Plantshave evolvedvariousmechanismsto interact withmicroorganisms,which help them acquire nutrients from the soil and enhance their tolerance to environmental stresses.One of the most widespread mutualistic interactio...Plantshave evolvedvariousmechanismsto interact withmicroorganisms,which help them acquire nutrients from the soil and enhance their tolerance to environmental stresses.One of the most widespread mutualistic interactions is arbuscular mycorrhizal(AM)symbiosis,which is formed by 80%-90%of terrestrial plants in association with AM fungi.In AM symbiosis,plants acquire mineral nutrients from the fungi in exchange for fatty acids and sugars that are produced during photosynthesis(Jiang et al.,2017).展开更多
The symbiotic relationships between trees and different mycorrhizal fungi affect the biodiversity-ecosystem functioning relationships within forest communities,particularly across different strata from the understorey...The symbiotic relationships between trees and different mycorrhizal fungi affect the biodiversity-ecosystem functioning relationships within forest communities,particularly across different strata from the understorey to the overstorey.However,current research on this relationship has not yet reached a definitive conclusion.In this study,we used regression analyses and structural equation modelling based on a 9-ha mixed broadleaved-Korean pine(Pinus koraiensis)forest plot to explore the effects of different types of mycorrhizal fungi(arbuscular mycorrhizal(AM)and ectomycorrhizal(EM)fungi)on the relationship between tree species diversity and productivity.The study found that the dominance and productivity of AM species increased in the understorey with increasing soil nutrients,whereas the productivity of EM species declined despite increasing diversity.In the overstorey,the productivity of AM species continued to increase with increasing soil nutrients,while that of EM species decreased due to increased competition.As for diversity-productivity relationships(DPRs),in the understorey,both AM and EM tree species demonstrated a positive DPR,suggesting the presence of the niche complementarity effect.In the overstorey,AM species continue to exhibit positive DPR due to their competitive advantage in nutrient-rich environments.In contrast,EM species exhibit negative DPR due to increased competition or less efficient resource use.Additionally,slope influenced forest productivity indirectly by altering the accumulation and distribution of soil nutrients,thereby affecting species distribution and growth conditions.This indirect effect highlights the potential negative impact of slope on soil nutrients within forest ecosystems,as well as its influence on the relationships between biodiversity and ecosystem functions.The study reveals how AM and EM trees influence forest productivity through distinct adaptability and competitive strategies across different forest strata,with a particular emphasis on the strata-dependent effects of mycorrhizal association on DPRs.This finding offers a new perspective on how mycorrhizal types modulate the complex relationships between biodiversity and ecosystem functions across various strata in temperate forests.展开更多
Fencing for grazing exclusion is regarded as a traditional and effective method for the natural restoration of degraded alpine steppe,and it effectively promotes plant growth and enhances soil carbon stocks.Arbuscular...Fencing for grazing exclusion is regarded as a traditional and effective method for the natural restoration of degraded alpine steppe,and it effectively promotes plant growth and enhances soil carbon stocks.Arbuscular mycorrhizal fungi(AMF)are essential microorganisms in grassland that play a major role in plant-derived C translocation into the soil.However,the effects of fencing on AMF communities and their contributions to soil carbon sequestration are still unclear.In this study,alpine steppe areas with three different fencing durations(free grazing,medium-term fencing for 5-6 years and long-term fencing for more than 10 years)in the northern Tibetan Plateau were selected to explore the effects of grazing exclusion on AMF communities and their roles in soil carbon sequestration.The results showed that medium-and long-term fencing significantly increased both plant aboveground biomass and soil organic carbon(SOC)content.The AMF community composition varied significantly during different fencing durations,with a dramatic increase in the relative abundance of Glomus but a significant reduction in the relative abundance of Diversispora with longer fencing time.Medium-term fencing significantly increased AMF richness and the ShannonWiener index.Meanwhile,fencing significantly increased hyphal length density(HLD),glomalin-related soil protein(GRSP)and the proportion of macroaggregates(250-2,000μm),all of which contribute positively to SOC.Structural equation modeling revealed that fencing time positively influenced HLD and the AMF community composition,subsequently affecting T-GRSP,which was tightly correlated with SOC.Our findings suggest the potentially important contribution of AMF to SOC sequestration,so more attention should be paid to AMF during alpine steppe fencing,particularly for enhancing the efficiency of degraded grassland restoration efforts.展开更多
This experiment evaluated the effects of the mycorrhizal fungus Glomus mosseae,Azotobacter chroococcum bacteria,and Biochar on the characteristics of the root system,and yield of the cucumber plant,Cucumis sativus L.,...This experiment evaluated the effects of the mycorrhizal fungus Glomus mosseae,Azotobacter chroococcum bacteria,and Biochar on the characteristics of the root system,and yield of the cucumber plant,Cucumis sativus L.,for this purpose,experiment designed:the first factor is a combination of Mycorrhizae(M)at 35 g plant-1,Azotobacter(A)15 ml plant-1 with a microbial density of 2.2,and three concentrations(0,5,10%)of Biochar sprayed on the plant.The results of the research demonstrated that using mycorrhizae,Azotobacter bacteria,and phosphate rock with half the mineral recommendation(MAR)and spraying Biochar at a concentration of 10%gave the highest rate of infection of the roots with mycorrhizae,amounting to 80%,and the highest dry weight of the root system reached 84.53 g.The highest number of total bacteria was 8.74 log Cfu g m-1 of soil,the highest plant height reached 375.0 cm,the highest dry weight of the shoot reached 101.66 g plant-1,and the highest yield for the greenhouse was 4.501 ton greenhouse-1,followed by the treatment of adding Mycorrhiza with phosphate rock and half the mineral recommendation(MR)with Biochar at a concentration of 10%,then treatment with the addition of mycorrhizae with Azotobacter bacteria with half the mineral recommendation(AR)with 10%of Biochar.It is possible to eliminate half of the mineral recommendation by using these fertilizers,reduce the harmful impact of pollution on the environment and enhance sustainability in agriculture.展开更多
The mutualistic symbiotic system formed by clumping arbuscular mycorrhizal fungi(AMF)and plants can remediate heavy metal-contaminated soils.However,the specific mechanisms underlying the interaction between AMF and i...The mutualistic symbiotic system formed by clumping arbuscular mycorrhizal fungi(AMF)and plants can remediate heavy metal-contaminated soils.However,the specific mechanisms underlying the interaction between AMF and inter-root microbial communities,particularly their impact on organic phosphorus(P)cycling,remain unclear.This study investigated the gene regulation processes involved in inter-root soil phosphorus cycling in wetland plants,specifically Iris tectorum,following inoculation with AMF under varying concentrations of chromium(Cr)stress.Through macro-genome sequencing,we analyzed the composition and structure of the inter-root soil microbial community associated with Iris tectorum under greenhouse pot conditions.The results demonstrated significant changes in the diversity and composition of the inter-root soil microbial community following AMF inoculation,with Proteobacteria,Actinobacteria,Chloroflexi,Acidobacteria,and Bacteroidetes being the dominant taxa.Under Cr stress,species and gene co-occurrence network analysis revealed that AMF promoted the transformation process of organic phosphorus mineralization and facilitated inorganic phosphorus uptake.Additionally,network analysis of functional genes indicated strong aggregation of(pstS,pstA,pstC,TC.PIT,phoR,pp-gppA)genes,which collectively enhanced phosphorus uptake by plants.These findings shed light on the inter-root soil phosphorus cycling process during the co-remediation of Cr-contaminated soil by AMF-Iris tectorum symbiosis,providing valuable theoretical support for the application of AMF-wetland plant symbiosis systems to remediate heavy metal-contaminated soil.展开更多
Nutrient acquisition through symbiotic ectomycorrhizal fungi is carbon(C)costly but fundamental for plant growth,community,and ecosystem functioning.Here,we examined the functions of roots and mycorrhiza with respect ...Nutrient acquisition through symbiotic ectomycorrhizal fungi is carbon(C)costly but fundamental for plant growth,community,and ecosystem functioning.Here,we examined the functions of roots and mycorrhiza with respect to nutrient uptake after artificially inducing C limitation-seven months after girdling of an ectomycorrhizal tree,Pinus taeda.Root physiological activity(measured as root nitrogen content and root exudation)declined after girdling and was accompanied with 110%and 340%increases in mycorrhizal colonization and extramatrical hyphal length,respectively.Fungi colonizing roots switched to a community characterized by higher C efficiency(lower C cost)of nutrient acquisition(CENA,the amount of nutrient acquisition per unit C cost)and lower network complexity,indicating a tradeoff between CENA and stability of the fungal community.Root transcriptome analysis suggested a shift in metabolic pathways from a tricarboxylic acid cycle decomposition of carbohydrate to lipid biosynthesis to maintain closer associations with mycorrhiza for nutrient cycling after the girdling.By integrating multi-level evidence,including root transcriptome,fungal composition,and network complexity data,we demonstrate an increased dependence on mycorrhiza for nutrient acquisition under the C limitation condition,which is likely due to a shift to fungal community with higher CENA at the cost of lower stability.展开更多
[Objective] The purpose was to study the effects of different arbuscular mycorrhizal fungi strains（AMF）on the mineral nutrition and antioxidant enzymes of Chrysanthemum morifolium.[Method] The pot experiment was con...[Objective] The purpose was to study the effects of different arbuscular mycorrhizal fungi strains（AMF）on the mineral nutrition and antioxidant enzymes of Chrysanthemum morifolium.[Method] The pot experiment was conducted in the greenhouse,C.morifolium ＇Jinba＇ was inoculated with five kinds of AMF,N,P,K,malondial dehyde（MDA）content,as well as the superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT） activity in roots,leaves and petals of C.morifolium were measured at seedling and flowering stages.[Result] The G.i,G.e and G.m treatments could promote mineral nutrient absorption,increase N,P,K content in roots,leaves and petals of C.morifolium compared with the control without inoculation.The G.d、G.e and G.m treatments could significantly reduce MDA content in roots and petals,thus alleviating membrane permeability and lipid peroxidation.The G.i treatments could also improve the SOD,POD and CAT activities of C.morifolium,thereby increasing the capability of scavenging oxygen free radicals.[Conclusion] According to the comprehensive analysis,G.i was screened out as the best strain to improve mineral nutrition and antioxidant enzyme activities of C.morifolium.展开更多
[Objective] This study aimed to investigate the effects of arbuscular mycor-rhizal fungi （AMF） on growth of upland rice under soil Pb contamination. [Method] Using potting method, the effects of Glomus mosseae on th...[Objective] This study aimed to investigate the effects of arbuscular mycor-rhizal fungi （AMF） on growth of upland rice under soil Pb contamination. [Method] Using potting method, the effects of Glomus mosseae on the growth of Oryzal sati-va L. under different soil Pb concentrations （0, 300, 600 mg/kg） were investigated. [Result] According to the results, the mycorrhizal colonization rate of upland rice in-oculated with Glomus mosseae was significantly reduced （P〈0.05） with the increase of Pb concentration in soil. Compared with non-inoculation treatment, inoculation of arbuscular mycorrhizal fungi significantly improved the biomass of upland rice and Pb concentration of upland rice roots with addition of 300 mg/kg Pb but significantly reduced Pb concentration of upland rice shoots, which was consistent with the re-duced R/S （P〈0.05）; with addition of 600 mg/kg Pb, inoculation of arbuscular mycor-rhizal fungi significantly improved the biomass of upland rice roots （P〈0.05） but sig-nificantly reduced Pb concentration of upland rice shoots and roots （P〈0.05）; there was no significant difference in R/S between inoculation treatment and non-inocula-tion treatment. [Conclusion] This study indicated that inoculating Glomus mosseae under certain Pb concentrations could to some extent al eviate the toxic effects of Pb on Oryzal sativa L.展开更多
[Objective] The research aimed to study the mycorrhizal formation in the offspring tissue culture seedling bottle of Pinus elliottii with Lecanosticta acicola resistance.[Method] The mycorrhizal formation of Pinus ell...[Objective] The research aimed to study the mycorrhizal formation in the offspring tissue culture seedling bottle of Pinus elliottii with Lecanosticta acicola resistance.[Method] The mycorrhizal formation of Pinus elliottii regenerated plant in vitro was studied,and the growth condition of regenerated plant was observed.[Result] The culture substrate and the inoculation amount of mycorrhizal fungi had the big influence on the mycorrhizal formation in vitro.After the root primordia were induced by Pinus elliottii caespitose shoots,it was best to transplant in the perlite substrate and inoculate Pisolithus tinctorius,which was favorable for the mycorrhizal formation.When the two blocks of Pisolithus tinctorius were inoculated in the perlite medium,the mycorrhizal formation rate reached 84.4%.The dichotomous branching short root was the most,and 12.49 roots were formed in every main root.The mycorrhizal formation improved the survival rate of regenerated plant domestication transplantation.The mycorrhizal regenerated plant grew well in the phytotron,and the root system was developed.[Conclusion] The research provided the basis for improving the survival rate of Pinus elliottii tissue culture regenerated plant with Lecanosticta acicola resistance.展开更多
[Objective] This study aimed to investigate the effect of arbuscular mycor-rhizal fungi on upland rice oxidative stress induced by Cu and Pb contamination in soil. [Method] The upland rice seeds were sowed in pots, in...[Objective] This study aimed to investigate the effect of arbuscular mycor-rhizal fungi on upland rice oxidative stress induced by Cu and Pb contamination in soil. [Method] The upland rice seeds were sowed in pots, in which the soil was previously mixed with a certain amount of Glomus mosseae and 0, 100 and 200 mg/kg Cu, or 0, 300 and 600 mg/kg Pb. In the control treatment, Glomus mosseae was inactivated before mixed into the soil. Then, the physiological and chemical properties of the aboveground parts of rice plants were measured at mature stage. [Result] Compared with the control treatment （NM）, Glomus mosseae （GM） treat-ment inhibited the POD, CAT and SOD activity while increased the soluble protein content under 100 mg/kg Cu and 300 mg/kg Pb treatment, improved the POD and CAT activity and soluble protein content while decreased SOD activity under 200 mg/kg Cu. SOD and POD activity showed no significant difference between NM and GM treatment under 600 mg/kg Pb, but the CAT activity was enhanced and soluble protein content was decreased. [Conclusion] This study wil provide theoretical refer-ence for bioremediation of soil heavy metal pol ution.展开更多
Diversity of arbuscular mycorrhizal fungi(AMF) was investigated in a field that had received long-term fixed ferti-lization(LFF) for 26 years.There were a total of 12 treatments in triplicates with different amounts o...Diversity of arbuscular mycorrhizal fungi(AMF) was investigated in a field that had received long-term fixed ferti-lization(LFF) for 26 years.There were a total of 12 treatments in triplicates with different amounts of manure,urea,calcium phosphate,and potassium chloride.Rhizosphere soil samples of maize and wheat grown in the experimental field in Shandong Province,China,were collected in September 2003 and May 2004,respectively.Arbuscular mycorrhizal fungal spores were isolated and identified using morphological characters.Mycorrhizal colonization percentage,spore density(SD),species richness(SR),relative abundance(RA),and Shannon-Weiner index(SWI) were determined.Nineteen recognized species of AMF belonging to 5 genera were identified.Long-term fixed fertilization significantly influenced colonization percentage,SR,SD,and species diversity of AMF.The adaptability of AMF to soil fertility was different among species.Species richness and SD of AMF in maize and wheat rhizosphere soils were the highest in the nonferti-lization treatment(control) and lowest in the high manure + high nitrogen treatment(M2N2).The SWI decreased as the fertilization level increased except in the low manure treatment(M1) on maize.Compared with the other treatments,Treatment M2N2 significantly reduced SD of Glomus,and the high manure + low nitrogen treatment(M2N1) significantly retarded sporulation of Scutellospora.Manure treatments stimulated sporulation of Glomus mosseae.Spore density of G.mosseae was higher in the high nitrogen + phosphorus + potassium treatment(N2PK) than in the high nitrogen + phosphorus treatment(N2P) and the high nitrogen + potassium treatment(N2K).The SD of S.pellucida was higher in Treatment N2K than Treatments N2PK and N2P.In conclusion,long-term fixed fertilization,especially with high levels of manure and N,decreased SR,SD,and colonization and changed the species composition of AMF.展开更多
Arbuscular mycorrhizal fungi （AMF） are essential functional microbiology in natural ecosystems. It is very important to research community composition and di- versity of AMF for achieving sustainable development of ...Arbuscular mycorrhizal fungi （AMF） are essential functional microbiology in natural ecosystems. It is very important to research community composition and di- versity of AMF for achieving sustainable development of ecosystems. The paper described several methods of researching the diversity of AMF, especially for molecular techniques, reviewed the application status of these methods in AMF research, and pointed out that the effective combination of morphological and molecular methods could better reveal the biodiversity and ecological functions of AMF in natural ecosystems.展开更多
The effects of arbuscular mycorrhizal fungi（AMF） Glomus mosseae on the responses to elevated O3 in growth and nutrition of snap bean（Phaseolus vulgaris L.cv Guangzhouyuan） were investigated.Exposure was conducted ...The effects of arbuscular mycorrhizal fungi（AMF） Glomus mosseae on the responses to elevated O3 in growth and nutrition of snap bean（Phaseolus vulgaris L.cv Guangzhouyuan） were investigated.Exposure was conducted in growth chambers by using three O3 concentrations（20（CF）,80（CFO1） and 120 nL/L（CFO2）;8 hr/day for 75 days）.Results showed that elevated O3 slightly impacted overall mycorrhizal colonization,but significantly decreased the proportional frequency of hypha and increased the proportional frequency of spores and vesicles,suggesting that O3 had significant effects on mycorrhizal structure.Elevated O3 significantly decreased yield,dry mass and nutrient contents（N,P,K,Ca and Mg） in both non-mycorrhizal and mycorrhizal plants.However,significant interactive effects were found in most variables due to that the reduction by O3 in the mycorrhizal plants was less than that in the non-mycorrhizal plants.Additionally,AMF increased the concentrations of N,P,Ca,and Mg in shoot and root.It can be concluded that AMF alleviated detrimental effects of increasing O3 on host plant through improving plant nutrition and growth.展开更多
The effects of inoculum forms (single-spore, multi-spores, or colonized root pieces) and host plants (Nicotiana tabacum L., Sorghum sudanense (Piper) Stapf, and Trifolium repens L.) on the development and inoculum pot...The effects of inoculum forms (single-spore, multi-spores, or colonized root pieces) and host plants (Nicotiana tabacum L., Sorghum sudanense (Piper) Stapf, and Trifolium repens L.) on the development and inoculum potential (IP) of the arbuscular mycorrhizal fungi (AMF) :Glo-mus macrocarpum Tul & Tul, donuis mosseae (Nicol & Gerd.) Gerdemann & Trappe, Glomus ver-siforme (Karsten) Berch, and Sclerocystis sinu/osa Gerdemann & Bakhi cultured in pots were investigated. The lag phase of treatment with 50 spores or 0.5 g (fresh weight) of colonized root pieces was 4 weeks, much shorter than that of the treatment with 1 spore (8 weeks); the value of IP (VIP) and percentage of root colonization (PRC) of the former were greater than those of the latter. Only on the early stages of colonization was there difference between the 50 spores and the 0.5 g (fresh weight) of colonized root piece inoculation treatments. The EP per plant inoculated with 0.5 g (fresh weight) of colonized root pieces of AMF was greater than that of the other two treatments except G. versiforme on Nicotiana tabacum, while the PRC of the plants inoculated with 50 spores and 0.5 g (fresh weight) of colonized root pieces of AMF was higher than that of the 1 spore inoculation after 10 weeks. Trie VIP of AMF on Trifolium repens was significantly higher than that on the other two hosts. The VIP of G. mosseae, G. versiforme, and S. sinuosa was respectively greater than that of G. macrocarpum. This suggested that different species of AMF produced different VIP of the inoculum . Nicotiana tabacum was much better than the other host plants which used to be inoculated with single spore, and to produce inocula of AMF.展开更多
Previous studies documented that most desert plants can be colonized by arbuscular mycorrhizal （AM） fungi, however, little is known about how the dynamics of AM fungi are related to ephemerals in desert ecosystems. ...Previous studies documented that most desert plants can be colonized by arbuscular mycorrhizal （AM） fungi, however, little is known about how the dynamics of AM fungi are related to ephemerals in desert ecosystems. The dynamics of AM fungi with desert ephemerals were examined to determine the effects of host plant life stages on the development of AM fungi. Mean colonization of ephemeral annual plants was 45% lower than that of ephemeral perennial plants. The colonizations were much higher in the early part of the growing season than in later parts, peaking at flowering times. The phenology of AM fungi in root systems varied among different ephem- erals. The density of AM fungal spores increased with the development of ephemeral annual plants, reached its maximum at flowering times, and then plateaued about 20 days after the aboveground senescence. A significant positive correlation was found between AM fungi spore density and biomass of ephemeral annual plants. The life cycles of AM fungi associated with desert ephemerals were very shod, being about 60-70 days. Soil temperature and water content had no direct influence on the development of AM fungal spores. We concluded that the development of AM fungi was in response to desert ephemeral phenology and life history strategy.展开更多
As common soil fungi that form symbioses with most terrestrial plants,arbuscular mycorrhizal(AM) fungi play an important role in plant adaptation to chromium(Cr) contamination.However,little information is available o...As common soil fungi that form symbioses with most terrestrial plants,arbuscular mycorrhizal(AM) fungi play an important role in plant adaptation to chromium(Cr) contamination.However,little information is available on the underlying mechanisms of AM symbiosis on plant Cr resistance.In this study,dandelion(Taraxacum platypecidum Diels.) was grown with and without inoculation of the AM fungus Rhizophagus irregularis and Cr uptake by extraradical mycelium(ERM) was investigated by a compartmented cultivation system using a Cr stable isotope tracer.The results indicated that AM symbiosis increased plant dry weights and P concentrations but decreased shoot Cr concentrations.Using the Cr stable isotope tracer technology,the work provided possible evidences of Cr uptake and transport by ERM,and confirmed the enhancement of root Cr stabilization by AM symbiosis.This study also indicated an enrichment of lighter Cr isotopes in shoots during Cr translocation from roots to shoots in mycorrhizal plants.展开更多
Straw return can be used to reduce fertilizer input and improve agricultural sustainability and soil health.However,how straw return and reduced fertilizer application affect beneficial soil microbes,particularly arbu...Straw return can be used to reduce fertilizer input and improve agricultural sustainability and soil health.However,how straw return and reduced fertilizer application affect beneficial soil microbes,particularly arbuscular mycorrhizal fungi(AMF),remains poorly understood.Here,we conducted a five-year field experiment in a rainfed maize field on the Loess Plateau of northwestern China.We tested four treatments with straw return combined with four nitrogen(N)application rates,i.e.,100%,80%,60%,and 0%of the common N application rate(225 kg N ha^(-1)year^(-1))in this region,and two reference treatments(full or no N application),with three replicates for each treatment.Mycorrhizal colonization was quantified and AMF communities colonizing maize roots were characterized using Illumina sequencing.Forty virtual taxa(VTs)of AMF were identified in root samples,among which VT113(related to Rhizophagus fasciculatus)and VT156(related to Dominikia gansuensis)were the predominant taxa.Both root length colonization and AMF VT richness were sensitive to N fertilization,but not to straw return;furthermore,both gradually increased with decreasing N application rate.The VT composition of the AMF community was also affected by N fertilization,but not by straw return,and the community variation could be well explained by soil available N and phosphorus concentrations.Additionally,60%,80%,and full N fertilization produced similar maize yields.Thus,our study revealed the response patterns of AMF to straw return and N fertilizer reduction and showed that straw return combined with N fertilizer reduction may be a promising practice to maintain mycorrhizal symbiosis concomitantly with crop productivity.展开更多
[Objective] The aim was to investigated the effects of seedling-cake with AMF on resistance of pepper （Capsicum annuum L.） to bacterial wilt. [Methods] A pot experiment was conducted to evaluate the dynamics of myco...[Objective] The aim was to investigated the effects of seedling-cake with AMF on resistance of pepper （Capsicum annuum L.） to bacterial wilt. [Methods] A pot experiment was conducted to evaluate the dynamics of mycorrhizal colonization, disease index, morbidity rate, control effect and several agronomic traits of mycorrhizal seedlings after inoculation with RS in two kinds of seeding-cakes with AMF. [Results] Two kinds of seedling-cakes formed steadily mycorrhizal colonization after inoculation, which enhanced disease-resistance and decreased morbidity rate and disease index in different degrees. What’s more, the performance of self-made seedling-cakes was obviously better than that of commercial seedling-cakes. [Conclusions] Self-made seedling-cakes with AMF have superior performance on bacterial wilt resistance of pepper, which should be made use of in other crops extensively.展开更多
[Objective] The aim was to study the effects of AMF on distribution of Pb in different chemical forms in rhizosphere soil of upland rice. [Method] A pot experiment was conducted to explore effects of AMF inoculation o...[Objective] The aim was to study the effects of AMF on distribution of Pb in different chemical forms in rhizosphere soil of upland rice. [Method] A pot experiment was conducted to explore effects of AMF inoculation on distribution of Pb in different forms in rhizosphere of rice (Oryzal sativa L.) with Pb in different concentrations (0, 300 and 600 mg/kg). [Result] With inoculation adopted, mycorrzhial colonization rate of upland rice under Pb pdlution root declined substantially with Pb increasing in soils (P<0.05). Compared with non-inoculation, rhizosphere pH significantly enhanced by inoculation; when Pb was at 300 mg/kg, glomalin content in soils improved significantly by inoculation; when Pb was at 600 mg/kg, glomalin content in soils declined substantially (P<0.05). In addition, inoculation significantly improved contents of Pb in exchangeable and organic forms, but lowered Pb in carbonate bound and Fe-Mn oxides bound forms (P<0.05). [Conclusion] The research indicated that AMF inoculation would change distribution of Pb in different forms in rhizosphere soils of upland rice.展开更多
Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating fac...Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain unclear.Based on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion effect.In addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,respectively.Surprisingly,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C decomposition.Furthermore,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root litter.These findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.展开更多
基金supported by the National Key R&D Program of China(2022YFF1001800)the National Natural Science Foundation of China(32088102)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0630103).
文摘Plantshave evolvedvariousmechanismsto interact withmicroorganisms,which help them acquire nutrients from the soil and enhance their tolerance to environmental stresses.One of the most widespread mutualistic interactions is arbuscular mycorrhizal(AM)symbiosis,which is formed by 80%-90%of terrestrial plants in association with AM fungi.In AM symbiosis,plants acquire mineral nutrients from the fungi in exchange for fatty acids and sugars that are produced during photosynthesis(Jiang et al.,2017).
基金financially supported by the Natural Science Foundation of Heilongjiang Province of China(No.TD2023C006)the Fundamental Research Funds for the Central Universities(No.2572022DS13).
文摘The symbiotic relationships between trees and different mycorrhizal fungi affect the biodiversity-ecosystem functioning relationships within forest communities,particularly across different strata from the understorey to the overstorey.However,current research on this relationship has not yet reached a definitive conclusion.In this study,we used regression analyses and structural equation modelling based on a 9-ha mixed broadleaved-Korean pine(Pinus koraiensis)forest plot to explore the effects of different types of mycorrhizal fungi(arbuscular mycorrhizal(AM)and ectomycorrhizal(EM)fungi)on the relationship between tree species diversity and productivity.The study found that the dominance and productivity of AM species increased in the understorey with increasing soil nutrients,whereas the productivity of EM species declined despite increasing diversity.In the overstorey,the productivity of AM species continued to increase with increasing soil nutrients,while that of EM species decreased due to increased competition.As for diversity-productivity relationships(DPRs),in the understorey,both AM and EM tree species demonstrated a positive DPR,suggesting the presence of the niche complementarity effect.In the overstorey,AM species continue to exhibit positive DPR due to their competitive advantage in nutrient-rich environments.In contrast,EM species exhibit negative DPR due to increased competition or less efficient resource use.Additionally,slope influenced forest productivity indirectly by altering the accumulation and distribution of soil nutrients,thereby affecting species distribution and growth conditions.This indirect effect highlights the potential negative impact of slope on soil nutrients within forest ecosystems,as well as its influence on the relationships between biodiversity and ecosystem functions.The study reveals how AM and EM trees influence forest productivity through distinct adaptability and competitive strategies across different forest strata,with a particular emphasis on the strata-dependent effects of mycorrhizal association on DPRs.This finding offers a new perspective on how mycorrhizal types modulate the complex relationships between biodiversity and ecosystem functions across various strata in temperate forests.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program,China(2019QZKK0304)the National Natural Science Foundation of China(31800380 and 31761123001-1)。
文摘Fencing for grazing exclusion is regarded as a traditional and effective method for the natural restoration of degraded alpine steppe,and it effectively promotes plant growth and enhances soil carbon stocks.Arbuscular mycorrhizal fungi(AMF)are essential microorganisms in grassland that play a major role in plant-derived C translocation into the soil.However,the effects of fencing on AMF communities and their contributions to soil carbon sequestration are still unclear.In this study,alpine steppe areas with three different fencing durations(free grazing,medium-term fencing for 5-6 years and long-term fencing for more than 10 years)in the northern Tibetan Plateau were selected to explore the effects of grazing exclusion on AMF communities and their roles in soil carbon sequestration.The results showed that medium-and long-term fencing significantly increased both plant aboveground biomass and soil organic carbon(SOC)content.The AMF community composition varied significantly during different fencing durations,with a dramatic increase in the relative abundance of Glomus but a significant reduction in the relative abundance of Diversispora with longer fencing time.Medium-term fencing significantly increased AMF richness and the ShannonWiener index.Meanwhile,fencing significantly increased hyphal length density(HLD),glomalin-related soil protein(GRSP)and the proportion of macroaggregates(250-2,000μm),all of which contribute positively to SOC.Structural equation modeling revealed that fencing time positively influenced HLD and the AMF community composition,subsequently affecting T-GRSP,which was tightly correlated with SOC.Our findings suggest the potentially important contribution of AMF to SOC sequestration,so more attention should be paid to AMF during alpine steppe fencing,particularly for enhancing the efficiency of degraded grassland restoration efforts.
文摘This experiment evaluated the effects of the mycorrhizal fungus Glomus mosseae,Azotobacter chroococcum bacteria,and Biochar on the characteristics of the root system,and yield of the cucumber plant,Cucumis sativus L.,for this purpose,experiment designed:the first factor is a combination of Mycorrhizae(M)at 35 g plant-1,Azotobacter(A)15 ml plant-1 with a microbial density of 2.2,and three concentrations(0,5,10%)of Biochar sprayed on the plant.The results of the research demonstrated that using mycorrhizae,Azotobacter bacteria,and phosphate rock with half the mineral recommendation(MAR)and spraying Biochar at a concentration of 10%gave the highest rate of infection of the roots with mycorrhizae,amounting to 80%,and the highest dry weight of the root system reached 84.53 g.The highest number of total bacteria was 8.74 log Cfu g m-1 of soil,the highest plant height reached 375.0 cm,the highest dry weight of the shoot reached 101.66 g plant-1,and the highest yield for the greenhouse was 4.501 ton greenhouse-1,followed by the treatment of adding Mycorrhiza with phosphate rock and half the mineral recommendation(MR)with Biochar at a concentration of 10%,then treatment with the addition of mycorrhizae with Azotobacter bacteria with half the mineral recommendation(AR)with 10%of Biochar.It is possible to eliminate half of the mineral recommendation by using these fertilizers,reduce the harmful impact of pollution on the environment and enhance sustainability in agriculture.
基金supported by 2024 Guizhou Basic Research Plan(Natural Science)Project,China(Foundation of Guizhou science cooperation-ZK[2024]General 490)the National Natural Science Foundation of China(No.31560107).
文摘The mutualistic symbiotic system formed by clumping arbuscular mycorrhizal fungi(AMF)and plants can remediate heavy metal-contaminated soils.However,the specific mechanisms underlying the interaction between AMF and inter-root microbial communities,particularly their impact on organic phosphorus(P)cycling,remain unclear.This study investigated the gene regulation processes involved in inter-root soil phosphorus cycling in wetland plants,specifically Iris tectorum,following inoculation with AMF under varying concentrations of chromium(Cr)stress.Through macro-genome sequencing,we analyzed the composition and structure of the inter-root soil microbial community associated with Iris tectorum under greenhouse pot conditions.The results demonstrated significant changes in the diversity and composition of the inter-root soil microbial community following AMF inoculation,with Proteobacteria,Actinobacteria,Chloroflexi,Acidobacteria,and Bacteroidetes being the dominant taxa.Under Cr stress,species and gene co-occurrence network analysis revealed that AMF promoted the transformation process of organic phosphorus mineralization and facilitated inorganic phosphorus uptake.Additionally,network analysis of functional genes indicated strong aggregation of(pstS,pstA,pstC,TC.PIT,phoR,pp-gppA)genes,which collectively enhanced phosphorus uptake by plants.These findings shed light on the inter-root soil phosphorus cycling process during the co-remediation of Cr-contaminated soil by AMF-Iris tectorum symbiosis,providing valuable theoretical support for the application of AMF-wetland plant symbiosis systems to remediate heavy metal-contaminated soil.
基金funded by the National Natural Science Foundation of China(32471824,32171746,42077450,31870522,31670550,42122054)the leading talents of basic research in Henan Province,the Scientific Research Foundation of Henan Agricultural University(30500854)+4 种基金Excellent Youth Creative Research Group Project in Henan Province(252300421002)Foreign Scientists Studio in Henan province(GZS2025011)the Funding for Characteristic and Backbone Forestry Discipline Group of Henan Province,Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control(2023B1212060002)Guangdong Basic and Applied Basic Research Foundation(2021B1515020082)the RUDN University Strategic Academic Leadership Program,Funding for Characteristic and backbone forestry discipline group of Henan Province and Research Funds for overseas returnee in Henan Province,China.We thank Editage Service in improving the English language.
文摘Nutrient acquisition through symbiotic ectomycorrhizal fungi is carbon(C)costly but fundamental for plant growth,community,and ecosystem functioning.Here,we examined the functions of roots and mycorrhiza with respect to nutrient uptake after artificially inducing C limitation-seven months after girdling of an ectomycorrhizal tree,Pinus taeda.Root physiological activity(measured as root nitrogen content and root exudation)declined after girdling and was accompanied with 110%and 340%increases in mycorrhizal colonization and extramatrical hyphal length,respectively.Fungi colonizing roots switched to a community characterized by higher C efficiency(lower C cost)of nutrient acquisition(CENA,the amount of nutrient acquisition per unit C cost)and lower network complexity,indicating a tradeoff between CENA and stability of the fungal community.Root transcriptome analysis suggested a shift in metabolic pathways from a tricarboxylic acid cycle decomposition of carbohydrate to lipid biosynthesis to maintain closer associations with mycorrhiza for nutrient cycling after the girdling.By integrating multi-level evidence,including root transcriptome,fungal composition,and network complexity data,we demonstrate an increased dependence on mycorrhiza for nutrient acquisition under the C limitation condition,which is likely due to a shift to fungal community with higher CENA at the cost of lower stability.
基金Supported by National Science and Technology Support Project(2006BAD07B05)Cooperation Project of Institute of Vegetables and Flowers,Chinese Academy of Agricultural Sciences,with Bei-jing Daxing District(2009-2011)~~
文摘[Objective] The purpose was to study the effects of different arbuscular mycorrhizal fungi strains（AMF）on the mineral nutrition and antioxidant enzymes of Chrysanthemum morifolium.[Method] The pot experiment was conducted in the greenhouse,C.morifolium ＇Jinba＇ was inoculated with five kinds of AMF,N,P,K,malondial dehyde（MDA）content,as well as the superoxide dismutase（SOD）,peroxidase（POD） and catalase（CAT） activity in roots,leaves and petals of C.morifolium were measured at seedling and flowering stages.[Result] The G.i,G.e and G.m treatments could promote mineral nutrient absorption,increase N,P,K content in roots,leaves and petals of C.morifolium compared with the control without inoculation.The G.d、G.e and G.m treatments could significantly reduce MDA content in roots and petals,thus alleviating membrane permeability and lipid peroxidation.The G.i treatments could also improve the SOD,POD and CAT activities of C.morifolium,thereby increasing the capability of scavenging oxygen free radicals.[Conclusion] According to the comprehensive analysis,G.i was screened out as the best strain to improve mineral nutrition and antioxidant enzyme activities of C.morifolium.
基金Supported by National Natural Science Foundation of China(81072989,40901149)Project for Promotion and Development of Private Education-Teaching and Educational Reform-Beijing City University "Construction of New Discipline-Water Supply and Drainage Engineering"~~
文摘[Objective] This study aimed to investigate the effects of arbuscular mycor-rhizal fungi （AMF） on growth of upland rice under soil Pb contamination. [Method] Using potting method, the effects of Glomus mosseae on the growth of Oryzal sati-va L. under different soil Pb concentrations （0, 300, 600 mg/kg） were investigated. [Result] According to the results, the mycorrhizal colonization rate of upland rice in-oculated with Glomus mosseae was significantly reduced （P〈0.05） with the increase of Pb concentration in soil. Compared with non-inoculation treatment, inoculation of arbuscular mycorrhizal fungi significantly improved the biomass of upland rice and Pb concentration of upland rice roots with addition of 300 mg/kg Pb but significantly reduced Pb concentration of upland rice shoots, which was consistent with the re-duced R/S （P〈0.05）; with addition of 600 mg/kg Pb, inoculation of arbuscular mycor-rhizal fungi significantly improved the biomass of upland rice roots （P〈0.05） but sig-nificantly reduced Pb concentration of upland rice shoots and roots （P〈0.05）; there was no significant difference in R/S between inoculation treatment and non-inocula-tion treatment. [Conclusion] This study indicated that inoculating Glomus mosseae under certain Pb concentrations could to some extent al eviate the toxic effects of Pb on Oryzal sativa L.
基金Supported by State Forestry Administration"948"Item(2011-4-69)~~
文摘[Objective] The research aimed to study the mycorrhizal formation in the offspring tissue culture seedling bottle of Pinus elliottii with Lecanosticta acicola resistance.[Method] The mycorrhizal formation of Pinus elliottii regenerated plant in vitro was studied,and the growth condition of regenerated plant was observed.[Result] The culture substrate and the inoculation amount of mycorrhizal fungi had the big influence on the mycorrhizal formation in vitro.After the root primordia were induced by Pinus elliottii caespitose shoots,it was best to transplant in the perlite substrate and inoculate Pisolithus tinctorius,which was favorable for the mycorrhizal formation.When the two blocks of Pisolithus tinctorius were inoculated in the perlite medium,the mycorrhizal formation rate reached 84.4%.The dichotomous branching short root was the most,and 12.49 roots were formed in every main root.The mycorrhizal formation improved the survival rate of regenerated plant domestication transplantation.The mycorrhizal regenerated plant grew well in the phytotron,and the root system was developed.[Conclusion] The research provided the basis for improving the survival rate of Pinus elliottii tissue culture regenerated plant with Lecanosticta acicola resistance.
基金Supported by National Natural Science Foundation of China(41101246)Private Education Development Project(892-34)~~
文摘[Objective] This study aimed to investigate the effect of arbuscular mycor-rhizal fungi on upland rice oxidative stress induced by Cu and Pb contamination in soil. [Method] The upland rice seeds were sowed in pots, in which the soil was previously mixed with a certain amount of Glomus mosseae and 0, 100 and 200 mg/kg Cu, or 0, 300 and 600 mg/kg Pb. In the control treatment, Glomus mosseae was inactivated before mixed into the soil. Then, the physiological and chemical properties of the aboveground parts of rice plants were measured at mature stage. [Result] Compared with the control treatment （NM）, Glomus mosseae （GM） treat-ment inhibited the POD, CAT and SOD activity while increased the soluble protein content under 100 mg/kg Cu and 300 mg/kg Pb treatment, improved the POD and CAT activity and soluble protein content while decreased SOD activity under 200 mg/kg Cu. SOD and POD activity showed no significant difference between NM and GM treatment under 600 mg/kg Pb, but the CAT activity was enhanced and soluble protein content was decreased. [Conclusion] This study wil provide theoretical refer-ence for bioremediation of soil heavy metal pol ution.
基金supported by the National Natural Science Foundation of China (No.30871737)the Natural Science Foundation of Qingdao,China (No.08-1-3-20-jch)
文摘Diversity of arbuscular mycorrhizal fungi(AMF) was investigated in a field that had received long-term fixed ferti-lization(LFF) for 26 years.There were a total of 12 treatments in triplicates with different amounts of manure,urea,calcium phosphate,and potassium chloride.Rhizosphere soil samples of maize and wheat grown in the experimental field in Shandong Province,China,were collected in September 2003 and May 2004,respectively.Arbuscular mycorrhizal fungal spores were isolated and identified using morphological characters.Mycorrhizal colonization percentage,spore density(SD),species richness(SR),relative abundance(RA),and Shannon-Weiner index(SWI) were determined.Nineteen recognized species of AMF belonging to 5 genera were identified.Long-term fixed fertilization significantly influenced colonization percentage,SR,SD,and species diversity of AMF.The adaptability of AMF to soil fertility was different among species.Species richness and SD of AMF in maize and wheat rhizosphere soils were the highest in the nonferti-lization treatment(control) and lowest in the high manure + high nitrogen treatment(M2N2).The SWI decreased as the fertilization level increased except in the low manure treatment(M1) on maize.Compared with the other treatments,Treatment M2N2 significantly reduced SD of Glomus,and the high manure + low nitrogen treatment(M2N1) significantly retarded sporulation of Scutellospora.Manure treatments stimulated sporulation of Glomus mosseae.Spore density of G.mosseae was higher in the high nitrogen + phosphorus + potassium treatment(N2PK) than in the high nitrogen + phosphorus treatment(N2P) and the high nitrogen + potassium treatment(N2K).The SD of S.pellucida was higher in Treatment N2K than Treatments N2PK and N2P.In conclusion,long-term fixed fertilization,especially with high levels of manure and N,decreased SR,SD,and colonization and changed the species composition of AMF.
基金Supported by National Natural Science Foundation of China (30900963)Natural Science Foundation of Yunnan Province (2009ZC072M)Scientific Research Pogram of Yunnan Provincial Educaition Department (09Z0038)~~
文摘Arbuscular mycorrhizal fungi （AMF） are essential functional microbiology in natural ecosystems. It is very important to research community composition and di- versity of AMF for achieving sustainable development of ecosystems. The paper described several methods of researching the diversity of AMF, especially for molecular techniques, reviewed the application status of these methods in AMF research, and pointed out that the effective combination of morphological and molecular methods could better reveal the biodiversity and ecological functions of AMF in natural ecosystems.
基金supported by the National Natural Science Foundation of China(No.40701180,30670387)the Chinese Universities Scientific Fund(No.ZZ1106, ZD0904)the Project of Beijing Key Discipline and State Key Laboratory of Urban and Regional Ecology
文摘The effects of arbuscular mycorrhizal fungi（AMF） Glomus mosseae on the responses to elevated O3 in growth and nutrition of snap bean（Phaseolus vulgaris L.cv Guangzhouyuan） were investigated.Exposure was conducted in growth chambers by using three O3 concentrations（20（CF）,80（CFO1） and 120 nL/L（CFO2）;8 hr/day for 75 days）.Results showed that elevated O3 slightly impacted overall mycorrhizal colonization,but significantly decreased the proportional frequency of hypha and increased the proportional frequency of spores and vesicles,suggesting that O3 had significant effects on mycorrhizal structure.Elevated O3 significantly decreased yield,dry mass and nutrient contents（N,P,K,Ca and Mg） in both non-mycorrhizal and mycorrhizal plants.However,significant interactive effects were found in most variables due to that the reduction by O3 in the mycorrhizal plants was less than that in the non-mycorrhizal plants.Additionally,AMF increased the concentrations of N,P,Ca,and Mg in shoot and root.It can be concluded that AMF alleviated detrimental effects of increasing O3 on host plant through improving plant nutrition and growth.
基金Supported by International foundation for Science (IFS)National Natural Science Foundation of China.
文摘The effects of inoculum forms (single-spore, multi-spores, or colonized root pieces) and host plants (Nicotiana tabacum L., Sorghum sudanense (Piper) Stapf, and Trifolium repens L.) on the development and inoculum potential (IP) of the arbuscular mycorrhizal fungi (AMF) :Glo-mus macrocarpum Tul & Tul, donuis mosseae (Nicol & Gerd.) Gerdemann & Trappe, Glomus ver-siforme (Karsten) Berch, and Sclerocystis sinu/osa Gerdemann & Bakhi cultured in pots were investigated. The lag phase of treatment with 50 spores or 0.5 g (fresh weight) of colonized root pieces was 4 weeks, much shorter than that of the treatment with 1 spore (8 weeks); the value of IP (VIP) and percentage of root colonization (PRC) of the former were greater than those of the latter. Only on the early stages of colonization was there difference between the 50 spores and the 0.5 g (fresh weight) of colonized root piece inoculation treatments. The EP per plant inoculated with 0.5 g (fresh weight) of colonized root pieces of AMF was greater than that of the other two treatments except G. versiforme on Nicotiana tabacum, while the PRC of the plants inoculated with 50 spores and 0.5 g (fresh weight) of colonized root pieces of AMF was higher than that of the 1 spore inoculation after 10 weeks. Trie VIP of AMF on Trifolium repens was significantly higher than that on the other two hosts. The VIP of G. mosseae, G. versiforme, and S. sinuosa was respectively greater than that of G. macrocarpum. This suggested that different species of AMF produced different VIP of the inoculum . Nicotiana tabacum was much better than the other host plants which used to be inoculated with single spore, and to produce inocula of AMF.
基金funded by the National Natural Science Foundation of China (30770341)the International Fund for Agricultural Development (the WATERCOPE project,I-R-1284)
文摘Previous studies documented that most desert plants can be colonized by arbuscular mycorrhizal （AM） fungi, however, little is known about how the dynamics of AM fungi are related to ephemerals in desert ecosystems. The dynamics of AM fungi with desert ephemerals were examined to determine the effects of host plant life stages on the development of AM fungi. Mean colonization of ephemeral annual plants was 45% lower than that of ephemeral perennial plants. The colonizations were much higher in the early part of the growing season than in later parts, peaking at flowering times. The phenology of AM fungi in root systems varied among different ephem- erals. The density of AM fungal spores increased with the development of ephemeral annual plants, reached its maximum at flowering times, and then plateaued about 20 days after the aboveground senescence. A significant positive correlation was found between AM fungi spore density and biomass of ephemeral annual plants. The life cycles of AM fungi associated with desert ephemerals were very shod, being about 60-70 days. Soil temperature and water content had no direct influence on the development of AM fungal spores. We concluded that the development of AM fungi was in response to desert ephemeral phenology and life history strategy.
基金supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No.KZCX2-YW-BR-17)the National Natural Science Foundation of China(No.41101246)the State Key Laboratory of Urban and Regional Ecology, Research Center of Eco-Environmental Sciences,Chinese Academy of Sciences(No.SKLURE2008-1-03)
文摘As common soil fungi that form symbioses with most terrestrial plants,arbuscular mycorrhizal(AM) fungi play an important role in plant adaptation to chromium(Cr) contamination.However,little information is available on the underlying mechanisms of AM symbiosis on plant Cr resistance.In this study,dandelion(Taraxacum platypecidum Diels.) was grown with and without inoculation of the AM fungus Rhizophagus irregularis and Cr uptake by extraradical mycelium(ERM) was investigated by a compartmented cultivation system using a Cr stable isotope tracer.The results indicated that AM symbiosis increased plant dry weights and P concentrations but decreased shoot Cr concentrations.Using the Cr stable isotope tracer technology,the work provided possible evidences of Cr uptake and transport by ERM,and confirmed the enhancement of root Cr stabilization by AM symbiosis.This study also indicated an enrichment of lighter Cr isotopes in shoots during Cr translocation from roots to shoots in mycorrhizal plants.
基金financially supported by the National Natural Science Foundation of China(Nos.32060260,32171579,and 32360548)。
文摘Straw return can be used to reduce fertilizer input and improve agricultural sustainability and soil health.However,how straw return and reduced fertilizer application affect beneficial soil microbes,particularly arbuscular mycorrhizal fungi(AMF),remains poorly understood.Here,we conducted a five-year field experiment in a rainfed maize field on the Loess Plateau of northwestern China.We tested four treatments with straw return combined with four nitrogen(N)application rates,i.e.,100%,80%,60%,and 0%of the common N application rate(225 kg N ha^(-1)year^(-1))in this region,and two reference treatments(full or no N application),with three replicates for each treatment.Mycorrhizal colonization was quantified and AMF communities colonizing maize roots were characterized using Illumina sequencing.Forty virtual taxa(VTs)of AMF were identified in root samples,among which VT113(related to Rhizophagus fasciculatus)and VT156(related to Dominikia gansuensis)were the predominant taxa.Both root length colonization and AMF VT richness were sensitive to N fertilization,but not to straw return;furthermore,both gradually increased with decreasing N application rate.The VT composition of the AMF community was also affected by N fertilization,but not by straw return,and the community variation could be well explained by soil available N and phosphorus concentrations.Additionally,60%,80%,and full N fertilization produced similar maize yields.Thus,our study revealed the response patterns of AMF to straw return and N fertilizer reduction and showed that straw return combined with N fertilizer reduction may be a promising practice to maintain mycorrhizal symbiosis concomitantly with crop productivity.
基金Supported by Hunan Natural Science Foundation(11JJ5015)Department of Science and Technology of Hunan Province(2011FJ3050)~~
文摘[Objective] The aim was to investigated the effects of seedling-cake with AMF on resistance of pepper （Capsicum annuum L.） to bacterial wilt. [Methods] A pot experiment was conducted to evaluate the dynamics of mycorrhizal colonization, disease index, morbidity rate, control effect and several agronomic traits of mycorrhizal seedlings after inoculation with RS in two kinds of seeding-cakes with AMF. [Results] Two kinds of seedling-cakes formed steadily mycorrhizal colonization after inoculation, which enhanced disease-resistance and decreased morbidity rate and disease index in different degrees. What’s more, the performance of self-made seedling-cakes was obviously better than that of commercial seedling-cakes. [Conclusions] Self-made seedling-cakes with AMF have superior performance on bacterial wilt resistance of pepper, which should be made use of in other crops extensively.
文摘[Objective] The aim was to study the effects of AMF on distribution of Pb in different chemical forms in rhizosphere soil of upland rice. [Method] A pot experiment was conducted to explore effects of AMF inoculation on distribution of Pb in different forms in rhizosphere of rice (Oryzal sativa L.) with Pb in different concentrations (0, 300 and 600 mg/kg). [Result] With inoculation adopted, mycorrzhial colonization rate of upland rice under Pb pdlution root declined substantially with Pb increasing in soils (P<0.05). Compared with non-inoculation, rhizosphere pH significantly enhanced by inoculation; when Pb was at 300 mg/kg, glomalin content in soils improved significantly by inoculation; when Pb was at 600 mg/kg, glomalin content in soils declined substantially (P<0.05). In addition, inoculation significantly improved contents of Pb in exchangeable and organic forms, but lowered Pb in carbonate bound and Fe-Mn oxides bound forms (P<0.05). [Conclusion] The research indicated that AMF inoculation would change distribution of Pb in different forms in rhizosphere soils of upland rice.
基金supported by China Postdoctoral Science Foundation(No.2023M741742)the National Key R&D Program of China(No.2023YFD1501600)+1 种基金Jiangsu Funding Program for Excellent Postdoctoral Talent,China(No.2023ZB122)the National Natural Science Foundation of China(No.32371626)。
文摘Plant roots and their associated mycorrhizal fungi critically mediate the decomposition of soil organic carbon(C),but the general patterns of their impacts over a broad geographical range and the primary mediating factors remain unclear.Based on a synthesis of 596 paired observations from both field and greenhouse experiments,we found that living roots and/or mycorrhizal fungi increased organic C decomposition by 30.9%,but low soil nitrogen(N)availability(i.e.,high soil C:N ratio)critically mitigated this promotion effect.In addition,the positive effects of living roots and/or mycorrhizal fungi on organic C decomposition were higher under herbaceous and leguminous plants than under woody and non-leguminous plants,respectively.Surprisingly,there was no significant difference between arbuscular mycorrhizal fungi and ectomycorrhizal fungi in their effects on organic C decomposition.Furthermore,roots and/or mycorrhizal fungi significantly enhanced the decomposition of leaf litter but not root litter.These findings advance our understanding of how roots and their symbiotic fungi modulate soil C dynamics in the rhizosphere or mycorrhizosphere and may help improve predictions of soil global C balance under a changing climate.
