Effect of Arbuscular Mycorrhiza Fungal Inoculation with Compost on Yield and Phosphorous Uptake of Berseem in Alkaline Calcareous Soil

An experiment was conducted in pots under natural conditions in alkaline calcareous soil to determine berseem (Trifolium alexandrium) yield and P uptake as affected by Arbuscular mycorrhizal fungi (AMF) inoculation with compost prepared from fresh animal dung and rock phosphate. Data indicated that berseem shoot and roots yields increased significantly (P ≤ 0.05) by inoculation of indigenous mycorrhiza (AMF-I) and half dose of compost. Shoot yield increased as 98% and 76% roots yield as 60% and 52% over control and N and K fertilizers. Maximum and significantly (P ≤ 0.05) increased plant N and P uptake by berseem was observed in the treatment inoculated by commercial mycorrhiza (AMF-II) with full dose of compost followed by the inoculation of AMF-II with half dose of compost. Plants uptake of Cu, Mn and Fe was improved significantly (P ≤ 0.05) by the inoculation of AMF-II with half dose of compost, while Zn uptake was increased in the treatment of AMF-II inoculation with full dose of compost. Maximum and significantly (P ≤ 0.05) increased soil spores density of AMF as 27 spores per 20 g soil was noted by inoculation of AMF-I with half dose of compost, while maximum roots infection intensity in berseem was observed by the inoculation of AMF-I with full dose of compost. Results suggest that inoculation of AMF with compost has potential to improve berseem yields and plants nutrients uptake under given soil conditions.

Effect of Arbuscular Mycorrhiza Fungal Inoculation with Compost on Yield and P Uptake of Wheat in Alkaline Calcareous Soil

An experiment was conducted in pots under natural conditions in alkaline calcareous soil to determine wheat (Triticum aestivum L. c.v. Atta Habib) yield and P uptake as influenced by Arbuscular mycorrhizal fungi (AMF) inoculation with compost prepared from fresh animal dung and rock phosphate. Data indicated that wheat grain, shoot and roots yields increased significantly (P ≤ 0.05) by inoculation of commercial mycorrhiza (AMF-II) and half dose of compost. Grain yield increased by 43% and 37%, shoot by 43% and 39% and roots yield by 51% and 45% over control of N and K fertilizers. Straw yield was maximum as 5075 kg·ha-1 in the treatment of AMF-II inoculation with full dose of compost, which was significantly (P ≤ 0.05) higher as 44% and 40% over control of N and K fertilizers. Maximum and significantly (P ≤ 0.05) higher plant N and P uptake by wheat were observed in the treatment inoculated by indigenous mycorrhiza (AMF-I) with full dose of compost followed by the inoculation of AMF-II with full dose of compost and SSP treatment. Maximum and significantly (P ≤ 0.05) increased soil spores’ density of AMF by 26 spores per 20 g soil with maximum roots infection intensity in wheat were observed by the inoculation of AMF-I with full dose of compost. The AMF-II is slightly better than AMF-I regarding grain, shoot and root yield, whereas AMF-I is better in N, P uptake, soil spore density and their root infection intensity than AMF-II. Alone inoculation and compost application increase the yield and nutrients uptake but the highest improvement was observed with inoculation of AMF with compost. Results suggest that inoculation of AMF with compost has potential to improve wheat yields and plants’ P uptake under given soil conditions.

Seedling Petri-dish inoculation method:A robust,easy-to-use and reliable assay for studying plant-Ralstonia solanacearum interactions

Ralstonia solanacearum causes a lethal bacterial wilt disease in many crops,leading to huge losses in crop production every year.Understanding of plant-R.solanacearum interactions will aid to develop efficient strategies to control the disease.As a soilborne pathogen,R.solanacearum naturally infects plants via roots.A huge limitation in studying plant-R.solanacearum interactions is the large variation of R.solanacearum infection assay due to the variable soil conditions and uneven inoculum exposure.Here,we developed a robust and reliable Petri-dish inoculation method which allows consistent and stable infection in young plant seedlings.This method is easy to use,takes about only 10 days from seed germination to the completion of inoculation assay,and requires less inoculum of bacteria as well as growth chamber space.We proved the efficacy of the seedling Petri-dish inoculation method by analyzing plant defense primed by molecular patterns,resistance of defense-related plant mutants,and virulence of R.solanacearum mutants.Furthermore,we demonstrated that the seedling Petri-dish inoculation method can be applied to other host plants such as tobacco and has great potential for high-throughput screening of resistant plant germplasms to bacterial wilt in the future.

Drought adaptation of Bauhinia faberi var.Microphylla seedlings with dual inoculation of arbuscular mycorrhizal fungi

Bauhinia faberi via.Microphylla(BFM)is an important tree species for vegetation restoration in the dry valley of southwestern China.However,there were few studies on the application of arbuscular mycorrhizal fungi(AMF)in improving the drought adaptation of BFM.In order to investigate the response of BFM to water stress(WS),we tested four inoculation treatments((no AMF,Control),Glomus mosseae(GM),Glomus intraradices(GI),Glomus mosseae+Glomus intraradices(GMI))in pots,experimented under three field water holding capacity(WHC)of 70%,50%and 30%.The changes of seedling survival rate(SR),AMF relative root length colonization rate(Col),growth,photosynthetic parameters,water status and leaf nutrients were examined.The results showed that under 30%WHC drought conditions,SR with dual inoculation of AMF was not higher than with single inoculation of GM,suggesting that increasing the diversity of AMF did not definitely improve plant SR,and that the species of inoculated AMF might have an important impact on SR.The sensitivity of dual inoculated Col to water stress was lower than that of single inoculation,which was more favorable for dual inoculated BFM seedlings adapting to drought environment.The overall drought resistance ability(D)also showed that dual inoculation of AMF improved plant drought adaptation compared with single inoculation,which was related to the higher Col of dual inoculated AMF.This study is of practical importance to promote vegetation restoration in arid areas in a cost-effective and environmentally friendly manner.

Breeding for FHB Resistance via Fusarium Damaged Kernels and Deoxynivalenol Accumulation as Well as Inoculation Methods in Winter Wheat

FHB is one of the most destructive diseases of wheat. Resistance testing depends strongly on inoculation methods, and on measured traits. Therefore a four-year (2009-2012) study was performed using spray inoculation + polyethylene (PE) bag cover, spray inoculation + mist irrigation, and spawn method supported by mist irrigation on 40 genotypes, 20 from Hungary and 20 from IFA Tulln, Austria. Each year four isolates were used in artificial inoculations except the spawn method where stalk debris served the inoculum. Visual Fusarium head blight (FHB) scores, Fusarium damaged kernels (FDK) and deoxynivalenol (DON) contamination were checked. 7680 FHB and FDK, as well as 3840 DON analyses served as the background for the statistical evaluation. The most reliable method used was the spray + polyethylene (PE) bag;the other two were significantly poorer being valid for all traits. The FHB scores were the least reliable, whereas the FDK was much more consequent and the DON gave the best results. The FDK gave much better predictions for DON contamination than FHB. The cultivars responses correlated well at different epidemic severities. The presence of the kernel resistance was confirmed and a new trait as extra kernel susceptibility was described. Presence of DON resistance was confirmed again, and extra DON susceptibility was described as a new trait. DON performance varied on the most sensitive cultivar between 0.32 and 143 mg/kg (mean 17.52 mg/kg) and on the most resistant genotype between 0.00 and 18.19 mg/kg (mean 1.87 mg/kg). Correlations between stability and resistance level are r = 0.85 for FHB, 0.78 for FDK, and 0.88 for DON, all at a significance level of p = 0.001. The very close correlation between FDK and DON contamination (r = 0.81, p = 0.001) proves that control of DON contamination needs appropriate resistance. In the breeding program evaluation of FDK is the most important, and then DON will be decided. Variety registration must be updated;otherwise no improvement on the field will occur.

Inoculation with arbuscular mycorrhizal fungi improves seedlings growth of two sahelian date palm cultivars (<i>Phoenix dactylifera</i>L., cv. Nakhla hamra and cv. Tijib) under salinity stresses

This study presents an analysis of the impact of mycorrhizal inoculation on growth under salt stress of date palms cultivars Nakhla hamra (NHH) and Tijib known in the Sahel for their earliness in flowering and fruiting. The seedlings were grown in a greenhouse on a sandy substrate watered to field capacity every two days and were subjected to increasing levels of NaCl (0, 1, 2, 4, 6, 8 and 16 g·L-1) and then inoculated with 5 strains of Glomus (G. aggregatum, G. intraradices, G. verriculosum, G. mosseae, G. fasciculatum). The experimental design was a randomized complete block with three factors (cultivars: Tijib and Nakhla Hamra x seven levels of NaCl concentrations x six levels of inoculum). The results showed that in the absence of NaCl, G. verriculosum significantly enhanced shoot growth: 33.5 cm against 30.3 cm in the control and roots growth: 81.5 cm against 78 cm in NHH, while in Tijib, the growth is stimulated by Glomus fasciculatum: 33.8 cm against 32.7 cm for stems and 90 cm against 86 cm for the roots of inoculated plants and controls. In contrast, in the presence of NaCl 8 g·L-1, NHH has a better growth in the presence of G. intraradices: 37.3 cm against 30.6 cm for stems and 77 cm against 73 for roots, while Tijib grows better in the presence of G. fasciculatum with respectively 31.9 cm against 31.7 cm and 51.27 cm against 51.6 cm for stems and roots of inoculated plants and controls. Biochemical analysis revealed that changes in levels of proline depend on the cultivar, the mycorrhizal strain used and concentrations of NaCl applied. These results open the prospect of using mycorrhizal fungi to improve the productivity of palm trees in the Sahel.

Effect of Dual Inoculation of Arbuscular Mycorrhiza and <i>Rhizobium</i>on the Chlorophyll, Nitrogen and Phosphorus Contents of Pigeon Pea (<i>Cajanus cajan</i>L.)

The pot experiments were conducted in the Department of Life Science and Bioinformatics of Assam University, Silchar. The aim of the present study was to investigate the effect of dual inoculation of Arbuscular mycorrhiza (AM) (Glomus fasciculatum) and Rhizobium on the chlorophyll, nitrogen and phosphorus contents of pigeon pea (Cajanus cajan L.). The results revealed an overall increase in chlorophyll, nitrogen and phosphorus contents in the inoculated plants than uninoculated ones. Maximum chlorophyll contents were recorded in the plants dually inoculated with Glomus fasciculatum and Rhizobium. The combined application of Glomus fasciculatum and Rhizobium also remarkably increased the nitrogen and phosphorus contents of pigeon pea. The dual inoculation with microsymbionts revealed synergistic effect. The results suggest that dual inoculation of Glomus fasciculatum and Rhizobium have the potential to enhance the chlorophyll, nitrogen and phosphorus contents of pigeon pea.

Stress Inoculation Training on Cognitive Emotional Regulation: The Effect on Vulnerable Married Female Adolescents

Married female adolescents are the most vulnerable people that culturally marry with their parents’ permission in Iran. This study aimed to investigate the effectiveness of stress inoculation training (SIT) on cognitive emotional regulation (CER) in these women. The method of this research was semi-experiment with pretest and posttest. The statistical society was the married adolescent female students from Qom high schools (80 people). First, they were assessed by cognitive emotional regulation questionnaire to find the subjects under the CER cut of point (55 people). Then 30 participants were randomly selected and were equally divided into experimental and control groups. The entry criteria for samples were female married students between 17 and 19 from low socioeconomic income. The experimental group received 8 sessions of SIT training while there was no intervention for control group. Results from MANCOVA analysis showed that there were significant differences between groups on cognitive emotional regulation in post-test. The data of pretest were the covariate factor. Finding suggests SIT is effective for cognitive emotional regulation in vulnerable married female adolescents. In addition, this training method elevates positive emotional strategies, which correlate with planning, focusing and organizing the emotions. In contrast, except self and the others blaming, negative emotional strategies differed slightly.

Influence of Cross-Inoculation on Groundnut and Bambara Groundnut-<i>Rhizobium</i>Symbiosis: Contribution to Plant Growth and Yield in the Field at Sarh (Chad) and Ngaoundere (Cameroon)

In the context of sustainable research aiming at improving seed yield and maintaining soil fertility, a study on cross-inoculation of groundnut (Arachis hypogaea L.) and Bambara groundnut (Vigna subterranean (L.) Verd.) with rhizobia strains from four crop legumes was carried out at Sarh (Chad) and Ngaoundere (Cameroon). The experiment was conducted in each site following a randomized complete block design with 6 treatments known as the control, and 5 cross-inoculation formulations (RA, RN, RS, RV and MR), each of which was replicated thrice. Results obtained show that cross-inoculation contributed to the improvement of growth (plant sizes and biomasses) of the two crop legumes, as well as their seed yield at harvest. The enhanced yield expressed in kg/ha varied from 9.83% to 63.73% for groundnut and 72.71% for Bambara groundnut. These findings suggest that groundnut and Bambara groundnut do have a symbiotic affinity with rhizobia from other crop legumes. Whereas Groundnut, Cowpea, Soybean, Bambara groundnut rhizobia (GR, CR, SR, BR) alone, and the fourth in a mixture (RM) could be used to help improving groundnut seed yields;this mixture would not be indicated for intensive cultivation of Bambara groundnut later.

Low-Density Co-Inoculation with Bradyrhizobium japonicum SAY3-7 and Streptomyces griseoflavus P4 Promotes Plant Growth and Nitrogen Fixation in Soybean Cultivars

Inoculation density has a marked effect on nodulation and N fixation in soybean (Glycine max L.). Therefore, we conducted this study to determine the optimal inoculation density of Bradyhizobium japonicum SAY3-7 (SAY3-7) and Streptomyces griseoflavus P4 (P4) for plant growth, nodulation, and N fixation, and to investigate the effect of co-inoculation on selected soybean cultivars, using the optimal inoculation density. Nitrogen fixation, in terms of an acetylene reduction activity value, was measured using a flame ionization gas chromatograph. In this study, low-density single inoculation with P4 (105 or 106 cells mL-1) was associated with the highest plant biomass, compared with normal- and high-density single inoculation with P4 (107 or 108 cells mL-1). Moreover, low-density single or co-inoculations with SAY3-7 and/or P4 produced the highest nodule biomass and highest nitrogenase activity, compared with single or dual inoculation at other inoculation densities. Therefore, we evaluated low-density co-inoculation with P4 and SAY3-7, at the rate of 105 cells mL-1, on selected soybean cultivars. Low-density co-inoculation increased the plant biomass, compared with un-inoculated plants. The effects of single and co-inoculation on nodulation did not differ significantly for any of the cultivars, except “Yezin-9” in the first experiment and “Shan Seine” in the second experiment. Low-density inoculation with both bacteria increased N fixation by 15% - 75% for seven of the cultivars in the first experiment and by 15% - 39% for three of the cultivars in the second experiment, compared with single inoculation with SAY3-7. Based on the overall results, we concluded that low-density co-inoculation with P4 and SAY3-7 gave improved plant growth and N fixation.

Pathogenic Effects of Cloned Genomic DNA of Porcine Circovirus-like Virus P1 on Neonatal Mice via Different Inoculation Routes

[Objective] The paper was to explore the pathogenicity of cloned genomic DNA of porcine circovirus-like virus Pl to neonatal mice via different inoculation routes （brain, liver and muscle）. [Method] Cloned genomic DNA of P1 was inoculated to neonatal mice via different routes of brain, liver and muscle. Tissues of heart, liver, spleen, lung, kidney and brain were taken from neonatal mice at 7, 14 and 21 d post inoculation, re- spectively. Pl in various tissues were qualitatively and quantitatively detected by using ordinary PCR and quantitative real-time PCR. Meanwhile, histopathological changes were analyzed. [Result] Pl was detected in neonatal mice inoculated through three different routes. The viral load of tis- sues at 7 d post inoculation was significantly higher than those at 14 and 21 d post inoculation. Moreover, muscle inoculation led to the highest viral load in all tissues of neonatal mice. [Conclusion] Pl infection caused different degrees of pathological damage to heart, liver, lung, kidney and brain in neonatal mice.

Microstructure of partially remelted billet of AM60 alloy prepared with self-inoculation method

The billets of AM60 alloy, prepared with self-inoculation method, were partially remelted into semisolid state.Effects of process parameters on remelting microstructure of semisolid billet were investigated.Experimental results show that the solid particles obtained with self-inoculation method are in smaller grain size and globular shape after partial remelting, compared with those prepared with other casting methods.In the optimized process conditions, the average size of solid particles of partially remelted billet is 65 μm, and the shape factor is 1.12.The process parameters, i.e.pouring temperature, addition amount of self-inoculants, and the slope angle of multi-stream mixing cooling channel have influence on the microstructure of partially remelted billet.The optimized temperature is from 680 °C to 700 °C, addition amount of self-inoculants is between 5% and 7% (mass fraction), slope angle of multi-stream mixing cooling channel is between 30° and 45°, with which the dendritic microstructure of as-cast billet can be avoided, and the size of solid particles of remelted billet is reduced.

Effect of leachate recycling and inoculation on the biochemical characteristics of municipal refuse in landfill bioreactors

Activity development of key groups of enzymes involved in municipal refuse decomposition was measured in laboratory landfill bioreactors with and without leachate recycling and inoculation for about 210 days. The results showed that the enzymes (amylase, protease, cellulase, lipase and pectinase) were present in fresh refuse but at low values and positively affected by leachate recycling and refuse inoculation. The total average of cellulase activity in digesters D3 operated with leachate recycling but no inoculation, D4 and D5 operated with leachate recycling and inoculation was much higher than that in digesters D1 and D2 without leachate recycling and inoculation by 88%—127%, 117%—162% and 64%—98%. The total average of protease activity was higher in digester D4 than that in digesters D1, D2, D3 and D5 by 63%, 39%, 24% and 24%, respectively, and the positive effect of leachate recycling and inoculation on protease activity of landfilled refuse mainly was at the first two months. The total average of amylase activity was higher in digesters D3, D4 and D5 than that in digesters D1 and D2 by 83%—132%, 96%—148% and 81%—129%. During the early phase of incubation, the stimulatory effect of inoculation on lipase activity was measured, but refuse moisture was the main factor affecting lipase activity of landfilled refuse. The inoculation, initial and continuous inoculation of microorganisms existing in leachate, was the mainly stimulatory factor affecting pectinase activity of landfilled refuse.

Research on immune effect of two gene vaccines containing brZPC′and brLDHC_4′when in combined inoculation

ZPC and LDHC_4 play a key role in the process of recognition between sperm and egg or sperm movement,respectively.In this study,partial cDNA sequences of ZPC and LDH-C_4 of Microtus branditi(brZPC and brLDHC_4,respectively) were cloned by RT-PCR,and directly inserted into pCR3.1 vector to construct two gene vaccines(pCR3.1-brZPC' and pCR3.1-brLDHC'_4).pCR3.1-brZPC' and pCR3.1-brLDHC,' could express corresponding proteins in transiently transfected CHO cells.The adult female BALB/c mice were inoculated with the recombinant vaccine alone on in combination.The immunized mouse can produce specific antibody that recognizes the corresponding recombinant protein expressed by BL21 in vitro.Moreover,antibodies produced by combinedly immunized mouse were specific and direct,with no inhibitory effect between two vaccines observed when in combined inoculation.The test of cytokines indicated that the expression of IFNγin pCR3.1-brZPC'- and combinedly inoculated mouse increased obviously and the expression of IL2 in pCR3.l-brLDHC'_4- and combinedly inoculated mouse increased obviously,while the expression of IL4 in pCR3.1-brZPC,pCR3.l-brLDHC'_4 and combinedly inoculated group increased obviously.It was suggested that the combined inoculation with pCR3.1-brZPC' and pCR3.l-brLDHC'_4 could induce both humoral immune response and CTL response.In some sense,the combined inoculation may achieve a better contraceptive effect.The results also showed that,when used alone or in combination,these two recombinant vaccines did not do much harm to the follicular development of immunized mouse.So the combined inoculation with these two recombinant vaccines could be a better way to immunocontraception.This study may provide a theoretical basis for the following tests on antifertility in vivo.

The Effect of Fusarium Inoculation and Fungicide Application on Concentrations of Flavonoids(Apigenin,Kaempferol,Luteolin,Naringenin,Quercetin,Rutin,Vitexin)in Winter Wheat Cultivars

Grain of 30 winter wheat cultivars was screened for the content of seven flavonoids (apigenin, kaempferol, luteolin, naringenin, quercetin, rutin, vitexin). In total, 90 samples were analyzed, belonging to three combinations: the control, samples inoculated with Fusarium culmorum, and samples inoculated with Fusarium culmorum and protected with fungicides (Prosaro, Topsin M). Analyzed flavonoids were detected in all tested samples. The highest concentrations were recorded for quercetin (512.9 mg/kg) and luteolin (458.4 mg/kg). Concentration of all compounds was the highest in the inoculated samples, while in the control and in the inoculated samples treated with fungicides their contents were significantly lower and similar, as confirmed by the statistical analysis conducted by multivariate methods. In most cases, significant correlations were obtained between individual flavonoids. Such correlations were observed for all flavonoids in samples covering all the three variants and almost all flavonoids in the inoculated samples. The lowest number of correlations was recorded for samples treated with fungicides.

Influence of inoculation on cast iron machinability:Case studies

Machinability can sometimes be difficult to predict and be impacted by different characteristics of the castings.Inoculation,a key step in foundry process,is well-known to be a powerful tool to adjust the characteristics of castings in both grey and ductile irons.Some metallurgical cases were investigated to understand different machinability behaviors in correlation to their metallographic characteristics.Thus,two examples taken from grey iron processes are analyzed to illustrate how inoculation is required to adjust characteristics of iron castings,especially the modification of graphite characteristics and the prevention of micro-shrinkage,both parameters are well-known to have an impact on iron machinability.The study also illustrates the importance of the ratio Mn/S to guarantee the presence of manganese sulfides in the matrix,beneficial for iron machinability.

Strategy Role of Mycorrhiza Inoculation on Osmotic Pressure, Chemical Constituents and Growth Yield of Maize Plant Gown under Drought Stress

The present work was carried out to investigate the role of mycorrhiza inoculation at two harvesting stages (90-days and 30-days) of maize plants grown in pot experiment with different moisture content levels 100%, 70%, 50% and 20%. Drought stress tolerant in maize plant was varied in different organs of the same plants and also varied among different stage of plant development. The sensitivity of maize plants was related with reduction of root soluble sugar, shoot and root soluble protein at 30-days of plant harvesting, and soluble sugar and soluble protein in both organs of both harvesting stages. This related with reduction in OP and lowering of water uptake which induced a marked decrease in fresh and dry matter production in shoot and root of both harvesting stages. AM inoculation increase maize tolerant to drought stress presented in increasing growth parameters, chemical constituents and minerals contents compared with untreated plants. Proline content with AM inoculation was more or less unchanged in shoot of plant harvesting at 30-days and in root of plant harvesting at 90-days. However, a marked increase was induced in plant harvesting at 30-days and in shoot of plant harvesting at 90-days. Mycorrhiza inoculation induced a significant increase in OP value either compared with corresponding level or compared with control value 100% as in plant 30-days of harvesting or compared with control only as in plant harvesting after 90-days. AM infection with different moisture content levels measured by N-acetyl glucosamine content were not affected by drought stress. Results showed also that control roots contained N-acetyl glucosamine would be attributed to mycorrhiza and other fungi naturally present in soil.

Fungal inoculation induces agarwood in young Aquilaria malaccensis trees in the nursery

Fungi are often used to induce agarwood inAquilariatrees. This study was conducted to evaluate the effect of several fungi on agarwood formation over time in youngAquilaria malaccensis （Lam.） trees. Typical changes in the length and light intensity of the resulting discoloration were observed after three and six month periods following inoculation. Wood samples were observed microscopically and classified into several light intensity groups. The discoloration length was meas-ured longitudinally. The duration after inoculation affected the mean of discoloration length： the 6-month old sample （1.70 cm） had a wider discoloration zone when compared to the 3-month old sample （1.17 cm）. When measuring the discoloration intensity, a positive relationship with time was perceived. Digital images, captured using a camera-equipped microscope, revealed that wood samples collected after six months appeared to be 1.8-times darker than after three months. We concluded that time, not the species of any of the tested fungi, had significant effect on discoloration length and intensity. Gas chromatography/mass spec-trometry （GCMS） analysis of the 6-month old sample yielded some important agarwood compounds such as benzylacetone, anisylacetone, guaiene and palustrol. This demonstrates that the tested fungi have the ability to induce agarwood formation in nurseryA. malaccensis trees.

Effect of inoculation with arbuscular mycorrhizal fungi on the degradation of DEHP in soil

The effect of inoculation with arbuscular mycorrhizal(AM) fungi( Acaulospora lavis ) on the degradation of di(2 ethylhexyl) phthalate(DEHP) in soil was studies. Cowpea plants (Pigna sinensis) were used as host plants and grown in a specially designed rhizobox. The experimental results indicated that, both in sterile and non sterile soil, mycorrhizal colonization rates were much higher in the mycorrhizal plants than in the non mycorrhizal plants. Addition of 4 mg/kg DEHP slightly affected mycorrhizal colonization, but the addition of 100 mg/kg DEHP significantly decreased mycorrhizal colonization. DEHP degradation in the mycorrhizosphere(Ms) and hyphosphere(Hs), especially in the Hs, increased after inoculation with Acaulospora lavis . It is concluded that mycorrhizal hyphae play an important role in the plant uptake, degradation and translocation of DEHP. The mechanism might be attributed to increased numbers of bacteria and actinomycetes and activity of dehydrogenase, urease and acid phosphatase in the Ms and Hs by mycorrhizal fungi.