黑龙江省蹄盖蕨科(Athyriaceae)植物的RAPD分析及其系统学意义

在形态分类研究的基础上,利用RAPD技术,对黑龙江省蹄盖蕨科植物6属9种共15个种群进行了遗传多样性分析,分析结果表明：（1）假冷蕨属应包括在蹄盖蕨属中（2）角蕨属与蹄盖蕨属,羽节蕨属与冷蕨属亲源关系较近（3）短肠蕨属为独立一属,与其它属亲源关系较远。根据黑龙江省蹄盖蕨科植物的DNA水平的研究结果,再结合其形态学特征,建议将黑龙江省蹄盖蕨科划分为3个亚科：冷蕨亚科(Cystopterioideae)包括2个属：冷蕨属(Cystopteris)和羽节蕨属(Gymnocarpium)。蹄盖蕨亚科(Athyrioideae)包括3个属：蹄盖蕨属(Athyrium)、假冷蕨属(Pseudocystopteris)和角蕨属(Cornopteris)。双盖蕨亚科(Diplazioideae)包括短肠蕨属(Allantodia)。     

Classification ofAthyrium and allied genera of Japan

The classification ofAthyrium sensu lato is revised on the basis of evidence from anatomical and morphological observations. Although parallelism is found in several characteristics, stipe base, groove of frond axis, laminar margin, venation, sorus and dermal appendage are important to classify the genus and elucidate the relationship within it.Athyrium sensu lato is divided into four generaAthyrium, Cornopteris, Deparia andDiplazium, small genera being referred toAthyrium orDiplazium, Deparia is construed in a broad sense to includeAthyriopsis, Dryoathyrium andLunathyrium. The four genera with infrageneric groups or sections are described in detail. Among the genera,Athyrium, particularly theA. puncticaule group, may be considered to have primitive characteristics, andCornopteris may have been derived fromAthyrium by abortion of the indusia.Cystopteris is also related toAthyrium on the basis of reniform sori inC. douglasii.     

On the systematic position of the Early Cretaceous fern genus “Athyrium”

The oldest fossils assigned to Athyrium (mostly based on the sorus morphology) comprise fronds and spores from the Lower Cretaceous of Northeast Asia. However, most molecular dating suggests that extant Athyrium diverged from its sister genus during the Eocene or later, implying that the Cretaceous fossils probably belong to another polypodiaceous taxon. By examining the sorus morphology of extant genera related to the family Athyriaceae, we found that the primary diagnostic feature for assigning the Cretaceous fossils to Athyrium, i.e., the sorus shape, is common to the entire extant family, or plesiomorphic for the genus. As the fronds are more commonly preserved than the reproductive parts, we compared the fossil frond morphology with those of living taxa of the family that is divided into two types. The Cretaceous fossil we examined here bears the frond’s costal groove characters on adaxial side, which is more closely related to that of the Deparia-clade instead of the clade including Athyrium and other genera of the family. The observation is further confirmed by the cladistic analysis using morphological characters. The systematic position of the Early Cretaceous “Athyrium” was resolved as a stem member of the total Athyriaceae using a tip-dating approach with the Fossilized Birth-Death model in a Bayesian framework. Our study suggests that Early Cretaceous fossils previously assigned to Athyrium require taxonomic revision.     

<Emphasis Type="Italic">Athyrium crassicaule</Emphasis> (<Emphasis Type="Italic">Woodsiaceae</Emphasis>), a new fern species from the Drakensberg,southern Africa

Summary  A new Athyrium species, A. crassicaule J. P. Roux (Woodsiaceae), is described from the Drakensberg in Lesotho and South Africa. A key to the Athyrium species in Lesotho, South Africa and Swaziland is provided.     

Effect of altered snow conditions on decomposition in three subalpine plant communities

Snow cover and its spatio-temporal changes play a crucial role in the ecological functioning of mountains. Some human activities affecting snow properties may cause shifts in the biotic components of ecosystems, including decomposition. However, these activities remain poorly understood in subalpine environments. We explored the effect of human-modified snow conditions on cellulose decomposition in three vegetation types. Snow density, soil temperature, and the decomposition of cellulose were studied in Athyrium, Calamagrostis, and Vaccinium vegetation types, comparing stands intersected by groomed ski slope and natural (outside the ski slope) stands. Increased snow density caused the deterioration of snow insulation and decreased the soil temperature inside the ski slope only slightly in comparison with that outside the ski slope in all vegetation types studied. The decomposition was apparently lower in Athyrium vegetation relative to the other vegetation types and strongly (Athyrium vegetation) to weakly lower (other vegetation types) in groomed than in ungroomed stands. Wintertime, including the melting period, was decisive for overall decomposition. Our results suggest that differences in decomposition are influenced by ski slope operations and vegetation type. Alterations in snow conditions appeared to be subtle and long-term but with important consequences for conservation management.     

<Emphasis Type="Italic">Athyrium sessilipinnum</Emphasis>: A new lady fern (Athyriaceae) from southern China

A new species of Athyrium from southern China is described and illustrated as Athyrium sessilipinnum. Morphological comparisons among this new species and similar ones (e.g., A. arisanense, A. gedeanum, A. epirachis, and A. otophorum) are provided. Molecular evidence reveals a sister relationship between the new species and A. arisanense. The most distinctive characters of A. sessilipinnum are the sessile, non-pinnatifid and non-shortened pinnae.     

Evidence for intergeneric incompatibility in ferns

The archegonial mucilage ofAthyrium filix-femina andA. distentifolium paralyses spermatozoids ofDryopteris filix-mas (and in one caseD. inaequalis) before they penetrate the archegonial venter. The archegonial mucilage ofDryopteris filix-mas has a weak positive chemotactic influence on the spermatozoids of the twoAthyrium species. The spermatozoids ofDryopteris were never observed in the archegonia ofAthyrium. Incompatibility was not observed within and between the twoAthyrium species, withinDryopteris filix-mas or betweenAthyrium filix-femina and twoAsplenium species.Contribution No. 327.     

The Cytology of some Athyrium species from Northern India

The present investigation deals with the cytology of genus Athyriumfrom Northern India. Eleven species have been studied and comparisonswith the previous records are made. All the North Indian speciesare sexual and there is a lower percentage of polyploidy comparedwith the species in Ceylon. Their occurrence at high altitudessuggests that the temperate climate may be significant in thisconnexion. Polyploidy is noticed only up to the tetraploid leveland only in two cases.     

Lead tolerance and accumulation in the gametophytes of the fern Athyrium yokoscense

The fern Athyrium yokoscense is known to be highly tolerant to lead toxicity, and is a lead hyperaccumulator that can accumulate over 1,000 g g^–1 of lead in its dry matter. In this work, we examined whether the gametophytic generation of A. yokoscense also resists lead toxicity like the sporophytic generation. Spore germination in A. yokoscense was more tolerant to Pb²⁺, compared to that in other fern species, such as Pteridium aquilinum, Lygodium japonicum and Pteris vittata. In addition, the early gametophyte development of A. yokoscense was not much affected by 10 M Pb²⁺, as evaluated from the prothallial growth and rhizoid development. We also showed that Athyrium gametophytes could accumulate more than 10,000 g g^–1 of lead, and that the lead was localized in the cytosol and vacuole of rhizoidal cells, as determined by a transmission electron micrograph. These results indicate that Athyrium gametophytes have the ability to accumulate lead in the rhizoids. Furthermore, the gametophytes were found to include a large amount of proanthocyanidins (condensed tannins). Because proanthocyanidins have a latent ability to complex with lead ions, the possible roles of proanthocyanidins in the lead tolerance and accumulation of Athyrium gametophytes are discussed.     

15种蹄盖蕨科植物叶表皮形态特征的研究

利用光学显微镜对蹄盖蕨科15种植物的叶表皮形态特征进行观察和研究。结果表明:蹄盖蕨科15种植物的上、下表皮细胞均为无规则型,垂周壁为凹凸状或深波状;上表皮细胞长宽比在1.0~3.2之间,下表皮细胞长宽比在1.0~2.6之间;在这15种植物中共观察到6种气孔器类型,即极细胞型、腋下细胞型、聚合极细胞型、聚腋下细胞型、无规则四细胞型和无规则型,每种植物具有3~4种气孔器类型,气孔均为下生型,多呈椭圆形。气孔的长宽比在1.3~2.1之间;气孔密度在32~90个/mm2之间;气孔指数为17.7%~40.9%。依据上述叶表皮形态特征将15种蹄盖蕨科植物分为3类,即双盖蕨类、蹄盖蕨类和对囊蕨类。该研究在一定程度上支持Christenhusz分类系统对蹄盖蕨科的划分,为蹄盖蕨科植物的系统分类及演化研究提供基础资料。     

Hebeloma species associated with Cistus

The genus Hebeloma has a number of species highly specific to Cistus and others that occur with several host genera. This paper discusses the species of Hebeloma that appear to be ectomycorrhizal with Cistus, judging from their occurrence when Cistus is the only available host. The previously unknown species H. plesiocistum spec. nov. is described. We also provide a key to the known Hebeloma associates of Cistus. Molecular analyses based on ITS sequence data further illustrate the distinctness of the newly described species and difficulties in the species delimitation with view to H. erumpens. Specific associations with Cistus may have evolved more than once within the genus Hebeloma.     

Arbuscular mycorrhizas on Athyrium yokoscense and A. niponicum grown at a lead-contaminated site

To investigate the occurrence of arbuscular mycorrhizas (AM) and their morphological types, four Athyrium yokoscense and five A. niponicum individuals were collected at a lead-contaminated site. Three of the A. yokoscense and four of the A. niponicum formed AM structures. However, the percentage of AM formation within both species differed significantly among individuals. Morphological types of most AM structures were the Paris-type, except for one A. yokoscense that formed both Paris-type and Arum-type-like structures in different parts of the same root section. These results demonstrate that the two Athyrium species form AM associations in lead-contaminated soil.     

Chemotaxonomy and flavonoid profiling of Torilis species by HPLC/ESI/MS2

The flavonoid profiles of Turkish Torilis Gaertn. (Apiaceae) species were studied by TLC, HPLC-UV and HPLC/ESI/MS² (negative mode). O-glycosides of luteolin, apigenin and chrysoeriol were identified from crude extracts with the help of mass spectra in different MS/MS modes, such as full scan, precursor ion scan and product ion scan. Luteolin-7-O-glucoside and luteolin-7-O-rutinoside were common to all species. Flavonoid profiles usually differ from one species to another and can be put to use for a genus such as Torilis which has been little studied. By the help of different flavonoid profiles, it is concluded that, the plants, which are recognised as less rayed subspecies of Torilis arvensis (Huds.) Link. in various floras including Turkish one, must be classified in species category as Torilis chrysocarpa and Torilis purpurea. Flavonoid profiles seem to be in relation with evolutionary biogeography of the species. Because the most isolated species of the genus, endemic Torilis triradiata, has the most different flavonoid pattern. Moreover, geographically isolated species, T. triradiata and Torilis leptocarpa, do not share any flavonoid except for the two which are common to all species.     

Species delimitation in the European species of Clavulina (Cantharellales, Basidiomycota) inferred from phylogenetic analyses of ITS region and morphological data

The identification of the conventionally accepted species of Clavulina (Cantharellales, Basidiomycota) in Europe (Clavulina amethystina, Clavulina cinerea, Clavulina cristata, and Clavulina rugosa) is often difficult and many specimens are not straightforwardly assignable to any of those four species, which is why some authors have questioned their identity. In order to assess the status of those species, a morphological examination was combined with the molecular analysis of the ITS region. The same six major clades were obtained in the Bayesian and parsimony phylogenetic analyses, and all six clades were well-supported at least by one of the analyses. Morphological characters, such as the overall branching pattern, the presence and intensity of grey colour, the cristation of the apices, and basidiospore size and shape were to various extents correlated with the phylogenetic signal obtained from the ITS region. The congruence between the molecular analyses and morphology, rather than geographical origin, suggests the existence of several species that can be delimited using a combined phylogenetic and morphological species recognition. The analyses revealed that C. cristata and C. rugosa are well-delimited species. In contrast, more than one taxa could be subsumed under the names C. amethystina and C. cinerea, the taxonomical complexity of which is discussed. The ITS region is proved to be adequate to separate phylogenetic species of Clavulina.     

Genetic diversity and relationships among species of the genus Thymus L. (section Serpyllum)

Amplified fragment length polymorphism (AFLP) markers were used to assess genetic relations of 32 Thymus populations belonging to seven species of genus Thymus, section Serpyllum, from Serbia. The collected species belong to three subsections: (1) Alternantes Klokov (Th. pulegioides L.), (2) Isolepides (Borbás) Halácsy (Th. glabrescens Willd., Th. marschallianus Willd., Th. pannonicus All.), and (3) Pseudomarginati (Braun ex Borbás) Jalas (Th. balcanus Borbás, Th. moesiacus Velen., Th. praecox Opiz). Analysis of molecular variance (AMOVA) revealed that most of the genetic diversity was attributable to differences among individuals within populations, while the remaining variability was almost equally distributed among species and among populations within species. The pairwise AMOVA analyses further showed that species differentiation was significant in all cases, except between Th. marschallianus and Th. pannonicus. All the individuals belonging to Th. pulegioides (subsection Alternantes) formed a well-supported clade, the most divergent from all other species in this study. This genetic differentiation of Th. pulegioides is supported by its morphological features because it is the only analyzed taxon having hairs only on the stem edges, and can easily be recognized by this character. According to our results, the subsection Isolepides is polyphyletic. Th. glabrescens is clearly separated from the other two species of this subsection (Th. marschallianus, Th. pannonicus). Although morphologically distinguishable by leaf indumentum, individuals belonging to Th. marschallianus and Th. pannonicus could not be differentiated at the molecular level. The species belonging to subsection Pseudomarginati formed a monophyletic clade, although not supported by high bootstrap value. The clade is further divided into three well-supported clades representing distinct species (Th. balcanus, Th. praecox and Th. moesiacus). In our study, the AFLP markers demonstrated that they could be suitable for studying complex genetic relationships, including frequent interspecies hybridization events, although strict reticulate evolutionary history could not be determined. All the population genetic parameters in the section Serpyllum suggest that the reproductive incompatibility between the species is very weak, which indicates a strong reticulating system, especially in the case when two or more species occur sympatrically.     

Ceratocystidaceae exhibit high levels of recombination at the mating-type (MAT) locus

Mating is central to many fungal life cycles and is controlled by genes at the mating-type (MAT) locus. These genes determine whether the fungus will be self-sterile (heterothallic) or self-fertile (homothallic). Species in the ascomycete family Ceratocystidaceae have different mating strategies, making them interesting to consider with regards to their MAT loci. The aim of this study was to compare the composition of the MAT locus flanking regions in 11 species of Ceratocystidaceae representing four genera. Genome assemblies for each species were examined to identify the MAT locus and determine the structure of the flanking regions. Large contigs containing the MAT locus were then functionally annotated and analysed for the presence of transposable elements. Genes typically flanking the MAT locus in sordariomycetes were found to be highly conserved in the Ceratocystidaceae. The different genera in the Ceratocystidaceae displayed little synteny outside of the immediate MAT locus flanking genes. Even though species ofCeratocystis did not show much synteny outside of the immediate MAT locus flanking genes, species of Huntiella and Endoconidiophora were comparatively syntenic. Due to the high number of transposable elements present in Ceratocystis MAT flanking regions, we hypothesise that Ceratocystis species may have undergone recombination in this region.     

Nitrogen-containing non-steroidal secondary metabolites of Solanum, Cyphomandra, Lycianthes and Margaranthus

Of the 49 species of Solanum studied, cuscohygrine has been detected in 25, solamine and related amines in 17 and solamine-derived amides in 16. Five species of Cyphomandra examined all contained both amines and amides. From roots of Margaranthus solanaceus cuscohygrine has been isolated which probably occurs, too, in roots of Lycianthes rantonnettii. The distribution of these compounds throughout the taxa could be of chemotaxonomic value.     

The Pachycrocuta and Hyaena lineages (plio-pleistocene and extant species of the Hyaenidae). Their relationships with miocene ictitheres: Palhyaena and Hyaenictitherium

The large «crocutoïd hyaenas from the Plio-Pleistocenedeposits of Eurasia do not belong to the same lineage as the extant species Hyaena hyaena and must be referred to the genus PachycrocutaKretzoi, of which an emended diagnosis is given. This revision takes into account some undescribed or ill-known specimens from Russia, China and Africa. They definitely establish that Pachycrocuta ranged over Eurasia, from West Europe to East China, as early as the early Villafranchian at least, and that it was present in North Africa too; a large sample from the Odessa Catacombs affords an estimation of the intraspecific variation in the Ruscinian species, H. pyrenaica, known until now by only a few specimens from the western part of the Mediterranean basin, and it shows H. pyrenaica to be the ancestral form of the Villafranchian Eurasian species P. perrieri, from which derived P. brevirostris, the last species of the lineage, as previously shown by other authors.It appears that the “Hyaena lineage evolved simultaneously in Africa; we knew already that the root of this lineage is H. abronia, a species from the late Miocene of South Africa whose generic attribution is discussed relative to some Ictitheres from Shan-Si, Samos, Sahabi and Klein Zee. The hypothesis of a common African origin of the two lineages is not excluded, if not demonstrated. The relationships of the Pleistocene European species H. prisca and that of the extant African species H. brunnea are discussed.     

Diversity,host associations,and phylogeography of temperate aurofusarin-producing Hypomyces/Cladobotryum including causal agents of cobweb disease of cultivated mushrooms

Temperate species of Hypomyces and Cladobotryum that produce the red pigment aurofusarin are common on agaricoid and polyporoid basidiomata of species from five orders of Agaricomycetes. Several cause cobweb disease of commercially cultivated mushrooms resulting in serious losses. We sequenced rpb1, rpb2, tef1, and FG1093 regions in 90 wild strains and 30 strains from mushroom farms, isolated from Europe, North America, Africa, Asia, Australia, and New Zealand. Multigene analyses support the distinctness of five species but reveal Hypomyces rosellus to be paraphyletic, comprising several cryptic lineages. Hypomyces rosellus s. str. is characterised by wide dispersal and gene flow across Eurasia but does not occur in North America. Instead, the lineages from the West and the East Coast appear distinct, having given rise to species inhabiting the Southern Hemisphere. Our results reveal wide misuse of the name H. rosellus, especially for cobweb isolates. The majority of these belong to Hypomyces odoratus, including a weakly supported group of fungicide-resistant strains from Europe and North America sharing identical sequence data. New collections are presented for Cladobotryum rubrobrunnescens and Cladobotryum tenue as well as Cladobotryum multiseptatum and Hypomyces dactylarioides, all previously known only from their type material. The former species pair occurs in Europe and the latter in Australia and New Zealand. Separate lineages appear to be maintained by geographic isolation in North America and temperate Australasia but by host specialisation in the species occurring sympatrically in Europe and Asia. Both specialist and generalist host use strategies have evolved in the group. Although teleomorphs are known in most of the species and unnamed lineages, analyses of the five-gene regions suggest the prevalence of clonal reproduction in H. odoratus. This can be the reason for its success in mushroom farms, also facilitating the spread of fungicide resistance. While tef1 and rpb2 can be recommended for species delimitation, low variation, not exceeding 1 % in the whole ingroup, impeaches the use of ITS as a barcoding gene region in this group of fungi.