively, compared with healthy peanuts. The content of citric acid and fumaric acid also increased in root exudates of chlorotic peanuts. On Days 28 and 42 of peanut growth, the accumulation of root apoplastic iron in chlorotic peanuts was higher than that of healthy peanuts. From Day 28 to Day 42, the mobilization percentages of chlorotic peanuts and healthy peanuts to root apoplastic iron were almost the same, being 52.4% and 52.8%, respectively, indicating that the chlorosis might be caused by the inactivation of iron within peanut plant grown on a calcareous soil under high soil moisture conditions. 展开更多
关键词 apoplastic iron PEANUT root exudates soil moisture
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Determination of Organic Acids in Root Exudates by High Performance Liquid Chromatography:Ⅱ.Influence of Several Testing Conditions 被引量:2
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作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1999年第1期45-52,共8页
Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed- phase C18 column, using high performance liquid chromatograph... Effects of column temperature and flow rate on separation of organic acids were studied by determining nine low-molecular-weight organic acids on reversed- phase C18 column, using high performance liquid chromatography (HPLC) with a wavelength of UV (ultraviolet) 214 urn and a mobile phase of 18 mmol L-1 KH2PO4 buffer solution (pH 2.1). The thermal stability of organic acids was determined by comparing the recoveries of organic acids in different temperature treatments. The relationships between column temperature, flow rate or solvent pH and retention time were analyzed. At low solvent pH, separation efficiency of organic acids was increased by raising the flow rate of the solvent because of lowering the retention time of organic acids. High column temperature was unfavorable for the separation of organic acids. The separating effect can be enhanced through reducing column temperature in organic acid determination due to increasing retention time. High thermal stability of organic acids with low concentrations was observed at temperature of 40 ℃-45℃. Sensitivity and separation effect of organic acid determination by HPLC were clearly improved by a combination of raising flow rate and lowering column temperature at low solvent pH. 展开更多
关键词 chromatographic conditions high performance liquid chromatography (HPLC) organic acids root exudates
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Differential Responses of Phytophthora sojae to Seed Exudates of Host Soybean and Non-host Maize 被引量:1
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作者 Wen Jing-zhi Zhang Zhuo-qun +6 位作者 Xu Ying Song Guang-mei Chen Yu-fei Gao Xin-ying Zhao Yu-qi Jia Meng-zhen Liang Jia-yu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2019年第3期1-8,共8页
In order to clarify the differential response of Phytophthora sojae to the seed exudates of host soybean and non-host maize and understand the relationship between seed exudates and host selectivity of Phytophthora so... In order to clarify the differential response of Phytophthora sojae to the seed exudates of host soybean and non-host maize and understand the relationship between seed exudates and host selectivity of Phytophthora sojae, non-host maize Suiyu 23 and susceptible host soybean Sloan seed exudates were collected to measure their influence on mycelial growth, formation and germination of oospores, chemotaxis, encystment and germination of zoospores of Phytophthora sojae. The results showed that nonhost maize seed exudates exhibited repellency to zoospores of Phytophthora sojae, it also could significantly inhibited Phytophthora sojae mycelial growth, formation of oospores compared with the control;compared with host soybean, non-host maize seed exudates could significantly inhibited Phytophthora sojae mycelial growth, formation and germination of oospores, germination of cysts, which indicated that the seed exudates was the critical factor to host selectivity of Phytophthora sojae and the maize seed exudates was closely related to its non-host resistance. 展开更多
关键词 PHYTOPHTHORA sojae SEED exudate non-host resistance
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Determination of Organic Acids in Root Exudates byHigh Performance Liquid Chromatography: III. Effectsof Interfering Factors 被引量:1
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作者 SHENJIANBO ZHANGFUSUO 《Pedosphere》 SCIE CAS CSCD 1999年第2期97-104,共8页
A solution culture experiment was conducted to investigate the effects of collection time and interferingions on separation and determination of low-molecular-weight organic acids in root exudates of soybeanusing the ... A solution culture experiment was conducted to investigate the effects of collection time and interferingions on separation and determination of low-molecular-weight organic acids in root exudates of soybeanusing the method for directly collecting root exudates. The suitable collection time of root exudates andthe interfering ions affecting organic acid determination were determined. The method for removing theinterfering ions was established and analyzed. The release amount of root exudates increased with theincrease of collection time from 0 to 120 min but decreased with increasing of collection time from 120 to 240min. The maximum exuding amounts of organic acids were observed in root exudates at the collection time of120 min. There was a significant difference of organic acid components between the treatments of collectiontime of 120 min and 240 min. Citric acid was found only in the treatment of 120 min collection time. NO3-was the main interfering ion in organic acid determination and had the same retention time as oxalic acid.Anion exchangs resin (SAX) properly treated by HPLC (high performance liquid chromatography) solventcould remove NO3- anion in sample solution of root exudates, thus enhancing the recoveries of organic acidsin root exudates. There was no significant effect of the chemicals added into sample solution such as H3PO4,SAX and KNO3 on the retention time of organic acids. 展开更多
关键词 collection time interfering factor low-molecular-weight organic acid root exudates
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Studies on the Allelopathic Potential of Corn (Zea mays L.) Aqueous Extracts and Root Exudates 被引量:2
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作者 Zakiya A. Hassan 《Journal of Agricultural Science and Technology(A)》 2012年第4期432-437,共6页
This investigation was carried out at Faculty of Agriculture and Forestry-University of Duhok/Kurdistan-Iraq. Three experiments were included in this investigation: (1) First experiment was a bioassay related to th... This investigation was carried out at Faculty of Agriculture and Forestry-University of Duhok/Kurdistan-Iraq. Three experiments were included in this investigation: (1) First experiment was a bioassay related to the germination performance, shoot and root development of corn (Zea mays L.) and peanut (Arachishypogaea) at two concentrations of root (3% and 1.5%) and shoot (12% and 6%) aqueous extracts of corn medium; (2) The second experiment dedicated to the intercropping of corn and peanut at four treatments; (3) While the third experiment involved the effect of peanut root exudation on growth of corn. Experiment results revealed that corn shoot and root water extracts highly inhibited seed germination of both corn and peanut, the inhibitory of shoot extract was more than root aqueous extract. While its effect on the seedling growth was vice versa as compared with control treatment, there was an increase in root and shoot length of both corn and peanut when grown in corn aqueous extracts. Intercropping experiment results has stimulated most traits of peanut under studying. Also for corn, there was apparent and significant increase in all characteristics as compared with control. It was further confirmed from the results of peanut root exudates that had all studied characters of corn were stimulated than the control treatment. 展开更多
关键词 Allelopathic potential COM PEANUT aqueous extracts root exudates.
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Exogenous Inoculation of Microorganisms Effect on Root Exudates and Rhizosphere Microorganism of Tobaccos 被引量:2
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作者 Qingqing Guo Jun Yu +4 位作者 Jingguo Sun Changjun Wang Shouwen Chen Chunlei Yang Yong Yang 《Advances in Microbiology》 2021年第9期510-528,共19页
Studying the relationship between rhizosphere microorganisms and root exudates is of great significance for the interaction between rhizosphere microorganisms and plants, and the prevention and control of soil-borne d... Studying the relationship between rhizosphere microorganisms and root exudates is of great significance for the interaction between rhizosphere microorganisms and plants, and the prevention and control of soil-borne diseases. This article analyzed the effects of different microorganisms on tobacco root exudates and rhizosphere microorganisms. It was found that the bacterial wilt pathogen can greatly increase acids and amines, while the probiotic <i>B. amyloliquefaciens</i> ZM9 can eliminate some acids and amines. The results of the study show that the root exudates of pathogenic bacteria may contain a variety of allelochemicals that cause soil-borne diseases. 展开更多
关键词 Root exudates Rhizosphere Microbes GC-MS
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A novel method for detection of hard exudates from fundus images based on SVM and improved FCM
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作者 高玮玮 SHEN Jian-xin +1 位作者 WANG Ming-hong ZUO Jing 《Journal of Chongqing University》 CAS 2018年第3期77-86,共10页
Diabetic retinopathy(DR) is one of the most important causes of visual impairment. Automatic recognition of DR lesions, like hard exudates(EXs), in retinal images can contribute to the diagnosis and screening of the d... Diabetic retinopathy(DR) is one of the most important causes of visual impairment. Automatic recognition of DR lesions, like hard exudates(EXs), in retinal images can contribute to the diagnosis and screening of the disease. To achieve this goal, an automatically detecting approach based on improved FCM(IFCM) as well as support vector machines(SVM) was established and studied. Firstly, color fundus images were segmented by IFCM, and candidate regions of EXs were obtained. Then, the SVM classifier is confirmed with the optimal subset of features and judgments of these candidate regions, as a result hard exudates are detected from fundus images. Our database was composed of 126 images with variable color, brightness, and quality. 70 of them were used to train the SVM and the remaining 56 to assess the performance of the method. Using a lesion based criterion, we achieved a mean sensitivity of 94.65% and a mean positive predictive value of 97.25%. With an image-based criterion, our approach reached a 100% mean sensitivity, 96.43% mean specificity and 98.21% mean accuracy. Furthermore, the average time cost in processing an image is 4.56 s. The results suggest that the proposed method can efficiently detect EXs from color fundus images and it could be a diagnostic aid for ophthalmologists in the screening for DR. 展开更多
关键词 diabetic retinopathy improved FCM support vector machines hard exudates fundus images
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Effects of Grafting on Root Exudates of Cucumber and Rhizosphere Environment under Copper Stress
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作者 Hua LI Hongjun HE +2 位作者 Tengfei LI Xin LI Zikun ZHANG 《Agricultural Science & Technology》 CAS 2013年第11期1594-1598,共5页
[Objective] This study to aimed to investigate the effects of Cu stress on root exudates and microbial activities in rhizosphere of grafted and ungrafted cucum-ber seedlings, and therefore to elucidate the microbial m... [Objective] This study to aimed to investigate the effects of Cu stress on root exudates and microbial activities in rhizosphere of grafted and ungrafted cucum-ber seedlings, and therefore to elucidate the microbial mechanism of grafting for in-creasing cucumber plants tolerance to Cu stress [Method] Four treatments: (1) un-grafted seedlings + test soil (U0); (2) ungrafted seedlings + test soil + CuSO4·5H2O (U1); (3) grafted seedlings + test soil (G0); (4) grafted seedlings + test soil + Cu-SO4·5H2O (G1) were set in the pot culture experiment. The contents of free amino acids, organic acids, phenolic acid and sugars, microbial population and enzyme ac-tivity in the four treatment were measured, respectively. [Result] The secretion of amino acids and organic acids were increased under Cu stress. The amino acids secretions of grafted seedlings roots were obviously higher than ungrafted seedlings except for Phe and Val. At the same time, the secretion of oxalic acid, malic acid, acetic acid, citric acid, cinnamic acid, ρ-hydroxybenzoic acid and benzoic acid of grafted seedlings were significantly higher than ungrafted seedlings as wel . There-fore, more Cu2+ were restricted in soil by chelating, complexing and precipitation with root exudates, and its toxicity was decreased. The soil microbial biomass C and N in grafted cucumber rhizosphere were significantly higher than those in ungrafted cu-cumber rhizosphere, whereas basal respiration and metabolic quotient were signifi-cantly lower. Under Cu stress, the numbers of actinomyces and nitrogen fixing bac-teria decreased and the number of fungi increased significantly, whereas there was no significant difference in amounts of bacteria. The numbers of bacteria, actino-myces, and nitrogen fixing bacteria in grafted cucumber rhizosphere were significant-ly higher than those in ungrafted cucumber rhizosphere, but the number of fungi was opposite. The activities of soil urease, phosphatase, sucrase and catalase in grafted cucumber rhizosphere were significantly higher than those in ungrafted cu-cumber rhizosphere. [Conclusion] These indicated that the soil microbial environment and soil enzymes activities were improved by grafting under Cu stress, and as a re-sult, the adaptability of cucumber to Cu stress was improved. 展开更多
关键词 GRAFTING Cu stress Root exudates Soil microorganisms Soil enzymes
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