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
gene indicated that these glomerocarps represent two strongly divergent undescribed species in the family Glomeraceae. The analyses placed the first in the genus
, and the second in a sister clade to the monospecific generic clade
with
. The first species was described here as
sp. nov. Because
is the first glomerocarp-forming species in
, the generic description of this genus was emended. The very large phylogenetic distance and the fundamental morphological differences between the second species and
suggested us to introduce a new genus, here named as
gen. nov., and name the new species
sp. nov. In addition, our analyses also focused on an arbuscular mycorrhizal fungus originally described as
, later transferred to the genus
. 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
gen. nov.
Studies of the morphology and the 45S nuc rDNA phylogeny of three potentially undescribed arbuscular mycorrhizal fungi (phylum Glomeromycota) grown in cultures showed that one of these fungi is a new ...species of the genus
in the family Diversisporaceae; the other two fungi are new
species in Scutellosporaceae.
sp. nov. came from maritime sand dunes of the Vistula Spit in northern Poland, and
sp. nov. and
sp. nov. originally inhabited the Mediterranean dunes of the Peloponnese Peninsula, Greece. In addition, the morphological description of spores of
, originally described in 1988, was emended based on newly found specimens, and the so far unknown phylogeny of this species was determined. The phylogenetic analyses of 45S sequences placed this species among
species with atypical phenotypic and histochemical features of components of the two inner germinal walls.
As a result of phylogenomic, phylogenetic, and morphological analyses of members of the genus
, four potential new glomoid spore-producing species and
, a new order, Entrophosporales, with one ...family, Entrophosporaceae (=Claroideoglomeraceae), was erected in the phylum Glomeromycota. The phylogenomic analyses recovered the Entrophosporales as sister to a clade formed by Diversisporales and Glomeraceae. The strongly conserved entrophosporoid morph of
, provided with a newly designated epitype, was shown to represent a group of cryptic species with the potential to produce different glomoid morphs. Of the four potential new species, three enriched the Entrophosporales as new
species,
, and
, which originated from Argentina, Sweden, Oman, and Poland. The fourth fungus appeared to be a glomoid morph of the
epitype. The physical association of the
entrophosporoid and glomoid morphs was reported and illustrated here for the first time. The phylogenetic analyses, using nuc rDNA and
concatenated sequences, confirmed the previous conclusion that the genus
in the family Entrophosporaceae sensu Oehl et al. is an unsupported taxon. Finally, the descriptions of the Glomerales, Entrophosporaceae, and
were emended and new nomenclatural combinations were introduced.
Three new species of arbuscular mycorrhizal fungi of the genus Diversispora (phylum Glomeromycota) were described based on their morphology and molecular phylogeny. The phylogeny was inferred from ...the analyses of the partial 45S rDNA sequences (18S-ITS-28S) and the largest subunit of RNA polymerase II (rpb1) gene. These species were associated in the field with plants colonizing maritime sand dunes of the Baltic Sea in Poland and formed mycorrhiza in single-species cultures.
In the glacier forelands, microbes play a fundamental role in soil development and shaping the vegetation structure. Such ecosystems represent various stages of soil development and are, therefore, ...an excellent place to study the interrelationship between soil, plants, and microorganisms. The aim of the study was to assess the effects of vegetation and soil physicochemical properties developing after glacier retreat on soil microbial communities. Specifically, abundance, species richness and the composition of arbuscular mycorrhizal fungi (AMF), as well as microbial biomass and community structure in soils were compared between plots established in 800-meter transects of three glacier forelands in northern Sweden. The cover of vascular plants and cryptogams, soil C content, AMF spore density and species richness, AMF biomass indicators, total microbial biomass, and bacterial phospholipid fatty acids (PLFA) were significantly and positively related to the distance from the glacier terminus. On the other hand, macronutrient concentrations and pH decreased along with increasing distance. No significant impact of the distance from the glacier terminus on the ratio fungal/bacterial PLFA was observed. Moreover, we found a significant effect of both glacier and the distance from the glacier terminus on the microbial community structure. AMF species richness and spore density in the glacier forelands were generally low, which is probably due to a limited supply of inoculum in primary successional ecosystems. Most microbial biochemical markers and AMF parameters were positively associated with the number of arbuscular mycorrhizal plant species and vascular plant and lichen cover as well as C content in soil, whereas negatively with soil macronutrients and pH. This could be related to an increase in plant cover and a decrease in soil nutrient levels as plant succession progresses. Our results showed that vegetation, soil C content, and microbial communities are interlinked and exhibit concordant patterns along successional gradients.
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•Vegetation, soil and microbial parameters in glacier forelands are interlinked.•Microbial biomass was positively related to the distance from the glacier terminus.•Low soil C and N contents contributed to limited microbial abundance.•Microbial community structure changes with the distance from the glacier terminus.•Distance from the glacier terminus had no impact on the fungal/bacterial PLFA.
The influence of four pre-crop plant species on the occurrence of arbuscular mycorrhizal fungal (AMF, Glomales, Zygomycetes) spores, mycorrhizae and Phialophora graminicola (Deacon) Walker associated ...with roots of field-culuvated XTriticosecale Wittmack cv. Malno was investigated. The pre-crop plant species were Hordeum vulgare L., Lupinus luteus L., Pisum sativum L., and Vicia faba v. major Harz. Most spores and species of AMF were found when XTriticosecale was cultivated following P. sativum. Prior cropping with L. luteus caused the occurrence of the lowest number of spores among XTriticosecale roots. Mycorrhizal colonization of XTriticosecale was highest when planted after P. sativum and lowest when grown after L. luteus.
In the years 1983-1984. the effect of three foliar fungicides, i.e.. Bayleton 25 WP. Dithane M-45 and Funaben K on the mycoflora associated with glumus of spring Tritieum aestivum cv. Kolibri ...cultivated in the field was investigated. During each vegetative period, glumes were collected in the milky ripe of seeds. Fungi species associated with glumes were determined based of colonies isolated from glumes incubated in Petri dishes with potato glucose agar. The fungicide which reduced the most the overall number of fungal isolates was Bayleton 25 WP. The number of species was most reduced following Dithane M-45 application. The mycoflora of glumes which had been untreated and treated with fungicides was compared with fungicides-treated and fungicide-untreated seeds and leaves. The highest similarity in the mycoflora of fungicide-untreated plant parts was found when glumes and seeds were compared. The mycoflora of fungicide-treated glumes, leaves, and seeds varied. depending on the year and fungicide applied.
The author has studied the occurrence and epidemiology of S. nodorum. In addition, attention was paid to the fungus biology, food requirements and other environmental factors (light, temperature) ...necessary to its full development. Effects of fungicides on growth and germination of conidia in vitro were followed as well.
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•The impact of overstorey species on AMF communities was studied.•AMF abundance increased with increasing soil alkalinity and macronutrient levels.•Soils under deciduous tree species ...were characterised by greater AMF abundance.•AMF species composition differed between soils of deciduous and coniferous species.•The differences resulted from several factors acting within groups of tree species.
Despite the presence of arbuscular mycorrhizal fungi (AMF) in temperate forests, knowledge concerning their diversity and interactions with plants is still insufficient. Therefore, we studied the impact of overstorey species identity on AMF abundance and species richness and composition in relation to herbaceous plant cover and soil chemical properties. The effects of 14 tree species grown for 48 years in monospecific plots in the Siemianice Experimental Forest (western Poland) were compared, including the following groupings: deciduous vs coniferous; native to Poland/Europe vs alien; forming vs not forming arbuscular mycorrhizas (AM). Coniferous tree plots were characterised by lower pH values, plots with deciduous trees by higher concentrations of total Ca and exchangeable forms of Ca, K and Mg. AMF abundance in soils and roots increased along with increasing soil alkalinity and macronutrient levels. Concentrations of the PLFA 16:1ω5 AMF hyphal biomass marker were higher in the soils of deciduous and AM-type tree species than those of coniferous and non-AM types. In addition, concentrations of the NLFA 16:1ω5 AMF spore biomass marker were higher in the soils of deciduous tree species. No significant differences were found between groups of native and alien tree species. AMF spore and species numbers were low in comparison to other unforested ecosystems, averaging 77.5 and 1.2 per 50 g of soils, respectively. The presence of 8 AMF species, both widespread (e.g. Funneliformis constrictus) and rare (Acaulospora cavernata) was revealed. Significant divergence in AMF species composition was noted between plots of deciduous and coniferous species. Our study showed that tree species identity, considered as a single factor, has only a slight impact on determining AMF community characteristics. The disparity between AMF community characteristics results from the effects of several factors, as pH and element concentrations in soils, acting within tree species groups.
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