CELLULAR SUBSTANCE EXUDATION AND SEED VIGOUR

In this paper, seeds of pinus koraiensis which has a characteristic of deep dormancy were selected as an experiment material, and the relation of cellular substance exudation to seed vigour is discussed based on the dormant state, the different measuring parts and the imbibed state of seeds before testing, as well as on the respiration of embryo and endosperm. The major measured results arc as follows: (1) After soaking for 24h, the dry embryo conductivity of sccdlot L is greater that than of sccdlot H: (2) The substance exudation of dry embryo of sccdlot H is less than that of sccdlot L; (3) After seeds imbibed, the substance exudation of dormant embryo of sccdlot H is more than that of sccdlot L; (4) After germination hastening treatment, the substance exudation of H embryos is greater than that of L embryos; (5) After artificially accelerated ageing treatment, the embryo conductivity of imbibed seeds has a positive correlation with seed vigour.

Effects of Chemical Composition and Microstructure on Exudation of Fused Cast AZS Refractory Materials

The fused cast alumina-zirconia-silica(AZS)refractory is an indispensable material of the glass melting furnace,because of its outstanding corrosion resistance and low pollution to glass production.The exudation is one important index to evaluate the performance of fused cast AZS refractory products.In order to study the effects of chemical composition and microstructure on the exudation of fused cast AZS refractory materials,three types of fused-cast AZS refractory bricks(AZS33#,AZS36#and AZS41#)were selected from several companies as the research object,and their composition,bulk density,apparent porosity,the value of exudation,static corrosion rate and microstructure were discussed.The results show that the chemical composition,especially the content of SiO2 and Na2O,and the distribution of zirconia would greatly affect the content and viscosity of glass phase,thus affecting the glass exudation.This work will provide technical reference for the development of low exudation AZS refractories.

Nursing Study on Reducing the Incidence of Bleeding and Exudation after PICC Catheterization by Blunt Separation Combined with Early Sheath Removal

Objective:To compare the effects of blunt separation combined with early sheath removal and conventional catheterization on the incidence of bleeding,exudation and subcutaneous congestion after peripherally inserted central catheter(PICC).Methods:250 patients with PICC catheterization in our hospital were selected,including 125 in the control group and 125 in the observation group.The conventional catheterization method was used in the control group:The sheath was removed by scalpel skin expansion and complete tube delivery in place.The observation group used blunt separation combined with early sheath removal.The success rate of one-time sheath delivery,immediate bleeding,24-hour bleeding and exudation were compared.Results:The success rate of sheath delivery in the observation group was 100%;The amount of immediate blood loss and blood loss 24h after catheterization in observation group was obviously lower than that in the control group,with statistical significance(P<0.05).There were 6 cases of exudation in the control group and no exudation in the observation group.There was significant difference in the incidence between the two groups(P<0.05);There were 10 cases of subcutaneous congestion in the control group and 2 cases of subcutaneous congestion in the observation group.There was significant difference in the incidence between the two groups(P<0.05);Conclusion:Blunt separation combined with early sheath removal can reduce the occurrence of local blood and fluid leakage after PICC catheterization.

Zinc chemical forms and organic acid exudation in non-heading Chinese cabbages under zinc stress

As an essential element, zinc also is a heavy metal. Non-heading Chinese cabbage showed obvious tolerance to Zn stress in former research. To further understand the mechanisms involved in Zn adaptability and detoxification, two genotypes Suzhouqing and Aijiaohuang were selected to investigate the chemical forms of Zn and root exudation. Zinc stress obvious strained the plant growth, and Aijiaohuang was more injured than Suhouqing under Zn stress. Under normal Zn levels, the chemical forms of Zn were diverse in three organs between genotypes. Results showed extractions of 2% HAc, 80% ethanol and 1 M NaCl were separately dominant in roots, petioles and leaves. However, under Zn stress (13 mg·L–1 and 52 mg·L–1) most of the Zn was extracted by 1M NaCl, and the subdominant amount of Zn was extracted by 80% ethanol. In the control only four types of organic acid could be detected. While under Zn stress, oxalic acid, tartaric acid, malic acid, lactic acid, acetic acid, citric acid and amber acid were all detected, so it could be speculated Zn detoxification with organic ligands or integrated with pectates and proteins in cells might be responsible for the adaptation of Zn stress in Chinese cabbage.

Effect of Zn deficiency and excessive bicarbonate on the allocation and exudation of organic acids in two Moraceae plants

The effect of zinc(Zn) deficiency and excessive bicarbonate on the allocation and exudation of organic acids in plant organs(root, stem, and leaf) and root exudates of two Moraceae plants(Broussonetia papyrifera and Morus alba) were investigated. Two Moraceae plants were hydroponically grown and cultured in nutrient solution in four different treatments with 0.02 mM Zn or no Zn,combined with no or 10 mM bicarbonate. The variations of organic acids in different plant organs were similar to those of root exudates in the four treatments except B. papyrifera, which was in a treatment that was a combination of 0.02 mM Zn and no bicarbonate. The response characteristics in the production, translocation, and allocation of organic acids in the plant organs and root exudates varied with species and treatments. Organic acids in plant organs and root exudates increased under Zn-deficient conditions,excessive bicarbonate, or both. An increase of organic acids in the leaves resulted in an increase of root-exuded organic acids. B. papyrifera translocated more oxalate and citrate from the roots to the rhizosphere than M. alba under the dual influence of 10 mM bicarbonate and Zn deficiency. Organic acids of leaves may be derived from dark respiration and photorespiration. By comparison, organic acids in stems, roots, and root exudates may be derived from dark respiration and organic acid translocation from the leaves. These results provide evidence for the selective adaptation of plants to environments with low Zn levels or high bicarbonate levels such as a karst ecosystem.

Evolution of Diabetic Maculopathy from Marked Exudation to Subretinal Fibrosis: Clinical and Spectral Domain Optical Coherence Tomography Features

Diabetic maculopathy with marked exudation may lead to subretinal fibrosis. Two patients observed over multiple years evolved from macular exudation into subretinal fibrosis with severe visual loss. Spectral domain optical coherence tomography and color photographs document the clinical changes.

Root Cluster Formation and Citrate Exudation of White Lupin （Lupinus albus L.） as Related to Phosphorus Availability

Abstract: A split-root system was used to investigate whether the external or internal P concentration controls root cluster formation and citrate exudation in white lupin (Lupinus albus L.) grown under controlled conditions. In spite of low P concentrations in the shoots and roots of the -P plant, its dry weight was not reduced compared with the +P plant. Supplying external P (0.25 mmol/L) to one root half resulted in an increase in P concentration not only in the shoot, but also in the P-deprived root half, indicating P cycling within the plants. Omitting P from both split-root pots stimulated root cluster formation in both root halves, whereas P supply to one root half stimulated root cluster formation at the beginning of the treatment. Neither P supply to just one root half continuously nor resupply of P to one root half after 19 d of P starvation inhibited root cluster formation on the P-deprived side, although the concentration of P in this root half and shoot increased markedly. The results indicate that root cluster formation in L. albus is controlled by both shoot and root P concentrations. The rates of citrate exudation by both root halves with P deficiency were higher than those of the one root half supplied with P only. In the treatment with one root half supplied with P, the rates of citrate exudation by either the P-supplied or -deprived root halves were almost the same, regardless of P concentration in the roots. The results suggest that internal P concentration controls root cluster formation and citrate exudation in white lupin, but these processes may be regulated by different mechanisms.

Efficacy of lidocaine wet compress combined with red-light irradiation for chronic wounds

BACKGROUND Chronic wounds that fail to progress through normal phases of healing present a significant healthcare burden owing to prolonged treatment and associated costs.Traditional wound care typically involves regular dressing changes,which can be painful.Recent approaches have explored the use of lidocaine to manage pain and red-light irradiation(RLI),known for its anti-inflammatory and cell proliferation effects,to potentially enhance wound healing.AIM To investigate the therapeutic efficacy of lidocaine wet compression(LWC)combined with RLI for chronic wounds.METHODS We enrolled 150 patients with chronic wounds from the Wound and Ostomy Outpatient Clinic of the Second Hospital of Anhui Medical University from April to September 2022.The wounds were treated with dressing changes.The patients were randomly assigned to the control and experimental groups using a random number table and given the same first dressing change(2%LWC for 5 min and routine dressing change).From the second dressing change,in addition to 2%LWC for 5 min and routine dressing change,the experimental group received RLI,whereas the control group continued to receive the same LWC and dressing change.The first and second dressing changes were performed on days 1 and 2,respectively.The third dressing change was performed 3 d after the second change.The frequency of subsequent dressing changes was determined based on wound exudation and pain.Pain during the first three dressing changes was evaluated in both groups.The average number of dressing changes within 28 d and the degree of wound healing on day 28 were also recorded.RESULTS During the initial dressing change,no noticeable differences were observed in the pain levels experienced by the two groups,indicating similar pain tolerance.However,during the second and third dressing changes,the experimental group reported significantly less pain than the control group.Furthermore,over 28 d,the experimental group required fewer dressing changes than the control group.CONCLUSION Notably,the effectiveness of wound healing on the 28th day was significantly higher in the experimental group than that of in the control group.The combination of LWC and RLI was effective in reducing early-stage pain,promoting wound healing,decreasing the frequency of dressing changes,and enhancing patients’overall quality of life with chronic wounds.

De novel heterozygous copy number deletion on 7q31.31-7q31.32 involving TSPAN12 gene with familial exudative vitreoretinopathy in a Chinese family

AIM:To investigate the genetic and clinical characteristics of patients with a large heterozygous copy number deletion on 7q31.31-7q31.32.METHODS:A family with familial exudative vitreoretinopathy(FEVR)phenotype was included in the study.Whole-exome sequencing(WES)was initially used to locate copy number variations(CNVs)on 7q31.31-31.32,but failed to detect the precise breakpoint.The long-read sequencing,Oxford Nanopore sequencing Technology(ONT)was used to get the accurate breakpoint which is verified by quantitative real-time polymerase chain reaction(QPCR)and Sanger Sequencing.RESULTS:The proband,along with her father and younger brother,were found to have a heterozygous 4.5 Mb CNV deletion located on 7q31.31-31.32,which included the FEVRrelated gene TSPAN12.The specific deletion was confirmed as del(7)(q31.31q31.32)chr7:g.119451239_123956818del.The proband exhibited a phase 2A FEVR phenotype,characterized by a falciform retinal fold,macular dragging,and peripheral neovascularization with leaking of fluorescence.These symptoms led to a significant decrease in visual acuity in both eyes.On the other hand,the affected father and younger brother showed a milder phenotype.CONCLUSION:The heterozygous CNV deletion located on 7q31.31-7q31.32 is associated with the FEVR phenotype.The use of long-read sequencing techniques is essential for accurate molecular diagnosis of genetic disorders.

IM-EDRD from Retinal Fundus Images Using Multi-Level Classification Techniques

In recent years,there has been a significant increase in the number of people suffering from eye illnesses,which should be treated as soon as possible in order to avoid blindness.Retinal Fundus images are employed for this purpose,as well as for analysing eye abnormalities and diagnosing eye illnesses.Exudates can be recognised as bright lesions in fundus pictures,which can be thefirst indicator of diabetic retinopathy.With that in mind,the purpose of this work is to create an Integrated Model for Exudate and Diabetic Retinopathy Diagnosis(IM-EDRD)with multi-level classifications.The model uses Support Vector Machine(SVM)-based classification to separate normal and abnormal fundus images at thefirst level.The input pictures for SVM are pre-processed with Green Channel Extraction and the retrieved features are based on Gray Level Co-occurrence Matrix(GLCM).Furthermore,the presence of Exudate and Diabetic Retinopathy(DR)in fundus images is detected using the Adaptive Neuro Fuzzy Inference System(ANFIS)classifier at the second level of classification.Exudate detection,blood vessel extraction,and Optic Disc(OD)detection are all processed to achieve suitable results.Furthermore,the second level processing comprises Morphological Component Analysis(MCA)based image enhancement and object segmentation processes,as well as feature extraction for training the ANFIS classifier,to reliably diagnose DR.Furthermore,thefindings reveal that the proposed model surpasses existing models in terms of accuracy,time efficiency,and precision rate with the lowest possible error rate.

A Novel Soft Clustering Method for Detection of Exudates

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.

蟛蜞菊根分泌物的异种克生作用及初步分离

蟛蜞菊根分泌物的异种克生作用及初步分离曾任森，林象联，谭惠芬，曾强（华南农业大学农业生态室，广州５１０６４２）（南开大学元素有机化学研究所，天津３０００７）ＡｌｌｅｌｏｐａｔｈｉｃＥｆｆｅｃｔｓａｎｄＰｒｅｌｉｍｉｎａｒｙＩｓｏｌａｔｉｏｎｏｆＲｏｏ...

The rhizosphere microbial complex in plant health:A review of interaction dynamics

Climate change,urbanization,and population increase limit food availability.To sustain human existence,there is the need to increase food and agricultural production to mitigate the impact of these factors.Scientists have been working for years on ways to increase food production.From plant breeding techniques to soil science,scientists have made tremendous progress.The rhizobiome has been proven to be important to crop production,and the impact of the rhizobiome on plant health cannot be overemphasized.Being rich in diverse complex microbial interactions,the rhizosphere has become a major force in recent plant growth promotion studies.The upsurge in next-generation sequencing applications with the various“omics”technologies is helping to unearth information relating to rhizosphere impact on plant growth.Explaining the complex interactions between and across microbial species present in the rhizosphere is important to further enhance our understanding of their mechanistic and mutualistic functions.Knowledge from this can be used in rhizosphere biome engineering for improved plant growth and yield in the face of the various biotic and abiotic challenges.

Application of ferrous sulfate alleviates negative impact of cadmium in rice(Oryza sativa L.)

Soil contamination with toxic heavy metals[such as cadmium(Cd)]is becoming a serious global problem due to rapid development of social economy.Iron(Fe),being an important element,has been found effective in enhancing plant tolerance against biotic and abiotic stresses.The present study investigated the extent to which different levels of Ferrous sulphate(FeSO_(4))modulated the Cd tolerance of rice(Oryza sativa L.),when maintained in artificially Cd spiked regimes.A pot experiment was conducted under controlled conditions for 146 days,by using natural soil,mixed with different levels of CdCl_(2)[0(no Cd),0.5 and 1 mg/kg]together with the exogenous application of FeSO_(4) at[0(no Fe),1.5 and 3 mg/kg]levels to monitor different growth,gaseous exchange characteristics,oxidative stress,antioxidative responses,minerals accumulation,organic acid exudation patterns of O.sativa.Our results depicted that addition of Cd to the soil significantly(P<0.05)decreased plant growth and biomass,gaseous exchange parameters,mineral uptake by the plants,sugars(soluble,reducing,and non-reducing sugar)and altered the ultrastructure of chloroplasts,plastoglobuli,mitochondria,and many other cellular organelles in Cd-stressed O.sativa compared to those plants which were grown without the addition of Cd in the soil.However,Cd toxicity boosted the production of reactive oxygen species(ROS)by increasing the contents of malondialdehyde(MDA),which is the indication of oxidative stress in O.sativa and was also manifested by hydrogen peroxide(H_(2)O_(2))contents and electrolyte leakage to the membrane bounded organelles.Although,activities of various antioxidative enzymes like superoxidase dismutase(SOD),peroxidase(POD),catalase(CAT)and ascorbate peroxidase(APX)and non-enzymatic antioxidants like phenolics,flavonoid,ascorbic acid,anthocyanin and proline contents increased up to a Cd level of 0.5 mg/kg in the soil but were significantly diminished at the highest Cd level of 1 mg/kg in the soil compared to those plants which were grown without the addition of Cd in the soil.The negative impacts of Cd injury were reduced by the application of FeSO_(4) which increased plant growth and biomass,improved photosynthetic apparatus,antioxidant enzymes,minerals uptake together with diminished exudation of organic acids as well as oxidative stress indicators in roots and shoots of O.sativa by decreasing Cd retention in different plant parts.These results shed light on the effectiveness of FeSO_(4) in improving the growth and upregulation of antioxidant enzyme activities of O.sativa in response to Cd stress.However,further studies at field levels are required to explore the mechanisms of FeSO_(4)-mediated reduction of the toxicity of not only Cd,but possibly also other heavy metals in plants.

Effects of maize root exudates and organic acids on the desorption of phenanthrene from soils

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.

Artificial root exudates and soil organic carbon mineralization in a degraded sandy grassland in northern China

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.

Influence of Indian mustard (Brassica juncea) on rhizosphere soil solution chemistry in long-term contaminated soils:A rhizobox study

This study investigated the influence of Indian mustard （Brassicajuncea） root exudation on soil solution properties （pH, dissolved organic carbon （DOC）, metal solubility） in the rhizosphere using a rhizobox. Measurement was conducted following the cultivation of Indian mustard in the rhizobox filled four different types of heavy metal contaminated soils （two alkaline soils and two acidic soils）. The growth of Indian mustard resulted in a significant increase （by 0.6 pH units） in rhizosphere soil solution pH of acidic soils and only a slight increase （〈 0.1 pH units） in alkaline soils. Furthermore, the DOC concentration increased by 17-156 mg/L in the rhizosphere regardless of soil type and the extent of contamination, demonstrating the exudation of DOC from root. Ion chromatographic determination showed a marked increase in the total dissolved organic acids （OAs） in rhizosphere. While root exudates were observed in all soils, the amount of DOC and OAs in soil solution varied considerably amongst different soils, resulting in significant changes to soil solution metals in the rhizosphere. For example, the soil solution Cd, Cu, Pb, and Zn concentrations increased in the rhizosphere of alkaline soils compared to bulk soil following plant cultivation. In contrast, the soluble concentrations of Cd, Pb, and Zn in acidic soils decreased in rhizosphere soil when compared to bulk soils. Besides the influence of pH and DOC on metal solubility, the increase of heavy metal concentration having high stability constant such as Cu and Pb resulted in a release of Cd and Zn from solid phase to liquid phase.

Soluble protein and acid phosphatase exuded by ectomycorrhizal fungi and seedlings in response to excessive Cu and Cd

Fungi and their symbionts can alleviate heavy metal stress by exuding soluble proteins and enzymes. This study examined the role of soluble protein and acid phosphatase （APase） exuded by Xerocomus chrysenteron, an ectomycorrhizal fungus, and the seedlings of its symbiont, Chinese pine （Pinus tabulaeformis）, under conditions of excessive Cu and Cd. The growth type showed that this poorly studied ectomycorrhizal fungus was capable of tolerating high concentrations of Cu, and may be useful in phytoremediation. X. chrysenteron grew well at 80 mg/L Cu, and the EC50 for Cd was 17.82 mg/L. X. chrysenteron also showed enhanced exudation of soluble protein in both isolated and inoculated cultivations under the influence of Cu and Cd. Soluble protein exudation, however, differed under Cu and Cd stress in isolates. In mediums containing Cu, soluble protein exudation increased with concentration, but in mediums containing Cd the content of soluble protein increased to a comparable level at all concentrations. This study demonstrated that soluble protein was related to heavy metal tolerance, although the different ions played different roles. While APase activity in exudates of fungi and seedlings decreased under Cu and Cd stress in comparison to the control, the APase activity in seedlings was maintained by inoculation. Thus, X. chrysenteron facilitated the ability of plant to maintain a normal nutrient uptake, and therefore to protect it from heavy metal toxicity.

Microbial activity related to N cycling in the rhizosphere of maize stressed by heavy metals

A greenhouse experiment was carried out to compare differences in potential activities of ammonification, nitrification and denitrification in rhizosphere and bulk soil in a heavy-metal-stressed system. Exchangeable fractions of Cd, Cu and Cr were all higher in the rhizosphere of maize than in bulk soil. Results showed that the mineralization of N in soil was stimulated by low concentration of Cd. Addition of Cd at low levels stimulated the ammonifying and nitrifying activity in soil, while inhibitory influences were shown at high levels. Nitrifying bacteria was proved to be the most sensitive one, whilst the effect on denitrifying bacteria was very limited. Comparing Cd, Cu and Cr(VI) at 20 mg/kg soil, Cd was the most effective inhibitor of ammonification and denitrification, while Cr(VI) had the strongest inhibitory influence on nitrifying activity. Root exudates played important roles on the different exchangeable metal fractions and bacterial activities between rhizosphere and non-rhizosphere. Nitrate was the main form of mineral N in soil, as well as the main form of N absorbed by plants, but the formation and relative absorption of ammonium were promoted in response to high Cd exposure.

The Extraction,Isolation and Identification of Exudates from the Roots of Flaveria bidentis

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.