Arbuscular mycorrhizal fungi associated with the Meliaceae on Hainan island, China

Species richness, spore density, frequency of occurrence, and relative abundance of AM fungi were determined in rhizosphere soil samples from nine tropical rainforest sites on Hainan island, south China, and the arbuscular mycorrhizal (AM) status of members of the Meliaceae was examined. All 28 plant taxa investigated (25 species including two varieties of 1 species and three varieties of another) were colonized by AM fungi. The mean proportion of root length colonized was 56% (range 10–95%). Vesicles were observed in 27 and hyphal coils in 26 of the 28 plant taxa. Mycorrhizas were of the Paris-type or intermediate-type, with no Arum-type mycorrhizas observed. Species richness of AM fungi varied from 3 to 15 and spore density from 46 to 1,499 per 100 g rhizosphere soil. Of 33 AM fungal taxa in five genera isolated and identified, 18 belonged to Glomus, 9 to Acaulospora, 1 to Entrophospora, 2 to Gigaspora, and 3 to Scutellospora. Acaulospora and Glomus were the dominant genera identified. Glomus claroideum was the taxon most commonly isolated, with a frequency of occurrence of 56.5% and relative abundance of 10.4%. A positive correlation was found between percentage of root length colonization and species richness. However, there was no correlation between spore density and percentage of root length colonized by AM fungi.     

Arbuscular mycorrhizal fungi associated with common pteridophytes in Dujiangyan,southwest China

The colonization and diversity of arbuscular mycorrhizal (AM) fungi associated with common pteridophytes were investigated in Dujiangyan, southwest China. Of the 34 species of ferns from 16 families collected, 31 were colonized by AM fungi. The mean percentage root length colonized was 15%, ranging from 0 to 47%. Nineteen species formed Paris-type and 10 intermediate-type AM. In two ferns, only rare intercellular non-septate hyphae or vesicles were observed in the roots and AM type could not be determined. Of the 40 AM fungal taxa belonging to five genera isolated from rooting-zone soils, 32 belonged to Glomus, five to Acaulospora, one to Archaeospora, one to Entrophospora, and one to Gigaspora. Acaulospora and Glomus were the dominant genera and Glomus versiforme was the most common species. The average AM spore density was 213 per 100 g air-dried soil and the average species richness was 3.7 AM species per soil sample. There was no correlation between spore density and percentage root length colonized by AM fungi.     

The diversity of arbuscular mycorrhizal fungi in the subtropical forest of Huangshan (Yellow Mountain), East-Central China

The world heritage of Huangshan is located in the east-central China. In order to obtain a better overview of biodiversity in Huangshan, we investigated the diversity of arbuscular mycorrhizal fungi in the soil of Huangshan. Forty-two rhizosphere soil samples were collected and 989 arbuscular mycorrhizal fungal spore samples were obtained using the wet-sieving method. Twenty-five species of arbuscular mycorrhizal fungi were identified from the collections. The species were of the genera Acaulospora (6 species), Entrophospora (1 species), Glomus (16 species) and Scutellospora (2 species). Acaulospora and Glomus were dominant at the study site. The arbuscular mycorrhizal fungi spore density ranged from 45 to 3,250 per 100 g soil (average 839), and the species richness of arbuscular mycorrhizal fungi ranged from 1 to 9 (average 4.2) per soil sample. Shannon–Wiener index and Simpson’s index were calculated to evaluate the arbuscular mycorrhizal fungal diversity. The diversity of arbuscular mycorrhizal fungal community in the subtropical forest of Huangshan may be the result of mutual selection between arbuscular mycorrhizal fungi and the ecological environment.     

A preliminary survey of the arbuscular mycorrhizal status of grassland plants in southern Tibet

We report for the first time the arbuscular mycorrhizal (AM) status of native plant species and AM fungal diversity in the grasslands of southern Tibet. A total of 51 soil samples were collected from the rhizospheres of the dominant plant species, and AM fungal structures were observed in 18 (82%) of 22 plant species examined. Vesicles and aseptate hyphae were the structures most frequently observed in the plant roots. After trap culture for 5 months, 25 AM fungal taxa were identified in the soil samples collected, of which nine belonged to Glomus, ten to Acaulospora, one to Entrophospora and five to Scutellospora. The frequency of occurrence of different genera and species varied greatly. Glomus was the dominant genus, and the most frequent and abundant species was Glomus mosseae. Over the whole sampling area, spore density in the rhizosphere soil of different host plant species ranged from 2 to 66 per 20 g air-dried soil. Overall AM fungal species richness was 2.10 and species diversity was 2.35. AM fungal diversity was also compared among the four different land use types (farmland and normal, disturbed and highly disturbed montane scrub grassland). Spore densities in the farmland and normal grassland were much higher than in the grasslands that had been degraded to varying degrees. The species richness in normal grassland was the highest of the four land use types examined. Species diversity varied from 1.99 to 0.94 and was highest in normal grassland, intermediate in degraded grassland and farmland, and lowest in the highly disturbed grassland.     

不同生境下川麦冬根围土壤丛枝菌根真菌多样性北大核心CSCD

采用高通量(Illumina Miseq)测序技术对栽培和野生2种生境下川麦冬根围的丛枝菌根(AM)真菌多样性和群落结构进行测定,并结合土壤理化因子进行相关性分析,以明确两种生境下川麦冬根围土壤AM真菌多样性和优势群落的分布特点,探讨AM真菌群落分布差异的驱动因子,为AM真菌应用于麦冬生产提供理论依据和技术支持。结果表明:(1)不同生境下川麦冬根围土壤中共鉴定出AM真菌3属10种,其中野生川麦冬根围土壤鉴定出的AM真菌3属7种,分别隶属于无梗囊霉属(Acaulospora)、多孢囊霉属(Diversispora)和球囊霉属(Glomus),而栽培环境下鉴定出AM真菌1属6种,隶属于球囊霉属。2个生境优势属均为球囊霉属。(2)不同生境下川麦冬根围AM真菌之间存在显著差异,野生生境下川麦冬根围土壤AM真菌多样性指数ACE和Shannon均显著高于人工栽培生境,而Simpson指数则相反。(3)相关性分析表明,AM真菌多样性指数及群落组成结构均与土壤理化因子存在相关性,其中全钾(TK)、全磷(TP)、全氮(TN)对AM真菌多样性指数和群落结构组成均存在显著影响。研究认为,不同生境下川麦冬根围AM真菌群落存在显著差异,球囊霉属为川麦冬互利共生的关键属,TK、TP、TN是不同生境川麦冬根围AM真菌群落差异的主要驱动因子。     

Arbuscular mycorrhizal and dark septate endophyte fungal associations in South Indian grasses

We examined arbuscular mycorrhizal (AM) and dark septate endophyte (DSE) fungal association in 50 south Indian grasses from four different sites. AM fungal diversity was also compared among the different sites. Forty-four of the 50 grasses examined had AM association and dual association with DSE fungi occurred in 25 grasses. We report for the first time AM and DSE fungal status in 23 and 27 grasses respectively. Arum-type AM morphology was the dominant occurring in 21 grasses with typical Paris-type colonization occurring in 6 grasses. AM morphology is reported for the first time in 35 grasses. Over the different sites, spore density in the soil ranged from 5–22 per 100 g air-dried soil. Spores of 11 AM fungal taxa were isolated from the soil samples of grasses of which nine belonged to Glomus, one to Acaulospora and one to Scutellospora. No significant relationship existed between AM fungal colonization and spore numbers. Species richness was high in site II and Glomus aggregatum, Glomus viscosum and Glomus mosseae were most frequent species at different sites. Overall species diversity indices (Simpson index, Shannon-Weaver index, species equitability index) differed significantly between sites.     

Arbuscular mycorrhizas in a valley-type savanna in southwest China

The arbuscular mycorrhizal (AM) status of 67 plant species in a savanna community in the hot, dry valley of Jinsha River, southwest China was surveyed. It was found that about 95% of the plant species formed AM and 5% possibly formed AM. The composition of AM fungi (AMF) in the rhizosphere soils was also investigated. The AMF spore density ranged from 5 to 6,400 per 100 g soil, with an average of 1,530, and these spores/sporocarps were identified as belonging to six genera. Fungi belonging to the genera Glomus and Acaulospora were the dominant AMF. High densities of AMF spores in the rhizosphere soils, and the intensive colonization of the plant roots, indicated that plants grown in this valley-type savanna may be highly dependent on AM.     

Arbuscular mycorrhizal status of spring ephemerals in the desert ecosystem of Junggar Basin, China

A survey was made of the arbuscular mycorrhizal (AM) status of 73 spring ephemeral plant species that grow in the desert ecosystem of Junggar Basin, northwest China. The proportion of AM colonization ranged from 7 to 73% with a mean value of 30%. A total of 65 plant species studied were AM with coils/arbuscules or vesicles and the remaining eight species were possibly AM with no coils/arbuscules or vesicles but with fungal mycelia in the root cortex. AM fungal spores were isolated from rhizosphere samples of all 73 plant species and identified. The mean spore density was 22 per 20 ml of air-dried soil, ranging from 0 to 120. Colonization and spore density of perennials were slightly higher than of annuals and varied among different plant families. A total of 603 AM fungal spore (or sporocarp) specimens were isolated belonging to six genera, Acaulospora, Archaeopora, Entrophospora, Glomus, Paraglomus, and Scutellospora; Glomus was the dominant genus. We conclude that spring ephemerals may be highly dependent on AM associations for survival in the very infertile and arid soils of this desert ecosystem.Electronic supplementary material Supplementary material is available for this article at     

Occurrence and distribution of arbuscular mycorrhizal fungal species in three types of grassland community of the Tibetan Plateau

Arbuscular mycorrhizal (AM) fungal spore communities and distribution patterns were surveyed in montane scrub grassland, alpine steppe, and alpine meadow sites at altitudes ranging from 3,500 to 5,200 m a.s.l. on the Tibetan Plateau. Thirty-two representative soil samples were collected from the root zone of the dominant and common plant species in late May 2004. Twenty-three AM fungal species representing six genera (Acaulospora, Entrophospora, Glomus, Pacispora, Paraglomus, and Scutellospora) were detected and species richness varied from 5.3 ± 0.8 to 10.5 ± 2.5 per site. Some AM fungal species were restricted to one vegetation type and Glomus mosseae, Glomus intraradices, and Scutellospora calospora were detected in all three vegetation types. Glomus species were found to be the most frequent and abundant in all three vegetation types. Acaulospora occurred mostly in the alpine steppe and alpine meadow. Scutellospora occurred mostly in montane scrub grassland. At the species level, Glomus mosseae was dominant in the montane scrub, Acaulospora laevis and Pacispora scintillans were dominant in the alpine steppe, and Acaulospora laevis, Pacispora scintillans, and Glomus claroideum dominated the alpine meadow. It was evident from the distribution pattern of AM fungi in the different vegetation types that the abundance and diversity of AM fungal species were lowest in the montane scrub grassland than the other two plant communities. Climatic conditions, especially temperatures, and intensity of land use may be the most important factors influencing the AM fungal community.     

Arbuscular mycorrhizal fungi in non-grazed,restored and over-grazed grassland in the Inner Mongolia steppe

Arbuscular mycorrhizal (AM) fungal diversity was investigated in non-grazed, restored and over-grazed (fenced) plots of a grassland in the Inner Mongolia steppe. Plant cover and variety differ between the plots, being highest in the non-grazed to lowest in the over-grazed plots. A total of 19 AM fungal taxa belonging to six genera were found based on spores isolated from field samples and trap cultures. One belonged to Acaulospora, one to Archaeospora, one to Entrophospora, one to Gigaspora, 12 to Glomus and three to Scutellospora. Glomus was the dominant genus in all plots, and Glomus geosporum was the dominant species, whilst G. albidum and G. etunicatum were dominant in the restored plot. Scutellospora was the second dominant genus in the non-grazed plot with Scutellospora calospora being the dominant species. The mean spore density and mean species richness of AM fungi were significantly decreased by long-term over-grazing. The Sorenson’s similarity coefficients of AM fungal community composition ranged from 0.5 to 0.64 among the three types of plot management. The results suggest that the AM fungal diversity is greatly affected by long-term over-grazing and that fencing of degraded areas partly restores plant cover and AM fungal diversity in grassland ecosystems.     

Mycorrhizal status of <Emphasis Type="Italic">Eucalyptus</Emphasis> plantations in south China and implications for management

The aim of this study is to assess the mycorrhizal status of Eucalyptus plantations in south China and to determine the need for inoculation. In four provinces in south China, 155 plantations were sampled for sporocarps of ectomycorrhizal (ECM) fungi, spores of arbuscular mycorrhizal (AM) fungi, and mycorrhizas over 2 years. This study revealed a low above-ground diversity of ECM fungi consisting of 15 taxa fruiting beneath Eucalyptus plantations. The most common ECM genera were Scleroderma and Pisolithus, but they were infrequent. A total of 21 AM fungi, mostly Glomus species, were recognized from spores collected from eucalypt plantations. Four Glomus species were frequently present in soils, but spore density and relative abundance of AM fungi were generally low. Eucalypt roots from all plantation sites were poorly colonized by either ECM fungi or AM fungi. A bioassay with E. urophylla as a bait host, using soils collected from 11 eucalypt plantations, confirmed low levels of inoculum of both ECM and AM fungi in field soil. This is the first integrated study on the mycorrhizal status of eucalypt plantations in China. Findings from this research can be used to encourage adoption of mycorrhizal technology by eucalypt nurseries in the region. The potential of using spores of compatible ECM fungi or collections for forest nurseries is discussed.     

Arbuscular mycorrhizal fungal community structure and diversity in response to long-term fertilization: a field case from China

The influences of different fertilizer treatments on spore community structure and diversity of arbuscular mycorrhizal (AM) fungi (AMF) were investigated in a long-term fertilization experiment with seven treatments: organic manure (OM), half organic manure N plus half fertilizer N (1/2 OMN), fertilizer NPK, fertilizer NP, fertilizer NK, fertilizer PK, and the control (without fertilization). Fertilization generally increased the nutrient contained in the fertilizer and treatments with NPK and 1/2 OMN produced the highest crop yields. Thirty-five species of AMF within 6 genera, including 8 previously undescribed species, were recovered. Similarly in all seven treatments, the most abundant genus was Glomus, and followed by Acaulospora. All the fertilization treatments changed AM species composition, and NK treatment had the slightest influence. Fertilization with fertilizers NP, PK and NPK markedly increased AM fungal spore density, while 1/2 OMN, OM and NK treatments showed no significant influences. All the fertilizer treatments, especially OM, significantly decreased species richness and species diversity (Shannon-Weiner index). There were no significant correlations between AM fungal parameters (spore density, species richness and species diversity) and soil properties. The findings indicate that long-term fertilization all can change AM fungal community structure and decrease species diversity, while balanced fertilization with NPK or 1/2 OMN is the most suitable fertilization regime if taking both crop yields and AM species diversity into account.     

Vesicular-arbuscular mycorrhizal fungi in coastal dune plant communities I. Spore formation ofGlomus spp. predominates under a patch ofElymus mollis

Vesicular-arbuscular (VA) mycorrhizal fungi in pure patches of coastal dune plantsElymus mollis, Wedelia prostrata andZoysia macrostachya were examined for frequency of occurrence and number of spores of VA mycorrhizal fungi over one year. Six species in three genera of VA mycorrhizal fungi were recovered. Under a patch ofE. mollis, spores ofAcaulospora sp. 1,Glomus tortuosum, Glomus sp. 1,Glomus sp. 2 andScutellospora gregaria were recovered. Spores ofGlomus spp. were most common. In patches ofW. prostrata andZ. macrostachya spores ofAcaulospora sp. 1,G. tortuosum, Glomus sp. 1,Glomus sp. 2,S. gregaria andScutellospora sp. 1 were found.Contribution No. 112, Laboratories of Plant Pathology and Mycology, Institute of Agriculture and Forestry, University of Tsukuba.     

Status of arbuscular mycorrhizal fungi (AMF) in the Sundarbans of India in relation to tidal inundation and chemical properties of soil

The arbuscular mycorrhizal status of fifteen mangroves and one mangrove associate was investigated from 27 sites of three inundation types namely, diurnal, usual springtide and summer springtide. Roots and rhizospheric soil samples were analysed for spore density, frequency of mycorrhizal colonization and some chemical characteristics of soil. Relative abundance, frequency and spore richness of AMF were assessed at each inundation type. All the plant species except Avicennia alba exhibited mycorrhizal colonization. The study demonstrated that mycorrhizal colonization and spore density were more influenced by host plant species than tidal inundation. Forty four AMF species belonging to six genera, namely Acaulospora, Entrophospora, Gigaspora, Glomus, Sclerocystis and Scutellospora, were recorded. Glomus mosseae exhibited highest frequency at all the inundation types; Glomus fistulosum, Sclerocystis coremioides and Glomus mosseae showed highest relative abundance at sites inundated by usual springtides, summer springtides and diurnal tides, respectively. Spore richness of AMF was of the order usual springtide > diurnal > summer springtide inundated sites. The mean spore richness was 3.27. Diurnally inundated sites had the lowest concentrations of salinity, available phosphorus, exchangeable potassium, sodium and magnesium. Statistical analyses indicated that mycorrhizal frequency and AMF spore richness were significantly negatively correlated to soil salinity. Spore richness was also significantly negatively correlated to available phosphorus. The soil parameters of the usual springtide inundated sites appeared to be favourable for the existence of maximum number of AMF. Glomus mosseae was the predominant species in terms of frequency in the soils of the Sundarbans.     

Arbuscular mycorrhizal structure and fungi associated with mosses

We investigated the colonization and diversity of arbuscular mycorrhizal (AM) fungi associated with 24 moss species belonging to 16 families in China. AM fungal structures, i.e. spores, vesicles, hyphal coils (including intracellular hyphae), or intercellular nonseptate hyphae, were found in 21 moss species. AM fungal structures (vesicles, hyphal coils, and intercellular nonseptate hyphae) were present in tissues of 14 moss species, and spores and nonseptate hyphae on the surface of gametophytes occurred in 15 species. AM fungal structures were present in 11 of the 12 saxicolous moss species and in six of the ten terricolous moss species, but absent in two epixylous moss species. AM fungal structures were only observed in moss stem and leaf tissues, but not in rhizoids. A total of 15 AM fungal taxa were isolated based on trap culture with clover, using 13 moss species as inocula. Of these AM fungi, 11 belonged to Glomus, two to Acaulospora, one to Gigaspora, and one to Paraglomus. Our results suggest that AM fungal structures commonly occur in most mosses and that diverse AM fungi, particularly Glomus species, are associated with mosses.     

Dosage-dependent shift in the spore community of arbuscular mycorrhizal fungi following application of tannery sludge

The controlled disposal of tannery sludge in agricultural soils is a viable alternative for recycling such waste; however, the impact of this practice on the arbuscular mycorrhizal fungi (AMF) communities is not well understood. We studied the effects of low-chromium tannery sludge amendment in soils on AMF spore density, species richness and diversity, and root colonization levels. Sludge was applied at four doses to an agricultural field in Rolandia, Paraná state, Brazil. The sludge was left undisturbed on the soil surface and then the area was harrowed and planted with corn. The soil was sampled at four intervals and corn roots once within a year (2007/2008). AMF spore density was low (1 to 49 spores per 50 cm³ of soil) and decreased as doses of tannery sludge increased. AMF root colonization was high (64%) and unaffected by tannery sludge. Eighteen AMF species belonging to six genera (Acaulospora, Glomus, Gigaspora, Scutellospora, Paraglomus, and Ambispora) were recorded. At the sludge doses of 9.0 and 22.6 Mg ha⁻¹, we observed a decrease in AMF species richness and diversity, and changes in their relative frequencies. Hierarchical grouping analysis showed that adding tannery waste to the soil altered AMF spore community in relation to the control, modifying the mycorrhizal status of soil and selectively favoring the sporulation of certain species.     

Diversity and efficiency of arbuscular mycorrhizal fungi in soils from organic chili (Capsicum frutescens) farms

No previous studies have been conducted on the diversity and population of arbuscular mycorrhizal fungi (AMF) in relation to organically grown chili (Capsicum frutescens L.) in Thailand. This study was carried out to investigate the diversity and status of AMF populations at four organically managed farms in Ubon Ratchathani and Sisaket provinces. The effects of each AMF species on the growth and nutrient uptake of chili grown in sterile, organically managed soil were determined. Fourteen AM fungal taxa belonging to the genera Acaulospora (4 spp.), Entrophospora (1 sp.), Glomus (7 spp.) and Scutellospora (2 spp.) were found. Among these, Glomus was the dominant genus found at all sites, followed by Acaulospora. The spore density and root colonization of AMF on chili did not vary significantly among the sites. The effects of ten selected AMF species on the growth of chili showed that Gl. clarum RA0305 increased the growth, flowering, and fruit production of chili, and also increased the P uptake significantly, compared to non-mycorrhizal plants. This fungus showed the highest potential as a promoter of growth, flowering and yield in organically managed chili production.     

蒙古沙冬青及其伴生植物AM真菌物种多样性

于2015年7月在内蒙古乌海、磴口2个样地选取蒙古沙冬青(Ammopiptanthus mongolicus)及其伴生植物为研究对象,分别采集0-20 cm和20-40 cm土层根围土样,利用高通量测序方法分析了不同植物AM真菌群落结构和物种多样性,发掘新物种,为补充和完善AM真菌分类体系提供依据。试验共分离鉴定3纲5目6科9属89个AM真菌OTU,属包括Glomus,Funneliformis,Diversispora,Claroideoglomus,Rhizophagus,Septoglomus,Scutellospora,Ambispora和Paraglomus。与形态学研究结果相比,高通量鉴定结果在属水平上更丰富。同一土层不同样地,蒙古沙冬青AM真菌丰度和多样性指数高于伴生植物;同一土层不同植物,AM真菌丰度和多样性指数表现为磴口高于乌海;同一植物不同样地,AM真菌ACE指数和Chao1指数20-40 cm土层高于0-20 cm土层,Simpson指数和Shannon指数0-20 cm土层高于20-40 cm土层。RDA分析表明,AM真菌ACE指数和Chao1指数与土壤碱解N显著正相关,与酸性磷酸酶显著负相关;Simpson指数和Shannon指数与碱性磷酸酶显著正相关,与pH显著负相关。结果表明,蒙古沙冬青AM真菌物种多样性高于伴生植物,同一样地,寄主植物与土壤深度共同作用对AM真菌群落组成有显著影响。     

Some Mediterranean plant species (Lavandula spp. and Thymus satureioides) act as potential ‘plant nurses’ for the early growth of Cupressus atlantica

The mycorrhizal status of several representative shrub species (Lavandula spp. and Thymus satureioides) in Moroccan semiarid ecosystems, was evaluated as well as their contribution to the mycorrhizal potential of the soil. Furthermore, the rhizosphere soils collected under these target species were tested for their influence on the growth of Cupressus atlantica, a tree species whose natural stands has declined in this area. Soil samples were collected from the rhizosphere of L. stoechas, L. dentata and of C. atlantica existing in the experimental area. Control samples were randomly collected from bare soil sites, away from plant influence.All the target species formed AM symbiosis and the extent of AM fungal colonization was not significantly different between plant species. No significant difference was detected between the total number of AM fungal spores of the bare soil and those recorded in the root zones of target species and C. atlantica. Three genera of AM fungi (Scutellospora, Glomus and Acaulospora) were present in the rhizospheres of the plant species and in the bare soil.The number of mycorrhizal propagules in soil originating from around the four target plant species was significantly higher than the one in the bare soil (Figure 1). The most probable number (MPN) of mycorrhizal propagules per 100 g of dry soil ranged from 7.82 (bare soil) to 179.7 (L. dentata and C. atlantica) and 244.5 (L. stoechas and T. satureioides). As the total number of spores was not different for the soil of different origins, the increase of the mycorrhizal soil infectivity (MSI) mainly resulted from larger AM mycelial networks that constituted the main source of AM fungal inoculum. In addition, this MSI enhancement was linked with changes in the functioning of soil microbial communities. In a glasshouse experiment, the growth of C. atlantica seedlings was significantly higher in the C. atlantica and in the shrub species soils than in the bare soil. Although the AM inoculum potential is not sufficient to ensure the development of forest trees in Mediterranean ecosystems, the use of plant nurses such as T. satureioides or Lavandula spp. could be of great interest to restore a self-sustaining vegetation cover to act against desertification.     

Survey of arbuscular mycorrhizal fungi in deforested and natural forest land in the subtropical region of Dujiangyan, southwest China

The diversity of arbuscular mycorrhizal (AM) fungi in deforested (Mantoushan) and natural forest (Banruosi) land in the subtropical region of Dujiangyan was surveyed and compared. A total of 44 taxa of AM fungi were isolated, and the same number of AM fungus taxa (34 taxa) was found in both deforested and natural forest land. Acaulospora and Glomus were the dominant genera in the two sites. Glomus convolutum and G. versiforme were the dominant species in the natural forest land, while only G. versiforme was dominant in the deforested land. There was no significant difference in total spore density of AM fungi between the two sites, but the total species richness of AM fungi was significantly higher in the deforested land than in the natural forest land. The Shannon-Weiner index of AM fungus diversity was a higher in the natural forest land (2.67) than in the deforested land (2.15). There was high AM fungus composition similarity (Sorenson's coefficient C _S=0.71) between the two sites. We suggest that there was little effect of deforestation on the diversity of AM fungi, and that annual herbaceous plants play a major role in maintaining and increasing AM fungus spore density and species richness in deforested land.