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1.
Queiroz  F.M.  de F.S. Muniz  M.  Menezes  M. 《Mycopathologia》2001,150(2):61-65
Alternaria brasiliensis sp. nov., was isolated from leaves of common bean, Phaseolus vulgaris L., showing punctiform non concentric leaf spots of brown color. Besides the symptomatological differences, the new Alternaria species presents distinct type of arrangement of conidia chain, body and beak size. The disease was observed in Montanha county, State of Espirito Santo, Brazil, but not yet reported in the literature. The causal agent of the disease is now described by the first time. The epithet used here is referring to the country where the species has been found. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

2.
A new species ofPhaeosphaeria is described from mangroves in South Africa. InPhaeosphaeria capensis ascospores are 29–36×7–8 μm, cylindric-fusiform or somewhat clavate, widest at the middle, narrow at the base and rounded at the apex, (6-)7-septate, light brown or brown, minutely verruculose and surrounded by a spreading, mucilaginous sheath. It is compared withP. luctuosa andP. berlesei from grasses.  相似文献   

3.
A new species ofGloniella from dead intertidal wood attached to trees ofAvicennia marina is described. It differs from previously reportedGloniella species in having relatively large clavate ascospores.  相似文献   

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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   

6.
Three new species of Candida and a new species of Trigonopsis are described based on their recognition from phylogenetic analysis of gene sequences from large subunit ribosomal RNA, ITS1/ITS2 rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II. Candida infanticola sp. nov. (type strain NRRL Y-17858, CBS 7922) was isolated from the ear of an infant in Germany and is closely related to Candida sorbophila. Candida polysorbophila sp. nov. (type strain NRRL Y-27161, CBS 7317) is a member of the Zygoascus clade and was isolated in South Africa as a contaminant from an emulsion of white oil and polysorbate. Candida transvaalensis sp. nov. (type strain NRRL Y-27140, CBS 6663) was obtained from forest litter, the Transvaal, South Africa, and forms an isolated clade with Candida santjacobensis. Trigonopsis californica sp. nov. (type strain NRRL Y-27307, CBS 10351) represents a contaminant from wine in California, and forms a well-supported clade with Trigonopsis cantarellii, Trigonopsis variabilis and Trigonopsis vinaria.  相似文献   

7.
Rapid adventitious shoot regeneration from leaf explants of European birch   总被引:2,自引:0,他引:2  
The goal of this research was to develop a rapid and efficient system for regenerating shoots from leaf explants of European birch, Betula pendula Roth. Single-node stem explants were established in culture, and microshoots were subcultured every 4 weeks through 12 subcultures. Leaves from glasshouse plants or subcultured shoots were excised from stems, cut into approximately 35-mm2 pieces, and placed on Woody Plant Medium (WPM) containing different combinations of naphthaleneacetic acid (NAA) (0, 3, 6 or 9 M) and benzyladenine (BA) (0, 7.5, 15 or 22.5 M) in a 4×4 factorial design. The percentage of leaf pieces forming shoots and the number of shoots regenerated per explant were recorded after 4 weeks. Only media containing BA without NAA stimulated shoot formation on leaf explants. Fifteen micromolar BA induced the most shoots to form on leaf explants compared to 30, 45 or 60 M of this cytokinin. In addition, shoot regeneration was enhanced up to four-fold between the first and eleventh subculture. Over 90% of the leaf explants regenerated shoots with an average of 18 buds formed per explant for the eleventh subculture. Almost twice as many explants formed shoots if their adaxial side was in contact with the medium rather than oriented away from it. The ability to regenerate shoots from leaves varied among plants, regardless of stock plant age. This reliable shoot regeneration system can be used for rapid shoot proliferation and potentially for genetic engineering of European birch.  相似文献   

8.
Leaf explants harvested from shoot proliferating cultures and intact plants of Liquidambar styraciflua Variegata were placed on solidified Woody Plant medium supplemented with 0.1 mgl-1 (0.5 M) naphthaleneacetic acid and 2.5 mgl-1 (11.1 M) benzyladenine to initiate shoot meristems directly. Leaves from intact plants produced over 4 times more adventitious shoots than leaves from in vitro shoots and had a greater tendency to form shoots on the lamina. The relative developmental age of leaf tissue used dramatically influenced the shoot organogenic response observed for leaf explants from intact plants of L. styraciflua Variegata and Moraine.-Leaves that were either 20% or 50% of full size and still actively expanding were superior to other developmental stages for shoot organogenesis. As developmental leaf age increased throughout the period of leaf expansion, the number of shoots forming on the petiole stub remained constant, whereas shoot formation on the lamina increased 8 fold. Shoots derived from Variegata leaves rooted well and grew normally as plants. Differences in rooting ability and plant size could be detected between groups that had been separated according to explant source (in vitro vs. intact plant) and the location of shoot formation (petiole vs. lamina).  相似文献   

9.
Four novel yeast species are described, two from decaying mushrooms, viz. Candida cretensis and Candida vadensis, and two from rotten wood, viz. Blastobotrys robertii and Candida scorzettiae. Accession numbers for the CBS and ARS Culture Collections, and GenBank accession numbers for the D1/D2 domains of the large subunit of ribosomal DNA are: B. robertii CBS 10106T, NRRL Y-27775, DQ839395; C. cretensis CBS 9453T, NRRL Y-27777, AY4998861 and DQ839393; C. scorzettiae CBS 10107T, NRRL Y-27665, DQ839394; C. vadensis CBS 9454T, NRRL Y-27778, AY498863 and DQ839396. The GenBank accession number for the ITS region of C. cretensis is AY498862 and that for C. vadensis is AY498864. C. cretensis was the only species of the four that displayed fermentative activity. All four type strains grew on n-hexadecane. C. scorzettiae is the only one of the new species that assimilates some phenolic compounds, viz. 3-hydroxy derivatives of benzoic, phenylacetic and cinnamic acids, but not the corresponding 4-hydroxy acids. This is indicative of an operative gentisate pathway.  相似文献   

10.
The taxonomic positions of soil isolates known as Streptomyces groups A, B and C were clarified. Comparative 16S rDNA sequence studies indicated that representatives of all three taxa formed distinct phyletic lines within the Streptomyces tree though the group A strains were shown to be related to Streptomyces griseus and associated validly described species. The taxonomic integrity of all three groups was highlighted by DNA:DNA relatedness and ribotype data though the group A strains encompassed a higher degree of genetic variation than the group B and C strains. In light of these and earlier phenotypic data it is proposed that Streptomyces groups A, B and C be given species status as Streptomyces sanglieri sp. nov., Streptomyces aureus sp. nov. and Streptomyces laceyi sp. nov., respectively. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

11.
The competition density effect and changes of mean total tree weight (w) and stand density (ρ) during course of self-thinning were examined in even-aged pure stands ofEucalyptus camaldulensis Dehn. which were planted in the tropical monsoon region. The level of competition was controlled by changing the initial stand density from 625 trees ha−1 to 40,000 trees ha−1. Hozumi's model was used to describe thew-ρ trajectory with aging of each stand and thew-ρ relation between stands of different densities at each time. The higher density produced trees of smaller mean tree sizes. The higher the density, the sooner self-thinning began. The growth curve ofE. camaldulensis followed the logistic growth curve where both maximum size and intrinsic growth rate change with time. Mean intrinsic growth rate was maximized at initiation of growth after lag time and then gradually decreased as time progressed. Hozumi's model was considered to be the best model with wide applicability for describing and comparing the growth characteristics during the course of self-thinning among different species, especially in tropical forest plantations, in which many diverse species were used for reforestation.  相似文献   

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15.
Three novel isolates of haloalkaliphilic archaea, strains IHC-005T, IHC-010, and N-1311T, from soda lakes in Inner Mongolia, China, were characterized to elucidate their taxonomic positions. The three strains were aerobic, Gram-negative chemoorganotrophs growing optimally at 37–45°C, pH 9.0–9.5, and 15–20% NaCl. Cells of strains IHC-005T/IHC-010 were motile rods, while those of strain N-1311T were non-motile pleomorphic flats or cocci. The three strains contained diphytanyl and phytanyl-sesterterpanyl diether derivatives of phosphatidylglycerol and phosphatidylglycerophosphate methyl ester. No glycolipids were detected. On phylogenetic analysis of 16S rRNA gene sequences, they formed an independent cluster in the Natro group of the family Halobacteriaceae. Comparison of their morphological, physiological, and biochemical properties, DNA G+C content and 16S rRNA gene sequences, and DNA-DNA hybridization study support the view that strains IHC-005T/IHC-010 and strain N-1311T represent separate species. Therefore, we propose Natronolimnobius baerhuensis gen. nov., sp. nov. for strains IHC-005T (=CGMCC 1.3597T =JCM 12253T)/IHC-010 (=CGMCC 1.3598=JCM 12254) and Natronolimnobius innermongolicus sp. nov. for N-1311T (=CGMCC 1.2124T =JCM 12255T).  相似文献   

16.
In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).  相似文献   

17.
The leaf blight and mummy fruit disease fungus of Prunus ssiori in northern Japan is newly named M. ssiori, as a fourth member in the M. padi group of section Disjunctoriae of the genus Monilinia (Sclerotiniaceae). It has been misidentified with Monilinia kusanoi, but recent studies show it is different from M. kusanoi as well as other related species on prunaceous hosts in respect to host relation, pathogenicity, morphology, and gene analysis.  相似文献   

18.
Benzyladenine (BAP) uptake and metabolism were characterized during the key stages of shoot organogenesis in leaf explants of Petunia MD1. Using leaf explant transfer experiments, it was shown that exposure to 2.2 M BAP for 6, 8 or 10 days induced shoot formation on 27, 80 and 100% of the explants respectively, with a concomitant increase in the number of shoots per explant. BAP uptake and metabolism were characterized in leaf explants after 1, 3, 6 or 10 days exposure to [3H]BAP or 10 days exposure plus an additional 2 days on basal medium (10+2). BAP and 9--D-ribofuranosyl-BAP ([9R]BAP) were detected at days 1 and 3 only. Therefore, the BAP free base was not detectable during the shoot induction period between days 6 and 10, as defined by leaf transfer experiments. The BAP ribotide pool was largest on day 1 and decreased to day 10+2. It is possible that the BAP ribotide pool provided either the active cytokinin itself or acted as a short-term storage form for the active cytokinin in petunia shoot organogenesis. Other metabolites detected in petunia leaf tissue included 7--D-glucopyranosyl-BAP ([7G]BAP), 9--D-glucopyranosyl-BAP ([9G]BAP) and an unidentified metabolite C.Abbreviations BAP benzyladenine - [7G]BAP 7--D-glucopyranosyl-BAP - [9G]BAP 9--D-glucopyranosyl-BAP - [9R]BAP 9--D-ribofuranosyl-BAP - [9R-5P]BAP 5-monophosphate of [9R]BAP - [9R-5PP]BAP 5-diphosphate of [9R]BAP - [9R-5PPP]BAP 5-triphosphate of [9R]BAP - TEA Triethylamine This research was supported in part by NSF Grant DCB-8917378 to J.D.C. and USDA-CRGO Grant 89-37261-4791 to T.J.C.  相似文献   

19.
The effects of hyperthermia on phagocytosis and killing of Sporothrix schenckii by polymorphonuclear leukocytes (PMNs) were investigated in order to clarify the mechanism of local thermotherapy for sporotrichosis. Yeast cells of S. schenckii, PMNs and serum were incubated at 37°C or 40°C for 2 or 4 hours. Rate of phagocytosis and killing rate (rate of germination) were estimated, and their processes were observed by transmission electron microscopy. There was no effect of hyperthermia on the phagocytosis rate, but the killing rate increased significantly at 40°C. Electron microscopic examination showed an increase of granularity in the yeast cytoplasm, elongation and fragmentation of the cell membrane. The ultrastructural changes were basically identical under both temperatures, but the degree of these changes was higher at 40°C than at 37°C. Although both intact and degenerated yeasts were found in the same conditions, their transient forms were few, suggesting that the PMN-killing process was completed promptly.  相似文献   

20.
A new species of the genus Zygozyma, Z. suomiensis, is described, based on the study of a single strain, derived from a bovine skin lesion.  相似文献   

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