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Blood flukes of freshwater fish are understudied worldwide. Consequently, genetic information and data on their intramolluscan stages are scarce. In the current study, freshwater limpets of the genus Burnupia (Burnupiidae) from South Africa were examined for digeneans. Of 1645 specimens, 3.10% were infected by Sanguinicolidae larvae. Four sanguinicolids were distinguished by body size, number of penetration glands, tegumental spines’ patterns and relative sizes of the finfolds on the body and furcae. Analyses of 28S, 18S and ITS rDNA sequences showed that the morphotypes were distinct from each other and from sanguinicolids whose genetic data are available. The present study is the first genetic characterization of sanguinicolids from Africa. Phylogenetic reconstruction revealed that the present species clustered with a sanguinicolid from Poland and were sister to Sanguinicola and Pseudosanguinicola from Russia and USA, respectively. The results indicate that the current species represent an unknown genus. What is more, blood fluke sequences from East Africa (presumed to be sanguinicolids), were distant from Sanguinicolidae and showed a closer relationship with acipensericolids from the USA. Freshwater fish blood flukes seem to be more diverse than previously recorded and use species of at least 13 gastropod families as intermediate hosts.

The continental coasts and remote islands in the high‐latitude Southern Hemisphere, including the subantarctic region, are characterized by many endemic species, high abundance of taxa, and intermediate levels of biodiversity. The macroalgal flora of these locations has received relatively little attention. Filamentous green algae are prolific in the intertidal of southern islands, but the taxonomy, distribution, and evolutionary history of these taxa are yet to be fully explored, mostly due to the difficulty of access to some of these locations. In this study, we examined specimens of the order Cladophorales from various locations in the high‐latitude Southern Hemisphere including the subantarctic (the Auckland Islands, Bounty Islands, Campbell Island, Macquarie Island, and Kerguelen Islands), as well as mainland New Zealand, the Chatham Islands, Chile, and Tasmania. The analyses of the rDNA sequences of the samples revealed the existence of two new clades in a phylogeny of the Cladophoraceae. One of these clades is described as the novel genus Vandenhoekia gen. nov., which contains three species that are branched or unbranched. The amended genus Rama is reinstated to accommodate the other clade, and contains four species, including the Northern Hemisphere "Cladophora rupestris." In Rama both branched and unbranched morphologies are found. It is remarkable that gross morphology is not a predictor for generic affiliations in these algae. This study illustrates that much can still be learned about diversity in the Cladophorales and highlights the importance of new collections, especially in novel locations. [ABSTRACT FROM AUTHOR]

During an investigation on freshwater peritrichs, a new colonial sessilid ciliate, Campanella sinica n. sp., was isolated from aquatic plants in an artificial freshwater pond in Qingdao, China. Specimen observations of this species were performed both in vivo and using silver staining. C. sinica n. sp. is characterized by the appearance of the mature colony, which is up to 2 cm high and contains more than 1,000 zooids, the asymmetric horn-shaped zooids, strongly everted and multi-layered peristomial lip, the slightly convex peristomial disc, and the well-developed haplokinety and polykinety, which make more than four circuits of the peristome before descending into the infundibulum. The small subunit ribosomal DNA (SSU rDNA), 5.8s rDNA and its flank internal transcribed spacers (ITS1-5.8s rDNA-ITS2), and large subunit ribosomal DNA (LSU rDNA) are sequenced and used for phylogenetic analyses which reveal that the family Epistylididae Kahl, 1933 is non-monophyletic whereas the genus Campanella is monophyletic and nests within the basal clade of the sessilids. The integrative results support the assertion that the genus Campanella represents a separate lineage from other epistylidids, suggesting a further revision of the family Epistylididae is needed. We revise Campanella including the transfer into this genus of a taxon formerly assigned to Epistylis, which we raise to species rank, i.e., Campanella ovata (Nenninger, 1948) n. grad. & n. comb. (original combination Epistylis purneri f. ovataNenninger, 1948). In addition, we provide a key to the identification of the species of Campanella.

During an investigation on freshwater peritrichs, a new colonial sessilid ciliate, Campanella sinica n. sp., was isolated from aquatic plants in an artificial freshwater pond in Qingdao, China. Specimen observations of this species were performed both in vivo and using silver staining. C. sinica n. sp. is characterized by the appearance of the mature colony, which is up to 2 cm high and contains more than 1,000 zooids, the asymmetric horn-shaped zooids, strongly everted and multi-layered peristomial lip, the slightly convex peristomial disc, and the well-developed haplokinety and polykinety, which make more than four circuits of the peristome before descending into the infundibulum. The small subunit ribosomal DNA (SSU rDNA), 5.8s rDNA and its flank internal transcribed spacers (ITS1-5.8s rDNA-ITS2), and large subunit ribosomal DNA (LSU rDNA) are sequenced and used for phylogenetic analyses which reveal that the family Epistylididae Kahl, 1933 is non-monophyletic whereas the genus Campanella is monophyletic and nests within the basal clade of the sessilids. The integrative results support the assertion that the genus Campanella represents a separate lineage from other epistylidids, suggesting a further revision of the family Epistylididae is needed. We revise Campanella including the transfer into this genus of a taxon formerly assigned to Epistylis , which we raise to species rank, i.e., Campanella ovata (Nenninger, 1948) n. grad. & n. comb. (original combination Epistylis purneri f. ovata Nenninger, 1948). In addition, we provide a key to the identification of the species of Campanella. [ABSTRACT FROM AUTHOR]

Ektaphelenchoides pini, the type species of the genus Ektaphe­lenchoides, was recovered from wood and bark samples of a dead broadleaf forest tree collected from the forests of Golestan province in north of Iran. The recovered population is mainly characterized by massive wide spicules of males with well-developed condylus marked by indentations at the apex and simple distal tip. It was further characterized by 756 to 947 μ m long females having a cephalic region slightly separated from the rest body by a shallow depression, 20 to 23 μ m stylet with wide lumen lacking conophore and knobs, excretory pore (E pore) at about one metacorpus length behind it, or 92 to 106 μ m from anterior end and hemizonid just posterior to it, vagina anteriorly inclined, post uterine sac (PUS) ca 1.2 times vulval body width long, posterior body region elongate conoid, ending to a filiform tip, no functional rectum, a vestigial anus and common males with dorsally convex tail ending to an elongate spike and two pairs of precloacal (P2) and caudal (P3) large papillae at 5 to 6 μ m distance anterior to cloacal opening and 30 to 41% of tail, respectively and lacking the single precloacal papilla (P1). In molecular phylogenetic analyses using small and large subunit ribosomal DNA (SSU, LSU rDNA) sequences, the Iranian population of E. pini fell in a clade including species of three genera Ektaphelenchus, Ektaphelenchoides, and Devibursaphelenchus in SSU, and a clade including species of Ektaphelenchus and Ektaphelenchoides in LSU tree, in close association with an isolate identified as E. pini in the latter phylogeny with high (0.99) Bayesian posterior probability (BPP). The comparisons with the type and French populations, as well as phylogenetic affinities of the species using ribosomal data, are discussed. This is the first report of E. pini from Iran, and its first simultaneous morphological and molecular phylogenetic study. New observations on some species of the genus were also presented and discussed. [ABSTRACT FROM AUTHOR]

The 35S and 5S ribosomal DNA (rDNA) organized in thousands of copies in genomes, have been widely used in numerous comparative cytogenetic studies. Nevertheless, several questions related to the diversity and organization of regulatory motifs in 5S rDNA remain to be addressed. The 5S rDNA unit is composed of a conserved 120 bp length coding region and an intergenic spacer (IGS) containing potential regulatory motifs (Poly-T, AT-rich and GC-rich) differing in number, redundancy and position along the IGS. The Cestrum species (Solanaceae) have large genomes (about 10 pg/1C) and conserved 2n = 16 karyotypes. Strikingly, these genomes show high diversity of heterochromatin distribution, variability in 35S rDNA loci and the occurrence of B chromosomes. However, the 5S rDNA loci are highly conserved in the proximal region of chromosome 8. Comparison of seventy-one IGS sequences in plants revealed several conserved motifs with potential regulatory function. The AT- and GC-rich domains appeared highly conserved in Cestrum chromosomes. The 5S genic and the GC-rich IGS probe produced FISH signals in both A (pair 8) and B chromosomes. The GC-rich domain presented a strong potential for regulation because it may be associated with CpG islands organization, as well as to hairpin and loop organization. Another interesting aspect was the ability of AT- and GC-rich motifs to produce non-heterochromatic CMA/DAPI signals. While the length of the 5S rDNA IGS region varied in size between the Cestrum species, the individual sequence motifs seem to be conserved suggesting their regulatory function. The most striking feature was the conserved GC-rich domain in Cestrum, which is recognized as a signature trait of the proximal region of chromosome pair 8. [ABSTRACT FROM AUTHOR]

The sand lances (also known as sand-eels) are small fish belonging to family Ammodytidae that consists of 31 species belonging to 7 genera. Despite world-wide distribution, key role in the ecosystems and significant commercial importance, sand lances have rarely been objects of the cytogenetic studies. The chromosomes of small sand-eel (Ammodytes tobianus) and great sand-eel (Hyperoplus lanceolatus) were analysed for this study. Karyotypes of both species were composed of 48 acrocentric chromosomes (FN = 48). Chromosomes of the great sand-eel were stained equally with DAPI. However, small sand-eels exhibited one pair of chromosomes with DAPI-negative blocks of chromatin located on the q-arm in the vicinity of the centromeric regions. Major and minor rDNA sites were observed on the separate single chromosome pairs in both species. These results provide new data regarding the genetics of Ammodytidae, showing an ancestral teleostean type of karyotype, based on the number of chromosomes (48), their morphology (FN = 48) and the distribution of rDNA sequences. [ABSTRACT FROM AUTHOR]

Three populations of neotylenchid nematodes were isolated in Ningbo, P. R. China, from white pine lumber (Pinus monticola) imported from the USA. The nematodes were morphologically intermediate between Hexatylus and Deladenus. The nematodes were molecularly characterized based on sequences of the rDNA small subunit 18S, large subunit 28S D2/D3, and internal transcribed spacer sequences. The phylogenetic inferences placed the nematodes with other neotylenchid nematodes, i.e., Fergusobia and Rubzovinema. Based on the morphology and phylogenetic analysis, this nematode is described herein as Delatylus andersoni n. gen., n. sp. The new genus/ species is characterized by the female body habitus ranging from nonobese to semiobese and from straight to dorsally curved when heat relaxed, cephalic framework with six unequal sized lip sectors, lateral fields having 10 to 12 lines, 4 to 5 guide rings on the stylet, excretory pore posterior to the nerve ring, spermatheca diminished or absent, vulvar opening large, and relative proximity of vulva to the anus. Detailed morphological and molecular characterization of the new genus/species is presented along with the comparison of the related genera. [ABSTRACT FROM AUTHOR]

Environmental sampling yielded two yeast species belonging to Microstromatales (Exobasidiomycetes, Ustilaginomycotina). The first species was collected from a leaf phylloplane infected by the rust fungus Coleosporium plumeriae, and represents a new species in the genus Jaminaea, for which the name Jaminaea rosea sp. nov. is proposed. The second species was isolated from air on 50% glucose media and is most similar to Microstroma phylloplanum. However, our phylogenetic analyses reveal that species currently placed in Microstroma are not monophyletic, and M. phylloplanum, M. juglandis and M. albiziae are not related to the type species of this genus, M. album. Thus, Pseudomicrostroma gen. nov. is proposed to accommodate the following species: P. glucosiphilum sp. nov., P. phylloplanum comb. nov. and P. juglandis comb. nov. We also propose Parajaminaea gen. nov. to accommodate P. albizii comb. nov. and P. phylloscopi sp. nov. based on phylogenetic analyses that show these are not congeneric with Jaminaea or Microstroma. In addition, we validate the genus Jaminaea, its respective species and two species of Sympodiomycopsis and provide a new combination, Microstroma bacarum comb. nov., for the anamorphic yeast Rhodotorula bacarum. Our results illustrate non-monophyly of Quambalariaceae and Microstromataceae as currently circumscribed. Taxonomy of Microstroma and the Microstromataceae is reviewed and discussed. Finally, analyses of all available small subunit rDNA sequences for Jaminaea species show that J. angkorensis is the only known species that possess a group I intron in this locus, once considered a potential feature indicating the basal placement of this genus in Microstromatales. [ABSTRACT FROM AUTHOR]

Aporocotyle mariachristinae n. sp. and A. ymakara Villalba & Fernández, 1986 were collected from the bulbus arteriosus and ventral aorta of pink cusk-eels, Genypterus blacodes (Forster, 1801) from Patagonia, Argentina. A. mariachristinae n. sp. can be distinguished from all the species of Aporocotyle by the asymmetrical extension of posterior caeca (right posterior caecum longer, terminating at the area between mid-level of ovary and posterior body end; left posterior caecum shorter, terminating at the area between mid-level of cirrus sac and posterior to reproductive organs), the distribution of spines along the ventro-lateral body margins and the number of testes. The new species clearly differs from A. ymakara, from the same host species, in the esophagus / body length ratio, the absence of distal loops at caeca, the anterior caeca / posterior caeca length ratio, and the number of testes. Additionally, in A. ymakara the left posterior caecum may be longer than right posterior caecum, while in the new species left posterior caecum is always shorter. The specimen of A. ymakara collected from Argentina is also described. We also provide observations of the distribution of spines in different species of Aporocotyle, including new specimens of A. argentinensis Smith, 1969 from Merluccius hubbsi Marini, 1933. Molecular sequence data obtained from partial 18S and 28S rDNA regions were compared between the new species and other two species of Aporocotyle (A. argentinensis and A. spinosicanalis Williams, 1958). This is a new locality record for A. ymakara, extending the known geographical distribution for this species from Chile to Argentina, and the first report of two species of Aporocotyle in the same host species and locality.

On a global basis, potato cyst nematodes ( Globodera spp. Skarbilovich 1959 [Behrens 1975]) are one of the most serious soilborne pathogens in potato ( Solanum tuberosum L.) production. In 2019 to 2020, 188 soil samples were taken from rhizosphere soil associated with the roots of stunted and chlorotic potato plants in the main potato-growing areas of Yunnan and Sichuan Provinces of China. Globodera rostochiensis Wollenweber 1923 (Skarbilovich 1959) was recovered from 112 of the samples. Nematode identification was as confirmed by morphometric, light microscopy, electron microscopy, and molecular methodologies. Population densities of G. rostochiensis ranged from 47.0 to 69.0 eggs/g of soil. A BLASTn homology search program was used to compare the sequences of populations of G. rostrochienses from Yunnan and Sichuan Provinces with populations of other Heteroderinae spp. and populations of G. rostochiensis from other nations. Although potato has been grown in China for at least 400 years and the nation produces more potato than any other country, potato cyst nematodes were not reported in China until 2022.

Meiotic chromosomes obtained from members of the coleopteran subfamilies Rutelinae and Dynastinae were studied using standard and silver nitrate staining, C-banding, base-specific fluorochromes and fluorescent in situ hybridization (FISH). The study presents detailed karyotipic descripitions of three Rutelinae species (Geniates borelli, Macraspis festiva and Pelidnota pallidipennis), and two Dynastinae species (Lygirus ebenus and Strategus surinamensis hirtus) with special emphasis on the distribution and variability of constitutive heterochromatin and the nucleolar organizer region (NOR). We found that for G. borelli, P. pallidipennis, L. ebenus and S. s hirtus the karyotype was 2n = 20 (9II + Xy p), with G. borelli, P. pallidipennis and L. ebenus showed meta-submetacentric chromosomes which gradually decreased in size. For Macraspis festiva the karyotype was 2n = 18 (8II + Xy p). In L. ebenus we found that the NOR was located on an autosome, but in the other four species it occurred on the sex bivalents. In all five species the constitutive heterochromatin (CH) was predominantly pericentromeric while the X chromosomes were almost completely heterochomatic, although CMA3/DA/DAPI staining showed intra and interspecific variation in the bright fluorescence of the constitutive heterochromatin. The FISH technique showed rDNA sites on the X chromosome of the Rutelinae species.

The aim of this study was to describe mitotic and meiotic chromosomes of Cycloneda sanguinea using C-banding, fluorescent in situ hybridization (FISH) rDNA probes, and sequential FISH/Ag-NOR staining. The chromosome number was 2n = 18 + XX for females and 2n = 18 + Xy for males. The X chromosome was metacentric and the Y chromosome was very small. During meiosis, the karyotypic meioformula was n = 9 + Xy p, and sex chromosomes configured a parachute at metaphase I. At the beginning of pachytene, bivalents were still individualized, and sex chromosomes were associated end-to-end through the heteropycnotic region of the X chromosome. Later in pachytene, further condensation led to the formation of a pseudo-ring by the sex bivalent. All chromosomes showed pericentromeric heterochromatin. FISH and sequential FISH/Ag-NOR staining evidenced the location of the nucleolar organizer region in one pair of autosomes (at spermatogonial metaphase). During meiosis, these genes were mapped to a region outside the sex vesicle by FISH, although Xy p was deeply stained with silver at metaphase I. These results suggest that these argyrophilic substances are of a nucleolar protein nature, and seem to be synthesized by a pair of autosomes and imported during meiosis (prophase I) to the sex pair, during the association of the sex chromosomes.

We are reporting on the utilization of high-throughput sequencing and different sequencing analysis tools to delineate identification of different isolates of the stripe rust fungal pathogen Puccinia striiformis f. sp. tritici (Pst). Different approaches are shown: utilization of rDNA sequences and random sequences that may be very useful to make sure that isolates belong to Pst and to distinguished closely related isolates. Identification of unique/lost sequences could lead to the identification of effectors associated with specific isolates., (© 2023. His Majesty the King in Right of Canada, as represented by the Minister of Agriculture and Agri-Food.)

Ganoderma includes species of great economic and ecological importance, but taxonomists judge the current nomenclatural situation as chaotic and poorly studied in the neotropics. From this perspective, phylogenetic analyses inferred from ribosomal DNA sequences have aided the clarification of the genus status. in this study, 14 specimens of Ganoderma and two of Tomophagus collected in Brazil were used for DNA extraction, amplification and sequencing of the iTS and LSU regions (rDNA). The phylogenetic delimitation of six neotropical taxa (G. chalceum, G. multiplicatum, G. orbiforme, G. parvulum, G. aff. oerstedtii and Tomophagus colossus) was determined based on these Brazilian specimens and found to be distinct from the laccate Ganoderma from Asia, Europe, North America and from some specimens from Argentina. Phylogenetic reconstructions confirmed that the laccate Ganoderma is distinct from Tomophagus, although they belong to the same group. The use of taxonomic synonyms Ganoderma subamboinense for G. multiplicatum, G. boninense for G. orbiforme and G. chalceum for G. cupreum was not confirmed. However, Ganoderma parvulum was confirmed as the correct name for specimens called G. stipitatum. Furthermore, the name G. lucidum should be used only for European species. The use of valid published names is proposed according to the specimen geographical distribution, their morphological characteristics and rDNA analysis. [ABSTRACT FROM AUTHOR]

Wittrockiella lyallii is a poorly known green macroalga that has been regarded as endemic to southern New Zealand. A herbarium specimen from southern Chile was discovered that conforms to the description of W. lyallii. Subsequently, it was realised that the South American species Cladophoropsis brachyartra is morphologically and ecologically equivalent to W. lyallii. Sequences of three ribosomal genes, including the internal transcribed spacer, from material collected in Chile and New Zealand are identical, suggesting recent long-distance dispersal from New Zealand to South America. The synonymisation of C. brachyartra with W. lyallii is presented here. Furthermore, the resulting disjunct distribution of the species is discussed in the light of sea surface temperatures, habitat availability in the Southern Ocean and winter sea ice extent during the last glacial maximum. [ABSTRACT FROM AUTHOR]

ITS1, the 5.8S rRNA gene and ITS2 of the rDNA region were sequenced from 20 different Pratylenchus species. Additionally, the same region was sequenced from seven populations of P. penetrans. After purifying, cloning and sequencing the PCR products, all sequences were aligned in order to find unique sites suitable for the design of species-specific primers for P. penetrans. Since ITS regions showed variability between and even within populations of P. penetrans, only three small DNA sequences were suitable for the construction of three potentially useful species-specific primers. New species-specific primers were paired with existing universal ITS primers and tested in all possible primer combinations. The best performing primer set, supplemented with a universal 28S rDNA primer set that served as an internal control, was tested in duplex PCR. The ideal annealing temperature, Mg2+ concentration and primer ratios were then determined for the most promising primer set. The optimised duplex PCR was subsequently tested on a wide range of different Pratylenchus spp. and 25 P. penetrans populations originating from all over the world. To test the sensitivity, the duplex PCR was conducted on DNA extracted from a single P. penetrans nematode mixed with varying amounts of nematodes belonging to another Pratylenchus species. Results showed that a reliable and sensitive P. penetrans species-specific duplex PCR was constructed. [ABSTRACT FROM AUTHOR]

A new species Ganoderma carocalcareus (Basidiomycota, Ganodermataceae) was collected on living trunk and dead stumps of Anthocleista nobilis (Gentianaceae) in waterlogged swamps in the Mbalmayo Forest Reserve, Cameroon, and identified on the basis of morphology and phylogenetic analyses inferred from mitochondrial small subunit (mtSSU) and internal transcribed spacer (ITS1-5.8S-ITS2) rDNA sequences. Distinct phenotypic characteristics of the new species are dimorphism of basidiomata and variability in context structure and texture over developmental stages. The young basidiomata is ungulate to punk-shaped with context composed of vegetative hyphae attended by scattered, orbicular, smooth, thick-walled chlamydospores, and the mature basidiomata is cushion- to bracket-like with context entirely consisting of chlamydospores masses. This ontogeny intimates the origin of chlamydospores, for which the biogenesis correlates the vanishing of vegetative hyphae throughout the basidiomata maturation. Morphological comparison included Tomophagus colossus (= G. colossus), G. subamboinense and G. weberianum, the known Ganodermataceae species producing chlamydospores and or gasterospores in basidiomata tissues, and G. resinaceum, the closest species with regard to morphology. It followed that G. carocalcareus could not be assigned to these or any other known Ganoderma species. Analyses of mtSSU and ITS rDNA sequence data resolved G. carocalcareus in the G. resinaceum group as a distinct species, but being a close relative of both G. subamboinense and G. weberianum. [ABSTRACT FROM AUTHOR]

Abstract: Ginseng (Panax quinquefolius L.) is widely cultivated in North America as a medicinal herb. However, yields are often reduced by various root pathogens, including Pythium species, which cause damping-off in young plants. In order to improve the prediction of disease risk, real-time PCR assays were developed and used in conjunction with dilution plating on selective media to quantify populations of Pythium irregulare Buisman and Pythium ultimum Trow directly from soil. The assays were tested on artificially infested soils and then used on a variety of naturally infested, ginseng-cultivated soils in south-western Ontario. Data on P. ultimum DNA concentrations were positively correlated with the number of P. ultimum viable propagules on selective media. However, in the case of P. irregulare, the presence of cryptic species resulted in incongruent relationships between the dilution plate and real-time PCR data. We therefore sequenced the ITS region of a large number of P. irregulare isolates in order to determine the proportion that would be detected by the real-time PCR assay. The ability to quantify pathogen populations directly from soils using real-time PCR (calibrated with data on inoculum potential) will improve disease risk assessment and lead to a reduction in pesticide application. [Copyright &y& Elsevier]

A basidiomycetous anamorphic yeast-like fungus, isolated from new bamboo shoots collected in Japan, was assigned to Meira argovae by comparison of conidial morphology, physiological characteristics, rDNA sequences, and DNA-DNA relatedness with the ex-type strains of Meira species. This is the first record of the finding of M. argovae from other than mite cadavers and in regions other than Israel. Phylogenetic analysis based on the D1-D2 domain demonstrated that Meira species and teleomorphic Dicellomyces species, which include a bamboo leaf parasite, D. gloeosporus, formed sister clades. [ABSTRACT FROM AUTHOR]

Abstract: Few basidiomycetes are known to have a coelomycete anamorph. The partial SSU and LSU of nu-rDNA of three coelomycete genera (Chaetospermum, Giulia, Mycotribulus) were sequenced to determine their phylogenetic relationship. M. mirabilis was well placed in the Physalacriaceae, Agaricales, whereas G. tenuis clusters with the Corticiaceae, Corticiales. C. camelliae and C. artocarpi form a close relationship with the Sebacinaceae, Sebacinales. Although morphologically these coelomycetes are pycnidial and with appendaged conidia, they show no consistency in their phylogenetic relationship, belonging to disparate major taxonomic groups with putative teleomorphs in the Agaricales, Corticiales and Sebacinales. Further molecular studies of coelomycetes may be rewarding to evaluate their phylogenetic affinities. [Copyright &y& Elsevier]

We studied the relationships between assemblages of soil microfungi and plant communities in the southern boreal mixed-wood forests of Québec. Sampling took place in 18 100 m² plots from an existing research site. Plots were separated into three categories based on dominant overstory tree species: (i) trembling aspen, (ii) white birch and (iii) a mixture of white spruce and balsam fir. Within each plot a 1 m² subplot was established in which the understory herbaceous layer was surveyed and soil cores were collected. Microfungi were isolated from soil cores with the soil-washing technique and isolates were identified morphologically. To support our morphological identifications DNA sequences were obtained for the most abundant microfungi. The most frequently occurring microfungal species were Penicillium thomii, P. spinulosum, P. janthinellum, Penicillium sp., P. melinii, Trichoderma polysporum, T. viride, T. hamatum, Mortierella ramanniana, Geomyces pannorum, Cylindrocarpon didymum, Mortierella sp. and Mucor hiemalis. Multivariate analyses (redundancy analysis followed by variance partitioning) revealed that most of the variation in microfungal communities was explained by understory plant species composition as opposed to soil chemistry or overstory tree species. In this floristically diverse system saprophytic microfungal assemblages were not correlated with the overstory tree species but were significantly correlated with the main understory herbs, thereby reflecting differences at a smaller spatial scale. [ABSTRACT FROM AUTHOR]

The lichenicolous basidiomycete Marchandiomyces corallinus is widely distributed in North America and Europe, where it commonly is found on a variety of lichens. Theoretically either of these characteristics, a wide geographic range or generalized host ecology, could provide opportunities for genetic differentiation within this species. To determine how genetic variation is partitioned in M. corallinus, 12 fungal isolates were obtained from locations in North America and Europe; at two locations, in Washington County, Maine, and on the Isle of Mull in Scotland, fungi also were isolated from different lichen hosts. Vegetative mycelial compatibility tests were used to determine compatibility groupings from among the isolates; in addition, several PCR amplification products (RAPD, nuITS rDNA) were obtained for each isolate. A number of distinct compatibility groups were recognizable based on geography, not host ecology. In addition compatible isolates always were restricted to either North America or Europe. However RAPD markers indicated that compatible isolates are not always genetically identical. The presence of sequence heterozygosity at specific positions indicated that the isolates are heterokaryotic and a number of distinct haplotypes could be identified based on ITS variation at three separate locations. This type of genetic variation in these fungi suggests that sexual recombination is possible and that genetic differentiation has taken place recently as a result of geographic isolation, not host switching. [ABSTRACT FROM AUTHOR]

Phylogenies inferred from the analysis of DNA sequence data have shown that the Onygenales contains clades that do not correspond with previously described families. One lineage identified in recent molecular phylogenetic studies includes the dimorphic pathogens belonging to the genera Ajellomyces, Emmonsia and Paracoccidioides. To evaluate the degree of support for this lineage and determine whether it includes additional taxa, we examined relationships among the members of this clade and selected saprobic onygenalean taxa based on maximum-parsimony analyses of partial nuclear large RNA subunit (LSU) and internal transcribed spacer (ITS) sequences. A clade distinct from the Onygenaceae was found to encompass Ajellomyces (including the anamorph genera Blastomyces, Emmonsia and Histoplasma) and Paracoccidioides brasiliensis. The members of this lineage are saprobic and pathogenic vertebrate-associated taxa distinguished by their globose ascomata with coiled appendages, muricate globose or oblate ascospores, and lack of keratinolytic activity. Anamorphs are solitary aleurioconidia or irregular alternate arthroconidia. Based on molecular data and on morphological and physiological similarities among these taxa, we propose the new family, Ajellomycetaceae. [ABSTRACT FROM AUTHOR]

The basidiomycete C30 was considered as an isolate of a population of Marasmius quercophilus collected on evergreen oak litter from the Mediterranean forest. Recent phenotypic studies have clearly shown that it differs from newly characterized M. quercophilus isolates. Subsequent analysis of laccase genes revealed that C30 sequences are similar to laccase encoding sequences from organisms belonging to the polyporoid clade. Comparison of sequences of the C30 ITS regions, including 5.8S rDNA, with those found in databanks confirmed that C30 is not a Marasmius. Finally, 25S rDNA analysis revealed that C30 is closely related to the Coriolaceae and, in particular, to Trametes trogii. [Copyright &y& Elsevier]

Four forms of Colletotrichum representing three distinct virulence phenotypes were found associated with foliar anthracnose of yam in Nigeria: the highly virulent (= severity of disease) slow-growing grey (SGG); the moderately virulent fast-growing salmon (FGS); the weakly virulent fast-growing grey (FGG); and the moderately virulent fast-growing olive (FGO) morphotype. Isolates of the four forms were identified as C. gloeosporioides , based on morphology. The reaction of monoconidial cultures on casein hydrolysis medium (CHM), PCR-RFLP and sequence analysis of the internal transcribed spacer region of the ribosomal DNA (ITS1-5·8S-ITS2) were used to establish the identity of the yam anthracnose pathogen(s). All yam isolates were distinguished from C. acutatum by the absence of protease activity on CHM. On ITS PCR and enzymatic digestion of PCR products, all FGS, FGO and SGG isolates produced RFLP patterns identical to those of C. gloeosporioides reference isolates, while FGG isolates revealed unique ITS RFLP banding patterns. Sequence analysis of the ITS1 region and of the entire ITS region revealed that SGG, FGS and FGO isolates were highly similar (98–99% nucleotide identity) and showed 97–100% identity to C. gloeosporioides . Less than 93% similarity of these fungal isolates to reference C. acutatum and C. lindemuthianum isolates was observed. The molecular study confirmed that foliar anthracnose of yam is caused by C. gloeosporioides . While a high similarity was found among most C. gloeosporioides fungi from yam, isolates of the FGG form did not cluster with any previously described Colletotrichum species, and probably represent a distinct species. [ABSTRACT FROM AUTHOR]

A molecular phylogenetic study of the genus Cyclamen L. (Primulaceae) has been undertaken, based on sequence data from the 5.8S gene in the ribosomal nuclear DNA and its flanking internal transcribed spacers ITS1 and ITS2. Sequence data from 15 species of Cyclamen and seven outgroup taxa selected from Primulaceae and Myrsinaceae were analyzed phylogenetically. A second analysis based on a combined morphological and molecular dataset was performed to evaluate earlier hypotheses of character evolution in the genus. The results indicate that four monophyletic subgroups may be recognized in the genus, viz. Cyclamen, Psilanthum Schwarz, Eucosme Schwarz and Gyrophoebe Schwarz. Each of the four subgenera is diagnosed by distinct basic chromosome number, as well as by morphological and molecular characteristics. [ABSTRACT FROM AUTHOR]

Phylogenetic relationships of the Poaceae subfamily, Pooideae, were estimated from the sequences of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA. The entire ITS region of 25 species belonging to 19 genera representing seven tribes was directly sequenced from polymerase chain reaction (PCR)-amplified DNA fragments. The published sequence of rice, Oryza saliva, was used as the outgroup. Sequences of these taxa were analyzed with maximum parsimony (PAUP) and the neighbor-joining distance method (NJ). Among the tribes, the Stipeae, Meliceae and Brachypodieae, all with small chromosomes and a basic number more than x=7, diverged in succession. The Poeae, Aveneae, Bromeae and Triticeae, with large chromosomes and a basic number of x=7, form a monophyletic clade. The Poeae and Aveneae are the sister group of the Bromeae and Triticeae. On the ITS tree, the Brachypodieae is distantly related to the Triticeae and Bromeae, which differs from the phylogenies based on restriction-site variation of cpDNA and morphological characters. The phylogenetic relationships of the seven pooid tribes inferred from the ITS sequences are highly concordant with the cytogenetic evidence that the reduction in chromosome number and the increase in chromosome size evolved only once in the pooids and pre-dated the divergence of the Poeae, Aveneae, Bromeae and Triticeae. This paper reports factually on available data; however, the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also be suitable [ABSTRACT FROM AUTHOR]

Supernumerary B chromosomes (Bs) are very promising structures, among others, in that they are an additional genomic compartment for evolution. In this study, we tested the presence and frequency of B chromosomes and performed the first cytogenetic examination of the common nase (Chondrostoma nasus). We investigated the individuals from two populations in the Vistula River basin, in Poland, according to the chromosomal distribution of the C-bands and silver nucleolar organizer regions (Ag-NORs), using sequential staining with AgNO3 and chromomycin A3 (CMA3). Furthermore, we analyzed the chromosomal localization of two rDNA families (45S and 5S rDNA) using fluorescence in situ hybridization (FISH) with rDNA probes. Chondrostoma nasus individuals showed a standard (A) chromosome set consisting of 2n = 50: 12 metacentric, 32 submetacentric, and 6 acrocentric chromosomes (NF = 94). Fourteen out of the 20 analyzed individuals showed 1–2 mitotically unstable submetacentric B chromosomes of different sizes. Six of them, in 14.1% of the analyzed metaphase plates, had a single, medium-sized submetacentric B (Bsm) chromosome (2n = 51) with a heterochromatic block located in its pericentromeric region. The other seven individuals possessed a Bsm (2n = 51) in 19.4% of the analyzed metaphase plates, and a second Bsm chromosome (2n = 52), the smallest in the set, in 15.5% of metaphase plates, whereas one female was characterized by both Bsm chromosomes (2n = 52) in 14.3% of the analyzed metaphase plates. AgNORs, GC-rich DNA sites, and 28S rDNA hybridization sites were observed in the short arms of two submetacentric chromosome pairs of A set. The constitutive heterochromatin was visible as C bands in the centromeric regions of almost all Chondrostoma nasus chromosomes and in the pericentromeric region of several chromosome pairs. Two 5S rDNA hybridization sites in the pericentromeric position of the largest acrocentric chromosome pair were observed, whereas two other such sites in co-localization on a smaller pair of NOR chromosomes indicate a species-specific character. The results herein broaden our knowledge in the field of B chromosome distribution and molecular cytogenetics of Chondrostoma nasus: a freshwater species from the Leuciscidae family. [ABSTRACT FROM AUTHOR]

Three populations of neotylenchid nematodes were isolated in Ningbo, P. R. China, from white pine lumber (Pinus monticola) imported from the USA. The nematodes were morphologically intermediate between Hexatylus and Deladenus. The nematodes were molecularly characterized based on sequences of the rDNA small subunit 18S, large subunit 28S D2/D3, and internal transcribed spacer sequences. The phylogenetic inferences placed the nematodes with other neotylenchid nematodes, i.e., Fergusobia and Rubzovinema. Based on the morphology and phylogenetic analysis, this nematode is described herein as Delatylus andersoni n. gen., n. sp. The new genus/species is characterized by the female body habitus ranging from nonobese to semiobese and from straight to dorsally curved when heat relaxed, cephalic framework with six unequal sized lip sectors, lateral fields having 10 to 12 lines, 4 to 5 guide rings on the stylet, excretory pore posterior to the nerve ring, spermatheca diminished or absent, vulvar opening large, and relative proximity of vulva to the anus. Detailed morphological and molecular characterization of the new genus/species is presented along with the comparison of the related genera.