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1.
Uromyces appendiculatus, inclusive of three varieties, is distinguished from U. vignae primarily by the position of urediniospore germ pores and putative host specificity. However, opinions concerning these morphological and physiological features as taxonomic characters have varied greatly, and distinction of these species has often been confused. To clarify the taxonomy of these two species, morphological features of urediniospores and teliospores of 225 rust fungus specimens on species of Phaseolus, Vigna, Apios, Lablab, and Dunbaria were examined by light microscopy and scanning electron microscopy. Forty-five specimens were subjected to molecular phylogenetic analyses. As a result, the position of germ pores in urediniospores and the teliospore-wall thickness were considered as good characters to separate three morphological groups. In molecular analyses, the specimens fell into two and three clades based on the nucleotide sequence at D1/D2 domain of LSU rDNA and ITS regions, respectively. One of the D1/D2 clades corresponded to one morphological group whereas another D1/D2 clade included two other morphological groups. In contrast, each of the three ITS clades corresponded to a separate morphological group. Neither morphological groups nor molecular clades were host limited. It is suggested that the three morphological groups that corresponded to three distinct ITS clades constitute distinct species.Contribution no. 186 from the Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

2.
Heteroecious Phakopsora euvitis, P. vitis, and P. ampelopsidis, autoecious P. meliosmae, and an unconnected Aecidium on Meliosma are closely allied. A total of 45 collections representing the five rust fungi from Japan, Australia, and East Timor were subjected to molecular phylogenetic analyses: the D1/D2 region of nuclear large subunit rDNA and nuclear small subunit internal transcribed spacer 2 (ITS2) region including 5.8S rDNA were analyzed. Tree topologies generated from parsimony and distance methods of the D1/D2 and ITS2 sequences were similar. The 45 collections (44 for ITS2 and 33 for D1/D2, with 32 common for both analyses) are grouped into seven clades: P. ampelopsidis, P. vitis, unconnected Aecidium, P. euvitis from Japan, P. euvitis from Australia and East Timor, P. meliosmae on M. myriantha, and P. meliosmae on M. tenuis. The results confirm the phylogenetic distinctness of P. euvitis, P. ampelopsidis, and P. vitis distributed in Japan. A grapevine leaf rust fungus in Australia and East Timor has genetically diverged from P. euvitis in Japan. The unconnected Aecidium is highly likely to be an aecial anamorph of a Phakopsora fungus. Autoecious Phakopsora fungi on M. meliosmae and M. tenuis need further host-specificity and morphological studies to confirm their taxonomic status.  相似文献   

3.
A new species of the genus Rhodotorula was isolated from a tubeworm (Lamellibrachia sp.) collected at a depth of 1156 m in Sagami Bay, Japan. Strain SY-89 had physiological properties quite similar to R. aurantiaca. Two phylogenetic trees, one based on internal transcribed spacer (ITS) regions and 5.8S rDNA sequences and the other based on the D1/D2 region of the large subunit (26S) rDNA sequences, united strain SY-89 to the type strain of Sakaguchia dacryoides through a considerable evolutionary distance. Strain SY-89 was differentiated from S. dacryoides by the G+C content of the nuclear DNA and differences in the ability to utilize specific carbon and nitrogen compounds. The low complementarity of strain SY-89 DNA to that of the type strain of S. dacryoides confirmed that this strain was genetically unrelated to previously known species. The tubeworm isolates are described as R. lamellibrachii sp. nov. The type strain of R. lamellibrachii is strain SY-89 (= JCM 10907). R. lamellibrachii formed a cluster with Erythrobasidium hasegawianum, R. lactosa, S. dacryoides and Sporobolomyces elongatus on the ITS and 5.8S rDNA phylogenetic tree. These five species shared a signature sequence in 26S rDNA, although this relationship was not supported by phylogeny based on the D1/D2 region of 26S rDNA.  相似文献   

4.
A basidiomyetous yeast strain RO-203, which formed orange-red colored colonies, was isolated from a sample of paddy rice crops at the ripe stage in Japan. Morphological, physiological and biochemical characterization indicated that this strain belonged to the genus Rhodotorula. Molecular taxonomic analysis based on the 26S rDNA D1/D2 domain and internal transcribed spacer (ITS) region sequences showed that RO-203 represents an undescribed yeast species, for which the name Rhodotorula oryzae sp. nov. is proposed (type strain: AS 2.2363T = MAFF 516128T). The new species clustered in a branch together with Sakaguchia dacryoidea in phylogenetic trees based on the D1/D2 and ITS sequences. These two species differed by 2.3% and 12% nucleotide divergences in the D1/D2 and ITS regions, respectively.  相似文献   

5.
Many species of Melampsora on Populus have been reported in China, based on morphological characteristics of both uredial and telial states, and on host species, but their morphology and taxonomy are still poorly defined. In this study, 196 specimens representing Melampsora species on poplars and collected from various areas of China were used for morphological observations. The morphological characteristics of urediniospores and teliospores were examined with light and scanning electron microscopy. The specimens could be classified into five groups based on their morphology. For the sequencing of the nuclear large subunit rDNA (D1/D2), 5.8S rDNA and their internal transcribed spacers, ITS1 and ITS2 region, 54 specimens were selected from the specimens used in morphological observations. These specimens were separated into six clades by phylogenetic analyses of the D1/D2 and ITS regions. Correlations among morphological groups and phylogenetic clades based on these results suggest a revision of these species. In particular, no evidence to discriminate specimens of M. acedioides, M. magnusiana, and M. rostrupii was found from either morphological characteristics or sequence analysis.Contribution no. 185 Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

6.
Three undescribed strains of basidiomycetous, anamorphic yeastlike fungi were isolated from Japanese pear fruits with a reddish stain collected in Tottori Prefecture, Japan. The strains are classified in a single group and assigned to the genus Meira by conventional and chemotaxonomic studies. Sequence analyses of the D1/D2 domain of 26S rDNA and internal transcribed spacer (ITS) regions indicate that the strains represent a novel species with a close phylogenetic relationship to Meira geulakonigii and M. argovae. The name Meira nashicola sp. nov. is proposed for the strains (type strain PFS 002 = MAFF 230028 = CBS 117161).  相似文献   

7.
We studied the morphology and molecular phylogeny of Myoschiston duplicatum, a peritrich ciliate that has been recorded as an epibiont of crustaceans, but which we also identified on marine algae from Korea. The important morphological characteristics revealed by silver staining of Myoschiston species have not been described because they are rarely collected. Using morphological methods, we redescribed the type species of the genus, Myoschiston duplicatum, and provided an improved diagnosis of Myoschiston. In addition, the coding regions for nuclear small subunit (SSU) rRNA and internal transcribed spacer 1‐5.8S‐internal transcribed spacer 2 sequences were sequenced. Phylogenetic analyses that included available SSU rDNA sequences of peritrichs from GenBank strongly supported a position of M. duplicatum within the family Zoothamniidae. In addition, phylogenetic analyses were performed with single datasets (ITS1‐5.8S‐ITS2) and combined datasets (SSU rDNA + ITS1‐5.8S‐ITS2) to explore further the phylogenetic relationship in the family Zoothamniidae between the three morphologically similar genera—Zoothamnium, Myoschiston, and Zoothamnopsis.  相似文献   

8.
Puccinia dioicae var. micropuncta and P. caricis-stipatae complete their life cycle by host-alternating between Artemisia (spermogonial-aecial stage) and Carex (uredinial-telial stage). These species are suggested to be biologically distinct by inoculation experiments and field observations. Two additional Puccinia ferruginosa and P. artemisiae-keiskeanae produce only telial stage on Artemisia. Similarities in the teliospore morphology and host relationship of the four Puccinia species suggest their close phylogenetic relationship. Nucleotide sequences of D1/D2 region and ITS2 regions with partial 5.8S rDNA were analyzed to depict possible phylogenetic relationships among the four Puccinia species. In D1/D2 analysis, both macrocyclic and microcyclic species were closely positioned in one clade, not permitting resolution of the phylogenetic relationship between the species. The DNA sequence of ITS2 including partial 5.8S rDNA was sufficiently variable to separate two macrocyclic species and P. artemisiae-keiskeanae; however, confident resolution of phylogenetic relationships of the three species was not possible. Nevertheless, the analysis suggested the derivation of P. artemisiae-keiskeanae from a macrocyclic, heteroecious ancestor that is most likely to be an ancestor of both P. caricis-stipatae and P. dioicae var. micropuncta. In contrast, three isolates of morphologically identifiable P. ferruginosa were variously positioned in the phylogenetic tree, suggesting that P. ferruginosa is not monophyletic.Contribution no. 192, Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan  相似文献   

9.
A pea rust fungus, Uromyces viciae-fabae, has been classified into two varieties, var. viciae-fabae and var. orobi, based on differences in urediniospore wall thickness and putative host specificity in Japan. In principal component analyses, morphological features of urediniospores and teliospores of 94 rust specimens from Vicia, Lathyrus, and Pisum did not show definite host-specific morphological groups. In molecular analyses, 23 Uromyces specimens from Vicia, Lathyrus, and Pisum formed a single genetic clade based on D1/D2 and ITS regions. Four isolates of U. viciae-fabae from V. cracca and V. unijuga could infect and sporulate on P. sativum. These results suggest that U. viciae-fabae populations on different host plants are not biologically differentiated into groups that can be recognized as varieties.Contribution no. 184, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

10.
To clarify the diversity of Astraeus in Japan, 35 collections of Astraeus basidiomata from Japan and Thailand were examined for their morphological characteristics and the nucleotide sequences of the rDNA ITS region and compared with several worldwide Astraeus species. Japanese Astraeus specimens were separated into two groups based on basidiome size, shape of exoperidium, and ornamentation and size of basidiospores. The phylogenetic tree analyses supported the separation, and the morphological groups belonged to different clades. The Japanese Astraeus group 1, morphologically matched to Astraeus hygromerticus var. koreanus, showed the closest phylogenetic relationship with Astraeus hygrometricus from North American and Mediterranean regions, suggesting that the Astraeus group 1 can be indentified as A. hygrometricus var. koreanus. Another Astraeus group, group 2, morphologically matched to A. hygrometricus s.l., showed a distinct monophyletic clade that was separated from A. hygrometricus complexes, indicating an undescribed species.  相似文献   

11.
Noriko Kinjo  Mu Zang 《Mycoscience》2001,42(6):567-574
Cordyceps is one of the target genera for modern mycological studies. Among themCordyceps sinensis is the most famous but poorly defined species because the fungus is endemic in districted regions of east Eurasia. We have explored the various growing regions and habitats where the fungus grows in the wild. We also examined authentic cultures for the species. We analyzed the sequences of ITS1, 2 and 5.8 S rDNA regions ofC. sinensis materials collected from 11 localities of southwestern China. Phylogenetic analyses were performed with these sequences and with additional sequences obtained from GenBank. All sequences formed a single cluster, which comprised two subgroups. Our results strongly suggested that intraspecific variation was rather small and that some species that are morphologically similar toC. sinensis but with different names might be synonymous withC. sinensis. The difference in the pharmaceutical activity among these collectedC. sinensis from different regions will be studied in the future.  相似文献   

12.
An entomopathogenic fungus (IndGH 96), identified as Paecilomyces reniformis, was isolated from long-horned grasshoppers (Orthoptera: Tettigoniidae) in Sulawesi, Indonesia. The phenotypic and molecular data identified the IndGH 96 as a P. reniformis. We present the first comprehensive characterization of this species using morphological features, sequencing of the ITS1-5.8s-ITS2 region, D1/D2 region of 28S of rDNA, and a portion of the tubulin gene, and laboratory bioassays. Distinguishing features include a hyphal body stage during vegetative growth and the production of distinctly curved, light-green conidia. High dosage bioassays showed that IndGH 96 was infectious to both long-horned and short-horned grasshoppers but not to the house cricket, Acheta domestica, or to the lepidopterans velvetbean caterpillar, Anticarsia gemmatalis or fall armyworm, Spodoptera frugiperda. Phenotypic and genetic analyses suggest that IndGH 96 and other isolates of P. reniformis are more closely related to Nomuraea rileyi than to other species of Paecilomyces.  相似文献   

13.
Downy mildew is probably the most widespread and potentially destructive global disease of spinach (Spinacia oleracea). The causal agent of downy mildew disease on various plants of Chenopodiaceae, including spinach, is regarded as a single species, Peronospora farinosa. In the present study, the ITS rDNA sequence and morphological data demonstrated that P. farinosa from S. oleracea is distinct from downy mildew of other chenopodiaceous hosts. Fifty-eight spinach specimens were collected or loaned from 17 countries of Asia, Europe, Oceania, North and South America, which all formed a distinct monophyletic group. No intercontinental genetic variation of the ITS rDNA within Peronospora accessions causing spinach downy mildew disease was found. Phylogenetic trees supported recognition of Peronospora from spinach as a separate species. Microscopic examination also revealed morphological differences between Peronospora specimens from Spinacia and P. farinosa s. lat. specimens from Atriplex, Bassia, Beta, and Chenopodium. Consequently, the name Peronospora effusa should be reinstated for the downy mildew fungus found on spinach. Here, a specimen of the original collections of Peronospora effusa is designated as lectotype.  相似文献   

14.
Phylogenetic analyses of Erysiphe alphitoides s. lat. using sequences of the rDNA ITS region and the D1/D2 domains of the 28S rDNA revealed a complex consisting of several genetically and morphologically distinguished taxa, including the already described Erysiphe alphitoides s. str. and E. hypophylla. The ascomata (chasmothecia) of E. hypophylla are morphologically very similar to those of E. alphitoides, but the two species are easily distinguishable by their symptoms, as well as the shape and size of the conidia. The fungus on Quercus phillyraeoides, distributed in warmer regions in southern Japan, is genetically clearly separated from E. alphitoides s. str., and morphologically characterized by having chasmothecia with appendages consistently shorter than the chasmothecial diameter. This fungus, named Erysiphe quercicola in this paper, is also able to infect some other oak species, and it is genetically identical with anamorphs on some tropical trees of other host genera. Collections of E. alphitoides s. lat. on Quercus acutissima and Q. variabilis, both belonging to Quercus sect. Cerris, are genetically distinct from E. alphitoides s. str., E. hypophylla and E. quercicola. They form two genetically and morphologically differentiated groups. The hypophyllous taxon on Q. acutissima and Q. variabilis, named Erysiphe hypogena in this paper, is characterized by forming distinctive persistent hypophyllous mycelial patches, causing necrotic discolouration of the host tissue. The epiphyllous taxon on these hosts, for which the name E. epigena is proposed, differs in having epiphyllous mycelium, smaller chasmothecia with fewer appendages, and does not cause leaf discolouration.  相似文献   

15.
We investigated the genetic variations of the samples that were tentatively identified as two cultivated Porphyra species (Porphyra yezoensis Ueda and Porphyra tenera Kjellm.) from various natural populations in Japan using molecular analyses of plastid and nuclear DNA. From PCR‐RFLP analyses using nuclear internal transcribed spacer (ITS) rDNA and plastid RUBISCO spacer regions and phylogenetic analyses using plastid rbcL and nuclear ITS‐1 rDNA sequences, our samples from natural populations of P. yezoensis and P. tenera showed remarkably higher genetic variations than found in strains that are currently used for cultivation. In addition, it is inferred that our samples contain four wild Porphyra species, and that three of the four species, containing Porphyra kinositae, are closely related to cultivated Porphyra species. Furthermore, our PCR‐RFLP and molecular phylogenetic analyses using both the nuclear and plastid DNA demonstrated the occurrence of plastid introgression from P. yezoensis to P. tenera and suggested the possibility of plastid introgression from cultivated P. yezoensis to wild P. yezoensis. These results imply the importance of collecting and establishing more strains of cultivated Porphyra species and related wild species from natural populations as genetic resources for further improvement of cultivated Porphyra strains.  相似文献   

16.
The Chinese Bai-Ling-Gu is a mushroom named Pleurotus eryngii var. tuoliensis C.J. Mou. This species has been identified as P. nebrodensis or P. eryngii var. nebrodensis. We examined its taxonomic position by analysis of mating, cultivation, and rDNA sequences, and concluded as follows. (1) Bai-Ling-Gu mated with P. eryngii var. eryngii, and the F1 and F2 formed fruit bodies. (2) Bai-Ling-Gu mated with P. eryngii var. ferulae, and the F1 formed fruit bodies. (3) In the di-mon mating test, P. eryngii var. nebrodensis from Sicily mated with monokaryons of P. eryngii var. eryngii but mated hardly at all with those of Bai-Ling-Gu and P. eryngii var. ferulae. The di-mon mating pattern of Bai-Ling-Gu resembled those of P. eryngii var. ferulae. (4) The partial sequences of rDNA ITS1 and IGS1 from the epitype of P. nebrodensis were identical with those from P. eryngii var. nebrodensis from Sicily but differed from those from Bai-Ling-Gu. (5) The strains of P. eryngii var. eryngii and P. eryngii var. ferulae were in a group, the strains of P. eryngii var. nebrodensis from Sicily were in another group, and the strains of Bai-Ling-Gu were in the other group in both the phylogenetic trees based on the ITS1 and the IGS1 sequences. These results led to the conclusion that Bai-Ling-Gu is a variety of P. eryngii and evolved independently in China. It is satisfactory to identify Bai-Ling-Gu with P. eryngii var. tuoliensis C.J. Mou.  相似文献   

17.
Heterogeneity of the rDNA ITS region in Pythium helicoides and the phylogenetic relationship between P. helicoides and closely related species were investigated. In PCR-RFLP analysis of the rDNA ITS region of six P. helicoides isolates investigated, including the type culture, intraspecific variation was found at the HhaI site. The total length of fragments was longer than before cutting, indicating sequence heterogeneity within isolates. Digestion of the cloned rDNA ITS region derived from seven isolates with HhaI revealed polymorphisms among and within single zoospore isolates, and variability of the region was also present among the clones derived from the same isolate. To test whether the rDNA ITS region of closely related species and other regions in the genome of P. helicoides are also variable, the rDNA ITS region of P. ultimum and the cytochrome oxydase II (cox II) gene encoded in mitochondria were sequenced. P. ultimum had little variation in the rDNA ITS region. The cox II gene sequences of both species revealed only a low intraspecific variability and no intra-isolate variation. In the phylogenic tree based on the rDNA ITS sequences, all clones of P. helicoides formed one large clade that was distinct from the clades comprising morphologically similar species, such as P. oedochilum and P. ostracodes, and was closely related to P. chamaehyphon rather than the other species.  相似文献   

18.
We examined the phytopathological and biological characters ofBotryosphaeria spp. isolated from apples and other deciduous fruit trees, and determined the nucleotide sequences of their rDNA ITS regions. TheBotryosphaeria isolates from deciduous fruit trees can be divided into three groups based on their production of warts on twigs, size of the conidia, and nucleotide sequences of rDNA ITS 1, ITS 2 and 5.8S rDNA. Isolates ofBotryosphaeria in ITS group A produced conidia of intermediate size and showed warts on infected twigs prior to the development of ring rot on fruit. This group was common on deciduous fruit trees in Japan as a causal agent of ring rot and wart bark diseases of apples and pears; and it appears similar to theB. dothidea from the US that was isolated from apple exhibiting white rot. The ITS group BBotryosphaeria produced small conidia and induced shoot blight without wart development prior to the development of ring rot on fruit. This group was localized on pear, persimmon, and kiwi fruit in restricted areas of Japan. The ITS group CBotryosphaeria consisted ofB. obtusa, the causal agent of apple black rot in the US, which produced large dark brown conidia.  相似文献   

19.
In this study, the variability within the ribosomal DNA region spanning the internal transcribed spacers ITS1 and ITS2 and the 5.8S gene (5.8S-ITS rDNA) was used to differentiate species in the genus Pichia. The 5.8S-ITS rDNA region was PCR-amplified and the PCR product digested with the enzymes CfoI, HinfI, and HaeIII. The variability in the size of the amplified product and in the restriction patterns enabled differentiation between species in the genus Pichia, and between Pichia species and yeast species from other genera in the Yeast-id database (). Moreover, the restriction fragment length polymorphism (RFLP) patterns of the 5.8S-ITS enabled misidentified strains to be detected and revealed genetic heterogeneity between strains within the Pichia membranifaciens and Pichia nakazawae species. Ultimately, the RFLP patterns of the 5.8S-ITS rDNA failed to differentiate between some Pichia and Candida species that could be distinguished on the basis of the sequence of the 5.8S-ITS rRNA region or the sequence of the D1/D2 domain of the 26S rDNA gene.  相似文献   

20.
The genus Neoerysiphe belongs to the tribe Golovinomyceteae of the Erysiphaceae together with the genera Arthrocladiella and Golovinomyces. This is a relatively small genus, comprising only six species, and having ca 300 species from six plant families as hosts. To investigate the molecular phylogeny and evolution of the genus, we determined the nucleotide sequences of the rDNA ITS regions and the divergent domains D1 and D2 of the 28S rDNA. The 30 ITS sequences from Neoerysiphe are divided into three monophyletic groups that are represented by their host families. Groups 1 and 3 consist of N. galeopsidis from Lamiaceae and N. galii from Rubiaceae, respectively, and the genetic diversity within each group is extremely low. Group 2 is represented by N. cumminsiana from Asteraceae. This group also includes Oidium baccharidis, O. maquii, and Oidium spp. from Galinsoga (Asteraceae) and Aloysia (Verbenaceae), and is further divided into four subgroups. N. galeopsidis is distributed worldwide, but is especially common in western Eurasia from Central Asia to Europe. N. galii is also common in western Eurasia. In contrast, the specimens of group 2 were all collected in the New World, except for one specimen that was collected in Japan; this may indicate a close relationship of group 2 with the New World. Molecular clock calibration demonstrated that Neoerysiphe split from other genera of the Erysiphaceae ca 35–45 M years ago (Mya), and that the three groups of Neoerysiphe diverged between 10 and 15 Mya, in the Miocene. Aloysia citriodora is a new host for the Erysiphaceae and the fungus on this plant is described as O. aloysiae sp. nov.  相似文献   

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