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Morphological analyses of three glomoid spore-producing fungi suggested that two of them were undescribed species of Glomeraceae (phylum Glomeromycota), and the third differed slightly from Dominikia glomerocarpica and Epigeocarpum crypticum, recently described in Glomeraceae. The first two fungi originated from the Mediterranean Sea sand dunes of the Peloponnese, Greece, and the third was originally found in a tree plantation in Yokohama City, Japan. Phylogenetic analyses of sequences of the 45S nuc rDNA region and the RPB1 gene showed that (i) the three fungi belonged to Glomeraceae; (ii) the first two represented a new genus, here described as Complexispora gen. nov. with C. multistratosa sp. nov. and C. mediterranea sp. nov. and (iii) the third enlarged the monospecific genus Epigeocarpum, as E. japonicum sp. nov.

Plant–microbial relations have not yet been fully disclosed in natural or seminatural ecosystems, nor in novel ecosystems developing spontaneously on post-coal mine heaps. The aim of this study was to determine which factor, biotic (plant taxonomic diversity vs. plant functional diversity) or abiotic (physicochemical substrate parameters), affects the biomass of soil microbial communities the most, as well as soil in situ respiration in novel ecosystems. The study was carried out on unreclaimed plots selected according to four different combinations of taxonomic and functional plant diversity. Additionally, plots on a reclaimed heap served as a comparison between the two management types. The biomass of several soil microbial groups was analysed using phospholipid fatty acids profiles. We detected that soil microbial biomass was more impacted by abiotic parameters (explaining 23% of variance) than plant diversity (explaining 12% of variance). Particularly, we observed that substrate pH was the most important factor shaping microbial community biomass, as shown in the RDA analysis. The highest microbial biomass was found in plots with low taxonomic and functional diversity. This finding can be explained by the fact that these plots represented a more advanced phase of vegetation development in the early stages of plant succession.

Changes in soil microbial communities in response to hydrocarbon pollution are critical indicators of disturbed ecosystem conditions. A core component of these communities that is functionally adjusted to the life-history traits of the host and environmental factors consists of arbuscular mycorrhizal fungi (AMF). AMF communities associated with Poa trivialis and Phragmites australis growing at a phenol and polynuclear aromatic hydrocarbon (PAH)-contaminated site and at an uncontaminated site were compared based on LSU rDNA sequencing. Dissimilarities in species composition and community structures indicated soil pollution as the main factor negatively affecting the AMF diversity. The AMF communities at the contaminated site were dominated by fungal generalists (Rhizophagus, Funneliformis, Claroideoglomus, Paraglomus) with wide ecological tolerance. At the control site, the AMF communities were characterized by higher taxonomic and functional diversity than those exposed to the contamination. The host plant identity was the main driver distinguishing the two AMF metacommunities. The AMF communities at the uncontaminated site were represented by Polonospora, Paraglomus, Oehlia, Nanoglomus, Rhizoglomus, Dominikia, and Microdominikia. Polonosporaceae and Paraglomeraceae were particularly dominant in the Ph. australis mycorrhizosphere. The high abundance of early diverging AMF could be due to the use of primers able to detect lineages such as Paraglomeracae that have not been recognized by previously used 18S rDNA primers.

Phylogenetic analyses of sequences of the nuc rDNA small subunit (18S), internal transcribed spacer (ITS1-5.8S-ITS2 = ITS), and large subunit (28S) region (= 18S-ITS-28S), as well as sequences of this region concatenated with sequences of the largest subunit of RNA polymerase II (RPB1) gene, proved that the species originally described as Acaulospora polonica (phylum Glomeromycota) represents a new genus and a new family of the ancient order Archaeosporales, here introduced into the Glomeromycota under the names Polonospora and Polonosporaceae, respectively. The phylogenetic analyses and BLASTn queries also indicated that the Polonosporaceae with P. polonica comb. nov. still contains several morphologically undescribed taxa at the ranks of genus and species, which have a worldwide distribution.

The genus

Dark septate endophytes (DSEs) comprise a diverse and ubiquitous group of fungal generalists with broad habitat niches that robustly colonize the roots of plants in stressful environments. DSEs possess adaptation strategies that determine their high tolerance to heavy metal (HM) contamination, drought, and salinity. Most DSEs developed efficient melanin-dependent and melanin-independent mechanisms of HM detoxification and osmoprotection, including intracellular immobilization and extracellular efflux of HMs and excess ions, and the scavenging of reactive oxygen species. DSEs form mutualistic relationship with plants according to the hypothesis of "habitat-adapted associations", supporting the survival of their hosts under stressful conditions. As saprophytes, DSEs mineralize a complex soil substrate improving plants' nutrition and physiological parameters. They can protect the host plant from HMs by limiting HM accumulation in plant tissues and causing their sequestration in root cell walls as insoluble compounds, preventing further HM translocation to shoots. The presence of DSE in drought-affected plants can substantially ameliorate the physiology and architecture of root systems, improving their hydraulic properties. Plant growth-promoting features, supported by the versatility and easy culturing of DSEs, determine their high potential to enhance phytoremediation and revegetation projects for HM-contaminated, saline, and desertic lands reclamation.

Two glomoid spore-producing arbuscular mycorrhizal fungi were grown in single-species cultures established from soil-borne spores collected from high altitude (2,800 m a.s.l.) of Tibet Plateau, China. Phylogenetic analyses were performed with sequences of nuclear rDNA (spanning the partial small subunit, whole internal transcribed spacer, and partial large subunit segment = 18S-ITS-28S) and the largest subunit of RNA polymerase II (RPB1) gene. Morphological and phylogenetic analyses indicated that the two fungi are undescribed species of the genera Glomus and Dominikia. The first fungus, described here as G. chinense sp. nov., formed spores singly and in loose clusters. The spores are orange-yellow to dark brown, globose, (47–)64(–93) µm diam. Dominikia gansuensis sp. nov. produced glomerocarps with pale yellow to yellow-brown, globose, (20–)47(–86) µm diam spores. Spore wall of both species consists of three layers. Both species differ clearly in morphology and phylogeny from their closest phylogenetic relatives, which are G. atlanticum and G. ibericum, and D. glomerocarpica, respectively.

We examined three arbuscular mycorrhizal fungi (AMF; phylum Glomeromycota) producing glomoid spores. The mode of formation and morphology of these spores suggested that they represent undescribed species in the genus Rhizoglomus of the family Glomeraceae. Subsequent morphological studies of the spores and molecular phylogenetic analyses of sequences of the nuc rDNA small subunit (18S), internal transcribed spacer (ITS1-5.8S-ITS2 = ITS), and large subunit (28S) region (= 18S-ITS-28S) confirmed the suggestion and indicated that the fungi strongly differ from all previously described Rhizoglomus species with known DNA barcodes. Consequently, the fungi were described here as new species: R. dalpeae, R. maiae, and R. silesianum. Two of these species lived hypogeously in the field in habitats subjected to strong environmental stresses. Rhizoglomus dalpeae originated from an inselberg located within Guineo-Sudanian transition savanna zone in Benin, West Africa, where the temperature of the inselberg rock during a 5-mo drought ranges from 40 to 60 C. Rhizoglomus silesianum originated from a coal mine spoil heap in Poland, whose substrate is extremely poor in nutrients, has unfavorable texture, and may heat up to 50 C. By contrast, R. maiae was found in more favorable habitat conditions. It produced an epigeous cluster of spores among shrubs growing in a tropical humid reserve in Brazil. Moreover, the compatibility of phylogenies of species of the family Glomeraceae reconstructed from analyses of sequences of 18S-ITS-28S and the largest subunit of RNA polymerase II (RPB1) gene was discussed.

Arbuscular mycorrhizal fungi (AMF) are ubiquitous mutualistic plant symbionts that promote plant growth and protect them from abiotic stresses. Studies on AMF-assisted phytoremediation have shown that AMF can increase plant tolerance to the presence of hydrocarbon contaminants by improving plant nutrition status and mitigating oxidative stress. This work aimed to evaluate the impact of single and mixed-species AMF inocula (Funneliformis caledonium, Diversispora varaderana, Claroideoglomus walkeri), obtained from a contaminated environment, on the growth, oxidative stress (DNA oxidation and lipid peroxidation), and activity of antioxidative enzymes (superoxide dismutase, catalase, peroxidase) in Lolium perenne growing on a substrate contaminated with 0/0–30/120 mg phenol/polynuclear aromatic hydrocarbons (PAHs) kg−1. The assessment of AMF tolerance to the presence of contaminants was based on mycorrhizal root colonization, spore production, the level of oxidative stress, and antioxidative activity in AMF spores. In contrast to the mixed-species AMF inoculum, single AMF species significantly enhanced the growth of host plants cultured on the contaminated substrate. The effect of inoculation on the level of oxidative stress and the activity of antioxidative enzymes in plant tissues differed between the AMF species. Changes in the level of oxidative stress and the activity of antioxidative enzymes in AMF spores in response to contamination also depended on AMF species. Although the concentration of phenol and PAHs had a negative effect on the production of AMF spores, low (5/20 mg phenol/PAHs kg−1) and medium (15/60 mg phenol/PAHs kg−1) substrate contamination stimulated the mycorrhizal colonization of roots. Among the studied AMF species, F. caledonium was the most tolerant to phenol and PAHs and showed the highest potential in plant growth promotion. The results presented in this study might contribute to the development of functionally customized AMF-assisted phytoremediation strategies with indigenous AMF, more effective than commercial AMF inocula, as a result of their selection by the presence of contaminants.

Climate change has become a fact, and its effects are felt by people around the globe. Particularly dangerous are prolonged droughts, since they not only have a negative effect on the development of plants, but also become the cause of many dangerous diseases. The intensive use of fertilizers and pesticides or melioration as a support for agricultural production turned out to be highly harmful to the soil, and in many places led to its degradation. Much of the world is struggling with a lack of proper hydration, and desertification is beginning to threaten all continents. The research results of interdisciplinary scientific teams focused on counteracting environmental devastation and restoring vital biodiversity are not only diligently followed, but also applied as quickly as possible.

Examination of fungal specimens collected in the Atlantic rain forest ecosystems of Northeast Brazil revealed many potentially new epigeous and semihypogeous glomerocarp-producing species of the phylum Glomeromycota. Among them were two fungi that formed unorganized epigeous glomerocarps with glomoid spores of almost identical morphology. The sole structure that distinguished the two fungi was the laminate layer 2 of their three-layered spore wall, which in spores of the second fungus crushed in PVLG-based mountants contracted and, consequently, transferred into a crown-like structure. Surprisingly, phylogenetic analyses of sequences of the 18S-ITS-28S nuc rDNA and the rpb1 gene indicated that these glomerocarps represent two strongly divergent undescribed species in the family Glomeraceae. The analyses placed the first in the genus Dominikia, and the second in a sister clade to the monospecific generic clade Kamienskia with Kamienskia bistrata. The first species was described here as Dominikia glomerocarpica sp. nov. Because D. glomerocarpica is the first glomerocarp-forming species in Dominikia, the generic description of this genus was emended. The very large phylogenetic distance and the fundamental morphological differences between the second species and K. bistrata suggested us to introduce a new genus, here named as Epigeocarpum gen. nov., and name the new species Epigeocarpum crypticum sp. nov. In addition, our analyses also focused on an arbuscular mycorrhizal fungus originally described as Rhizophagus neocaledonicus, later transferred to the genus Rhizoglomus. The analyses indicated that this species does not belong to any of these two genera but represents a new clade at the rank of genus in the Glomeraceae, here described as Silvaspora gen. nov.

Examination of morphological characters of two arbuscular mycorrhizal fungi (AMF; phylum Glomeromycota), which produced clusters with glomoid spores in single-species cultures, suggested that they were undescribed species, one belonging to the genera Dominikia, Microdominikia or Kamienskia, and one to the genus Glomus. Phylogenetic analyses of the nuc rDNA small subunit (18S), internal transcribed spacer (ITS1-5.8S-ITS2 = ITS) and large subunit (28S) (= 18S-ITS-28S) region, of the largest subunit of RNA polymerase II (RPB1) gene, as well as of concatenated sequences of these two loci (18S-ITS-28S + RPB1) confirmed our hypotheses and proved that both fungi were new species, here described as Dominikia bonfanteae sp. nov. and Glomus atlanticum sp. nov., respectively. In nature, D. bonfanteae was found in a plant community on the shore of Kokotek pond II (Lubliniec in the Silesian Upland, Poland). Glomus atlanticum originated from the Dunes of Aguda Park (Northern Portugal). The phylogenetic position of these new species and their close family relatives within the Glomeraceae were compared and discussed depending on the sequence alignment analysed. This paper for the first time shows the phylogeny of AMF reconstructed from analyses of two concatenated unlinked loci: 18S-ITS-28S plus RPB1. The partial RPB1 gene of D. bonfanteae was amplified using newly designed primers.

Examination of fungal specimens collected in the Atlantic rain forest ecosystems of Northeast Brazil revealed many potentially new epigeous and semihypogeous glomerocarp-producing species of the phylum Glomeromycota. Among them were two fungi that formed unorganized epigeous glomerocarps with glomoid spores of almost identical morphology. The sole structure that distinguished the two fungi was the laminate layer 2 of their three-layered spore wall, which in spores of the second fungus crushed in PVLG-based mountants contracted and, consequently, transferred into a crown-like structure. Surprisingly, phylogenetic analyses of sequences of the 18S-ITS-28S nuc rDNA and the rpb1 gene indicated that these glomerocarps represent two strongly divergent undescribed species in the family Glomeraceae. The analyses placed the first in the genus Dominikia, and the second in a sister clade to the monospecific generic clade Kamienskia with Kamienskia bistrata. The first species was described here as Dominikia glomerocarpica sp. nov. Because D. glomerocarpica is the first glomerocarp-forming species in Dominikia, the generic description of this genus was emended. The very large phylogenetic distance and the fundamental morphological differences between the second species and K. bistrata suggested us to introduce a new genus, here named as Epigeocarpum gen. nov., and name the new species Epigeocarpum crypticum sp. nov. In addition, our analyses also focused on an arbuscular mycorrhizal fungus originally described as Rhizophagus neocaledonicus, later transferred to the genus Rhizoglomus. The analyses indicated that this species does not belong to any of these two genera but represents a new clade at the rank of genus in the Glomeraceae, here described as Silvaspora gen. nov.

The natural mineral resources (hard coal, sands, dolomites, lead and zinc ores) found in the Silesia and the excavation of them led to significant transformation or even degradation of the environment. The landscape of Upper Silesia was dominated by heaps created as a result of the accumulation of post-mining coal waste. These post-industrial sites are characterised by difficult conditions for the development of plant communities. Nevertheless, the heaps are spontaneously overgrowing and over time, a separate ecosystem can be observed (for heaps). The article analyzes the enzymatic activity of the substrate in relation to the selected dominant grass (Monocots) and herbaceous (Dicots) plant species. The aim of this study was to compare the activity of particular enzymes in soil substratum of the vegetation patches dominated by grass and herbaceous plants.

Dominant species influence both species and functional composition of the vegetation as well as soil properties of the substrate. However, knowledge about the role played by dominant species in the process of shaping their habitat within post-industrial ecosystems is still limited. We aimed to assess the impact of four dominant species (Calamagrostis epigejos, Daucus carota, Poa compressa and Tussilago farfara) on soil abiotic and biotic properties, and to detect differences in species and functional composition of the vegetation types studied. We hypothesized that (1) dominant species of higher mean biomass cause lower aboveground biodiversity and (2) dominant species of higher mean biomass have a higher impact than the others on soil properties. We measured soil chemistry (TOC, N, P, K, Na, Mg content, EC, pH and enzyme activities) as well as biomass, species diversity and functional diversity of vegetation on 15 study plots (28.3 m2) for each species studied. The DCA analysis revealed a clear distinction between the patches dominated by studied species. Vegetation patches dominated by Calamagrostis epigejos were correlated with amount of biomass, canopy height CWM and specific leaf CWM. Patches dominated by Daucus carota were related to the light requirements (EIV-L), Total Organic Carbon (TOC) and K content. The vegetation patches dominated by Poa compressa were related to dehydrogenase activity, higher Mg content and species richness of the vegetation patches. The highest TOC content was recorded for T. farfara substrates, and the lowest for C. epigejos substrates. The content of potassium does not differ statistically significantly in the substrates from sites dominated by D. carota and P. compressa. The highest values of Mg content were recorded for D. carota and were statistically different from Poa compressa sites, while the higher phosphorus content (statistically significantly different) was recorded for patches dominated by T. farfara and P. compressa. Despite our assumptions, the species with the highest mean biomass (Calamagrostis epigejos) did not cause lower species or functional diversity. In contrast, Tussilago farfara has the highest impact on postindustrial site habitats on coal mine heaps, as extreme values of four soil substratum parameters were recorded on these plots. This species also decreased both species and functional diversity of vegetation. The knowledge about relationship existing between plants (aboveground vegetation) and soil organisms seems important in order to undertake suitable reclamation measures and to restore variety of functions as well as to create diverse vegetation based on native species.

The relationship between the size of the particle fractions of the soil substrate and the diversity of the spontaneously developing vegetation was investigated on coal mine spoil heaps in Upper Silesia (Southern Poland). The analyses were based on 2567 research plots of developed spontaneous vegetation and their associated soil substrate samples collected from 112 coal mine spoil heaps. For each research plot the prevailing particle size fraction was determined (stones, gravel, sand, silt), the species composition and abundance was recorded and the species richness (S), Shannon-Wiener diversity index (H′), Simpson (C) and Evenness (E) indices were used to determine species diversity. From a total of 119 research plots (in all particle size fraction categories), the values of 15 physicochemical properties (pH, electrical conductivity, water holding capacity, moisture, carbon content, total N, available P, Mg and exchange cations Ca, Mg, K, Na, fine particles (%), gravel (%), stone (%)) were obtained to asses their impact on the floristic composition of vegetation patches using Canonical Correspondence Analysis (CCA). Additionally, functional traits of the dominant species of each vegetation patch (life forms, life strategies and socio-ecological groups), were selected to analyse their relation to substrate texture. It was shown that the highest species richness and the highest values for Shannon-Wiener diversity index, as well as Simpson and Evenness indices, were obtained in plots formed on stones. Moreover, the greatest variation in the participation of species representing different habitats, life forms, and life strategies was found on gravelly substrates. Contrary to our expectations, the vegetation diversity (in terms of both species and their functional traits) was not highest in habitats with a high composition of fine size particles.

Among the ecological services provided by arbuscular mycorrhizal fungi (AMF), the process of soil aggregation is hypothesized to be partially mediated by glomalin, an alkaline-soluble glycoprotein released by AM fungi into soil during hyphal turnover and after the death of the fungus in the soil. The protein is characterized by abundant production and hydrophobic properties. Although glomalin has been identified in Rhizophagus irregularis DAOM 197198 as a putative homolog of heat shock protein 60, the use of expressed fungal genes encoding glomalin as a marker for functional AMF diversity was never exploited. The present work describes the first attempt to identify the glomalin gene in several AMF species, verify its reliability as gene marker for the identification and discrimination of AMF, and test the possibility to detect its expression in soil. We designed a specific PCR primers set able to amplify many known lineages of AMF glomalin gene. We demonstrated its applicability to create a new reference glomalin sequence dataset for comparative sequence analysis. The designed primer set was successfully used to amplify glomalin transcript from soil cDNA template.

Grasses have a considerable potential for the adaptation to various, often extreme, habitat conditions. The aim of the work was to present the vegetation diversity of the coal-mine spoil heaps with the dominant share of grasses and to identify the main factors responsible for this diversity in the aspect of post-industrial land reclamation. The communities differ in reference to the species preferences to light, moisture, soil fertility and reaction, which is reflected in the wide variety of microhabitats in the area. It was shown that the increase in the abundance of certain grass species, including Calamagrostis epigejos, Festuca rubra, Festuca arundinacea, Phragmites australis, has a significant negative impact on the species richness, species diversity and the uniformity of distribution of species of the plant community. Preliminary analyses revealed that on post-mining waste, the biomass production of the dominant species is negatively correlated with biodiversity. The knowledge about the biology and ecology of grass species, as well as on the assembly rules may be used in the reclamation of degraded areas. Gaining the knowledge about the vegetation diversity of the coal-mine spoil heaps with the dominant share of grasses can be useful in planning the reclamation works, taking into account natural processes, which leads to the creation of a permanent vegetation cover at a given site, protecting it against water or wind erosion. In the future these areas may provide a number of important ecosystem services.

Arbuscular mycorrhizal fungi (AMF) are ubiquitous, obligatory plant symbionts that have a beneficial influence on plants in contaminated environments. This study focused on evaluating the biomass and biodiversity of the AMF and microbial communities associated with Poa trivialis and Phragmites australis plants sampled at an aged site contaminated with phenol and polynuclear aromatic hydrocarbons (PAHs) and an uncontaminated control site. We analyzed the soil phospholipid fatty acid profile to describe the general structure of microbial communities. PCR-denaturing gradient gel electrophoresis with primers targeting the 18S ribosomal RNA gene was used to characterize the biodiversity of the AMF communities and identify dominant AMF species associated with the host plants in the polluted and control environments. The root mycorrhizal colonization and AMF biomass in the soil were negatively affected by the presence of PAHs and phenol, with no significant differences between the studied plant species, whereas the biodiversity of the AMF communities were influenced by the soil contamination and plant species. Soil contamination was more detrimental to the biodiversity of AMF communities associated with Ph. australis, compared to P. trivialis. Both species favored the development of different AMF species, which might be related to the specific features of their different root systems and soil microbial communities. The contaminated site was dominated by AMF generalists like Funneliformis and Rhizophagus, whereas in the control site Dominikia, Archaeospora, Claroideoglomus, Glomus, and Diversispora were also detected.

Consumption of chili peppers (Capsicum frutescens L.) represents an important aspect of the daily diet for Vietnamese population because of its high content for antioxidant compounds. To increase the economic benefits related to chili peppers cultivation and reduce negative impacts of the high input agriculture on the environment, biological alternatives to chemical fertilizers are strongly demanded. Arbuscular mycorrhizal fungi (AMF) are well-known soil microorganisms of great interest for their potential application in agriculture as ‘bio- enhancers’ of plant performance. However selection of suitable AMF strains is time-costing and the outcome of field inoculation can be affected by the weak ability to compete among the native AMF population. In the present study we proposed a “bulk” approach to identify soil hosting AMF strains suitable for the development of inocula for C. frutescens. Three different soils were tested as source of AMF inoculum in bi-compartmented pot cultures. All the inoculated treatments performed significantly better, in terms of plant growth, compared with the non- inoculated control plants. Pots inoculated with soil from tropical forest showed the best growth performances. Molecular characterization of the AMF root assemblages highlighted differences in the composition among treatments, with the “tropical forest soil” treatment characterized by the highest number of AMF taxa colonizing the roots.

Depending on commodity and region, postharvest diseases can cause considerable economic losses. Although effective against postharvest pathogens, synthetic pesticides have gained increasingly negative attention over the past years from the public opinion. Among natural fungicides, plant derived compounds such as essential oils (EOs), have become topic of increasing discussion over the last couple of decades as safe and ecologically friendly alternatives to synthetic pesticides. Grey mould caused by Botrytis cinerea is an important postharvest disease of strawberries and many other horticultural products. In the present study the antifungal potential of Thymus vulgaris essential oil was tested on individual strawberries artificially inoculated with Botrytis cinerea. Two dilutions of thyme essential oil, 200 μl/ml and 500 μl/ml, were applied to strawberry fruits and incubated for a period of 13 days. The dilution 500 μl/ml effectively suppressed fungal growth in strawberries for a period of 7 days, more than twice as long as the control group. Furthermore only one out of five replications in the 500 μl/ml treatment was visibly infected while the others remained free from infection for the entirety of the experiment. At experiment conclusion the strawberries in the 500 μl/ml treatment maintained a healthier shape, firmness, and colour compared to the control and 200 μl/ml treatment. This study has confirmed that the application of thyme essential oil could be an efficient biocontrol tool in postharvest stage.

In the last decades the management of arbuscular mycorrhizal fungi (AMF) has drawn increasing attention as a biological alternative to chemicals. For a profitable capitalization of these symbiota, a better understanding of which mechanisms could affect the dynamics of AMF communities is required. In the present study we evaluated the influence of different crop rotations on the AMF communities, after a 50 years field experiment established at Martonvasar, Hungary. Four types of crop rotation were chosen for sampling: corn monocropping as a control, corn-alfalfa, corn-wheat and corn-spring barley-peas-wheat. The level of root mycorrhization and the spore abundance in the soil were measured at different sampling times. Community composition of AMF in roots was analyzed with a molecular approach amplifying a portion of 18S rDNA. In the corn monoculture we found a relatively rich AMF community, with a number of phylotypes detected (11) higher than those found in previous works by molecular tools. Comparing the different crop rotation types highlighted remarkable differences in the composition and structure of the AMF assemblages showing that the nature of crop sequence has, in the long term, an important role in modeling the resident AMF community.

The rising claim for more environmental friendly and healthy agriculture is a strong incentive to find alternative strategies to replace the use of mineral fertilizer and pesticide. Arbuscular mycorrhizal fungi (AMF), a main component of soil microbiota, represent a promising tool as providers of key ecological services. The present work represented one of the first attempts to study, under a morphological and molecular point of view, the AMF communities associated to some strategic crops in Vietnam. The findings about the AMF morphotypes dominant in different crop systems could be a starting point for the development of well performing and adapted inocula suitable for the application in field.

Summary In field conditions, grapevine roots normally are colo- nized by arbuscular mycorrhizal fungi (AMF). However, little is published, from either morphologi- cal or molecular studies, on the species composition of these symbionts in production vineyards. The AMF biodiversity of two Piedmont vineyards (at Neive and Lessona), characterized by different soil features, was investigated by morphological and molecular analyses. Several morphotypes were identified from the two vineyard soils. Community composition of AMF, both in soil and root samples, was then analy- sed with molecular approach to amplify a portion (550 bp) of AM fungal SSU rDNA. Phylogenetic analy- ses show a different distribution of sequences from the two sites in the main glomeromycotan groups. In the Neive site, the Glomeraceae group A is the only one well represented whereas more groups were found at Lessona. Among the more representative operational taxonomic units (OTUs), only one related to the Glomus irregulare phylotype was shared between the two vineyard soils. The data obtained in this work together with similar results in literature on this important fruit crop reinforce the concept that the general AMF assemblage structure and composition in vineyards might be influenced more by soil type than by host plant features (age, vegetative stages) or management practices.

SummaryAnemone coronaria is an out-crossing species grown widely as an ornamental. The genetic divergence between and within five widely commercialised cultivars (‘Cristrina’, ‘Monalisa’, ‘Tetraelite’, ‘Wicabri’ and ‘Mistral’) has been evaluated using AFLP markers. Within each cultivar three-to-eight sub-cultivars, which differ mainly in the colour of their flowers, were assayed. Four plants within each sub-cultivar were genotyped. Due to the large size of the A. coronaria genome, an AFLP protocol based on restriction with Sbf I (an 8 bp cutter) and Mse I (a 4 bp cutter) was developed. Clear and reproducible electrophoretic patterns displaying 56 – 79 bands (average 67) per primer combination were obtained by applying five (Sbf I+2 / Mse I+3) selective nucleotides. A total of 402 bands were observed, of which 152 were polymorphic. Genetic similarities between accessions were calculated according to the Simple Matching Coefficient and used to construct a dendrogram based on the unweighted pair group method...

We report on the development of 11 (from database expressed sequence tags) dbEST-derived microsatellite markers in celery (Apium graveolens L. var. dulce). The sequences were obtained from DNA accessions available from GenBank and contained di-, tri- and pentanucleotidic motifs. All the microsatellites were found in expressed sequence tags and they are expected to become useful tools for ecological, genetic and evolutionary studies, as well as for celery breeding. Polymorphism was explored in 16 celery commercial varieties, and marker transferability was tested on three accessions of celeriac (A. graveolens var. rapaceum). Primers and PCR conditions for microsatellite amplification are reported.

Given the attention drawn since several decades by arbuscular mycorrhizal fungi (AMF) as potential biological alternatives to chemicals in a low-input agriculture, much effort has been spent in the investigation of mechanisms influencing the dynamics inside AMF communities. In the present study we evaluated the influence of different crop rotations on the AMF soil community, after a 50 y long-term field experiment established at Martonvasar, Hungary. Four types of crop rotation were chosen for sampling: corn monocropping, corn-alfalfa, corn-wheat, and corn-spring barley-peas-wheat. Community composition of AMF in soil was analyzed with a molecular approach amplifying a portion of 28S rDNA. The crop rotation practice didn’t show an influence on identity of the species composing AMF assemblages, but on the other hand seemed to affect positively the true diversity, defined as number of MOTUs present in the communities.

In field conditions, grapevine roots normally are colonized by arbuscular mycorrhizal fungi (AMF). However, little is published, from either morphological or molecular studies, on the species composition of these symbionts in production vineyards. The AMF biodiversity of two Piedmont vineyards (at Neive and Lessona), characterized by different soil features, was investigated by morphological and molecular analyses. Several morphotypes were identified from the two vineyard soils. Community composition of AMF, both in soil and root samples, was then analysed with molecular approach to amplify a portion (550 bp) of AM fungal SSU rDNA. Phylogenetic analyses show a different distribution of sequences from the two sites in the main glomeromycotan groups. In the Neive site, the Glomeraceae group A is the only one well represented whereas more groups were found at Lessona. Among the more representative operational taxonomic units (OTUs), only one related to the Glomus irregulare phylotype was shared between the two vineyard soils. The data obtained in this work together with similar results in literature on this important fruit crop reinforce the concept that the general AMF assemblage structure and composition in vineyards might be influenced more by soil type than by host plant features (age, vegetative stages) or management practices.

A number of horticultural crop landraces are still grown in Piedmont (NW Italy), despite the dominance of improved cultivars and hybrids. Conservation strategies, both in an ex situ and an in situ context are required to prevent their loss. Here we describe an AFLP-based assessment of the genetic structure of leek, garlic, celery, red beet, cultivated cardoon, sweet pepper and common bean autochthonous landraces. Each landrace was sampled by selecting 3–5 populations representative of the area of cultivation. The genotypic data showed that the crop's breeding system was less important for determining genetic structure than the selection criteria adopted by the producers, the extent of informal seed exchange among producers and natural selection imposed by the local environmental conditions. The genotypic data identified alleles which were common, some which were restricted to a particular locality and some which were either infrequent or rare. On this basis, the most representative population(s) for each landrace were recognised and targeted for conservation. The landraces in study differed markedly from one another with respect to their genetic structure, and so they may represent an appropriate reference model for the management of crop landraces grown in fragmented areas and at risk of genetic erosion or extinction.

A high copy number of retrotransposon sequences are present and widely dispersed in plant genomes. Their activity generates a considerable degree of sequence polymorphism. Here, we report the cloning of CYRE-5, a long-terminal repeat carrying retrotransposon-like sequence in Cynara cardunculus L., and its exploitation to develop a DNA fingerprinting assay across 22 accessions, including both cultivated (globe artichoke and cultivated cardoon) and wild (wild cardoon) types. The effectiveness of the sequence-specific amplified polymorphism (S-SAP) platform is compared with that of amplified fragment length polymorphism (AFLP). A genetic linkage analysis, based on a hybrid population between 2 globe artichoke varietal types, resulted in the inclusion of 29 S-SAP loci in the core genetic map, confirming their dispersed distribution across the globe artichoke genome.