Arbuscular Mycorrhizal Fungal Density Research Articles

Density and Phenotypic Diversity of Arbuscular Mycorrhizal Fungi in a Revegetated Tailing Storage Facility in Ghana

Arbuscular Mycorrhizal fungi (AMF) aid the establishment of vegetation on stressed soils as they contribute to soil ecological functions as well as improvement in plant growth. Understanding the mycorrhizal diversity and density within an area is an important step in harnessing the immense benefits of mycorrhiza. This study assessed the diversity and density of AMF in a revegetated tailing storage facility in Ghana. A balanced hierarchical sampling scheme with 4 stages and 72 sampling points was used over four sampling periods. Seventeen AMF spore types from nine genera (Acaulospora, Claroideoglomus, Diversispora, Gigaspora, Glomus, Racocetra, Rhizophagus, Septoglomus and Scutellospora) and five families (Acaulosporaceae, Claroideoglomeraceae, Diversisporaceae, Gigasporaceae and Glomeraceae) were isolated and identified from the samples. The density of spores varied between 24 and 817; 21 and 303; 21 and 321; and 24 and 875 spores 100 g-1 dry tailing solids respectively for the four sampled periods. The spore densities for the control samples also varied between 85 and 307; 65 and 248; 90 and 321 and 70 and 287 spores 100 g-1 dry soil for the respective sampling periods. Recorded spore densities varied significantly within sampling locations (p = 0.000) and between sampling periods (p = 0.000). The density and diversity of the AMF found in this study were relatively high and may have contributed significantly to the revegetation of the storage facility. These findings are important pointers for the adoption of mycorrhization in vegetation establishment and ultimately rehabilitation of decommissioned tailings storage facilities in Ghana. Further studies should however be done to determine how the various vegetation types found on the TSF affect AMF diversity and density.

Assessing differential land use impacts on soil quality: A method based on log-response ratios and polygonal projections

Soil quality indices (SQI) used for assessing soil degradation are often developed using additive scoring functions. However, these SQI may lack reference values for interpreting their outputs and the capacity to differentiate changes in specific variables. To overcome these limitations, this study introduces SQI using Log Response Ratios (LRR) as measures of size effects caused by land use in physical, chemical, and microbiological soil quality indicators. LRR vectors projected 2D polygons with condensed change measures along their perimeters. This method was tested in andosols within the southeastern region of Antioquia, Colombia. These soils were subjected to contrasting stages of degradation determined by the extent of A-horizon removal due to land use practices. This study shows that mining and agriculture have detrimental effects on soil organic carbon and water contents, and that size effects vary significantly between land uses (p < 0.05). Microbiological features also exhibit distinct size effects, such as populations of culturable mesophilic bacteria and fungi, microbial basal respiration, spore density of arbuscular mycorrhizal fungi (AMF), their diversity, and total glomalin-related soil proteins (p < 0.05). The SQI proposed exhibited a negative correlation with SQI computed from scoring additive functions either considering the entire dataset (R2 = 0.87) or a minimum dataset (R2 = 0.90). This approach underscores the utility of using LRR geometrical analysis to assess global soil quality differences among land uses (p < 0.01), offering a visual, quantifiable representation of the effects of each land use over specific soil quality indicators.

Spore Density of Arbuscular Mycorrhizal Fungi in the Forest Soils of Kagoshima Prefecture

Spore Density of Arbuscular Mycorrhizal Fungi in the Forest Soils of Kagoshima Prefecture

Observation of Arbuscular Mycorrhizal Fungi (AMF) Spores in Organic and Conventional Coffee Farms

In this study, AMF colonization in the soil of coffee farms adopting organic and conventional agricultural practices was observed in two different sites. Variation of AMF types, density, and inoculation in the coffee roots was observed throughout the wet filtration method. Although we found the infection of the root in coffee roots from both organic and conventional farming systems, in the organic farming system, we found higher variation in AMF types than in the conventional farming system. Sustainable land management is crucial to maintain the existence of soil microorganisms that are important for plant growth.

Dodder parasitism limited the effect of arbuscular mycorrhizal fungi on litter decomposition

Effects from parasitism and parasitic litter input can affect the decomposition of litter, but the mechanism is unclear. We hypothesized that the decomposition of litter produced by the holoparasite Cuscuta australis is promoted more strongly by arbuscular mycorrhizal fungi (AMF) than the litter of its host Bidens pilosa and that parasitism by C. australis can indirectly suppress the ability of AMF to promote the decomposition of host B. pilosa litter. We conducted two container experiments to compare the effect of AMF on the decomposition of 15N-labelled C. australis and B. pilosa litter filled in litter bags and to test the effect of C. australis parasitism on the decomposition of B. pilosa litter by AMF. The percentage of 15N remaining, AMF hyphal density, and enzyme activity in the litter bags were measured, and the bacterial communities in the litter bags were also tested using 16S amplicon sequencing. We found that the amount of 15N that remained in the bags with C. australis litter was significantly higher than that in the bags with B. pilosa litter. AMF significantly decreased the remaining 15N and changed the bacterial community in bags with B. pilosa litter but did not significantly affect these factors in the bags with C. australis litter. The bacterial diversity, AMF hyphal density and the abundance of several genes related to the N cycle, including assimilatory nitrate reduction and anaerobic ammonium oxidation, in the bags with C. australis litter were significantly lower than those in the bags with host litter. Parasitism significantly reduced the hyphal density of AMF, increased the 15N that remained in litter bags, and decreased the abundance of several genes related to the N cycle, such as those involved in anaerobic ammonium oxidation. Our results indicate that AMF plays a key role in the parasitism and litter effects of parasitic plants on soil nutrient cycling.

Nitrogen addition overrides the effects ofStellera chamaejasmelitter on the growth ofLeymus chinensisand its associated mycorrhizal fungi

AbstractRapid spread and growth of plants that are poisonous to animals produce large amounts of plant litter in degraded grasslands. Nitrogen (N) input may promote the growth of these poisonous plants and alter the rhizosphere microbes and arbuscular mycorrhizal fungi (AMF) in particular. However, it is unclear how poisonous plant litter affects the growth of palatable plants and their associated AMF in the rhizosphere and whether and how N deposition may mediate these effects. A greenhouse experiment was performed to test the combined effects of litter addition of a poisonous plant, Stellera chamaejasme, and N addition on the growth of a dominant grass, Leymus chinensis, AMF characteristics and soil properties. Litter addition significantly increased the ramet number and aboveground biomass of L. chinensis and soil available phosphorus (AP) concentration and decreased the spore density of AMF. However, the interaction of both treatments had no significant effects on traits of L. chinensis and AMF properties. Stellera chamaejasme litter positively affected L. chinensis by increasing AP and negatively affected AMF by combining balanced changes in soil nutrients and litter-induced allelopathic compositions. High N addition may alleviate soil N limitation and inhibit litter decomposition, thus overriding the litter’s effects on L. chinensis and AMF. These findings imply that it is necessary to objectively and comprehensively evaluate the ecological functions of poisonous plants beyond their harmful effects on livestock. Simultaneously, N deposition should be an indispensable factor in predicting the relationships between poisonous plants and edible plants in degraded grasslands.

Phosphorus Fractions and Arbuscular Mycorrhizal Fungi Communities in a Tropical Coarse-Textured Soil under Natural Forest and Para Rubber Ecosystems

Soil phosphorus (P) plays an essential role in rubber tree plantations that are rapidly and extensively being established in Southeast Asia. However, available information is quite limited on soil P fractions and arbuscular mycorrhizal fungi (AMF) in the tropical region. Herein, we investigated P fractions and AMF community under natural forest and rubber plantations at different ages of 5 years, 11 years, and 22 years in tropical coarse-textured soils from Thailand. The studied loamy sand soils were acidic (pH=5.0-5.7) with low available P concentrations (1.73-6.48 mg/kg). Data on the P fractions data revealed that the labile P (water-extractable Pi and NaHCO3-extractable Pi) and moderately labile P (NaOH0.1-extractable Po and HCl-extractable Pi) pools in rubber-growing soils were higher than those in the natural forest soil. Elevated values of these properties were substantial with increasing stand ages. The rubber monocropping systems declined in the density and diversity of AMF spores compared to the natural forest site. Glomus badium, Rhizophagus fasciculatus, Acaulospora Laevis, and Ambispora appendiculata were the most dominant and tolerant AMF species across the rubber stands (&gt;50% of the total species). The P fractions and AMF were correlated with soil labile-P forms. Soil labile and moderately P fractions were the important factors affecting the difference in AMF community. This study highlighted that long-term rubber plantations in tropical ecosystems promoted labile P fraction but demoted AMF density and diversity.

Density of Arbuscular Mycorrhizal Fungi and Nutrient Status of Soils in Selected Land Use Types and Soil Depths

Density of Arbuscular Mycorrhizal Fungi and Nutrient Status of Soils in Selected Land Use Types and Soil Depths

Combined inoculation with dark septate endophytes and arbuscular mycorrhizal fungi: synergistic or competitive growth effects on maize?

BackgroundEffects on maize were assessed of dual inoculation with arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) isolated from other plant species.MethodsSuspensions of DSE isolated from Stipa krylovii were prepared at different densities (2, 4, and 8 × 105 CFU mL− 1) and inoculated separately (AMF or DSE) or together (AMF + DSE), to explore their effects on maize growth.ResultsInoculation with AMF or medium and high densities of DSE and combined inoculation (AMF + DSE) increased plant above-ground growth and altered root morphology. Differences in plant growth were attributable to differences in DSE density, with negative DSE inoculation responsiveness at low density. AMF promoted plant above-ground growth more than DSE and the high density of DSE promoted root development more than AMF. Combined inoculation might lead to synergistic growth effects on maize at low density of DSE and competitive effects at medium and high DSE densities.ConclusionsAMF and DSE co-colonized maize roots and they had positive effects on the host plants depending on DSE density. These findings indicate the optimum maize growth-promoting combination of AMF and DSE density and provide a foundation for further exploration of potentially synergistic mechanisms between AMF and DSE in physiological and ecological effects on host plants.

Phosphorus fertilization rather than nitrogen fertilization, growing season and plant successional stage structures arbuscular mycorrhizal fungal community in a subtropical forest

Soil arbuscular mycorrhizal (AM) fungi were monitored in a 4-year experiment of nitrogen (N) and phosphorus (P) fertilization in three growing seasons (April, August, and November) under two successional stages (young and mature) in a subtropical forest of China. AM fungal extra-radical hyphal density was significantly affected by fertilization, season, and interactions between fertilization and season and between forest stage and season, but not by forest stage. The spore density of AM fungi was significantly affected by forest stage and season, but not by fertilization. Totally, 160 operational taxonomic units (OTUs) of AM fungi have been identified at a 97% sequence similarity level using Illumina MiSeq sequencing of the V4 region of the 18S rDNA. AM fungal Shannon diversity index, but not OTU richness, showed a positive response to P fertilization. The community composition of AM fungi was significantly influenced by P fertilization, but not by N fertilization, season, and forest stage. Phosphorus fertilization exhibited a negative impact on the relative abundance of the dominant Glomeraceae. This finding highlights that P availability has a strong effect on the community of AM fungi in the subtropical forest ecosystem.

Arbuscular mycorrhizal status of Erythrina brucei in different land use types in Ethiopia

Erythrina brucei is a leguminous tree commonly used in agro-forestry practices in southern and southwestern Ethiopia. It has desirable agro-forestry attributes that make it a good candidate for agro-forestry systems. However, there is a scarcity of information regarding species diversity and spore density of arbuscular mycorrhizal fungi (AMF) associated with E. brucei growing in different land use types. Therefore, this study was initiated to determine species diversity and richness in trap cultures of AMF associated with E. brucei growing in different geographic locations in various land use types of Ethiopia. Soil samples were collected from various E. brucei growing areas with different land use patterns. Trap culture was established using a portion of each soil sample by planting E. brucei as the host plant. AMF spore extraction was carried out in field and trap culture soils, and AMF species identification was done using spore morphology. Erythrina brucei root colonization with AMF structures was studied using trap culture, and AMF spore density in both field and trap culture soil samples was determined. A total of 11 AMF genera and 33 AMF species were recovered. The highest number of genera was recovered from forest land use type at Rebu Gebeya, followed by Adiskdam, live fence land use type. Glomus and Acaulospora were the dominant AMF genera covering 73% of the samples and contained 10 and 9 AMF species, respectively. All the soil samples contained indigenous AMF spore populations regardless of their origin and land use types. The highest mean AMF spore density in a field soil sample was recorded at a farmland in Bodite (280 spores 100 g−1 of dry soil), while the lowest was from Hossana (172 spores 100 g−1of dry soil). However, the highest mean AMF spore density in trap culture was detected from a farm land at Humbo (715 spores 100 g−1 of dry soil) and the lowest from Dhakallo (217 spores 100 g−1 of dry soil). Direct extraction of AMF from field soil samples showed lesser AMF spore density compared with trap culture in the same soil sample. All E. brucei root segments were colonized with the AMF structures, and the colonization status ranged from 34.4% to 49.1%. Both geographic location and land use type significantly affected AMF species richness (p < 0.05). Undisturbed land use types were characterized by high species richness. The soil pH and available phosphorus were negatively correlated to AMF spore density (p < 0.05), but AMF root colonization did not show any significant correlation. Moreover, significant correlations were also not observed between spore number and root colonization, and available phosphorus and root length colonization. We conclude that diverse and dominant AMF genera inhabited the rhizosphere of E. brucei, which can be used for the enhancement of host plant growth. To explore AMF species diversity and richness across geographic location and land use types in detail enhanced area coverage and the combination of both direct field soil and trap culture techniques are recommended.

Biodiversity Arbuscular Mycorrhizal Fungi in the Former Gold Mine Area in North Sumatra

This study aims to determine the diversity of arbuscular mycorrhizal fungi in the area of the former gold mine in North Sumatra. This research was conducted with 5 soil sampling points. The research method used began with calculating the percentage of root colonization, spores density of arbuscular mycorrhizal fungi and types of arbuscular mycorrhizal fungal spores. In addition, physical and chemical conditions of the soil are also measured. The results showed that the rate of root colonization was at moderate to high with an average rate of root colonization at 22.8%. The density of arbuscular mycorrhizal fungi spores in this study averaged 10/50 g of sample soil. the number of spores in this study belongs to the moderate category, however the characteristics of the study location show the uniqueness of its own area that makes the population of mycorrhizal types not too much. Spore types were found in 4 types with each Glomus and Acaulospora. The conclusion obtained that there was a symbiosis between fungi and plants in the former gold mining area in North Sumatra.

Levantamento de fungos micorrízicos arbusculares em associação a espécie vegetal Manihot esculenta Crantz

Cassava production in the state of Alagoas is mostly carried out by small rural producers who adopt little management technology, and who routinely do not replace nutrients due to the high cost of chemical inputs. In this agricultural production model, the knowledge and use of strategies that include natural biological processes in the soil, mainly of the microbiota present in this environment, such as arbuscular mycorrhizal fungi (AMF), can be presented as an alternative for biofertilization, since, Arbuscular mycorrhizae are symbiotic associations established between the roots of most plants and non-pathogenic fungi in the soil that have beneficial effects, which can improve plant growth and productivity and soil structure. Thus, the aim of this study was to evaluate the density of glomerospores and the native AMF genera present in the rhizosphere of cassava, Sergipana variety, as well as to determine mycorrhizal colonization in the evaluated culture. Soil collections were made in the cassava rhizosphere, at 90, 180, 270 and 360 days after planting (DAP). The average number of glomerospores in each treatment was evaluated at 90, 180, 270 and 360 DAP, and the main AMF genera present, and an evaluation of mycorrhizal colonization of the roots at 360 DAP was performed. Cassava cultivation showed an increase of approximately 174.46% at 360 DAP, showing a significant difference in the density of AMFs when compared to the 90 DAP period. The genera Diversispora sp, Entrophospora sp, Acaulospora sp, Scutellospora sp, and Racocetra sp. in cultivation, and a positive result for mycorrhizal colonization, with a 61% rate of colonization of the roots of the evaluated species.

Effects of crop rotation on enhanced occurrence of arbuscular mycorrhizal fungi and soil carbon stocks of lowland paddy fields in seasonaly dry tropics

The impacts of crop rotation systems on the arbuscular mycorrhizal fungal (AMF) spore density, mycorrhizal colonization of rice roots, soil C fractions and C stocks in seasonally dry climatic zone of Sri Lanka were examined in Rice–Soybean (RS) and Rice–Onion (RO) crop rotation systems during the subsequent rice cultivation season and, compared these with a rice monoculture, i.e. Rice–Rice (RR). The study also examined the correlations between AMF occurrence and soil carbon stocks. Results revealed that RS crop rotation system significantly enhances the occurrence of AMF spores in soil with a higher fraction of large sized spores, the total organic C (TOC), microbial biomass C (MBC), water soluble C (WSC), labile C and a high AMF colonization in rice roots in the subsequent rice cultivation season. The diversity of AMF morphospecies were also the highest in RS. Reduction in AMF density in the soil in RR crop rotation system may be due to prolonged anaerobic conditions prevailed. The growth of onion has drastically reduced the AMF colonization in rice and soil C contents. Soil carbon stocks showed positive correlations with % root colonization and AMF spore number in soil. Thus, the study confirmed that C stocks in paddy soils can be improved by intercropping with AMF supporting plants like soya bean. This is the first report that shows positive correlations of AMF sporulation and % root colonization in lowland rice with soil carbon stocks.

Arbusculer mycorrizal fungal investigation in the weeds of wheat field of Tehsil Tangi, District Charsadda, Khyber Pakhtunkhwa.

An investigation has been make about the Arbuscular Mycorrhizal Fungi (AMF) spore density in weeds plants with soil selected from the Tehsil Tangi. The spore density was observed in all weeds plants in the host growth stage. The maximum Arbuscular Mycorrhizal Fungi (AMF) spore density wasfound in Chenopodium album (93.00±74.02) and Scandix iberica (89.00±92.08) at vegetative stage. The Glomus species are dominant in the rhizosporic soil of weeds plants followed in Aculospora, and Sclerocystis. The lowest Glomus spore density are present in Fumariapureflora (10.67±15.89).The spore density of AMF had a strong positive correlation with soil PH and carbon is negative correlation with P content of the soil. Thehighest Vesicles are investigated in.Euphorbia heliscopia(14.33±9.5) and lowest in Circium arevesis (3.33±1.53) .Arbuscules was higher in Euphorbia heliscopia (18.67±18.72) and lowest in Circium arvensis (2.00±1.73). Highest External hyphae was found in Silene conidia (4.00±1.73) and lowest in Anagallus arrensis. Internal hyphae were in Rananculas maricates (6.33±5.13) and lowest in Melolotus indica(0.67±0.58). While totally absent in Brassica nigra (Brassicaece).

Response of arbuscular mycorrhizal fungal community in soil and roots to grazing differs in a wetland on the Qinghai-Tibet plateau.

Grazing as one of the most important disturbances affects the abundance, diversity and community composition of arbuscular mycorrhizal (AM) fungi in ecosystems, but the AM fungi in response to grazing in wetland ecosystems remain poorly documented. Here, we examined AM fungi in roots and soil in grazing and non-grazing plots in Zoige wetland on the Qinghai-Tibet plateau. Grazing significantly increased AM fungal spore density and glomalin-related soil proteins, but had no significant effect on the extra radical hyphal density of AM fungi. While AM fungal richness and community composition differed between roots and soil, grazing was found to influence only the community composition in soil. This study shows that moderate grazing can increase the biomass of AM fungi and soil carbon sequestration, and maintain the AM fungal diversity in the wetland ecosystem. This finding may enhance our understanding of the AM fungi in response to grazing in the wetland on the Qinghai-Tibet plateau.

CHARACTERIZATION OF RHIZOBIA AND ARBUSCULAR MYCORRHIZAL FUNGI IN AREAS IMPACTED BY GRAVEL MINING IN BRAZIL

ABSTRACT On-shore oil exploration is one of the main economic activities in the semiarid region (Caatinga biome) of the state of Rio Grande do Norte (RN), Brazil. Gravel mining is an activity associated with oil exploration that causes environmental impacts. Gravel is a base-material for constructions, such as roads and pumpjack bases. The areas of gravel mining and other decommissioned areas where the gravel has been deposited must be revegetated with species native to the biome at end of the activity in the site. An efficient strategy for revegetation of degraded areas has been the planting of leguminous species that can associate with rhizobia and arbuscular mycorrhizal fungi (AMF). Nevertheless, the impact of mining activities on the autochthonous populations of these microorganisms is unknown. The objective of the present work is to characterize the density of rhizobia and AMF spores in four areas impacted by the oil exploration in RN when compared to non-impacted adjacent areas. Gravel samples were collected in dry and rainy seasons in two mining areas: one in a pumpjack base, and one in a waste disposal area. Surface soil (topsoil) samples were collected in adjacent areas with native Caatinga vegetation. Assays were carried out to evaluate the most probable number (MPN) of rhizobia and to identify the type and density of arbuscular mycorrhizal fungi (AMF), using rhizobia trap plants Mimosa tenuiflora (Mart.) Benth. and Mimosa caesalpiniifolia Benth. The MPN of rhizobia was low in all areas, but higher in the rainy season. The highest amount and diversity of AMF spores were found in the dry season. Among the symbiotic microorganisms studied, the AMF presented lower densities in the evaluated areas when compared to those in the adjcent native vegetation areas, denoting the impact of this activity.

Arbuscular Mycorrhizal Fungal Communities Are Influenced by Host Tree Species on the Loess Plateau, Northwest China

Arbuscular mycorrhizal (AM) fungi can establish mutualistic symbioses with most terrestrial plants and therefore play a crucial role in the re-vegetation and rehabilitation of degraded ecosystems. Yet, little information is available on AM fungal communities associated with dominant tree species in the semi-arid region of the Loess Plateau, Northwest China. In this study, topsoil (0–20 cm) and subsoil (20–40 cm) samples were collected from the rhizosphere of five dominant tree species in northern Shaanxi Province, to investigate the distribution and diversity of their associated AM fungi. The tree species were Hippophae rhamnoides Linn., Juniperus communis L., Populus cathayana Rehd., Robinia pseudoacacia L., and Salix matsudana Koidz. In total, 24 AM fungal species of eight genera were isolated from the rhizosphere soil samples and identified based on their spore morphology. Funneliformis and Funneliformis monosporum were respectively the most abundant genus and species of AM fungi. The distribution and diversity of AM fungi differed among the five tree species and also between the two soil depths. Across different tree species, the spore density of AM fungi varied from 2.85 to 15.32 spores g−1 fresh soil, with a species richness of 3–7, Shannon–Wiener index of 0.81–1.08, and evenness index of 0.30–0.53. The mycorrhizal colonization rate had a significant negative correlation with both the Shannon-Wiener index and species richness, whereas it was positively correlated with the evenness index. Permutational multivariate analysis of variance, non-metric multidimensional scaling, and structural equation modeling revealed that tree species, rather than soil depth or its interactions with tree species, had significant effects on the composition of AM fungal communities. In conclusion, the distribution and diversity of AM fungi associated with the dominant tree species were mainly affected by host tree species identity in the semi-arid ecosystem. Claroideoglomus etunicatum (W.N. Becker &amp; Gerdemann) C. Walker &amp; A. Schüßler and Glomus reticulatum Bhattacharjee &amp; Mukerji appeared to be promising candidates for ecological restoration in the Loess Plateau region because of their adaptation to its semi-arid conditions with a broad spectrum of host tree species.

The effect of Rhizophagus irregularis on salt stress tolerance of Elaeagnus angustifolia roots

We assessed the effects of arbuscular mycorrhizal fungi (AMF) Rhizophagus irregularis inoculation on salt stress tolerance in roots of the drought-tolerant plant Elaeagnus angustifolia. We studied a plant growth index, spore density and hyphal length density of AMF, the Na+ contents and ultrastructure of root cells, as well as rhizosphere soil enzyme activities of mycorrhizal and non-mycorrhizal E. angustifolia seedlings under different salt stress. Under salt stress, growth of E. angustifolia with mycorrhizal inoculation was higher than that of non-inoculated treatments. The spore density and hyphal length density decreased significantly under salt stress in rhizosphere soil of mycorrhizal E. angustifolia seedlings (p < 0.05). The root cells of E. angustifolia seedlings inoculated with R. irregularis at 300 mmol L−1 salt had more organelles, greater integrity, and lower root Na+ contents than those of non-inoculated seedlings. In addition, the results showed notably higher activities of catalase, phosphatase, urease and saccharase in rhizosphere soil of the mycorrhizal seedlings in response to salinity compared to those of the non-mycorrhizal seedlings. Therefore, AMF inoculation could enhance salt stress tolerance in roots of E. angustifolia.

桉树种植对林地土壤丛枝菌根真菌群落结构及多样性的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 桉树种植对林地土壤丛枝菌根真菌群落结构及多样性的影响 DOI: 10.5846/stxb201804140855 作者: 作者单位: 华南农业大学,华南农业大学,华南农业大学,华南农业大学,华南农业大学,华南农业大学 作者简介: 通讯作者: 中图分类号: 基金项目: 国家林业局科技项目（AS-2017-01）；广东省林业厅项目（粤财农[2017]83号） Diversity and structure of the soil arbuscular mycorrhizal fungal community are altered by Eucalyptus plantations Author: Affiliation: South China agricultural University,South China agricultural University,South China agricultural University,South China agricultural University,South China agricultural University,South China Agruiculture University Fund Project: the Project of the Department of Forest of Guangdong Province（YUE CAI NONG [2017] No.83) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:桉树（Eucalyptus spp.）种植所产生的生态争议已受到广泛关注。丛枝菌根真菌（Arbuscular Mycorrhizal Fungi，AM真菌）是土壤微生物的重要组成部分，与根系共生后可促进植物的养分运输、提高植物逆境生存能力等。然而，桉树种植对土壤AM真菌群落结构和功能的影响尚不清楚。研究比较了次生林改种桉树后不同年限（2年/5年/10年）的土壤理化性质、AM真菌种类、群落组成及多样性的变化。结果表明，桉树种植显著改变了土壤理化性质，具体表现为2年生和10年生桉树林中土壤pH和有机碳显著降低（P < 0.05）；AM真菌的孢子密度在桉树林土壤中显著低于次生林土壤（其中在5年生土壤中最低）；AM真菌的种丰度随种植年份的增加逐渐下降，在10年生桉树林土壤中有所恢复；5年生桉树的菌根侵染率最高，10年生桉树侵染率最低。AM真菌群落组成和结构发生显著变化，优势种Funneliforms geosporus的丰度在2年生和10年生林地中显著降低；而Septoglomus deserticola的丰度在2年生和10年生林地中显著增加。另外，冗余分析（Redundancy analysis，RDA）结果表明，土壤AM真菌群落结构主要受土壤pH值（解释率：89.88%）变化的影响。研究揭示了次生林改种桉树林后土壤AM真菌的群落变化特征，为桉树林的栽培管理和环境修复提供了数据支撑。 Abstract:Eucalyptus plantations are controversial because of its complexed impacts on environments. Arbuscular mycorrhizal (AM) fungi in soil provide important ecological functions such as enhancing soil nutrient transportation and plant stress tolerance via symbiosis. Until recently, the influence of massive Eucalyptus planting on soil microbial communities, especially the AM fungi is yet to be investigated. Herein, we investigated into these effects by comparing the diversity and taxonomic composition of AM fungal community in soil between the secondary forest and Eucalyptus forests which involved two-, five-, and ten-year's plantations. Our results provided evidence that the practices of Eucalyptus plantations significantly changed soil properties (P < 0.05), e.g., the soil pH and soil organic carbon significantly decreased in the two- and ten-year's soil samples relative to the secondary forest. Importantly, spore density of AM fungi in soil declined by the Eucalyptus plantations, with the lowest level being observed in the five-year plantation. Species richness of AM fungi inclined to decrease within five years of Eucalyptus plantation, but recovered to a contain extent after ten years. In contrast, AM infection rate on the roots of Eucalyptus reached to the highest and lowest level in the five-year and ten-year plantation, respectively. Further, the composition and structure of AM fungi shifted significantly by Eucalyptus plantations. Noticeably, the dominant species Funneliformis geosporus and Septoglomus deserticola significantly decreased and increased in the two- and ten-year Eucalyptus plantations, respectively. Lastly, our redundancy analysis indicated that soil pH largely promoted the variation of the AM fungal community (explanation rate: 89.88%). Collectively, our study revealed the shifts of AM fungi in the soil of the secondary forest after the practices of Eucalyptus plantations, which is necessary to shed light onto the strategies of environment restoration in Eucalyptus plantations. 参考文献 相似文献 引证文献