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1.
A powdery mildew fungus on leaves of Dalbergia cultrata var. cultrata (Fabaceae) collected at the Queen Sirikit Botanical Garden in northern Thailand is proven to be a new species of the genus Brasiliomyces and is described as B. chiangmaiensis sp. nov. with light and SEM micrographs. Differences in known Brasiliomyces species are discussed, and a key to species of this genus is provided.  相似文献   

2.
Kretzschmaria varians, a species apparently related to K. micropus, is described as new. It is distinguished primarily by having asci with 2 to 8 ascospores with inconstant germination slit length and remains of synnemata on stromata and surrounding substrate. Xylaria coremiifera, described here as new, bears small fragile coremia on pulvinate stromata and the surrounding substrate. Asci often have fewer than 8 ascospores, most frequently 4. Xylaria umbonata, described here as new, produces perithecia around a central umbo that appears to be the remains of a synnema. Ascospores have long spiralling germination slits.  相似文献   

3.
Isolation of endophytic species of Guignardia (anamorph: Phyllosticta) from healthy leaves of 94 plants (91 species and 3 varieties) in 69 genera, 42 families, was carried out in a test site (Kyoto Herbal Garden) to investigate the host range of Guignardia endophyllicola (anamorph: Phyllosticta capitalensis). Species of Guignardia and Phyllosticta were isolated from the leaves of 67 plants (66 species and 1 variety) belonging to 54 genera, 38 families. Among them, 53 isolates from different plants belonging to 43 genera in 36 families were similar in morphology, and sequence analysis of internal transcribed spacer (ITS) regions of ribosome DNA revealed these isolates to be conspecific with G. endophyllicola. In addition, this fungus was isolated from leaves of various plants collected in different places in Japan and Thailand. Thus, this endophytic fungus has been revealed to live within various vascular plants, angiosperms, gymnosperms, and pteridophytes.  相似文献   

4.
The anamorphic fungus Sporothrix inflata, known as a soil-borne fungus with worldwide distribution, was isolated for the first time from the cortex and central cylinder of living and dead roots of healthy and diseased oak trees (Quercus robur and Q. petraea). Isolation frequencies of S. inflata from oak roots varied according to the health status of trees, oak species, study sites, soil depth and root diameter. Colony morphology and growth rate of isolates are influenced by colony age and type of culture medium.  相似文献   

5.
Interest inin vitro study of entomopathogenic fungi, includingCordyceps species, has been increasing due to their valuable bioactive compounds and biocontrol effects. AmongCordyceps species,in vitro stromata ofC. militaris has been successfully produced and cultivated for industrial purposes. However, genetic study onin vitro stromata formation ofC. militaris has not been carried out yet. Here, relationship between mating system and perithecial stromata formation ofC. militaris is reported. Mating system was determined by observing perithecial stromata formation from mono-ascospore cultures and their pair-wise combinations. Certain combinations of mono-ascospore strains produced perithecial club-shaped stromata, whereas other combinations produced either no stromata or only abnormal non-perithecial stromata. Similarly, monoascospore cultures without combination produced either no stromata or only abnormal nonperithecial stromata. Despite obvious heterothallism, self-fertility was occasionally observed in few strains ofC. militaris. These observations indicated thatC. militaris behaves as a bipolar heterothallic fungus and requires two mating compatible strains in order to produce regular clubshaped perithecial stromata, a fundamental requirement for its industrial cultivation.  相似文献   

6.
During a foray to the mountain rainforests of the Democratic Republic of the Congo, a peculiar species of Xylariaceae was found, which could not be accommodated in any of the existing genera. It is recognised as representative of a new genus, named Ruwenzoria, owing to the presence of a new combination of teleomorphic and anamorphic characters that are regarded as significant for generic segregation within the Xylariaceae. Studies on its secondary metabolites in stromata and cultures by high performance liquid chromatography, coupled with diode array and mass spectrometric detection (HPLC-DAD/MS), and on its phylogenetic affinities based on 5.8S/ITS rDNA sequence data, respectively, revealed a close relationship of the new taxon to the genera Daldinia and Entonaema, from which it differs by having neither a hollow, gelatinous nor a conspicuously zonate stromatal interior, and an anamorph featuring enteroblastic rather than holoblastic conidiogenesis. A specimen from the same geographic region, previously identified as Daldinia bakeri by R.W.G. Dennis was found to constitute a mixture of stromata of Ruwenzoria and an additional, undescribed Daldinia species. The latter fungus is not formally described due to the scantiness of the material, but its morphological characteristics are illustrated.  相似文献   

7.
Hou CL  Piepenbring M 《Mycopathologia》2005,159(2):299-306
Three species of Rhytisma are described based on recently collected specimens from the Anhui province, China. Rhytisma anhuiense is a new species causing a serious tar spot disease on Rhododendron simsii. Rhytisma yuexiense is a new species, which develops its stromata only on fallen leaves of Rhododendron ovatum. Rhytisma himalense on Ilex fargesii is a known species and probably widely distributed in China. Including the two new species, 11 species of Rhytisma are known from China which are presented in a key.  相似文献   

8.
 A new species of Erysiphe sect. Uncinula is described and illustrated from Patagonia, Argentina. Erysiphe patagoniaca sp. nov., found on leaves of Nothofagus × antarctica, is similar to E. nothofagi and E. kenjiana, but differs in its appendages being twisted throughout their length and the number of appendages, asci, and ascospores. The two endemic species of Erysiphe sect. Uncinula, E. magellanica and E. nothofagi, coexisted on the same leaves together with Erysiphe patagoniaca. Received: September 19, 2002 / Accepted: November 28, 2002 Acknowledgments The authors are grateful to Ms. Seiko Niinomi for providing the micrographs of ascomata of Erysiphe spp. on Nothofagus. Correspondence to:S. Takamatsu  相似文献   

9.
A strain LF70 endophytic fungus was isolated from the leaves of Huperzia serrata. The fungus was identified as Cladosporium cladosporioides LF70 according to its morphological characteristics and nuclear ribosomal DNA ITS sequence analysis. The strain could produce Huperzine A (HupA) identified through thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC) with authentic HupA. The amount of HupA produced by this endophytic fungus was quantified to be 56.84 μg/L by HPLC, which was higher than that of other reported endophytic fungi, Acremonium sp., Blastomyces sp., and Botrytis sp. Acetylcholinesterase inhibition activity of HupA produced by strain LF70 was also similar to authentic HupA in vitro. Isolation of such a fungus may provide a promising alternative approach to producing HupA, which is used in treating Alzheimer’s disease and preventing further memory degeneration.  相似文献   

10.
In order to investigate the possible presence of the chytrid fungus Batrachochytrium dendrobatidis (Chytridiomycota: Chytridiales) in frogs (Amphibia: Anura) of Colombia, we made a retrospective examination of formalin-fixed specimens preserved in natural history collections. Using the staining technique of hematoxylin and eosin to identify B. dendrobatidis in histological slices, we found evidence of the fungus in 3 of the 53 frog species examined from a total of 672 specimens collected in 17 departments within Colombia between 1968 and 2006. The infected specimens were found dead or dying in recent years in high elevation sites, suggesting that chytridiomycosis (the disease caused by the fungus) may represent a significant threat to Colombian amphibians. We conclude that a more extensive search for B. dendrobatidis in museum specimens and wild-caught frogs should be undertaken as soon as possible, using both histological and molecular genetic techniques, in order to further characterize the geographic and taxonomic extent of infections of B. dendrobatidis.  相似文献   

11.
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   

12.
A Sebacinales species was recovered from a clone library made from a pooled rhizosphere sample of Nicotiana attenuata plants from 14 native populations. Axenic cultures of the related species, Piriformospora indica and Sebacina vermifera, were used to examine their effects on plant performance. Inoculation of N. attenuata seeds with either fungus species stimulated seed germination and increased growth and stalk elongation. S. vermifera inoculated plants flowered earlier, produced more flowers and matured more seed capsules than did non-inoculated plants. Jasmonate treatment during rosette-stage growth, which slows growth and elicits herbivore resistance traits, erased differences in vegetative, but not reproductive performance resulting from S. vermifera inoculation. Total nitrogen and phosphorous contents did not differ between inoculated and control plants, suggesting that the performance benefits of fungal inoculation did not result from improvements in nutritional status. Since the expression of trypsin proteinase inhibitors (TPI), defensive proteins which confer resistance to attack from Manduca sexta larvae, incur significant growth and fitness costs for the plant, we examined the effect of S. vermifera inoculation on herbivore resistance and TPI activity. After 10 days of feeding on S. vermifera-inoculated plants, larval mass was 46% higher and TPI activity was 48% lower than that on non-inoculated plants. These results suggest that Sebacina spp. may interfere with defense signaling and allow plants to increase growth rates at the expense of herbivore resistance mediated by TPIs.  相似文献   

13.
Xing YM  Chen J  Cui JL  Chen XM  Guo SX 《Current microbiology》2011,62(4):1218-1224
Endophytic fungi are rich in orchids and have great impacts on their host plants. 53 endophytes (30 isolates from Dendrobium devonianum and 23 endophytic fungi from D. thyrsiflorum) were isolated, respectively, from roots and stems of Dendrobium species. All the fungi were identified by way of morphological and/or molecular biological methods. 30 endophytic fungi in D. devonianum were categorized into 11 taxa and 23 fungal endophytes in D. thyrsiflorum were grouped into 11 genera, respectively. Fusarium was the dominant species of the two Dendrobium species in common. Antimicrobial activity of ethanol extract of fermentation broth of these fungi was explored using agar diffusion test. 10 endophytic fungi in D. devonianum and 11 in D. thyrsiflorum exhibited antimicrobial activity against at least one pathogenic bacterium or fungus among 6 pathogenic microbes (Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus). Out of the fungal endophytes isolated from D. devonianum and D. thyrsiflorum, Phoma displayed strong inhibitory activity (inhibition zones in diameter >20 mm) against pathogens. Epicoccum nigrum from D. thyrsiflorum exhibited antibacterial activity even stronger than ampicillin sodium. Fusarium isolated from the two Dendrobium species was effective against the pathogenic bacterial as well as fungal pathogens. The study reinforced the assumption that endophytic fungi isolated from different Dendrobium species could be of potential antibacterial or antifungal resource.  相似文献   

14.
The only two species of Choiromyces collected up to now in Spain, C. venosus and C. magnusii, were studied with both morphological and molecular methods. Phylogenetic inference of nrDNA ITS and LSU sequences showed that they should be considered independent species in the genus Choiromyces. Choiromyces venosus is a hypogeous fungus, infrequent but naturally present in the Iberian Peninsula, that is imported into Spain from central Europe without any indication of its origin or proper taxonomic identification. It is usually sold as highly-prized edible species of the genus Tuber such as T. magnatum. Choiromyces magnusii is a more frequent hypogeous fungus in Spain that is commercialized in spring on a local scale together with different species in the genus Terfezia. Additionally, the Australian species Reddellomyces westraliensis, which was introduced with Eucalyptus camaldulensis plantations, is cited here for the first time in Spain and Europe.  相似文献   

15.
During a survey of plant-inhabiting fungi in a botanical garden in Japan, some noteworthy fungi were collected from leaf spots of some herbal and arboreal plants. Among them, five new species are described, namely: Phyllosticta. ardisiicola on Ardisia crenata, Phy. aspidistricola on Aspidistra elatior, Phy. kerriae on Kerria japonica, Phy. fallopiae on Fallopia japonica, and Pseudocercospora davidiicola on Davidia involucrata. Passalora pyrrosiae, a new combination for Pseudocercospora pyrrosiae on Pyrrosia lingua, is proposed based on its morphological characteristics designating the neotype specimen.  相似文献   

16.
A new anthracnose disease of Atractylodes chinensis was observed in Liaoning province in China. The causal agent was isolated from diseased leaves. Based on morphology and ITS sequence data, it was identified as a Colletotrichum species belonging to the C. destructivum species complex. A multi-locus DNA sequence analysis (ITS, GAPDH, CHS-1, ACT, TUB2) revealed that the fungus represents a new species that is described here as C. atractylodicola sp. nov. Pathogenicity tests confirmed that the isolated species is the causal agent of the observed anthracnose symptoms on A. chinensis leaves.  相似文献   

17.
Field observations and inoculation experiments revealed that Uromyces appendiculatus var. azukicola has an autoecious and macrocyclic life cycle and produces spermogonia, aecia, uredinia, and telia on Vigna angularis var. angularis and V. angularis var. nipponensis. From inoculation experiments, it was suggested that this rust fungus has different host relationships from other varieties. Morphological examinations revealed that the characteristics of urediniospores and teliospores are different among varieties, although aeciospores are morphologically similar to each other.Contribution no. 182, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan  相似文献   

18.
To evaluate the responses of Quercus crispula and Quercus dentata to herbivory, their leaves were subjected to simulated herbivory in early spring and examined for the subsequent changes in leaf traits and attacks by chewing herbivores in mid summer. In Quercus crispula, nitrogen content per area was higher in artificially damaged leaves than in control leaves. This species is assumed to increase the photosynthetic rate per area by increasing nitrogen content per area to compensate leaf area loss. In Quercus dentata, nitrogen content per area did not differ between artificially damaged and control leaves, while nitrogen content per mass was slightly lower in artificially damaged leaves. The difference in their responses can be attributable to the difference in the architecture of their leaves and/or the severeness of herbivory. The development of leaf area from early spring to mid summer was larger in artificially damaged leaves than in control leaves in both species, suggesting the compensatory response to leaf area loss. Leaf dry mass per unit area was also larger in artificially damaged leaves in both species, but the adaptive significance of this change is not clear. In spite of such changes in leaf traits, no difference was detected in the degree of damage by chewing herbivores between artificially damaged and controlled leaves in both species.  相似文献   

19.
The sporocarps of hypogeous and epigeous fungi are important dietary items for forest dwelling rodents in temperate and tropical forests throughout the world. However, results of some pioneering works have demonstrated that fungi cannot be considered as nutritionally high-quality food items for some mycophagous small rodents. According to these studies, when mycophagous rodents feed on fungus, they showed a minimal digestibility, but whether this applies to most rodent species that include fungi in their diets is unknown. In this study, we experimentally evaluated body mass changes and feed preferences in captive deer (Peromyscus maniculatus) and volcano (P. alstoni) mice when fed on epigeous fungus (Russula occidentalis). In experiment 1, the animals were fed with fungus as the only feedstuff in comparison to regular rodent chow and oat. In experiment 2, the animals were fed with fungus in a free-choice arrangement together with equal amounts of rodent chow and oat. Both species lost ∼15% of their body mass within 4 days when fed on fungus alone, but gained 5–10% body mass during the same time period when ingesting oat and rodent chow, respectively, as the only feedstuff. However, in contrast, in the free-choice arrangement with all three feedstuffs, both species gained 20–30% body mass, and showed the highest feed preference for fungus followed by oat and rodent chow. In addition, apparent digestibility of energy and nitrogen were analyzed in both rodent species, which were 50–60% for fungus, whereas approximately 90–94% for rodent chow and oat. According to our results, animals need to supplement their diets with alternative high-quality food items in order to maintain and increase their body mass, suggesting that epigeous fungi are only of moderate nutritional value for small rodents. Futures studies should focus on exploring the importance of a mixture of fungal species in the diet of small mycophagous rodents.  相似文献   

20.
Logistic regression analysis was used to analyse sex allocation in a population of the leaf-cutting ant Acromyrmex balzani occurring in a pasture in southern Brazil. The field sample consisted of 151 fungus-garden chambers (18 queenright and 133 queenless), belonging to 50 nests with three vertically stacked chambers per nest on average. Taking nest chamber as the unit of analysis, seven predictor variables were considered: sampling date, chamber depth, chamber volume, weight of fungus garden, presence of a queen, number of large workers, and number of small to medium workers. The population-level numerical proportion of females was 0.548 and the inferred proportional energetic investment in females 0.672. The former was not significantly different from 0.5 (P=0.168), but the latter was (P=0.0003). The proportional investment in females per fungus garden increased with the number of large workers present (P=0.0002) and decreased with the dry weight of the fungus garden (P=0.012). This implies that resource acquisition through foraging is likely to be a major proximate determinant of sex allocation. The negative correlation between female bias and fungus garden weight might be due to developing adult females requiring more food than males, but this hypothesis could not be confirmed by direct statistical evidence.  相似文献   

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