首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Sixty-seven isolates of Bipolaris sorokiniana of barley, belonging to three groups (black, white and mixed) were studied to find an association of melanin with the spore production of the fungus. Conidiogenesis in black, white and mixed subpopulation of B. sorokiniana was positively correlated with melanin content/g of mycelium. Primary hyphae of black and mixed subpopulation differentiated into secondary hyphal structures which subsequently produced conidiophores and conidia. Primary hyphae could not differentiate into secondary hyphae and subsequently conidiophores and conidia in white subpopulation. A melanin containing mutant developed from white subpopulation regained its ability to differentiate into secondary hyphae, conidiophores and conidia. Results showed that melanization of mycelia B. sorokiniana mycelia is an important factor for conidia production.  相似文献   

2.
Diplococcium dimorphosporum sp. nov., D. racemosum sp. nov., D. singulare sp. nov. and D. pulneyense Subram. & Sekar collected from plant debris in natural areas of Spain are described and illustrated. The first species is characterized principally by the production of branched conidiophores and short chains of conidia. Diplococcium singulare has unbranched conidiophores, and conidia produced usually at the tip of conidiophores and from lateral spherical conidiogenous cells. In addition, both species develop a Selenosporella synanamorph with narrow falcate conidia. Diplococcium racemosum produces branched, verrucose conidiophores, and verrucose conidia in long branched chains. Diplococcium pulneyense is the second record, being described for first time on the natural substratum and re-described in pure culture. A key to currently accepted species of Diplococcium is provided.  相似文献   

3.
4.
Two new hyphomycetous anamorphs were isolated from plant hosts of the Restionaceae in the fynbos of the Cape Floral Kingdom of South Africa. Parasarcopodium ceratocaryi gen. et sp. nov. on Ceratocaryum decipiens produces aseptate, cylindrical conidia with amorphous mucoid appendages at both ends in rows or whorls of phialides on verruculose, mononematous conidiophores. Rhexodenticula elegiae sp. nov. on Elegia capensis produces pale brown, fusiform or broadly fusiform, 3-septate conidia on denticles located in the upper part of smooth, geniculate conidiophores. The morphological characteristics of both taxa are described, illustrated, and contrasted to other morphologically similar fungi. To elucidate the phylogenetic relationships of Parasarcopodium, partial large subunit rRNA (28S) gene sequence was generated from the ex-type strain, which revealed it to be a member of the Bionectriaceae (Hypocreales).  相似文献   

5.
Helicoma chiayiense sp. nov. and Helicosporium taiwanense sp. nov. on decaying wood submerged in a freshwater stream of Alishan area, Chiayi County, Taiwan, are described and illustrated with light and scanning electron micrographs. Helicoma chiayiense is distinct in having hyaline conidiophores arising from repent mycelium, producing broad conidia that bear secondary conidia. Helicosporium taiwanense is distinct in having robust poly-denticulate conidiophores producing conidia with a wide conidial filament. The phylogenetic relationship of these species was sought among representative taxa of the helicosporous hyphomycetes by comparing their ITS of the ribosomal DNA (rDNA).  相似文献   

6.
Parablastocatena tetracerae gen. et sp. nov. and Corynesporella licualae sp. nov., collected on dead branches of Tetracera asiatica and Licuala fordiana, respectively, in tropical forests of China, are described and illustrated. Parablastocatena tetracerae is the type species for a new monotypic genus in possessing macronematous conidiophores forming distinct synnemata with holoblastic conidiogenesis and euseptate, short-chained conidia ending in a paler brown rostrum, whereas C. licualae is distinguished from described species by the smaller conidia with long appendages. A key to currently accepted species of Corynesporella is provided.  相似文献   

7.
Spadicoides lushanensis sp. nov., S. multiseptata sp. nov. and S. rostrata sp. nov. are described and illustrated from specimens collected on dead branches of unidentified plants in Lushan Mountain, China. Spadicoides lushanensis is characterized by obclavate, rostrate, pale brown, 40–65?×?4.5–5.5 μm, smooth, 6–8-euseptate conidia. Spadicoides multiseptata is easily distinguished by obclavate, smooth, 11–15-euseptate, 65–115?×?11.5–13 μm, brown to pale brown conidia with a subacute apex. Spadicoides rostrata differs from other described Spadicoides species by obclavate, rostrate, pale brown, 40–65?×?10.5–12.5 μm, smooth, predominantly 5-euseptate conidia. A dichotomous key to Spadicoides species is provided.  相似文献   

8.
9.
10.
Sporidesmioides thailandica gen. et sp. nov., isolated from herbaceous litter in northern Thailand, is described and illustrated. The new genus is characterised by sporidesmium-like, septate, solitary, acrogenous, pale brown to brown, obclavate, conidia, which taper towards the apex and are truncate at the base and septate conidiophores similar to those of Sporidesmium species in Sporidesmiaceae (Sordariomycetes). It differs from similar genera by the presence of a stromatic base, polyblastic conidiogenous cells and a distinct, colourless sheath at the conidial apex. Phylogenetic analyses of combined LSU, SSU, TEF1-α and RPB2 sequence data show that the new taxon, Sporidesmioides thailandica, forms a separate, single clade with Torulaceae in Pleosporales, Dothideomycetes, and is distinct from Sporidesmiaceae (Sordariomycetes).  相似文献   

11.
《Mycoscience》2014,55(4):299-307
Minimelanolocus bicolorata sp. nov., Paradendryphiopsis elegans sp. nov. and Corynesporella bannaense sp. nov., are described and illustrated. Minimelanolocus bicolorata is unique in possessing the schizolytic conidial secession and solitary, acropleurogenous, holoblastic conidia that are ellipsoidal, 3-euseptate, 30–35 × 7.5–9.5 μm, verruculose, pale brown, with an appendage at each end. Paradendryphiopsis elegans is characterized by monoblastic conidiogenous cells producing short chains of conidia that are 13–30.5 × 4–6.5 μm, 2–3-euseptate and fusiform to obclavate. Corynesporella bannaense is distinguished by terminal and integrated or discrete, monotretic conidiogenous cells that arise as lateral branches from the tip of the conidiophore and solitary conidia that are 12–16-distoseptate, smooth, obclavate, thick-walled, pale brown, and 100–140 × 10–14 μm. Keys to species of Minimelanolocus, Paradendryphiopsis and Corynesporella are provided.  相似文献   

12.
In biological particles such as Fusarium species, ice nucleation activity (INA) has been observed. Fusarium strains isolated from apple declined trees in Korea were identified with a multilocus sequence analysis using the tef1 and rpb1 genes. Droplet-freezing and tube-freezing assays were used to determine the INA of the strains, using Pseudomonas syringae pv. syringae KACC 21200 as a positive control and resulting in seven INA+ fungal strains that were identified as F. tricinctum (KNUF-21-F17, KNUF-21-F18, KNUF-21-F29, KNUF-21-F32, KNUF-21-F38, KNUF-21-F43, and KNUF-21-F44). The effect of Fusarium INA+ KNUF-21-F29 was compared to that of INA– strains on Chrysanthemum morifolium cv. Shinma explants. A higher callus formation and no-shoot formation were observed, suggesting that fungal INA could play a role in cold injuries and be a factor to consider in rapid apple decline. To the best of our knowledge, this is the first report of INA fungal strains isolated in Korea.  相似文献   

13.
In the course of taxonomic studies on saprobic microfungi from Spain, several slow-growing, dematiaceous hyphomycetes were isolated from soil, submerged plant material and river sediments. Sixteen of these strains were identified as members of the ascomycete order Chaetothyriales on the basis of morphology and DNA sequence analyses of the internal transcribed spacer region and partial large subunit ribosomal RNA gene. These included three novel species (Cladophialophora pseudocarrionii, Cyphellophora chlamydospora, and Rhinocladiella amoena) and five interesting, little-known or clinically-relevant species (Cyphellophora suttonii, Exophiala aquamarina, E. lacus, E. radicis, and Rhinocladiella similis). In addition, Exophiala oligosperma, an emerging opportunistic fungus, was found for the first time in an aquatic freshwater environment (river sediments). Cladophialophora pseudocarrionii resembles C. carrionii in the branching pattern of its conidial chains, but differs from the latter species in its inability to grow at 30 °C. Cyphellophora chlamydospora differs from other species of the genus in the absence of conidiation, producing only chlamydospores in vitro. Rhinocladiella amoena shows branched conidiophores similar to those of R. anceps, R. atrovirens, R. basitona and R. similis, but differs from them in conidial shape and size. The ex-type strain of Phialophora livistonae, included in the phylogenetic study, clustered with high statistical support with members of the genus Cyphellophora and is transferred to this genus.  相似文献   

14.
15.
A population of simultaneously germinating conidia is an ideal inoculum of the powdery mildew pathogen, Oidium neolycopersici. In conditions of no or low wind velocity, O. neolycopersici successively stacks mature conidia on conidiophores in a chain formation (pseudochain), without releasing the precedent mature conidia. These pseudochain conidia represent a perfect inoculum, in which all conidia used for inoculation germinate simultaneously. However, we found that conidia must be collected before they fall to the leaf surface, because the germination rate was lower among conidia deposited on the leaf surface. We used an electrostatic spore collector to collect the pseudochain conidia, and their high germination rate was not affected by this treatment. The spore collector consisted of an electrified insulator probe, which created an electrostatic field around its pointed tip, and attracted conidia within its electric field. The attractive force created by the probe tip was directly proportional to voltage, and was inversely proportional to the distance between the tip and a target colony on a leaf. Pseudochain conidia were successfully collected by bringing the electrified probe tip close to target colonies on leaves. In this way, conidia were collected from colonies at 3-d intervals. This effectively collected all conidia from conidiophores before they dropped to the leaf surface. A high germination rate was observed among conidia attracted to the probe tip (95.5 ± 0.6 %). Conidia were easily suspended in water with added surfactant, and retained their germination ability. These conidia were infective and produced conidia in pseudochains on conidiophores after inoculation. The electrostatic spore collection method can be used to collect conidia as they form on conidiophores, thus obtaining an inoculum population in which all of the conidia germinate simultaneously.  相似文献   

16.
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   

17.
Gibellulopsis chrysanthemi sp. nov. is described and illustrated from specimens on rotten leaves of garland chrysanthemum (Chrysanthemum coronarium L. var. spatiosum L.H. Bailey), collected in three different sites of Osaka Prefecture, Japan. This species is characterized by having short and long verticillium-like conidiophores, 1-septate, long-cylindrical conidia with tapering ends and slightly brownish chlamydospores. Compared morphologically with other species in the Plectosphaerellaceae (sister to the Glomerellales), G. chrysanthemi is similar to Gibellulopsis nigrescens, from which it differs in the formation of long conidiophores and 1-septate, long-cylindrical conidia with tapering ends. In addition, the molecular analyses of G. chrysanthemi and other members of the Plectosphaerellaceae based on a phylogenetic tree with three-loci (ITS, D1/D2, tef1-α) sequences reveal that G. chrysanthemi is located as a sister group of G. nigrescens.  相似文献   

18.
Collections of Trichoderma producing hyaline ascospores from central China were examined. Four new species, Trichoderma asterineum, T. henanense, T. odoratum and T. pseudobritdaniae, were discovered, described and illustrated. Their phylogenetic positions were explored based on sequence analyses of the combined RNA polymerase II subunit b (rpb2) and translation elongation factor 1 alpha (tef1) genes. As a sister of T. leguminosarum, T. asterineum can be easily recognised by its pale yellow stromata, ochre to brown ostiolar dots surrounded by stellate cracks, green conidia and slow growth. Trichoderma henanense is distinctive in pulvinate or discoid, dirty yellow to brownish yellow stromata, brown to dark brown ostiolar dots, small monomorphic ascospores in relatively short asci and white colonies with dense aerial hyphae in cultures. Trichoderma odoratum forms an independent lineage as a sister of T. henanense and is characterised by yellow to greyish yellow, pulvinate stromata with dark brown or reddish brown projecting ostiolar dots, slow growth, trichoderma- to verticillium-like conidiophores, hyaline conidia and producing a mushroom-like odour in culture. Trichoderma pseudobritdaniae is closely associated with but easily separated from T. britdaniae in pulvinate, brownish yellow or greyish yellow stromata with dark brown or grey black ostiolar dots, relatively large perithecia, monomorphic ascospores, somewhat low growth rate, trichoderma- to verticillium-like conidiophores and hyaline conidia. Morphological distinctions and sequence divergences between the new species and their close relatives are discussed.  相似文献   

19.
Sativumoides punicae gen. et sp. nov. and Cladosporiopsis ovata gen. et sp. nov. are described and illustrated. Sativumoides is characterized by macronematous, individual, percurrently extending conidiophores, integrated, monoblastic, apical, lageniform conidiogenous cells, and single, apical, pale brown to brown, garlic-bulb-shaped dictyosporous conidia with predominantly longitudinal septa. Cladosporiopsis is unique in possessing pigmented, apiosporous conidia seceding schizolytically from integrated, monoblastic, determinate conidiogenous cells; the conidia, arising from the sides or ends of ramoconidia, form short, acropetal chains. Sativumoides is compared with similar anamorphic genera including Triposporium, Iyengarina, Acrodictys, Actinocladium, Piricaudiopsis, Cheiroidea, Stephanoma, Domingoella, Acrogenospora and Shrungabeeja. The distinctions between Cladosporiopsis and similar genera including Cladosporium, Ochrocladosporium, Rachicladosporium, Rhizacladosporium, Toxicocladosporium, Ramularia, Bispora, Lylea and Devriesia are also discussed. Keys to these two novel genera and their morphologically similar genera are provided.  相似文献   

20.
Solicorynespora insolita sp. nov. and Solicory-nespora biseptata sp. nov., collected from plant debris in natural areas of Spain, are described and illustrated. The former species is characterized by obclavate to fusiform, 4- to 7-septate, dark brown conidia, with a mucous tunica at the apex; sometimes with an unusual oblong to bacilliform, hyaline, phialidic conidial synanamorph arising from the apical cell. Analysis of D1/D2 region rDNA sequences revealed that this fungus is related to members of the family Kirschsteiniotheliaceae of the Dothideomycetes. Solicorynespora biseptata is distinguished by obclavate, 2-septate, brown, but pale brown at the apex, smooth conidia. This latter fungus did not grow in culture. A key to species of Solicorynespora is provided.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号