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1.
Conidia of two morphologically different types, one with a basal appendage only and the other with appendage at both ends, were isolated from the stems of Paeonia suffruticosa. Single conidial isolates of both types of conidia yield identical colonies, which then produced both types of conidia on agar media depending on temperature, thus showing that both types of conidia belong to the same fungus. Seimatosporium botan is described based on its morphological characteristics. The teleomorph of the fungus was first found on sterilized P. suffruticosa stems placed on water agar, when grown at 5°C for 2 months in 12-h photoperiod. Discostroma botan is described for this fungus. The teleomorph is also found on the same host in the field.  相似文献   

2.
A new genus, Versicolorisporium, is established for the coelomycetous fungus collected in Japan on dead culms of the bamboos Pleioblastus chino and Sasamorpha borealis. The type species of the genus, V. triseptatum, is characterized by the production of holoblastic, 3-septate, obovoid, versicolored conidia. Versicolorisporium is similar to Toxosporiella, Neohendersonia, Toxosporiopsis, and Scolicosporium in having versicolored conidia, but differs from these genera by the uniloculate pycnidial conidiomata with a periphysate ostiole, lacking paraphyses, and the conidia without black-banded septa. A BLAST search using LSU nrDNA sequence indicates that the new genus is a member of Pleosporales, Dothideomycetes.  相似文献   

3.
Conidiogenesis of the type species and two additional species of the genus Raffaelea Arx & Hennebert are described. In contrast to previous conclusions based on light microscopy that indicate sympodial production of the conidia, we found that conidium development was by annellidic percurrent proliferation in the type species Raffaelea ambrosiae, as well as in Raffaelea arxii and Raffaelea albimanens. Consequently, this mode of conidium development is similar to the conidiogenesis of anamorphs within the Ophiostomatales, but distinguished by sporodochia formed within the genus Raffaelea. These findings reduce the differences between Raffaelea and other anamorphs with annellidic percurrent proliferation of the conidiogenous cells within the Ophiostomatales to different conidiomata and conidiophores, and they support previous reports of the close phylogenetic relationship between Raffaelea and Ophiostoma.  相似文献   

4.
The taxonomic position of the causal agent of fruit rot of olives was determined from fresh collections of the fungus from central Greece. In culture it formed two types of conidia, namely fusiform, hyaline, aseptate conidia typical of the genus Fusicoccum, and dark-walled, ovoid, ellipsoid or fusiform, 1–2 septate conidia that are not typically observed in Fusicoccum. A phylogenetic analysis based on ITS and EF1- sequences placed the fungus within the same clade as Fusicoccum aesculi, which is the anamorph of Botryosphaeria dothidea, and the type of the genus Fusicoccum.  相似文献   

5.
Three new soil fungi from the Bonin (Ogasawara) Islands, Japan are described:Acremonium macroclavatum, characterized by large clavate guttulate conidia;Cylindrocarpon boninense, characterized by 3–7-septate clavate macroconidia, terminal or intercalary chlamydospores, rarely produced unicellular clavate microconidia; andVerticillium hahajimaense, characterized by conidial heads bearing cylindrical conidia, and catenulate chlamydospores.  相似文献   

6.
The new hyphomycete genusAvesicladiella with two species,A. britannica sp. nov., type species, andA. microsperma sp. nov., is described and illustrated. Both species are leaf litter microfungi. The genus closely resemblesVesicladiella, Circinotrichum, Gyrothrix, Ceratocladium andVermiculariopsiella, several hyphomycete genera with comparable characters such as superficial hyphal networks; production of setae; absence of conidiophores; lageniform or ampulliform conidiogenous cells; and hyaline aseptate conidia produced in clusters around the apices of conidiogenous cells. The new genus differs from these by its hyaline, septate setae, typical ‘phialidic’ conidiogenous cells, and hyaline, aseptate cylindrical conidia.  相似文献   

7.
8.
Two new species of Pyrenomycetes from forest soil in New Caledonia,Anthostomella pacifica andChaetomium novaecaledonicum, are described and illustrated.Anthostomella pacifica is characterized by non-ostiolate ascomata, cylindrical asci with an amyloid apical apparatus, and two-celled ascospores (dark apical cylindrical and hyaline basal dwarfed cells) with longitudinal germ slits.Chaetomium novae-caledonicum is characterized by ostiolate ascomata, straight terminal hairs, arcuate lateral hairs with a recurved tip, and very small, ovoid-flattened ascospores.This research was supported in part by Monbusho International Scientific Research Program: Field Research, No. 05041093.  相似文献   

9.
报道从中国东部暖温带地区诸省(市)土壤中分离到的皮司霉属 Pithomyces 真菌的两个新种:长棒孢皮司霉 Pithomyces longiclavisporus和淡色皮司霉Pithomyces pallidus,及两个中国新记录种:卡罗皮司霉 Pithomyces karoo和帕夫皮司霉Pithomyces pavgii;对另外三个已知种亦作了分离地点和生境的引证。研究过的标本(干制培养物)与活菌种保存在山东农业大学植物病理学标本室(HSAUP)。  相似文献   

10.
Twenty graminaceous plant species were evaluated for their susceptibility to the two sorghum ergot pathogens Claviceps sorghi and Claviceps africana. Five species viz., Sorghum arundinaceum, Sorghum halepense, Sorghum versicolor, Sorghum virgatum and Pennisetum glaucum were found to become infected by both pathogens via inoculation with 106 conidia/ml. Species which did not become infected under these conditions included Pennisetum pedicellatum, Zea mays, and species of Panicum, Brachiaria, Cenchrus, Andropogon, Dichanthium, Chrysopogon, Iseilema, Bothriochloa and Chloris. Honeydew secretions were observed from infected flowers of susceptible plant species. There was marked variation in size of macroconidia of both C. sorghi and C. africana on different hosts on which the pathogens were able to establish symptoms. Dimorphism was observed for macroconidia produced on P. glaucum, as elliptical and spindle shaped macroconidia were observed. Based on inoculation under greenhouse conditions, we conclude that C. sorghi and C. africana may have similar host ranges.  相似文献   

11.
Cohen  Rosa Graciela 《Hydrobiologia》2002,486(1):91-100
At present, the American genus Thamnocephalus has three species, recorded from several states of U.S.A., México and Venezuela: Thamnocephalus platyurus Packard, T. mexicanus Linder and T. venezuelensis Belk & Pereira. The new species Thamnocephalus salinarum, from a turbid saline temporary pond inside the Salinas Grandes of Córdoba, Argentina is described here. The new species differs from all other congeners by the presence in the male, of an unbranched frontal appendage and a pair of soft cordiform parapenial lobes; also, by the sexually dimorphic caudal fin-like lobe. This new species may represent a new genus, however since only five specimens were collected it was not possible to observe if the penial ornamentation conforms to the Thamnocephalus type. Therefore, a conservative position is taken until new material allows proper analysis, by keeping the new species in the genus Thamnocephalus under the new subgenus Simplicephalus.  相似文献   

12.
The genus Ulocladium represents phaeodictyosporic Hyphomycetes that produce conidia that are essentially obovoid in shape. Previous molecular studies that included Ulocladium and related taxa in Alternaria, Embellisia, and Stemphylium revealed a conflict between morphology and phylogeny, and Ulocladium was supported as polyphyletic with a paraphyletic core group. Moreover, the genus consistently resolved within a larger Alternaria/Ulocladium clade, resulting in paraphyly of Alternaria and questions as to the taxonomic status of Ulocladium. In the present study, 13 Ulocladium species and three genetic loci were included for a more comprehensive systematic analysis of the genus than had previously been conducted. Total genomic DNA was extracted from representative taxa and sequences were determined for the nuclear internal transcribed spacer region, including the 5.8S rDNA gene, and the protein-coding genes glyceraldehyde-3-phosphate dehydrogenase and Alt a1. Subsequent phylogenetic analyses based on maximum parsimony and Bayesian methods included related Alternaria, Embellisia, and Stemphylium spp. Results supported previous findings of polyphyletic and paraphyletic relationships of Ulocladium among other taxa. Ten Ulocladium species clustered into a core Ulocladium clade and all taxa possessed the key diagnostic feature of Ulocladium, namely, conidia essentially obovoid in shape. However, A. cheiranthi and E. indefessa also clustered within this group with high bootstrap support but did not posses this diagnostic feature. This paraphyletic clade resolved basal to the core Alternaria clade with high bootstrap support, unlike previous studies in which its position was imbedded within the primary Alternaria clade. Thus, the status of the genus as an independent lineage and a unique taxon is strongly supported. As previously reported, U. alternariae and U. oudemansii, which posses the key conidium characteristics of Ulocladium, clustered as a separate clade sister to the core Ulocladium clade. Further studies are necessary to determine if these taxa represent an independent lineage or share a common ancestor with other Ulocladium species. Obovoid conidia were poorly represented in the isolate of U. lanuginosum that was included in these analyses (the only U. lanuginosum isolate currently available), and the isolate resolved as A. radicina based upon all three loci sequenced. Based upon these data and the origin of the isolate, which was originally deposited as A. malvae, a reassessment of its identity is supported.  相似文献   

13.
Thind , K. S., and G. S. Rawla . (Panjab U., Chandigarh, India.) A new fungus on Cyperus iria. Amer. Jour. Bot. 48(10): 859–862. Illus. 1961—Duosporium cyperi gen. et sp. nov., collected on Cyperus iria Linn., is characterized by the production of 2 types of conidia, macroconidia and microconidia. The macroconidia are straight, cylindrical, triseptate, with their middle cells dark brown, long, thick-walled, and end cells much paler or subhyaline, short, thin-walled, the middle and the end cells being equally wide. The microconidia are nonseptate, spherical, dark brown, prominently verrucose, and produced apically on the conidiophores like the macroconidia; occasionally also formed as secondary conidia on germinating 3-septate macroconidia in culture. The formation of 2 distinct types of conidia in Duosporium and the features of its macroconidia characteristically differentiate it from its close relative Helminthosporium, although Duosporium. cyperi is not unique among fungi in producing 2 types of conidia.  相似文献   

14.
A new species ofFusarium, F. nisikadoi, isolated fromPhyllostachys nigra var.henonis (bamboo) andTriticum aestivum (wheat) in Japan, is described, illustrated and discussed. This species is differentiated from other known species of the genus by the following characteristics: whitish colony color, long zigzag-like chains of 0–3(-5)-septate clavate conidia, intermixed with pyriform conidia, produced mostly from monophialides and rarely from polyphialides in the aerial mycelium, very long and slender sporodochial conidia, and no chlamydospores. The long chains of septate conidia are known only in this species of the genusFusarium. The conidiophores on the aerial mycelium sometimes proliferate sympodially. The species is tentatively placed in the form-sectionLiseola.  相似文献   

15.
Two xylariaceous fungi were isolated from a nest of a termite, Odontotermes formosanus, that was incubated in a laboratory after collecting from Iriomote Is., Okinawa Pref., in Japan. One of the two fungi was identified as Xylaria angulosa on the basis of the morphology of branched stroma produced on medium, tiny asci, and ascospores having a germ slit. Another fungus is an anamorphic fungus that produces synnemata up to 50 mm long from which dendritic conidiophores branch out. Unicellular conidia are holoblastically produced on a sympodially proliferating conidiogenous cell. Such morphological characters resemble those of the genus Geniculosporium. However, its distinctive synnema formation and dendritic conidiophores do not assign the fungus to Geniculosporium or other known genera and warrant establishment of a new genus. The phylogenetic tree based on the ITS regions of rDNA shows that the fungus is nested in the cluster of the genus Nemania (Xylariaceae), whose species have mainly Geniculosporium-like anamorphs. We describe here the present anamorphic fungus as Geniculisynnema termiticola gen. et sp. nov., and discuss its phylogenetic and ecological relationships to xylariaceous fungi, especially termiticolous species.  相似文献   

16.
Recent collections and the type specimen of Marasmiellus juniperinus, the type species of the genus, were examined. Phylogenetic placement, based on ribosomal large subunit (LSU) and internally transcribed spacer (ITS) sequences, is within the lentinuloid clade, nested among Gymnopus taxa. This placement dictates genus name usage and phylogenetic position of other putative species of Marasmiellus. The mating system is tetrapolar.  相似文献   

17.
A new monotypic Beltrania-like genus, Subsessila, with its type species S. turbinata, is described, illustrated and compared with similar genera. The new genus is introduced in the family Beltraniaceae based on phylogenetic analysis and morphological characters. Subsessila can be easily distinguished from other Beltrania-like genera by dark setae arising from radially lobed basal cells, mostly lacking macronematous conidiophores. Conidiogenous cells are ampulliform or doliiform and produce turbinate to clavate conidia with rostrate proximal end and rounded distal end. Evidence for establishment of the new genus is provided based on morphological comparison and DNA sequence data analyses.  相似文献   

18.
Fungal strain FKA-25, isolated from forest soil collected on Yakushima Island, Kagoshima Prefecture, Japan, was assigned to genus Pseudobotrytis based on its morphological characteristics. Conidiophores were erect, slightly swollen at the end of the tip, and gave rise to umbellate conidiogenous cells that were in an expanded denticulate portion at the end and formed ellipsoidal to clavate conidia in sympodial succession. Identification as species P. terrestris was made on the basis of the character of 1-septate conidium. Although no secondary metabolites have been reported from the genus Pseudobotrytis, four secondary metabolite compounds (designated A to D) were isolated from the culture broth of strain FKA-25. Compounds B to D have been reported previously as FK-17-p2a, lunatinin, and 3,4-dihydro-3,4,8-trihydroxy-1(2H)-naphthalenone, respectively. Compound A was designated sespendole and possessed a novel indole-sesquiterpene skeleton.  相似文献   

19.
The nuclear ITS region of 19 species of Alnus was amplified and sequenced. The inferred molecular phylogeny shows that all species of the genus Alnus form a monophyletic group close to Betula and that the fundamental dichotomy within the genus lies between the subgenera Alnaster and Gymnothyrsus, sensu Murai (1964). The subgenus Alnaster appears to be basal in the genus, based on archaism of morphological features, and branching close to the root of the trees due to low ITS divergence from genus Betula. The monophyly of the section Clethropsis is not supported by the present data: Alnus nepalensis is positioned in the subgenus Gymnothyrsus, away from A. nitida and A. maritima. Surprisingly, A. formosana sect. Japonicae is closely tied to A. maritima sect. Clethropsis, with which it shares few morphological traits, and is separate from A. japonica sect. Japonicae with which it shares many traits. An increase in substitution rate is noted in the group comprising A. formosana, A. maritima and A. nitida relative to the rest of the genus, which appears to have had, on the average, a very slow mutation rate. Alnus glutinosa, the designated type for the genus, appears to be representative of the genus both for morphological characters and evolutionary rate. North-East Asia is comforted in its position of origin of the genus since not only does it have the highest number of species and representatives in all deep branching lineages, there are also fewer transcontinental migrations when a North-East Asian ancestor is postulated than when a North American ancestor is postulated.  相似文献   

20.
Timms  Brian V. 《Hydrobiologia》2002,486(1):71-89
The genus Branchinella is diverse in Western Australia, with 18 species, including four new species described here. B. complexidigitata n. sp. is characterized by an intricate frontal appendage, unlike any within the genus. The other three are less remarkable; B. halsei n. sp. is like B. lyrifera, B. kadjikadji n. sp. belongs to the B. affinis group and B. nana n. sp. is similar to B. simplex; similarities are based on frontal appendage and to a lesser extent on the second antennae and penis. Only two species, B. affinis and B. longirostris, are common and widespread; many of the remainder being localized endemics. The high diversity in Western Australia is explained by broad latitudinal range, habitat diversity, and great age and isolation of the landscape.  相似文献   

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